U.S. DEPARTMENT OF COMMERCE
National Technical Information Service
PB-284 716
State-of-the-Art Report
Pesticide Disposal Research
Midwest Research Inst, Kansas City, Mo
Prepared for
Municipal Environmental Research Lab, Cincinnati, Ohio
Sep 78
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Environmental Protection
Agency
Laboratory
Cincinnati OH 45268
August 1978
Research and Development
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
. 1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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PORTIONS OF THIS REPORT ARE NOT LEGIBLE.
HOWEVER, IT IS THE BEST REPRODUCTION
AVAILABLE FROM THE COPY SENT TO NTIS
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1.
4.
7.
9.
REPORT NO.
EPA-600/2-78-183
2.
TITLE AND SUBTITLE
State-of-the-Art Report:
Pesticide Disposal Research
AUTHOR(S)
Ralph R. Wilkinson,
Gary L. Kelso, Fred C. Hopkin
PERFORMING ORGANIZATION NAME AND ADDRESS
Midwest Research Institute
Kansas City, Missouri 64110
12. SPONSORI NG.AG.ENCY NAME AND ADC
Municipal Environmen
Office of Research &
U.S. Environmental P
Cincinnati , Ohio 45
)RESS
tal Research Lab.--Cin.,OH
Development
rotection Agency
268
TUzSzlTro
5. REPORT DATE
September 1978 (Issuing Date)
6. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
s
10. PROGRAM SLEMEr^Q^ ^ QJ
loceiarfiR rfiiRA
11- CONTRACT/GRANT NO.
68-03-2527
13. TYPE OF REPORT AND PERIOD COVERED
Symposium - September 6-7,78
14. SPONSORING AGENCY CODE
EPA/600/14
15. SUPPLEMENTARY NOTES
Donald A. Oberacker/Laura A. Arozarena Project Officers 513/684-7881
16. ABSTRACT
This research program was initiated with the overall objective of reviewing
published and unpublished information on recent and on-going research and
development on pesticide disposal or conversion methods. The methods were
categorized according to four approaches: incineration; physical/chemical
treatment; biological methods; and land disposal.
The information was evaluated in terms of the technical data base, economic
am and environmental impacts, and potential for disposal of finished
formulations by consumers and for large-scale disposal. Several present
and future "problematic" pesticides were identified. Future research needs
were also identified.
17
a.
18
DESCRIPTORS
Pesticides
Incinerators
Waste Disposal
Detoxification
Degradation
Waste Treatment
DISTRIBUTION STATEMENT
release to public
KEY WORDS AND DOCUMENT ANALYSIS
b.lDENTIFIERS/OPEN ENDED TEflMS C. COSATI Field/Group
State-of-the-Art
Pesticide Disposal 13B
Pesticide Disposal Re-
search Needs
19. SECURITY CLASS (This Report) 21. NC iES
uncl acs i f i °d
20. SECURITY CLASS (This page) 22. PRICE f^0\
unclassified /c^j//
EPA Form 2220-1 (Rev. 4-77)
I1. S. GOVERNMENT MINTING OFFICE: 1978-757-140/1341 Region No. SHI
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EPA-600/2-78-183
September 1978
STATE-OF-THE-ART-REPORT
PESTICIDE DISPOSAL RESEARCH
by
Ralph R. Wilkinson, Gary L. Kelso, and Fred C. Hopkins
Midwest Research Institute
Kansas City, Missouri 64110
Contract No. 68-03-2527
Project Officer
Donald A. Oberacker
Solid and Hazardous Waste Research Division
Municipal Environmental Research Laboratory
Cincinnati, Ohio 45268
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
11
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DISCLAIMER
This report has been reviewed by the Municipal Environmental Research Labora-
tory, U.S. Environmental Protection Agency, and approved for publication.
Approval does not signify that the contents necessarily reflect the views and
policies of the U.S. Environmental Protection Agency, nor does mention of
tradenames or commercial products constitute endorsement or recommendation
for use.
iii
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FOREWORD
The Environmental Protection Agency was created because of increasing
public and government concern about the dangers of pollution to the health
and welfare of the American people Noxious air, foul water, and spoiled land
are tragic testimony to the deterioration of our natural environment. The
complexity of that environment and the interplay between its components re-
quire a concentrated and integrated attack on the problem.
Research and development is that necessary first step in problem solu-
tion, and it involves defining the problem, measuring its impact, and search-
ing for solutions. The Municipal Environmental Research Laboratory develops
new and improved technology and systems for the prevention, treatment, and
management of wastewater and solid and hazardous waste pollutant discharges
from municipal and community sources, for the preservation and treatment of
public drinking water supplies, and to minimize the adverse economic, social,
health, and aesthetic effects of pollution. This publication is one of the
products of that research: a most vital communication link between the re-
searcher and the user community.
This study presents a comprehensive review of information on recent re-
search and development on waste or excess pesticide disposal and conversion
methods.
Francis T. Mayo
Director
Municipal Environmental
Research Laboratory
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ABSTRACT
This research program was initiated with the overall objective of review-
ing published and unpublished information on recent and on-going research and
development on pesticide disposal or conversion methods. The methods were
categorized according to four approaches: incineration} physical/chemical
treatment; biological methods; and land disposal.
The information was evaluated in terms of the technical data base, eco-
nomic cost and environmental impacts, and potential for disposal of finished
formulations by consumers and for large-scale disposal. Several present and
future "problematic" pesticides were identified. Future research needs were
also identified.
Incineration is the most highly developed pesticide disposal technique.
In well-designed systems which are maintained and operated properly, organic
pesticides may be > 99.9% destroyed at 1000°C and a 2-sec retention time with
adequate air. Several types of research incinerators liave accomplished this
level of destruction.
Incineration is both capital- and energy-intensive. Potential environmen-
tal impacts are not completely known, although it is generally recognized
these may be lessened through pollution control devices such as scrubber units.
The residual ash may be toxic and must be properly disposed. The data base for
pesticide incineration needs to be expanded to include more representative
classes of pesticides.
Physical/chemical treatment to detoxify pesticides include several tech-
niques which range from simple alkaline hydrolysis to a microwave plasma
destruction technique that requires reduced pressures and sophisticated elec-
tronics. Four techniques appear amenable to large-scale applications: activated
carbon adsorption; resin adsorption; hydrolysis; and wet air oxidation. Other
methods require more extensive testing and development.
Two chemical conversion methods, chlorolysis and hydrodechlorination, are
potentially useful pesticide disposal alternatives.
Physical/chemical treatment offers a range of capital- and energy-
intensiveness. Potential environmental impacts are largely unknown at present.
The data base for pesticide disposal or conversion needs to be expanded.
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Biological methods are incompletely understood, although utilization of
microorganisms, enzymes, and fluidized bed bioreactors are in a rapid state
of development and show promise for future large-scale application* Increasing
use of Commercially available rotating-disc equipment may be expected*
Biological methods may offer relatively low to moderate requirements of
capital investment and energy consumption. The potential environmental impacts
are largely unknown.-More information is needed on the residual toxicity of
final biological effluents and sludges from the disposal of pesticides. Losses
to the environment of pesticides and degradation products via volatilization,
surface waters, and leaching are incompletely characterized*
Land disposal methods, including landfill, infiltration/evaporation
ponds, encapsulation, etc., are widely used but are under-researched. Land
disposal in the past has usually required relatively low investment, but this
may not be true in the future as land values rise. The potential for environ-
mental hazard due to land disposal of pesticides remains largely an unknown
factor.
Future research needs for land disposal include: detoxification mecha-
nisms and ultimate fate of pesticides in the soil, volatility, leaching,
migration, and questions of residual toxicity of the final products. The data
base needs to be expanded to include more representative classes of pesticides.
This report was submitted in fulfillment of Contract No. 68-03-2527 by
Midwest Research Institute under sponsorship of the Environmental Protection
Agency. Research was completed on November 15, 1977.
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CONTENTS
Foreword. o...e. a±
Abstract* e«.e..e.<,e.... ................. iV
Figures . . xi
Tables . xiii
Metric Equivalents* .......................... xv
Acknowledgements* • •**.*. .................... xvii
Summary xix
!• Introduction o.***9****. •••••••••••••* 1
Objectives and Scope* ............*..... 1
Study Approache ..................... 2
Report Organization ................... 2
2> Conclusions* i.e...................... /
Incineration Methods* .................. 4
Biological Disposal Methods 4
Physical-Chemical Disposal and Conversion Methods .... 5
Land Disposal Methods ...••••••••••••••• 5
3* Recommendations. ..................«•••• 6
Incineration Methods* .................. 6
Physical-Chemical Disposal and Conversion Methods .... 6
Biological Disposal Methods ............... 7
Land Disposal Methods .................. 7
4o Incineration Methods ..................... 8
Introduction* ..........•••••.•••«•« 8
Incineration Criteria .................. 9
Types of Incinerators .................. 9
Multiple-Hearth Incinerators ............ 10
Rotary Kiln Incinerators .............. 11
Fluidized Bed Incinerators ............. 15
Liquid Injection Incinerators* ........... IS
Multiple-Chamber Incinerators* ......••••• 23
Research and Development* ••••*••••••••••• 26
Research and Development Programs* ....•••«• 26
Results. * 40
Potential Impacts .................... 45
Potential Environmental Impacts* .......... ^5
Potential Economic Impacts .............
Future Research Needs ....••••.••••••••• -^
References—Section 4.***********«»«»»« 57
vii
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CONTENTS (Continued)
5* Biological Methods .*...e.*.*e 60
Introduction • *••••••. .*e*..a*9 60
Traditional Biological Disposal Methods* ......... 61
Research and Development • ••...•••....»... 62
Laboratory Research ........... ...*.<» 62
Promising Commercial Technologies .......... 70
Potential Impacts.* * . . . . . . . . . . . . . . . . . . 74
Potential Environmental Impacts ........... 74
Potential Economic Impacts* • *••.•.•••.*« 76
Future Research Needs* ................»» 77
References—Section 5. . . . . . *.•••*....*«. 79
6* Physical and Chemical Disposal Methods* .••.*......« 82
Introduction * ....« 82
Research and Development .......... ....... 82
Gas Phase Disposal Methods ................ 83
Microwave Plasma Destruction* ............ 83
Photolysis .<>.. 89
Liquid Phase Disposal Methods* ..•.•*•*•.**•« 92
Activated Carbon and Resin Adsorption Processes * * * 92
Hydrolysis and Other Simple Chemical Treatment
Processes ....... ........<><>..«. 93
Molten Salt Processes ..............«« 105
Ozonation Methods ••*•.•*••••••.•*•• 117
Wet Air Oxidation (Zimmerman Process) •*.*•«•• 124
Liquid-Solid Phase Disposal Process: Chemical Fixation* • 127
Catalytic Liquid Phase Disposal Processes* •••••«•• 130
Catalytic Dechlorination Utilizing Nickel Boride. . « 131
Reductive Degradation Utilizing Metallic Couples* . * 133
Potential Impacts* ••*•*.•*.••••••••••• 135
Potential Environmental Impacts »e«.o«*«ooo 135
Potential Economic Impacts* *••**. •<>«.<>•* 137
Future Research Needs. .............o.o.» 146
Microwave Plasma Technology ••••••oa*«a** 146
Photolysis. ..<> 0 » e • . e » 146
Activated Carbon and Resin Adsorption *••«**•* 147
Hydrolysis 147
Molten Salt Baths 148
Ozone/UV Irradiation 148
Sonocatalysis and Catalytic Ozonation ... 1^°
Wet Air Oxidation 149
Chemical Fixation 149
Catalytic Dechlorination Utilizing Nickel Boride. • • 149
Reductive Degradation Utilizing Metallic Couples* . . 149
Synopsis. «.<><»•*. •...••.»..eeoe o 150
References—Section 6*®«Qe*.«e • .•«eoooo« 151
viii
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CONTENTS (Continued)
7e Land Disposal Methods. . . ........... ........ 157
Introduction. ...o. .................. 157
Methods of Land Disposal .................. 157
-ICQ
Current Management of Pesticide Wastes in Disposal Sites. . •LJO
Research and Development. ..a... ............
Pesticide Leachate »... .............. 161
Soil Incorporation ........... ....... 166
Potential Impacts » 0 ...... ............. 170
Potential Environmental Impacts » ».ae**....
Potential Economic Impacts ..»•........•
Future Research Needs ..................
References— Section 7..............
80 Alternatives to Pesticide Disposal ........... *e..177
Introductions o » . 0 . • .••..*•••«•«••••• I77
Alternative Methods ...... ........ ...... 177
Selected Chemical Conversion Methods. ........... 178
ChlorolysiSs o o « . . <> ..... . ......... 178
Catalytic Hydrodechlorination. ............ 181
Potential Impacts . o . . o . . .............. 185
Potential Environmental Impacts. ... • »••••»• 185
Potential Economic Impacts «..••••• o . • • • • 186
Future Research Needs. ................ 188
References-=>Section 8*. ................. 190
9o Discussion .....oo.. ............ ...... 1^1
Introductione oo. «..».. .............. 191
Overview of Pesticide Disposal and Conversion Methods ... 191
Evaluation of Pesticide Disposal and Conversion
1 Q^
Methods, o .....................
Technical Information Gaps .............
Recently Identified Problem Pesticides. .......... 195
Selected Disposal Procedures. *..... ......... 197
Disposal of Small Quantities of Pesticides ...... 197
Disposal of Large Quantities of Pesticides ...... 200
New Directions for Disposal Research and Development. ...
Small Quantities of Pesticides ...... ...... 2°1
Disposal of Large Quantities of Pesticides ...... 205
References— -Section 9.. ................. 208
ix
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CONTENTS (Continued)
Appendices
A* Recent Contracts for Hazardous Waste Materials Disposal
Research 209
B. Pesticides and Pesticide Containers: --Regulations—for
Acceptance and Recommended Procedures for Disposal and
Storage 215
C. Site Visits Related to Hazardous and Toxic Material
Disposal 222
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FIGURES
Number
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
Typical major industrial rotary kiln incineration facility •
Horizontally fired liquid waste incineration system. ....
Conceptual drawing of a mobile metal pesticide container
Artistic rendering of mobile rotary kiln for disposal of
Iowa State University Horticulture Station Disposal Pits . .
Schematic of tapered fluidized-bed bioreactor system • • • •
Page
12
13
14
16
17
20
21
22
24
25
34
36
65
66
68
71
84
xi
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FIGURES (Continued)
Number page
18 Quartz mesh basket within microwave plasma reactor* • • • • • 85
19 Examples of pesticide pho to lytic- reactions* ...•.-.» .»...•- «...,. 0 8 e -9.1
20 Schematic of molten salt combustion process .........
21 Schematic of the molten salt pilot plant* *.* ....... 108
22 Schematic flow diagram for recycling carbonate melt • • • • • ^
23 Mobile molten salt waste disposal system* .......... H^
24 APS molten salt incinerator •••••*••*.•...•••
25 Schematic for ozonation/UV irradiation apparatus
26 Schematic diagram of potential reaction of ma lathi on and
ozone/UV irradiation* ••••••••••••••••••• ^
27 Schematic flow diagram of wet air oxidation •••••••••
28 Chemfix process schematic ....... ...... ...*• 128
29 Schematic flow diagram for reduction degradation process. . * 134
30 Schematic diagram of the Hoechst AG chlorolysis process ...
31 Schematic flow diagram for hydrodechlorination process. « o o
32 Experimental reaction process for three chlorinated
hazardous materials .•......•••*o«e...«e
xii
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TABLES
Number
1 Organizations that have Conducted Research on Pesticide
Disposal by Incineration* ...........
Temperatures of Complete Combustion of Pesticides Determined
in Laboratory Experiments ................
Operating Parameters of Incineration Research Tests of
Individual Pesticides ..... ...... ...
4 Summary of Herbicide Orange Biodegradation Laboratory
Results ..................... . ..... 63
5 Biodegradation Ability of Phenobac™ at 30°C (86°F) ...... 73
6 Mobay Facility Recovery with Phenobac™. . ...... .... 75
7 Summary of Microwave Oxygen-Plasma Reactions. ........ 87
8 Chemical Degradation Results for Selected Pesticides ..... 94
9 Successful Chemical Degradation of Four Organophosphorus
Insecticides. .. ....... .... .......... 96
10 Half- Lives of Various Pesticides Under Alkaline Conditions. . 97
11 Summary of TRW Alternate Options for Disposal of Pesticide
Wastes. ...... ........... . ........ 98
12 Summary of MRI Disposal Procedures and Eligible Pesticides. .
13 Chemical Methods for Disposal of Selected Pesticides. .... 104
14 Hazardous Chemicals and Wastes Treated by Molten Salt Bath. . HI
15 Summary of Results of Molten Salt Bath Combustion Tests on
Chemicals ......................... 112
xiii
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TABLES (Continued)
Number
16 Typical Results of Molten Salt Bath Combustion Tests on
Pesticides. ................
Page
17 Typical Results of Ozone/UV Irradiation of Pesticides ... 122
18 Wet Air Oxidation Pesticidal Waste Applications ...... 126
19 Electrical and Carrier Gas Costs for Plasma Reactions in
Laboratory Reactor. ................... 139
20 Total Process Costs and Net Profit for Microwave Plasma
Destruction of PMA. 14°
21 Operating Characteristics and Economic Costs Associated
with Herbicide Removal from Wastewater by Carbon
Adsorption 142
22 Economic Cost Comparisons for Treatment of Chlorinated
Pesticides Wastewater by Activated Carbon and Resin
Adsorbent 143
23 Estimated Costs of Wet Air Oxidation of AMIBEN® Waste . . . 145
24 Operating and Financial Data for a Chlorolysis Facility
Processing 25,000 MT/YR of Organochlorine Waste 187
25 Synopsis of Pesticide Disposal and Conversion Research
Methods 192
26 Technical, Environmental, and Economic Comparison of
Disposal or Conversion Procedures for Pesticides. .... 194
27 Recently Identified Problem Pesticides 196
28 Recommended Disposal Procedures for Small Quantities of
Unused Pesticides 199
29 Estimated Pesticide Production in (Quantities Larger than
1,000 Metric Tons per Year • 204
xiv
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METRIC EQUIVALENTS
Btu x 1,055 = Joule (j)
(°F - 32) x 0.555 = Degree Celsius (°C)
ft x 0.3048 = Meter (m)
ft2 x 0.0929 = Square meter (m2)
gal. x 0.00379 = Cubic meter (m3)
Ib x 0.454 = Kilogram (kg)
ton (short) x 0.907 = Metric ton (MT)
xv
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ACKNOWLEDGEMENTS
This report presents the results of a project performed by Midwest Re-
search Institute under Contract No. 68-03-2527, MRI Project No. 4365-L.
Mr. Donald A. Oberacker has been the project officer for the Environmental
Protection Agency.
The project was conducted from February 15 to November 15, 1977, by
Dr. Ralph R. Wilkinson, Associate Chemist, who served as project leader,
Mr. Gary L. Kelso, Associate Chemical Engineer, and Mr. Fred C. Hopkins,
Junior Environmental Scientist, under the supervision of Dr. Edward Wo
Lawless, Head, Technology Assessment Section. Dr. Alfred F. Meiners, Prin-
cipal Chemist, and Mr. Thomas L. Ferguson, Principal Chemical Engineer, pro-
vided technical and editorial consultation.
Midwest Research Institute expresses its sincere appreciation to the
many individuals, companies, institutions, and agencies who provided tech-
nical information for this report. In particular, we wish to thank the fol-
lowing individuals and companies for the privilege of on-site visits to meet
with technical personnel:
* Mr. Robert Babbitt, Manager Processing Engineering, The Marquardt
Company, Van Nuys, California
* Dr. Lionel Bailin, Research Chemist, Lockheed Palo Alto Research
Laboratory, Palo Alto, California
* Dr. Charles Hall, Project Leader, Iowa State University, Horticul-
tural Research Station, Ames, Iowa
* Mr. Charles Hancher, Group Leader, Bioprocess Engineering, Oak
Ridge National Laboratory, Oak Ridge, Tennessee
* Mr. Sidney Howard, Marketing Manager, Envirotech Corporation, EIMCO
BSP Division, Belmont, California
* Mr. Dale Moody, Program Manager, Combustion Power Company, Menlo Park,
California
xvi
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* Dr. Tan Phung, Research Engineer, 80S Engineers, Inc., Long Beach,
California
* Mr* Ray Tenzer, Marketing Manager, Energy Systems, MB Associates,
Inc., San Ramon, California
* Dr. Sam Yosim, Research Chemist, Atomics International Division,
Rockwell International, Canoga Park, California
xvii
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SUMMARY
The primary objectives of this project were to collect and review infor-
mation on recent research and development on waste or excess pesticide dis-
posal and conversion methods, with emphasis on high temperature incineration,
biological methods, physical-chemical treatment, and land disposal. Potential
environmental and economic cost impacts, problems of field disposal of fin-
ished pesticide formulations, and present and potential future "problem"
pesticides were also examined. The identification of those disposal methods
that are most nearly ready for practical application was a major goal. Based
on this information, a series of future research needs and new directions
for pesticide disposal R&D were developed.
Information was gathered through an in-depth review of the published
literature, personal contacts by telephone and letter with knowledgeable
sources, and nine site visits to facilities actively engaged in research on
hazardous waste disposal. The results of this study are summarized in the
following paragraphs.
INCINERATION METHODS
High temperature incineration is the most highly developed disposal
method for pesticides as well as many other hazardous waste materials. It
dependably yields predictable results if specified operating conditions are
maintained. Although several classes of pesticides have not been studied,
incineration may provide a complete solution to disposing of a wide range
of pure pesticide active ingredients (Al) as well as finished formulations
and mixtures of pesticides and formulations.
The economics of incineration may be unfavorable since it is a capital-
and energy-intensive method. It is practical and economical only for large-
scale use, i.e., "tonnage," pesticide disposal operations. It is not well
suited to the small-batch operations characteristic of most consumer and
field disposal problems.
A potential for environmental insult exists during incineration of waste
if noxious gaseous effluents are not monitored and controlled through use of
scrubber units, baghouses, etc.; and any scrubber water must be disposed of
properly. Incineration of organometallic pesticides is not recommended since
xviii
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volatile toxic metals, metal chlorides, oxides, etc., may be formed, and
particulates may be difficult to remove from the gaseous emissions.
The major conclusions and recommendations on pesticide incineration are:
* The data base for pesticide incineration has been developed largely
with experimental incinerators. This fact limits extrapolation of the
findings to full-scale conditions. More pilot-scale demonstrations
should be conducted utilizing commercial units so that the results
may be directly applicable to solving field disposal problems.
* Incinerator operating conditions for a 2-sec retention time at or
near lOOOPc with adequate excess air appear to be sufficient for
& 99.9% destruction of the organic pesticides that have been studied
to date.
* The data base for pesticide incineration should be expanded to in-
clude more representative classes of pesticides, particularly anilides,
ureas, uracils, nitrated hydrocarbons, botanicals, and microbiologi-
cal pesticides.
* Potential environmental and economic cost impacts have not been com-
pletely defined as of this time (May 1978).
BIOLOGICAL METHODS
Biological methods utilizing microorganisms or enzymes are in a rapid
state of development at the research level and show promise for future appli-
cation, although many classes of pesticides have not been studied yet. Greater
use of commercially available rotating-disc apparatus (an improvement over
conventional activated sludges processes) may be expected in the future. In-
novations in biological methods may include the use of fluidized bed bioreac-
tors and mutant bacterial strains having above normal tolerance for toxic chem-
icals and other adverse conditions.
The major conclusions and recommendations on biological methods are:
* Sufficient data have not been developed on the extent of applicability
of biological methods for pesticide disposal.
* Biological treatment studies should be expanded to the pilot plant and
demonstration levels, to better establish the utility of these methods
in pesticide disposal.
* More information is needed on the residual toxicity of final biologi-
cal effluents and sludges from the disposal of various classes of pes-
ticides.
xix
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* Studies to determine the amounts of pesticides or pesticide degrada~
tion products that are lost to the environment via volatilization,
surface water, and groundwater contamination during biological treat-
ment should be carried out.
* Potential environmental and economic cost impacts have not been ade-
quately determined and should be studied.
PHYSICAL-CHEMICAL DISPOSAL AND CONVERSION METHODS
Several physical-chemical disposal and conversion methods are perceived
to have potential for large-scale application including: adsorption on acti-
vated carbon and resin; chlorolysis; microwave plasma destruction; molten
salt baths; hydrolysis; reductive degradation with metallic couples; and wet
air oxidation. All of these methods have been demonstrated at the research
level.
The major conclusions and recommendations on physical-chemical disposal
and conversion methods for pesticide disposal are:
* The development of many methods has progressed only as far as the
bench or pilot plant levels, and several representative classes of
pesticides must still be examined by the various physical-chemical
treatment methods.
* At least four methods (i.e», activated carbon absorption, resin
adsorption, hydrolysis, and wet air oxidation) are at or near the
point of practical demonstration and should be given full tests.
* Three other methods (microwave plasma destruction, molten salt baths,
and ozone/UV irradiation) should be further investigated and developed
to reach the demonstration level•
* Two chemical conversion methods (chlorolysis and hydrodechlorination)
> are potentially useful and warrant further study.
* Potential environmental and economic cost impacts have not been ade-
quately determined and should be studied.
LAND DISPOSAL METHODS
Land disposal methods, including landfill operations, infiltration/
evaporation ponds, encapsulation, etc., are often employeds but under-
researched, techniques.
xx
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The major conclusions and recommendations on land disposal methods are:
* The detoxification mechanisms of pesticides and their ultimate fate
are incompletely understood*
* Data deficiencies preclude evaluation of the efficacy and environmen-
tal consequences of land disposal procedures*
* More, information is needed on pesticide volatility, leaching, migra-
tion, the nature of the degradation products, and potential residual
toxicity.
* Studies to monitor losses of pesticides and degradation products from
active disposal sites, including examination of air, surface and
groundwater, should be expanded.
* The capacity of various types of soils to absorb, retain, and degrade
pesticides has not been adequately described and quantified*
* The potential environmental and economic cost impacts have not been
adequately determined and must be studied*
PROBLEMATIC PESTICIDES
The report identifies 55 problematic pesticides which may be considered
as potential or future waste problems because of human health or ecological
concern or specific, widely reported incidents. Of these 55 problematic pes-
ticides, 23 have been researched for potential disposal methods which can be
made environmentally acceptable*
DEMONSTRATED FIELD DISPOSAL METHODS
The report focuses both upon disposal methods for small quantities of
pesticides (< 25 kg or < 20 liters), suitable for use by the layperson, and
upon disposal methods more appropriate to the field disposal or conversion
of "tonnage" quantities of unwanted pesticides. Those disposal methods poten-
tially applicable to the layperson are noted, and demonstrations of their ap-
plication to various pesticide classes are described. For the disposal of
"tonnage" quantities of unwanted pesticide, incineration is cited as a practi-
cal, demonstrated procedure. Other biological and physical-chemical treatments
are not yet sufficiently developed for large-scale utilization. Landfill re-
mains a limited method to date, although this procedure is practiced in Class
1 disposal sites in various parts of the country, e.g., California. In gen-
eral, field disposal research and development has focused largely on the per-
sistent chlorinated hydrocarbons, and much work remains to be done to develop
data for other classes of pesticides.
xxi
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NEW DIRECTIONS FOR DISPOSAL RESEARCH AND DEVELOPMENT
Based on information contained within the body of the report, new direc-
tions for pesticide field disposal research and development are suggested.
For disposal of small quantities of pesticides (< 2 kg or < 20 liters) a
limited number of alkaline hydrolytic degradation studies are proposed. For
disposal of large or "tonnage" quantities of pesticides new research and de-
velopment may focus on incineration at sea, mobile disposal units, and fixed
disposal units including commercial incinerators.
xxii
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SECTION 1
INTRODUCTION
The problems associated with unwanted pesticides and used pesticide con-
tainers have resulted in the initiation of numerous recent or ongoing research
projects* These projects are conducted by various research organizations under
the sponsorship of government agencies, industrial organizations, and private
institutions*
OBJECTIVES AND SCOPE
This program was initiated in order to develop a comprehensive state-of-
the-art review of pesticide disposal research. Primary objectives in the de-
velopment of this document were to:
* Conduct a detailed review of thermal behavior of pesticides and reduce
available information into a concise and usable format.
* Conduct a detailed review and evaluation of bioconversion processes
for pesticides.
* Describe alternatives to disposal via reprocessing, chemical treat-
ment, and other means.
Secondary objectives were to:
* Identify the present and potential future problem areas, with empha-
sis on the consumer sector*
* Identify research and development needs for pesticide disposal.
* Characterize the environmental impacts for various disposal methods,
with emphasis on incineration.
Methodologies used in the development of this review included a computer-
ized search of current research in progress; contact with pesticide disposal
research workers and company representatives; contact with various govern-
mental groups and agencies; and an examination of recent technical litera-
ture on pesticide disposal including governmental documents. Also included
-------
were nine on-site visits to California, Iowa, and Tennessee to obtain first-
hand information on the state of the art of pesticide disposal research*
STUDY APPROACH
The report emphasizes pesticide disposal research and includes sections
on incineration, biological techniques, physical/chemical procedures, and land
disposal* Chemical conversion and recovery procedures are considered in a
separate section.
The approach used to categorize research on field disposal methods for
cancelled, restricted, contaminated, or otherwise unwanted pesticides was to
consider each chemical class, e.g., organophosphorus compounds, chlorinated
hydrocarbons, organometallies, etc*, as being potentially amenable to one or
more of the above conversion, detoxification, or disposal procedures* This ap-
proach permits the information developed in this report to be summarized in
matrix form, which presents conversion and disposal research methods for each
chemical class of pesticides. The matrix identifies technology gaps and dupli-
cate studies.
. The diverse nature of the pesticide industry and its marketing strategy
makes difficult the task of assessing field disposal techniques for specific
active ingredients (Al's) and their finished formulations. For example, there
were some 24,000 different formulations available from 139 manufacturers and
5,660 femulators as of February 1976* Over 50,000 different products are said
to have been registered by the Environmental Protection Agency (EPA). Each
company that markets a given formulation of finished pesticide must have a
registered label for it. Over 3,500 companies hold federal registrations for
one or more products* In addition, many pesticides are registered for inter-
state sale only; an estimated 2,000 pesticidal products are registered in
California alone.
REPORT ORGANIZATION
The information gathered during this study is organized into a format
which will assist governmental agencies in the assessment of various pesti-
cide disposal options which may be viable in the near future or are approach-
ing the demonstration phase.
This report is organized into nine sections and three appendices. The
Summary, Conclusion, and Recommendations sections are placed at the front of
the report to allow the reader an immediate overview. Ongoing research activi-
ties are discussed in the sections on incineration, biological, physical-
chemical, land disposal, and alternative disposal technologies. Section 9,
the last section of the report, presents a discussion of various disposal
-------
research options, information gaps, and potential disposal problems* Also in-
cluded are discussions of disposal methods and safety precautions for the lay-
person disposing of small quantities. The section closes with a discussion of
new research and development directions available to the EPA*
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SECTION 2
CONCLUSIONS
This section presents conclusions regarding pesticide disposal or conver-
sion by incineration, biological methods, physical-chemical treatment, and
land disposal*
INCINERATION METHODS
1. The data base for pesticide incineration has been developed predomi-
nantly from experimental research-type incinerators. This fact limits extrapo-
lation of the findings to full-scale conditions.
2. Incinerator operating conditions and characteristics are dependent
on the nature of the destruction unit and the specific pesticide being de=
stroyed. In general, a 2-sec retention time at or near 1000°C with adequate
excess air appears to be sufficient for 5 99*99% destruction of the organic
pesticides studied to date. However, the chemical and toxicological nature of
the effluents (gas, particulates, solid residue) and the scrubber water have
not been adequately characterized.
3. Potential environmental and economic cost impacts have not been ade-
quately addressed in the literature.
BIOLOGICAL DISPOSAL METHODS
1. Sufficient data have not been developed on the use of biological
*methods for pesticide disposal. Only 14 pesticides have been evaluated for
potential biological disposal, and these were not representative of the major
classes of pesticides.
2. Significant information gaps exist in the present data base, includ-
ing information regarding volatile losses of pesticides and residual toxicity
of final biological effluents and sludges.
3. More research and development are needed at the pilot plant level.
In particular, demonstrations of the use of mutant bacterial strains and
fluidized bed bioreactors to detoxify a number of hazardous chemicals, in-
cluding pesticides in process wastewater, are needed.
-------
4 a Potential environmental and economic cost impacts have not been ade-
quately addressed.
PHYSICAL-GHEMICAL DISPOSAL AND CONVERSION METHODS
1. Sufficient data are not available on pesticides which are represen-
tative of the various classes for which many of these methods are potentially
applicable*
2 a The development of many of the disposal methods discussed in the re-
port has progressed only as far as the bench or pilot plant level* However,
at least four methods (activated carbon, resin adsorption, hydrolysis, and
wet air oxidation) are at or near the point of practical demonstration*
3o Two chemical conversion methods, chlorolysis and hydrodechlorination,
are potentially useful pesticide disposal alternatives.
4. Potential environmental and economic cost impacts have not been ade-
quately addressed.
LAND DISPOSAL METHODS
la Land disposal procedures for hazardous chemicals, including pesti-
cides, have been widely practiced because of economic advantages over, alter-
nate methods. However, the detoxification mechanisms of pesticides, as well
as the ultimate fate in land disposal processes, are incompletely understood
at present. Thus, complete assessment of the environmental consequences of
land disposal is not possible at this time.
2 a Data deficiencies preclude evaluation of the efficacy and environ-
mental consequences of biological disposal methods. Specifically, more infor-
mation is needed regarding pesticide volatility, leaching, migration, the
nature of the degradation products, and potential residual toxicity. The ca-
pacity of various types of soils to adsorb, retain, and degrade pesticides
has not been adequately described and quantified.
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SECTION 3
RECOMMENDATIONS
The following recommendations are presented on methods for the disposal
or conversion of unwanted pesticides and are listed in order of decreasing
potential for full-scale application to the detoxification of pesticides*
INCINERATION METHODS
!• The data base for pesticide incineration should be expanded to in-
clude more representative classes of pesticides (particularly anilides, ureas,
uracils, nitrated hydrocarbons, botanicals, and microbiological pesticides).
More full-scale demonstrations of pesticide incineration should be conducted
utilizing commercial facilities so that the results may be directly appli-
cable to solving field disposal problems.
2. Pollution control devices for specific pollutants should be tested.
One of the pieces of information needed to assist in selection of these de-
vices is information on particle size distribution for solids emitted*
3. The specific combustion products emitted by pesticide incineration
and their potential effects on the environment should be characterized.
4. Capital and operating costs of pesticide incineration (including land
values, waste handling systems, and pollution control equipment) should be de-
termined.
PHYSICAL-CHEMICAL DISPOSAL AND CONVERSION METHODS
1. Physical-chemical disposal and conversion methods (particularly
microwave plasma detoxification, chlorolysis, molten salt baths, and wet air
oxidation) should be further developed to pilot plant or demonstration levels.
2. Research and development activities on other physical-chemical methods
(particularly activated carbon and resin adsorption, hydrolysis, and wet air
oxidation) should continue.
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3» Potential environmental and economic cost impacts for physical-
chemical disposal and conversion methods should be determined.
BIOLOGICAL DISPOSAL METHODS
lo Studies to monitor both pesticide losses and pesticide degradation
product losses via volatilization and surface or groundwater contamination
from traditional biological treatment processes (e.g., activated sludge,
trickling filter, etc.) should be expanded.
2. Biological treatment should be developed to the pilot plant and
demonstration levels to better establish the utility of biological methods in
pesticide disposal, including:
* Conventional waste treatment methods.
* Immobilized enzymes, mutant bacterial strains, and fluidized bed
bioreactors.
* Disposal pits.
3. Potential environmental and economic cost impacts for biological dis-
posal methods for pesticides should be determined.
LAND DISPOSAL METHODS
1. Studies to monitor losses of pesticides and degradation products from
active disposal sites (including examination of air, surface and groundwaters)
should be expanded.
2o Studies to determine the extent of degradation and degradation rates
of land-disposed pesticides should be expanded.
3. Potential environmental and economic cost impacts for land disposal
of pesticides should be determined.
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SECTION 4
INCDERATION METHODS
INTRODUCTION
Among the various alternatives available for the disposal of pesticides,
incineration has been held to be one of the more promising methods. The ad-
vantages of incineration as a pesticide-disposal procedure are that incinera-
tion technology is relatively well developed; systems are stable and depend-
able; large volumes of pesticides can be handled properly; incinerators are
versatile; pollution emissions for incinerators are controllable; there is a
potential for energy recovery from incinerator operations; and volume reduc-
tion of pesticide wastes is 'achieved. Offsetting some of the advantages of
incinerators are that incinerators are expensive; they create an ash which
requires disposal; and they can emit toxic gases, vapors, and particulates,
if not properly controlled.
The EPA (1974) has defined a pesticide incinerator as an installation
capable of controlled combustion of pesticides at either a temperature of
1000°C (1832°F) and a 2-sec retention or dwell time in the combustion zone,
or some lower temperature and sufficient dwell time to assure complete con-
version of the specific pesticide to inorganic gases and a solid ash residue.
While it is generally true that most pesticides can be destroyed by inciner-
ation at a temperature of 1000°C (1832°F) and a residence time of 2 sec, it
is difficult to estimate what the proper operating conditions should be for
a specific pesticide in a given incinerator. There are about 550 different
pesticide Al's and about 24,000 different formulations on the market (Kelso
et al., 1976), and the decomposition temperatures of these compounds and
their related decomposition products vary widely. Research and development
studies by a number of> organizations have been performed on the incineration
of selected pesticides. As a result of this research the efficiencies of
various types of incinerators for destroying specific pesticides have been
determined under a range of operating conditions.
This section of the report presents a discussion of the results of these
research and development programs» Included are summaries of the criteria for
incineration operations; the types of incinerators available; research and
development programs conducted on pesticide disposal by incineration and the
-------
results of those programs; a discussion of environmental and economic impacts;
and a discussion of future research needs.
INCINERATION CRITERIA
Proper incinerator operating conditions are required to achieve a high
degree of destruction of pesticides and related compounds. An incinerator must
be properly designed to provide adequate residence time in the combustion
. chamber, adequate mixing (turbulence) of the waste and combustion air, an ade-
quate temperature to ensure complete destruction of organic compounds, and
adequate oxygen in the combustion chamber for complete combustion. These four
criteria—residence time, turbulence, temperature, and combustion air—must
be considered together to ensure efficient and complete destruction of a pes-
ticide by incineration.
In addition to using the proper operating conditions to destroy the pes-
ticide, the incineration system must be equipped with the proper emission
controls to ensure that toxic gases and particulates do not escape into the
environment. The ash (which may contain hazardous substances) must be properly
disposed. Wet collection equipment is available for the removal of gaseous
pollutants and includes scrubbers of several types: venturi, plate, packed
tower, fiber bed, spray tower, centrifugal, moving bed, wet cyclone, self-
induced spray, and jet. Dry collection equipment is available for the removal
of particulate pollutants and includes settling chambers, baffle chambers,
skimming chambers, dry cyclones, impingement collectors, electrostatic pre-
cipitators, and fabric filters. The incinerator ash, scrubber water, and
particulate collection can then be landfilled, chemically treated, or other-
wise processed for disposal.
Thus, when considering the efficiency and effectiveness of an incinera-
tion operation to dispose of pesticides, the important criteria are: tempera-
ture, residence time, turbulence, and combustion air in the incinerator; com-
bustibility of the pesticide and the feed rate; pollution control equipment
to treat the exhaust gases; and disposal of the incinerator ash and the sub-
stances collected in the pollution abatement equipment. Research conducted on
pesticide disposal by incineration must consider these criteria.
TYPES OF INCINERATORS
Ottinger et al (1973) and Scurlock et al. (1975) have presented a de-
tailed discussion of the types of incinerators available for hazardous waste
disposal. The technical information given in this section is primarily taken
from these two reports unless the text is referenced otherwise.
Incinerator units may be classified into 10 basic types: open pit in-
cinerators, open burning, stack flares, gas combustors, catalytic combustors,
-------
multiple hearth incinerators, rotary kiln incinerators, fluid!zed bed incin-
erators, liquid injection incinerators, and multiple chamber incinerators.
However, only the latter five types are suitable for the disposal of pesti-
cides* Open pit incinerators, open burning, and stack flares are not amenable
to secondary pollution control operations and allow the uncontrolled entry of
the products of combustion into the environment. Gas combustors and catalytic
combustors are applicable to gaseous wastes only, and pesticides are commonly
marketed in either the liquid or solid state. Molten salt bath systems are
covered in.Section 6 (Physical and Chemical Methods). These systems are not
incinerators or furnaces in the normal sense, e.g., at least one type does
not operate with a flame.
Multiple hearth, rotary kiln, fluidized bed, liquid injection, and mul-
tiple chamber incinerators represent proven technology in waste disposal
techniques. The application of the first three types to pesticide disposal
should be useful since they are all versatile units capable of incinerating
a wide variety of solid, liquid, and gaseous combustible wastes. In addition,
each unit can be equipped with appropriate emission control systems and has
the necessary operating conditions to combust pesticides. Multiple hearths,
which reach temperatures of about 1000°C (1830°F), retain solids for up to
several hours. Rotary kilns reach temperatures of 1650°C (300CPF) and may re-
tain solid waste for several seconds to several hours. Fluidized beds reach
operating temperatures of 870° C (1600°F) and have variable retention times.
The liquid injection incinerator is limited to liquids, and this type of unit
reaches temperatures of 1650°C (3000°F) with residence times of up to 1 sec
for gases. The conventional multiple chamber incinerator is typically utilized
for solid wastes and normally operates at a temperature of about 540°C
(1000°F), too low for most pesticides.
Each of the five types of incinerators that may be used to dispose of
pesticides is described briefly below.
Multiple-Hearth Incinerators
This type of incinerator (commonly called a Herreshoff furnace) was orig-
inally developed to incinerate sewage plant sludges. The versatility of
multiple-hearth incinerators has allowed operators to process not only sludges
but other combustible tars, liquids, gases, and solids. Today a wide variety
of industrial and municipal wastes are disposed of by incineration in multiple-
hearth incinerators.
The multiple-hearth furnace consists of a refractory-lined circular steel
shell with refractory hearths stacked vertically. Solid wastes are fed through
the furnace roof and are moved across the top hearth with horizontal plows.
The wastes fall through the top hearth drop holes and then through holes in
each successive hearth until they reach the furnace floor as ash. Residence
10
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time may be up to several hours for some solids. Liquid and gaseous wastes are
injected into the furnace through auxiliary burner nozzles, and greases and
tars are injected through side ports. Waste flow is countercurrent to the flow
of off gases* A typical multiple-hearth incinerator system is shown in Figure
1.
The furnace has three operating zones: the top hearths operate at tempera-
tures between 310 to 540° C (600 to 1000°F) and dry the sludge feed to about
487. moisture; the incineration/deodorizing zone operates at temperatures from
760 to 980° C (1400 to 1800°F); and the cooling zone, where hot ash is cooled
by giving up heat to incoming combustion air, operates at temperatures from
200 to 320°C (400 to 600°F).
Combustion air and combustion products flow vertically through the furnace
and exit at 260 to 540°G (500 to 1000°F). Exhaust gases normally pass through
an emission control system prior to discharge.
The ash remaining in the bottom hearth, depending on the material being
incinerated, is about 10% of the furnace feed and normally contains less than
1% combustible material. It is removed mechanically, hydraulically, or pneuma-
tically, and is normally disposed of in a landfill.
Rotary Kiln Incinerators
This type of incinerator is quite versatile and has been used in both
municipal and industrial installations. Municipal rotary kilns are generally
designed to incinerate large volumes of solid refuse and serve mainly as an
efficient mixer of air and wastes ignited on traveling grates prior to reach-
ing the kiln. Industrial rotary kilns are usually designed to incinerate both
liquid and solid wastes«. In the past, rotary kilns have been used to incin-
erate combustible solids (including explosives), liquids (including chemical
warfare agents), gases, tars, and sludges. Figure 2 shows a typical municipal
rotary kiln incineration facility, and Figure 3 shows a typical major indus-
trial rotary kiln facility which is operated by Dow Chemical Company at its
Midland, Michigan, planto
A rotary kiln used in large installations is a cylindrical, horizontal,
refractory-lined shell which is positioned on a slight incline. Solid waste
is fed into the upper end of the kiln, and liquid waste is fired horizontally
into the kiln. The kiln rotates with peripheral speed of rotation in the
range of 0.3 to 1.5 m (1 to 5 ft) per minute (typically 12 revolutions per
hour) and mixes the waste with combustidn air as the waste passes through the
kiln. The length-to-diameter ratio of these kilns usually varies from 2 to 10.
Typically these units are 9 m (30 ft) long and 3 m (10 ft) in internal diam-
eter (ID). The combustion temperatures normally range from 870 to 1650°C
(1600 to 3000°F), and residence times vary from a few seconds to several
hours, depending upon the type of waste.
11
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VACUUM
FILTERS
SLUDGES-
FILTRATE-*-
GREASE AND TARS
BURNERS
(FUEL OIL, GAS,
LIQUID AND GASEOUS WASTE)
AIR
AIR
WASTE AIR TO
ATMOSPHERE
CLEAN GASES TO
ATMOSPHERE
INDUCED
DRAFT FAN
SCRUBBERS
WATER
ASH TO
BLOWER DISPOSAL
ASH SLURRY TO FILTRATION AND
ASH DISPOSAL
Sources: Ottinger et al« (1973) and Scurlock et al. (1975)e
Figure 1. Multiple hearth incineration system.
-------
CHARGING
CHUTE
UNDERFIRE AIR DUCTS
TO EXPANSION CHAMBER
AND GAS SCRUBBER
RESIDUE CONVEYORS
Source: Ottinger et al. (1973).
Figure 2. Municipal rotary kiln incineration facility.
-------
s
TAR PUMPING
FACILITY
PACK STORAGE AND
FEEDING FACILITY
WATER SPRAYS
A
II' M.
SCRAP METAL
V FLY ASH
RESIDUE
Sources: Ottinger et al» (1973) and Scurlock et al. (1975).
Figure 3. Typical major industrial rotary kiln incineration facility.
-------
For example, a finely divided waste may require only 0.5 sec, while wooden
boxes, municipal refuse, and railroad ties may require 5, 15, and 60 min,
respectively.
Wet scrubber emission control systems are normally added to rotary kilns
used to dispose of hazardous wastes. Most kilns also have heat recovery equip-
ment to preheat combustion air or waste heat boilers for steam generation in
large installations.
Portable rotary kiln incinerators are currently marketed. An example of
this type of unit is the TUMBLE-BURNER, designed by Bartlett-Snow, shown in
Figure 4. This unit is not as versatile as large rotary kiln installations
since no pretreatment facilites for the waste are available. This requires
that the waste to be incinerated must be properly sized and relatively homo-
geneous. The unit can incinerate solid waste material with a heat content of
2.3 x 106 to 3.5 x 107 J/kg (1,000 to 15,000 Btu/lb) and can also incinerate
liquid and gaseous wastes when they are injected into the auxiliary burner
used for temperature control in the incinerator. The unit can incinerate be-
tween 45 kg (100 Ib) and 1.8 metric tons (MT) (2 tons) of waste per hour with
a corresponding system size of 1.5 x 1.5 x 4.6 m (5 x 5 x 15 ft) to 4.3 x
4.6 x 10.4 m (14 x 15 x 34 ft).
Examples of industrial facilities now in operation which process haz-
ardous wastes in a rotary kiln are: Dow Chemical Company at their Midland,
Michigan, plant; Minnesota Mining and Manufacturing Corporation at their
St. Paul, Minnesota, and Decatur, Alabama, chemical production complexes; and
Eastman Kodak's Rochester, New York, facility (in planning). These facilities
incinerate captive industrial wastes and do not normally accept wastes from
outside sources. Rollins Environmental Services, Inc., in Logan Township,
New Jersey, is an example of an incineration facility that accepts solid and
liquid chemical wastes for disposal in a system composed of a rotary kiln and
a liquid injection unit attached to a common afterburner.
Fluidized Bed Incinerators
This type of incinerator was first used commercially in 1962 for waste
disposal. These versatile units are capable of disposing of solid, liquid,
and gaseous combustible wastes. They have found limited use in the petroleum
and paper industries, in processing nuclear wastes, and for disposal of sani-
tary sludge. •
Figure 5 is a schematic diagram of a typical fluidized bed incinerator.
This unit operates by blowing air at a low velocity of about 1.5 to 2.0 m
(5 to 7 ft) per second up through a bed of inert granular particles (typically
sand) whose depth ranges from 38 cm (15 in.) to several meters. The air agi-
tates or "fluidizes" the bed and creates a dense, turbulent medium which
15
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1 WASTE TO INCINERATOR
2 AUTO-CYCLE FEEDING SYSTEM:
FEED HOPPER, PNEUMATIC FEEDER, SLIDE GATES
3 COMBUSTION AIR IN
4 REFRACTORY-LINED, ROTATING CYLINDER
5 TUMBLE-BURNING ACTION
6 INCOMBUSTIBLE ASH
7 ASH BIN
8 AUTO-CONTROL PACKAGE:
PROGRAMMED PILOT BURNER
9 SELF-COMPENSATING INSTRUMENTATION-CONTROLS
10 WET-SCRUBBER PACKAGE:
STAINLESS STEEL, CORROSION-FREE WET SCRUBBER; GAS QUENCH
11 EXHAUST FAN AND STACK
12 RECYCLE WATER, FLY-ASH SLUDGE COLLECTOR
13 SUPPORT FRAME
14 SUPPORT PIERS
15 AFTERBURNER CHAMBER
16 PRECOOLER
Sources: Ottinger et al. (1973) and Scurlock et al. (1975).
Figure 4. Portable rotary kiln incineration units.
-------
FLUE GAS
MAKEUP SAND
ACCESS DOOR
AUXILIARY
BURNER (OIL OR GAS)
v/
SAND BED
" " " "
i i
WASTE INJECTION
FLUIDIZING AIR
V
ASH REMOVAL
Sources: Ottinger et al. (1973) and Scurlock et al. (1975).
Figure 5. Schematic of a fluid!zed bed corabustor.
17
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behaves similarly to a liquid. Wastes are injected into the fluidized bed
pneumatically, mechanically, or by gravity. Bed material and the wastes are
rapidly and relatively uniformly mixed, and the mass of the fluidized bed is
large relative to the mass of the injected waste.
Heat is supplied by an auxiliary gas or oil burner to maintain the bed
temperature in the range of 760 to 870°C (1400 to 1600°F). At these tempera-
tures, the fluidized bed provides a large heat reservoir of about 6.0 x 10^
J/rn^ (16,000 Btu/ft3),-which i-s"three orders^of magnirtude greater than the
heat capacity of flue gases at similar temperatures in typical incinerators.
Heat is transferred from the bed into the injected waste materials, the waste
is rapidly combusted, and the heat of combustion is transferred back into the
bed. Large waste particles are kept in suspension by the fluidizing air until
they are completely incinerated. The residual fines (ash) are carried off with
the flue gas exhaust at the top of the incinerator. This exhaust gas may be
processed or scrubbed prior to atmospheric discharge by using fabric filters,
electrostatic precipitators, dry collectors, and wet scrubbers. The collected
ash is usually landfilled.
Wastes injected into a fluidized bed incinerator may require preprocess-
ing to facilitate the incineration process. Dewatering may be required to re-
move the moisture content, shredding may be required to make the waste more
homogeneous, and noncombustible materials (such as metals) may have to be re-
moved to prevent residual buildup in the bed.
The advantages of this type of incineration are that it is generally ap-
plicable to the disposal of solid, liquid, and gaseous combustible wastes; the
design is simple and requires no moving parts in the combustion regions; the
unit is compact due to high heat rates, which reduces capital cost; and rela-
tively low gas temperatures and excess air requirements minimize nitric oxide
formation, which could reduce emission control requirements and costs. The
disadvantages of this unit are that removal of residual material from the bed
is a potential problem; and temperatures in the bed cannot exceed the softening
point of the bed material to avoid softening and agglomeration of the material.
Examples of fluidized bed incinerators used to incinerate hazardous
wastes are the Liquid and Solid Waste (LSW) Disposal System of Combustion
Power Company located at Menlo Park, California, and the EPA demonstration
grant fluidized bed Incinerator located at the Franklin, Ohio, Resource Re-
covery Plant •
Liquid Injection Incinerators
This type of incinerator is quite versatile and can incinerate virtually
any combustible liquid waste. These units are widely used in manufacturing
industries and vary widely in operating conditions and applicability. Some
wastes currently disposed of in industry with these units are separator sludges,
18
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skimmer refuse, oily wastes, detergent sludges, digester sludges, cutting oils,
coolants, strippers, phenols, wine wastes, potato starch, vegetable oils,
washer liquids, still and reactor bottoms, soap and detergent cleaners, animal
oils and rendering fats, plating wastes, lubricating oils, soluble oils, poly-
ester paint, polyvinyl chloride (PVC) paint, latex paint, thinners, solvents,
polymers, resins, cheese wastes, inks, and dyes*
Operating conditions in liquid injection units vary widely. Temperatures
vary from 650 to 1650°C (1200 to 3000°F) with a typical temperature of 870°C
(1600°F), and residence times vary from 0.5 to 1.0 sec. Most units have a heat
release of approximately 9.3 x 108 J/hr-m3 (25,000 Btu/hr-ft3) with the ex-
ception of the Vortex Type Liquid Combustor which has an unusually high heat
release of about 3.7 x 109 J/hr-m3 (100,000 Btu/hr-ft3).
Liquid waste incineration requires atomization of the liquid and violent
turbulence and mixing of the droplets to effect rapid vaporization and good
combustion. The viscosity of the liquid is reduced by heating or mixing a low
viscosity liquid into the waste liquid. The liquid is then atomized by rotary
cup atomization or pressure atomization through a single orifice nozzle or
through a two-fluid nozzle, which may be an internal mix, external mix, or
sonic.type nozzle. Turbulent mixing is achieved in many cases by supplying a
forced draft to the combustion chamber.
Liquid injection incinerators are classified as horizontally fired or
vertically fired units. A typical horizontally fired liquid waste incinera-
tion system is shown in Figure 6, and a typical vertically fired system is
shown in Figure 7. The horizontal unit is one operated by Dow Chemical Com-
pany at their Midland, Michigan, plant. The vertical unit is one designed and
marketed by the Prenco Division of Pickands Mather and Company. Figure 8 shows
a unique type of unit called the Vortex combustor. It is unusual in that its
heat release capability is four times higher than the other type units.
The horizontally fired incineration system operates by feeding the waste
to the unit through a combination of four dual-fired nozzles. Combustion gases
pass through a spray chamber, a venturi scrubber, and a cooler/mist-eliminator
prior to exhaustion through a stack.
The vertically fired incineration system operates by first heating the
vertical retort up to the desired temperature with a mixture of high pressure
•air and auxiliary fuel. When the retort attains the proper temperature, the
waste is fed into the air waste entrainment compartment for aeration and then
into the turbulence compartment for mixing with high pressure air. The mix-
ture is then fed into the bottom of the vertical decomposition chamber where
the waste is broken down by oxidation, ionization, and molecular dissociation.
The combustion gases flow vertically through the air cone, which serves as a
fuel saver and an afterburner, and out the top of the retort.
19
-------
LIQUID WASTES FROM PLANT
SEPARATE TANKS FOR
STACK 100 FT. HIGH
6 FT. 6 IN. I. 0.
4 FT. 6 IN. I. 0. OUTLET
LINED WITH ACID-RESISTING
PLASTIC
o
'
S
o
rof
o
IAGE
i
»
MELTING-
STRAINER
I— \
~M
10
O
BURNING
TANK
WASTE-TAR
FEED
ATOMIZING
B LOWER
RELIEF
STACK
(CLOSED
DURING
OPERATION)
TEMPERING
AIR BLOWER
x-v 10,000
f O) CU. FT./MIN.
I p 25 HP.
VENTURI SCRUBBER LINED WITH
ACID. RESISTING PLASTIC
RECYCLED
WASTE
WATER
FRESHWATER \ 1,300 GPM.
300 GPM. i RECYCLED j
\ WASTE
v WATER
COMBUSTION AIR BLOWER
13,000 CU. FT./MIN.
75 HP.
TOTAL AIR, 26 LB./LB. WASTE
| U. TEMPERING
)AIR BLOWER
10,000
CU. FT MIN.
25 HP.
WATER
2,300 GPM.
PH 1.0
INDUCED-DRAFT FAN
2,600 LB. MIN.
45,000 CU. FT. 'MIN.
600 HP.
WATER
240 GPM.
pH 1.0
WASTE TAR FEED: AVG. 10 GPM.
13,00 BTU. 'LB. '
TEMPERATURE 80-1000C.
VISCOSITY 150 SSU.
5 PSI FEED
4 BURNERS, COMBUSTION
GAS AND TAR NOZZLES
5/16 - IN.ORIFICE
Source: Ottinger et al. (1973).
Figure 6» Horizontally fired liquid waste incineration system^
-------
EFFLUENT DIRECTLY TO ATMOSPHERE
OR TO SCRUBBERS AND STACK
FRFE STANDING
INTERLOCKING REFRACTORY
MODULES
TEMPERATURE MEASURING
INSTRUMENTS
UPPER NACELLE
TURBO-BLOWER
IGNITION CHAMBER
HIGH VELOCITY
AIR SUPPLY
AIR-WASTE ENTRAINMENT
COMPARTMENT
WASTE LINE
FRESH AIR INTAKE
FOR TURBO-BLOWER
AND AFTERBURNER FAN
AIR CONE
DECOMPOSITION CHAMBER
DECOMPOSITION STREAM
AFTERBURNER FAN
FLAME SENSITIZER
TURBULENCE COMPARTMENT
LOWER NACELLE
AUXILIARY FUEL LINE
TUBULAR SUPPORT COLUMNS
'UfCTRICAL POWtR LINE
Sources: Ottinger et al. (1973) and Scurlock et al. (1975).
Figure 7. Typical vertically fired liquid waste incinerator.
21
-------
ANNULAR SPACE FILLED
WITH AIR UNDER
PRESSURE FOR TUYERES
BAFFLE SHELL
AIR TUYERES
EFFLUENT TO SCRUBBERS
AND STACK
REFRACTORY WALL
TUYERE AIR SHELL
AND PLENUM
REFRACTORY WALL
COOLING AIR PORTS
CAST IN REFRACTORY SLAB
AIR TUYERES
COMBUSTION AIR
TO TUYERES
REFRACTORY
COOLING AIR
COMBUSTION
AIR
BURNER
NOZZLE
GAS BURNER
RING
COOLING AIR
(FORCED DRAFT)
TUYERE AIR SHELL
BAFFLE SHELL
Sources: Ottinger et al» (1973) and Scurlock et al» (1975).
Figure 8. Vortex liquid waste incinerators.
22
-------
The exhaust gases are reduced to 340° C (650°F) by the air cone and can be
passed through scrubbers if desired. These incineration systems operate be-
tween 870 and 1650°C (1600 and 3000°F).
The Vortex combustor is a cylindrical furnace in which the liquid waste
is fired tangentially by a modified oil burner into the bottom of the igni-
tion chamber. Tangential firing creates a vortex of hot gases which flow up-
ward through the combustion chamber, which is preheated to 430 to 540°C (800
to 1000°F) for 1 hr prior to injecting the wastes. Preheated high velocity
secondary air is introduced from tangential tuyeres to maintain the vortex as
the gases rise in the unit. Operating temperature ranges between 650 and 870°C
(1200 and 1600°F) with 20% excess air.
An example of liquid injection incinerator facilities used in central
disposal operations of hazardous wastes is Rollins Environmental Services,
Inc., at Bridgeport, New Jersey. The General Electric plant at Pittsfield,
Massachusetts, and the Dow Chemical Company plant at Midland, Michigan, process
in-house wastes with liquid injector incinerators. TRW Systems has developed
a liquid injection incinerator capable of high destruction efficiencies and
short dwell times for some pesticides, and the Marquardt Company of Van Nuys,
California, developed the Sudden Expansion (SUE® ) burner. Liquid injection
type incinerators have also been placed on ships for shipboard incineration
of liquid wastes. Two examples are the ships Vulcanus and Mathias III.
Multiple-Chamber Incinerators
This type of incinerator is used to dispose of most forms of combustible
municipal and industrial solid wastes, such as garbage, general refuse, wood,
paper, rubber, wire coatings, phenolic resins, acrylic resins, epoxy resins,
and PVC. Its normal application is limited to solid wastes.
There are two types of multiple-chamber incinerators: the retort type
(shown in Figure 9) and the in-line type (shown in Figure 10). Each type con-
sists of three separate chambers; an ignition chamber, a downdraft or mixing
chamber, and an up-pass expansion or secondary combustion chamber. Solid wastes
are fed to the ignition or primary chamber where they are dried, ignited, and
combusted into gases and particulates. These products pass into the mixing
chamber where secondary air is introduced. The gases are mixed when passed .
through restricted flow areas, subjected to abrupt changes in flow direction,
and expanded and contracted in ducts and chambers. The combustion products
then flow into the secondary combustion chamber where combustion is completed,
and exhaust gases are emitted through a stack or a combination of gas cooler
and induced draft system. The ash is collected in the combustion chamber by
wall impingement and settling and is removed through ports in the chamber.
23
-------
SECONDARY
AIR PORTS
SECONDARY
COMBUSTION
CHAMBER
KJ
CURTAIN
WALL PORT
CLEANOUT
DOOR
MIXING
CHAMBER FLAME PORT
IGNITION
CHAMBER
CHARGING DOOR
WITH OVERFIRE
AIR PORT
GRATES
CLEANOUT DOOR
WITH UNDERGRATE
AIR PORT
Source: Ottinger et al. (1973).
Figure 9. Retort multiple chamber incinerator.
-------
IGNITIONJ FLAME
CHAMBER
CHARGING DOOR
WITH OVERFIRE
AIR PORT
to
In
GRATES
PORT
SECONDARY
AIR PORT
.CURTAIN WALL
SECONDARY
COMBUSTION
CHAMBER
CLEANOUT DOORS WITH
UNDERGRATE AIR PORTS
LOCATION OF
SECONDARY
BURNER
MIXING
CHAMBER
Sources: Ottinger et al»
CLEANOUT
DOORS
(1973) and Scurlock et al. (1975).
CURTAIN
WALL PORT
Figure 10. In-line multiple chamber incinerator.
-------
Supplementary gas burners are not generally required when the moisture
content of the solid waste is less than 10%. Moisture contents of 10 to 20%
usually require the addition of gas burners in the mixing chamber, and mois-
ture contents above 20% usually require additional burners in the ignition
chamber*
The average temperature of the combustion products is 540°C (1000°F).
This temperature is low for the destruction of most pesticides although it can
be increased through the use of proper construction materials and additional
supplementary gas burners*
RESEARCH AND DEVELOPMENT
Various organizations have conducted research on the disposal of pesti-
cides by incineration. Some of the research and development work has been
done on a laboratory or pilot scale, while other efforts have been directed
towards incinerating pesticides in commercial or industrial scale operations.
This section of the report gives brief descriptions of research and develop-
ment programs—laboratory- and pilot-scale research and commercial or indus-
trial scale research—and summarizes the results of these programs.
Research and Development Programs
Laboratory and Pilot-Scale Research--
Mississippi State University--Investigators at Mississippi State Univer-
sity (MSU) conducted a series of pesticide disposal studies for the U.S.
Department of Agriculture between 1967 and 1975. These studies have resulted
in a number of published papers, as well as a series of unpublished grant re-
ports. The objectives of the first study were to make laboratory determina-
tions of the combusting temperatures and volatile off-gases of 20 analytical
grade pesticides, 20 of the most commonly used formulations of these pesti-
cides, and 8 types of pesticide containers; to determine the design require-
ments for readily combustible pesticide containers; and to develop specifica-
tions for an incinerator to dispose of pesticides and containers. The second
study involved incinerating the same pesticides and containers in laboratory
furnaces and a pilot plant incinerator to determine the respective burning
parameters of the pesticides and containers established in the laboratory
tests and to study scrubbing techniques to remove the toxic off-gases from the
effluent gas stream. A third study involved determining the thermal degrada-
tion products of additional pesticides (Holloman et al., 1975; Holloman et al.,
1976; Kennedy et al., 1969; Kennedy et al., 1972a; Kennedy et al., 1972b;
Stojanovic et al., 1972a; and Stojanovic et al., 1972b.)
In the first study three different methods of laboratory incineration or
thermal treatment were used; differential thermal analysis, dry combustion,
and ashing in a muffle furnace. The 20 pesticides investigated represented a
26
-------
wide range of chemical compounds and included 13 herbicides, 4 insecticides,
2 fungicides, and 1 nematocide (both the analytical grade pesticides and
their most commonly used formulations). The 20 pesticides were: 2,4-D,
picloram, atrazine, diuron, trifluralin, bromacil, DSMA, DNBP, dicamba,
dalapon, paraquat, vernolate, 2,4,5-T, carbaryl, DDT, dleldrin, malathion, PMA,
zineb, and Nemagon®. The pesticide containers investigated were: milk cartons,
clear polyethylene, amber polyethylene, polyethylene, PVC, Teflon™, and metal.
Differential thermal analysis showed that the combustion temperatures of
the pesticides were well within the range of temperatures attainable in conven
tional incinerators* The analytical grade pesticides were completely incin-
erated from about 250 to 879°C (480 to 1610°F); 15 of the compounds were com-
pletely combustible at 700°C (1290°F) or below, while 5 required 700 to 900°C
(1290 to 1650°F). The commercial formulations required about the same tempera-
ture range, 508 to 852°G (950 to 1565°F), and dalapon, trifluralin, and
Nemagon® required higher temperatures than the respective analytical grade
compounds .
Dry combustion of the analytical grade pesticides at 900°C (1650°F) re-
vealed that, on the average, 10% of the carbon is not accounted for as
. When the commercial formulations were incinerated, all but six formula-
tions approached complete combustion at 800°C (1470°F)« Atrazine, bromacil,
carbaryl, and dalapon contained 10% of uncombustible residue at 1000°C (1830°F),
while DSMA and zineb yielded 19 and 23% ash, respectively, at 1000°C (1830°F).
Analyses of the volatile products of the 20 pesticides Incinerated at 900°C
(1650°F) revealed that carbon dioxide, carbon monoxide, chlorine, hydrogen
chloride, hydrogen sulfide, nitric acid, nitrogen oxides, and residues of in-
organic compounds were produced*
The investigators concluded that pesticides could be disposed of by in-
cineration but that further work was required to provide suitable scrubber
technology to remove the toxic gases from the effluent gas stream.
A second study was conducted in which, the same pesticides and containers
were incinerated in the laboratory in one or two resistance-type furnaces con-
nected in series and in a model incinerator equipped with a flue gas scrubber
system. Incineration in both the laboratory and the model incinerators was
accompanied by tests to determine the kinds and quantities of corrosive in-
organic gases emitted and to determine the kinds of gas scrubbing or gas
trapping systems needed for the various gases emitted. The emission gases
analyzed were carbon monoxide, carbon dioxide, chlorine, hydrogen chloride,
ammonia, nitrogen oxide, hydrogen sulfide, sulfur dioxide, and various oxi-
dants. Many substances were tested as scrubbing and absorbing agents for
chlorine, hydrogen chloride, hydrogen sulfide, sulfur dioxide, and carbonyl
sulfide* and included acidic solutions, alkaline solutions, solid alkalies,
and various mixtures. The significant findings of the study were:
27
-------
* Incineration of chlorinated pesticides at 900°C (165CPF) produced both
free chlorine gas and hydrogen chloride*
* Incineration of DDT at 900° C (1650°F) produced emission of chlorine,
hydrogen chloride, and oxides of chlorine in a ratio of 1:6:3.
* Incineration of nitrogen-containing compounds at 90(Pc (165CPp) pro-
duced ammonia in the emissions*
* Incineration of sulfur-bearing pesticides, specifically thiocarbamates
and organophosphates, at 90tf*C (165tf*F) produced sulfur dioxide and
hydrogen sulfide.
* Catalysts (molybdic anhydride, cupric sulfate, lignin, and humic acid)
reduced the temperatures necessary to "crack" and detoxify the pesti-
cide molecules when added to the pesticides during incineration*
* Halogen-, sulfur-, and nitrogen-containing gases were effectively
scrubbed from the incinerator effluent gas with solutions of metal
hydroxides (sodium and potassium)*
* Sulfur dioxide was most effectively scrubbed by sodium hydroxide solu-
tions*
* Solid potassium carbonate effectively scrubbed halogens from the
effluent gas but would be too corrosive to use in an incinerator*
* Neutralization of halide-scrubbing solutions prior to landfill re-
leased the halogens and would be both impractical and prohibitive be-
cause of the air pollution which could result*
The third study conducted by MSU, concluded in 1975, investigated the
thermal degradation of selected pesticides. In one segment of the study, the
thermal degradation products of mirex were determined at temperatures be-
tween 525 and 70tf*C (975 and 1290PF). The investigators found that the gaseous
products included carbon monoxide, carbon dioxide, hydrogen chloride, chlorine,
carbon tetrachloride and phosgene, and the residue contained mostly hexachloro-
benzene with traces of hexachlorocyclopentadiene* In another segment of the
study, the gaseous products of three chlorinated herbicides—chloramben,
linuron, and propanil—were determined for incomplete combustion at 400^0
(75CPF). Gases identified included HCN, NO, CH3NH2» HCl, N02, CH3Cl, C2H3Cl,
and C2H5C1. The investigators concluded that these gases would have to be
scrubbed from the effluent stream before incineration would be an acceptable
method for disposal of chlorinated herbicides.
28
-------
Midwest Research Institute--Midwest Research Institute (MRI), Kansas
City, Missouri, designed and constructed an experimental incineration system
to evaluate the effect of operational variables (rate of pesticide injection,
percent excess air, operating temperature, and retention time) on the ef-
ficiency with which organic pesticides can be incinerated. This system in-
cluded a pilot-scale incinerator (45.4 kg/hr (100 Ib/hr) Type 1 waste* capac-
ity), a three-stage scrubber, and a scrubber water treatment system. Nine
pesticides in 15 liquid and solid formulations were tested by injection into
the primary combustion chamber. The pesticides studied were DDT, aldrin,
picloram, malathion, toxaphene, atrazine, captan, zineb, and mirex (Ferguson
et al., 1975).
Results of the incineration tests were evaluated in terms of the effi-
ciency of AI destruction, i.e., the percent of the pesticide destroyed within
the combustion chamber. Over a range of combustion chamber, retention time,
temperature, and excess air rate combinations, efficiencies of greater than
99.99% were achieved for all pesticides tested except mirex. Test results
were used to estimate stack emission rates for the subject pesticides when in-
cinerated at 1000°C (1832°F) with 2-sec retention time.
A set of operating conditions (temperature, retention time, and excess
air rate) was developed from comparable results for all 15 formulations; the
set is believed to be applicable to the incineration of most organic pesti-
cides.
Analysis of the incinerator effluents also showed that high concentrations
of sulfur dioxide and cyanide were present when organosulfur and organonitrogen
pesticides, respectively, were incinerated under certain operating conditions.
Particulate loadings in the effluent gases during the incineration of solid
pesticide formulations (dusts, wettable powders, granules, and pellets) were
above federal limits established for new stationary sources having a capacity
of or greater than 45,000 kg/day (50 tons/day). Thus, the investigators con-
cluded that particulate emission control devices will be required for pesti-
cide incinerators. ;
University of Dayton Research Institute (UDRl), Dayton, Ohio—Investi-
gators at UDRI developed a specialized laboratory technique that could quickly
and economically evaluate a pesticide's destruction characteristics within
minimal environmental risk. The technique consisted of a two-step destruction
process which first vaporized the pure pesticide at a low temperature of 200
to 300°C (390 to 570°F) and then passed the gas phase sample through a
Type 1 waste is defined as rubbish, a mixture of combustible waste such as
paper, cardboard cartons, wood scrap, foliage and combustible floor sweep-
.ings, from domestic, commercial and industrial activities. This type of
waste contains 25% moisture, 10% incombustible solids and has a heating
value of 1.51 x 107 J/kg (6,500 Btu/lb).
29
-------
high-temperature quartz tube. The advantages of this technique were precise
control and measurement of the critical parameters of temperature and resi-
dence time; the capability of evaluating the thermal destruction of pesticides
on the molecular level; and the use of pure pesticides to remove interferences
from other materials. This technique has been found to be a substantial advance-
ment in the state of the art of pesticide incineration research since results
from experiments on the thermal destruction of pesticides are reproducible
(Duvall and Rubey, 1976).
Laboratory tests were conducted to evaluate the high temperature destruc-
tion of Kepone®, DDT, and mirex. Results of the tests showed that Kepone® and
DDT were essentially destroyed at 500°C (930°F) and a residence time of 1 sec,
while mirex required 700°C (1290°F) for destruction at the same residence
time. At a temperature of 900°C (1650°F), the destruction efficiences were:
Kepone®> 99.9995%, DDT > 99.9980%, and mirex, > 99.9998%. Effluents from these
tests contained two major decomposition products: hexachlorocyclopentadiene
(HCPD) and hexachlorobenzene (HCB). The first product was present in the 400
to 600°C (750 to 1110°F) range, while HCB was present in the 500 to 900°C
(930 to 1650°F) range.
United States Army Land Warfare Laboratory, Aberdeen Proving Ground^
Maryland--A study was performed to provide local post engineer organizations
with an acceptable method for disposing of small quantities of DDT-kerosene
mixtures. The system devised was simply a 208-liter (55-gal.) drum lined with
a refractory material (Fiberfrax®) and open at one end, an oil burner, and
a scrubber system constructed from a shower head. The 208-liter (55-gal.) drum
served as the furnace, and the gases were passed through a scrub tower contain-
ing the shower head and a scrubber ring. The scrubber water was neutralized
by running it over limestone (Rosen, 1974).
This simple system was capable of burning 19 liters (5 gal.) of DDT-
kerosene solution per hour. Sampling and analyses of the stack gases for total
hydrocarbons, opacity, C02, 02, N2, CO, particulates, hydrochloric acid, and
residual DDT, and tests for residual DDT and hydrochloric acid in the scrubber
water were conducted by the Army Environmental Hygiene Agency. These tests
showed that the emissions from burning DDT in this manner were below the com-
bustion emission standards established by the State of Colorado. DDT was
99.9999+% destroyed at 'a temperature of about 1400°C (2550°F) with a dwell
time of 3 sec.
Foster D. Snell, Inc., Florham Park, New Jersey—This company conducted
a study to investigate the disposal of pesticides and pesticide containers by
30
-------
combustion in the field;**/ the effect of oxidizers and binding agents on pes-
ticide combustion; the combustion characteristics of container materials; and
the possible use of special liners to assist the combustion of the pesticides
and containers (Putnam et al., 1971).
Prior to the open field combustion studies, laboratory studies were con-
ducted to determine the combustion and decomposition characteristics of several
pesticides. The decomposition products of DDT and malathion were determined
at various temperatures, with and without the use of oxidizing agents, in a
pyrolysis unit. A differential scanning calorimeter was used to determine the
decomposition characteristics of DDT, maleic hydrazide, aldrin, dalapon,
Diazinon®, malathion, carbaryl, PCNB, aminptriazole, and atrazine when heated
alone, in the presence of oxidizers, or in the presence of binders, in both
closed and open systems. Oxidizers tested included potassium chlorate, potas-
sium nitrate, sodium nitrate, and others. Binders tested included mineral oil,
paraffin wax, polyethylene, and others.
These tests showed that polyethylene and mineral oil are satisfactory
binding agents and significantly increase the amounts of some pesticides
(carbaryl, DDT, PCNB, and aldrin) that decompose at 300° C (570°F) but have
little effect on the decomposition of other pesticides (Diazinon®, mala-
thion, and atrazine). The tests also showed that the addition of potassium
chlorate to carbaryl, PCNB, or DDT increased the amount of pesticide decom-
posed at 300°C (570°F) but has no effect on aldrin, Diazinon®, malathion, or
atrazine.
Tests were then conducted to determine the combustion characteristics
of pesticides burned in an open field. Pesticides were placed in polyethylene
bags, surrounded by Kraft paper or cardboard, and burned. DDT, aldrin,
dalapon, Diazinon®, malathion, carbaryl, maleic hydrazide, PCNB, atrazine,
2j4-D, MH-30, and aminotriazole were tested in this manner.
The investigators concluded that pesticides may be 99% or more destroyed
by combustion at temerature of 500 to 690°C (930 to 1270°F) achieved by burn-
ing wood, paper, cardboard or plastics; that binding agents aid combustion of
the pesticide by retaining it; that oxidizing agents lower the temperature
necessary for complete combustion and aid oxidation; and that the combustion
gases emitted are mainly carbon dioxide, carbon monoxide, sulfur dioxide,
chlorine, ammonia, hydrogen sulfide, hydrogen chloride and phosgene, depending
upon the pesticide burned.
Canadian Defence Research Council, Suffield—This organization inciner-
ated DDT during the period 1971 to 1973 in its Thermal Destructor in Ralston,
Alberta (Scurlock et al., 1975). The Thermal Destructor was designed by
£/ Open burning of pesticides or pesticide containers is not recommended by
EPA (see Appendix B).
31
-------
Pyrotherm Equipment Ltd*, of Burlington, Ontario, to incinerate chlorinated
hydrocarbons like DOT with provisions also to incinerate sulfur compounds* It
consisted of a horizontal cylindrical combustion chamber, a dual-fired (natural
gas and oil) burner installed in one end, and a vertical cylindrical scrub-
bing tower installed on the other end to remove HCl from the exhaust gases*
The operating temperature in the combustion chamber was held at 900° C (1650°F)
to incinerate the DDT and operated at a DDT feed rate of 380 liters (100 gal.)
per hour (Montgomery et al*, 1971).
A total of 708,000 liters (187,000 gal.) of 5% DDT/kerosene solution was
destroyed in the incinerator* Test results showed that 99.9998 to 100.0% of
the DDT was destroyed in the Thermal Destructor operation. Using the lower
figure, it was estimated that < 0.065 kg (2.3 oz) of DDT remained undestructed
during incineration of the entire quantity (Scurlock et al., 1975, and
Montgomery et al., 1971).
Powders containing 10, 50, and 92% DDT were also incinerated in this unit
at feed rates of 15 kg/hr (33 Ib/hr), 5.5 kg/hr (12 Ib/hr), and 5.5 kg/hr (12
Ib/hr), respectively. Analyses of the scrubber water showed that the DDT con-
centration was < 0.01 ppm and the DDE concentration was < 0.001 ppm during
normal operating conditions. DDT deposits were < 0.1 ppm and DDE deposits were
< 0.03 ppm in the waste heat boiler when the powder containing 92% DDT was
burned (Lee et al., 1971).
TRW Systems, Inc., Redondo Beach, California—TRW conducted a laboratory-
scale incineration study for the U.S. Army from 1973 to 1975 (Shih et al.,
1975). A total of 11 individual pesticide formulations and 3 mixed pesticide
formulations were incinerated in a liquid injection-laboratory-scale incin-
erator. This system consisted of an injector assembly that included a com-
pressed air-driven fuel atomizer, a combustion chamber, an afterburner section,
a quench chamber, and a packed-bed wet scrubber for removal of particulates
and hydrogen chloride. The individual pesticide formulations investigated were
DDT (5% oil solution, 20% oil solution, 25% emulsifiable concentrate (EC),
and 10% dust), lindane (1% dust and 12% EC), dieldrin (15% EC), chlordane (5%
dust), 2,4-D liquid ester, and 2,4,5-T liquid esters.
Experimental data collected focused on the optimal temperatures, air-
to-pesticide supplementary fuel ratios, furnace residence times, combustion
products, and destruction efficiency. The data indicated that the mean de-
struction efficiency for the pesticide Al was > 99.9975% when the conditions
for complete combustion of the pesticide formulations were attained. For most
pesticide formulations investigated, a minimum of 0.4 sec residence time at
temperatures in excess of 1000°C (1832°F) and excess air in the range of 45
to 60% were found to be necessary for complete destruction of the pesticides.
The combustion chamber refractory liners were not significantly affected dur-
ing the tests, and burning dust formulations did not result in significant
agglomeration or breakdown of the dust particles.
32
-------
The incineration tests revealed that the major equilibrium products of
combustion were C02, H20, HCl, N£> and Q£ when the incinerator temperature
ranged between 540 and 1370° C (1000 and 2500°F) with 30% excess air present.
Essentially all of the chlorine present in the pesticide formulations was con-
verted to HCl.
Chemagro, Division of Mobay Chemical Corporation, Kansas City, Missouri—
Chemagro designed and patented a mobile unit to decontaminate and recycle metal
pesticide containers (U.S. Patent No. 3,701,355). The unit consisted of a shred-
der, incinerator, afterburner, and gas scrubber mounted on the flatbed of a
truck, trailer, or train car. Spent metal pesticide containers would be shredded
to nugget-sized (2.5 cm or 1 in. diameter) pieces and incinerated at about 540
to 700°C (1000 to 1300°F) to burn off all organic residual matter on the metal.
Combustion air for the incinerator would come from the large volume of
pesticide-contaminated air generated by the shredding operation. The combus-
tion gases from the incinerator would then pass through the afterburner
(1000°C or 1830°F) and the gas scrubber to decontaminate the gas prior to dis-
charge into the atmosphere. A conceptual drawing of the disposal unit is shown
in Figure 11.
In viewing Figure 11, it is important to note that the design was never
built and tested as a total disposal unit; only portions of the unit were in-
dividually operated to confirm overall feasibility and to estimate the op-
erating performance characteristics.
Chemagro tested the concept by processing a series of 19-liter (5-gal.)
cans and 114-liter (30-gal.) and 190-liter (50-gal.) drums, which had contained
disulfoton liquid concentrate, through the shredder and an incinerator. The
incinerator was operated at about 650°C (1200°F) and the residence time was
4 min. The scrap metal recovered contained less than 1 ppm disulfoton in com-
parison to a contamination of about 10,000 ppm on the metal containers.
The project has not been active since 1975 because Chemagro Agricultural
Division of Mobay Chemical Corporation is not interested in. experimenting,
developing, or commercializing the unit at the present time; but they would
be willing to license the technology to interested parties (Scott, 1977).
The Marquardt Company, Van Nuys, California—This company incinerated DDT
in solution, Herbicide Orange, and hydrazine in their SUlf® burner developed
14 years ago as a source of high temperature, high pressure air for testing
air-breathing ramjet engines. The Marquardt Company has sold about 50 units
with operating temperatures ranging from 540 to 3150°C (1000 to 5700°F), and
currently markets a SUE^S) burner as a liquid waste disposal system (Scurlock
et al., 1975).a/
£/ SUE^1 burners are available on special order for specific applications
(Babbitt, 1978).
33
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Storage
Bin
Containers to
be Reclaimed
Conveyor
to Truck
Source:
U.S. Patent No. 3,701,355
Chemagro Agricultural Division
Mobay Chemical Corp.
Conveyor to
Shredder
Containers to
be Reclaimed
Figure 11. Conceptual drawing of a mobile metal pesticide container disposal unit.
-------
The apparatus used in the pesticide tests consisted of a SUE® burner
incinerator and reaction tailpipe, and a venturi scrubber and scrubber collec-
tion tank. The system was preheated with natural gas and combustion air, and
the temperature was maintained by using the herbicide formulations as combus-
tion fuel during incineration. The scrubber water injected into the venturi
scrubber contained about 12% by weight NaOH to neutralize the HCl formed in
the incinerator. Combustion exhaust gases leaving the reaction tailpipe passed
through the venturi scrubber before being exhausted to the atmosphere (Riley,
1975).
One drum each of 5 and 20% DDT solution was incinerated for the Department
of the Army, and test results showed that chlorinated hydrocarbons were not
detectable in either the combustion gases or scrubber water. The system was
operated at tailpipe exit temperatures of 1090°C (2000°F) and a residence
time of 0.14 sec (Scurlock et al., 1975).
During the period 1972 through 1973, Marquardt incinerated Herbicide
Orange for the Department of the Air Force. Twenty-eight 208-liter (55-gal.)
drums were destructed at temperatures ranging from 975 to 1370°C (1760 to
2500°F) at residence times ranging from 0.14 to 0.18 sec. The system could
accept 150 liters (39 gal.) per hour. When the system was operated at tempera-
tures between 1230 and 1370®C, (2250 and 2500°F) the destruction efficiency
was 99.980 to 99.999%. The scrubber water contained dichlorophenol, 2,4-D,
2,4,5=1} aliphatic hydrocarbons, and a biphenyl compound but did not contain
dioxin (Riley, 1975; Scurlock et al., 1975| and Munnecke et al., (1976).
Hydrazine was incinerated in the unit during this same period at tempera-
tures of 690°C (1270°F) and 1225°C (2240°F) with a retention time of 20 sec.
Hydrocarbons in the combustion gas effluent were less than 10 ppm. Destruc-
tion efficiencies for hydrazine were not reported (Riley, 1975).
MB Associates, Inc., San Ramong California—This company is currently de-
signing a mobile thermal detoxification system for destroying hazardous wastes
under EPA Contract No. 68-03-2515. The system consists of a rotary kiln fol-
lowed by an afterburner followed by gas stream cleaning equipment utilizing in-
duced draft in order to avoid vapor and dust leakage at seals and connections.
Heat energy is supplied by oil-fired burners in the kiln and afterburner
(Tenzer, 1978).
The 132 cm (52 in.) ID by 5 m (16 ft) long kiln can be fed solids by
means of a ram stoker, or sludge and liquids by means of a positive displace-
ment pump system. Solids are first shredded in a shear-type shredder which
is capable of shredding 55-gal. steel drums, small logs, and steel belted
radial tires. The kiln is being designed for direct firing and includes
standard heat transfer mixing chains. The refractory lining has been selected
for thermal cycling, heat resistance, corrosion resistance, and over-the-road
capability.
35
-------
FIBERGLASS FILTER ROLL
PARTICLE SCRUBBER
QUENCH WATER
SEPARATOR & SUMP
MASS TRANSFER PACKED
TOWER SCRUBBER
STACK AND WINCH
NOT SHOWN FOR
CLARITY -,
CONTROL
PANEL
AND
OPERATOR
STATION
EXHAUST GAS OUTLET
BLOWER DIESEL ENGINE
DIESEL
GENERATOR
HYDRAULIC
RAM
BREACHING AND CROSSOVER
DUCTING
Source: Tenzer (1978).
Figure 12. Artistic rendering of mobile rotary kiln for disposal of hazardous wastes.
-------
The refractory-lined afterburner is sized for the optimum kiln throughput
of hazardous materials in soil with 10% moisture. It will be a tubular unit 132
cm (52 in.) ID by 11 m (36 ft) in length* The design incorporates road shock
considerations by utilizing rubber in shear supports as well as air ride sus-
pension on the trailer.
The gas stream cleaning equipment includes both particle and mass transfer
scrubbing equipment necessary to control P2®5 from organic phosphates and SC>2
from sulfur-bearing compounds.
The operating parameters of the design are:
Kiln - 815 to 980°C (1500 to 1800°F)
1 hr residence time for solids
Afterburner - 1100°C (2012°F) minimum temperature
2 sec gas residence time
Gas effluent - P205 - maximum permanent plume opacity - 10%
SC>2 - 200 ppm maximum
HCl - 200 ppm maximum
Feed rates - 1,361 kg/hr (3,000 Ib'/hr) hazardous material
bearing soil with 10% moisture
A preliminary artist's rendering of the proposed system is shown in Figure 12.
Design details are still under development.
Commercial/Industrial Scale Incineration--
Versar, Inc»°-This company conducted a two-phase study to demonstrate that
DDT and 2,4,5-T could be destroyed in a sewage sludge incinerator (Whitmore,
1975). In the first phase, DDT powder (75% AI), DDT in kerosene <"20% Al), and
Weedon® solution (20% 2,4,5-T), were incinerated in a 76-cm (30-in.) six-hearth
pilot-scale furnace operated by Envirotech Corporation at Brisbane, California.
The pesticides were mixed with sludge containing about 20% by weight solids
in the ratio of 0.02 g/g and 0.05 g/g pesticides to sludge. Incineration was
conducted on all the pesticides with the afterburner at 760°C (1400°F), at
955°C (1750°F), and shut off. Results showed that the destruction efficiencies
of 2,4,5-T were above 99.95% with and without the afterburner operating. In
almost all cases the highest pesticide losses (including DDT, ODD, DDE, and
2,4,5-T) were in the scrubber water. No tetrachlorodioxin was detected in the
2,4,5-T formulation or in the incinerator off-gas.
In the second phase, the same type of pesticide formulation was inciner-
ated in the municipal sewage sludge incinerator at Palo Alto, California, under
normal operating conditions (which includes an afterburner). Destruction effi-
ciencies were 99.97% or higher for DDT (including ODD and DDE) at an average
37
-------
hearth temperature of about 635° C (1175°F) and an afterburner temperature of
about 650°C (1200°F); they were 99.99% or higher for 2,4,5-T at an average
hearth temperature of about 690°C (1275°F) and an average afterburner tempera-
ture of about 660°C (1220°F). DDE and ODD were both formed during DDT incinera-
tion, but no dioxin was detected during the 2,4,5-T incineration tests. The
destruction efficiencies reported were conservative since most of the undestroyed
pesticides and their derivatives were found in the scrubber water, which was
returned to the plant for recycling.
The report concluded that DDT and 2,4,5-T can be safely destroyed by co-
incineration with sewage sludge in a multiple hearth furance and that the in-
ternal hearth temperatures should be maintained in excess of 550 to 600°C
(1000 to 1100°F) in order to minimize the formation of DDE.
Midland-Ross Corporation Surface Division, Toledo, Ohio—This company in-
cinerated small amounts of Kepone®(4 kg maximum sample size) mixed with sewage
sludge from January through March 1977. Some 8,553 g (18.85 Ib) were vaporized
and then thermally destroyed at a temperature of 1100°C (2000°F) with a resi-
dence time of 2 sec. The major decomposition products were C02, H20, and
sodium chloride, with small amounts of HCl and traces of hexachlorobenzene.
The destruction efficiency exceeded 99.99% for Kepone®. The final report of
the tests will be available during the summer of 1978 (Games, 1977j Chemical
and Engineering News, 1977a; and Chemical Engineering, 1977).
The State of Virginia recently authorized Flood and Associates of
Jacksonville, Florida, to develop a Kepone® facilities plan as required by
Section 201 of P.L. 92-500. This plan will provide for an incinerator to de-
stroy 45,000 kg (100,000 Ib) of Kepone®.
General Electric Company (GE)--GE incinerated a 20% liquid DDT formula-
tions in a liquid injection-type incinerator located at its Pittsfield,
Massachusetts, plant during September 1974 (Leighton and Feldman, 1975). The
incinerator is a Vortex combustor normally used for the disposal of waste oils
and solvents from the plant manufacturing operations. The facility, which was
manufactured by John Zink Corporation, consists of a horizontally mounted
cylindrical combustion and oxidation chamber followed by a water spray
quench pot, a countercurrent packed scrubber column, and a stack. Combustible
liquid wastes are injected into the combustion chamber through two steam at-
omizing nozzles in a way that creates a vortex-type turbulence to produce a
high heat release, longer retention time, and complete combustion. After com-
bustion, the waste gases pass through the oxidation chamber which operates at
870 to 980°C (1600 to 1800°F) at residence times of 1 to 12 sec. The gases are
then cooled in the quench pot with water sprays, passed through the packed bed
scrubber column, and exhausted through the stack.
Twenty-eight, 208-liter (55-gal.) drums of a 20% liquid DDT formulation
were incinerated in the GE incinerator. Two feed rates, 1989 liters/min
38
-------
(0.5 gal/rain) and 3.03 liters/min (0.8 gal/min), and two operating temperatures,
870°C (1600°F) and 980°C (1800°F), were used. Residence time varied from 3 to
4 sec, and excess air ranged from 120 to 160%. Concentrations of DDT, DDE, and
ODD in the stack gas and scrubber water were below the limits of sensitivity
of the analytical methods used during the tests, and the destruction efficiency
exceeded 99.9999% in all of the tests.
Shell Chemical Company, Deer Park, Texas—The first officially sanctioned
incineration at sea by the United States was conducted by Shell Chemical Company,
Deer Park, Texas, under two .research permits and one interim permit granted by
the U.S. Environmental Protection Agency (EPA). The wastes incinerated were
organochlorines--a mixture of trichloropropane, trichloroethane, and dichloro-
ethane—generated by Shell in the production of glycerine, vinyl chloride,
epichlorohydrin, and epoxy resins at its Deer Park, Texas, plant. Shell Chemical
Company incinerated a total of 16,800 MT (18,500 tons) of organochlorine waste
in four separate burns aboard the Dutch incinerator ship M/T Vulcanus in the
Gulf of Mexico during the period October 1974 to January 1975 (Wastler et al.,
1975; and Maritime Administration, 1975).
The research permits required that the stack emissions from the Vulcanus
be monitored.. Appropriate systems were installed to conduct the tests during
the first two burns. During each of the first two burns, 4,200 MT (4,600 tons)
of organochlorine wastes were burned in the two combustion chambers of the
Vulcanus at a maximum throughput of 25 MT (27.5 tons) per hour with a 1200°C
(2190°F) minimum and a 1350°C (2470°F) average flame temperature. The last
two burns were conducted under an interim permit issued by EPA, and the burns
were monitored by U.S. Coast Guard aerial serveillance.
Stack gas emissions were monitored during the first two burns to determine
plume dispersion characteristics and combustion efficiency. The findings indi-
cated that more than 99.970 of the organochlorine wastes were oxidized and that
the emissions consisted primarily of hydrogen chloride, carbon dioxide, and
water. The emissions were discharged directly into the atmosphere without scrub-
bing, and the marine monitoring surveys indicated that there were no measur-
able increases in concentrations of trace metals and organochlorides in the
water and marine life, that no adverse effects on migratory birds were ob-
served, and that the maximum hydrogen chloride concentrations were 3 ppm in
the air and 7 ppm at 6 m (19.7 ft) above sea level.
" As a result of these tests, EPA has granted Shell Chemical Company a 2.5-
year special permit to burn 50,000 MT (55,000 tons) of chemical waste by-products.
They burned 16,000 MT (17,600 tons) of organochlorine wastes in the period
February to March 1977 (Environmental Sciences and Technology, 1977).
39
-------
Although the wastes burned were not pesticides, the technology employed
may be transferable to the incineration of organochlorine pesticides marked
for disposal*
U.S. Air Force—Incineration of 8.7 million liters (2.3 million gallons)
of Herbicide Orange containing traces of the dioxin, TCDD, was accomplished
during August 1977 by the Vulcanus in mid-Pacific Ocean approximately 196 km
(120 miles) from Johnston Island and 1,600 km (1,000 miles) west of the
Hawaiian Islands. _The U.S. EPA permit issued to the U.S. Air Force and Ocean
Combustion Services, B.V., required at least 99.9% destruction efficiency.
Preliminary results of the incineration indicated a > 99.99% destruction effi-
ciency. No detectable TCDD was found in the incinerator stack samples. The cost
of the program was around U.S. $5 million (Kansas City Times, 1977; Chemical
and Engineering News, 1977b; Pesticide and Toxic Materials News, 1977).
Results
Pesticide incineration research and development has been conducted on a
laboratory and pilot scale and on a commercial/industrial scale by various
organizations. University, governmental, and government-funded research pub-
lished recently is reviewed in this report. Other research has been performed
by private firms to solve their own disposal problems or to provide disposal
services to others, but this is generally proprietary and unpublished and
cannot be reviewed. Table 1 shows those organizations whose research studies
are reviewed in this section, and some private firms who have performed in-
house reasearch.
The research and development review presented above includes most of the
research conducted on pesticide disposal by incineration. Some of this re-
search, however, provides only limited information since it fails to provide
the essential and complete data necessary for pesticide incineration opera-
tions. Foster D. Snell burned pesticides and pesticide containers in the open
with no pollution control, which is an unacceptable practice today. Chemagro
generated only limited data in its study, which never developed beyond the ex-
perimental stage. Incineration at sea conducted by Shell Chemical Company and
by the U.S. Air Force and Ocean Combustion Services, B.V., provided valuable
information on ocean incineration techniques and results; but the Shell Chemi-
cal Company tests did not incinerate pesticides, and data on the Air Force
tests are not available at present.
The studies conducted by MSU, UDRI, and MRI determined the temperatures
at which specific pesticides are completely combusted in laboratory apparatus.
In its study, MSU used differential thermal analyses, and UDRI and MRI used
both differential thermal analyses and thermal gravimetric analyses in their
studies. The results of these three studies are shown in Table 2.
40
-------
TABLE lo ORGANIZATIONS THAT HAVE CONDUCTED RESEARCH ON
PESTICIDE DISPOSAL BY INCINERATION
Laboratory and pilot-scale research
Canadian Government Defense Research Council) Suffield
Chemagro, Division of Mobay Chemical Corporation
Envirotech Systems, Inc.
Foster D« Snell, Inc0
MB Associates, Inc»
Marquardt Company
Midwest Research Institute
Mississippi State University
TRW Systems, Inc0
U»S» Army Land Warfare Laboratory, Aberdeen Proving Ground, Maryland
University of Dayton Research Institute
Versar, Inc o
Commercial industrial scale research
City of Palo Alto, California
General Electric Company
Midland-Ross Corporation
Shell Chemical Company
United States Air Force/EPA
Versar, Inc.
In°house research
Bartlett-Snow
Chem-Trol Pollution Services
Combustion Power Company
Dow Chemical Company
Monsanto Company
Rollins Environmental Services, Inc.
Velsicol Chemical Company
41
-------
TABLE 2. TEMPERATURES OF COMPLETE COMBUSTION OF PESTICIDES
DETERMINED IN LABORATORY EXPERIMENTS
Temperature of complete combustion
Pesticide
Aldrin
Recrystallized
19% granular
Atrazine
Reagent grade
Technical grade
80% wettable powder
80% wettable powder
Bromacil
Reagent grade
80% wettable powder
Captan
Technical grade
50% wettable powder
2,4-D (isooctyl ester)
Reagent grade
4 Ib/gal. formulation
DDT
Reagent grade
Reagent grade
Technical flakes
DNBP
Reagent grade
3 Ib/gal. formulation
DSMA
Reagent grade
3.2 Ib/gal. formulation
Dalapon
Reagent grade
85% wettable powder
°C
570
700
650
600
600
600
716
671
600
600
602
623
500
560
850
639
656
665
612
250
850
(continued)
42
(°F)
(1058)
(1292)
(1202)
(1112)
(1112)
(1112)
(1321)
(1240)
(1112)
(1112)
(1116)
(1153)
(932)
(1040)
(1560)
(1182)
(1213)
(1229)
(1135)
(482)
(1562)
Source—
*
MRI
MRI
MSU
MRI
MSU
MRI
MSU
MSU
MRI
MRI
MSU
MSU
UDRI
MSU
MSU
MSU
MSU
MSU
MSU
MSU
MSU
-------
TABLE 2. ((continued)
1
Temperature of complete combustion
Pesticide
Dicamba
Reagent grade
4 lb/gal. formulation
Dieldrin
Reagent grade
1.5 lb/gal • formulation
Oiuron
Reagent grade
80% we tt able powder
Kepone^
Reagent grade
Ma lath ion
Reagent grade
5 lb/gal. formulation
25% wettable powder
Mirex
Reagent grade
Technical grade
Nemagon^
Reagent grade
8.6 lb/gal. formulation
PMA
Reagent grade
95% water dispersible
Paraquat
Reagent grade
2 lb/gal. formulation
°C
840
850
620
640
775
550
500
663
715
650
700
850
800
596
545
646
613
592
(°F)
(1544)
(1562)
(1148)
(1148)
(1427)
(1022)
(932)
(1225)
(1319)
(1202)
(1292)
(1562)
(1472)
(1105)
(1013)
(1195)
(1135)
(1098)
Source^/
MSU
MSU
MSU
MSU
MSU
MSU
UDRI
MSU
MSU
MRI
UDRI
MRI
MSU
MSU
MSU
MSU
MSU
MSU
(continued)
43
-------
TABLE 2. (continued)
Temperature of complete combust ioi
Pesticide
Pic lor am (potassium salt)
Reagent grade
Recrystallized
11.6% solution
107, pellet formulation
Carbaryl
Reagent grade
10% dust
2,4,5-T (acid)
Reagent grade
4 Ib/gal. formulation
Toxaphene
Technical grade
20% dust
Trifluralin
Reagent grade
4 Ib/gal. formulation
Vernolate
Reagent grade
6 Ib/gal. formulation
Zineb
Reagent grade
Technical grade (85%)
75% wettable powder
757o wettable powder
°C
550
900
640
400
724
678
717
731
aooi/
710
879
842
447
508
840
800£/
690
800
(°F)
(1Q22)
(1652)
(1184)
(752)
(1335)
(1252)
(1323)
(1348)
(572)
(1310)
(1614)
(1548)
(837)
(946)
(1544)
(1472)
(1274)
(1472)
n
Source^'
MSU
MRI
MSU
MRI
MSU
MSU
MSU
MSU
MRI
MRI
MSU
MSU
MSU
MSU
MSU
MRI
MSU
MRI
a/ Mississippi State University (MSU) data from Kennedy et al. (1969),,
University of Dayton Research Institute (UDRI) data from Duvall and
Rubey (1976).
Midwest Research Institute (MRI) data from Ferguson et al. (1975)0
b/ Weight loss of toxaphene sample was 95% at 300°C (572°F)<=
£/ Weight loss of zineb sample was 80% at 800°C (1472°F)<>
44
-------
Those studies conducted by MRI; Versar, Inc.; Envirotech, Inc.; the U.S.
Army Land Warfare Laboratory; the Marquardt Company; TRW Systems Group; and
the Canadian Government Defense Research Establishment, Suffield, were pilot-
scale tests performed in model and prototype incinerators constructed for the
destruction of pesticides. Studies by GE; Midland-Ross Corporation; Versar,
Inc.; and the City of Palo Alto, California, were performed in commercial-scale
incinerators. All these studies provide valuable information and the essential
data base which exists today in pesticifle incineration research. Table 3 gives
the operating parameters of incineration research tests performed by these
organizations.
Data provided in Table 3 include the feed rate, excess air, average tem-
perature, retention time, and destruction efficiency for each individual pesti-
cide formulation tested by these organizations. Since many of the studies were
extensive, only representative data for each test are shown. These data were
chosen to show the relationship between the combustion temperature, percent
excess air, and retention time for highly efficient pesticide destruction
(* 99.99%).
i
Data in Table 3 show the following general trends:
1. The retention time necessary for complete destruction decreases with
increasing temperature at a constant excess air input.
2. Temperatures required for the "complete" destruction of most pesticides
shown are below 1000°C (1832°F) provided the proper excess air and retention
time are used. For some pesticides the complete destruction temperatures are
wide in range and are quite low if enough retention time is allowed.
3» All of the tests (except for MRl's 0.3% mirex bait test) were able to
achieve a destruction efficiency of 99.99% or greater. Though the number of
pesticides studied is only a small fraction of the total number of pesticides
on today's market, the tests indicate that incineration has a great potential
for the efficient and complete destruction of pesticides.
POTENTIAL IMPACTS
The potential environmental and economic impacts of pesticide disposal
by incineration are discussed below.
Potential Environmental Impacts
The discussion which follows concerns the environmental impact of toxic
stack gas emissions and waste pesticide emissions from any incineration facil-
ity. First, the toxic products of pesticide incineration are discussed in
general terms to provide insight into the nature of the problem of stack gas
emissions, pollution control device collections, and ash residues.
45
-------
TABLE 3. OPERATING PARAMETERS OF INCINERATION RESEARCH TESTS OF INDIVIDUAL PESTICIDES
Pe st ic Ide
Aldrln
Atrazlne
Captan
Chlordanc
Chlordane/
Dleldrln
2,4-D
(Ester)
2,4-D/
2,4,5-T
(Ester)
1:1 mixture
Pesticide
formulation3-'
Z by weight
41.2 (EC)
41.2 (EC)
41.2 (EC)
41.2 (EC)
19 (G)
19 (C)
19 (G)
40.8 (FC)
40.8 (FC)
40.8 (FC)
80 (WP)
80 (WP)
50 (WP)
50 (WP)
50 (WP)
5 (D)
5 (l»
72 (EC)
72 (EC)
72 (EC)
18/11 (EC)
18/11 (EC)
18/11 (EC)
Not stated
Not stated
Not stated
Not stated
Not stated
Not stated
Formulation
feed rate
t/hr (gal/hr)
2.69
3.63
7.65
2.95
9.84
9.98
19.50
16.2
6.55
15.9
3.4
3.6
6.17
3.54
6.44
0.45
0.45
0.72
0.72
0.95
2.8
3.8
3.8
3.8
3.8
3.8
0.95
0.95
0.95
(0.71)
(0.96)
(2.02)
(0.78)
(21.7)£/
(22.0)c/
(43.0)£/
(4.28)
(1.73)
(4.20)
(7.5)c/
(B.O)c/
(13.6)c/
(7.8)c/
(14.2)c/
(l.O)c/
(l.O)c/
(0.19)
(0.19)
(0.25)
(0.75)
(1.0)
(1.0)
(1.0)
(1.0)
(1.0)
(0.25)
(0.25)
(0.25)
Excess
air
380
203
128
70
113
48
118
143
52
140
146
43
99
192
137
71
6
48
98
12
7
46
47
-3
46
13
-8
-8
15
Avc rage
temperature
°C (CF)
600
830
1020
1140
860
1150
1100
700
1040
940
940
1050
690
660
1000
950
1120
920
840
1150
920
950
940
86O
880
910
420
900
1100
(1120)
(1530)
(1870)
(2080)
( 1580)
(2100)
(2020)
( 1300)
(1900)
(1720)
(1720)
(1920)
( 1280)
(1220)
(1830)
(1745)
(2050)
( 1690)
(1540)
(2105)
(1695)
(1750)
(1725)
(1575)
(1615)
(1675)
( 780)
(1650)
(2010)
Retention
time
14.5
8.9
3.5
4.4
6.2
5.2
2.8
6.9
5.5
2.9
10.8
5.5
13.5
8.1
3.6
0.13
0.51
0.63
0.52
0.18
0.94
0.48
0.17
0.90
0.60
0.25
3.3
0.70
0.17
Destruction
'efficiency Type of
(7.) incinerator
>
5.
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
Pilot-scale multiple
chamber
Pilot-scale multiple
chamber
Pilot-scale multiple
chamber
Pilot-scale liquid
inject Ion
Pilot-scale liquid
injection
Pi lot- scale liquid
injection
Pilot-scale liquid
Injection
Organization
performing
the test
Midwest Research
Institute
Midwest Research
Institute
Midwest Research
Institute
. TRW Systems Group
TRW Systems Group
TRW Systems Group
TRW Systems Group
(continued)
-------
TABLE 3» (continued)
Pesticide
nor
Dleldrln
Herbicide
Orange
Kcpone®
Pesticide
formulationa/
T. by weight
20
20
20
20
5
5
5
5
5
20
20
20
25
•25
25
10
10
10
20
20
75
75
75
75
10
10
25
25
20
15
15
15
(OS)
(OS)
(OS)
(OS)
(K)
(OS)
(OS)
(OS)
(OS)
(OS)
(OS)
(OS)
(EC)
(EC)
(EC)
(0)
(D)
(D)
(K)
(K)
(0)
(D)
(D)
(0)
(D)
(D)
(EC)
(EC)
(K)
(EC)
(EC)
(EC)
(EC)
(EC)
(EC)
UnknounS/
Formulation
feed rate
f/hr (gal/hr)
113
| n-j
1O<
113
182
- 205
3.0
1.9
3.8
1.9
0.95
0.72
0.95
1.9
3.8
1.9
0.45
0.45
0.45
0.91
2.25
1.18
3.0
0.91
2.25
0.98
2.23
1.91
4.63
18.9
3.8
3.8
2.8
195
260
260
(30)
i tin \
(4H J
(30)
(48)
(- 53)
(0.75)
(0.5)
(1.0)
(0.5)
(0.25)
(0.19)
(0.25)
(0.5)
(1.0)
(0.5)
(l.O)c/
(l.O)c/
(l.O)c/
(2.0)d/
(5.0)d/
(2.6)d/
(6.6)d/
(2.0)d/
(5.0)d/
(2.l6)c/
(4. 9 l)c/
(4.23)c/
(10.25)c/
(5.0)
(1.0)
(1.0)
(0.75)
(430)c/
(570)c/
(570)c/
Unknown*/
Excess
air
(*>
157
If."*
LD J
123
122
No data
30
30
50
76
26
70
92
30
65
103
30
47
76
> 100
>. 100
> 100
> 100
> 100
> 100
164
156
162
143
No data
-7
46
91
37
52
53
No data
Average
temperature
°C <°F)
870
Q 7f]
O /U
980
980
900
1090
1200
1000
860
1040
940
320
890
1040
820
1130
1010
930
840
840
760
790
630
630
930
1020
940
930
1400
870
970
910
1220
1040
980
1090
( 1600)
I \(\(\f\\
\ LOUU/
( 1800)
( 1800)
(1650)
(2000)
(2200)
(1830)
(1580)
(1990)
(1720)
(600)
( 1640)
( 1900)
(1510)
(2060)
(1850)
(1705)
(1550)
(1540)
(1410)
( 1460)
(1170)
(U70)
(1710)
( 1860)
(1730)
(1700)
(2550)
(1600)
(1785)
(1665)
(2210)
( 1900)
(1790)
(2000)
Retention
time
(seclfe/
3.4
2.9
3.0
4.0
No data
0.7
0.5
0.2
0.9
0.5
0.2
0.2
1.2
0.14
0.3
0.14
0.14
O.I)
45 mln
45 mln
45 mln
45 mln
~45 mln
-45 mln
2.6
3.2
2.5
1.8
3.0
0.72
0.47
0.18
0.18
0.16
0.14
2.0
De struct ion
efficiency Type of
(%) Incinerator
99.99
99.99
99.99
99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.98
> 99.99
> 99.99
> 99.98
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
99.98
99.98
> 99.99
•> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
=• 99.99
> 99.99
> 99.99
Commercial liquid Injection
Pilot-scale liquid injection
Pilot-scale liquid Injection
Pilot-scale multiple hearth
Municipal multiple hearth
sewage sludge
Pilot-scale multiple chamber
Prototype pilot-scale liquid
Injection
Pilot-scale liquid Injection
fB*
Pilot-scale SUE''btirner
Commercial high-temperature
sludge incinerator
Organ! Ear-ion
performing
the test.
General Electric
Canadian Defense Re-
search Establishment
TRW Systems Croup
Versar, Inc., and
Envirotech, Inc.
Versar, Inc. and City of
Palo Alto, California
Midwest Research
Institute
U.S. Army Land Warfare
Laboratory
TRW Systems Group
• Harquardt Corporation
Midland-Ross Corporation
Surface Division
(continued)
-------
TABLE 3. (continued)
CD
Pe at ic tde
Ltndane
Ma lath ion
Hlrex
Pic lo ram
2,4,5-T
Pr st Ic ide
formulation?'
% by weight
1
1
1
12
12
12
57
57
57
25.
25
25
0.3
0.3
0.3
0.3
21.5
21.5
21.5
10
10
10
20
20
20
20
Ester
Kstei
Ester
(U)
(0)
(D).
(EC)
(EC)
(EC)
(EC)
(EC)
(EC)
(WP)
(WP)
(WP)
(B)
(B)
(B)
(B)
(WB)
(WB)
(WB)
(P)
(P)
(P)
(PS)
(PS)
(PS)
(PS)
Formulat Ion
feed rate
f/hr (g.il/hr)
0.7 (1.5)c/
0.7 (l.5)c/
0.45 (l.O)c/
2.8 (0.757
3.8 (1.0)
2.8 (0.75)
2.38 (0.63)
6.47 (1.78)
3.60 (0.95)
13.2 (29)c/
19.2 (42)c/
13.8 (31)c/
10.9 <24)c/
10.5 (23)£/
10.9 (24)c/
24.0 (53)c/
8.8 (2.3)
5.7 (1.5)
13.6 (3.6)
16.8 (37)c/
32.2 (7l)c/
17.3 (38)c/
0.90 (2.0)d/
2.25 (5.0)d/
0.55 (1.2)d/
1.73 (3.8)d/
3.8 (1.0)
3.8 (1.0)
3.8 (1.0)
Exco.ss
air
W
19
89
67
2
32
31
176
95
130
113
37
156
79
225
141
57
298
62
116
226
72
93
> 100
> 100
> 100
> 100
-11
49
33
Ave rage
temperature
CC (°F)
1040 (1900)
810 (1490)
950 (1740)
960 (1760)
1080 (1975)
1270 (2310)
620 (1140)
960 (1760)
1050 (1930)
730 (1340)
1040 (1900)
930 (1710)
700 (1290)
590 (1090)
920 (1690)
900 (1650)
530 (990)
930 (1700)
1030 (1880)
640 (1190)
930 (1700)
1020 (1870)
780 (1430)
780 (1430)
700 (1290)
700 (1290)
920 (1680)
840 (1540)
880 (1615)
Re tp lit Ion
time
(secjfr'
0.50
0.38
0.13
0.86
0.48
0.14
13,3
7.8
4.4
11.3
7.7
3.7
12.2
6.2
3.3
5.8
15.6
7.9
2.4
14.3
9.5
2-7
-45 mln
-45 mln
-45 mln
-45 mln
0.93
0.65
0.23
Destruction Organization
efficiency Type of performing
(X) Incinerator the test
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
•> 99.99
> 99.99
> 99.99
•> 99.99
> 99.99
? 99.70
> 98.21
> 99.97
> 99.98
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
f 99.99
> 99.99
> 99.99
> 99.99
> 99.99
> 99.99
Pilot-scale liquid Injection TRW Systems Group
Pilot-scale multiple chamber Midwest Research
institute
Pilot-scale multiple chamber Midwest Research
institute
Pilot-scale multiple chamber Midwest Research
Institute
Pilot-scale multiple hearth Vcrsar, Inc. and
Envlrotech, Inc.
Municipal multiple hearth Versar, Inc. and
sewage sludge C^ty of Palo Alto,
California
Pilot-scale liquid Injection TRW Systems Croup
(continued)
-------
TABLE 3. (continued)
Pesticide
formulation?'
Pesticide
To xaphe ne
Zlneb
%by
60
60
60
20
20
20
75
75
75
we Ight
(EC)
(EC)
(EC)
(D)
(0)
(D)
(WP)
(WP)
(WP)
Formulation
feed rate
l/hr
2.0
2.8
2.35
15.0
16.4
14.5
4.3
2.3
2.3
(gal/hr)
(0.53)
(0.75)
(0.62)
(33)c/
(36)c/
(32)c/
(9.5)c/
(5. l)c/
(5. l)c/
Excess
air
tt)
150
47
124
94
166
121
102
165
151
Ave rage
temperature
CC
650
1040
980
670
670
1010
680
650
(CF>
(1200)
( 1900)
( 1800)
(1240)
(1240)
( 1850)
( 1260)
(1200)
940((1730)
Retention
ttmc
(sec^'
13.2
6.9
4.8
16.0
11.0
5.2
10.3
8.6
3.5
Destruction Organization
ef f Ic lency
>
>
>
>
>
>
>
>
>
a)
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
99.99
Type of performing
incinerator the test
Pilot-scale multiple chamber Midwest Research
Institute
Pilot-scale multiple chamber Midwest Research
Institute
a/ B = bait; D = dust; EC = emulsiflable concentrate; FC = flowable concentrate; G ~ granular; K = in kerosene; OS = oil solution; P — pellets;
~ PS = polyalcohol solution; WB = water base liquid; and WP = wett.ible powder.
b/ Retention time for MRI data are the sum of the primary and secondary chamber retention times.
£/ Quantities given In kilograms per hour (pounds per hour).
d/ Pesticide mixed with sludge fed to Incinerator at rate of 45 kg/hr (100 Ib/hr).
e/ Kepone®(4 kg maximum sample slie) was mixed with sewage sludge fed to incinerator.
-------
Then, the impacts of toxic stack gas emissions and waste pesticides transported
from the facility prior to incineration are discussed for air quality, water
quality, and soil quality.
Toxic Products of Pesticide Incineration—
Pesticides represent a wide variety of chemical substances formulated into
numerous products in different physical states. Incineration of a diversity of
waste pesticides can be expected to generate gaseous products, particulates,
and ash residues of many types. Gases (e.g., carbon monoxide, nitrogen oxides,
sulfur dioxide, elemental halogens, hydrogen halides, smoke, and particulates)
as well as ash residues containing alkali, alkaline earths, and heavy metal
salts and oxides may be produced in an efficient pesticide incineration opera-
tion. When the incinerator is inadequately designed or operated? or malfunc-
tions, other toxic inorganic gases such as hydrogen sulfide, ammonia; and
hydrogen cyanide and unburned volatile pesticides and products of incomplete
combustion or pyrolysis may be produced.
Both laboratory- and pilot-scale incinerations of organic pesticides under
optimum operating conditions have produced hydrogen chloride, nitrogen oxides,
phosphorus pentoxide, and sulfur dioxide from combustion of chlorine**,
nitrogen-, phosphorus-, and sulfur-containing compounds. Sulfur dioxide was
found in most emissions because of the sulfur in the auxiliary petroleum fuel
often used or in formulation adjuvants. Nitric oxide is a product common to
high temperature combustions above IIOO^C (2012°F)« Hydrogen cyanide can be
formed when incinerating nitrogen-containing pesticides, and methane? other
hydrocarbons, and carbon monoxide are sometimes found in the gaseous product.
Particulates are often emitted in large amounts when solid formations are in~
cinerated.
Inorganic pesticides, such as ammonium sulfamate, elemental sulfur» and
ammonium thiocyanate, may be components of combustible pesticide mixtures to
be incinerated or, in some cases, may be incinerated directly to dispose of
them. The resultant flue gas and ash constituents of burning these pesticides
could result in sulfur dioxide and other hazardous substancess depending upon
the pesticide being incinerated and the operating conditionso
The uncontrolled release of the above chemical substances into the environ-
ment poses a serious threat to the quality of the air, water, soil, and animal
and plant life.
Air Quality—
Pesticide incineration operations can adversely affect air quality in two
wayss by stack gas emission and from waste pesticide dusts and vapors being
transported by the wind during unloading and handling operations prior to in-
cineration. By far the more serious impact comes from stack gas emissions con-
taining toxic gases, vaporss mists, and particulates. Volatilizations sublima=>
tion, or wind transport of the pesticides prior to incineration are lesser
impacts which may also result.
50
-------
Pesticide incineration operations emit large volumes of stack gases into
the air and have the potential for serious environmental damage if the emis-
sions are not properly controlled. Many of the toxic substances mentioned above
would be emitted in excessive amounts and would contaminate the air. Emissions
would be more severe during periods of operational malfunctioning^when unburned
pesticides and partial combustion products are emitted and during periods of
adverse meteorological conditions such as thermal inversions and low wind speeds*
Incinerators which are improperly designed, which operate with Inadequate pol-
lution control devices, or which are used for the wrong types or excessive
quantities of pesticides would also create adverse impacts on air quality.
Impacts of polluted stack emissions on air quality would probably be short-
term if the cause were operational abnormalities of infrequent and short dura-
tion. Long-term impacts would result if gross emissions of prolonged and
frequent periods of pollution were created by improperly designed and.controlled
incinerators. The consequences of both short- and long-term impacts would depend
upon the chemical nature of the pollutant and the assimilative and dissipative
capacities of the air environment.
These impacts can be largely mitigated by the use of efficient pollution
controls for the known kinds of waste pesticides to be incinerated; by moni-
toring devices that detect and warn of excessive pollutant emissions indicating
performance irregularities; and by strict observance of acceptable operating
procedures which restrict the types and quantities of pesticides incinerated
only to those for which the incinerator was designed, insuring that combus-
tion efficiencies and stack gas compositions are maintained at specified levels
of acceptability.
Water Quality-
Pesticide incineration operations can impact surface waters through con-
tamination by stack gas emissions and by pesticide wastes transported by wind
or storm water runoff from the facility unloading and handling areas. By far
the most significant adverse impact can come from stack gas emissions contain-
ing gases, vapors, mists, and particulates which can settle on or be absorbed
into nearby surface waters. Lesser impacts caused by waste pesticides being
transported from the facility by wind or runoff may also result.
Water quality impacts of stack gas emissions would be more severe during
periods of operational malfunctioning when unburned pesticides and partial
combustion products are emitted and during periods of adverse meteorological
conditions such as thermal inversions and rainfall. Incinerators which are
not properly designed or which operate with inadequate pollution control devices
to treat the stack emissions would also create adverse impacts on the surface
waters. The adsorption of toxic substances from the stack gases which contact
surface waters and the settling of particulates on surface waters would con-
itaminate the water and might impair its usefulness for agriculture, for domes-
tic and recreational purposes, and for aquatic life habitats.
51
-------
In addition to surface water contamination by stack gases, the surface
and groundwaters could be contaminated by storm water runoff containing pes-
ticides from ground spills, leaking containers, and by vapors and dusts trans-
ported by wind from the facility to nearby surface waters.
Impacts of polluted stack emissions and contaminated storm runoff on
water quality would probably be short-term if the causes were operational mal-
functions of short and infrequent duration of the incinerator, or brief storm
runoff episodes. Long-term -impacts- would result if -gross--emi-ssl-ons of prolonged
and frequent periods of pollution were created by improperly designed and con-
trolled incinerators or if excessive spills and improper handling of waste
pesticides resulted in the continuous exposure of the surrounding surface and
groundwaters to contaminated storm water runoff. The consequences of both short-
term and long-term impacts would depend upon the chemical nature of the pol-
lutants and the assimilative and dissipative capacities of the surrounding
waters.
Soil Quality—
Soil areas around an incinerator facility would be exposed to the same
pollutants and in the same manner as would the surface waters, that is, con-
tamination by stack gas emissions and waste pesticides transported by wind
and storm runoff. Mitigation of these impacts would be achieved by the same
countermeasures suggested in the preceding sections on air and water quality.
The nature of these impacts, both short-term and long-term, merits further
description.
Soil quality would be adversely affected primarily through the loss of
vegetative cover. Many plants exposed to phytotoxic pesticides in stack gas
emissions at significant levels during incinerator malfunction would be de-
stroyed. Of even greater concern would be the low level exposure of plants to
inorganic combustion gases and particulates not completely scrubbed from stack
gases under normal operating conditions. Many plants are sensitive and can
be acutely injured by exposures to low concentrations of sulfur dioxide,
nitrogen dioxide, fluorides, chlorides, aliphatic hydrocarbons, and other com-
pounds commonly found in stack gases of pesticide incinerators. Herbicides
transported by wind and storm runoff would also destroy vegetative cover.
Destruction of vegetative cover would lead to drastic reductions or
changes in soil organism populations essential to soil quality and productive
capacity through loss of habitat and food supply. Uncovered soil would be ex-
posed to the direct effects and action of the sun, wind, and rains and would
be subject to accelerated loss of moisture, leaching of essential elements,
and erosion, with the loss of productive top soil and alteration of drainfield
capacity and patterns.
These impacts would be essentially short-term, possibly a growing season,
if pollution incidents were infrequent or not repeated. However, the potential
52
-------
for long-term soil impacts, which may be irreversible, would be great in the
case of prolonged exposure to low-level pollutants*
Potential Economic Impacts
The capital and operating costs of pesticide incineration facilities can
only be estimated since there are many variables involved. Capital costs will
vary widely from one facility to another since they are dependent upon variables
such as installation, land, feed capacity, materials of construction, feed sys-
tems, pollution control systems, etc* The feed system costs can be substantial
if several physical forms (liquids, solids, sludges) are processed in a single
incinerator. The required pollution control system will depend upon the types
of pesticides to be incinerated, the resultant gaseous emissions, and the regu-
lated emission limits. The cost of the system will increase substantially as
the degree of complexity and sophistication increases*
Operating costs will also vary widely for different facilities since cost
variables such as labor rates, utility and energy usage, equipment lifetimes,
down-time, ash disposal, scrubber water treatment and disposal, and plant over-
head are involved. Each of these costs (except labor rates) is dependent to
a large degree upon not only the type of incineration facility but the types,
physical 'forms, and quantities of pesticides to be incinerated.
Scurlock et al* (1975) reported the capital and operating costs for
hazardous waste incineration for various types of incinerators. Capital costs
ranged from $2,000 to $20,000 per daily ton of capacity, and operating costs
ranged from $3 to $55 per ton of waste incinerated. The capital costs, how-
ever, were generally for the installed incinerator and did not include such
items as pollution control equipment, land, feed systems, and other facility
costs* The operating costs were not specific as to what cost items were in-
cluded in the estimates. Dollar figures were not specified as to year, and the
ranges used were wide. Still, these estimates indicate that incineration costs
are high, particularly if the high side of the cost range is used to allow for
costs not included in the estimates.
Since incineration costs depend on many variables whose values are inde-
terrainant for pesticide disposal operations, it is impossible to estimate costs
that have any meaning until more is known about the facilities that will be
required to incinerate pesticides. The estimates made by Scurlock et al. (1975)
give some indication as to the magnitude of the costs.
The EPA is currently evaluating the economic impacts of the implementation
of regulations promulgated under Subtitle C of the Resource Conservation and
Recovery Act of 1976 (EPA, 1978). These regulations will deal with the disposal
pf hazardous waste materials* As part of this assessment, a series of economic
53
-------
analyses are being conducted. The results of this study will provide much of
the needed data on the economic costs of incineration as well as other methods
of disposal.
FUTURE RESEARCH NEEDS
A review of the past and current pesticide incineration research and de-
velopment presented previously and Tables 2 and 3 suggest that the information
and data base for pesticide incineration is quite limited for a group of com-
pounds that includes about 550 different pesticide Al's and about 24,000 dif-
ferent formulations; for a technology which offers a wide variety of incinera-
tion devices; and for a technology offering a wide variety of emission-control
devices. Few data have been generated for various chemical classes of pesti-
cides, for several types of commercial-scale incinerators, or for readily avail-
able pollution control devices.
These technology gaps can only be bridged in the future by conducting more
research in specific areas. The questions listed below highlight areas where
data are incomplete or absent from the present body of knowledge of pesticide
incineration operations.
* Which pesticides and their formulations can be safely incinerated,
and which cannot? How can heavy metals be removed from certain pesti-
cides prior to incineration? Can pesticide containers be safely in-
cinerated?
* What are the necessary operating conditions for commercial-scale
incinerators to destroy pesticides effectively and efficiently? How
do these operating conditions vary for different pesticides and dif-
ferent formulations? Which types of incinerators offer the most advan-
tages for pesticide disposal? How much will these methods cost?
* What toxic substances are generated by the incineration of specific
pesticides and specific formulations? Are they gases, vapors, mists,
or particulates? Are they found in the flue gases or ash? What quanti-
ties are present? How toxic are they to man and his environment?
* What existing pollution-control devices are effective in removing
specific pollutants from flue gas streams? Which devices should be
used for which pollutants? Should scrubber water be acid,, alkaline,
or neutral? What characteristics, such as size, capacity, materials
of construction, etc., should these devices have for different pesti-
cides? What will these devices cost in relation to the effectiveness
they achieve?
54
-------
* Should regulations and guidelines on emission limits from pesticide
incinerators be federal or local? Should standards be set for all
pesticides and all pollutants, or just for those that are the most
toxic to man and his environment? What are the economic trade-offs
between very stringent standards and less stringent standards? Can
suggested standards be met with present .technology, or will further
research and development be required in incineration and pollution
control technology?
Future research and development should be directed toward answering these
questions and should be conducted by augmenting past and current research, and
by conducting studies in areas which have received little or no attention to
dateo Needed activities include:
(1) Expand the data base on pesticide incineration; Too much of the past
research has been concerned with the incineration of chlorinated hydrocarbons,
particularily DDT and Herbicide Orange. Few studies which examine the other
chemical classes of pesticides have been conducted. The MSU study and the MRI
study examined various classes of pesticides but only on a laboratory- and
pilot-scale level.
Future research is needed to broaden the data base on pesticide inciner-
ation characteristics for more classes of compounds, such as anilides, ureas,
uracilsj nitrated hydrocarbons, organophosphates, triazines, and carbamates,
and at the same time, to examine representative pesticides within these classes,
since most of the classes contain a wide diversity of individual compounds.
(2) Conduct more commercial-scale incineration studies; This review of
past and current research reveals that little pesticide incineration research
has been conducted in commercial readily available and commonly used incin-
eratorss Little is known about pesticide destruction efficiencies, incinerator
operating parameters, etc., for commercial-scale incinerators, with the excep-
tion of DDT. Unless future research is conducted in commercial facilities,
the circumstances of full-scale incineration operations will only be extrapo-
lations of pilot-scale studies. Generalized operating guidelines for pesticide
incineration, such as those developed in the MRI study (Ferguson, 1975), must
be verified (or revised) by additional full-scale testing.
(3) Determine specific products of pesticide incineration; Research aimed
at expanding the data base and utilizing commercial incinerators must determine
not only the efficient operating conditions of the incinerator but the specific
products created under various conditions and for various pesticides. The dis-
cussion in Section 4 of this report on the toxic substances which may be produced
from incinerating various pesticides and formulations .shows that a wide variety
of toxic substances may be created and become a part of the stack gases, pollu-
;tion control collections, or ash residues.
55
-------
Until the types, quantities, physical states, and properties of toxic
products of pesticide incineration are determined for the various chemical
classes and formulations, little can be done to assess the significance of
environmental pollution, to design and operate appropriate pollution control
devicesj or to establish regulations and guidelines for ambient air limits
for pesticide incineration operations*
(4) Test pollution control devices for control of specific pollutants;
Most studies conducted to date have generated few data on the ability of spe-
cific types of pollution control devices to control specific toxic pollutants.
The ability of pollution control devices to control a wide range of gas,
vapor* mist, and particulate emissions in both pilot-scale and commercial
facilities must be determined*
(5) Determine the capital and operating costs of pesticide incineration;
After more research and development has been performed on pesticide incineration
technology and after incineration facilities have been defined in more detail
as to their construction and operation, it will be necessary to estimate and
determine the capital and operating costs of pesticide incineration. These
estimates should include cost comparisons between alternate pollution control
systems to determine the environmental and economic trade-offs of pesticide
incineration techniques.
56
-------
REFERENCES
Babbitt, R. The Marquardt Company» Personal communication to G. Kelso. May 5,
1978.
Games, R0 A», EPA/MERLj Cincinnati, OhiOo Personal communication to
R. Wilkinson, Sept, 14, 1977.
Chemical and Engineering News, po 20, Maro 14, 1977a.
Chemical and Engineering News, p» 20, Sept* 12, I977b.
Chemical Engineering, p0 61, Mare 28, 1977.
Duvall, D« S., and Wo Ao Rubeyo Laboratory Evaluation of High Temperature De-
struction of Kepone®and Related Pesticides. Tech. Rep. UDRI-TR-76-21. Uni-
versity of Dayton Research Institute. EPA-600/2-76-299, May 1976.
Environmental Protection Agencyo Regulations for Acceptance and Recommended
Procedures for Disposal and Storage. Federal Register, 39(85):Part IV, May 1,
1974o
Environmental Protection Agencyo Preliminary Working Draft: Environmental
Impact Statement for Subtitle C, Resource Conservation and Recovery Act of
1976 (RCRA). Volume 1, Febo 7, 1978.
Environmental Sciences and Technology, ll(3):236-237, 1977.
Ferguson, To Lo, F» Jo Bergman, Go R. Cooper, R. T. Li, and F. I. Honea. Deter-
mination of Incinerator Operating Conditions Necessary for Safe Disposal of
Pesticides. EPA-600/2-75-041, Deco 1975.
Holloman.Mo E., B. Ro Layton, Mo V. Kennedy, and C. R. Swanson. Identification
of the Major Thermal Degradation Products of the Insecticide Mirex. J. Agr.
Food Chem., 23(5):1011-1012, 1975„
Holloman, M« Ee, FoYo Hutto, Mo Vo Kennedy, and C. R. Swanson. Thermal Degrada-
tion of Selected Chlorinated Herbicides. J. Agr. Food Chem., 24(6):1194-1198,
1976.
Kansas City Times, p0 13A, Septo 8, 1977.
57
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Kelso, G. L., R. R. Wilkinson, T. L. Ferguson, and J* D. Maloney, Jr. De=
velopment of Information on Pesticides Manufacturing for Source Assessment.
EPA Contract No. 68-02-1324, Task 43, July 30, 1976.
Kennedy, M. V., B. J. Stojanovic, and F« L. Shuraan, Jr. Chemical and Thermal
Methods for Disposal of Pesticides. Res. Rev., 29:89, 1969.
Kennedy, M. V., B. J. Stojanovic, and F. L. Shuraan, Jr. Chemical and Thermal
Aspects of Pesticide Disposal. J. Environ. Quality, I(l)r63, Jan.-Mar.
1972a.
Kennedy, M. V., B. J. Stojanovic, and F. L. Shuman, Jr. Analysis of Decom-
position Products of Pesticides. J. Agr. Food Chem., 20(2):341, 1972b.
Lee, G. K., F. D. Freidrich, B. C. Post, and H. Whaley. The Thermal Destruc-
tion of DDT-Bearing Powders. Canadian Combustion Research Laboratory, Room
234, Jan. 1971.
Leighton, I. W«, and J. B. Feldman. Demonstration Test Burn of DDT in General
Electric*s Liquid Injection Incinerator. U.S. Environmental Protection Agency,
1975.
Maritime Administration. Chemical Waste Incinerator Ship Project. U.S. Depart-
ment of Commerce, NTIS PB-246 727, 1975.
Montgomery, W. L., B. G. Cameron, and W. S. Weaver. The Thermal Destructor.
Defense Research Establishment Suffield, R270, Oct. 1971.
Munnecke, D., H. R. Day, and H. W. Trask* Review of Pesticide Disposal Research^
Rep. No. SW-527. U.S. Environmental Protection Agency, 1976.
Ottinger, R. S., J. L. Blumenthal, D. F. Dal Porto, G« I. Gruber, M. J. Santy,
and C. C. Shih. Recommended Methods of Reduction, Neutralization, Recovery,
or Disposal of Hazardous Waste. NTIS PB-224 582, Volume 3, Aug° 1973o
Pesticide and Toxic Materials News. p. 33, Aug. 10, 1977.
Putnam, R. C., F. Ellison, R. Protzmann, and J. Hilovsky. Organic Pesticides
and Pesticide Containers. Rep. No. EPA-SW-21C-71, Foster D. Snell, Inc.,
Florham Park, New Jersey, 1971.
Rosen, H. H. Pesticide Pyrolysis Device. Tech. Rep. No. 74-89.'U.S. Army
Land Warfare Laboratory, Aberdeen Proving Ground, Maryland, 1974.
Riley, B. T. Summation of Conditions and Investigations for the Complete Com-
bustion of Organic Pesticides. U.S. Environmental Protection Agency Municipal
Environmental Research Laboratory, EPA-600/2-75-044, Oct., 1975.
58
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Scotts. Ro Co,.Vice President of Administrations Chemagro Agricultural Division,
Mobay Chemical Corporation* Personal communication to R. Wilkinson, Oct. 21,
1977.
Scurlock, At. Co, A* W. Lindsey, T. Fields, Jr., and D« R. Huber. Incineration
in Hazardous Waste Management« U.Sc Environmental Protection Agency, NTIS
PB-261 049, 1975.
Shihs G» C., R« Fo Tobias, Jo Fo Clausen, and R. J. Johnson. Thermal Degradation
of Military Standard Pesticide Formulations. TRW Systems Group, Redondo Beach,
California, Mar» 1975,
Stojanovic, Bo Jo, Mo Vo Kennedy, and F. Lo Shuman, Jr. Development of Incinera-
tion Technology for Disposal of Pesticide Wastes and Containers. Mississippi
Agricultural and Forestry Experiment Station, USDA Grant No. 12-14-100-9937(34),
June 1972a (unpublished information).
Stojanovic, B. J»» F« Hutto, Mo Vo Kennedy, and F. L. Shuman, Jr. Mild Thermal
Degradation of Pesticides Jo Environo Qualityo 1(4):397, 1972b.
Tenzerj, R. E., Program Manager, MB Associates, Inc. Personal communication to
R. Wilkinson, Febe 17S 1978o
U.So Patent No. 3,70193550 Chemagro Agricultural Division, Mobay Chemical Com-
pany, Filed Nov. 24, 1971o
Wastler, T. A«, C. K. Offutt, Co Ko FitzSimmons, and P. E. Des Rosiers. Disposal
of Organochlorine Wastes by Incineration at Sea. NTIS PB-253 979, July 1975.
Whitmore, Fo C. A Study of Pesticide Disposal in a Sewage Sludge Incinerator.
EPA/530/SW-116c, Versar, Incos Springfield, Virginia, 1975.
59
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SECTION 5
BIOLOGICAL METHODS
INTRODUCTION
Biological methods offer an interesting approach to pesticide disposal.
Biological treatment of municipal and industrial waste, is common, but very
little information on the applicability of this methodology to the elimina-
tion of unwanted pesticides is available. The potential for such applications
is discussed in this section.
Biological disposal methods may be employed to reduce or eliminate any
"biodegradable" pesticide waste. The refuse must normally be an organic com-
pound so that it may serve as a carbon source for microorganisms. But this
statement is not absolute since inorganic compounds containing valuable
nutrients—notably nitrogen compounds--may also be attacked through biologi-
cal processes. Obviously, the microorganisms involved must be able to tolerate
the toxic properties of the unwanted pesticide or hazardous material, at least
at dilute concentrations!,
Conditions necessary for degradation vary according to the nature of the
disposal system and the active organisms. Neither pH nor temperature may be
extremely high or low in the systems that have been evaluated. (Specific values
accompany the abstracts and discussion of individual processes.) Oxygen levels
are maintained as high as possible for aerobic treatment systems. Conversely,
anaerobic systems require the absence of oxygen, and a readily accessible car-
bon source, typically methanol, is added to aid metabolism. The absence of toxic
metals is essential in all cases that have been tested.
An aqueous medium is used in activated sludge (biomass), anaerobic diges-
tion, trickling filter, oxygenated lagoons, and practically all systems common
to industrial biological treatment (Atkins, 1972j Gruber, 1975; Gurnham, 1965;
Todd, 1970). If the waste mixes easily with water, contact with the active
microbes will be accelerated. Biodegradation in soil is also possible with soil
incorporation methods (Sanborn et al., 19/7).
The microbes used in biodegradation processes form complex communities
consisting of saprophytic bacteria, fungi, and protozoa with a complement of
autotrophic organisms. The primary organisms are species that are indigenous
to soil and sewage, or mutant strains thereof.
60
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Some recently developed systems duplicate or enhance the functions of
traditional, biological treatment methods and provide information helpful in
an analysis of the potential for biodetoxification of pesticides. Four
laboratory-scale projects and three commercial developments have been examined.
The following discussion of these developments is organized into the four areas:
(1) a description of the traditional techniques available for biological treat-
ment of wastes; (2) an evaluation of related research and recent commercial
developments specific to the detoxification of pesticides; (3) an environmental
and economic assesment; and (4) future research needs.
TRADITIONAL BIOLOGICAL DISPOSAL METHODS
Five of the most widely used methods available for the biological disposal
of pesticides are:
* Activated Sludge
* Trickling Filter
* Oxidation Lagoon
* Anaerobic Digestion
* Soil Incorporation
A short discussion of each of these methods follows.
The activated sludge process consists of aerating the waste stream in the
presence of recycled activated sludge or biomass. This sludge is a source of
acclimated organisms which accelerate the biodegradation of the unwanted sub-
stance.
A trickling filter is a bed of gravel or synthetic medium on which the
waste stream is sprayed and allowed to trickle through. Good air contact is
achieved without high energy costs, and a film of biological growth attaches
itself to the medium. Such a process is frequently a preliminary stage in waste
treatment. .Trickling filters are not as effective as activated sludge but are
less sensitive to shock loads.
An oxidation lagoon is somewhat similar to an activated sludge process
without the sludge return. However, sunlight is necessary for proper operation.
The conversion of C02 to 02 by photosynthetic algae is an important part of
the process. The system works slower than activated sludge and requires greater
space.
61
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Anaerobic digestion is different from the other methods described, as is
suggested by its name. No oxygenation of the digesting fluid takes place. No
new research applicable to pesticide disposal has been encountered in this area;
for this reason, only passing references to anaerobic digestion are made in the
biodetoxification discussion.
Soil incorporation involves spraying the waste on or tilling it into a
land surface. In the topsoil zone the pesticide is then available for biode-
toxification. Because of the overlap with the land disposal section, this
methodology is discussed fully in Section 7.
RESEARCH AND DEVELOPMENT
Much of the research to date on pesticide biodegradation has focused on
the loss of toxicity under agricultural application and runoff conditions
(Sanborn et al., 1977). Little of this work, however, carries over into the
realm of pesticide disposal. The large number of variables involved in microbial
breakdown tends to make each piece of research approach unique, e.g., chemical,
temperature, pH, moisture content, organic composition, and soil or media type.
Even when all of these variables are carefully controlled in a laboratory ap-
paratus, results have questionable value for the operation of landfills and in-
dustrial treatment facilities where complete control is not technically or eco-
nomically feasible.
The most promising methods of biodetoxification involve wastewater treat-
ment systems. The research and development activities that are presently under-
way in this area, therefore, dominate the following discussion.
The research and development discussion is divided into two areas: (1)
laboratory research; and (2) recent developments of commercial waste treatment
systems with potential for pesticide disposal.
Laboratory Research
Current laboratory work with applications to the problems of pesticide
disposal includes:
* Activated Sludge Simulation
* Micropit Disposal
* Tapered Fluidized Bed Reactor
* Use of Immobilized Enzymes
62
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Activated Sludge Simulation—=
The Utah State College of Engineering Water Research Laboratory recently
conducted tests on the biodegradation of 2,4-D and 2,4,5-T under a contract
with the U.S, Air Force (Wachinski et al., 1974). The purpose of the study was
to evaluate the feasibility of using an activated sludge process to dispose of
8.7 million liters (2.3 million gallons) of surplus Herbicide Orange (a 50:50
mixture of 2,4-D and 2,4,5-T).
The experiments were performed in laboratory-scale equipment. Aqueous sys-
tems containing 230, 1,380, and 3,450 mg/liter of the 2,4-D and 2,4,5-T mix-
tures were seeded with sewage, soil, and Phenobac™,£/ respectively. Because the
soil was taken from an Air Force biodegradation test plot with prior Herbicide
Orange contact, it was expected to provide organisms naturally adapted for herbi-
cide breakdown. The apparatus design excluded the possibility of volatile
losses during the 16-day test period.
The results (gas chromatograph data) are summarized in Table 4. The sewage
seed was able to degrade only 13% of the most dilute sample. The adapted soil
showed more activity but was also unable to effect any change in the most con-
centrated samples (3,450 mg/liter). Phenobac™ demonstrated a significant reduc-
tion in all samples (64 to 73%). Incubation temperature was 18°C. The perfor-
mance by the Phenobac™ seed would presumably have been even better if the sam-
ples had been incubated at the producer's optimum growth temperature, 30°G.
TABLE 4. SUMMARY OF HERBICIDE ORANGE BIODEGRADATION LABORATORY RESULTS
Total 2,4-D
and 2,4,5-T
..(ing /JO
230
1,380
3,450
Degradation of
pesticide active
ingredient after
16 days (%)
Sewage soil
13 27
47
-
Phenobac™
69
73
64
Source: Adapted from Wachinski et al. (1974).
a/ Phenobac™ is a commercial, freeze-dried bacterial inoculum, which degrades
phenolic materials. Phenobac™ is described more fully on pp. 76-79.
63
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This method of disposal, however, was not used. The surplus herbicide was
subsequently incinerated at sea on the M/T Vulcanus. As a results a full-scale
activated sludge operation specifically designed for pesticide disposal remains
untried, with the possible exception of proprietary industrial processes
(Atkins, 1972; von RUmker et al., 1974). However, the researchers involved in
the Utah study remain convinced that they have produced a workable plant design
(Adams, 1977).
Micropit Disposal—
Another research project which shows some promise in the biodetoxification
field was initiated early in 1977 at Iowa State University (Hall, 1977). The
objective of this ongoing project is to determine the feasibility of disposing
of pesticides by direct microbial action in small, self-contained disposal pits
suitable for use by farmers and applicators. Three major areas of this effort
are described.
The first portion of the research project is under way at the Horticulture
Research Station, where a 7-year-old concrete disposal pit filled with alternate
layers of gravel and soil is being monitored for biological activity and chemi-
cal degradation of applied pesticides. Four new micropits designed to simulate
the old pit and facilitate sampling have been added at the site. These pits are
all operating under "real world" circumstances with a variety of pesticide
compounds and formulations being introduced into each. For example, the "fruit"
pit receives all of the various pesticide rinse waters and wastes from the
care of the fruit trees at the horticulture station. Figures 13 and 14 present
details of the micro disposal pits and also the original macropit.
The four micropits are labeled in the diagram according to the plants whose
care generated the pesticide waste. Macropit depth ranges from 0.9 m (3 ft) at
the west end to 1.2 m (4 ft) at the east end.
A second group of similar micropit experiments is being conducted at the
Agricultural Engineering-Agronomy Research Center, where an array of 56 micro-
pits (having a slightly different design than those at the Horticulture Station)
are utilized to dispose of specific, commercially available formulations. The
six pesticides under examination are atrazirie, alachlor, 2,4-D butoxyethanol
ester, trifluralin, carbaryl, and parathiono Concentrations of 0»5 and 0.025%
AI (w/w) are included in the testing. Other variables in the experimental de-
sign are aeration at 1 liter/min and nutrient addition providing 0.170 peptone
(w/v). The contents of these pits are also monitored at regular intervals for
microorganisms and residual chemicals»
The third portion of the research, which is discussed here, is a labora-
tory study designed to determine the degree of pesticide loss from aqueous
solution due to volatility. This effort complements the field studies by pro-
viding data on the importance of volatilization in the reduction of pesticide
64
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Ground Level
Perforated
Clay Tile
Rock
Galvanized
Metal Sleeve
212 Liter
Polyethlene
Barrel
Galvanized
Basket
29.2cm (11.5 in.)
20.3cm (8 in.)
35.6cm (14 in.)
55.2cm (1.8ft)
BASKET is galvanized (Electro-plated), one bushel
capacity and has had 75-80 l.lcm (7/16-") holes
drilled in bottom. Bottom of basket is lined with 6.63 cm
0/4") galvanized mesh.
TILE have two rows of holes each. Holes face west
on Bottom tile, east on Top tile. Top tile has
been cut down to 24.8cm (9 3/4") from 31.2cm
(12 1/4"). Tile are 10.2cm (4") I.D.
ROCK is 4.4cm (1 3/4") mixed gravel.
Source: Adapted from Freiburger (1977) and Iowa State
University (1977).
Figure 13. Internal view of pesticide micropit.
65
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N
\
MICRO PITS
ON
3.35m
(11 ft)
Depth
0.9m
(3ft)
8.84m (29.0ft)
MACRO PIT
Depth
1.2m
(4ft)
TOP VIEW
Frt - Fruit
Veg - Vegetable
Orn - Ornamental
Ctl - Control
Source: Adapted from Freiburger (1977) and Iowa State University (1977),
Figure 14. Iowa State University Horticulture Station Disposal Fits*
-------
levels in the micropits. The experimental variables include temperature, rela-
tive humidity, and aeration.
Preliminary work has been done on atrazine, alachlor, and propachlor. Re-
sults indicate that, of these three, atrazine is the most apt to volatilize
under the experimental conditions. Air leaving the test device (1 liter/min,
25°C) contains 1,250 to 1,480 ng/liter of atrazine. Neither relative humidity
changes nor aeration has any significant effect on atrazine volatility. How-
ever, aeration (and, to a lesser extent, low humidity) does enhance the vola-
tility of the other two substances, especially alachlor (Baker, 1977).
Tapered Fluidized Bed Reactor-
Scientists at the Oak Ridge National Laboratory (ORNL) in Oak Ridge,
Tennessee, have developed a tapered fluidized bed bioreactor* Various modifi-
cations of the system have been applied to enzymatic production of hydrogen
gas, microbiological denitrification, and microbiological degradation of coal
conversion aqueous waste—hydrogen sulfide, ammonia, phenols, thiocyanates,
and other hydrocarbons (Lee and Scott, 1977; Rancher, 1977). The similarities
between the treated chemicals and some pesticides, combined with the apparent
success of the method, justify an examination of this research.
The primary structural component of the system is a column whose lower
end is cone-shaped (see Figure 15). Waste material is introduced at the bottom
and follows the tapered walls rotating toward an outflow near the top of the
chamber. The "fluidized bed" is composed of coal particles 0.04 to 0.07 cm
(0.02 to 0.03 in. in diameter). These particles are lifted from the bottom of
the reactor by influx of an aeration gas stream. The tapered shape of the reac-
tor places the greatest velocity on the coal particle at the narrow tip of the
chamber and prevents any of the particles from settling to the bottom. The
widening of the upper portion of the reactor slows the motion within the fluid
and allows only the most buoyant particles—which are overgrown to the point
where they occupy more space than is warranted by the surface area they provide-
to reach the outflow. The coal is thereby suspended in the waste liquid and
serves as a substrate for the growth of the desired organisms or the immobiliza-
tion of an enzyme (Scott and Hancher, 1976).
The microorganisms for the ORNL experiments have been obtained from sev-
eral sources. Local soils have provided an effective mixed culture, including
valuable pseudomonad species. In the experiments studying the degradation of
coal conversion waste, a commercial bacterial seed (Phenobac™) was utilized.
Most of the experiments at ORNL have been carried out with bench-scale
apparatus in glass-walled chambers. The largest reactor constructed to date
is a stainless steel 4.3-m (14-ft) column with a maximum internal diameter
of 0.30 m (1 ft). This tapered bioreactor has demonstrated the ability to re-
duce a 100 rag/liter solution of NH4N03 to 10 mg/liter at a rate of 75 to 115
iiter/min (20 to 30 gal/min).
67
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Reaction
Zone
Gas
Feed
Diss. C>2 Probe
V
Drain
Solid & Biomass
Carry-Over
Liq-Solid
1 1 , .
~ — 'I4ii—
Feed
Source: Adapted from Lee and Scott (1977).
Figure 15. Schematic of tapered fluidized-bed bioreactor system.
68
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Use of Immobilized Enzymes=<=
Some important laboratory-scale work has been performed by Dr. Douglas
Munnecke, formerly with the EPA (Munnecke, 1977; Mlinnecke and Hsieh, 1975).
Emulsifiable parathion was the sole carbon and energy source for mixed bacterial
culture grown from sewage, soil, and water samples. After a 36-day adaptation
period, the culture exhibited maximum growth in a solution containing 5,000
mg/liter parathion and showed only a slight decrease in activity when the para-
thion concentration was raised to 10,000 mgAiter. This higher level represents
an approximation of the concentrations present in wash solutions from pesticide
containers and aircraft spray tanks (Hsieh et al., 1972). Three different bio-
chemical pathways were used by the culture to attack the emulsifiable parathion
under aerobic or low oxygen conditions. The active organisms included five sub-
classes of fluorescent pseudomonads, plus species of Brevibacterium, Azotomonas,
and Xanthomonas. The maximum concentration rate of degradation was 50 mg
parathion/liter per hour.
The success of the culture was, in part, caused by the production of the
enzyme, parathion hydrolase. This enzyme was separated from the active cells
and found to be tolerant of high temperatures (55°G [131°F] for 10 rain with-
out deactivation) and suitable for substrate induction. The mixed bacterial
culture, demonstrated the ability to hydrolyze seven of eight tested organo-
phosphate insecticides. Only fenthion (Lebaycid® ) with three different func-
tional groups was not hydrolyzed. Depending on the pesticide, biochemical de-
toxification rates when using 20 mg protein/liter were 11 to 2,450 times faster
than in chemical detoxification procedures using O.lN NaOH.
The significance of this series of experiments may be summarized as fol-
lows: (1) a toxic organophosphate insecticide, parathion, was successfully
biodegraded to simpler phosphoric acids and phenols; (2) the microbial enzyme
produced was able to degrade eight additional organophosphate pesticides; and
(3) the enzyme which was capable of hydrolyzing these pesticides was isolated
and found to be stable outside the parent cell.
Subsequently, Munnecke continued to study the potential use of enzymes in
a pesticide disposal method. This further effort utilized immobilized enzymes
produced, as previously discussed, by the growth of a mixed bacterial culture
on a parathion substrate (Munnecke, 1977). Munnecke immobilized the desired
enzymes on Jena laboratory glass using the azide coupling method of Mason and
Weetal (1972). The hydrolase preparation was then placed in columns to evaluate
its ability to hydrolyze organophosphate solutions and test its response to
fluctuations in pH and temperature.
Results showed that the system was capable of hydrolyzing nine organo-
phosphates including triazophos and EPN. The immobilized enzymes showed a broad
pH optimum between 8.5 and 9.5, similar to the behavior of the free enzyme.
Stability under the influence of temperature change was also found to be about
69
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the same as had been previously observed in the free enzymes* However, the im-
mobilized preparation was slightly more stable than the free enzymes at tem-
peratures beyond 45°C.
• •
From 1976 to the summer of 1978 Dr. Munnecke worked with Bayer
Farbenfabriken of Leverkusen, West Germany, to determine the feasibility of
using immobilized or free enzymes for the detoxification of industrial pesti-
cide -production, wastes » Pr e 1 iminary -results showed_that free enzymes can be
used to detoxify parathion in formulations and production wastewaters as well
as in pesticide containers* Current research is in progress to scale up to
40,000 liters of batch fermentations of mixed bacterial cultures*
Promising Commercial Technologies
Several new biological disposal systems have been developed which dupli-
cate or enhance the functions of trickle filters or activated sludge reactors
and require much less space* Three of the systems are:
* Rotating Disc
* Fluidized Bed Reactor Treatment
* Mutant Bacterial Inoculum
The developers of each of these processes claim the ability to handle any bio-
degradable waste (Antonie, 1977; Hancher, 1977; Owens, 1977; Zitrides, 1977).
Considering the evidence demonstrating the successful biodegradation of phenolic
wastes (Chu and Kirsch, 1972; Cserjesi, 1967; Ide et al., 1972; and Zitrides,
1977), and the widespread use of trickle filters and activated sludge processes
by the pesticide manufacturing industry (Atkins, 1972 and von Rumker et al.,
1974), an examination of these new systems is justified, despite the fact that
they remain largely untried as pesticide disposal techniques.
Biodisc treatment-
Rotating disc treatment of municipal and industrial waste has been common
i*ti Europe for about 18 years (Autotrol, 1971). The basic process is a form of
thin film biodegradation in which large plastic discs are half submerged in
the wastewater. Aerobic microorganisms indigenous to the effluent colonize the
disc surfaces and receive (maximum) oxygenation as the discs are slowly rotated.
By arranging a line of discs on a single shaft and then placing many of these
units in series, a well-aerated surface requiring relatively little space may
be provided for biological activity.
The Biosurf™ process illustrated in Figure 16 has been employed in over
200 municipal and industrial installations across the United States and by
industrial customers in Canada, Europe, and Japan (Autotrol, 1976). In many
70
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Cross section of alternating flat
and corrugated polyethylene sheets
in one disc.
Functioning units arranged in series
and anclosed by fiberglass reinforced
p Us tic.
single Bio-Surr® unit.
A schematic illustration of a Bio-Surf®1 wastewater treatment plant.
, PLASTIC COVERS >
SLUDGE PUMP
\
SECONDARY CLARIFICATION UNDER FALSE BOTTOM LJ 1 EFFLUENT
Source: Adapted from Autotrol (1976).
Figure 16. The Bio-Surf™ process.
INFLUENT
FROM
PBETRE4TM6NT
71
-------
cases the Autotrol equipment has been added to existing facilities to upgrade
the effluent treatment system. Waste streams consisting of municipal sewage,
refinery wastes, paper and pulp wastewater, acid mine drainage, and food
processing waste have been upgraded by Biosurf™ treatment (Autotrol, 1976;
Autotrol, 1974). Anaerobic conditions can be produced by enclosing a completely
submerged Biosurf™ system and adding a carbon source, typically methanol
(Autotrol, 1974). x
Fluidized Bed Reactor—
Ecolotrol, Inc., of Bethpage, New York, is currently selling a full-scale
biological fluidized bed process. In design, the Hy-Flo™ system is very similar
to that of the ORNL. However, the main reactor is not tapered, and the particle
growth medium is sand, not coal.
c
The process maintains a large population of microorganisms and makes pos-
sible more rapid treatment than conventional biological methods, i.e., acti-
vated sludge and/or trickle filter. No clarifier is required with an Ecolotrol
system, and the manufacturer claims 93.0 nr (1,000 ft ) of microbial surface
area per every 28.1 m3 (1,000 ft3) of tank water (Owens, 1977). Hy-Flo™ units
have been used on municipal sewage (Jeris et al., 1977) and, on a pilot scale,
for processing several industrial waste streams including pharmaceutical wastes
and petroleum tank truck wastes (Owens, 1977).
Mutant Bacterial Seed—
Phenobac™ is a freeze-dried, biochemical preparation containing mutant
bacteria and substances to enhance their growth. The product has been developed
by Worne Biochemicals, Inc., of Berlin, New Jersey, for degradation of the fol-
lowing compounds: benzene derivatives; phenols; cresols; naphthalenes; amines;
alcohols; synthetic detergents and surfactants; lignin and cellulose derivatives;
gasoline; kerosene; cyanides (properly diluted) and other toxic wastes from
refineries, steel mills, pulp mills, and other chemical, textile and food proc-
essing plants (Phenobac™, 1977).
The product is marketed by the Polybac Corporation. Despite the apparent
success of this microbiological technology, Polybac Corporation presently has
no serious competitors (Zitrides, 1977).
The Polybac literature.(Phenobac™, 1977) states that many possibilities
exist for Phenobac™ use in organic chemical plants and refineries. A small
portion of the technical data published by Polybac, selected for their appli-
cability to pesticide waste streams, is shown in Table 5.
72
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TABLE 50 BIODEGSADATIONABILITY OF PHENOBAC™ AT 30°C (86°F)
Initial Treatment
Compound and concentration Percentage time
procedure (mg/l) destruction (hr)
Halophenols (mutant pseudomonas, activated sludge)
phenol 500 100 10
2j,4-dichlorophenol 200 100 35
pentachlorophenol (PGP) 200 26 120
2,3s,5°trichlorophenol 200 100 55.
Aryl Amines (mutant aerobacter, oxidation lagoons)
o=dianisidine 500 100 40
m=toluidine 500 100 10
2,4,6-trichloroaniline 500 100 30
aniline 500 100 15
Aryl Halides (mutant pseudomonas, biological filter/activated sludge)
I,2,4s5-tetrachlorobenzene 200 80 120
1,3,5-trichlorobenzene 200 100 50
m°dichlorobenzene 200 100 30
hexachlorobenzene 200 0 120
Sources Phenobac™ (1977)
73
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The product may be added to new or existing biological, aerobic wastewater
treatment systems. A wide variety of waste stream conditions can be tolerated
by Phenobac™:
pH 4.5 to 9.5
Dissolved Q£ 1.0 ppm - no maximum
C/N/P ratio 100/5/1
Temperature 10 to 40°C (50 to 104°F)
One recent demonstration of the utility of Phenobac™ is offered by its
performance for Mobay Chemical Company at the New Martinsville, West Virginia,
location (Polybac, 1977). The New Martinsville plant produces a number of haz-
ardous chemicals including aniline, seven organic isocyanates, and toluene-2,4-
diamine (Stanford Research Institute, 1977). None of the compounds are pesti-
cides. However, the species noted represent precursors of pesticide compounds.
Following a shutdown caused by the natural gas shortage during the winter
of 1977, Mobay's activated sludge process was reduced to the point that it con-
tained only 5% of the biomass expected during normal operation. The capacity of
the plant was 21 million liters per day (5.5 million gallons per day). The waste
stream contained a variety of aromatic and aliphatic organic compounds. Efforts
to revive the process via the addition of sludge from a nearby plant and an
easily degradable waste feed failed.
At that point, a Phenobac™ seed was introduced with the following re-
sults: the seed was initially added at a rate of 5.4 kg/million liters (50
Ib/million gallons) and gradually reduced to 0.11 kg/million liters (1 lb/
million gallons) as the microbial population stabilized. The plant was under
control after 15 days of Phenobac™ application and fully effective after 4
weeks. Table 6 illustrates the recovery of the percent reduction by listing
the change in five wastewater parameters measured in the influent of the treat-
ment system after the problem arose and during the several months required to
stabilize the process.
Further evidence of the potential value for pesticide disposal provided
by a mutant bacterial seed is suggested by the fact that two of the current
research efforts reviewed in the course of this study incorporated Phenobac™
in their work (Lee and Scott, 1977; Wachinski, 1974).
POTENTIAL IMPACTS
The potential environmental and economic cost impacts of biological dis-
posal technologies are discussed below.
Potential Environmental Impacts
Due to the absence of any documented full-scale pesticide disposal opera-
tions using biological treatment, little can be said about the resulting
74
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TABLE 6. MOBAY FACILITY RECOVERY WITH PHENOBAC™
Figures represent average values in mg/£.
The introduction of Phenobac™ occurred during March.
Parameter Month Influent Effluent % Reduction
Phenol
Oil and grease
COD
BOD
TOG
February
March
April
February
March
April
February
March
April
February
March
April
February
March
April
11.71
11.51
23.39
26.2
21.1
31.6
860
684
717
170
259
312
181
175
228
2.88
0.659
0.433
19.1
14.6
13.9
574
346
231
83
42
16
116
90
79
74.5
94.3
98.1
27.1
30.5
56.0
33.3
49.4
67.8
51.2
83.8
94.9
35.9
48.6
65.4
Source: Adapted from Polybac (1977).
75
-------
environmental problems. Volatile losses of pesticides from activated sludge
or associated open-air processes would be a potential hazard, and air monitor-
ing would be advisable. Similarly, effluent released during any period of dis-
rupted operation could pollute the receiving waterway. Monitoring of effluents,
including bioassay, is advisable. The microbial community in a pesticide treat-
ment network presumably would not contain pathogenic organisms, thus avoiding
the health hazards inherent with municipal waste management. The use of a
sewage seed could eliminate this advantage. Any of the various biological meth-
ods would produce a sludge requiring disposal, probably by landfill ing of the
dewatered solids. The residual toxicity contained in such a waste remains un-
determined. Further comments on environmental impact cannot be justified due
to the inadequate data base.
Potential Economic Impacts
Though pesticide manufacturers may employ biological processes in the treat-
ment of their waste streams, specific data describing such private operations
and their associated costs are not made public. Because there are no comparable
facilities in the municipal sector, cost figures representative of full°scale
plants capable of treating pesticides are difficult to ascertain.
The researchers at Utah State University (Wachinski et al., 1974) designed
a 7.6 million liters per day (2 million gallons per day) pure oxygen activated
sludge plant. They estimated that it would cost between $1 million and $2 mil"
lion to construct and operate during the 1-year period required to eliminate
an 8.7 million liter (2.3 million gallon) stockpile of Herbidide Orange. The
2-acre treatment site would have included:
1. Activated sludge (with pure 02 and Phenobac™).
2. Anaerobic digestion.
3. Sludge drying beds.
4. Activated charcoal or aerated holding pond for effluent, prior to
oce^n outflow.
The process was expected to produce a liquid effluent that would meet drinking
water standards. It is important to note that the system never materialized and
remains unproven.
76
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The total installation charges for a Biosurf™ secondary treatment system
capable of handling 38 million liters per day (10 million gallons per day) are
estimated to be around $0.05/liter per day ($0.17/gallon per day) or $1.7 mil-
lion (Autotrol, 1976). A plant handling 380 million liters per day (100 million
gallons per day) would be a fraction of a penny less expensive per million
liters per day, and a plant handling 3.8 million liters per day would be $0.0267
million liters per day ($0.10/million gallons per day) more expensive. Operating
expenses are not available. However» Autotrol literature indicates significant
horsepower savings over conventional activated sludge processes (Autotrol, 1976).
Though not a complete process by itself, Phenobac™ may be used to seed
many varieties of biological treatment systems. Costs range from $4/million
liters per day ($15/million gallons per day) for a 38-million liter per day
(10 million gallons per day) operation to $26/million liters per day for a 150-
million liter per day (40 million gallons per day) operation.
The most prominent limitation encountered in approximating the costs for
biodetoxification of pesticides is the fact that the most promising approaches-
activated sludge with a mutant microbial seed, biodisc, fluidized bed—have not
been given a pilot-scale trial. Another problem is the convention of rating
plants by million gallons per day capacities and not specifying the concentra-
tion and nature of the example influent. A pesticide solution could not be ex-
pected to be comparable with the average municipal sewage influent.
FUTURE RESEARCH NEEDS
There are insufficient data to indicate the effectiveness of any biologi-
cal method for the disposal of any pesticide on a full-scale basis. For this
reason, further testing is warranted, particularly using mutant bacterial
inoculum in combination with existing and newly developed treatment systems.
The majority of registered pesticides have not been examined for potential
biological disposal. Data are not available on the performance of a full-scale
biological disposal system for pesticide wastes. The environmental impact of
biological pesticide disposal due to volatile losses, sludge burial or incinera-
tion, and toxic substances in wastewater effluents remains undetermined.
This lack of data suggests that future research should be directed into
six important areas. First, volatile losses from biological treatment need to
be quantified and assessed. The high vapor pressures characteristic of many
organic pesticides (von Rumker et al., 1974) suggest the possibility of evapora-
tion, and aeration typical of biodetoxification processes would encourage such
a tendency. Airborne escape of chemicals or their breakdown products must be
controlled if they represent a health or an environmental hazard.
Second, an expanded effort in the development of the most promising tech-
niques is warranted. MUnnecke's work on the breakdown of organophosphates with
immobilized enzymes (Munnecke, 1977) stands by itself as the only current
77
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application of this methodology to pesticide disposal* Similarly, the use of
mutant microbial cultures is being developed and marketed by a single company
(Zitrides, 1977). (This apparent lack of cooperation and/or competition among
researchers and companies may delay the arrival of the best disposal tech-
nology*)
Third, the use of pilot plants to attempt the biodegradation of pesti-
cides is the next logical step. The performance of trickling filter/activated
sludge, oxidation lagoon, rotating disc, and immobilized enzyme systems should
be evaluated* Mutant microbes should also be included in the testing*
Fourth, the use of integrated disposal systems that take advantage of the
best properties of different systems should be considered.
Fifth, the extent of residual toxicity in by-product sludges should be
ascertained* Alternative means of disposing of such waste solids should be
examined*
Sixth, the majority of classes of pesticides have not been tested to deter-
mine their susceptibility to biological disposal. Setting the various low con-
centration soil incorporation studies (Sanborn et al., 1977) to one side be-
cause they have little bearing here, only the specific phosphorus- and halogen-
containing pesticides indicated in Section 5, Biological Methods, have been
examined in terms of their potential for large-scale bidconversion to nontoxic
compounds. Much additional work is needed to determine the feasibility of
biological disposal for the many untested pesticides*
78
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REFERENCES
Adams, V. D. Utah Water Research Laboratory, Utah State University. Personal
communication to F. Hopkins, Oct. 26, 1977.
Antonie, R. Autotrol Corporation - Bio-Systems Division. Personal communica-
tion to F. Hopkins, Oct. 14, 1977.
Atkins, P. R. The Pesticide Manufacturing Industry - Current Waste Treatment
and Disposal Practices. Environmental Protection Agency, Project No. 12020-
FYE. NTIS Catalogue No. PB-211129. Jan. 1972.
Autotrol Corporation, Bio-Systems Division, Milwaukee, Wisconsin. Applica-
tion of Rotating Disc Process to Municipal Wastewater Treatment. Project No.
17050 DAM, Contract No. 14-12-810, Office of Research and Monitoring, Environ-
mental Protection Agency. Nov. 1971.
TM
Autotrol Corporation, Bio-Systems Division, Milwaukee, Wisconsin, Biosurf
Process Information Bulletin, Biosurf™ Pilot Plant Program. 1974.
TM
Autotrol Corporation, Bio-Systems Division, Milwaukee, Wisconsin. The Biosurf
Process. 1976.
Baker, J. L. Annual Report. October 1976 - October 1977. EPA Grant R804533010.
Department of Agricultural Engineering. Iowa State University, Ames, Iowa.
Oct. 19, 1977.
Chu, J. P., and E. J. Kirsch. Metabolism of Pentachlorophenol by an Axenic
Bacterial Culture. Applied Microbiology, 1033-1035, 1972.
Cserjesi, A. J. The Adaptation of Fungi to Pentachlorophenol and its Bio-
degradation, Canadian Journal of Microbiology, 13:1243-1249, 1967.
Freiburger, L. Predoctoral Research Associate at the Iowa State University
Horticulture Station. Personal communication with F. Hopkins of MRI on July 5,
1977.
Gurnham, F. C. Editor. Industrial Wastewater Control, Academic Press, New York
and London, 1965.
79
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Gruber, G. I. Assessment of Industrial Hazardous Waste Practices, Organic
Chemicals, Pesticides, and Explosives Industries. Compiled by TRW Systems
Group under Contract/Grant No. EPA-68-01-2919 for the Office of Solid Waste
Management Programs. Apr. 1975.
Hall, C. Head of the Department of Horticulture, Iowa State University. Per-
sonal communication to F. Hopkins. June 9, 1977.
Hancher, C. W. Oak Ridge National Laboratory. Personal communication to
R. Wilkinson. Oct. 11, 1977.
Hsieh, D. P. H., T. E. Archer, D. M. Munnecke, and F. E. McGowan. Decontami-
nation of Noncombustible Agricultural Pesticide Containers by Removal of
Emulsifiable Parathion. Env. Sci. Tech., 6(9):826-829, 1972.
Ide, A., Y. Niki, F. Sakamota, I. Watanabe, and H. Watanage. Decomposition of
Pentachloraphenol in Paddy Soil. Agricultural and Biological Chemistry, 36:
1934-1944, 1972.
Iowa State University, Second Quarterly Report on Micropit Pesticide Disposal
(unpublished), Horticulture Department, Jan. 31, 1977 - Apr. 11, 1977.
Jeris, J. S., R. W. Owens, and R. Hickey. Biological Fluidized-Bed Treatment
for BOD and Nitrogen Removal. J. Water Pol. Cont. Feder., 816=831, May 1977«>
Lee, D. D., and C. D. Scott. A Tapered Fluidized-Bed Bioreactor for Treatment
of Aqueous Effluents from Coal Conversion Processes. Presented at the 70th
Annual Meeting of the American Institute of Chemical Egnineers, New York,
Nov. 13-17, 1977.
Mason, R. D., and H. H. Weetall. Invertase Covalently Coupled to Porous Glassi
Preparation and Characterization. Biotechnology and Bioengineering, 14:637°
645, 1972.
Munnecke, D. M., and D. P« H. Hsieh. Development of Microbial Systems for the
Disposal of Concentrated Pesticide Suspensions. Meded. Fac0 Landbouwwet.
Rijksnniv. Grant 40 (2, Pt. 2), 1237-1247 (1975); Chem. Absos 84S 131127d,
1976*
Munnecke, D. M. Properties of an Immobilized Pesticide - Hydrolyzing Enzyme.
Applied Environmental and Microbiology, 33(3):503-507, 1977.
Owens, R. W. Ecolotrol, Inc. Personal communication to F. Hopkins. Oct. 18,
1977.
80
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Phenobac 0 Technical Data Sheet 1377A0 Published by Polybac Corporation,
New York, New York, 1977.
Polybac Corporation, New Yorko Mutant Bacteria Add Shock Load Tolerance at
Mobay Chemical Waste Treatment Plant. Sales Promotion Literature. 1977.
Sanborn, Jo Roj, B. M. Francis, and R. Lo Metcalf. The Degradation of Se-
lected Pesticides in Soil: A Review of the Published Literature. EPA-600/9-
77-022, Aug» 1977o
Scott, Co Do and C» We Rancher. Use of a Tapered Fluidized-Bed as a Continu-
ous Bioreactor© Biotechnology and Bioengineering, 18:1393-1403, 1976.
Stanford Research Institute. Directory of Chemical Producers. Menlo Park,
California, 1977.
Todd, K« D«, Editors The Water Encyclopedia. Water Information Center.
Port Washington, New York. 1970»
von RUmker, R., E® We Lawless, and Ao F. Meiners. Production, Distribution,
Use and Environmental Impact Potential of Selected Pesticides. Final Report
by MRI and RvR Consultants under Contract No. EQC-311 for the Council on
Environmental Quality. EPA-540/1-74-901, 1974.
Wachinski, A. M., V. D. Adams, and J« H. Reynolds. Biological Treatment of
the Phenoxy Herbicides 2,4-D and 2,4,5-T in a Closed System, Research Report
to the UcS« Air Force Submitted by the Utah Water Research Laboratory, Utah
State University, Maro 1974.
Zitrides, To G* Polybac Corporations Personal communication to F» Hopkins,
Octo 25, 1977.
81
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SECTION 6
-PHYSICAL AND CHEMICAL DISPOSAL- METHODS
INTRODUCTION
This section of the report describes and discusses current research and
development on physical and chemical disposal methods for pesticides and re-
lated hazardous materials. The specific methods discussed apply to dilute
solutions of pesticides in process wastewaters, to concentrated pesticide
AI, and to finished pesticide formulations* (The last category is particularly
applicable to field disposal problems.)
The existing data base is the focus of the review, but environmental and
economic cost impacts of alternative methods are also assessed. The section
closes with an overview of each disposal method and an outline of future re-
search needs. References are given at the end of the section.
Each disposal method is categorized by the phase or phases in which de-
toxification or destruction takes place: gas, liquid, liquid-solid, and
catalytic liquid phases. Within each category, individual disposal methods are
discussed in alphabetical order in an attempt to minimize bias. Other organi-
zational arrangements are possible, e.g., quality and quantity of fundamental
data, level of method complexity and associated apparatus, estimated prac-
ticality for field disposal, etc. But none of these alternative arrangements
offer distinct advantages over alphabetization.
RESEARCH AND DEVELOPMENT
•
The disposal methods examined include:
* Gas phase methods
. Microwave plasma destruction
. Photolysis
* Liquid phase methods
• Activated carbon and resin adsorption
• Molten salt baths
. Ozonation techniques
. Wet air oxidation
82
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* Liquid-solid phase method
. Chemical fixation
* Catalytic liquid phase methods
• Catalytic dechlorination
• Reductive degradation
GAS PHASE DISPOSAL METHODS
Two gas phase methods for the detoxification of pesticides are microwave
plasma destruction and photolysis* Each is discussed below*
Microwave Plasma Destruction
Lockheed Missiles and Space Company, Palo Alto Research Laboratory (LPARL),
is currently developing a detoxification method for hazardous materials, in-
cluding pesticides, based on microwave plasma destruction of organic materials
^Oberacker and Lees, 1977). The research efforts have been expanded from the
bench-scale level through a demonstration unit which can successfully detoxify
hazardous organic compounds at the rate of 0.45 to 3.2 kg/hr (1 to 7 Ib/hr).
The EPA has now provided additional support of this work to include fabrication
and demonstration of a 4.5 to 13.5 kg/hr (10 to 30 Ib/hr) apparatus with the
long-range goal of developing a 40 to 50 kg/hr (—100 Ib/hr) version which
would then have wide-ranging applications and allow continuous operation by
virtue of an improved pumping system.
Figures 17 and 18 present schematic diagrams of the microwave plasma unit
and related components. Commercially available, standard glass apparatus and
electronic hardware and accessories were used to construct the demonstration
microwave reactor. The microwave power sources are two 2.5-kw power supplies
which supply energy at 2,450 MHZ. The energy is fed through rectangular trough
wave-guides and "tuned" or "focused" prior to entering the applicator assembly
which surrounds the quartz reaction tube.
Analytical instrumentation to monitor the detoxification process includes
a continuous sampling residual gas analyzer (a low resolution mass spectrom-
eter) placed in line between the reactor tube outlet and the ice water cold
trap, and auxiliary instrumentation, an infrared spectrophotometer and a gas
chromatograph. Other analytical and mass balance data were obtained by standard
quantitative analytical techniques.
The unit operates as follows: The organic hazardous waste material is
added to the apparatus as a pure liquid, as a slurry or solution in water or
methanol, or as a compressed cake or pellet. The apparatus operates at a re-
Iduced pressure (10 to 100 torr pressure) with a carrier gas and rather simple
83
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Pesticide
-Dropping
Funnel
Tuning
Unit
\
\
1st
It!
Microwave
Power Source
Microwave
Applicator
Microwave
Power Source
Receiver
• Plasma
Reactor
Tube
Flow Meters
C>2 Supply Alternate
Gas Supply
3-Woy Stopcock
Manometer
Cold Trap
•Vacuum Pump
Throttle
Valve
Cold Trap
Source: Adapted from Bailin and Hertzler
(1976).
Figure 17«, Schematic of microwave plasma system.
84
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Carrier Gas
Liquid Plus Carrier Gas
Teflon
Needle-Valve
Stopcock
Quartz
Reactor Tube
Quartz
Basket & Fibers
Teflon Gasket Quick
Disconnect
1
First Plasma
Zone
Traps & Vacuum Pump
Source: Adapted from Bailin and Hertzler
(1976).
Figure 18. Quartz mesh basket within microwave plasma reactor.
85
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devices to admit and control the addition rate of the sample to the plasma reac-
tor section*
Samples of hazardous material to be detoxified are introduced into a drop~
ping funnel, i.e., a volumetric flask and stopcock assembly held above the reac=
tor tube. Carrier gas may be introduced above the hazardous material dropping
funnel*
The hazardous material moves under the combined forces of gravity and a
carrier gas (oxygen, oxygen-argon, or steam) through a quartz reaction tube
filled with quartz Raschig rings (or alternately, the reaction tube contains
a quartz basket filled with quartz fibers)* The purpose of the rings or fibers
is to increase the residence time of the hazardous material in the reaction
tube* Reaction products may be contained in traps cooled with ice water or
liquid nitrogen which is placed between the reaction tube and the vacuum pumpo
Destruction of the hazardous material takes place in the reaction tube
by application of microwave radiation, which generates an ionized carrier gas0
The microwave-induced electrons then react with neutral organic molecules to
form free radicals which ultimately dissociate and/ or react with oxygen to form
simple reaction products, e<>g., S02, G02, CO, H20, HPC>3, COCl2» C120S Br2»
Br02» or in case of phenylmercuric acetate, free mercury metal • A Tesla coil
is generally used to ignite the discharge.
After destruction of the hazardous material, the reaction products as
gases, vapors, and readily condensable material pass into an ice water bath
and then to a liquid nitrogen cold trap before the carrier gas enters the
vacuum pump.
The net overall reactions for destruction of malathion and Kepone® are
as follows:
02 - Ar + +
Energy (100 to 10,000 MHZ) ,„ .' > 09 + Ar + 2e~
(Carrier gas .*-. , . , ,
. (plasma or ionized gas;
mixture)
Plasma + C10H1906PS2 + 1502 -> 2S02 + 10C02 + 9H20 + HP03
(malathion)
Plasma + CiQClioO + 702 -»• 5C02 + 5CO + 5C12
(Kepone®)
Production of intermediate free radicals from the organic molecules is. essen=
tial in these reactions but is not shown in the net overall chemical reaction.
Table 7 presents a summary of oxygens-plasma reaction results for three
classes of pesticides, PCB5ss and UoSo Navy Red Dye, a pyrotechnic smoke mixtureo
86
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TABLE 7. SUMMARY OF MICROWAVE OXYGEN-PLASMA REACTIONS
Hazardous materials
Halathlon
Cythion®ULV
Halathlon
Cythlon® UtV
PCB
Aroclor® 1242
PCB
Aroclor® 1242
PCB
Aroclor® 1254
PMA
Troysan® PMA-30
CO PMA
»-J Troysan® PMA-30
PMA
Troysan® PMA-30
Kepone® 80/20
207. methauol
solution
Kepone® 80/20
10% solids
aqueous s lurry
Kepone®
2 to 3 g
solid discs
U.S. Navy Red Dye
Microwave Feed
power, rate,
kw kg/hr
3.7 0.5
4.7 0.5
4.6 0.27
4.2 0.5
4.5 C.18
4.6 1.0
4.0 2.4
4.3 3.0
4.6 0.73
4.6
4.6
4.6 0.5 slurry;
0.09 equiv-
alent
solids (not
optimized)
Oxygen
Pressure gas £low,
Pa (torr) l/tir
3,700-6,100 361
(28-46)
3,700-4,000 480
(28-30)
2,300-4,700 323
(17-35)
2,500-4,800 395
(19-36)
1,700-3,300 360
(13-25)
16,000-1.8,700 960
(120-140)
13,300-16,000 792
(100-120)
13,300-16,000 792
(100-120)
7,200 720
(54)
5,300 None
(40)
930 90
(7)
4,600-7,900 300
(15-60)
Conversion
Reactor packing (I)
Wool plugS/ 99.998
Wool plug 99.999
Wool plug 99
Wool plug 99
Solid rings!/ 99
Raschlg rings3.' Est. 99.99
Raschig rings Est. 99.99
Raschig rings Est. 99.99
Raschlg rings 99
Raschig rings 99
Raschlg rings 99
Raschlg rings 99.99
Sources: Bailln and llertzlcr (1976) and Bailln (1977).
£/ Quartz.
-------
This constitutes the summary of work performed at LPARL on the largest operating
microwave plasma apparatus as of August 1977. (Current work involves construc-
tion of a 4.5 to 13.5 kg/hr unit.)
The table indicates a high order of detoxification for malathion, PCB's,
Kepone®, phenylmercuric acetate, and Navy Red Dye of at least 99+%• Feed rates
are from 0.18 to 3.0 kg/hr. Pesticides and other hazardous material includes:
malathion as an ULV liquid formulation using the quartz basket technique with
a quartz wool" bundlerPCB's a^s liquids (ArocTor®1242);phenylmercufic; acetate
(PMA-30) as a 30% w/v solution in methanol; and Kepone® (80% as a clay supported
mixture) as solid press cakes of 2 to 3 g. Residence time in the reactor tube
varies from 0.5 to 1 sec for liquid solutions and 10 to 30 sec for solid press
cakes of Kepone® (Bailin and Hertzler, 1976).
The most recent microwave plasma detoxification studies by LPARL have been
concerned with the decomposition of a U.S. Navy Red Dye (Bailin, 1977a). This
material, a marine smoke and illumination signal, consisted of a mixture of
xylene-azo-0-naphthol (457o by weight), 1-methylaminoanthraquinone (157<>), and
other components: sucrose, graphite, potassium chlorate, and a silica binder.
Of these chemicals, the first is a known carcinogen, and the second is sus-
pect.
The mixture was subjected to the microwave detoxification process with
oxygen as the reactant gas. Based on, the quantity of starting material, gases
analyzed, and a solid residue obtained, a 99.99+% conversion to gaseous prod-
ucts was accomplished. Final products included polyaromatic hydrocarbons (<
2 ppm), with essentially no dye starting materials remaining (< 5 ppm) as shown
by various analytical techniques, including visible/UV spectrophotometrys
ultraviolet fluorescence, and combined GC/MS. Other details may be found by
consulting Table 7.
Several vacuum feed techniques were evaluated for the dye, which included
different physical forms, as a powder, a solution, and a water slurry* None of
these techniques were satisfactory for high throughput processings ioeo, mul-
tiple *kilograms per hour. It is recognized that other positive displacement
methods to obtain high, continuous, and reproducible flow rates will be re-
quired for materials exhibiting non-Newtonian flow.
Finally, as part of the entire program, a survey of highly toxic mate-
rials which are stored within the continental United States has been per-
formed (Bailin, 1977b). On the basis of information from 6 of the 10 EPA Regional
Offices and other sources, a catalog of carcinogens, nerve poisons9 and acutely
toxic organometallic compounds and heavy metal complexes was compiled. Much of
this material is present in "low poundage" quantities, ~50 kg (100 Ib) and
thus is amenable to the unit currently under test which may process 5 to 15 kg/
hr (10 to 30 Ib/hr).
88
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Photolysis
For convenience, we have chosen to categorize photolysis as a gas phase
process potentially occurring totally in the atmosphere or at any atmospheric/
surface interface, e.g., air/soil, air/water, etc. A vast amount of literature
describing photolytic degradation studies of pesticidal chemicals is available.
Early investigators studied the photodecomposition of pesticides on soils,
crops, glass plates, and filter paper. Perhaps the earliest author to compile
a catalog of the effects of UV light, Mitchell reported on 141 pesticidal
chemicals (Mitchell, 1961). Other excellent reviews of this field are by Crosby
and Li (1969), Plimmer (1970, 1972, 1977), Rosen (1971), Watkins (1974), and
Crosby (1977).
The laboratory apparatus required to study photodecomposition of pesticides
is relatively simple and readily available. Both low and medium pressure mercury
vapor arc lamps are conmonly used. Low pressure lamps radiate about 90% of their
energy in a band near 254 run, and medium pressure lamps emit strong bands at
366 nm (16%) and at 313 nm (9%). Various light sources and associated apparatus
have been discussed by Calvert and Pitts (1969), Crosby .and Li (1969), Crosby
(1969), and Watkins (1974).
- The MRI project team has utilized these sources of literature and, in addi-
tion, has been in touch with Crosby and Plimmer to receive reports and to
discuss the latest experimental work and applications of photolysis to the
destruction or detoxification of pesticides and other hazardous waste materials.
If photolysis is to occur, the pesticide molecule must first absorb light
energy above 290 nm or receive energy from another molecule through an energy
transfer process (photosensitization). In addition, the environment surround-
ing this pesticide molecule plays an important role in photochemical behavior.
If photolysis does occur, the resulting products may be more or less toxic
than the original product; examples for each possibility are known. For example,
photodieldrin is more toxic toward flies than is dieldrin (Henderson and Crosby,
1967). Further, photolysis occurs in competition with other physical, chemical,
and biochemical processes.
The initial step of the photolytic reaction usually involves homolytic
fission of the parent molecule to form free radicals. These unstable inter-
mediates react further with the solvent, other organic molecules, inorganic
species, radicals, etc. The product may be a complex mixture in which iSom-
erization, substitution, oxidation, or reduction processes have occurred.
Of particular importance is photosensitization by which certain molecules
absorb light energy and transfer it to the parent pesticide molecule which
•would not otherwise absorb light at that wavelength. An important example of
photosensitization is the photolysis of chlorodioxins by interaction with a
hydrogen donor solvent molecule (Crosby, 1977; Homberger et al., 1976).
89
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A second example of photosensitization of pesticide molecules is that of
the photolysis of 3,4-dichloroaniline, which occurs as a soil metabolite of
the herbicide propanil (1,1-dichlorophenylpropionanilide). In benzene solution
the dichloroaniline molecule is not photochemically active under irradiation
at 260 nm. However, irradiation of dichloroaniline at the same wavelength in
the presence of benzophenone produces several chlorinated azobenzene species
(Plimmer and Kearney, 1969). Similar azobenzene derivatives were obtained from
3,4-dichloroaniline by irradiation in water in the presence of flavin mono-
nucieotide (Rosen et al., 1970). ~
Pesticides undergo several different types of photolytic reactions includ-
ing: ring fission (Plimmer et al., 1967); condensation (Rosen et al., 1970;
Plimmer and Kearney, 1969); bond rearrangement (Benson, 1971); reductive loss
of chlorine (Plimmer and Hummer, 1969); replacement of chlorine by hydroxyl
group (Crosby and Tutass, 1966); and replacement of halogen by phenyL group
(Ugochukwu and Wain, 1965). Figure 19 taken from Plimmer (1972) presents ex-
amples of these reaction types for various pesticides.
Photolysis of chlorinated hydrocarbon pesticides has been previously
mentioned in this subsection. Reactions in the presence of UV light for chlo-
rinated hydrocarbons include dieldrin to form photodieldrin, which is a bridged
isoraer of the parent compound and contains the same number of chlorine atoms.
Other products include a chlorohydrin and various partially dechlorinated
species and bridged isomers. Heptachlor similarly forms a cage molecule while
DDT (dichlorodiphenyltrichloroethane) yields the more volatile DDE (dichloro-
diphenyldichloroethylene) and other products.
In the general class of N-methylcarbamates, e.g., carbaryl, the ester
linkage is broken, yielding 1-naphthol and toxic methyl isocyanate. Photoly-
sis of propham (isopropyl N-phenylcarbamate) forms a number of products, in-
cluding phenyl thiocyanate, aniline, 2-propanol, propylene, and carbon dioxide.
Halogenated acids and phenols when subjected to photolysis can yield a
series of hydrogenated or hydroxyl substituted products, some of which may be
more volatile than the parent molecule. For example, 4-chlorophenoxy acetic
acid photolyzes to produce benzaldehyde, benzyl alcohol, phenylacetic acid,
and 4-hydroxyphenylacetic acid.
Turning to practical applications of pesticide photolysis, the most im-
portant recent example, and perhaps the only one, is the environmental degra-
dation of 2,3,7,8-tetrachlorodibenzo-£-dioxin (TCDD) as reported by Crosby and
Wong (1977) and Crosby (1977). These papers incorporate and build upon the
previous work of other researchers. It is known that thin films of pure TCDD
on glass substrates are stable to sunlight for at least 14 days. However, the
same material dissolved in organic solvents (or 15 ppm TCDD in Herbicide Orange)
rapidly decomposed with a half-life of approximately 6 hr when exposed to sun-
light. Further work established that the loss of TCDD was caused by photolysis,
not volatilization, absorption, or mechanical loss.
90
-------
M-N
'/
SENSITIZtR N, • NH,C = N
H, H,0
Amitrole (3-amino-f-triazolel
Ring fission (Plimmer Cl al., 1967)
•"*
Cl
SENSITIZED
Cl
Cl
ci
3,4-Oichloroaniline
C'ondenution (Rosen ft al.,' 1970; Ptimmcr and Kearney, 1969)
Cl Cl
DIELDRIM
Cl Cl PHOTODIELDRIN
[ l.2.3.4,10.lO-he»achloro-6,7-epo»v-l .4.4a,S.6,7,8,8a-oclahydro-1.4y-3.S-diiodobenionitrile)
Replacement ol halopcn by phenyl ll'gochukwu jnd Wain. 1965)
Sources Plimmer (1972 )0
Figure 19. Examples of pesticide photolytic reactions.
91
-------
The mechanism for photolysis of TGDD is currently believed to take place
as follows:
* Absorption of UV light
* Photosensitization of the TCDD by a hydrogen-donor solvent
* Homolytic cleavage of a G-Cl bond
* Formation of a C-H bond in which hydrogen abstraction from the donor
solvent occurs
Intermediate photolytic products include tri-, di-, and monochlorinated species.
The final product of TCCD photolysis is dibenzo-p_-dioxins which is capable of
being further decomposed.
LIQUID PHASE DISPOSAL METHODS
Several detoxification methods carried out in the liquid phase are discussed
in this subsection, in the following order:
* Activated carbon and resin adsorption
* Hydrolysis and simple chemical treatment
* Molten salt bath procedures
* Ozonation procedures
* Wet air oxidation
Molten salt bath procedures are included in the discussion of liquid phase
detoxification methods rather than in Section 4, Incineration Methods, because
all or part of the degradation process takes place in a molten phase rather
than in a gas phase as with the more traditional combustion units. Further,
the usual combustion operating parameters for incinerators, e0go, dwell (resi=
dence) time, excess oxygen, fuel feed rate, degree of turbulence, etc<>, are
either not meaningful or are unimportant characteristics of molten salt baths.
Activated Carbon and Resin Adsorption Processes
In general, adsorption processes have been utilized for removal of organic
and inorganic materials from dilute wastewater, i.e., solutions in which the
concentrations of the constituents to be removed are < 0.1% by weight» For ex-
ample, a manufacturer of 2,4-D, MCPA, and 2,4-DB used activated carbon to treat
a 600,000 liter/day (150,000-gal/day) waste stream that contained 10 ppm phenol
92
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and cresol and 100 ppm chlorophenols and chlorocresols. After treatment, the
combined phenolics remaining in the wastewater were < 1 ppm (Rizzo, 1972).
The EPA Demonstration Project at Velsicol Chemical Corporation, Memphis,
Tennessee* may be cited as an example of resin adsorption of pesticides. Waste-
waters with endrin, heptachlor, and related compounds present at ^ 1 ppm are
being treated to reduce the concentration to ^ 1 ppb in the effluent stream.
Isopropanol is used to regenerate the resin (Rohm and Haas Company, Amberlite
XAD-4) and is recovered by distillation. Endrin and related chemicals are con-
centrated as still bottom materials which are ultimately incinerated. Reports
on progress of this project are available from EPA-Industrial Environmental
Research Laboratory, Research Triangle Park, North Carolina (Marx, 1977).
Activated carbon or resin adsorption has not been applied to concentrated
waste streams or used to recover the AI from a typical (1 Ib/gal) emulsifiable
concentrate of herbicide. In this case, not only would the AI be adsorbed by
the carbon bed or column, but other ingredients, including emulsifiers, dilu-
ents, synergists, and inorganics, would be adsorbed as well. The adsorption
'powers of the activated carbon would be rapidly depleted, thus requiring re-
generation. Attempts to reclaim the AI during regeneration of the carbon by
'solvent extraction or by treatment with acid or alkali are hindered by the
tendency for. all the adsorbed species to be released from the carbon. In using
adsorbent resins to reclaim pesticide AI from formulations, similar problems
are encountered. Thus, recovery of the pure AI is generally not practical for
formulation. Activated carbon or resin adsorption is more useful to concentrate,
isolate, or control organic materials at the point of discharge from a reactor
or processing unit at the manufacturing facility than for solving field dis-
posal problems (Rizzo, 1977).
Hydrolysis and Other Simple Chemical Treatment Processes
Many chemical approaches have been taken to detoxify or destroy hazard-
ous materials, including pesticides. These approaches generally involve rather
simple treatments in solution, e.g., application of heat, pressure, alkali,
chlorine, hypochlorite, etc. Some of these methods are capable of completely
destroying specific pesticides, e.g., alkaline hydrolysis of organophosphorus
compounds. Others only partially detoxify the AI or can yield products which
are just as toxic as or even more toxic than the original pesticide. We shall
examine key examples of these processes and indicate their general usefulness,
inherent shortcomings, and current status. The order of discussion of various
pesticide disposal research by chemical treatment is chronological.
Chemical treatment of pesticides has been investigated at the Mississippi
Agricultural Experiment Station, Mississippi State University (Kennedy et al.,
1969). The pesticides selected for study, listed in Table 8, were 12 readily
available commercial formulations.
93
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TABLE 8. CHEMICAL DEGRADATION RESULTS FOR SELECTED PESTICIDES
V£>
Concentrations
Reagents employed
H202 5%, 15%, 307o
HN03 4N, 8N, 16N
H2S04 9N, 18N, 36N
NaOH 2N, 4N, 8N
NfyOH 5N, 7.5N, 15N
Listing of
all pesticides
tested
Atrazine
Bromacil
Carbaryl
2,4-D
Dicainba
Dieldrin
Diuron
DNBP
Malathion
Nemagon® (DBCP)
Pic lo ram
Trif luralin
Results
Pesticide, reagent Chemical change
All pesticides,
H202
Carbaryl, HN03
Atrazine, HN03
Bromacil, H2S04
Dieldrin, NaOH
Malathion, NaOH
Dicamba, NaOH
2,4-D, NaOH
DNBP, NaOH
Picloram, NaOH
Bromacil, NaOH
Carbaryl, NH^H
Trifluralin, NH40H
No significant effects on all
pesticides tested
Nitrobenzene formed
2-Hydroxy-s-triazine formed
Unspecified structural change
Unspecified structural change
Inorganic phosphate formed
No significant effects
Sodium salt of 2,4-D formed
Unspecified structural change
Decarboxylated and chlorine
group replaced by hydroxyl
group
Unspecified structural change
1-Naphthol formed
Minor color change
Source: Kennedy et al. (1969).
-------
The objective of the study was either to degrade partially or to decom-
pose completely the AI under controlled chemical conditions. Analytical methods
included thin-layer chromatography (TLC) and infrared analysis (IR).
Formulations of pesticides in benzene solution were reacted with an excess
of an appropriate chemical reagent, listed in Table 8, at various concentra-
tions in a 1:5 (v/v) ratio at room temperature for 24 to 36 hr with occasional
vigorous shaking. The solvent layer was drawn off, evaporated to approximately
1.0 ml, and analyzed by TLG or IR. The aqueous layer was extracted three times
with either a chloroform-benzene mixture or ri-hexane, and then the hydrocarbon
layer was analyzed by IR. Results of these experiments are given in Table 8.
According to Kennedy et al. (1969), eight of the pesticide compounds were
partially decomposed when treated with strong acid or alkali; three pesticides
appeared unaffected. In general, acid or alkaline hydrolysis under specified
experimental conditions was incomplete for the pesticides chosen for study.
The probability of finding a simple, universal chemical reagent to destroy
or degrade many classes of pesticides appears to be very small. Based on the
evidence obtained from their chemical degradation studies and also from thermal
decomposition studies which were performed at the Mississippi Agricultural Ex-
periment Station (including differential thermal analysis, dry combustion,
and ashing techniques in a muffle furnace), Kennedy et al., concluded that in-
cineration is superior to chemical treatments as a general method for the de-
struction of waste pesticides (Kennedy et al., 1969).
In a related study, Kennedy and his co-workers treated four organophos-
phorus insecticides (DDVP, parathion, schradan, and Systox®) with approxi-
mately 100 chemical reagents (Kennedy et al., 1970). The individual reagents
are not listed heres but they included organic and inorganic acids, organic
and inorganic bases, amines, amides, organic peroxides, enzymes, household
detergents, various bleaches, solvents, phenols, chelating agents, metallic
ions, organic and inorganic salts, heterocyclic compounds, sodium and lithium-
metals in liquid ammonia, amino acids, etc.
The principal results of this screening and testing program are given in
Table 9, in which those combinations are listed for which degradation was at
least 90% complete. Other reagents, e.g., phosphatase enzymes and enzyme active
household detergents, produced only partial decomposition of parathion.
Hydriodic acid produced partial decomposition of DDVP, parathion, and Systox®.
Benzoyl peroxide and £-butyl peroxide destroyed approximately one-half of all
four insecticides tested. £-Toluene sulfonic acid partially decomposed schradan.
95
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TABLE 9. SUCCESSFUL CHEMICAL DEGRADATION OF FOUR
ORGANOPHOSPHORUS INSECTICIDES
Percentage
Insecticides Reagent employed decontaminated
DDVP, parathion, schradan, Metallic sodium in 100
Systox® liquid ammonia 100
DDVP, Systox
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TABLE 10. HALF-LIVES OF VARIOUS PESTICIDES UNDER ALKALINE CONDITIONS
Pesticide
Para th ion
Methyl parathion
Malathion
DDVP
Diazinon®
Carbaryl
Propoxur (Baygon®)
Experimental
conditions
Temperature
15 °C
15°C
25 °C
37.5°C
20 °C
Ambient
20°C
PH
1 N NaOH
1 N NaOH
10.03
8.0
10.4
Alkaline
10.0
Half-life
32 min
7.5 min
28 min
462 min
144 hr
Rapid
40 min
Source: Dennis (1972).
TRW Systems, Inc. (Ottinger et al., 1973), has studied methods of reduc-
tion, neutralization, recovery, or disposal of hazardous wastes, including
pesticides. These authors review alternate disposal options for dilute and con-
centrated pesticide wastes and ultimately select and recommend optimum proce-
dures (see Volume V of Ottinger et al.). Classes of pesticides discussed in-
clude: chlorinated hydrocarbons, organophosphorus, and diene-based compounds.
Table 11 summarizes the options and final recommendations of the study, which
are coded as follows:
No. 1 - Adsorption with powdered activated carbon
No. 2 - Adsorption with granular activated carbon beds
No. 3 - Coagulation and filtration
No. 4 - Acid hydrolysis
No. 5 - Alkaline hydrolysis
No. 6 - Chemical oxidation
No. 7 - Chemical reduction
No. 8 - Anaerobic degradation
97
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TABLE 11. SUMMARY OF TRW ALTERNATE OPTIONS FOR DISPOSAL OF PESTICIDE WASTES*/
Pesticide
solution strength
Alternate disposal options
(coded)
Disposal options—
in order of preference
vo
00
Chlorinated hydrocarbons
DDT, ODD, BHC
Dilute pesticide wastes
Concentrated pesticide wastes
Organophosphorus compounds
Methyl parathion, parathion
Guthion®, Systox®
Dilute pesticide wastes
Concentrated pesticide wastes
Diene-based compounds
Chlordane, aldrin, endrin
Heptachlor, dieldrin
Dilute pesticide wastes
Concentrated pesticide wastes
1, 2, 3, 5, 8, 9
7, 11, 12, 13
1, 2, 5, 9, 10
5, 7, 11, 12, 13
1, 2, A, 6, 8, 9
7, 11, 12, 13
2-Activeted carbon beds
5-Alkaline hydrolysis
13-Incineration
2-Activated carbon beds
10-Activated sludge treatment
5-Alkaline hydrolysis
13-Incineration
2-Activated carbon beds
13-Incineration
Source: Ottinger et al» (1973)°
a/ These methods may not be in accordance with current regulations and guidelines established under Federal
~ Insecticide, Fungicides and Rodenticide Act (FIFRA) and Resource Conservation and Recovery Act (RCRA)o
-------
9 = Removal by surface active agents
10 « Activated sludge treatment
No0 11 = Deep well injection
NOO 12 - Sanitary landfill
No« 13 - Incineration
Although many alternate disposal options are potentially available and
some preliminary development work has been accomplished for each technique,
Ottinger and his co-workers recommend only a very limited number of options
for disposal of dilute and concentrated pesticide wastes. For dilute wastes,
activated carbon beds are commonly selected. This choice is based on demon-
strated and well-established chemical engineering technology and dates back
to at least 1955 in England (Lambden and Sharp, 1970; Sharp, 1956). Incinera-
tion is the only recommended option for concentrated pesticide wastes.
The TRW report rejects deep-well injection and sanitary landfill as not
representing practical, safes long-term disposal options (in conformity to
the present position of EPA). Other options including chemical treatment were
considered to be inadequate for the job or too narrow of utility to be of
general application*
Another hydrolytic technique for detoxification of organophosphorus pes-
ticides has been developed by Wolverton (1973). Specifically, the procedure
involves forming a solution of monoethanolamine (MEA) in dipropyleneglycol mono-
methyl ether (DPGME) and applying it to an organophosphorus pesticide spill.
The specific application cited in the UoS. Department of the Interior patent
is for cleanup of spills associated with aircraft spraying operations.
Wolverton1s work was a part of the technical support required for the chemical
warfare program of the Department of the Air Force in the late 1960's and early
1970°So Organophosphorus pesticides that were susceptible to detoxification
included: malathion, naled, dibrora, TEPP, and DDVP. No other pesticides were
mentioned in the patent.
The decontamination procedure involved treating one volume of pesticide
with 10 volumes of the decontaminating mixture containing 12.5 to 25% MEA in
DPGMEa Reaction times varied from 30 to 100 min at ambient temperatures for
a complete reaction, depending on the individual pesticide. The completeness
of degradation of the AI was confirmed by thin-layer chromatography.
Based on these data, Wolverton claimed the resulting reaction mixtures
were less toxic to fish than was the decontaminating solution alone. Further,
"The resulting mixture of decontaminant and insecticide can be readily hosed
99
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away with water without having the resulting runoff deleteriously affecting
any nearby streams and fishlife therein" (Wolverton, 1973). The reaction mix-
ture is noncorrosive toward the aluminum metal alloys commonly used in aircraft
construction*
If these claims are valid, this procedure may offer a reasonably simple,
relatively inexpensive, and environmentally sound method to clean up spills
of organophosphorus pesticides resulting from aircraft spraying operations,
drum or container rinsing and reclamation operations, pesticide waste disposal
problems, and other accidental spills.
Wolverton was contacted at the National Space Technology Laboratory,
Bay St. Louis, Mississippi, and asked to review his previous work and to assess
the application of this technology (Wolverton, 1977). He orally reconfirmed
his earlier findings and continues to stand behind the conclusions stated in
the patent. To his knowledge, no one in the public or private sector is uti-
lizing his findings.
An MRI report presented disposal suggestions for small quantities (< 50
Ib or < 5 gal.) of unused pesticides (Lawless et al., 1975). A total of 550
chemicals that have been sold as pesticides were identified and classified
into seven major categories according to structure and reactivity; and infor-
mation on each was compiled from technical literature on their pesticidal uses
and properties, and their detoxification and degradation chemistries. Fourteen
disposal procedures were described suitable for the layperson with guidance
from a responsible official. Separate procedures describe the proper disposal
of containers and the cleanup and treatment of spills* Table 12 summarizes the
findings.
A TRW Systems Group study produced a Handbook for Pesticide Disposal by
Common Chemical Methods (Shih and Dal Porto, 1975). One objective of the project
was to assess simple chemical degradation/detoxification methods for the dis-
posal of small quantities of pesticide wastes. A second goal was to advise pes-
ticide users of safe, reliable methods for pesticide disposal, including as-
sociated hazards of disposal of which the layperson should be aware. This study
represents a literature review; field testing of the recommended chemical
procedures was not performed.
A total of 20 pesticides chosen from three major categories or chemical
families were investigated in terms of production volume, toxicity, soil per-
sistence, mobility, and solubility in water. Identification of practical chemi-
cal degradation/detoxification methods for pesticide disposal was determined
by literature review and contact with manufacturers.
The study concluded that treatment by alkali is an effective and environ-
mentally sound method for the disposal of small quantities of certain pesticides,
but it was emphasized that this method is by no means a universal one. This
100
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TABLE 12. SUMMARY OF MRI DISPOSAL PROCEDURES AND ELIGIBLE PESTICIDES*/
NOc
Procedure
Eligible pesticides
(%) primary
recommendation
Pesticide examples
la Turn in to pesticide
collection center
20 Return to supplier
3o Turn in to industrial
waste service
49 Place in trash for
pickup service
50 Incineration
6e Open'burning
7, Treatment with alkali
Bo Treatment with acid
9e Treatment with oxi-
dants
10o Treatment with reduc
tants
11o Burial in the ground
28.2
3.6
2906
1.7
10.4
2.4
1.0
0.0
18.7
(continued)
Aldicarb, mercury compounds
Parathion, Compound 1080
Dieldrin, nicotine, TEPP,
thallium sulfate
Butoxy polypropylene glycol,
chlorinated hydrocarbons
as liquids* Dyrene®,
atraton, barban
DDT, 2,4,5-T and other highly
chlorinated hydrocarbons
No longer recommended as a
general disposal method
Acephate, Aramite®, bromo-
phos, butonate, carba-
mates, BUX TEN®, captan,
carbaryl
Nabam, CDEC, Dithane® M-45,
M-31, ferbam, maneb
Thanite®, Folex®, calcium
cyanamide, calcium cyanide
Acrolein, formaldehyde,
sodium chlorate (alternate
procedures)
Arsenicals, organoraetallics
(other than mercury com-
pounds), sulfur, creosote,
oils
101
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TABLE 12 (CONTINUED)
No.
Procedure
Eligible pesticides
(%) primary
recommendation
Pesticide examples
12. Ground surface dis-
posal
13. Dilution
14. Release to air
1.7
2.0
0.7
Liquid fumigants, CCl^, di-
n^butylphthalate,
Tropital®
Botanicals, butoxy poly-
propylene glycol, n-
decanol, magnesium chlo-
rate, propionic acid
Aerosol formulations,
pyrethrins, methyl bro-
mide, ethylene, propylene
oxide
Source: Lawless et al. (1975).
a/ These methods may not be in accordance with current regulations and guide-
"~ lines established under Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA) and Resource Conservation and Recovery Act (RCRA).
102
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conclusion was reached after consideration of completeness of the reactions
and toxicity of the final products. Table 13, taken from the TRW report, in-
dicates those pesticides which may be safely disposed of by laypersons using
simple alkaline treatment and those pesticides for which chemical treatment
is inadvisable. The pesticide classification system is taken from a report by
Lawless et al. (1975) and indicates the TRW report focuses on three major
categories.
Table 13 indicates that certain pesticides may not be disposed safely by
alkaline hydrolysis, whereas other pesticides within the same class may be so
disposed. This is an important point, since disastrous results might occur if
one assumed that all pesticides in a given class could be safely disposed
merely because one pesticide in that class was listed as being safely detoxi-
fied by alkaline treatment.
The TRW report offers recommended procedures for the disposal of small
quantities of pesticides and decontamination of pesticide containers. Details
include pesticide AI, formulation, decontaminant solution, ratio of decontami-
n'ant solution to formulation, and contact time. For example, atrazine as a wet-
table powder (WP) may be detoxified by treatment with a 10% (w/v) solution of
NaOH. The TRW report directs the layperson to treat 1 Ib of atrazine WP with
1 gal. of caustic for 48 hr.
The TRW report also offers alternate disposal methods for 13 pesticides.
These methods include land burial, land burial with acid treatment, and ground
surface disposal. Incineration is another alternative, but the necessary equip-
ment is not generally available to the layperson; hence, the emphasis on the
three alternative methods discussed above.
The TRW report recommended the National Agricultural Chemicals Association
(NACA) "triple rinse and drain" procedure for the decontamination of glass and
metal pesticide containers. The rinse water from treatment of pesticides that
are not decomposed by caustic must be properly disposed of by incineration,
burial at an approved landfill, or burial in an isolated area where it is ex-
tremely unlikely that the pesticide will enter groundwater supplies (Class 1
site).
Combustible pesticide containers which previously did not contain toxic
metals are best handled in approved incinerators. Alternately, the containers
may be buried in an approved landfill. Small aerosol cans for pesticides are
not to be incinerated or punctured. These are more properly disposed by munici-
pal trash service, which is primarily directed to sanitary landfill operations.
Further discussion of recommended procedures for disposal and storage of pes-
ticides and pesticide containers is given in Appendix B.
103
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TABLE 13. CHEMICAL METHODS FOR DISPOSAL OF SELECTED PESTICIDES
Class of pesticide
Pesticides evaluated
Recommend use of
alkali
Recommend no chemical
treatment
Inorganic and metal-organic
pesticides
Phosphorus-containing
pesticides
Nitrogen-containing
pesticides
No examples given No examples given
Halogen-containing
pesticides
Sulfur-containing
pesticides
Diazinon®
Guthion®
Malathion
Naled
Atrazine
Captan
Carbaryl
Dursban®
Methyl parathion
Alachlor (Lasso®)
Diuron
Maneb
Picloram
Trifluralin
No examples given Amiben®
Chlordane
2,4-D
Methoxychlor
Pentachlorophenol
Toxaphene
No examples given No examples given
Botanical and microbiological No examples given No examples given
pesticides
Organic pesticides, not
elsewhere classified
No examples given No examples given
PRECAUTIONS; Use personal protection equipment^. Follow disposal procedure
closely. Dispose larger quantities in several smaller
batches.
Source: Adapted from Shih and Dal Porto (1975).
104
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Current projects at the U.S. Army Medical Bioengineering Research and
Development Laboratory at Fort Detrick, Frederick, Maryland, include hydro-
lysis of Diazinon®, malathion, Dursban®, and naled. Meier et al. (1976) have
published an in-depth study of the hydrochloric acid catalyzed hydrolysis of
Diazinon®* The research included the pure AI and three military standard formu-
lations, 47.5% emulsifiable concentrate, 2% dust, and a 0.5% oil solution. The
detailed studies attempted to optimize the reaction conditions, to determine
the rate of reaction, to identify mechanisms and products of the reaction,
and to evaluate the toxicity and environmental affect of the final reaction
mixture. This work constitutes one of the more complete investigations of
chemical treatment of a specific pesticide since it deals with the overall
field disposal problem.
Conclusions reached by the Department of the Army group were:
* Hydrolysis by HC1 (1.1 N) degrades Diazinon®with a half-life of 215
min at 25°C
| * Total reaction time for 99.9% decomposition at 25°C varies from 28 to
42 hr depending on the specific pesticide formulation, including the
pure AI
* Neither of the principal decomposition products of the reaction was
found to be toxic to aquatic species of waterflea, bluegill fish, and
rainbow trout
* Additional aquatic bioassay data indicate that the final reaction
mixture possesses a residual toxicity of unknown character toward
aquatic species
Work is continuing on this topic to identify and eliminate the cause of
the residual toxicity. At present the technology is not considered by the
Department of the Army to be a safe disposal method for Diazinon®.
Molten Salt Processes
Atomics International Division of Rockwell International Corporation has
spent considerable time and effort over the last 20 years to develop expertise
in molten salt technology. Recently, this body of knowledge has been directed
toward solid waste disposal, particularly industrial and hazardous wastes.
The molten salt bath has inherent advantages over conventional combus-
tion techniques in that: (a) excellent thermal contact is maintained be-
tween the heat source and the carbonaceous waste material; and (b) the re-
sulting off-gases generally do not contain acidic components (e.g., oxides of
sulfur) because of the caustic salt used (e.g., usually sodium carbonate or
a eutectic mixture of sodium and potassium carbonates). Further, the salt bath
105
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is stable, nonvolatile, relatively inexpensive, n on toxic, and may be recycled
for further use*
The process is applicable to a host of waste disposal problems, including:
* Pesticides and combustible pesticide containers
*. Combustible industrial and consumer wastes
* Hazardous chemicals, including carcinogens
* Explosives
* X-ray film
* Hospital wastes
* Low level radioactive wastes
The principal steps of the operation are as follows*
The combustible waste material is shredded in a hammer mill and conveyed
to a hopper to await entry into the bath, a large vessel, 3*1 m (10 ft) high
and 0.9 m (3 ft) diameter, that contains the molten salt which is maintained
between 800 to 1000°C. The waste material is blown into the reactor by an air
stream which also furnishes oxygen for the combustion process* The bath is
preheated on startup; once the reactor is in operation, the heat of combustion
makes the process self-supporting. In the current pilot-scale model, feed
rates may be varied from 23 to 91 kg/hr (50 to 200 Ib/hr) depending on the ap-
plication. Figure 20 indicates the general molten salt combustion process con-
cept, and Figure 21 indicates a schematic flow diagram for a pilot plant
facility.
In the reactor vessel the essential or overall chemical reaction is
summarized below:
Carbonaceous material, con- ^
taining C, H, 0, N, S, Cl, P, + Oo — ,—-—7—, • ' ' • , • >
i molten salt bath with iron catalyst
etc. '
Off-gases, including CO-, H20, N2» 02, and converted wastes as sulfatesf phos-
phates, chlorides
Off-gases are sent through a baffle assembly to trap and remove entrained
salt particles and then to a high energy venturi scrubber unit to remove any
fine particulate matter before emission to the atmosphere* Acidic scrubber
units are not needed since these components are absorbed by the alkaline car-
bonate melt*
106
-------
STACK
o
-J
OFF-GAS
CLEANUP
, H20, N2, 02
A1F
WASTE
WASTE
TREATMENT
AND FEED
. 1 WASTE AND AIR .
1 i
; MOLTEN SALT
3 FURNACE
^^nn^^
SALT RECYCLE
4 , g
t
I
»
! SPENT MELT
*! REPROCESSING
• OPTION
SPENT MELT
DISPOSAL
< •
Source: Atomics International (1975).
ASH
Figure 20. Schematic of molten salt combustion process.
-------
O
00
1
MOLTEN SALT
COMBUSTION
FURNACE
MELT AND ASH
TO DISPOSAL
Source: Atomics International (1975).
Figure 21. Schematic of the molten salt pilot plant.
-------
In time, the molten salt bath accumulates significant quantities of sodium
chloride, phosphate, sulfate, other noncombustible material, etc*, that affect
the fluidity of the melt. The inorganic "ash" must be removed when the combined
total of all dissolved impurities reaches 20% by weight.
The "spent" molten carbonate is recycled by transferring it to a dissolving
tank where it is treated with water or aqueous sodium bicarbonate solution; the
dissolved carbonate solution is filtered to remove insoluble materials and
treated with carbon dioxide gas to precipitate sodium bicarbonate. The bicar-
bonate salt is recovered by filtration and used in the molten salt furnace
where it is reconverted to carbonate. The remaining bicarbonate solution is
normally recycled, but eventually it accumulates too much chloride, phosphate,
and sulfate and must be discarded. Figure 22 indicates a scheme for recycling
carbonate melt as described above (Birk, 1973).
Table 14 indicates four classes of hazardous chemicals and wastes tested
thus far by Atomics International, i.e., pesticides, industrial chemicals, low
level radioactive wastes, and explosives. Of interest to this study are the
pesticides tested and the degree of decomposition achieved by molten salt bath
technology* As indicated in Table 14, the pesticides tested represented several
classes of chemicals: the chlorinated hydrocarbons, DDT, 2,4-D, and chlordane;
the organophosphorus compound, malathion; and the carbamate, Sevin®, were
tested as the pure AI contained in polyethylene bags; a malathion-DDT mixture
was tested in xylene solution. These experiments were performed utilizing a
bench-scale reactor at 825 to 925°C with efficiencies of the order of 99.9+%.
Estimated process rates were 0.5 kg/hr (1 Ib/hr) (Yosim, et al., 1974).
Gaseous emissions were monitored, and essentially only C02, CO, t^O, 0£>
and N2 were found in the exhaust gas. Small amounts of nitric oxides (< 20 ppm),
organic chlorine (< 0.04% of the original pesticide) and traces of hydrocarbons
(< 10 ppm) were found.
Tables 15 and 16 present summaries of results for molten salt bath com-
bustion of various pesticides and other hazardous chemicals* Temperature
ranges, percentage chemical or pesticide destruction, and concentration of the
material in the exhaust gas are given. It is evident that, on the bench-scale
level of operation, very high combustion efficiencies can be obtained, > 99.99%.
Thus, destruction of pesticides and other hazardous chemicals by molten salt
bath technology has been demonstrated on the bench scale at 0.25 to 1.0 kg/hr
(1/2 to 2 Ib/hr) and scale-up to 450 kg/hr (1,000 Ib/hr) for these materials
has been suggested (Atomics International, 1975).
Atomics International has proposed a preliminary design for a large mobile
molten salt disposal system, as shown in Figure 23.
109
-------
Carbonaceous
Material
(e.g. Coal
or Fuel Oil)
Air
r
~l
I
Carbon Dioxide
Nitrogen
L_-».
Furnace
Molten Salt
(e.g. Na2CO3)
Containing Sulfide
Aqueous
Solution
NaHCOa
Hydrogen Sulfide
Carbon Dioxide
NaHCOo
(Solid)
Source: Birk (1973).
Figure 22. Schematic flow diagram for recycling carbonate melt.
110
-------
TABLE 14. HAZARDOUS CHEMICALS AND WASTES TREATED
BY MOLTEN SALT BATH
Type of chemical or waste
Materials tested
Pesticides
Industrial chemicals
DDT powder, malathion, DDT-malathion solu-
tion, chlordane, 2,4-D, and carbaryl
Chloroform, trichloroethane, nitroethane,
nitropropane, diphenylamine hydrochloride,
monoethanolamine, diethanolamine, and para-
arsanilic acid
Low level radioactive
wastes
Explosives
Polyvinylchloride, polyethylene, rubber,
paper, ion exchange resins, tributyl
phosphate solvent, etc., contaminated
with transuranic and/or fission products
Composition B, TNT, tetryl, HBX-3, ammo-
nium nitrate, glyceryl nitrate,
cyclonite, and TNG
Sources Yosim et al. (1974).
Ill
-------
TABLE 15 / SUMMARY OF RESULTS OF MOLTEN SALT BATH
COMBUSTION TESTS ON CHEMICALS
Concentr at ion
Chemical
Chloroform
Diphenylamine HC1
Nitroethane
Para-arsarilic acid
Average
test
temperature
818
922
892
924
Percent of
chemical
destroyed
> 99.999
> 99.9992
> 99.993
> 99.9991
of
chemical
in melt
(ppm)
< 0.1
< 0.1
< 1
< 0.15/
Quantity
in gas
(Mg/m3)
< 0.5
< 0.4
< 4.4
< 0.8
TLV
120
10£/
310
0.5l/
Source: Atomics International (1975).
a/ While the concentration of £-arsanilic acid in the melt is extremely low, the
concentration of inorganic arsenic compounds in the melt is, as expected, high,
since the arsenic is retained in the melt as sodium arsenate.
b/ Threshold limit value* American Conference of Governmental Industrial Hygienists,
Cincinnati, Ohio, 1976.
£/ As diphenylamine.
d/ As arsenic.
-------
TABLE 16. TYPICAL RESULTS OF MOLTEN SALT BATH COMBUSTION TESTS
ON PESTICIDES
Pesticide
DDT powder
Malathion
DDT -ma lathi on
solution
DDT
Malathion
Average
test Percent
temperature pesticide
( °C) destroyed
894 99.998
896 99.999
992
99.997
99.996
Concentration
of
pesticide
in melt
(ppm)
< 0.2
< 0.005
< 0.05
< 0.01
Concentration
in exhaust
gas
(Mg/m3)
0.34
0.42
1.4
1.1
TLV2/ of
pesticide
(Mg/m3)
1
10
1
10
Source: Atomics International (1975).
a/ Threshold limit value. American Conference of Governmental Industrial Hygienists,
Cincinnati, Ohio, 1976.
-------
VIEWPORT
SALT FEED
SYSTEM
ALT. FEED
SYSTEM
VESSEL
PREHEATER
SHREDDER
ROTARY VALVE
RAIN CART
STACK
'ARTICLE
COLLECTOR
CONVEYOR
Source: Atomics International (1975).
Figure 23. Mobile molten salt waste disposal system.
-------
The combustor and auxiliary components are mounted on a truck bed which would
allow the system to be moved from site to site for destruction of large quanti-
ties of hazardous materials. This would be a definite advantage since trans-
shipment of pesticides and other hazardous chemicals across state lines for
disposal is a sensitive issue in many parts of the country. Secondly, the com-
bustion unit could be more widely utilized because of its mobility.
The Atomics International mobile combustion unit would be capable of proc-
essing 230 kg/hr (500 Ib/hr) or an estimated 2.76 Ml/day (3 tons/day) based
on 12 hr/day operation. The combustor would be 1«8 m (6 ft) diameter and 3.35
m (11 ft) tall. For solid pesticides a mechanical screw conveyer would auto-
matically feed the combustor at a predetermined rate. For liquid pesticides,
metering flow rate devices are available. The exhaust gas is passed through
a particulate scrubber and/or separator to remove entrained salt particles
and may be passed through a baghouse (not shown) before it is emitted.
Chemical monitoring of the exhaust gas to determine operating efficiency
and absolute quantities of undestroyed pesticide released to the environment
5is recommended. Records would be kept as to type of pesticide incinerated,
'including Al, formulation, time of burns length of burn, temperature, absolute
.quantity incinerated, exhaust gas analysis, total amount released to the environ-
ment, atmospheric conditions, etc.
Contaminated carbonate salt could be automatically reprocessed by appro-
priate apparatus on a second truck bed (not shown), or the spent molten salt
could be released to a drain cart and buried in a Class 1 disposal site.
A second type of molten salt incineration is under development by Anti-
Pollution Systems, Ince (APS)e The incinerator has been designed principally
for municipal garbage and sewage, although there are many other potential ap-
plications, including chemical wastes and pesticides. A recent application was
to mount the unit on a truck bed (which allowed the equipment to be transported
from New Jersey to Maine, where the system incinerated tannery wastes and per-
mitted recovery of chromium metal values) (Greenberg, 1977).
Figure 24 presents a schematic diagram of one configuration of the APS
system. Solid waste is introduced through an auxiliary mechanical feed com-
ponent (not shown); or, if the waste is a liquid, e.g., a pesticide formula-
tion, it may be mixed with the fuel oil prior to incineration. The combustion
unit is essentially a box within a box and in contact with a molten salt bath.
After ignition of the fuel (oil or gas), the waste material begins to com-
bust and transfers the heat generated to the salt bed beneath the combustion
chamber. The molten salt maintains the bottom portion of the combustion chamber
at the melting point of the salt. If the heat of combustion is great enough and
a sufficient quantity of waste is burned, it is not necessary to premelt the
salt bed.
115
-------
Exhaust
Blower
Modified
Cyclone
By-Pass Valve
Oil or Gas
Intake
A
Molten Salt
APS, Inc. Molten Salt Incinerator
Source: Adapted from APS, Inc.
(undated).
Figure 24. APS molten salt incinerator.
116
-------
Once the combustion process is started, the exhaust gases which are pro-
duced enter the molten salt bath via a series of baffles. The temperature of
the molten salt is approximately 560 to 600°C (1042 to 1112°F), lower than the
800 to 1000°c (1472 to 1832°F) used in the Atomics International unit. A modi-
fied dry cyclone collector prevents salt losses at air velocities above 400
ft/mih. The estimated residence time for off-gases in the molten salt is ~0.1
sec at 560 to 600°C, which has been shown to be sufficient for odor removal
and oxidation of organic vapors for sewage sludge and pathological wastes.
The molten salt bath performs three functions in treating or processing
the off-gases:
1. Particulates are trapped with the salt bath.
2* The salt bath operates as an afterburner.
3« Toxic volatiles may react further with the molten salt*
Impurities trapped in the salt bath (carbon particles and inert materials) may
be removed by use of a fine mesh stainless steel screen. Combustible carbon
particles would eventually be oxidized to CO2 by the use of steam.
No pesticides or pesticidal formulations have been incinerated in the
APS, Inc. device at the time of writing, although chlorinated hydrocarbon wastes
have been treated. No operating data, e.g., efficiency of destruction, descrip-
tion of the off-gases, material balance, flow rate, etc., are available, how-
ever.
Ozonation Methods
We shall describe three pesticide detoxification methods utilizing ozone
gas. These are:
* Ozone/ultraviolet irradiation
* Sonocatalysis, and its simpler version
* Catalytic ozonation
Each is described below.
Ozone/Ultraviolet Irradiation--
Houston Research, Inc., has developed a method of destroying or detoxify-
ing hazardous chemicals in solution, including heavy metal cyanides and pesti-
cides, utilizing a combination of ozonation and UV irradiation. The technique
involves rather simple apparatus: a reactor vessel, an ozone generator, a gas
diffuser or sparger, a mixer, and a high pressure mercury vapor lamp. Pesticides
117
-------
that have been reduced to levels of < 0.5 ppra from an initial solution concen-
tration of —50 ppm include: PGP, malathion, Vapam® and Baygon®. DDT has been
reduced from 58 ppb in solution to < 0.5 ppb in 90 min (Mauk et al., 1976).
The principle of operation is as follows: the hazardous material in
aqueous solution is placed in a plastic or steel reactor which is fitted with
a gas diffuser or sparger at the bottom. Inside the reactor is a temperature
sensing/controller device, an electrode for monitoring pH changes and a mixer
or impeller. A high pressure mercury lamp contained in a quartz housing is
placed in the solution. Ozone is generated by electrical discharge, and excess
ozone may be vented to the atmosphere through a potassium iodide solution trap.
Two reactors, 10- and 21-liter volumes, have been tested to date (both
considered to be bench-scale models). Houston Research, Inc., indicates, how-
ever, that scale-up to much larger sizes should be feasible. Figure 25 presents
a schematic diagram of the bench-scale apparatus.
The overall chemical reactions that occur depend on the specific pesti-
cide being detoxified; in general, the process involves activation of the
organic molecule to a highly energetic state by UV illumination, followed by
vigorous attack by ozone:
UV
Pesticide -f- 03 '> C02 + H20 + Other simple species
The actual mechanism is much more complicated than this simple reaction scheme
indicates. Thus, pentachlorophenol may be initially dehalogenated followed by
ring oxidation:
OH
_+. 2C02 + H20 + 02
In the case of malathion at least four separate mechanisms are possible
involving portions of the parent molecule. These are given in Figure 26. The
overall reaction is:
C10H19S2P06 + 6403'
19H20 + 20C02 + 4503 + P205 + 6402
118
-------
Mixer
UV Light
Sparged
Batch
Reactor
I 1
Impeller
i 1 1 I I
Ozone
Generator
Exhaust Gas
Temperature
Control
pH Monitoring
and Sampling
2% Kl
Solution
Vent
Power
Oxygen or Air
Source: Adapted from Mauk et al. (1976).
Figure 25o Schematic for ozonation/UV irradiation apparatus.
119
-------
C2H5O -
C2H50 -
H2O
C-CH2
I
c-c-
s
II
S-P
o
H
-OCH3
-OCH3
H2O
hu
H2O
L
H COOH + H2O
^— ^C0+
H2O
03
P-SOH i_^H9O +
n H2;0 2
S
-(CH2)(CHOH)-COOH
°3
°
C2H5OH—^CH3COOH + H2O
03L^CHoOH +
3OH + C02
°3
HOCH2-CH2OH ^-^HOOC-COOH
Source: Mauk et al. (1976).
CO2 + H2O
+H2O
Figure 26. Schematic diagram of potential reaction of malathion and ozone/UV irradiation.
-------
Table 17 summarizes current results at the bench-scale level (20-liter
volumes) for detoxification of pesticides by combined ozone/UV irradiation.
The results are encouraging for individual pesticide AI as dilute solutions.
Only three classes of pesticides have been investigated to date. Success-
ful detoxification of DDT, PGP, Baygon®, Vapam®, and malathion has been accom-
plished. All other pesticide classes are potential candidates for detoxifica-
tion by this process* Organometallic pesticides may be converted to insoluble
metal oxides or hydroxides by this process, e.g., As, Hg, Zn, Cu, etc., and
collected by filtration.
To date, there have been no pilot-scale demonstrations of pesticide
destruction by combined ozone/UV irradiation.
Similar work utilizing the combination of ozone/UV irradiation is being
performed by Westgate Research Corporation (Zeff, 1977). Recently, Zeff and
co-workers have studied the treatment of wastewater that contains residues of
explosives manufacture (i.e., "pink water") and the treatment of pesticide
'intermediates in groundwater near Rocky Mountain Arsenal, Denver, Colorado.
The results of these studies are best described as preliminary, and details
have not been published. Cost estimates and other economic data are being de-
veloped for the treatment of explosives residues in process water (Roth, 1977).
Zeff is currently developing pilot-scale systems for further ozone/UV irradia-
tion studies. The systems will be able to process 4,000 to 40,000 liters/day
(1,000 to 10,000 gal/day).
Sonocatalysis and Catalytic Ozonation—
Chen and Smith at Southern Illinois University performed some interesting
studies on wastewater (Chen and Smith, 1971). These researchers studied the
oxidation of phenol and £-chloronitrobenzoic acid (OCNB) in solution and waste-
water by the joint combination of ultrasonic energy, air (or ozone), and by
an activated Raney-Nickel catalyst at room temperature. By means of a rather
simple apparatus involving a jacketed reaction vessel for controlling the tem-
perature, an ozone generator and gas sparger, and an ultrasonic generator (800
kHz) and transducer, the investigators showed that large decreases in chemical
oxygen demand (COD) and total organic content (TOG) were observed in 1- to
3-hr treatments.
Sonocatalytic ozonation of phenol produced a series of oxidized species
including catechol, hydroquinone, pyrogallol, and ultimately small amounts of
carbon dioxide and water. Thus, phenol in solution was reduced from 500 to
25 ppm by combined treatment with ultrasonic radiation, ozonation, and acti-
vated Raney-Nickel catalyst in 3 hr.
Other experiments with phenol at higher concentrations, e.g., 1 to 3 g
'phenol in 200 ml H20, were conducted for periods of up to 16 to 20 hr duration.
121
-------
TABLE 17. TYPICAL RESULTS OF OZONE/UV IRRADIATION OF PESTICIDES
N>
Pesticide
DDT
PCP
Ma lath ion
Baygon®
Vapam®
Solution
temperature
(°C)
30
30
25
25
25
Ozone
concentration
(ppra)
10
10
50
20
20
UV light
concentration
(w/f,)
1.32
1.32
1.32
1.32
1.32
Apparent
percentage
detoxification
> 99.9
> 99.3
> 99.8
>99.8
>99.3
Starting
pesticide
concentration
(ppm)
0.057
71.0
55.0
49.0
70.0
Residual
pesticide
concentrat Ion
(ppra)
< 0.0005
< 0.5
< 0.1
< 0.1
< 0.5
Total
time
elapsed
(min)
30
15
30
30
30
Source: Mauk e£ al. (1976).
-------
Principal products again obtained were catecho1, hydroquinone, quinone, and
pyrogallol.
Sonocatalytic experiments with a saturated solution of OCNB (~2 x 10"3 M)
using air, oxygen, or ozone/oxygen mixtures indicated partial loss of OCNB in
solution after 24 hr and production of three intermediate degradation com-
pounds:
0== =N—N—L
(postulated, unstable species)
(postulated)
(identified)
An alternate system for treating wastewater containing phenol and ethyl
acetoacetate has been investigated by Chen et al. (1975). These workers found
that ozonation utilizing a special Fe203 catalyst was very effective in re-
ducing COD and TOG in industrial wastewater in approximately 1 hr.
It is hypothesized that the catalyst promotes the use of two oxygen atoms
in the ozone molecule for oxidation in contrast to other ozonation procedures
which utilize only one oxygen atom per ozone molecule (Chen and Smith, 1976).
It is further proposed that catalytic ozonation may eventually compete very
successfully with other water purification processes through reduction of
ozone demand and, hence, the total cost of ozone. Current ozonation produc-
tion costs are $0.20 to $0.25/lb. The new catalytic ozonation process under
development may lower the effective cost of ozonation significantly (Chen et
al., 1975).
Recent experimental work by Chen and Smith has focused on chemically
catalyzed ozonation rather than sonocatalysis. These workers are now of the
opinion that essentially the same results for treatment of wastewater can be
accomplished by catalytic ozonation without generation and expenditure of
ultrasonic energy. Sonocatalysis and combination ozone/UV irradiation are
feasible processes for wastewater treatment but are inherently more expen-
sive than chemically catalyzed ozonation (Smith, 1977).
123
-------
No work has been attempted on pesticides or other hazardous materials
using sonocatalysis or catalytic ozonation, although there is sufficient pre-
liminary evidence to expect success. If such work is to be done, the progress
of treatment process should be monitored by measurement of the actual pesti-
cide species rather than TOG and COD.
Wet Air Oxidation (Zimmerman Process)
The principle of operation is that a solution of any organic compound can
be oxidized by air or oxygen if sufficient heat and pressure are applied. Thus,
at temperatures of 150 to 340°C and 450 to 2,500 psig, sewage sludges will be
oxidized to alcohols, aldehydes, acids, and finally at the higher temperatures
and pressures, to C02 and 1^0 in 30 to 60 min. Sulfur, nitrogen, and phosphorus
may remain in solution as salts. Heavy metals may be precipitated as sulfates,
phosphates, oxides or hydroxides, or may remain in solution (Astro, 1977).
Figure 27 presents a schematic flow diagram of wet air oxidation.
Zirapro, Inc., Division of Sterling Drugs, Inc., promotes use of this
process for sewage sludge stabilization. Lockheed Missiles and Space Company
has applied the concept to reclamation of potable water on spacecraft. In 1976,
the Lockheed Company sold its version of the wet air oxidation process to
Astro Metallurgical Corporation of Wooster, Ohio, who presently market it as
the Astrol™ Wet Oxidation Waste Treatment System.
The extent of actual pesticide destruction has rarely been determined;
the percent reduction in TOG is given instead. For example, studies on DDT,
2,4-D, and pentachlorophenol (PGP) have been reported in this manner (Astro,
1977). Other studies of the wet air oxidation process applied to Amiben®
herbicide process wastes indicate 88 to 99.5% destruction of the AI (Astro,
1977; Adams et al., 1976). Atrazine process wastes have reportedly been 100%
destroyed (Astro, 1977).
Various waste sources have been treated by wet air oxidation. However,
our discussion is restricted to published data related to pesticides and pes-
ticide process waste. Table 18 indicates some specific applications and the
degree of success in detoxification. Percentage TOG reduction measures resi-
dual total organic carbon as the present toxic material and all other organic
breakdown products.
The previous table of pesticidal applications of the wet air oxidation
process represents all the operating detoxification efficiency data readily
available. No other qualitative or quantitative data for pesticides are avail-
able to the public, although Zimpro, Inc., has performed additional confiden-
tial and proprietary research and development of pesticidal applications for
individual clients. According to one source at Zimpro, Inc.:
124
-------
Feed
Storage Tank
Pump
No. 1
Separator
Oxidized
Liquid
Heat Exchanger
Reactor
Reprinted with permission of Environmental
Science and Technology J9(4) 301 (1975).
Copyright by the American Chemical Society.
Air
lerJ^
No. 2
Separator
• Steam
-Water
Recycle Pump
Air Compressor
Figure 27. Schematic flow diagram of wet air oxidation.
125
-------
TABLE 18. WET AIR OXIDATION PESTICIDAL WASTE APPLICATIONS
Waste source
(specific constitutent)
Operating conditions
Temperature Pressure
°C Pa (psig)
Specific
TOG constituent
reduction removed
7=
7.
Amiben® herbicide process
(dichloronitrobenzoic acid) 280
s-Triazine herbicide process
(atrazine derivatives) 260
DDT 290
2-4-D 260
PGP 290
1.08 x 10?
(1,560)
8.27 x 106
(1,200)
1.03 x 107
(1,500)
8.27 x 106
(1,200)
1.03 x 107
(1,500)
96
46
60
81
94
99.5
100
Source: Adams et al. (1976); and Astro (1977).
126
-------
"Where dilute solutions of these materials are concerned, wet
air oxidation represents an exceptionally economical solution
to the problem as opposed to evaporation and incineration tech-
niques o We base this contention on a very sizable backlog of
both laboratory and pilot scale work. Unfortunately, confiden-
tiality restricts us from even disclosing the names of the cli-
ent firms or the scope of the work" (Flynn, 1977).
In the opinion of the authors of the present report, analytical results
for the specific pesticide active ingredients before and after treatment and
identification of the products of the treatment are needed to assess the ap-
plicability of wet air oxidation to pesticides. Merely monitoring the percent
TOG reduction is inadequate,. Much information is yet to be developed on the
use of wet air oxidation disposal for all classes of pesticides.
LIQUID-SOLID PHASE DISPOSAL PROCESS: CHEMICAL FIXATION
There is only one candidate chemical disposal process, chemical fix-
ation, that leads to disposal of toxic materials as a solid phase. The balance
of this subsection is devoted to a presentation of the Chemfix process. We
defer discussion of current land disposal operations until Section 7, since
these are not based on physical=chemical treatment of pesticide wastes prior
to disposal.
A chemical fixation process for the ultimate disposal of liquid wastes
has been advanced at least since 1971 (Anon., 1971). Originally developed by
Chemfix, Inc<>, of Pittsburgh, Pennsylvania, it is now marketed by Carborundum
Environmental Systems, Inc., Carborundum-Chemfix Division. The initial con-
ceptualization and experimental work was performed by J. R. Conner and has
been described in a patent (Conner, 1974a). Chemical fixation has been dis-
cussed in at least two engineering conferences (Conner, 1971 and 1974).
The essential steps in the Chemfix process are as follows: commercial or
domestic solid, liquid, or slurry wastes are mixed with an alkali metal
silicate in the presence of a setting agent, which causes the entire mixture
to gel and eventually to solidify and harden. Sodium silicate may be utilized
as either a solid or a solution (water glass). Setting agents include Portland
cement, lime, gypsum, and calcium carbonate. Figure 28 presents a schematic
diagram of the process.
Predisposal options for the solid wastes include chopping, shredding, or
crushing operations. The waste may then be combined with a silicate solution
and a setting agent to form a mixture which can be poured or pumped into ap-
propriately shaped molds; or the mixture can be pumped to land surfaces, e.g.,
abandoned strip-mining operations.
127
-------
00
Liquid or Sludge
Holding Tank
Dry
Chemical
Storage
Controls
& Pumps
-------
The final product, a chemically fixed waste material, is a solid matrix
and has been termed a pseudomineral (Conner, 1974b). The cross-linked, three-
dimensional array of covalent silicon-oxygen bonds and the polyvalent metal
ions attracted to oxygen anionic groups form an inorganic polymer which dis-
plays desirable long-term storage properties, including high stability toward
solubilization, and high melting point.
The metals which may form insoluble silicates, the gel structure which
acts to retain water or moisture in the waste, thfe setting agents which cause
the entire gel mass to form a solid, all aid in holding the waste firmly in-
tact and separate from groundwaters. Organic wastes may be hydrolyzed by the
alkaline medium or simply retained in the solid matrix with little decoraposi-
tione Bacterial growth does not normally occur in the physically immobilized
wasteo The latter points are of specific interest to the current assessment
of the Chemfix process.
Favorable claims made for the Chemfix process include:
* High continuous throughput rate
* Ability to process low solids wastes without dewatering
* Small volume increase due to chemical additives
* Ability to react with complex waste mixtures; e.g., metal finishing
wastes
* Controlled rate of solidification
* Controlled range of physical and mechanical properties for use as
landfill
* Low toxicity and leachability of final solid material
* Relatively low cost
* Mobility of the process unit
Of crucial importance to the application of this technique is the ques-
tion, How stable are chemically fixed wastes in actual environmental condi-
tions under the influence of ambient weather, light, heat, and microorganisms?
Claims are made that grasses and crops may be grown over chemically fixed
electronics manufacturing wastes containing highly toxic metal ions and metal
cyanides. No abnormal uptake of any of the metals by various grasses was ob-
served (Conner, 1974b).
129
-------
Acid leaching tests with sulfuric (pH 1*0), hydrochloric (pH 1.0), nitric
(pH 3*0), and acetic (pH 3.0) acids of chemically fixed waste that contained
large amounts of metallic compounds indicated that < 0.1 ppm of any metal ion
was released after the waste material had been exposed to the equivalent of
250 cm (100 in.) of rainfall as dilute acid.
Long-term changes in the chemically fixed waste include: drying and
shrinkage, loss of the gel structure, and possible microfracture; no increase
in leachability is claimed.
In spite of the wealth of practical experience and knowledge based on the
disposal of > 100 million gallons of a wide variety of industrial wastes,
pesticide disposal by the Chemfix process has apparently not been attempted.
Contact with representatives of Carborundum Environmental Systems, Inc., and
J. R. Conner produced no laboratory or developmental engineering data for any
pesticides.
Opinions were offered, however, on the potential applicability of the
Chemfix process to various types of pesticide wastes. This process was not
recommended for disposal of water-soluble pesticides. These materials would
tend to leach from the silicate matrix in the presence of groundwater if the
matrix should suffer microfracture. Oily or solvent-based pesticides are like-
wise not recommended for disposal. These materials are incompatible with the
aqueous gel structure and, in time, may tend to bleed from the matrix. Further,
there may be little or no decomposition of the pesticide wastes within the
matrix. Conner (1977) suggested that many pesticides might be handled much in
the same manner as low level radioactive wastes: treat the wastes by the Chem-
fix process, store in a drum, and dispose of the fixed water in a secure land-
fill (Class 1 site). This technique is a proven practical mode of operation.
A review of the limited data and these opinions suggests caution in con-
sidering routine disposal of pesticides by the Chemfix process at this time;
answers are needed to several questions about the basic process itself and
about the potential long-range environmental impacts of the use of this process.
»
CATALYTIC LIQUID PHASE DISPOSAL PROCESSES
This subsection of the report is concerned with two topics having a cata-
lytic basis for influencing the rate of chemical change. Specific examples
having a bearing on pesticide disposal or reprocessing include:
* Catalytic dechlorination utilizing nickel boride
* Reductive degradation utilizing metallic couples
Each detoxification process is described below.
130
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Catalytic Dechlorination Utilizing Nickel Boride
One promising area that Dennis and Cooper (1975) have pursued is that of
catalytic dechlorination by nickel boride which is obtained ir± situ from
nickel chloride and sodium borohydride. Thus, a series of studies of the treat-
ment of DDTj heptachlor, chlordane, and lindane by nickel boride have shown
that chloride ion is rapidly generated over 30 min at room temperature in
methanol=water mixtures0 Maximum dechlorination is obtained in methanol with
a molar ratio of pesticidesNaBH^sNi(II) is Isl5:0.5.
In the case of DDT, the primary products were:
l=Chloro=2, 2-bi s(j>=chlorophenyl )e thane
1, l^Bis^-^chloropheny^ethane
l=g~Chlorophenyl-l~phenyl ethane
[ 1,1-Diphenyl ethane
Lesser amounts of the following were formed:
l9l~Dichloro~2=£=chlorophenyl~2=>phenyl ethane
l=>Chloro~2=£=chlorophenyl=2~phenyl ethane
The presence of these materials was confirmed by combined gas chromatography/
mass spectrometry (GC/MS) (Dennis and Cooper, 1975).
The major product isolated in the dechlorination of heptachlor and chlor-
dane is given below:
\?—r~v—cl
(anti-form)
131
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No unreacted heptachlor remained in the reaction mixture after 30 rain, but no
totally dechlorinated heptachlor was found (Dennis and Cooper, 1976).
Other compounds present in lesser amounts were:
(syn-form)
Cl
Traces of further decomposition products were found, including a di-
chloro-compound,
Cl
Recently, these investigators have catalytically dechlorinated lindane
by use of alcoholic-nickel boride solutions. Thus, lindane (gamma-isoraer of
1,2,3,4,5,6-hexachlorocyclohexane) is converted rapidly to benzene (61 to 797,),
cyclohexene (16 to 35%)> and cyclohexane (3 to 11%) depending on the solvent
132
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mixture. No trichlorobenzene derivatives were observed, but traces of other
compounds having four and five chlorine atoms per molecule were detected by
combined GC/MS (Dennis and Cooper, 1977a).
The authors indicate that nickel chloride/sodium borohydride alcoholic-
aqueous systems which form nickel boride appear feasible as a possible dis-
posal method for highly chlorinated pesticides although they caution that the
toxicity and biodegradability of reaction product mixtures should be determined
(Dennis and Cooper, 1976). The process should only be considered useful for
small-scale applications due to solvent and sodium borohydride costs (Dennis
and Cooper, 1977b).
Reductive Degradation Utilizing Metallic Couples
A catalytic reductive degradation process utilizing metallic couples is
described in a U.S. patent by Sweeny and Fischer (1973). The claim is made that
various metallic couples (e.g., zinc/copper, iron/copper, aluminum/copper,
etc.) in the presence of dilute acids (pH 1.5 to 4.0) caused the decomposition
of DDT at or near room temperature. The data shown in the patent describe
decomposition of dilute DDT emulsifiable concentrate in wash water. Typically,
the concentration of an effluent containing 400 to 500 ppm DDT could be
lowered to — 1 ppm DDT in 1 hr at 75°C. Products of the reaction included 1,1-
bis-(£-chlorophenyl) ethane (oral rat 11)50 1,000 mg/kg) (Christensen and
Fairchild, 1976). Other reaction conditions and metallic couples yielded other
products, e.g., dimerized DDT formed by the loss of two chlorine atoms.
This reductive degradation technique has evolved to the pilot plant dem-
onstration stage, and wastes containing endrin, chlordane, and heptachlor are
being tested. Figure 29 presents a schematic diagram of the process. The sys-
tem consists of a filter to remove solids which might clog the catalytic
degradation column, a mixing chamber for pH adjustment and a reduction column
or bed (Sweeny, 1977). The process water to be treated for removal of halogen
containing organic materials is filtered, the pH is adjusted (6 < pH < 8) and
the influent, flows to a catalytic reduction bed which contains evenly distri-
buted sand and metallic particles of similar size. The column beds are 0.9 m
ID by 2.4 m in length (3 ft x 8 ft). The current installation can carry up to
400 liters/rain (100 gal/min).
Performance data are only available for a bench-scale operation which
processes 1.7 liters/min, but these indicate a reduction in aqueous concentra-
tion of endrin, chlordane, and heptachlor from 50 ppb to ~0.02 ppb. Current
work on a pilot plant demonstration of reductive degradation is in progress
(Des Rosiers, 1977).
133
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Influent
Source: Adapted from Sweeny (1977).
Effluent
Discharge
Figure 29. Schematic flow diagram for reduction degradation process.
134
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POTENTIAL IMPACTS
This subsection discusses the potential environmental and economic im-
pacts of pesticide disposal by various physical and chemical technologies.
Potential Environmental Impacts
We shall combine the various physical and chemical procedures within each
phase category as previously defined (gas, liquid, liquid-solid, and catalytic
liquid) to develop an overview of environmental impact.
Gas Phase Methods-
Microwave plasma degradation is a controllable method which yields
innocuous products like CC>2 and t^O, but also potentially hazardous products,
S02, CO, Cl2» HPOg, etc., depending on the pesticide. The latter materials
could be effectively retained in a cold trap and then allowed to enter an
alkaline scrubber unit for neutralization. The process has the advantage of
continuous monitoring by GC/MS and is interruptible if difficulties appear.
Further, the contemplated scope of utility is limited, and thus, the potential
for widespread adverse effects is minimized. In contrast to the photolysis
process, microwave detoxification appears to have definite practical advan-
tages and minimizes environmental impact and risk.
Attempts to destroy large quantities of unwanted pesticide by photolytic
degradation by surface spreading and direct exposure to the sun should be
made only after laboratory data and preliminary field trials have proved con-
clusively that the method is totally reliable, the volatility of unreacted pes-
ticide is not significant, the mechanism of destruction is known, the rate of
reaction is known, the final products, including principals and by-products
are known, and the question of residual toxicity has been answered by aquatic
bioassay.
Other special considerations may be required, e.g., if it rains prior to
complete degradation, will the excess water cause runoff contamination and/or
allow the material to penetrate the soil whereby exposure to UV light is
minimized? In exposure to heat and sunlight, will significant evaporation
losses of the pesticide occur prior to complete degradation? Will the final
products, including by-products, be volatile and will they impact on the
environment? If the pesticide reacts in the soil, will the final products or
by-products have impacts?
If, and only if, all of the above required facts are known, may the un-
wanted pesticide be spread on a suitable surface (e.g., soil or inert mem-
brane), sprayed with a suitable photosensitization chemical, and then allowed
to degrade by sunlight, heat, exposure to the air and moisture, etc. The
process and resulting effluents must be controllable at all times.
135
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We conclude that large-scale application of photolysis may have poten-
tial adverse environmental implications that cannot be evaluated with the cur-
rent data base. The very nature of the process does not readily lend itself
to conventional air pollution control devices (e.g., air scrubbing units) if
an adverse effect occurs. On the other hand, runoff control may be achieved
by containment. Protection from rain could in theory be achieved by temporarily
covering the surface area.
In the words of Plimmer (1977), "Without this basic data, there is little
point in discussing the question of installation design and calculation of
operating costs." The practical application of photolysis to degrade large or
small quantities depends on many factors still not fully understood in the
laboratory.
Liquid Phase Methods—
The procedures to be considered include:
* Activated carbon and resin adsorption
* Hydrolysis
* Molten salt bath methods
* Ozone/UV irradiation and other ozonation methods
* Wet air oxidation
Each procedure is controllable and interruptible through standard engi-
neering practices. Special consideration needs to be given molten salt bath
methods which may require scrubber units and/or traps to control vapors and
will require safety devices to protect the work environment and the immediate
surroundings.
The other processes in this category have a low environmental risk as-
sociated with their application. Activated carbon and resin adsorption con-
centrates pesticides from solution for further processing. The carbon or resin
is generally recycled for economic reasons, and the released pesticide must
be detoxified by an alternate process. Thus, the environmental impact of acti-
vated carbon and resin adsorption is nil up to the point of regeneration and
final disposal of the concentrated pesticide.
The various other liquid phase procedures have a low potential for en-
vironmental impact. All resulting degradation products will be innocuous if
the process has been operated properly. The question of residual solution
toxicity is one which can be answered only by final testing of the resulting
product mixture prior to release to the environment. Use of temporary holding
tanks or lagooning may be required.
136
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Liquid-Solid Phase Method—
The Ghemfix process immobilizes wastes and hazardous materials in a
silicate matrix. No experimental data exist for the disposal of actual pes-
ticides by this method. A potential exists for environmental insult by resi-
dues if the pesticide does not degrade or detoxify in the alkaline silicate
media. Further, the permanence of immobilization of the pesticides in the
silicate matrix is uncertain. If the pesticide is water soluble and does not
suffer chemical degradation, then its release from the matrix could affect
soil and water quality in the vicinity of the disposal site. One suggestion
that has been made to minimize environmental impacts in the disposal of pes-
ticides by the Chemifix process is to handle them in a manner similar to that
for low level radioactive wastes: bind the wastes in silicate slurry matrix,
drum them, and bury them in a secure landfill (Class 1 site). Such a proce-
dure should guarantee as nearly as possible the safe disposal of pesticides,
using the Chemfix process.
Catalytic Liquid Phase Methods—
Both processes, catalytic dechlorination using nickel boride and reduc-
tive degradation using metallic couples, are potentially controllable and
interruptible, if need be, to handle emergency situations. Catalysts consist
of metallic couples, nickel boride, or Raney-Nickel which may result in a
loss of traces of heavy metals in the liquid waste streams and thus may re-
quire further treatment of the effluent. The residual toxicity of the result-
ing pesticide waste streams must be tested prior to release.
Potential Economic Impacts
The potential economic impacts of various physical and chemical pesti-
cide disposal methods will be analyzed categorizing each process by phase as
was previously done for the environmental assessment. Large information gaps
exist, however, and economic cost comparisons are difficult to make.
Gas Phase Methods-
Microwave plasma destruction has inherent advantages over alternative
thermal techniques such as pyrolytic, incineration, and molten salt baths.
For example, since the energy for promotion of chemical reaction comes pri-
marily from free radicals rather than molecular motion (heat energy), the
entire detoxification/destruction zone operates only slightly above room tem-
perature, ~5CPc. The materials of construction, e.g., insulation, bulkheads,
etc., generally associated with furnace or incineration devices are consider-
ably simplified from a gross or physical standpoint. The apparatus has the
potential advantage of being made into a mobile unit, with a relatively low
initial cost and a leak-proof character.
137
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LPARL has provided cost estimates for destruction of phenylmercuric
acetate (PMA) in the current laboratory unit* Table 19 indicates that at a
feed rate of 3.0 kg/hr (6.5 Ib/hr) and 4.3 kw of microwave power and assuming
current costs of oxygen gas and electrical energy, the operating cost (not in-
cluding labor and overhead) may be as low as $0.15/kg ($0.07/ Ib).
A second cost estimate for the destruction of large quantities of PMA
utilizing a proposed 45 kg/hr (100 Ib/hr) unit has been offered by LPARL,
which includes recovery and sale of mercury metal. The following assumptions
were made in estimating net profit per pound of PMA destroyed by the microwave
plasma unit:
1. Electrical costs are $0.012 kw-hr, industrial usage.
2. Liquid oxygen costs are $0.005/SCF, large volume usage. Add $3,000/
year storage fee.
3. Steam costs are $4.40/1,000 kg ($2.00/1,000 Ib).
4. Labor costs are one-half man per automated unit, i.e., one man op-
erates two units, $12/hr.
5. In the case of PMA, the credit for metallic mercury is $3.30/kg
($l»50/lb). This is based on a requirement for future purification. At pres=
ent, the purity of the recovered metal has not been determined. A more pure
product obviously has greater value, up to $8.80/kg ($4/lb).
6. The estimate for capital costs is $100,000.
LPARL assumes a three-shift, 330 day/year operation. PMA throughput is
23 kg/hr or 180,000 kg/year (50 Ib/hr or 400,000 Ib/year). Process require-
ments to destroy PMA on a per pound basis are: oxygen, 4.3 SCFj steam, 1<>5 Ib;
electrical energy, 1.6 kw-hr. Table 20 summarizes total process costs and net
profit per unit weight of PMA destroyed.
For detoxification of material such as malathion or PCB wastes where few
or no useful by-products are recoverable, the costs may be higher. In oxygen
and steam plasmas, for example, the costs are calculated as $0.48/kg and
$0.44/kg, respectively.
All cost data contained in Tables 19 and 20 were estimated in 1976 and
may be updated to 1977 price levels using an 8%/year inflation rate as a first
approximation.
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TABLE 19. ELECTRICAL AND CARRIER GAS COSTS FOR PLASMA REACTIONS IN LABORATORY REACTOR
VO
Effective
(absorbed)
Material
PMA-30
PMA-30
PMA-30
Carrier
eas^/
°2
°2
°2
microwave
power
(kw)
4.6
4.0
4.3
Feed rate
(g/hr)
(Ib/hr)
1,020 (2.25)
2,380 (5.25)
2,950 (6.5)
Carrier gas
flow
(std. Jl/hr)
(scfh)
960 (34)
V
792 (28)
792 (28)
Gas cost
($/lb)
0.18
0.064
0.054
Total
power
consumed
(kw-hr/lb)
4.7
1.9
1.6
Power
cost Total
($/lb)-' ($/lb)
0.06 0.24
0.023 0.087
0.019 0.07
cost
($/kg)
0.53
0.19
0.15
Source: Bailin and Hertzler (1976).
a/ 02, $0.012/ft3.
b_/ kw-hr, $0.012, industrial usage.
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TABLE 20. TOTAL PROCESS COSTS AND NET PROFIT FOR
MICROWAVE PLASMA DESTRUCTION OF PMA
Variable costs
Operating labor
Maintenance (47° of investment)
Oxygen or steam
Electricity
Total variable costs
Fixed costs
Taxes and insurance (2%/year)
Capital recovery (10 years - 10%)
Total fixed costs
Total annual costs
Total income from recovered mercury
Total net profit
Net profit oer pound tr.ea.ted
Net profit per kilogram treated
Oxygen
$47,020
4,000
11,600
7,680
70,300
2,000
16.250
18,250
88,550
108,000
19,450
0.049
0.108
Steam
$47,020
4,000
1,200
7,680
59,900
2,000
16.250
18,250
78,150
108,000
29,850
0.075
0.165
Source: Bailin and Hertzler (1976).
140
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As microwave power technology advances, the electrical costs should de-
crease as the result of improvements in the coupling of microwave power to the
plasma reactors. The potential for steam plasmas with their low cost, plus
their capability to form their own vacuum, is readily apparent and can, there-
fore, be considered for further reductions in electrical power requirements.
The above data have been derived for a permanent-type disposal center,
which may then be compared with other methods operating at similar levels of
throughput. The costs associated with a projected mobile or truck-bed type
detoxification unit will vary, depending on the initial capital and labor
costso The latter will depend in part, on the distance to the user's site and
the toxicity of the materials to be treated*
The economic impacts of the large-scale application of photolytic degra-
dation technologies are unknown. Significant factors may include: land
availability and cost; amount and kind of chemicals required; application
costs (including any aircraft over-spraying operations with photosensitizers)j
cost of liners, covers, and dikes; labor; monitoring; etc. As stated earlier
in this report, the economic aspects of photolytic degradation have not been
adequately addressed and must await successful practical laboratory and field
demonstrations before the needs and limitations of this technology can be fur-
ther defined°
Liquid Phase Methods-
Various liquid phase degradation procedures have been proposed, but few
have been demonstrated on a large scale* Economic cost estimates are available
for activated carbon or resin adsorption and wet air oxidation. Land avail-
ability and cost, as well as costs of reactors, chemicals, labor, energy, and
emission control facilities need to be estimated.
Economic cost estimates have been developed for two examples of waste-
water treatment by activated carbon and resin adsorption* Cost data for car-
bon adsorption of 2^4-D, MCPA, and 2,4-DB wastes cited earlier in Section 6
are presented in Table 21 (Rizzo, 1972). The estimated capital investment and
direct operating costs have been updated to 1977 using an inflation rate of
8%/year.
The second economic cost estimate involves a facility which treated
chlorinated pesticides in wastewater (Kennedy, 1973). Table 22 presents vari-
ous economic costs to treat an effluent containing 200 ppm of chlorinated pes-
ticides at 600,000 liters/day (150,000 gal/day). The resultant effluent con-
tains 1 ppm pesticides. The table compares costs for conventional treatment
by granular activated carbon and resin adsorbent. The lower costs associated
with resin adsorbent are attributed to more rapid adsorption kinetics with a
correspondingly low volume of adsorbent required and greater regeneration ef-
ficiency.
141
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TABLE 21. OPERATING CHARACTERISTICS AND ECONOMIC COSTS
ASSOCIATED WITH HERBICIDE REMOVAL FROM
WASTEWATER BY CARBON ADSORPTION
Category Quantity
Flow rate 600,000 liters/day (150,000 gal/day)
Influent contaminants
phenols and cresols 10 ppm
chlorophenols and chlorocresols 100 ppm
chlorophenoxyacetic acids 100 ppm
octyl and other alcohols 1,000 ppm
total dissolved inorganic salts 62,000 ppm
Effluent contaminants (total 1 ppm
phenolics)
Contact time 280 min
Total carbon adsorber beds 8,200 kg (18,000 Ib)
Estimated capital investment (1972) $300,000
(1977) $420,000
Direct operating costs (1972) $0.095/1,000 liters ($0.36/1,000 gal.)
(1977) $1.33/1,000 liters ($0.50/1,000 gal.)
Source: Rizzo (1972).
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TABLE 22. ECONOMIC COST COMPARISONS FOR TREATMENT OF CHLORINATED
PESTICIDES WASTEWATER BY ACTIVATED CARBON AND RESIN
ADSORBENT
Granular activated
Category carbon Resin adsorbent
Capital investment (uninstalled) $175,000 $99,500
Operating expenses—' $73,000/year $45,150/year
Total operating costs^/ $0.35/1,000 t, $0.22/1,000 £
($1.33/1,000 gal.) ($0.83/1,000 gal.)
Source: Kennedy (1973).
!
a/ Includes equipment depreciation over 10 years.
The estimates in Table 22 by Kennedy (1973) are for the year 1972. If
these costs are adjusted to reflect 1977 price levels, the total operating
costs are estimated to be $0.49/1,000 liters using activated carbon and
$0.31/ 1,000 liters using resin adsorbent.
Hydrolytic and other simple chemical treatment methods have not received
wide-scale application, and no economic cost estimates have been developed
for them. In general, simple chemical treatment methods where feasible may be
relatively less expensive compared to other capital and energy intensive
alternatives, e.g., molten salt bath procedures.
In the absence of actual cost data for the capital investment, and op-
erating and depreciation costs per pound of pesticide destroyed, we estimate
the total cost of a mobile molten salt bath combustion unit with baghouse and
reprocessing components for 5 years of operation as follows:
Capital investment: $1.0 million
Operating costs (5 years):
Labor ($60,000 to $100,000/year) $0.3 to $0.5 million
Energy ~|
Maintenance > (5 years) $1.0 million
Raw material I
Total cost $2.3 to $2.5 million
143
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We assume 180 days/year operation at 2.7 Ml/day (3 tons/day) of pesticide
processed. Thus, the total output over 5 years is 2,450 MT (2,700 tons) of
AI. The cost per unit weight of pesticide processed is $l,000/ton, $0.50/lb,
or $1.10/kg.
This estimated cost would appear to place molten salt bath procedures in
an unfavorable economic position compared to other alternatives.
No cost estimates are available for the destruction of pegticide by
ozone/UV irradiation. Principal capital equipment costs include the reactor,
ozone generator and power supply, and the UV irradiation source and power
supply. Principal operating costs include electrical energy and labor. In
general, ozonation methods would be more costly than simple chemical treat-
ment but less costly than more energy-intensive methods. Ozonation processes
may be competitive if applied to dilute pesticide solutions on a large scale
as in water purification.
Economic cost estimates for wet air oxidation have been reported by
Adams et al. (1976) for a Zimpro, Inc., system to treat Amiben® herbicide
waste process waters. The wastes treated were the isomers of dichloronitro-
benzoic acid rather than the AI itself, dichloroaminobenzoic acid. Additional
waste treatment after the wet air oxidation step includes extraction neutral-
ization, and activated carbon treatment. Estimated costs are given in Table
23. The costs may be updated to 1977 by applying an 8% price level increase.
Thus, estimated total operating costs may be near $980,000 per year, or $0.39/
kg ($0.18/lb).
Liquid-Solid Phase Method-
Chemical fixation costs for disposal of pesticides have been estimated at
$0.05/liter plus transportation costs and landfill fees if the wastes are
chemically fixed in a silicate matrix and the wastes are drummed (Conner,
1977). This represents a relatively low cost method if it is environmentally
acceptable.
Catalytic Liquid Phase Method—
These procedures are still under active research and development, and
economic cost comparisons have yet to be developed. Catalytic dechlorination
utilizing nickel boride is almost certain to be an expensive procedure since
the cost of sodium borohydride is near $17.60/kg in carload lots ($8.00/lb)
(Chemical Marketing Reporter, 1977).
Reductive degradation utilizing inexpensive metallic couples to detoxify
pesticides holds promise of a cost-effective procedure. Cost estimates are
under development (Des Rosiers, 1977).
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TABLE 23. ESTIMATED COSTS OF WET AIR OXIDATION OF AMIBEN® WASTE
Category
Volume and cost
Cost per
unit weight
Capacity
Pesticide loadings 5%
concentration
151 cu m/day
(40,000 gal/day)
7,600 kg/day
(16,700 Ib/day)
Estimated capital investment
Variable operating costs
Fixed operating costs
Additional operating cost for
follow-on treatment
Total estimated operating costs
(330 day/yr operation)
$2o2 million
$299,100/yr
$594,000/yr
$15,000/yr
$908,100/yr
$0.119/kg
$0.239/kg
$0.006/kg
$0.364/kg
$0.165/lb
Source: Adams et al. (1976).
145
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FUTURE RESEARCH NEEDS
Many of the pesticide disposal methods discussed in Section 6 are under-
developed and remain at the bench or pilot plant levels. Further, basic en-
vironmental impacts and economic cost estimates have yet to be determined* On
the other hand, at least three methods (activated carbon or resin adsorption,
wet air oxidation, and reductive degradation) are at or near the point of
practical demonstration* This.subsection :wi11 indicate future research needs
for various pesticide disposal methods* The organization of topics remains un-
changed*
Microwave plasma Technology
!. ' '
This technology is being advanced from the bench scale, 0.5 to 3.0 kg/hr
(1 to 7 Ib/hr), to what has been described, as an expanded scale, 4.5 to 14 kg/
hr (10 to 30 Ib/hr). It remains, however, largely an investigative tool.
Destruction of representatives of several classes of pesticides, including an
organometallic material, have been demonstrated.
Development of a practical device for destroying 25 to 50 kg/hr (50 to
100 Ib/hf) seems highly probable. Such a Device would be mainly of value to
hospitals, clinics, research facilities, Industrial firms, educational institu-
tions, etc*, which must dispose of relatively small quantities of toxic mate-
rials. It femains to be seen if large-scale units, 500 kg/hr (1,000 lb/hr)>
can be fabricated and successfully and economically operated. Such units could
be valuable in solving pesticide field disposal problems* Continuing develop-
ment of this detoxification technique is required, with the goal of developing
larger units or banks of units which are mobile.
Photolysis •;;
This method has been demonstrated at 'the practical level only for the en-
vironmental degradation ofjTCDD, Other photolysis demonstrations for several
classes of pesticides have been made at the research level, and these remain
merely laboratory, albeit important, studies. The entire photolytic process
is undefresearched, underdeveloped, and hence, underutilized. Further research
and development in this field is required, with the goal of practical demon-
strations of field disposal of pesticides*
* '* !"
The progress made in the area of pesticide photolysis over the last 15
years or1, so has been slow, but the area of investigation has been fraught with
experimental difficulties. Early investigations focused on qualitative obser-
vations; these were followed by studies that focused on identification and
determination of structures 6f substances formed. Investigations have proceeded
from laboratory conditions^ using pure materials, to field conditions in which
such factors as light, air, water, pesticide AI, and the formulated synergists
146
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are all considered in the photolytic process. The concept of photosensitiza-
tion has not been capitalized upon*
Perhaps Crosby (1977) assessed the state of the art of photolysis as well
as any one when he stated, "Although photoreduction is hardly a panacea, it
obviously holds promise for the natural destruction of residual chemicals, the
destruction of toxic wastes from manufacturing and even the intentional decon-
tamination of polluted environments." It need hardly be emphasized that the
data base for rates and efficiencies of photochemical reactions must be ex-
panded o
Activated Carbon and Resin Adsorption
These methods are feasible for removing pesticides in water at low con-
centrations (< 100 ppm). Demonstrations using an Amberlite™ resin are in
progress at Velsicol Chemical Company in Memphis, Tennessee. But in its pres-
ent state this technology is not useful for solving field disposal problems
.for pesticideso It is much better suited for handling process waters at the
;point of manufacture or formulation. Continued development of this and simi-
.lar projects for removal of pesticides from process wastewater is advisable.
Hydrolysis
Simple alkaline hydrolysis appears viable as a potential method of field
disposal for pesticides in certain pesticide classes. This method has been
demonstrated at the research level by various investigators. To the best of
our knowledge, no recorded case exists of the large-scale use of alkaline
hydrolysis to solve a field disposal problem. But the technology is complete
and simple and may be effective for many organophosphorus and carbamate com-
pounds providing there is no residual toxicity problem, as observed by Meier
et al. (1976). Large-scale application of alkaline hydrolysis or any chemi-
cal treatment method may result in severe heat of mixing or heat of reaction
problems and resulting hazard to workers and the environment.
Kennedy (1969, 1970); Dennis (1972); Ottinger (1973); and Lawless et al.
(1975) all recommend alkaline hydrolysis for certain pesticides. Wolverton's
work (1973) using monoethanolamine in a glycol ether is potentially useful
for hydrolyzing organophosphorus pesticide spills and rinse waters occurring
from aircraft spraying operations.
The evidence in the literature is convincing regarding the potential
utility of alkaline hydrolysis for handling certain pesticide field disposal
problems. Questions regarding potential residual toxicity of the resulting
products and solutions must be answered.
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Molten Salt Baths
Demonstrated destruction of several classes of pesticides at the re-
search scale has been achieved. Although no tests at the pilot plant scale
have been made up to the present time, the technique may well work satisfac-
torily at considerably larger throughput rates than have been attempted thus
far. Atomics International has designed a mobile molten salt bath unit for
handling field disposal problems of toxic materials. However, the project is
inactive at present for lack of funding. Environmental and economic cost im-
pacts need to be determined.
Special attention must be given to organometallic or metal-based pesti-
cides. The question of metal volatility during combustion must be investi-
gated. Also, if the metal remains in the carbonate melt after pesticide de-
struction, the melt itself may be hazardous; e.g., combustion of an organic
arsenic compound may yield sodium arsenate, a highly toxic material.
Ozone/UV Irradiation
Several pesticides have been subjected to combined ozone/UV irradiation
at the research level, but no work at the pilot plant level has been attempted.
Pesticide classes which have been proven susceptible to destruction and/or de-
toxification include: chlorinated hydrocarbons, organophosphorus compounds,
and carbamates.
The process appears more applicable to the disposal of dilute pesticide
solutions than to concentrated pesticide wastes or unwanted supplies. Environ-
mental and economic cost impacts are lacking.
Sonocatalysis and Catalytic Ozonation
Initial work indicated detoxification of hazardous materials could be
accomplished by a combination of ultrasonic energy, air (or ozone), and
activated Raney-Nickel catalyst. No pesticides were tried although phenol and
£-chloronitrobenzoic acid destruction was studied. The principle of sonocatal-
ysis has been abandoned on purely economic grounds in favor of chemically
catalyzed ozonation.
Sonocatalysis or catalytic ozonation appears to offer the same advan-
tages (and disadvantages) as ozone/UV irradiation regarding potential dis-
posal of pesticides. Ozonation technology remains underresearched and under-
utilized.
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Wet Air Oxidation
This technique has wide potential application, but it remains under-
developed and underutilized. The only published data refer to destruction of
Amiberi® and atrazine process wastes. More research and development work, in-
cluding analytical evaluations, is advisable before a proper assessment can
be made of the field disposal application of wet air oxidation for destroying
and/or detoxifying pesticides. Economic cost estimates are available but not
an environmental impact assessment.
Chemical Fixation
This process has proven valuable for disposing of many kinds of hazardous
and/or toxic wastes, e.g., .household refuse, acid mine sludge, pickling liquor,
etc. However, no information exists pertaining to pesticides. Contact with
Carborundum's Chemfix Division produced no additional information. This tech-
nology remains untried with pesticides.
* Potential disposal applications include slightly soluble AI and finished
formulations, e.g., clays, dusts, granules, etc. Water-soluble or solvent-
based pesticides are probably not good candidates for disposal by chemical
fixation. On the other hand, organometallic and inorganic pesticides which
cannot be detoxified by any means may well be safely disposed in this manner
although this has not been attempted.
Chemical fixation is at best an encapsulation process, and its applica-
tion to pesticide disposal is incompletely evaluated.
Catalytic Dechlorination Utilizing Nickel Boride
This experimental batch process rapidly dechlorinates highly chlorinated
pesticides at room temperature in the relatively short time of 30 min. The
resulting product mixture contains many partially dechlorinated species; total
dechlorination is generally not observed. The method has the advantage of not
requiring complicated apparatus or hazardous reactants. Continued research
and development is advisable. Sodium borohydride chemical costs are very high
and may ultimately dominate all other considerations.
Reductive Degradation Utilizing Metallic Couples
This,technique has advanced from the research scale to pilot plant dem-
onstration scale (Sweeny, 1977 and Des Hosiers, 1977). Much experimental work
needs to be verified on this scale, and operating parameters need to be more
carefully defined. The process appears to be potentially most useful for very
dilute wastewater containing halogeriated pesticides.
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Reductive degradation appears to be strongly dependent on the degree of
halogenation of the individual pesticide. In our opinion, the technique has
not been thoroughly investigated, nor has an adequate data base been generated
for proper assessment* It is doubtful that the principle of operation would
apply to pesticides other than highly chlorinated types since the driving
force appears to be the formation of metallic chlorides* Nevertheless, the
process deserves attention for possible application to select dilute pesticide
solutions.
Synopsis
In the preceding reviews favorable comments were made on most of the
candidate disposal methodologies, but one should recognize that the technical,
environmental, and economic bases needed for a really definitive or critical
assessment are quite inadequate. Almost without exception, each of these tech-
niques for destruction/detoxification of pesticides and their formulations re-
mains a research technique. Few are near the pilot plant scale, and the poten-
tial environmental impact of these techniques has not been adequately examined.
Cost and other economic data have been tentatively given for only a few proc-
esses. As the processes advance beyond the research level to the pilot plant
scale, we may expect engineering and economic cost estimates to be forthcoming.
At the same time, much additional study must be given to the potential environ-
mental impact if a given technology is utilized for the field disposal of pes-
ticides and their finished formulations.
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SECTION 7
LAND DISPOSAL METHODS
INTRODUCTION
Land disposal of pesticides is widely used. This method requires minimal
waste handling and treatment, thereby reducing cost. However, current emphasis
on potential environmental impact is stimulating more rigid guidelines for the
handling and disposing of hazardous wastes. Requirements for more sophisticated
landfill design, procedures and monitoring are already being implemented in
Jmany areas0
For purposes of definition, land disposal shall include all methods by
which waste is deposited in or on lands Since this analysis is centered on
pesticides, the methods receiving the most attention will consist of procedures
characteristic of hazardous waste elimination.
The discussion of land disposal methods is divided into five areas: (a)
a description of methods; (b) current management of pesticide wastes in dis-
posal sites! (c) an examination of related research; (d) environmental and
economic cost impacts; and (e) future research needs.
METHODS OF LAND DISPOSAL
The five methods listed below outline the scope of land disposal:
* Burial
* Encapsulation
* Well Injection
* Infiltration/Evaporation Basins
* Soil Incorporation
Burial is the most widely used procedure for pesticide disposal in haz-
ardous waste landfills (Ghassemi and Quinlivan, 1975). This manner of handling
discarded pesticides involves covering the unwanted material with soil
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(usually heavily laden with clay and/or organic matter) in low areas or in
trenches used exclusively for such chemicals.
Encapsulation is the fixing of the pesticide in a sheath or container of
concrete, asphalt, or a synthetic polymer prior to burial or storage. The
encased chemical is isolated from its surrounding environment and preserved
for possible future recovery.
There are two different types of well disposal: (a) deep-well injection
entails pumping or draining wastes into underground cavities located beneath
and completely apart from any usable groundwater; and (b) shallow dry wells
and other man-made covered pits with perforated or permeable walls are em-
ployed as a dispersal system for dilute residues, especially mix and spray
tank rinsings. Here, isolation from water supplies and cultivated land is
essential since the avenue of disposal is dilution and biodegradation in the
surface water and soil of the surrounding area.
Infiltration/evaporation basins are best suited for hot, dry climates.
Solar evaporation concentrates toxic solids, which then must be periodically
landfilled, while simultaneously making.room for additional waste. In some
cases, the system allows a portion of the liquid to "infiltrate" the subsoil.
Soil incorporation includes a variety of surface soil-disposal tech-
niques: spraying, tilling, or flooding the soil with the discarded material.
With this variety of techniques, many types of pesticide wastes can be
disposed. Solids may be buried and/or encapsulated. Liquids may be buried in
sealed containers, deposited in disposal wells or infiltration/evaporation
basins, or sprayed on isolated land.
CURRENT MANAGEMENT OF PESTICIDE WASTES IN DISPOSAL SITES
Hazardous waste management practices and procedures in the United States
have improved in recent years through the creation of thoughtful and practical
legislation. The laws, regulations, and guidelines for handling hazardous
waste in California have been among the most comprehensive in the United States
(California Department of Health, 1975).
The State of California has defined and set aside 13 acreages as Class
1 Hazardous Waste Disposal Sites. Class 1 sites are those which present no
possibility of discharge of pollutant substances to usable waterso These sites
are the major depositories for hazardous and liquid wastes and are certified
by the Regional Water Quality Control Boards as suitable to receive Group 1
wastes. Group 1 wastes include agricultural wastes, pesticides, and pesti-
cide containers as well as other hazardous materials. As such, Group 1 wastes
must be considered potentially harmful to water quality and present occupa-
tional and health hazards.
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At present only one site, Big Blue Hills, in Fresno County is specifi-
cally reserved for hazardous agricultural wastes and principally handles un-
rinsed pesticide containers. This site occupies 32 acres and is estimated to
be operational from 1974 to 1995. Approximately 150 cu m/day (200 cu yards/day)
of empty containers may be disposed daily although the site is open only 20
days/year (Ghassemi and Quinlivan, 1975; Storm and Margitan, 1975). Trench
burial and compaction of empty pesticide containers to a depth of 6.1 m (20
ft) are the primary modes of disposal.
The Big Blue Hills site operation is guided by the following operational
details:
* Hazardous wastes may be unloaded by transporting personnel under the
supervision of site personnel.
* Security fences are maintained around the individual hazardous waste
areas.
5 * Monitoring of the hazardous waste areas by visual inspection is per-
formed.
* Preventive and safety procedures are observed for personnel.
* Formal emergency contingency plans exist.
* Operations manual and rules for personnel have been developed.
To date there has been only one incident involving the disposal of haz-
ardous waste materials at this site. On April 24, 1975, an explosion occurred
during the initial crushing and can compaction operation when a tractor dozer
ran over six drums which contained acetone/methanol solvent mixture that was
not identified on the manifest. The drums ruptured, and the liquid contents
and vapors exploded and started a fire which caused extensive damage to the
dozer. Fortunately, there were no serious injuries to the operator or other
personnel.
California Assembly Bill No. 598 (1973) deals with hazardous waste con-
trol by:
* Defining various terms involving disposal or processing of hazardous
waste and disposal sites.
* Establishing a hazardous waste technical advisory committee.
* Devising a list of hazardous and extremely hazardous wastes which
have immediate or persistent toxic effects to man and wildlife and a
resistance to natural degradation of detoxification processes.
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* Setting standards and regulations for handling, processing, and dis-
posal of hazardous and extremely hazardous wastes.
* Requiring that a manifest, or liquid-waste hauler record, be issued
describing the nature of the waste to be transported from the place
of origin to the disposal site.
* Establishing procedures for the evaluation and coordination of re-
search and development regarding methods of hazardous waste handling
and disposal.
* Setting disposal fees based on tonnage disposed at each site.
* Establishing enforcement by the State Department of Public Health or
any local health officer or any local public officer as designated
by the director.
Assembly Bill No. 598 has been in existence since July 1, 1973, and has
been reasonably successful in managing the transportation and disposal of haz-
ardous waste materials. The greatest problems in the application of the law
center upon mislabeled and insufficiently identified hazardous waste.
Assembly Bill No. 598, Article 7, provides for the establishment of pro-
cedures for evaluation and coordination of research and development of methods
of hazardous waste handling and disposal. Further, the Bill directs that ap-
propriate studies relating to hazardous wastes may be conducteds According to
the California Department of Health the following areas are currently under
study:
* Air emissions from industrial disposal sites.
* Total input to California Class 1 disposal sites (a sampling and
analytical study).
* Development of standardized waste sampling and analytical procedures.
* Development of waste compatibility guidelines.
* Compositions and environmental behavior of tannery wastes.
Several publications will be available in the near future (Stephens, 1977).
RESEARCH AND DEVELOPMENT
The following examination of current research and development is centered
primarily on the question of whether or not the given waste is properly im-
mobilized. Unlike incineration, biologicals or physical-chemical treatment of
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unwanted pesticides, land disposal does not directly address the question of
detoxification* Natural processes are expected to destroy the pesticidal agent
eventually, but the main intent of the method is isolation or controlled re-
lease into the environment with adequate dilution to prevent or lessen harm-
ful effects.
Information representing two general areas will be presented: (a) re-
search on the leaching of pesticides; and (b) soil incorporation studies.
Pesticide Leachate
Tracing pesticide leachate and monitoring the decline in groundwater and
soil concentration yields useful data in assessing the fate of pesticides ap-
plied to land surfaces or buriedo Four studies will be discussed and results
will be summarized in cases where the work has been completed.
A study was undertaken by the Sanitary Engineering Research Laboratory
(SERL) of the University of California, Berkeley, for the Army Medical Re-
search and Development Command in 1974. The two-fold objectives of this
project were to: (a) investigate the fate of pesticides in wastewater dis-
posed of by irrigation on soil; and (b) determine the subsequent changes in
mineral quality of the underlying groundwater. The pesticides used in the
study were Diazinon®^ malathion, carbaryl, and 2,4-D (Klein, 1974).
One series of experiments was carried out using large lysimeters contain-
ing 1»5 m (5 ft) depths of five soils~Yolo silty loam, Reiff very fine sandy
loam, Oakley sand, gravelly river sand, and Delta peat. Other experiments were
conducted on two field plots consisting of Yolo silty loam and Reiff very fine
sandy loam, respectively, and of 37.2 m (400 ft) surface area. At both loca-
tions 0.1 mg/liter concentrations of the four biocides were added to sewage
effluent irrigation water. The lysimeter studies included the following vari-
ables: distilled water slugs to simulate rainfall; addition of monovalent
(Na) and divalent (Mg) cations; and elevated sewage loads. The field plots
were subjected to normal outdoor precipitation and similar cation slugs. On
both sites,'movement of the test chemicals was carefully monitored.
After 43 weeks of experimentation, no significant accumulation or trans-
location problems were observed in the lysimeter studies.'However, one un-
explained inconsistency appeared in the form of 2,4-D movement through the
Yolo soil. The nature of the soil and its moisture content seemed to have more
influence on the subsoil water quality than did the applied wastewater.
The period of testing at the two field plots was 41 weeks, and results
there agree with the lysimeter findings. The researchers did note, however,
sizable pesticide movement under two extreme circumstances, one being high
fluid levels combined with removal of plot vegetation, and the other being
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extreme drying and cracking in the soil profile. The capacity of the differ-
ent soils to accomplish biological degradation was given credit for much of
the promise shown by this disposal technique.
'A second study was performed by the Agronomy Department at Oklahoma State
University for the Environmental Protection Agency, NERC-Corvallis, Oregon,
in 1974. The goal was to assess the use of soil parameters in describing
movement of pesticide leachate by a mathematical model (Davidson, 1975).
Experimental results from laboratory and field studies on the movement
of the herbicide, fluometuron, through soil were used to test the validity of
solutions of a differential equation for solute transport. Laboratory portions
of this investigation utilized calcium-saturated Norge loam soil and Cobb fine
sandy loam as the soil media. The field portion was conducted on Teller sandy
loam near Perkins, Oklahoma. The data demonstrated the feasibility of predict-
ing the movement of pesticide leachate by a mathematical model.
The adsorption and desorption isotherms studied were too complex mathe-
matically to be represented by a single-valued function. Some of the factors
responsible for complicating the pesticide mobility analysis were soil-pore
geometry and size, variance in the soil-water ratio, overlap of several adsorp-
tion and desorption cycles in the same soil profile, and the influence of bio-
logical degradation. Experimental results yielded maximum herbicide concentra-
tions in the migrating water solution lower than that predicted mathematically,
suggesting that a portion of the fluometuron was irreversibly adsorbed to soil.
Kinetic adsorption-desorption models for herbicide mobility were found
to be inadequate at high average pore-water velocities. These models were more
useful at low average pore-water velocities, but kinetic rate coefficients
were difficult to measure. Losses of fluometuron through the soil column were
greatest when the chemical was applied to wet soils.
The third study is a more recent effort by Davidson et al. (1978) which
examines the equilibrium adsorption isotherms of 2,4-D, atrazine, terbacil,
and methyl parathion in four soils. (The scope of this research is not limited
to pesticide leachate studies; but, for the sake of continuity, the remainder
of the current work that has been done by Davidson and his co-workers will be
described at this time.) The work is of particular interest because the level
of applied pesticide ranges from 10 to 20,000 g,g/g of soil. The upper end of
this range does simulate the high concentrations one would expect as a result
of land disposal activities.
The research was carried out in laboratory apparatus in the Soil Science
Department of the University of Florida, Gainesville. Column displacement ex-
periments were done in 15-cm glass cylinders with a cross-sectional area of
45 cm . Adsorption experiments were performed in agitated, screw-cap test tubes
162
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over 48-hr test periods. Both procedures employed a ^C tracer which allowed
the quantification of pesticide movement or adsorption. The soils utilized
were Webster silty clay loam from Iowa, Cecil sandy loam from Georgia,
Glendale sandy clay loam from New Mexico and Eustis fine sand from Florida.
Microbial metabolic activity and pesticide degradation were also noted
in separate procedures. Microorganisms that were isolated from incubated
(28°C) soil-pesticide cultures were identified and enumerated using a dilu-
tion plate count method. Metabolic activity of soil microbes was measured by
quantifying C02 production from aerated samples (aeration gas contained no
C02)• Pesticide degradation rates were determined by measuring the evolution
of l^c to CC>2 from l^Olabeled pesticides in soil-pesticide cultures during
an 80-day period. Duplicate microbial activity and pesticide degradation ex-
periments were run using both technical grade and formulated chemicals. A
fifth soil, Terra Ceia muck from Florida, was also used in portions of these
soil respiration experiments.
Results indicate that pesticide movement through water-saturated soil may
be represented by the Freundlich equation (S=KCN). K and N are constants ob-
tained for a given soil-pesticide combination using a least-squares fit, S
is the microgram weight of pesticide adsorbed per gram of soil and C is the
microgram weight of pesticide per milliliter of influent solution. Adsorption
sites were not saturated at any concentration tested, even when pesticide-
saturated solutions were employed. As pesticide concentration in the various
experimental solutions was increased, soil adsorption also increased, but not
at as great a rate. Higher concentrations of pesticide allowed greater pesti-
cide mobility in all cases.
The results of the microbial activity study did not present an entirely
consistent pattern. Variations due to different pesticides, soils and
pesticide-soil interactions were apparent. Webster and Terra Ceia soils both
provided an adequate substrate for the degradation of high level pesticide
applications, especially 2,4-D applications. Cecil soil, on the other hand,
proved to be poorly suited to the task of pesticide degradation.
In some cases, microbial metabolic activity was stimulated by high
level pesticide application. However, it was found that accelerated C02 pro-
duction was not necessarily indicative of pesticide degradation. Radio-
isotope tracing showed that an initial increase in C02 evolution by Webster
soil after 2,4-D application was the result of the degradation of formula-
tion chemicals, impurities or soil organic matter, not AI. A second increase
in respiration following a brief lag period was the result of 2,4-D degrada-
tion. This double peak pattern of CC>2 evolution was also characteristic of
2,4-D breakdown in Terra Ceia soil and trifluralin breakdown in Webster soil.
A.more detailed discussion of this phenomenon is presented in Ou et al. (1978).
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The following two inferences for land disposal methodology are suggested
by this research: (a) when pesticide application rates at a land disposal site
exceed normal usage by a large margin, pesticide soil mobility beyond that
normally seen should be expected; (b) for some combinations of soil and pes-
ticide, soil incorporation may be a useful disposal technique—possibly allow-
ing pesticide applications of 20,000 ^g/g of soil.
The fourth study was conducted by Matrecon, Inc., Oakland, California,
for the Environmental Protection Agency, lERL/Cincinnati, during 1976 and
1977. The objectives were to test and evaluate various types of liners over
a 1.5- and 3-year period. Variables included longevity, effectiveness, and
cost (Haxo, 1976).
The bulk of the testing was carried out at the Richmond Field Station of
the University of California, Berkeley. Five soil or admix type materials and
eight polymeric membrane materials were selected for the study on the basis
of their potential impermeability to hazardous chemicals. Soil and admix
materials included asphalt emulsion and nonwoven fabric, compacted native fine
grain soil, hydraulic asphalt concrete, modified bentonite and sand, and sealed
soil cement. Polymeric membranes included butyl rubber, chlorinated poly-
ethylene, reinforced chlorosulfonated polyethylene, elasticized polyolefin,
ethylene propylene rubber, reinforced polychloroprene, polyester, and poly-
vinyl chloride.
The six classes of waste to which the liners were exposed were acidic
sludge, alkaline sludge, cyclic hydrocarbon sludge, lead wastes from gasoline
tanks, oil refinery tank bottom waste, and pesticide sludge. An exact iden-
tification of the pesticide sludge was not available for public disclosure
at this time. However, it was a commercial herbicide waste stream commonly
handled by a local industrial disposal firm (Haxo, 1977).
Each test cell contained 28.4 liters (1 ft^) of waste, and the respective
liner materials were incorporated into the bases of the individual cells.
As demonstrated by these three research projects, the question of pesti-
cide mobility via leachate migration commands much attention once the given
chemical is deposited. For this reason, land burial is most suitable for
solid or semisolid wastes. Water solubility of the disposed material is of
primary importance. Fear of groundwater contamination and subsequent inges~
tion of toxic chemicals by humans and livestock appears warranted in light of
mishaps where this has occurred (EPA, 1975a, 1975b).
The factors capable of preventing pesticide leaching may be grouped in
three categories: soil adsorption; physical barriers; and biological degra-
dation. Frequently, all three of these are included in the design and opera-
tion of land disposal facilities.
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Soil adsorption of migrating substances is dependent on heavy soils,
particularly those containing high percentages of clay and/or organic mat-
tero Soils consisting primarily of sand will adsorb very little leachate. One
notable example of sandy soil response to pesticide application can be seen
in the study done by Young et al. (1975) on the Eglin Air Force Base Reserva-
tion, Florida, where large quantities of pesticide were applied to a small
area in the process of testing spray equipment* This study will be examined
later in the soil incorporation discussion*
Containment of substances by physical barriers toay be accomplished by
natural geology or by the addition of man-made systems. In some locales,
especially upland desert areas, surface soil is underlain by rock basins that
effectively seal off any groundwater escape. In addition, yearly precipita-
tion is less than the capability for evaporation and transpiration. Such a
site was utilized in a study by Goulding (1973) at Oregon State University
and was found to be ideal for land disposal purposes.
Most of the agricultural and industrial sources of pesticide wastes are
not located in sections of the United States where the previously stated de-
sirable geological and climatic conditions occur (Lindsey et al«, 1976). As
a result,, containment of pesticides may involve the introduction of artificial
barriers to fluid movement. Because clay is an ideal natural liner for a land-
fill, this type of soil may be hauled in and graded to the desired depth,
typically 46 cm (18 inc.) (Fields and Lindsey, 1975). One commercial instal-
lation, a leader in the field of pesticide and other hazardous waste disposal,
claims a clay soil depth approaching 24 m (80 ft) beneath its Illinois land-
fill (Roeser, 1977). As evidenced by the third abstract cited (Haxo, 1976),
many other liners are available and under study.
A more extreme type of containment utilized in some areas involves the
use of underground concrete receptacles which are closed after filling to a
desired depth and sealed with the intent of indefinite storage (Ghassemi and
Quinlivan, 1975). Similar use of mine openings, particularly old salt mines,
has been discussed in the literature (Atkins, 1972; Fields and Lindsey, 1975;
Wiles, 1976).
Encapsulation of waste pesticides in water-insoluble masses of concrete,
molten asphalt, polyurethane, or polyethylene has also been explored as a
possible means of preventing chemical migration (Fields and Lindsey, 1975;
Lubowitz and Wiles, 1976).
Biological detoxification is capable of reducing the toxicity of many
compounds in substrates if the proper microorganisms and nutrients are pres-
ents A thorough discussion of microbial degradation of pesticides and other
hazardous materials is given in Section 5 of this report.
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Soil Incorporation
The breakdown of pesticides in soil is partially the result of the physi-
cal and chemical interactions of the pesticides with the surrounding particles.
The physical portion of this interaction involves adsorption-desorption,
photolysis, and transport to sites where chemical degradation may occur* Oxida-
tion, reduction, hydrolysis, and polymerization of pesticide compounds have
all been proven or postulated in soil incorporation studies (Leonard et al.,
1976). Microbial activity also plays an important role in pesticide breakdown
when circumstances favoring the growth of the necessary organisms is present*
There are many instances of pesticide soil incorporation in the research
literature* However, these studies generally address the problems associated
with the normal use of pesticides* There are no examples of research on soil
incorporation of pesticides as a full-scale disposal technique* Three studies,
whose findings have implications for land disposal, will now be discussed.
The first study is the single most authoritative reference on biodegra-
dation of pesticides in soil (Sanborn et al., 1977)* This report examines the
pertinent literature and assesses the potential for soil disposal of 45 prom-
inent pesticides in "tonnage" quantities.
Based on persistence, toxicity, and mobility, 21 of the chemicals under
study were found to be unsuitable for land disposal* These include:
Aldrin Endosulfan Monuron
Atrazine Endrin Paraquat
Chlordane Heptachlor PGP
DDT Kepone® Picloram
Dicofol Linuron Toxaphene
Dieldrin Methyl bromide
Diquat Mirex
Diuron Monolinuron
Conversely, 10 were found to be susceptible to natural detoxification and,
hence, suitable for land disposal:
Bux® EPTC
Carbaryl Malathion
Captan Methoxychlor
Chloramben Nitralin
2,4-D Trifluralin
Finally, Sanborn and co-workers concluded that 14 of the substances under
scrutiny cannot be definitely categorized given the available data:
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Bromacil Maneb
CDAA Methyl parathion
Diazinon® Nabam
Disulfoton Parathion
Dicamba Phorate
Dodine 2,4,5-T
Guthion® Zineb
Sanborn and co-workers also noted that most of the available data de-
scribe well dispersed, low level applications of pesticides to soil. In bulk
disposal operations, long periods of persistence of the unwanted chemical or
its degradation products would be expected. For this reason, programs to mon-
itor pesticide decomposition and ensure environmental safety should accompany
any large-scale soil disposal of all pesticides.
A second study examined one of the least documented areas in pesticide
biodegradation literature, the effect of high volume pesticide application on
a land surface. These data compiled at Eglin Air Force Base, Florida, provide
some new and important information (Young, 1975).
J
The test site was a 2.6-sq km (1-sq mile) plot on which Air Force spray
equipment was tested from 1962 to 1970. During that 8-year period, 157,000 kg
(346,117 Ib) of military herbicides were deposited on the grid. The AI included
2,4-D, 2,4,5-T (some associated TCDD), picloram, and cacodylic acid. The soil
of the test site consisted of > 90% sand, < 6% clay, < 5% silt, and < 0.5%
organic matter. The water table varied from 1.8 to 3.0 m (6 to 10 ft). Five
creeks drain the spray grid and empty into Choctawhatchee Bay < 5 km (3 miles)
away. Several small ponds are also present. The average yearly precipitation,
measured from 1964 to 1969, was 1.54m (60.4 in.).
The experimental approach involved observation of variations in the
population density and species diversity of native wildlife, as weil as
analysis of chemical residues in animal tissues and soil cores. This proce-
dure allowed the researchers to quantify ecological changes taking place in
the test area after the cessation of spraying. Additional qualitative judg-
ments in regard to the health of specimens collected and observed were also
included.
Young recorded a return of plant cover and an increase in species di-
versity after the applications were concluded. No toxic or teratogenic ef-
fects were found among the organisms present on or near the grid. However,
residues of TCDD (or a chemical appearing very similar to TCDD via combined
gas chromatography/mass spectrometry) were found at levels up to 540 ppt in
liver and fat tissue from mice. This contradiction remains unexplained.
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Assays on oysters at the mouths of the creeks draining the spray area
yielded levels of 1.45 ppm arsenic. Because this finding was not substan-
tially different from levels found in oysters from other parts of Chactawatchee
Bay (1.32 ppm), Young judged this measurement to be insignificant. The gen-
eral conclusion reached was that no permanent harm was done to the spray area
during the equipment testing.
The physical characteristics of the spray grid present a possibility of
leachate migration and volatile losses. The lack of clay and organic matter
in the soil profile—combined with the high yearly rainfall, high volume sur-
face runoff, and shallow water table—suggests a clear pathway to the coast-
line for any water-soluble residues. In addition, the aerial applications
with no effort to ensure penetration into the sandy soil leave open the pos-
sibility of volatile losses. For these reasons, it would be unwise to attempt
comparisons between this study and soil incorporation of unwanted pesticides
on a land disposal site selected for maximum containment of deposited mate-
rial and managed to allow minimum losses of the waste.
A third study consisted of a series of laboratory-scale experiments (Cole
and Metcalf, 1977). Seven pesticides were introduced to model ecosystems to
enable researchers to follow the transfer of radioactively tagged residues to
land, air, and water. The pesticides were aldrin, dieldrin, pentachloronitro-
benzene, pentachlorophendl, parathion, methyl parathion, and captan. The eco-
systems consisted of 19-liter, wide-mouth glass carboys. Each contained 400 g
of vermiculite or 3,000 g of Drummer silty clay loam soil (9.5% sand, 60.2%
silt, 30.37o clay, and 7.17, organic matter). Measured amounts of water were
added and maintained to support the germination and growth of 50 corn seeds
per system.
The pesticides were applied in a manner designed to simulate normal use.
Five milligrams were injected beneath the soil beside each seed as a pre-
emergent application, and the same amount was sprayed on the foliage on the
10th day as a postemergent application. These concentrations were calculated
to represent field levels of 45.4 kg/ha (1 Ib/acre).
Also on the 10th day, a community of invertebrate organisms was added.
Five days later, a prairie vole (Microtus ochrogaster) was added to serve as
the top trophic level in the terrestrial ecosystem.
On the 20th day, all remaining plant and animal debris was removed and
the carboys were flooded with water. A microaquatic community was then added
in much the same way that the terrestrial organisms had been added. Again, the
experimental design encouraged any food chain accumulation to show itself in
a top level consumer—three small fish (Gambusia affinis).
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An examination of the radioactivity present in the ecosystems yielded the
following conclusions:
* Aldrin and dieldrin were the most persistent chemicals in the soil.
* At the termination of the terrestrial phase of the experiment, the
majority of the biocides were found in the soil and/or the air--not
in the animals»
* The presence of vegetation and organic material in soil encouraged
soil adsorption of pesticides.
* At the termination of the aquatic phase of the experiment, a much
larger quantity of all of the applied chemicals was found in the air
than was found in the watero
* The aquatic organisms accumulated the biocides from the water to a
much greater degree than did the terrestrial creatures from the air.
v
* No bioaccumulation of chemicals at the top of either food chain was
observedo (The short duration of the experiment combined with the
simplicity of these ecosystems places limitations on this conclusion.)
Admittedly, this experiment is designed to demonstrate chemical mobility
under normal use, not under the high loading common in land disposal. Another
problem encountered in an analysis of these data is the unknown percentage of
hontoxic breakdown products included in the radioactivity measurements. However,
the results do raise several questions for those interested in land disposal
methods:
* What percentages of pesticides are translocated from the land disposal
site to air, soil, and water under normal burial procedures?
The work by Cole and Metcalf (1977) suggests that for their test pes-
ticides, soil and air would contain the highest levels. The individual
chemical's characteristics, the nature of the receiving soil, and the
depth of cover would determine the exact proportion that would be
found in eacho Surface water would be expected to contain only a frac-
tion of the total.
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* Is the possibility of air pollution from pesticides adequately met in
landfill design?
Even though most current land disposal evaluations are devoted to leach-
ate containment rather than to volatile losses, the research under dis-
cussion here implies that the latter may account for the fate of a sig-
nificant share of deposited pesticides. Again, this comment must be
qualified with consideration of the individual pesticide's characteris-
tics, the nature of the receiving soil, and the depth of cover employed•
POTENTIAL IMPACTS
On the basis of available information, land disposal will be discussed
in terms of potential environmental and economic cost impacts.
Potential Environmental Impacts
Land disposal of pesticides requires safeguards to prevent injury to soil,
water and air, as well as direct harm to various forms of life. The lack of
treatment, which is characteristic of land disposal, presents the possibility
of releasing the given AI into the environment. Because the environmental
problems associated with the different types of land disposal are very similar,
the discussion of hazards will refer to specific methods only where such a
reference is appropriate.
Contamination of soil is to be expected in the immediate vicinity of pes-
ticide land disposal activities. Consideration of the problems presented by
accidental spills and leaky or broken containers requires the recognition of
this fact. Site selection must involve a judgment on the present and future
potential use of the land in question. It is essential that the property be
isolated from populated areas, tillable land, livestock, and both surface
water and groundwater.
Land adjacent to land disposal operations may also be subjected to an
accumulation of pesticide residues. Care must be exercised in the use of land
parallel to the roadways traveled by waste haulers due to the possibility of
accidents. Problems can also occur if seepage of leachate appears at lower
elevations from a disposal site. Discarded dry formulations may become wind°
borne pollutants. Because of similar hazards, spraying unused pesticides or
tank rinsing solutions on the soil surface should take place only after care-
ful consideration of the wind speed and direction. These possible environmen-
tal problems may be minimized if adequate caution is exercised by the disposal
site personnel and if there is a generous buffer zone surrounding the princi-
pal areas of disposal activity.
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Both surface water and groundwater are vulnerable to contamination from
nearby pesticide land disposal. Leaching of the deposited chemicals is the
most significant hazard. In the design of landfills and infiltration/
evaporation basins, impermeable liners offer the most promising -solution to
this problem (Fields and Lindsey, 1975). Tiling a burial site may provide
another alternative. With such a system, regular sampling of the water per-
colating through the subsoil is possible. If necessary, the leachate may be
retained for treatment prior to discharge. The possibility of water contam-
ination is also very dependent on the location and surface drainage of the
operation. The site should be located above the 100-year floodplain and
situated so that natural precipitation and runoff will not wash wastes into
nearby waterways.
Land disposal procedures may also contaminate the air. The evaporation
of waste compounds and their potential photolytic and biochemical degradation
products is an integral part of soil incorporation and infiltration/evaporation
disposal. For this reason, the chemical nature of a waste must be considered
before implementing these methods. Formulations known to be volatile or to form
toxic gases should be handled in some other way.
|
Other land disposal methods should allow only minimal air contact with
the waste to prevent volatile losses. Burial should proceed rapidly with
adequate cover to ensure containment. Spills should be covered immediately.
Toxic powders may be dispersed in the air during the unloading of dry formu-
lations at a landfill site. Settling dust with applications of water, com-
bined with caution on the part of drivers and employees while operating
vehicles in the area designated for wettable powders, will control this prob-
lem.
If pesticide wastes are not properly contained during land disposal pro-
cedures, adverse consequences are likely for living organisms. The potential
avenues for harm include direct bodily contact, ingestion, inhalation, or the
destruction of normal habitat and food sources. The misplaced compounds may
harm nontarget species, including man, or initiate a series of deleterious
alterations in a local ecosystem. Many incidents of accidental pesticide
poisoning of humans and livestock appear in the literature (Environmental
Protection Agency, 1975a, 1975b). Reduction of nontarget earthworms and the
host of other invertebrates which inhabit soil is another example of damage.
These seemingly insignificant creatures populate normal soil in great num-
bers and serve to transform vegetation litter into humus. The ultimate effect
of their decline is a loss in natural fertility and an increased demand for
fertilizer in agricultural areas. Similarly, decreases in natural predator
populations due to incidental poisoning will also increase the dependence of
cultivated soils on chemicals, in this case additional pesticides (Edwards
and Thompson, 1973).
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Potential Economic Impacts
Of the various pesticide land disposal methods under discussion, reason-
ably complete economic data can be found in the literature only for burial in
a hazardous waste landfill. User gate fees at the California Class 1 sites
range from $3.85 to $9.35/MT ($3.50 to $8.50/ton). Charges per volume at the
same locations ranged from $2.30 to $13.75/cu m ($1.75 to $10o50/cu yard)
(Ghassemi and Quinlivan, 1975). Miscellaneous additional fees are also charged
in the form of annual registration fees, specific permits, and special handling
fees.
The Big Blue Hills disposal site located near Coalinga, California, in
Fresno County required an initial investment of $12,711 in 1973 including:
Land
Trench excavation
Fencing
Safety equipment
Access road, signs,
incidentals
Total $12,711
(Ghassemi and Quinlivan, 1975)
Operating cost for fiscal year 1974 to 1975 was approximately $16/MT ($14/ton)
(Ghassemi and Quinlivan, 1975).
This site was judged to be well suited to serve as an example for this
discussion. The waste handled is almost entirely composed of pesticides and
their containers. The quantity of waste processed makes the Big Blue Hills
operation the biggest pesticide disposal facility in California, handling
380 MT (425 tons)—57% of the total pesticide waste recorded via the
California Waste Hauler manifest system during the first half of 1976
(California Department of Health, 1975).
FUTURE RESEARCH NEEDS
Land disposal procedures have been widely employed because they are eco-
nomical and appear uncomplicated. However, they do not actively cause the
detoxification of the unwanted chemical. This fact presents the possibility
of adverse environmental impactSo The severity of these potential hazards re-
mains difficult to assess because of sizable data gapso The majority of
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pesticides-have not been examined to determine their fate via land -disposal.
Leaching and volatile losses from unlined disposal sites or evaporation/
infiltration ponds cannot be predicted with any certainty. The capacity of
various soils to adsorb, retain, and degrade pesticides has not been adequately
quantifiedo
The establishment of new disposal sites for hazardous chemicals is be-
coming increasingly difficult because of adverse public opinion and the gen-
eral increase in land values. The selection of land that is geologically suit-
anle, the segregation of pesticide wastes from other refuse, and the need to
monitor the disposal site, all require careful attention. The possibility of
future legislation increasing the requirements for environmental safeguards
or prohibiting land disposal of some compounds in favor of physical-chemical
treatment remains open.
After reviewing the literature, there are four areas which call for addi-
tional comment.
* First, there is an inadequate data base available to predict what
happens when a pesticide is land disposed. The rate of breakdown and
the formation of water-soluble or volatile breakdown products are
often uncertain« Further work is needed to provide a more scientific
basis to land disposal of pesticides.
* Second, the use of sample wells in and around land disposal opera-
tions should be expanded. Available information suggests that move-
ment of contaminants in groundwater may be very slow. In instances
where the detection of potential problems is too slow, large amounts
of underground water as well as the health of nearby persons and
livestock may be needlessly endangered.
* Third, current research on impermeable liners for land disposal facili-
ties should be continued, and the installation of appropriate liners
at new sites should be encouraged.
* Fourth, volatile losses from land disposal operations remain largely
undetermined. Tests should be undertaken to establish the hazards
related to vapors and gases escaping from land disposal facilities.
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REFERENCES
Atkins, P. R. The Pesticide Manufacturing Industry - Current Waste Treatment
and Disposal Practices. PB 211 129, 1972.
California Department of Health, Berkeley. Hazardous Waste Management: Law,
Regulations, and Guidelines for the Handling of Hazardous Waste, 1975.
California Assembly Bill No. 598. Hazardous Waste Control, State of California
Statutes of 1973, 1:2387-2393.
Cole, L. K. and R. L. Metcalf. Distribution of Pesticides and Their Deriva=
tives in the Soil, Air, Water, and Biota of Physical Model Ecosystemso
Presented at the Annual Air Pollution Control Association Conference, 1977 9
Davidson, J. M., G. H. Brusewitz, D. R. Baker, and A. L. Woods Use of Soil
Parameters for Describing Pesticide Movement Through Soils. Project No.
R-860364. National Environmental Research Center, Office of Research and De-
velopment. EPA-660/2-75-009, 1975.
Davidson, J. M., L* T.Ou, and P. S. C. Rao. Adsorption, Movement, and
Biological Degradation of High Concentrations of Selected Pesticides in
Soils. Presented at the 4th Annual Research Symposium on Land Disposal of
Hazardous Wastes, San Antonio, Texas, March 6 to 8, 1978. To be published
in proceedings of same.
Edwards, C. A. and A. Ro Thompson. Pesticides and the Soil Fauna« Residue
Reviews, 45:1-79, 1973.
EPA. Hazardous Waste Disposal Damage Reports. Publication No<> SW=l51s 1975a«.
EPA. Hazardous Waste Disposal Damage Reports. Publication No. SW-151.2, 1975b»
Fields, T., Jr. and A. W. Lindsey. Landfill Disposal of Hazardous Wastes -
A Review of Literature and Known Approaches. EPA Publication No. SW-165,
1975.
Ghassemi, M. and S. Quinlivan. A Study of Selected Landfills Designed As
Pesticide Disposal Sites. EPA Publication No. SW-114c, 1975»
174
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Goulding, R. Le> Waste Pesticide Management - Final Narrative Report. EPA
Demonstration Grant 5-G06-EC-00222, 1973.
Haxos Ho E«s Jr» Evaluation of Liners When Exposed to Hazardous Wastes. Resid-
ual Management by Land Disposal. In: Proceedings of the Hazardous Waste Re-
search Symposium, EPA Report No0 600/9-76-015, 1976.
Haxo, E» E«, Jr. Matrecon, Inc., Oakland, California. Personal communication
to F. Hopkins, Augo 25, 1977o
Klein, S. Ao, Do Jenkins, and J. W. Biggar. An Evaluation of the Accumula-
tion, Translocation, and Degradation of Pesticides at Land Wastewater
Disposal Sites. Prepared for the Army Medical Research and Development
Command, AD/A-006-551, 1974.
Leonard, R0 Ao, G. W0 Bailey, R. R. Swank. Transport, Detoxification, Fate,
and Effects of Pesticides in Soil and Water Environments. Land Application
of Waste Materialso Soil Conservation Society of America, Ankeny, Iowa,
U976. ppo 48-780
l
Lindsey, A. We, D. Farb, and W0 Sanjour. OSWMP Chemical Waste Landfill and
Related Projects. Residual Management by Land Disposal - Proceedings of the
Hazardous Waste Research Symposium. EPA Report No. 600/9-76-015, 1976.
Lubowitz, H. R. and Co Co Wileso A Polymeric Cementing and Encapsulating
Process for Managing Hazardous Waste. Residual Management by Land Disposal -
Proceedings of the Hazardous Waste Research Symposium. EPA Report No. 600/9-
76-015, 1976.
Ou9 Lo To, Do Fo Rothwell, Wo B. Wheeler, and J. M. Davidson. The Effect of
High 2,4-D Concentrations on Degradation and Carbon Dioxide Evolution in
Soils. J0 of Environ. Qual., 7(2):241-246, 1978.
Roeser, P. Earthline Division SCA Services, Wilsonville, Illinois. Personal
communication to Fo Hopkins, Aug. 1, 1977.
Sanborn, J. R., B0 Mo Francis, R. L. Metcalf. The Degradation of Selected
Pesticides in Soil; A Review of the Published Literature. Prepared by the
Illinois Natural History Survey for the Municipal Environmental Research
Laboratory Office of Research and Development. EPA-600/9-77-022, 1977.
Stephens, R. Do California Department of Health, Vector and Waste Management
Section. Personal communication to R. Wilkinson, Sept. 26, 1977.
Storm, Do L0 and Eo Margitan. Survey of Operational Procedures at Class 1
Hazardous Waste Disposal Sites in California. California Vector Views,
22(2):9-18, 1975.
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Wiles, C. C. An Evaluation of Storing Nonradioactive Hazardous Waste in
Mine Openings. Residual Management by Land Disposal - Proceedings of the
Hazardous Waste Research Symposium. EPA Report No. 600/9-76-015, 1976.
Young, A. L., C. E. Thalken, and W. E. Ward. Studies of the Ecological
Impact of Repetitive Aerial Applications of Herbicides on the Ecosystem
of Test Area C-52A, Eglin AFB, Florida. Prepared for Air Force Armament
Laboratory, Report No. AFATL-TR-75-142, 1975.
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SECTION 8
ALTERNATIVES TO PESTICIDE DISPOSAL
INTRODUCTION
This section discusses various alternatives to pesticide disposal/
detoxification with special emphasis on two chemical conversion methods:
chlorolysis and hydrodechlorination. Technical details of each process with
potential environmental and economic cost impacts are given. The section
, closes with a discussion of future research needs.
y •
ALTERNATIVE METHODS
Alternatives to pesticide disposal/detoxification procedures include:
normal use, return to manufacturer or supplier, export, reprocessing to re-
cover original material, and conversion to other chemical forms having eco-
nomic valueo The first three alternatives lie outside the scope of work. The
two remaining alternatives are potentially useful and consistent with re-
source recovery goals.
By reprocessing we mean physical treatment to recover the economic value
of AI(s) or admix materials (e.g«, solvents, diluents, emulsifiers, etc.).
Such physical treatments may include: solvent or aqueous extraction, simple
or fractional distillation at atmospheric pressure or under partial vacuum,
drying or dewatering, etc. By conversion, we mean application of chemical
treatment to recover economic value of the pesticide by producing other chemi-
cals for sale or use«
Reprocessing methods are of potential utility in handling quantities of
unwanted, cancelleds or otherwise restricted pesticide Al's and finished
formulations. Reprocessing is occasionally done by the pesticide industry
during normal manufacturing and formulating operations (e.g., reworking to
meet specifications), but it has been seldom applied to finished formula-
tions already released to the marketing and distribution systems. Economic
and legal incentives are lacking. Further, reprocessing has no potential as
an alternate to field disposal of pesticide products by the layperson. It is
potentially more useful to the pesticide industry.
177
-------
Conversion methods by chemical treatment may be applied at either level
of the marketing distribution system but have not been utilized. Little use has
been made of either reprocessing or conversion technology to date as alterna-
tives to disposal/detoxification procedures*
SELECTED CHEMICAL CONVERSION METHODS
Two selected conversion methods for transforming unwanted pesticides into
useful chemicals are chlorolysis and catalytic hydrodechlorination. These are
discussed below*
Chlorolysis
Exhaustive chlorination as a method of disposing of pesticides and other
chemical wastes has been suggested at least since 1974* (Anon* 1974)* Two U»S.
patents describing basic improvements in chlorination appeared in 1972
Krekeler et al., i972a; 1972b). A recent study for the EPA—Industrial En-
vironmental Research Laboratory, Research Triangle Park has assessed the
potential usefulness and economics of chlorolysis to destroy pesticides and
other chlorohydrocarbon wastes (Shiver, 1976)* A follow-up report, including
process details, engineering cost estimates, and marketing information is
currently (May 1978) being printed and the Summary portion of the report will
be available through National Technical Information Service (NTIS) (Des Rosiers,
1978).
Exhaustive chlorination can be performed over a range of pressures and
temperatures, depending on the type of feed stock (aliphatic or aromatic).
According to a new process developed by Farbwerke Hoechst Ag, Frankfurt/Main,
Germany, hydrocarbons and their oxygenated or chlorinated derivatives are
completely converted to carbon tetrachloride, phosgene, and hydrogen chloride
at pressures up to 24 MPa (240 atm) and temperatures up to 620°C (1148°F)
(Krekeler et al. 1975). Figure 30 presents a schematic flow diagram of the
Hoechst AG chlorolysis process.
Three typical reactions are possible depending on the type of hydrocar-
bon involved:
178
-------
Hazardous
Waste
Materials
VO
24MPa max.
620°C max.
Q Q
-10°C
186°C
O'C
HCI
CI2
COCI2
CCI.
C2C]6
2.2
MPa
HCI
CI2
COCI2
CCI4
243°C
35°C
I
2.2M
Pa
HCI
C<$CI,
222"C
CI2
80°C
2.1M
Pa
115°C
CCI4
0.1M
Pa
NaOH
I
80°C
ecu
Waste
"Water
Reactor
High Boiler
Column
Crude CCI4
Column
HCI
Column
Pure CCI4
Column
Caustic Scrubber
Separator
Dryer
Source: Adapted from Krekeler et al. (1975).
Figure 30. Schematic diagram of the Hoechst AG chlorolysis process.
-------
Cl
RGB: Cl
DDT
2,4,5-T:Cl
CClj +
CC14 + HC1
-GH2-C-OH + C12 —*-CCl4 + HCl + COC12
Pesticides and organic wastes that contain sulfur, nitrogen, or phos-
phorus may have adverse effects on the chlorolysis process. Thus, the pres-
ence of sulfur-bearing pesticides in excess of 25 ppm sulfur in the hydro-
carbon feed stream may cause severe corrosion of the nickel tube catalytic
reactor (Shiver, 1976). There is some question as to whether nitrogen tri-
chloride and phosphorus trichloride or phosphorus pentachloride would be
formed in applying the chlorolysis process to nitrogen- and phosphorus-
containing pesticides and of the hazards if these products were formed.
More than 550 individual pesticide Al's have been sold commercially in
the United States in recent years. Perhaps 200 of these have been produced in
volumes of & 500 MT (& 1 million pounds) annually. Of the 200 Al's, 30 con-
tain combinations of the elements C, H, Cl, and 0. The remaining pesticides
contain additional elements such as N, S, and P in various combinations with
the elements previously listed.
The 30 pesticides which are the most appropriate candidates for chlo-
rolysis include highly chlorinated hydrocarbons, those based on diene-
structures, and other agricultural chemicals, principally fumigantso The
highly chlorinated hydrocarbons include:
Toxaphene
DDT
2,4-D (acid and esters)
2,4,5-T
Pentachlorophenol
Trichlorophenols
Dichloropropene
Dibromochloropropane (DBCP)
TCA, sodium salt
Dalapon
Silvex
Dicamba
Dicofol
Methoxychlor
DCPA
Endothall
Lindane
Benzene hexachloride
TIBA (2,3,5-Triiodobenzoic acid)
180
-------
Diene-based compounds:
Ghlordane
Aldrih
Endrin
Heptachlor
Other agricultural chemicals:
Methyl bromide
Methyl chloride
Ethylene di chloride
£»Dichlorobenzene
ja-Dichlorobenzene
Perthane® }
TCBG - Trichlorobenzyl chloride
, Other types of pesticides containing phosphorus, nitrogen, sulfur, or
'toxic metals may not be appropriate for chloro lysis. On the basis of limited
demonstrations of chlorolysls, we can only indicate potential application to
(pesticides. Recently cancelled or greatly restricted pesticides are those
which are highly chlorinated and those based on diene- structures. Fortunately,
these may be the best candidates for chlorolysis.
Catalytic Hydrodechlorination
Workers at Worcester Polytechnic Institute have researched the potential
for detoxification of polychlorinated chemicals, including pesticides (e.g.,
DDT, aldrin, dieldrin, and toxaphene) and polychlorinated biphenyl materials
(PCB's), by reaction with high pressure hydrogen gas in the presence of a
catalyst (LaPierre, et al«, 1977). Thus,
RCln + xH2 > RHxCln_x + xHGl
where n and x are small integerso
The rationale behind this procedure is that partially dechlorinated or
nonchlorinated molecular species may be less toxic and more readily bio-
degraded than highly chlorinated compounds. Chlorinated pesticides which are
capable of being completely converted to hydrocarbons may be useful as fuels,
chemical intermediates, or solvents.
Figure 31 presents a schematic flow diagram of the hydrodechlorination
process adapted for batch operation. A large scale reactor has not been
181
-------
ETHANOL LIQUID
CONDENSER
CONDENSER
SOLVENT
HOLDING
TANK
HIGH PRESSURE
HYDROGEN
NaOH IN
ETHANOL
SOLUTION
ROTATING
DRUM
EXTRACTOR
JXTENDERS 130UOS
"^ FILTER
PUMP
CAT. RETAINER
HYDROCARBONS
PRODUCT
STORAGE
Source: Kranich et al. (1977).
SOLVENT
RECOVERY
STILL
HYDROCARBONS
+ NaCI
(+ H20)
LIQUID
LIQUID
EXTRACTOR
NaCI
Figure 31. Schematic flow diagram for hydrodechlorination process.
182
-------
designeds and the figure represents current technology based on laboratory
scale experiments (Kranich et alo, 1977).
Polychlorinated compounds (including finished pesticide formulations) are
charged as a batch to a rotary (tumbling) extractor. Extraction takes place
in hot ethanol, and the extracted material is pumped to the reactor vessel.
Alcoholic caustic (sodium hydroxide) is then added. The function of the
caustic is to react with liberated hydrogen chloride gas which can deactivate
the catalyst and also lead to corrosion problems. Next, the reaction vessel
is pressured to 3 to 5 MPa (30 to 50 atm) with hydrogen gas.
The prefered catalyst is 61% nickel on kieselguhr, although 10% palladium
on charcoal is equally effective. For best results, the catalyst is prereduced
in hydrogen at 370° c (698°F). Catalyst particles of 0.15 to 0.30 cm diameter
are readily retained on a (698°F) stainless steel screen during reactor vessel
dischargingo The quantity of catalyst required is 0.2% of the weight of the
compound to be dechlorinatedo
Reaction conditions for hydrodechlorination vary depending on the poly-
chlorinated compound to be detoxified. However, experimentally determined
conditions for pressure and temperature have been defined: 3 to 5 MPa (30 to
50 atm) and 100 to 120°C (212 to 248°F). Reaction times depend on the desired
degree of dechlorination for a particular compound. Figure 32 indicates that
85 to 90% of the chlorine may be removed from DDE, toxaphene, and PCB's in
about 5 hr (Kranich et alo, 1977).
In order to remove chlorine completely from aldrin, dieldrin, and toxa-
phene, it is necessary to utilize pressures a 5 MPa (* 50 atm) and tempera-
tures exceeding 130°C (266°F)o These sets of conditions may cause rapid loss
of catalyst activity«
After reaction is complete, or the desired degree of dechlorination has
been achieved as evidenced by a decreasing demand for caustic, the reaction
mixture is pumped to a solvent recovery still. The catalyst particles are
retained on a stainless steel screen in the reactor vessel. Ethanol is dis-
tilled through a fractionating head, e<>g., bubble cap column, and subsequently
returned to the solvent holding tank.
The resulting hydrocarbons and possibly some incompletely dechlorinated
materials together with salt and small amounts of water introduced from the
feed material are washed with water in a liquid-liquid extraction device. The
salt water is discarded, and the hydrocarbon materials are stored for possible
alternate uses.
Engineering specifications and exact design features have not been de-
velopedo The process has not been advanced beyond the laboratory scale, but
183
-------
1.0
0.8
c
o
o
•| 0.6
o
"5
c
*o» 0.4
6
c
o
Z 0.2
o
o
ODE
0
TOXAPHENE
PCB
5 10 15
Reaction Time, Mrs.
20
Source: Kranich et al.
(1977).
Figure 32. Experimental reaction process for three
chlorinated hazardous materials.
184
-------
an executive summary of the hydrodecKl'orination process is available (Ebon,
1977)0
POTENTIAL IMPACTS
The potential environmental and economic impacts of chlorolysis and cata-
lytic hydrodechlorination as potential alternatives for the disposal of un-
wanted pesticides are surveyed here.
Potential Environmental Impacts
Chlorolysis of certain types of pesticides and other hazardous chemicals
and wastes yields carbon tetrachloride, phosgene, and hydrogen chloride. Con-
trol of potential gas and liquid effluents from a large-scale chlorolysis unit
is easily achievable through low temperature distillation units, condensers,
traps, scrubbers, absorbers, etco The experience gained by Farbwerke Hoechst
AG of Germany will be utilized if a chlorolysis unit to treat organochlorine
wastes and other hazardous materials is constructed and operated (Des Rosiers,
1977)o Chlorolysis units operating successfully include one in Frankfurt/Main,
Germanys and two in Soviet Russia.
An environmental impact statement for a chlorolysis plant has not been
formally developed but would be part of the overall assessment necessary
prior to construction* The principal environmental factors to be considered
include shipment and handling of hazardous organochlorine wastes prior to
chlorolysis, control of potential gas and liquid effluents after conversion,
and handling and storage of the final products. Current technology ensures a
minimum probability of harmful emissions occurring. There is every reason to
believe a large~scale chlorolysis unit could effectively operate to convert
unwanted pesticides in an environmentally acceptable manner.
We are aware of certain incidents regarding the sudden occurrence of
carbon tetrachloride in rivers and municipal drinking water supplies. These
events have been traceable to illegal and indiscriminate release of the chemi-
cal to the Kanawha and Ohio rivers in February 1977 and to the earlier dis-
covery of small quantities of many organic chemicals, including carbon tetra-
chloride, in the drinking water of New Orleans in 1974 (Marx, 1977). The most
recent example of carbon tetrachloride in drinking water is its unintentional
release as a contaminant in chlorine gas used to disinfect water in Philadelphia
(Toxic Materials News, 1977). Knowledge of these situations serves notice as
potential environmental dangers when considering the construction and operation
of a chlorolysis facility to treat hazardous waste materials.
Phosgene waste generally occurs as a contaminant in gaseous vent streams.
Proper waste management options include: hydrolysis with steam followed by
185
-------
sodium carbonate solution scrubbing; sodium hydroxide or ammonia solution
scrubbing in a packed tower; or reaction with alcohols to form chloroformates
and subsequently polycarbonates (Ottinger et al., 1973).
No environmental impact statement has been developed for the hydrode-
chlorination process* However, hydrodechlorination appears technologically
feasible in large scale and probably can be performed without harm to the
environment. It utilizes hydrogen gas at elevated pressures which requires
care but is a standardized industrial procedure* The waste stream will con-
tain hydrocarbons, perhaps partially dechlorinated species, and salt* The
hydrocarbon and other organic species must be separated from the waste stream
by liquid-liquid extraction and ultimately disposed, such as incineration, or
utilized as chemicals or solvents elsewhere.
Finally, we note that hydrodechlorination and chlorolysis are related
and one process can be thought of as the converse of the other:
Chlorocarbons + Cl, catalyst
(pesticides) A CCV HC1 + COC12
Chlorolysis
Chlorocarbons + H catalyst ^ Hydrocarbons + HC1
(pesticides) A (or partially
dechlorinated
' species)
Hydrodechlorination
In one process, a useful solvent, an acid, and a chemical intermediate are
formed. In the other process, an acid and hydrocarbons or other chemical
species of potential use as chemical intermediates or as fuel are produced.
The environmental impacts of both procedures need to be addressed.
Potential Economic Impacts
At least onr cost estimate for a chlorolysis plant has been made
(Samfield, 1978). A plant with a capacity to process 25,000 Mr/year of waste
hydrocarbons or chlorohydrocarbons could yield approximately 15% discounted
cash flow rate of return on investment at a disposal cost of approximately
$133/MT. Operating and financial data are estimated in Table 24*
The capital investment for primary and auxiliary facilities may be as
high as approximately $27 million for a plant processing 25,000 Mr/year of
organochlorine waste* The cost to destroy chlorohydrocarbons may be $0.13/kg
186
-------
TABLE 24. OPERATING AND FINANCIAL DATA FOR A CHLOROLYSIS FACILITY
PROCESSING 25,000 MT/YR OF ORGANOCHLORINE WASTE
Category
Quantity
Process data
Chlorine gas consumption
Carbon tetrachloride produced
Hydrogen chlorine produced
Reactor temperature
Reactor pressure
Cost data
Depreciable investment
Working capital
Annual operating cost, including royalty
Revenue from CCl4 and HCl
Unit disposal cost at 15% discounted
cash flow rate of return (DCFRR)
93,800 MT/yr
88,500 MT/yr
30,000 MT/yr
600°C
200 atm.
$27,210,000
4,708,000
19,881,000
28,050,000
$133.59/MT
Source: Samfield (1978).
Assumptions:
Location - Gulf Coast area.
CCl4 selling price - $300/MT.
HCl selling price - $50/MT.
Depreciation - 10 yr straightline.
Income tax rate - 50%.
Feedstock - vinyl chloride monomer wastes.
187
-------
($0.061/lb) assuming the present market price of $300/MT for carbon tetra-
chloride is upheld (Samfield, 1978).
An EPA document detailing economic analysis for the chlorolysis process
will soon be available. Utilizing the most current production data (1975) for
carbon tetrachloride, a chlorolysis unit may be capable of adding an additional
12% or 83,000 MT (91,000 tons) of carbon tetrachloride to the current estimated
capacity of 670,000 MT (740,000 tons) to give a total capacity of 750,000 MT
(830,000 tons). However, production of carbon tetrachloride accounted for an
estimated 70% of capacity in 1975 (Chemical Marketing Reporter, 1975). Thus,
any additional capacity is probably unnecessary and new production would be
hard-pressed to penetrate the carbon tetrachloride market unless it possessed
a price advantage.
Furthermore, about 90 to 95% of all carbon tetrachloride produced is
utilized in the manufacture of F-ll and F-12 for use as refrigerants and
aerosols. The future markets of these two chlorofluorocarbons are uncertain
because of the chlorofluorocarbon/ozone depletion controversy.
Thus, potential growth and even maintenance of the carbon tetrachloride
market is questionable. Pricing strategies and operating costs may eventually
be the dominant issues that determine which manufacturers and processes are
economically viable in a declining future market.
Regarding the proposed hydrodechlorination conversion process, there are
no economic data available to permit an economic assessment. It is clear, how-
ever, that hydrocarbons produced by this potential method would be far more
expensive as fuel oil than commercial sources. The economic assessment and
implications of commercialization of the hydrodechlorination must await de-
velopment of engineering cost estimates.
Future Research Needs
Farbwerke Hoechst AG, Frankfurt/Main, Germany, operates a 50,000 MT/year
reactor which exhaustively chlorinates still-bottom residues from some of its
aliphatic chemical manufacturing operations. The resulting carbon tetrachlo-
ride is utilized internally. Two large chlorolysis reactors for conversion of
still-bottom residues have been sent to the Soviet Union (Des Hosiers, 1977).
Chlorolysis for disposal of some classes of pesticides appears to be a
feasible method. It is underdeveloped and underutilized at present. Environ-
mental and economic impacts must be further developed*
The theoretical basis and laboratory feasibility for the hydrodechlori-
nation process have been established. Developments beyond this stage, i.e.,
pilot plant scale, have not been accomplished.
188
-------
Other classes of pesticides have not been examined for potential detoxi-
fication by hydrogenation. Specific candidates may be limited to chlorinated
and/or olefinic materials. Organometallic pesticides probably should not be
hydrogehated because highly dangerous hydrides may form, e.g., arsine gas.
On the basis of successful laboratory demonstrations, it is clear that
a second phase of developmental work needs to be undertaken before final
assessment of the hydrodechlorination process can be made. The data base needs
to be expanded and extended to other kinds of .pesticides. The environmental
desirability or acceptability of discarding partially dechlorinated hydrocar-
bon species as well as economic impacts have not been assessed.
189
-------
REFERENCES
Anon. Environmental Science and Technology, 8(1):19 (1974).
Chemical Marketing Reporter, June 2, 1975. p. 9.
Des Rosiers, P. Industrial Pollution Control Division, Office of Research and
Development, Environmental Protection Agency, Washington. Personal communica-
tion to R. Wilkinson, Dec. 14, 1977 and May 8, 1978.
Ebon Research Systems. Catalytic Hydrodechlorination of Polychlorinated
Pesticides and Related Substances—An Executive Summary. EPA-600/8-77-013,
Sept. 1977. '
Kranich, W. L., R. B. LaPierre, and A. H. Weiss. Process for Catalytic
Hydrodechlorination of Polychlorinated Hydrocarbons. Presented at the
American Chemical Society Division of Pesticide Chemistry. 194th National
Meeting, Chicago, Illinois, Aug. 30, 1977.
Krekeler, H., H. Meident, W. RietnenSchneider, and L. H. Hornig. U.S. Patents
3,651,157 (March 21, 1972) and 3,676,508 (July 11, 1972).
Krekeler, H., H. Schmitz, and D. Rebhan. The High-Pressure Chlorolysis of
Hydrocarbons to Carbon Tetrachloride. Paper presented at the National Con-
ference on the Management and Disposal of Residues for the Treatment of In-
dustrial Wastewaters, Washington, D.C., Feb. 3-5, 1975.
LaPierre, R. B., E. Biron, D. Wu, L. Guczi, and W. L. Kranich. Catalytic Con-
version of Hazardous and Toxic Chemicals: Catalytic Hydrodechlorination of
Polychlorinated Pesticides and Related Substances. PB-262 804, 1977.
Marx, J. L. Drinking Water: Getting Rid of the Carbon Tetrachloride,
Science, 196, 632-636 (1977).
Ottinger, R. S., J. L. Blumenthal, D. F. Dal Porto, G. I. Gruber, M. J.
Santy, and C. C. Shih. PB-224590. Aug. 1973.
Samfield, M. Industrial Environmental Research Laboratory, Environmental Pro-
tection Agency, Research Triangle Park, North Carolina. Personal communica-
tion to R. Wilkinson, June 28, 1978.
Shiver, J. K. Converting Chlorohydrocarbon wastes by Chlorolysis, Environ-
mental Protection Agency, PB 259 935, Oct. 1976.
Toxic Materials News, Nov. 23, 1977. p. 267.
190
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SECTION 9
DISCUSSION
INTRODUCTION
This section of the report presents an overview of recent research on
various pesticide disposal or conversion methods from technical, environmen-
tal, and economic viewpoints° These methods are rank-ordered according to
potential large«=scale application. Significant technical information gaps and
potential pesticide disposal problems are noted. Of particular importance is
I the identification and evaluation of those disposal procedures and safety
i precautions that are suitable for use by the layperson and those that are
more suitable for handling relatively large quantities of unwanted pesticides
by trained personnel in well-equipped facilities; e.g., by a government agency.
The section closes with a discussion of new directions for disposal research
and development appropriate to the objectives of the EPA.
OVERVIEW OF PESTICIDE DISPOSAL AND CONVERSION METHODS
Table 25 indicates those pesticides and disposal and conversion methods
which have been investigated and discussed in the previous major sections of
the report. The pesticide classification system contained in Table 25 is
based on: (a) common dominant functional groups which determine decomposi-
tion chemistry, and (b) considerations of toxicity. Further details and the
rationale for development of this particular pesticide classification system
may be found by consulting Lawless et al. (1975).
Most R&D on pesticide disposal has focused on incineration of chlorinated
hydrocarbonso There have been at least seven in-depth incineration studies of
DDT, two of Herbicide Orange, and two studies of chlorinated hydrocarbon
wastes. The latter two studies were not concerned with pesticides per se, but
the information gained was directly applicable to the destruction of chlori-
nated hydrocarbon pesticides. Some incineration studies have concentrated on
the chlorinated "dienes" (e.go, aldrin, chlordane, Kepone® ) class of com-
pounds because of concern over these environmentally persistent materials and
the Kepone® tragedy in Hopewell, Virginia, in 1976.
191
-------
TABLE 25. SYNOPSIS OF PESTICIDE DISPOSAL AND CONVERSION RESEARCH METHODS
Tachnlaue
Disposal net hod »
Incineration
Biological
treatment
Microwave
plasma
Photolysis
Activated carbon
and re a in
adsorption
Inorganic and Phosphorus- Nitrogen-
oesticides oestlcldes pesticide*
recommended Malathion Captin,
Plcloran,
^tineb
Cyanophoa,
DiazlnorfS,
Dursban®, EPNS,
Fenltrothlon,
Methyl parathion,
Paraoxon, Para-
thion, Trlazophos
Phenyl mercuric Malathion
acetate
Fenitrothion , Ametryne , Aral-
Bromacll , Car-
baryl, Monuron,
pham, Trif luralln
-
Organic
Halogen- Sulfur- Botanical and pesticides.
containing containing microbiological not elsewhere
oeaticldes Dcsticidas oeotlcides classified
A Idr in , Ch 1 or -
dane, 2,4-D,
DOT, Die Idr In.
Herbicide Orange,
Kepone®, Llndane,
Mlrex. 2.4,5-T,
Toxaphene
2,4-D, 2,4. 5-T.
HCB, PCP,
p-Dichlorobenzene
KeponeS, Methyl
bromide, PCB's
Aldrln, AmLben^,
2,4-D, DDT,
Die Idr In,
chlor , Isodr In,
PCP, TCDD
End rin, - -
Heptachlor
Hydrolysis
Conversion methods
Chlorolysis
Hydrodechlorinatlon
DDVP, Dlazlnon^, Atrazine,
Cuthlon'1^, Mala- Cap tan,
thion, Methyl Carbaryl,
purntMfm, Propoxur
Nalcd, Parathion,
TEPP
Molten salt
baths
Ozonation/
ultraviolet
irradiation
Met air
oxidation
Catalysis
Land disposal
Malathion,
Malathion/DDT
mixture
Malathion
_
,
Dtazinon'^,
Malathion,
Methyl parachion.
Parathion
Carbaryl
Propoxur ,
Vapaa®
Atrazine
Captan, Car-
baryl, EPTC,
Fluoneturon,
Metalkamate,
Nltralln, Tri-
fluralln
Chlordane, ...
Chloroform,
2,4-D, DCT
DDT, PCP - -
Amlben5, 2,4-D, -
DDT, PCP
Chlordane , DDT, - -
Endrin, Hepta-
chlor, Llndane
A Idr in, Amiben-, -
2,4-D, Dleldrin,
Methoxychlor ,
PCNB, PCP, 2, 4, 5-T
Organochlorlne
still bottom
residues
Aldrln. DDT,
Dleldrin, PCB's,
Toxaphene
a/ AS classified in Lawless ct al. (1975).
192
-------
Incineration of most other pesticide classes has not been adequately
studied although there have been studies of representative pesticides of
several classes, such as malathion, disulfoton, zineb, atrazine, captan, and
picloram. We call attention to the absence of incineration data within the
nitrogen-containing classification for anilides, ureas, uracils, nitrated
hydrocarbons, and other types of pesticides. It is important to note that EPA
recommends recovery of economic values for heavy metal pesticides and recom-
mends against high temperature incineration of organometallics which contain
organic mercury, lead, cadmium, or arsenic (Federal Register, 1974).
Biological methods, including bacterial and enzymatic processes, are
under rapid development, but many classes of pesticides have yet to be in-
vestigated with these methods. Biological disposal techniques are under-
researched and underdeveloped at present.
Many photolytic studies of individual pesticides in several classes have
been performed, but practical or large-scale demonstration of this method has
not been reported except for the degradation of TCDD. Much basic laboratory
and field data on the fundamentals of photolysis remain to be developed.
Other physical and chemical disposal procedures have been developed and
applied to pesticides on what has been almost a random basis. The techniques
of microwave plasma and molten salt baths have been utilized to develop useful
data for several pesticide classes. However, both of these methods presently
remain at the bench level and have yet to be demonstrated on a large scale.
Catalytic liquid disposal processes are presently only laboratory demon-
strations although reductive degradation by metallic couples is under pilot-
scale development and testing. Again, only a few classes of pesticides have
been examined.
Land disposal of pesticides has been the focus of several R&D studies,
and a fairly large body of information over several classes of pesticides has
been developed on this method. Sanborn (1977) has suggested that land disposal
may be limited to specific pesticides and may not be a generally applicable
procedure.
The conversion methods, chlorolysis and hydrodechlorination, to recover
economic values have been applied only to chlorinated pesticides; this class
of pesticides may be most amenable to these methods.
Evaluation of Pesticide Disposal and Conversion Methods
As an aid in assessing the potential usefulness of these methods, these
techniques have been rank-ordered in Table 26 according to the potential for
large-scale application; i.e., practical field disposal or conversion tech-
niques for large quantities of unwanted pesticides. The table also presents
193
-------
vO
TABLE 26. TECHNICAL, ENVIRONMENTAL, AND ECONOMI ^COMPARISON OF DISPOSAL OR
CONVERSION PROCEDURES FOR PESTICIDES \
Potential for
Disposal or large scale Current status- Potential Environmental
conversion method application of technology*' application^/ ImpactS/
Incineration
Activated carbon and resin
adsorption
Chlorolysls
Microwave plasma destruction
Molten salt baths
Hydrolysis
Reductive degradation with
metallic couples
Wet air oxidation
Hydrodechlorination
Ozonation/UV Irradiation
Catalytic dechlorination
with nickel borlde
Sonocatalysis and cata-
lytic ozonatlon
Biological
Photolysis
Land disposal
Chemical fixation
High
High
High
High
Medium
Medium
Medium
Medium
Low
Low
Low
Low
Low
Low
Low
Nil
1
1
1
2
2
2
2
2
2
2
2
3
3
3
3
3
4
5
5
4
4
5
5
5
5
5
5
5
5
5
5
6
7,
7,
7,
7,
7,
8,
8,
8,
8,
8,
8,
8,
8
8,
9
9
10
10, 11
10, 12
10
10
10
10
10
10
10
10
10
10
Economic
cost impact"-'
16
14, 17
16, 17, 18
14
16
13
14
15
14, 17
16
14
16
14
14
13
13
a/ 1. Method is at or near demonstration phase. 2. Proven research method. 3. Limited or no data
base.
b/ 4. Potential wide application for many classes of pesticides. 5.
application.
Limited application. 6. Unproven
c/ 7. Potential controllable method with a minimum environmental impact. 8. Potential residual
toxiclty of decomposition products. 9. Unknown fate of disposed pesticides. 10. Potential
ash or wastewater disposal problem. 11. Requires recycling or disposal of adsorption medium
and adsorbed pesticides. 12. Chlorine gas handling problems. Potential release of chlorocar-
bons to the environment.
d/ 13. Low capital investment and moderate operating costs. 14. Moderate capital Investment and
operating costs. 15. Large capital investment and moderate operating costs. 16. Large capital
investment and operating costs. 17. Resource recovery option. 18. Potential return on Invest-
ment.
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qualitative statements concerning potential environmental and economic impacts.
Each disposal or conversion method has advantages and disadvantages and these
are briefly indicated in Table 26; details may be found in earlier Sections
of. the teporto
Those methods categorized as "High" and "Medium" appear to hold promise
for large-scale application and are worthy of continued research and develop-
ment. Those methods categorized as "Low" may not be viable as practical
large-scale disposal or conversion methods. Or, a more complete data base may
be required for proper assessment. Chemical fixation is probably a misapplica-
tion for the disposal of pesticides.
Tables 25 and 26 present the state-of-the-art information base for pes-
ticide disposal by pesticide category for incineration, biological, physical-
chemical treatment, land disposal, and conversion methods. The tables are
useful as a capsule review of what research and development for the disposal
or conversion of pesticides has been accomplished and where specific technical
information gaps exist»
» .
;Technical Information Gaps
Obviously, much of the vital information required to develop and advance
many of the alternate disposal or conversion procedures for pesticides re-
mains to be generated at the laboratory level. Other procedures need to be
advanced to the pilot plant level. Still others require more detailed environ-
mental and/or economic impact assessment. Not one method described in the
body of the report is ready for full-scale general application. This general
statement is valid for individual methods when the various factors (techni-
cal information base, environmental impact, and economic impact) are all taken
into considerations
RECENTLY IDENTIFIED PROBLEM PESTICIDES
In spite of the large amounts and variety of pesticides produced and used
annually in the United States, approximately 55 pesticide Al's and their
associated formulated products are considered waste disposal "problems" be-
cause of general human health or ecological concern or specific, widely re-
ported incidentso Table 27 lists the "offenders" and is a compilation based
on references given at the bottom of the table. This list includes so-called
"RPAR" chemicals, i0e., those pesticides whose re-registration is being
questioned by the EPA, but does not include all pesticides that pose a poten-
tial disposal problem. Rather, it identifies current and past prominent cases
involving some problematic pesticides which have been or are produced in rela-
tively large quantities.
195
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TABLE 27. RECENTLY IDENTFIED PROBLEM PESTICIDES
Pesticide classification
Problem pesticides
Inorganic and metallic-organic
pesticides
Phosphorus-containing pesticides
Nitrogen-containing pesticides
Halogen-containing pesticides
Sulfur-containing pesticides
Botanicals and microbiological
pesticides
Organic pesticides, not elsewhere
classified
Organoarsenicals and organomercury
compounds, PMA,* thallium sulfate
DDVP,* DEF® dimethoate, EPN,* merphos
phosvel®, ronnel, trichlorfon
Amitraz, benomyl, captan,* carbaryl,*
diallate, kaybam, maleic hydrazide,
maneb, monuron,* nabam, paraquat,
pronamide, triallate, zineb*
Aldrin,* BHC, chloranil, chlordane,*
chlorobenzilate, chloroform,* DBCP,
DDT,* dieldrin,* endrin,* ethylene
dibromide, heptachlor,* Herbicide
Orange,* Kepone®,* lindane,* mirex,*
methoxychlor,* PCNB,* PGP,*
Perthane®, Strobane®, 2,4,5-T,*
toxaphene,* trichlorfon
Aramite®
Strychnine
Compound 1080, creosote9 ethylene
oxide, piperonyl butoxide
Source: U.S. Environmental Protection Agency, Washington, DoC., February
1976.
Chemical and Engineering News, June 14, 1976, p. 18o
Pesticide and Toxic Chemical News, 5(32), July 6, 1977. Special
Index Issue.
* Problematic pesticides that have been evaluated in pesticide disposal
research studies.
196
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Many in-depth studies to learn the most efficient and complete route for
destruction of several of these formulated pesticides have been performed.
Thus, as cited earlier, many studies have been concerned with DDT; and at
least two incineration studies each of Herbicide Orange and Kepone® have been
performed.
The pesticide of most recent concern in the fumigant, l,2-dibromo-3-
chloropropane (DBCP), manufactured in the past by Dow Chemical—USA, Occidental
Chemical Company, and Shell Chemical Company* Recent production levels may
have been near 9,000 MT (20 million pounds) annually. There has not been a
single in-depth study performed to learn how to destroy this chemical econom-
ically and efficiently.
A review and evaluation of the published literature revealed that of the
55 chemicals previously listed as potential or actual pesticide disposal prob-
lems, 23 have been researched for potential disposal methods which could be
made environmentally acceptable. In Table 27 these pesticides have been indi-
;Cated by an asterisk. Incineration appears to be the only practical disposal
• route for many of these pesticides since they are largely refractory, highly
chlorinated chemicals.
t
SELECTED DISPOSAL PROCEDURES
In this subsection selected disposal procedures are discussed for both
small and large quantities of unwanted pesticides. The first category is
relevant to the disposal of < 25 kg (< 50 Ib) or < 20 liters (< 5 gal.) of
pesticide as may be required by the layperson (farmer, householder, county
extension agent, etc.), and the second category relates to the disposal of
"tonnage" quantities of pesticide that may be required by the EPA, state and
local agencies, manufacturers, and formulators.
These areas have been addressed by two previous documents by Lawless
et aL (1975) and Shih and Dal Porto (1975). Each contains much useful in-
formation on the disposal of pesticides.
Disposal of Small Quantities of Pesticides
The recommendations addressed to the layperson in Lawless et al. (1975)
are still--largely valid although recent Federal, state, and local regula-
tions may make some specific recommendations obsolete. Thus,, for each pesti-
cide or mixture, one or more disposal procedures may be selected from the
recommended listing. These procedures have previously been categorized and
presented in Table 12.
, Any chemical detoxification procedure carried out by the layperson must
be done with the utmost caution. Further, some degradation processes which
197
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destroy the AI may leave unknown or unsuspected toxic residues; e.g., the
acid hydrolysis of Diazinon®• This finding causes any chemical detoxifica-
tion process to be "suspect" until the residual products are determined to
be safe; e.g., by aquatic bioassay.
Burial in the ground or ground surface disposal of small quantities of
pesticide would be perraissable, provided that these procedures are not locally
restricted and with cognizance of potential groundwater contamination and pre-
ventive action taken*
Prohibited methods, or those likely to be prohibited in the near future
include: open dumping, open burning (except small amounts of empty com-
bustible containers), water dumping, ocean dumping, and well injection with-
out a permit* Release to the atmosphere of volatile compressed gases or
aerosol formulations is suspect because of potential, unknown photolytic re-
actions occurring in the atmosphere, and/or the release of chlorofluorocar-
bons which may be part of the propellant system.
The report on pesticide Jisposal previously cited (Lawless et al. (1975)
clearly emphasizes safety precautions appropriate for the layperson and urges
the use of good personal judgment and caution in applying any disposal pro-
cedure recommended by responsible authorities. The layperson should make no
attempt to conduct chemical detoxification procedures if any of the extremely
toxic pesticides are involved (1050 £ 10 mg/kg) or if substantial amounts
(s» 25 kg or a 20 liters) of surplus pesticides are to be disposed.
Further, chemical detoxification methods are inherently potentially
dangerous. A recent report on chemical methods of pesticide disposal (Shih
and Dal Porto, 1975) emphasizes that treatment by alkali is effective and
environmentally sound method for only 7 of the 20 prominent pesticides in-
vestigated. The report cautions against acid or alkaline hydrolytic treatment
that might yield degradation products that are either toxic or may be sus-
pected carcinogens. A final conclusion of the report is that there is presently
insufficient information to develop chemical detoxification procedures for
most of the pesticides commonly in use.
Presented in Table 28 are the 14 general disposal procedures for possible
application by the layperson to the seven classes of pesticides considered in
this report. The table indicates the number of times a particular disposal
procedure is the preferred procedure for each class of pesticide. Procedures
1,2, and 3 are similar and have been considered as equivalent; however,
some pesticides can be disposed of by several recommended procedures.
Procedures 1 through 3 are recommended moat frequently for pesticide
disposal. Incineration is an effective disposal procedure but generally un-
available to the layperson. Open burning, dilution, and release to the air
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TABLE 28o RECOMMENDED DISPOSAL PROCEDURES FOR SMALL QUANTITIES OF UNUSED PESTICIDES
VO
VO
No.
1.
2.
3.
It.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
Pesticide classification^/
Inorganic and Phosphorus- Nitrogen- Halogen- Sulfur- Bontanical and
metallo-organic containing containing containing containing microbiological
pesticides pesticides pesticides pesticides pesticides pesticides
Number in Class 82 93 189 90 15 19
Disposal procedures
Turn in to pesticide 42 80 27 12 5 4
collection center
Return to supplier 42 80 27 12 5 4
Turn in to industrial 42 80 27 12 5 4
waste service
Place in trash for pick- 1 12 I 2
up service
Incineration 5 - 91 64 10 2
Open burning - -2-5 2
Treatment with alkali 4 34 18 6 3
Treatment with acid - 1 12 1 -
Treatment with oxidants 3 1-12
Treatment with reducing - - - .- - .
agent
Burial in the ground 38 3 33 6 12 2
Ground surface dilution 1 - 5 2 1
Dilution 2 - 1 - 3 2
Release to the air - - - 1 1
Organic .
pesticides,
not elsewhere
classified
45
2
2
2
5
10
1
1
-
-
-
16
2
4
2
Total.
533
172
172
172
21
182
10
66
14
7
0
110
11
12
4
a/ As classified in Lawless ct al. (1975).
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would not be permissible under some conditions or are contrary to recommended
procedure. Burial or ground surface disposal must not be performed unless ap-
propriate precautions are taken to assure that ground and surface water con-
tamination does not occur. The remaining procedures involve chemical detoxifi-
cation which should be undertaken with the utmost caution and with consultation
from the pesticide "handbook" (Shih and Dal Porto, 1975) and/or "disposal
guidelines" (Lawless et al., 1975) and upon recommendation from a responsible
authority.
Disposal of Large Quantities of Pesticides
The disposal of large quantities of unwanted pesticide is hindered by
definite information gaps about the available methods as noted by a recent
Office of Solid Waste Management Programs document (Munnecke et al. 1976).
Specifically, for biological and land disposal techniques, the roles and
utility of soil incorporation, activated sludge, and bacterial/enzymatic
methods are poorly understood and have not been sufficiently researched at
present. The fundamental research and development questions posed by Munnecke
et al. (1976) have not been answered. These questions are concerned with:
pesticide volatilization and the potential hazards to workers in the area;
degradation rates; pesticide migration in soil; and economic considerations.
The reader is referred to Munnecke et al. (1976) for further details of
present technology gaps.
For incineration technology, the basic questions regarding operating
parameters and limitations for commercial incinerators currently available
have not been completely answered. These questions include: which pesticides
and which formulations can safely be incinerated; what constitutes proper
handling of pesticides and their containers prior to the actual incineration
process; what are the necessary operating conditions for complete degrada-
tion; what constitutes proper control of off-gases; and what constitutes safe
disposal of ash residues?
Many of the pesticide incineration studies have been made with special-
ized, research type incinerators rather than commercially available incinera-
tors, thus creating a potential difficulty in extrapolation of research data
to practical field disposal conditions.
As of the time of this writing (May 1978) no incinerators or classes of
incinerators have been designated as the standard of comparison for effi-
ciency of destruction nor have limits been defined for acceptable effi-
ciencies. Tentative operational conditions of two second dwell time at.
1000°C have been established, but the applicability of these or other sets of
operational conditions to the various classes of pesticide has not been clearly
established.
200
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Thus, the EPA is not yet in a position to«provide concise recommendations
to manufacturers, distributors, state and local;agencies as to the best tech-
nology for incineration of large quantities of pesticides*
Many studies of physical-chemical disposal methods have been carried out
at the bench •'scales but no chemical procedure has been recommended for dis-
posal of largV quantities'3f-s'any specifefe^class of pesticide* ('Several tech-
nologies, hdweverj^may ultimately be successful.) Research has shown that
present physical-chemical procedures generally fall short of 100% destruc-
tion o Often times,"only a portion of tEl^pesticide molecule is affected and
the intermediate material may be as hazardous as the original AI.
Information gaps include uncertainties about: the ultimate role that
hydrolysis reactions may playi the effect of concentrated chemical environ-
ments on general decomposition parameters derived from dilute solution data;
and the environmental effects of the final reaction mixture after the
degradation/detoxification reaction is complete.
The possible use of sequential combinations of chemical and biological
treatment of pesticides has not been investigated extensively for pesticide/
disposal*
In summary, there has not been a single biological', incineration, or
physical-chemical degradation method advanced for wide usage by the layperson
in .the field or for use in decomposing large quantities of pesticides by
trained personnel.
The crucial problem of disposal of large quantities of unwanted pesti-
cides remains unsolved., Critical information necessary for the large scale
use of biological, landfills incineration, and physical-chemical procedures
is unavailable at the present time. Research in all these areas remains at
the bench level and must be advanced to the pilot plant demonstration level
with the further stipulation that whatever disposal procedures are selected
they must be commercially adaptable*
NEW DIRECTIONS FOR DISPOSAL RESEARCH AND DEVELOPMENT
On the basis of the information developed in this report, new directions
can be suggested for research and development appropriate to field disposal
of: (a) small quantities of pesticides and (b) large quantities of pesticides.
Small Quantities of Pesticides
Disposal research and development is divided into two areas: (a) chemi-
cal detoxification procedures that are proven to be effective, safe to the
^layperson, and environmentally sound; and (b) procedures appropriate to mix-
tures of pesticide Al's as may be found in finished formulations*
201
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Chemical Detoxification Methods-
Based on information contained in the report by Lawless et al., we cite
a passage having a bearing on the appropriate direction that research and
development for the disposal of small quantities of pesticides should take:
"Over 25% of the pesticides are so hazardous to man or the en-
vironment or the 'State of knowledge on their degradation is so incom-
plete that the recommended disposal procedure is for the layperson to
place his pesticide in the hands of a professional rather than to at-
tempt to detoxify himself; i.e., turn it into a collection center,
return it to a supplier, or transfer it to an industrial waste service.
For all but the most toxic of these pesticides, however, alternative
disposal procedures have been listed. Another group of approximately
30% of the pesticides are so environmentally persistent, thermally
stable, or resistant to chemical degradation that the preferred dis-
posal procedure is incineration in efficient equipment of a type not
normally owned by a layperson. Alternate disposal procedures have
also been suggested for many pesticides of this group. For the re-
maining 45% of the pesticides, disposal procedures are recoranended
which the layperson can use: chemical detoxification is suitable for
157o of the total and either burning, ground burial, ground surface
disposal, dilution, or release to the air may be employed for 30% of
the total." (Lawless et al., 1975, p. v).
Thus, of some 550 commercially important pesticide Al's, only approxi-
mately 80 may be detoxified safely by chemical treatment by laypersons. Further
examination of the primary recommended methods indicates that 60 involve al-
kaline hydrolysis; 13 involve acidic hydrolysis, and 6 involve treatment with
oxidants (e.g., bleach or hydrogen peroxide). No primary recommended methods
to dispose of synthetic organic pesticides involve reductants (e.g., sodium
thiosulfate or sodium bisulfite).
Examination of secondary recommended chemical treatment methods show
that alkaline hydrolysis is an alternative for 107 pesticides, acidic hy-
drolysis for 6 pesticides, and chemical oxidation for 4 pesticides. Again,
alkaline hydrolysis is the major choice (167 cases) for chemical detoxifica-
tion.
As developed in Section 6, alkaline hydrolysis of pesticides has been the
subject of several research studies. These studies indicate the potential
usefulness of this general method for specific classes of pesticides (e.g.,
organophosphorus compounds and carbamates), but as yet there has not been
widespread acceptance of the method.
Appropriate research and development is to focus on the prominent method,
alkaline hydrolysis, and require that the final reaction product mixture of
any disposal method be nontoxic to fish, wildlife, and the environment as a
202
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whole as well as being safe for the layperson to perform* This may neces-
sitate chemical analysis and/or aquatic bioassay after neutralization of the
excess hydroxide*
Similar studies could be undertaken for acidic hydrolysis or chemical
oxidation, but the total number of pesticides for these categories is only
approximately 20 to 30, depending on whether the methods include primary or
both primary and secondary recommendations*
The question of the advisability and utility of chemical treatment of
pesticides by the layperson can be answered by a minimum of additional re-
search and development studies of alkaline hydrolysis with analysis and
aquatic bioassay of the final reaction mixture* Any chemical treatment which
cannot be made environmentally safe or which does not possess a minimum risk
should not be considered potentially useful even though it successfully
detoxifies the AI.
It is not necessary to apply alkaline hydrolysis with aquatic bioassay
tests to all 167 pesticides. It is more appropriate to consider only those
jiitilized in relatively large quantities, ^ 1,000 MT (^ 2 million pounds)
annually. Table 29 indicates 26 candidate pesticides as arranged by class and
decreasing estimated production level*
Pesticide Mixtures-
Many common agricultural, home, and garden products contain mixtures of
several pesticide Al's combined with adjuvants, diluents, solvents, and
synergists* An example is an insecticide containing toxaphene 0*7 kg/liter
(6 Ib/gal.) and methyl parathion 0.2 kg/liter (2 Ib/gal.) which is marketed
as an emulsifiable concentrate. A second example is a rose and floral dust
fungicide-insecticide combination containing carbaryl 3% (W/W), dicofol 1*5%
(W/W), folpet 5% (W/W), and malathion 4% (W/W).
The exact number of pesticide products containing two or more Al's is
unknown but may be in excess of 500 (Billings, 1975). Likewise, estimates of
individual and total production of these pesticide mixtures is unknown* The
popularity of these products is highly variable*
Practically all previous laboratory studies have determined disposal pro-
cedures for pure Al's but seldom have commercial pesticide products been ex-
amined. What is needed are disposal methods suitable for the layperson for
finished formulations which may contain two or more Al's. It is insufficient
to direct a small farmer to treat small quantities of the toxaphene and methyl
parathion formulation cited earlier with caustic to destroy the methyl para-
thion because toxaphene will be largely unaffected. In this case, caustic
treatment followed by burial is advisable or simply burial alone.
203
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TABLE 29. ESTIMATED PESTICIDE PRODUCTION IN QUANTITIES LARGER THAN 1,000
METRIC TONS PER YEAR
Category
Estimated 1974 production
(metric tons)
Phosphorus-containing pesticides
Methyl parathion
Malathion
parathion
Diazinon®
Disulfoton
Phorate
Fensulfothion
DEF®
Guthion®
Dimethoate
Ethion
Naled
Ronnell
Nitrogen-containing pesticides
Atrazine
Carbaryl
Captan
Simazine
BUX®
Carbofuran
. Me thorny 1
Propazine
Folpet
Halogen-containing pesticides
2,4-D
Dalapon
Silvex
Dicofol
Total 26 pesticides
23,000
14,000
7,800
5,500
4,500
4,500
2,700
2,300
2,300
1,400
1,400
1,400
1,400
50,000
26,000
9,100
6,800
4,500
4,500
4,500
4,500
1,400
25,000
2,300
2,300
1,800
214,900
Source: Kelso et al. (1976).
204
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One rule of thumb may be applicable: from the label on the package deter-
mine the nature of the pesticide Al mixture and apply that procedure which is
appropriate to the most toxic and/or most refractory materials contained in
the package. In many cases, incineration may be the preferred method. Often
the best procedure for the layperson would be to turn the pesticide into a
collection agency, a county extension agent, or return to the manufacturer
or distributor. Disposal must be considered on almost a case-by-case basis
as noted by Lawless et al. (1975) because of the large number and variability
of pesticide mixtures0
1 . ' D.
An appropriate research approach may be to contact the largest pesticide
manufacturers and femulators to determine which specific finished formula-
tions containing two or more Al's are their most widely sold products, obtain
from them suggestions as to how best to dispose of small quantities of these
pesticides and their containers, and then investigate these procedures--
following the suggested general procedures outlined by Lawless et al. (1975)
and Shih and Dal Porto (1975)—-in order to reduce them to standard methods.
Alternately, the EPA may require the manufacturers and femulators to
•research and develop disposal procedures as part of the re-registration
process.
Disposal of Large Quantities of Pesticides
Research and development focuses on three areas: incineration at sea,
mobile disposal units, and fixed disposal units, including commercial in-
cinerators.
Incineration at Sea—>
The potential environmental and economic cost-benefits derivable from in-
cineration at sea have been discussed in Section 4. Appropriate research and
development activities for the EPA may be to continue the incineration at sea
studies by leasing the facilities of the Vulcanus and/or Matthias III in-
cinerator ship. This approach has an additional advantage because it is, in
many cases, easier, safer, and more economical to transport an ocean-going
incinerator facility to a point near the hazardous waste than to transport
the waste to a regional, fixed incinerator unit. Movement of hazardous wastes
across state boundaries has been a politically sensitive issue in recent years
and will likely continue to be so.
The use of two incinerator ships is proposed to serve the coastal por-
tions of the United States where most of the petrochemical complexes are
situated. The need for two ships rather than one is based partly on the as-
sumption that incinerator overhaul and maintenance and dry dock time may be
a significant factor in overall operations and that there are inherent advan-
tages in permanently stationing one ship on the West Coast and having one ship
serve the East and Gulf Coasts. The service of the incinerator ships could be
205
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made available to Canada and Mexico, thus increasing their potential utility*
The latter point is an important one since Mexico will probably be developing
oil fields and building refinery complexes on the Gulf of Mexico in the near
future*
Mobile Disposal Units—-
For the portions of the continental United States not bordering on the
oceans, mobile disposal units may be feasible* Thus, we envision two to five
mobile disposal units mounted on truck beds or rail-truck bed combinations
circulating through the United States to dispose of hazardous wastes on a
demand basis. This concept minimizes movement of hazardous wastes by bringing
the disposal facility as near as possible to the waste and obviates trans-
shipment across state boundaries.
The actual type of disposal device selected is open to further research,
development, and testing. Options include: rotary kilns, fluidized beds,
modified jet engine units (SUE®burner), molten salt baths, etCo, and could
include banks of microwave plasma destructors. Figures 11, 12, and 23 (pre-
viously given) illustrate various options.
Fixed Disposal Units—
The next alternative is to design, construct, and test fixed incinera»
tors located in heavily industrialized or agricultural areas. The placement
of these units should be to the advantage of the central agricultural por-
tions of the United States and with consideration of the vast petrochemical
complexes along the Gulf Coast. We envision a total of four fixed incinera-
tion units placed in the far West, the Plains States, the Gulf Coast, and the
Eastern Seaboard.
An alternative research and development approach to fixed disposal units
is to rely on existing commercial incinerator facilities to handle immediate
and near-term pesticide disposal problems. Examples of two facilities are
Chem-Trol Pollution Services, Model City, New York| and, Rollins Environmental
Services, Inc., Bridgeport, New Jersey. Preliminary incinerator tests, in-
cluding analytical protocol development for sampling and measurement, could
be necessary to insure minimum environmental risk.
Movement of pesticides and other hazardous chemical wastes across state
boundaries may be a problem as indicated earlier. The political overtones of
frequent or even occassional trans-shipment of hazardous materials within the
continental United States is a separate problem that must eventually be ad-
dressed by the EPA, but it is beyond the scope of the present report. Never-
theless, the concept of utilizing commercially available incinerators with
appropriate testing and monitoring could be a cost-effective procedure with
minimum environmental risk and a viable alternative to other more costly in-
cineration research and development optionso
206
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Choice of Incinerator Types—
The choice of incinerator type or types for ocean, mobile, and fixed
facilities is rather limited. Two incineration ships have already been con-
structed and successfully tested and operated. The performance data for dis-
posal of chlorinated hydrocarbons for these two alternate systems are quite
comparable. Thus, the selection of the final design need not be a long drawn
out process and may hinge on projected operating and maintenance costs rather
than technical and performance questions.
The concept of mobile and fixed disposal facilities need not introduce
additional complications. In principle any of the following types of in-
cinerators or disposal units may be made either mobile or fixed: rotary kiln,
fluidized bed, modified jet engine, multiple chamber, and microwave plasma
destructors.
We note the EPA/IERL, Edison, New Jersey, is designing a mobile rotary
kiln (c.f. Figure 12). A fluidized bed incinerator may be an equally viable
AChoice. A multiple hearth furnace (with or without rabble arms) may not be a
sgood choice since refractory linings may crack and/or shake loose. Similarly,
'a mobile molten salt bath may suffer from the same problem. A modified jet
engine burner may be a good choice for a mobile unit since it is relatively
small, light weight, and does not require massive bulkheads or refractory
linings. Banks of microwave plasma destructors may be feasible, but they
probably would not be able to handle large amounts (multiple tonnage quanti-
ties) of chemical wastes.
Synopsis of New Directions for Pesticide Disposal Research--
We recognize that heavy emphasis has just been given to incineration
procedures with the near exclusion of physical-chemical, biological, and land
disposal methods for the disposal of large quantities of unwanted pesticides
and other hazardous chemicals. The rationale for this position is simple:
no technology other than incineration is ready for demonstration, as previously
indicated in Table 26.
When, and if, alternate physical-chemical and biological disposal proce-
dures have been demonstrated at the pilot plant level to offer technical,
environmental, and/or economic cost advantages over incineration, then we
presume one or more such facilities will be constructed or leased and utilized.
The EPA can reasonably expect benefits from several alternate methods as the
result of continued research and development, but only in the mid-to-long-
range time interval; i.e., > 5 years. Over the next 5 years the need to at-
tend to the immediate disposal of large quantities of unwanted pesticides
and/or chemical wastes must rely on incineration.
207
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REFERENCES
Billings, S« C. ed. Pesticide Handbook-Entoma 1975-1976. The Entomological
Society of America, College Park, Maryland, 1975.
Federal Register. 39(85):15236-15241, May 1, 1974.
Kelso, G. L., R. R. Wilkinson, I. L. Ferguson, and J. D. Maloney, Jr. De-
velopment of Information on Pesticides Manufacturing For Source Assessment.
Contract No. 68-02-1324, Task 43, U.S. Environmental Protection Agency
Industrial Environmental Research Laboratory, Research Triangle Park, North
Carolina, July 1976.
Lawless, E. W., T. L. Ferguson, and A. F. Meiners. Guidelines for the Dis-
posal of Small Quantities of Unused Pesticides. U.S. EPA-670/2-74-057,
June 1975.
Meier, E. P., M. C. Warner, W. H. Dennis, Jr., W. F. Randall, and T. A.
Miller. Chemical Degradation of Military Standard Formulations of Organo-
phosphate and Carbamate Pesticides. Technical Report No. 7611. U.S. Army
Medical Bioengineering Research and Development Laboratory, Fort Detrick,
Frederick, Maryland, AD A036051, Nov. 1976.
Miinnecke, D., H. R. Day, and H. W. Trask. Review of Pesticide Disposal
Research. Environmental Protection Agency Office of Solid Waste Manage-
ment Programs Report SW-527, 1976.
Sanborn, J. R., B. M. Francis, and R. L. Metcalf. The Degradation of Se-
•lected Pesticides in Soil: A Review of the Published Literature. EPA-600/9-
77-022. Aug. 1977.
Shih, C. C. and D. F. Dal Porto. Handbook for Pesticide Disposal by Common
Chemical Methods. PB-252 864. Dec. 1975.
208
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APPENDIX A
RECENT CONTRACTS FOR HAZARDOUS WASTE MATERIALS
DISPOSAL RESEARCH
Appendix A contains a compilation of recent contracts approved by the
EPA and other agencies and organizations to investigate new options for dis-
posing of hazardous toxic wastes, including pesticides. The compilation
presents the following informationo
* Sponsor
* Contract number
* Project officer
* Contractor
* Contract value
* Time interval
* Principal investigator
* Title
* Objectives
* Other related information
EPA/IERL, Contract No« 68-03-2491, Dr» John Brugger^/
ATLANTIC RESEARCH CORPORATION (ARC) $65K, 2 years
Principal Investigator, Dro Ralph Valentineo Start: June 1977.
Biodegradation of Hazardous Wastes by Pure Bacterial Cultures
Activated sludge processes are probably the cheapest method of disposal,
but some wastes are not normally degradedo These wastes pass through the
a/ EPA/IERL, Oil and Hazardous Materials Spills Branch, Edison, New Jersey
~~ 08817.
209
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treatment facility essentially unchanged and contribute to the total chemical
oxygen demand (COD). Aerobic organisms have inherently faster metabolic rates
than anerobic organisms. Gram negative bacteria, fungi, and yeast have been
successful in disposing of pesticide and agricultural wastes. The ARC approach
will be to find/ develop the proper organism(s) to degrade hazardous waste
materials (HWM) by exploiting pure or mixed pure cultures of bacteria. "Sol-
ubilization" of the HWM is important in order to have intimate contact be-
tween the organisms and the HWM.
ARC has been successful in degrading pentachlorophenol (PGP) at 700 ppm
to around 350 to 420 ppm. In practice, PGP and its metabolites are monitored.
ARC is now working on hexachlorocyclopentadiene wastes. The proper matrix
may be aqueous or mudlike material.
.In any use of pure cultures or mixed pure cultures, there is concern
over the survivability of the pure culture in the field. The problem of over-
growth by indigenous organisms is ever-present. Biodegradation by pure cul-
tures may be an optional stage after activated sludge treatment.
v
EPA/IERL, Contract No. 68-03-2493, Dr. John Brugger
ATOMICS INTERNATIONAL, $150K, 2 YEARS
Principal Investigator, Dr. A. J. Darnell. Start: June 1977.
Oxidation/Bromination of Hazardous Waste Material by an Electrolytic Process
HWM, bromine, and water are combined at 300°C in a closed system to form
carbon dioxide and hydrobromic acid. The overall reaction is
C,H + 5/2 Br2 + 2H0 - ^-> C0 + 5HBr
(Hazardous Waste Material)
Sulfur and phosphorus-bearing compounds yield sulfates and phosphates which
are collected as residues. Bromine iso recovered from hydrobromic acid by
electrolysis at 250°C.
Apparatus includes a stainless steel-tantalum reaction chamber. The
chamber has individual entry ports for introduction of HWM, water, and re-
circulating dilute hydrobromic acid-bromine solution and exit ports for
escape of gases and inorganic residue removal.
Applications include petroleum products and some pesticides. Wood scrap
may be completely consumed in 30 to 60 min at 250°C» Experimental work was
reported to indicate that chlorine-containing compounds yield HCl as a
product, but compounds similar to Kepone® have not been studied. The appli-
cability of the material to chlorinated organic s must be viewed with reserve
until adequately demonstrated.
210
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Bromine consumption is significant and appears in the "ash" or inorganic
residue* These bromine values may be recovered by treatment with dilute sul-
furic acid*
EPA/IERL, Contract No0 68-03~2494, Dr» John Brugger
BATTELLE-PACIFIC NORTHWEST LABORATORIES, $45K, 9 MONTHS
Principal Investigator, Mr» Basil Mercero Start: June 1977.
Methods and Materials Annotated Matrix
A paper study of techniques dealing with HWM spills.. The study attempts
to answer the following types of questions:
10 What are the major areas of concern in the environment?
2o What are the assessments of conventional methods of destruction of
HWM spills?
3« How can specific examples of HWM spills be best handled, e.g., Kepone®
in James River sediments and PCB's in Hudson River sediments.
The objective is to develop a matrix of methods of handling HWM spills.
EPA/IERL, Contract No<> 68-03-2492, Dr. John Brugger
MINE SAFETY APPLIANCE RESEARCH, $7 OK, 2 YEARS
Principal Investigator, Mr<> Ralph Hiltzo Start: June 1977 «
Glass Enc ap su 1 at i on
When potassium superoxide and calcium carbide are mixed and heated in
the presence of oxygen, an exothermic reaction occurs:
2K02 + CaC2 + °2 — T"* K2° + Ga° + 2c°2 + heat
If hazardous waste materials, MgC03, Al203> Si02, and 6203 are also added to
the above reactants, the heat of the reaction forms glass in situ, and the
wastes are incorporated into the glass as it is formed.
Mixing problems as well as crazing or cracking of the final product may
be significant,, This method would also have a high energy requirement overall.
211
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EPA/IERL, Contract No. 68=03-2492, Dr. John Brugger
MINE SAFETY APPLIANCE RESEARCH, $80K, 2 YEARS
Principal Investigator, Mr. Ralph Hiltzc Start: June 1977.
Molten Alkali Metal Reduction
When waste materials are placed in sodium metal (200 to 400°C) in an
argon atmosphere, total reduction occurs. Various substances may be formed,
e.g., nitrogen, hydrogen, arsine, phosphine, etc. Metals are "amalgamated."
The molten sodium system may be limited in application. Cleanup of the
sodium after disposal of hazardous waste materials is required to remove
sodium oxide, sodium hydroxide, and silicates. Chlorides, sulfates, and phos-
phates stay in solution. The waste must be dried first, otherwise the water
will react with the molten sodium.
Considerable engineering skill will be required to buildj operate, and
maintain the system* Liquid sodium at 200°C circulates (by means of an elec-
tromagnetic pump) and flows into an expansion chamber which also serves as
the entry point of the HWM below the surface of the liquid sodium. From the
expansion chamber, the liquid sodium and wastes flow to a 316 stainless steel
reactor where the temperature is raised to 400°C and final decomposition
takes place. The decomposed wastes and liquid sodium flow to a "cold" trap
maintained at 200°C where various sodium reaction products precipitate. A
section of the "cold" trap may be removed for cleaning if the system becomes
plugged by the insoluble reaction products.
Overall, this disposal method would have a fairly high energy requirement.
EPA/IERL, Contract No. 68=03-2559, Dr. Richard Dobbs^/
ITT RESEARCH INSTITUTE $7 OK, 1 YEAR
Principal Investigator, Dr<> Eo Foctman. Start: July 1977o
Treatment of Carcinogenic and Other Hazardous Organic Materials by
Biological and Physical/Chemical Processes
Selected carcinogens (e.g., benzidine, naphthylamine, nitrosarnines, etc.)
are to be treated by various disposal options including ozonation/UV irradia-
tion, activated carbon treatment, biodegradation, and other physical-chemical
methods. The study may include two or three as yet unnamed pesticides.
a/ EPA/MERL, Wastewater Research Divisions Physical and Chemical Treatment
Section, Cincinnati, Ohio 45268«
212
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APPENDIX B
PESTICIDE'S AND PESTICIDE CONTAINERS: REGULATIONS FOR ACCEPTANCE
AND RECOMMENDED PROCEDURES FOR DISPOSAL AND STORAGE
215
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TOfo 40—-Projection of Environment
CMAPTEK II—ENVIRONMENTAL
PROTECTION AGENCY
ass—PECULATIONS FOE THE AC-
CEPTANCE OF CERTAIN PESTICIDES
ANE> RECOMMENCED PROCEDURES
FOE? THE DISPOSAL AND STORAGE OF
PESTICIDES AND PESTICIDES CON-
The previous Federal pesticide legis-
lation, the Federal Insecticide, Fungicide.
and Rodentlclde Act of 1947 (7 U.S.C. 135
et seq.), known as FIFRA, did not address
the problems of disposal or storage. How-
ever, the Federal Environmental Pesti-
cide Control Act of 1972 (PL 92-516, 86
Stat. 973) alters and broadens FIFRA to
provide for the first definitive control of
pesticide, and pesticide container, dis-
posal and storage. Under section 19 (a) of
the amended Act, the Administrator of
the Environmental Protection Agency is
required to "establish procedures and
regulations for the disposal or storage of
packages and containers of pesticides and
for disposal or storage of excess amounts
of such pesticides, and accept at con-
venient locations for safe disposal a pes-
ticide the registration of which Is can-
celed under section 6(c) if requested by
the owner of the pesticide." The regula-
tions for acceptance, and recommended
procedures for disposal and storage, con-
tained herein represent the Agency's first
issuance in accordance with the provi-
sions of section 19 (a) of the new Act.
The potential seriousness of health and
environmental hazards due to Improper
disposal and storage of pesticides and
containers became Increasingly clear in
the late 1960's, as documented case
studies accumulated. Expanding usage of
pesticides In the United States (an esti-
mated 665 million pounds in 1968) and
Increasing numbers of spent containers
requiring disposal (240 million in 1968,
up 50 percent over the number in 1963)
indicated that these problems could be
expected to increase. Since little was
Known of the extent of the problem, or
of proper methods of disposal and stor-
age, the Working Group on Pesticides,
composed of experts from several Fed-
eral departments, was asked to study the
subject. Their Initial recommendations
'were published under the title "Summary
of Interim Guidelines for Disposal of
Surplus Waste Pesticides and Pesticide
Containers." More recently, in 1972 a
Task Force on Excess Chemicals, with
representation from all parts of the En-
vironmental Protection Agency, was
formed to study disposal problems relat-
ing to pesticides and other hazardous
chemicals, and to recommend solutions.
In drafting these regulations and rec-
ommended procedures the Agency drew
heavily on the knowledge and informa-
tion developed by these two groups, other
Federal and State agencies "and depart-
ments, and the private sector. Thus, these
documents represent a broadly-based
judgment regarding the pesticide and
container disposal and storage require-
ments necessary to protect the environ-
ment. Compliance Is achievable using
available technology; however, facilities
utilizing *hJs technology are not readily
fi@©UtATt©WS
available to the general public in all geo-
graphic areas at the present time.
Among the new features of the Act is
the requirement that the Administrator
of the Environmental Protection Agency
accept at convenient locations for safe
disposal a pesticide the registration of
which Is canceled under section 6(c) if
requested by the owner of the pesticide.
Section 6(c) of the new Act refers only
to those pesticides the registrations of
which have been canceled after first
having been suspended to prevent Im-
minent. hazards during the time required
for cancellation proceedings. The owner
of such a pesticide is required to make a.
formal request in writing to the appro-
priate Regional Administrator; upon ap-
proval of the request, mutually con-
venient arrangements will be made for
acceptance. Since pesticides finally can-
celed under section 6(c) are not subject
to a grandfather clause, pesticides can-
celed under the FIFRA prior to October
21, 1972, will not qualify. Other canceled
pesticides which do not qualify under the
conditions set forth in section 6(c) of
the new Act will not be accepted pursuant
to section 19(a) of the new Act, and their
safe 'storage or disposal is the respon-
sibility of the owner
The recommended disposal procedures
apply to all pesticides and pesticide-re-
lated wastes, Including those which are
or may in the future be registered for
general use or restricted use, or used
under an experimental use permit. Ad-
ditionally, they also apply to full con-
tainers, spent or used containers, and
container residues. 'Fur packages and
containers of pesticides intended for use
in the home and garden or on farms and
ranches when single containers are to be
disposed of, the Agency does not require
that disposal procedures be followed.
Such disposal will have only minimal en-
vironmental impact and is preferable to
concentrating these products and con-
tainers.
The storage criteria and procedures
apply to all pesticides, pesticide-related
wastes and contaminated containers
which are classed as "highly toxic" or
"moderately toxic," according to EPA's
classification system for pesticides. The
storage of pesticides and their containers
which are In .the mildly toxic category Is
judged not to present any undue hazards
to public health or the environment and,
therefore, is excluded from these criteria
and procedures. The temporary storage
of limited quantities of pesticides in the
other categories, if undertaken at en-
vironmentally safe sites, is also ex-
cluded.
In considering disposal techniques, first
preference should be given to procedures
designed to recover some useful value
from excess pesticides and containers.
Where large quantities are involved, one
of the first recommendations Is that the
excess material should be used for the
purpose originally Intended, provided this
use Is legal. Another alternative is to re-
turn the material to the manufacturer
for potential reuse or reprocessing. A
third alternative, in some cases, may be
the export of the material to countries
where its use is desired and legal.
Should these alternatives be in ap-
plicable, the ultimate disposal method
should be determined, by the type of
material Organic pesticides which do
not contain mercury, lead, cadmium, or
arsenic may be disposed of by Inciner-
ation at temperatures which will ensure
complete destruction. Maximum volume
reduction is achieved by Incineration,
and the Incinerator emissions can be
treated so that only relatively Innocuous
products are emitted. Incineration is
not, however, applicable to those organic
pesticides which contain heavy metals
such as mercury, lead, cadmium, or
arsenic, nor is it applicable to most in-
organic pesticides or metallo-organic
pesticides which have not been treated
for removal of heavy metals.
If incineration is not applicable or
available, disposal in specially desig-
nated landfills is suggested as an alter-
native. However, encapsulation prior to
landfilling is recommended for certain
materials such as those containing"
mercury, lead, cadmium, and arsenic,
and inorganic compounds which are
highly mobile in the soli. Encapsulation,
of these will retard mobility and contain
them within a small area which can be
permanently marked and recorded for
•future reference. Properly rinsed pesti-
cide containers, however, rriay be reused
or recycled as scrap or safely disposed
of in a- sanitary landfill; rinse liquids
which cannot be used should be disposed
of as if they were an excess pesticide.
Among the disposal procedures not
recommended are water dumping, open
dumping, and open burning, except that
open burning of small quantities of cer-
tain containers, and open field burial of
single containers on farms and ranches
by the pesticide user may be acceptable
In some areas.
Other disposal processes, such as soil
injection, well injection, and chemical
degradation, may be acceptable in spe-
cific cases. At present, such methods
have been neither sufficiently described
nor classified to suggest their general
use, and further study Is necessary.
Storage sites and facilities should be
located and constructed to prevent es-
cape of pesticides and contaminated
materials into the environment. Where
practicable, provision for separate stor-
age' of different classifications .of pesti-
cides according to their chemical type,
and for routine container inspection,
should be considered. Special procedures
should be followed In case fires or ex-
plosions occur where pesticides are
stored.
A notice of proposed rulemaking and
issuance of procedures was published in
the FEDERAL REGISTER (40 CFR Part 165)
on May 2?, 1973. The Agency invited the
submittal of comments by July 23, 1973.
Sixty-two letters of comment were re-
ceived and their suggestions were care-
fully considered. The several major is-
sues raised, and the results of the
Agency's consideration of them, follow.
The .largest number of commentsro
Questioned the appropriateness of the
proposed 500 Ib. exclusion from the
recommenced storage procedures, on the
bsato that thers are variation 'ta the
FG9EQAI BEGISTGB, VOL. 39, NO. 05—WBDNeSDAV, MAV 1, W4
216
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RULES AND REGULATIONS
15237
hazards of different pesticides. They
pointed out that a few pounds of one
kind can. In certain cases, represent a
greater hazard than several thousand
pounds of another kind. The Agency con-
cluded that the 500 Ib. exclusion was un-
realistic and that the storage recom-
mendations should be keyed to a rating
system that would consider the overall
hazard of the pesticide and would be
readily apparent to even untrained per-
sonnel. It was decided to adopt the cur-
rent EPA toxlclty rating system for
pesticide labeling. Under that system the
following signal words are required on
labels:
Signal words/symbol
Category required on labels
Highly toxic DANGER, POISON,
Skull and Cross-
bones.
Moderately toxic... WARNING.
Slightly toxic CAUTION.
Pesticides In the first two classes,
highly toxic and moderately toxic, and
which have the corresponding signal
words or symbol on the container label,
will be covered by the recommended stor-
age criteria and procedures. Other pesti-
cides. Including most of those registered
for use in the home antf garden, repre-
sent a lower degree of hazard, and will
not be covered.
Several requests for temporary storage
exemptions from the recommended stor-
age criteria and procedures were made,
for example, by commercial pesticide ap-
plicators operating in remote areas
where availability or construction of rec-
ommended facilities is impractical. These
requests were resolved In two ways.
First, the hazard rating system for rec-
ommended storage procedures will ex-
clude many of the pesticides normally
used. Second, temporary storage for a
single application's amount has been
provided for at isolated and secured sites
where the less stringent criteria and pro-
cedures will not Increase the potential
for environmental pollution.
The statement that these dis-
posal procedures are mandatory only for
the Agency • * •" caused the Environ-
mental Defense Fund to question the ap-
propriateness of the promulgation of dis-
posal and storage recommended proce-
dures instead of regulations, In view of
the FIFRA as amended wording on this
subject. However, adequate disposal sites
and the necessary facilities are not read-
ily available nationwide, and significant
information gaps exist which make it in-
feasible to write specific criteria for cer-
tain disposal methods and procedures.
Further, Information on the full extent
of environmental damages and of the
economic Impact of such regulations Is
lacking. Therefore, the Agency has re-
tained the recommended procedures ap-
proach. At such time as this information
has been obtained and analyzed, con-
sideration will be given to proposing com-
prehensive regulations relative to stor-
age and disposal.
The merit in the comments above de-
rives from the potential for considerable
environmental damage caused by acts
such as water dumping, open ci amp Ing,
open burning, inadequately controlled
well injection, and storage next to food
and feed. Consideration of these com-
ments has led the Agency to begin draft-
Ing a new proposed rulemaking to pro-
hibit or further constrain certain dis-
posal and storage practices, and pos-
sibly to change procedures based on up-
dated information as it becomes avail-
able. It Is expected that this proposed
rulemaking will be published in 1974.
Although section 12 of the new Act
makes unlawful distribution, shipment
or receiving for delivery of an unreg-
istered or canceled pesticide, the Agency
Interprets section 19 as authorizing the
movement of such pesticides for the
specific purposes of disposal or storage.
Several commenters were concerned
that there were no provisions for reuse
or recycle as scrap of noncombustible
containers. The recommended triple
rinsing procedure will clean Group n
containers sufficiently well so that in-
significant contamination occurs when
such containers are legally refilled with
another pesticide belonging to the same
chemical class. Triple rinsing also pre-
pares containers for crushing or shred-
ding and recycle as scrap. Provisions for
this resource conservation step have
been included in § 165.9(b), and specifi-
cally require that adequate rinsing be
undertaken before such reuse or recycle.
Besides these major revisions, several
minor wording changes were made which
did not significantly change the direc-
tion or scope of the recommended
procedures.
It is hoped that these regulations and
recommended procedures will alert all
Federal, State and local government
agencies and private manufacturers,
handlers, and users of pesticides to the
need for proper disposal and storage of
excess pesticides, pesticide containers
and pesticide-related wastes. The United
States Environmental Protection Agency
will follow these recommended proce-
dures In Its own operations. Each office,
laboratory or other facility of the Agency
will conform strictly to these procedures
In the disposal or storage of pesticides
and their containers. State and local
agencies are cautioned against adoption
of these recommended procedures as reg-
ulations without careful study of the en-
vironmental and economic factors ap-
plicable to their own situations, includ-
ing the availability of disposal sites and
facilities.
These regulations and recommended
procedures for disposal and storage of
pesticides and pesticide containers are
Issued under the authority of sections
19(a) and 25(a) of the Federal Insecti-
cide, Fungicide, and Rodenticide Act as
•amended by the Federal Environmental
Pesticide Control Act of 1972 (86 Stat.
955, 977), and section 204 of the Solid
Waste Disposal Act (P.L. 89-272, as
amended by Pi. 91-512).
APRIL 24,1974.
RUSSELL E. TRAIN,
Administrator.
Subpart A—General
Sec.
165.1 Definitions.
166.3 Authorization and scope.
Subpart B—Acceptance Regulation*
165.3 Acceptable pesticides.
185.4 Request for acceptance.
166.5 Delivery.
166.6 Disposal.
Subpart C—Pesticides end Containers
Recommended Procedure*
166.7 Procedures not recommended.
165.8 Recommended procedures for the
disposal of excess pesticides.
166.9 Recommended procedures for the
disposal of pesticide containers
and residues.
166.10 Recommended procedures and cri-
teria for the storage of pesticides
and pesticide containers.
Subpart O—Pesticide-Related Waste
Recommended Procedure*
165.11 Procedures for disposal and stor-
age of pesticide-related ffaste.
AUTHOBTTY: Sees. 19(a) and 25(a) of the
Federal Insecticide. Fungicide, and Rodenti-
cide Act as amended by the Federal Envi-
ronmental Pesticide Control Act of 1973 (86
Stat. 955. 977), and sec. 204 of the Solid
Waste Disposal Act (Pub. L. 89-372 as
amended by Pub. L. 91-613).
Subpart A—General
§ 165.1 Definitions.
As used in this part, all terms not
defined herein shall have the meaning
given them by the Act.
(a) "The Act" means the Federal In-
secticide, Fungicide, and Rodenticide
Act as amended by the Federal Envi-
ronmental Pesticide Control Act of 1972
(Pub. L. 92-516, 86 Stat. 973).
(b) "Agency" means the U.S. En-
vironmental Protection Agency.
(c) (1) "Administrator" means the
Administrator of the Agency, or any offi-
cer or employee thereof to whom author-
ity has been heretofore delegated or to
whom authority may hereafter be del-
egated, to act In his stead.
(2) "Regional Administrator" means
the Administrator of a Regional Office of
the Agency or his delegatee.
(d) "Adequate storage" means placing
of pesticides in proper containers and in
safe areas as per § 165.10 as to minimize
the possibility of escape which could
result In unreasonable adverse effects
on the environment.
(e) "Complete destruction" of pesti-
cides means alteration by physical or
chemical processes to inorganic forms.
(f) "Container" means any package,
can, bottle, bag, barrel, drum, tank, or
other containing-device (excluding spray
applicator tanks) used to enclose a pes-
ticide or pesticide-related waste.
(g) "Decontamination/detoxification"
means processes which will convert pes-
ticides into nontoxic compounds.
(h) "Degradation products" means
those chemicals resulting from partial
decomposition or chemical .breakdown of
pesticides.
(i) "Diluent" means the material
added to a pesticide by the user or manu-
facturer to reduce the concentration of
active ingredient in the mixture.
FEDERAL ftEGISTEt, VOL 39, NO. 85—WEDNESDAY, MAY 1, 1974
217
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15238
RULES AND REGULATIONS
(J) "Encapsulate" means to seal a pes-
ticide, and its container if appropriate,
in an Impervious container made of
plastic, glass, or other suitable material
which will not be chemically degraded
by the contents. This container then
should be sealed within a durable con-
tainer made from steel, plastic, concrete,
or other suitable material of sufficient
thickness and strength to resist physical
damage during and subsequent to burial
or storage.
(k) "Heavy metals" means metallic
elements of higher atomic weights, in-
cluding but not limited to arsenic, cad-
mium, copper, lead, mercury, manganese,
zinc, chromium, tin, thallium, and
selenium.
(1) "imminent hazard" means a sit-
uation which exists when the continued
use of a pesticide during the time re-.
quired .. for cancellation proceedings
would be likely to result in unreasonable
adverse effects on the environment or
will Involve unreasonable hazard to the
survival of a species declared endangered
by the Secretary of the Interior under
Public Law 91-135.
(m) "Ocean dumping*' means the dis-
posal of pesticides in or on the oceans
and seas, as defined in P. L. 92-532.
(n) "Open burning" means the com-
bustion of a pesticide or pesticide con-
tainer in any fashion, other Chan
Incineration.
(o) "Open dumping" means the plac-
ing of pesticides or containers in a land
site in a manner which does not protect
the environment and is exposed to the
elements, vectors, and scavengers. •
(p) "Pesticide" means (1) any sub-
stance or mixture of substances intended
for preventing, destroying, repelling, or
mitigating any pest, or (2) any sub-
stance or mixture of substances Intended
for use as a plant regulator, defoliant,
or desiccant.
(1) "Excess pesticides" means all
pesticides which cannot be legally sold
pursuant to the Act or which are to be
discarded.
(2) "Organic pesticides" means car-
bon-containing substances used as pes-
ticides, excluding metallo-organic com-
pounds.
(3) "Inorganic pesticides" means non-
carbon-containing substances used as
pesticides.
(4) "Metallo-organic pesticides"
mpanq & class of organic pesticides con-
taining one or more metal or metalloid
atoms in the structure.
(q) "Pesticide-related wastes" means
an pesticide-containing wastes or by-
products which are produced in the man-
ufacturing or processing of a pesticide
and which are to be discarded, but which,
pursuant to acceptable pesticide manu-
facturing or processing operations, .are
not ordinarily a part of or contained
within an industrial waste stream dis-
charged into a sewer or the waters of a
state.
(r) "Pesticide Incinerator" means any
installation capable of the controlled
combustion of pesticides, at a tempera-
ture of 1000-C <1832°F) for two seconds
dwell time in the combustion zone, or
lower temperatures and related' dwell
times that will assure complete conver-
sion of the specific pesticide to inorganic
gases and solid ash residues. Such in-
stallation complies with the Agency
Guidelines for the Thermal Processing
of Solid Wastes as prescribed in 40 CFR
Part 240.
(s) "Safe disposal" means discarding
pesticides or containers in a permanent
manner so as to comply with these pro-
posed procedures and so as to avoid un-
reasonable adverse effects on the en-
vironment.
(t) "Sanitary landfill" means a dis-
posal facility employing an engineered
method of disposing of solid wastes on
land In a manner which minimizes en-
vironmental hazards by spreading the
solid wastes in thin layers, compacting
the solid wastes to the smallest practical
volume, and applying cover material at
the end of each working day. Such fa-
cility complies with the Agency Guide-
lines for the Land Disposal of Solid
Wastes as prescribed in 40 CFR Part 241.
(u) "Scrubbing" means the washing
of impurities from any 'process gas
stream.
is published pursuant to Section
204 of the Solid Waste Disposal Act (P.L.
89-272 as amended by Pi. 91-512) which
authorizes the Administrator to make
information available and to make rec-
ommendations concerning the disposal
and handling of wastes.
(b) Regulations for acceptance for
safe disposal of pesticides canceled under
section 6
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RULES AND REGULATIONS
15239
with due regard to the protection of sur-
face and sub-surface waters.
(f) Aa a general guideline, the owner
of excess pesticides should first exhaust
the two following avenues before under-
taking final disposal:
(1) Use for the purposes originally in-
tended, at the prescribed dosage rates,
providing these are currently legal un-
der all Federal, State, and local laws and
regulations.
(2) Return to the manufacturer or
distributor for potential re-labelling,
recovery of resources, or reprocessing
into other materials. Transportation
must be in accordance with all currently
applicable U.S. Department of Trans-
portation regulations, including those
prescribed in 49 CFR Parts 170-179 and
397, 46 CFR Part 146, and 14 CFR Part
103. The "for hire" transportation of un-
registered pesticides across state lines
may be subject to the Interstate Com-
merce Commission's economic regula-
tions (49 U.S.C. 1 et seq. for rail
carriers; 306, 307, and 309 for motor car-
riers; and 909 for domestic water car-
riers), and the Commission should be
contacted in case of doubt.
NOTE: Some excess pesticides may be suit-
able for export to a country where use of the
pesticide Is legal. All pesticides so exported
should be In good condition and packed ac-
cording to specifications of the foreign pur-
chaser, and must be transported to the port
of embarkation in accordance with all De-
partment of Transportation regulations. All
shipments should be in confonnance with
section I7(a) of the Act.
(g) To provide documentation of ac-~
tual situations, all accidents or incidents
involving the storage or disposal of pesti-
cides, pesticide containers, or pesticide-
related wastes should be reported to the
appropriate Regional Administrator.
Subpart B—Acceptance Regulations
§ 165.3 Acceptable pesticides.
The Administrator will- accept for safe
disposal those pesticides the registrations
of which have been canceled, after first
having been 'suspended to prevent an
imminent hazard during the time re-
quired for cancellation proceedings as
specified in section 6(c) of the Act. How-
ever, no other pesticides will be accepted
pursuant to section 19 (a) of the Act, and
nothing herein shall obligate the Federal
Government to own or operate any dis-
posal faculty.
§ 165.4 Request for acceptance.
(a) Before the owner of such a pesti-
cide requests acceptance by the Admin-
istrator for disposal, he shall make every
reasonable effort to return the material
to either Its manufacturer, distributor.
or to another agent capable of using the
material,
(b) If such an effort Is unsuccessful,
the following procedure shall be used by
the owner of a suspended pesticide to
request acceptance by the Administra-
tor:
(1) The owner of such a pesticide
must make a formal request for accept-
ance, In writing, to the Regional Admin-
istrator for the area where such pesti-
cides are located.
(2) Records and data pertaining to
the amount, location, physical form, type
and condition of containers, and date of
manufacture or purchase of individual
lots must be submitted. Certification that
the owner of the suspended pesticide has
made every reasonable effort to return
the material to the manufacturer, dis-
tributor of the pesticide, or to other
agents capable of re-labeling, recover-
ing, recycling or reprocessing the ma-
terial and has been refused on the basis
of technological infeaslbility, must also
be submitted.
§ 165.5 Delivery.
. If it is found that a canceled pesticide
meets the requirements for acceptance,
the Regional Administrator will confer
with the owner for purposes of arranging
a mutually convenient location for ac-
ceptance of individual lots of such can-
celed pesticides. Transportation to the
acceptance location will be. the respon-
sibility of, and transportation costs will
be borne by, the owner of the pesticide.
§ 165.6 Disposal.
Following such acceptance, the Re-
gional Administrator will cause the dis-
posal or storage of such pesticide as ap-
propriate, in accordance with the proce-
dures outlined in subparts A and C of this
part.
Subpart C—Pesticides and Containers
§ 165.7 Procedures not recommended.
No person should dispose of or store
(or receive for disposal or storage) any
pesticide or dispose of or store any pesti-
cide container or pesticide container resi-
due:
(a) In a manner inconsistent with its
label or labeling.
(b) So as to cause or allow open dump-
Ing of pesticides or pesticide containers.
(c) So as to cause or allow open burn-
big of pesticides or pesticide containers;
except, the open burning by the user of
small quantities of combustible contain-
ers formerly containing organic or
metallo-organlc pesticides, except or-
ganic mercury, lead, cadmium, or arse-
nic compounds, is acceptable when al-
lowed'by State and local regulations.
(d) So as to cause or allow water
dumping or ocean dumping, except In
confonnance with regulations developed
pursuant to the National Marine Protec-
tion, Research and Sanctuaries Act of
1972 (Pub. L. 92-532), and to Sections
304, 307, and 311 of the Federal Water
Pollution Control Act as Amended (Pub.
L. 92-500).
(e) So as to violate any applicable
Federal or State pollution control
standard.
(f) So as to violate any applicable pro-
visions of the Act.
g 165.8 Recommended procedures for
the disposal of pesticides.
Recommended procedures for the
disposal of pesticides are given below:
(a) Organic pesticides, (except or-
ganic mercury, lead, cadmium, and ar-
senic compounds which are discussed in
paragraph (c) of this section) should
be disposed of according to the following
procedures:
(1) Incinerate In a pesticide inciner-
ator at the specified temperature/dwell
time combination, or at such other lower
temperature and related dwell time that
will cause complete destruction of the
pesticide. As a minimum It should be
verified that all emissions meet the re-
quirements of the Clean Air Act of 1970
(42 U.S.C. 1857 et seq.) relating to gase-
ous emissions: specifically any perform-
ance regulations and standards pro-
mulgated under sections 111 and 112
should be adhered to. Any liquids,
sludges, or solid residues generated
should be disposed of in accordance with
all applicable Federal, State, and local
pollution control requirements. Munici-
pal solid waste incinerators may be used
to incinerate excess pesticides or pesti-
cide containers provided they meet the
criteria of a pesticide Incinerator and
precautions are taken to ensure proper
operation.
(2) If appropriate incineration facili-
ties are not available, organic pesticides
may be disposed of by burial in a spe-
cially designated landfill. Records to lo-
cate such buried pesticides within the
landfill site should be maintained.
(3) The environmental impact of the
soil injection method of pesticide dis-
posal has not been clearly defined na-
tionally, and therefore this disposal
method should be undertaken only with
specific guidance. It is recommended that
advice be requested from the Regional
Administrator In the region where the
material will be disposed of prior to
undertaking such disposal by this
method.
(4) There are chemical methods and
procedures which will degrade some pes-
ticides to forms which are not hazardous
to the environment. However, practical
methods are not available for an groups
of pesticides. Until a list of such meth-
ods is available, it is recommended that
advice be requested from the Regional
Administrator in the region where the
material will be disposed of prior to
undertaking disposal by such method.
(5) If adequate incineration facilities,
specially designated landfill facilities, or
other approved procedures are not avail-
able, temporary storage of pesticides for
disposal should be undertaken. Stor-
age facilities, management procedures,
safety precautions and fire and explo-
sion control procedures should conform
to those set forth in 5165.10.
(6T The effects of subsurface emplace-
ment of liquid by well injection and the
fate of Injection materials are uncertain
with available knowledge, and could re-
sult In serious environmental damage re-
quiring complex and costly solutions on
a long-term basis. Well Injection should
not be considered for pesticide disposal
unless all reasonable alternative meas-
ures have been explored and found less
satisfactory In terms of environmental
protection. As noted In the Administra-
tor's Decision Statement No. 5, dated
February 6, 1973, the Agency's policy is
to oppose well Injection of fluid pesticides
FSDHAL UOISTER, VOL. 39, NO. 85—WEDNESDAY, MAY 1, 1974
219
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RULES AND REGULATIONS
"without strict controls and a clear dem-
onstration that such emplacement will
not Interfere with present or potential
use of the subsurface environment, con-
taminate ground water resources or
otherwise damage the environment."
Adequate pre-lnjection tests, provisions
for monitoring the operation and the en-
vironmental effects, contingency plans
to cope with well failures, and provisions
for plugging- Injection wells when aban-
doned should be made. The Regional
Administrator should be advised of each
operation.
(b) Metallo-orcanlc pesticides (except
organic mercury, lead, cadmium, or ar-
senic compounds which are discussed in
paragraph (c) of this section), should
be disposed of according to the follow-
ing procedures:
(1) After first subjecting such com-
pounds to an appropriate chemical or
physical treatment to recover the heavy
metals from the hydrocarbon structure,
Inclnearate in a pesticide incinerator as
described in paragraph (a) (1) of this
section.
(2) If appropriate treatment and in-
cineration are not available, bury in a
specially designated landfill as noted In
paragraph (a) (2) of this section.
(3) Disposal by soil injection of me-
tallo-organlc pesticides should be under-
taken only In accordance with the proce-
dure set forth In paragraph (a) (3) of
this section.
(4) Chemical degradation methods and
procedures that can be demonstrated to
provide safety to public health and the
environment should be undertaken only
as. noted In paragraph (a) (4) of this
section.
(5) If adequate disposal methods as
listed above, in this section are not avail-
able, the pesticides should be stored ac-
cording to the procedures In § 165.10 un-
til disposal facilities become available.
(6) Well Injection of metallo-organlc
pesticides should' be undertaken only in
accordance with the procedures set forth
in paragraph 165.8(a) (6) of this section.
(c) Organic mercury, lead, cadmium,
arsenic, and all Inorganic pesticides
should be disposed of according to the
following procedures: /
(1) Chemically deactivate the pesti-
cides- by conversion to non-hazardous
compounds, and recover the heavy metal
resources. Methods that are appropriate
will be described and classified accord-
Ing to their applicability to the different
groups of pesticides. Until a list of prac-
tical methods is available, however, each
use of such procedures should be under-
taken only as noted In paragraph 16S.8
(a) (4) of this, section.
(2). If chemical deactivation facilities
are not available, such pesticides should
be encapsulated and burled in a specially
designated landfill. Records sufficient to
permit location for retrieval should be
maintained*
(3) If none of the above options Is
available, place in suitable containers
(if necessary.) and provide temporary
storage until such time as- adequate dis-
posal facilities or procedures are avail-
able. The general criteria for acceptable
storage are noted In S 165.10.
§ 165.9 Recommended procedures for
the disposal of pealicide containers
and residues.
(a) Group I Containers. Combustible
containers which formerly contained
organic or metallo-organlc pesticides,
except organic mercury, lead, cadmium,
or arsenic compounds, should be dis-
posed of in a pesticide incinerator, or
buried in a specially designated landfill,
as noted in § 165.8(a); except that small
quantities of such containers may be
burned in open fields by the user of the
pesticide when such open burning is per-
mitted by State and local regulations, or
buried singly by the user in open fields
with due regard for protection of surface
and sub-surface water.
(b) Group // Containers. Non-com-
bustible containers which formerly con-
tained organic or metallo-organlc pesti-
cides, except organic mercury, lead, cad-
mium, or arsenic compounds, should first
be triple-rinsed. Containers in good con-
dition may then be returned to the pesti-
cide manufacturer or formulator, or
drum reconditloner for reuse with the
same chemical class of pesticide pre-
viously contained providing such reuse
is legal under currently applicable U.S.
Department of Transportation regula-
tions including those set forth in 49 CFR
173.28. Other rinsed metal containers
should be punctured to facilitate drain-
age prior to transport to a facility for
recycle as scrap metal or for disposal. All
rinsed containers may be crushed and
disposed of by burial In a sanitary land-
fill, in conformance with State and local
standards or buried in the field by the
user of the pesticide. Unrinsed contain-
ers should be disposed of in a specially
designated landfill, or subjected to In-
cineration in a pesticide incinerator.
(c) Group III Containers. Containers
(both combustible and noncombustlble)
which formerly contained organic mer-
cury, lead, cadmium, or arsenic or in-
organic pesticides and which have been
triple-rinsed and'punctured to facilitate
drainage, may be disposed of in a sani-
tary ip.tylfl" Such containers which are
not rinsed should be encapsulated and
buried In a specially designated landfill.
(d) Residue disposal. Residues and
rinse liquids should be added to spray
mixtures In the field. If not, they should
be disposed of in the manner prescribed
for each specific type of pesticide as set
forth In 5 165.8.
§ 165.10 Recommended procedures and
criteria for storage of pesticides and
pesticide containers.
(a) General. (1) Pesticides and excess
pesticides and their containers whose un-
controlled release into the environment
would cause• unreasonable adverse ef-
fects on the environment should be stored
only In facilities where due regard has
been given to the hazardous nature of the
pesticide, site selection; protective en-
closures, and operating procedures, and
where adequate measures are taken to
assure personal safety, accident preven-
tion, and detection of potential environ-
mental damages. These storage proce-
dures and criteria should be observed at
sites and facilities where pesticides and
excess pesticides (and their containers)
that are classed as highly toxic or mod-
erately toxic and are required to bear
the signal words 'DANGER, POISON, or
WARNING, or the skull and crossbones
symbol on the label are stored. These pro-
cedures and criteria are not necessary at
facilities where most pesticides registered
for use in the home and garden, or pestl-
cldes classed as slightly toxic (word
CAUTION on the label) are stored. All
faculties where pesticides which are or
may in the future be covered by an ex-
perimental use permit or other special
permit are stored should be in conform-
ance with these procedures and criteria.
(2) Temporary storage of highly toxic
or moderately toxic pesticides for the
period immediately prior to, and of the
quantity required for a single application,
may be undertaken by the user at iso-
lated sites and facilities where flooding is
unlikely, where provisions are made to
prevent unauthorized entry, and where
separation from water systems and build-
ings is sufficient to prevent contamina-
tion by runoff, percolation, or wind-blown
particles or vapors.
(b) Storage sites. Storage sites should
be selected with due regard to the
amount, toxlcity, and environmental
hazard of pesticides, and the number and
sizes of containers to be handled. When
practicable, sites should be located where
flooding is unlikely and where soil tex-
ture/structure and geologic/hydrologlc
characteristics will prevent the con-
tamination of any water system by run-
off or percolation. Where warranted,
drainage from the site should be con-
tained (by natural or artificial barriers
or dikes), monitored, and if contami-
nated, disposed of as an excess- pesticide
as discussed in 5165.8. Consideration
should also be given to containing wind-
blown pesticide dusts or particles.
(c) Storage facilities. Pesticides
should be stored In a dry, well ventilated,
separate room, building or covered area
where fire protection is provided. Where-
relevant and practicable, the following
precautions should be taken:
(1) The entire storage facility should
be secured by a climb-proof fence, and
doors and gates should be kept locked to
prevent unauthorized entry.
(2) Identification signs should be
placed on rooms, buildings, and fences .to
advise of the contents and'warn of their
hazardous nature, in accordance with
suggestions given in paragraph (g) (1) (1)
of this section.
(3) All items of movable equipment
used for handling pesticides at the
storage site which might be used for
other purposes- should be labeled "con-
taminated with pesticides" and should
not be removed from the site unless thor-
oughly decontaminated.
(4) Provision should be made for de-
contamination of personnel and equip-
ment such aa delivery trucks, tarpaulin
covers, etc. Where feasible, a wash basin,
and shower with a delayed-closing pull
FEDERAL REGISTER, VOL. 39, NO. 83
220
-WEDNESDAY, MAY 1, 1974
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RULES AND REGULATIONS
15241
chain .valve should be provided. All con-
taminated water should be disposed of as
an excess pesticide. Where required, de-
contamination area should be paved or
lined with impervious materials, and
should Include gutters. Contaminated
runoff should be collected, and treated
as an excess pesticide.
(d) Operational procedures. Pesticide
containers should be stored with the
label plainly visible. If containers are not
in good condition when received, the
contents should be placed In a suitable
container and properly relabeled. If dry
excess pesticides are received in paper
bags that are. damaged, the bag and the
contents should be placed in a sound
container that can be sealed. Metal or
rigid plastic containers should be
checked carefully to Insure that the lids
and bungs are tight. Where relevant
and practicable, the following provisions
should be considered:
(1) Classification and separation, (i)
Each pesticide formulation should be
segregated and stored under a sign con-
taining the name of the formulation.
Rigid containers should be stored in an
upright * position and all containers
should be stored off the ground, in an or-
derly way, so as to permit ready access
and Inspection. They should be accumu-
lated in rows or units so that all labels
are visible, and with lanes to provide ef-
fective access. A complete Inventory
should be maintained indicating the
number and identity of containers in
each storage unit. .
. (ii) Excess pesticides and containers
should be further segregated according
to the method of disposal to.ensure that
entire shipments of the same class of
pesticides are disposed of properly, and
that accidental mixing of containers of
different categories does not occur dur-
ing, the removal operation.
'. (2) Container inspection and mainte-
nance. Containers should be checked
regularly for corrosion and leaks. If such
Is found, the container should be trans-
ferred to a sound, suitable, larger con-
tainer and be properly labeled. Materials
such as adsorptive clay, hydrated lime,
and sodium hypochlbrite should be kept
on hand for use as appropriate for the
emergency treatment or detoxification
of spills or leaks. (Specific information
relating to other spill treatment proce-
dures and materials will be published as
' It is confirmed:)
. • (e) Safety precautions. In addition to
precautions specified on the label and in
the labeling, rules for personal safety
and accident prevention similar to
those listed below should be available
in areas where personnel congregate:
. (1) Accident prevention measures. (1)
Inspect all containers of pesticides for
leaks before handling them.
(11) Do not mishandle containers and
thereby create emergencies by careless-
ness.
(ill) Do not permit unauthorized per-
sons in the storage area.
(iv) Do not store pesticides next to
food or feed or other articles Intended
for consumption by humans or animals.
(v) Inspect all vehicles prior to de-
parture, and treat those found to be
contaminated.
(2) Safety measures, (i) Do not store
food, beverages, tobacco, eating utensils,
or smoking equipment in the storage or
loading areas.
(11) Do not drink, eat food, smoke, or
use tobacco in areas where, pesticides
are present.
(iii) Wear rubber gloves while han-
dling containers of pesticides.
(iv) Do not put fingers in mouth or
rub eyes while working.
(v) Wash hands before eating, smok-
ing, or using toilet and immediately after
loading, or transferring pesticides.
(vi) Persons working regularly with
organophosphate and N-alkyl carbamate
pesticides should have periodic physical
examinations, Including chollnesterase
tests.
(f) Protective clothing and respirators.
(1) When handling pesticides which are
in concentrated form, protective cloth-
Ing should be worn. Contaminated gar-
ments should be removed immediately,
and extra sets of clean clothing should
be maintained nearby.
(2) Particular care should be taken
when handling certain pesticides to pro-
tect against absorption through skin, and
inhalation of fumes. Respirators or gas
masks with proper canisters approved
for the particular type of exposure noted
In the label directions, should be used
when such pesticides are handled.
(g) Fire control. (1) Where large
quantities of pesticides are stored, or
where conditions may otherwise warrant,
the owner of stored pesticides should in-
form the local fire department, hospitals,
public health officials, and police depart-
ment in writing of the hazards that such
pesticides may present in the event of a
fire. A floor plan of the storage area indi-
cating where different pesticide classi-
fications are regularly stored should be
provided to the fire department. The fire
chief should be furnished with the home
telephone numbers of (i) the person (s)
responsible for the pesticide storage fa-
cility, (li) the appropriate Regional Ad-
ministrator, who can summon the appro-
priate Agency emergency response team,
(iii) the U.S. Coast Guard, and (iv) the
Pesticide Safety Team Network of the
National Agricultural Chemicals Asso-
ciation.
(2) Suggestions for Fire Hazard Abate-
ment, (l) Where applicable, plainly label
the outside of each storage area with
"DANGER," "POISON," "PESTICIDE
STORAGE" signs. Consult with the local
fire department regarding the use of the
current hazard signal system of the Na-
tional Fire Protection Association.
(ii) Post a list on the outside of the
storage area of the types of chemicals
stored therein. The list should be updated
to reflect changes In types stored.
(3) Suggested Fire Fighting Pre-
cautions, (i) Wear air-supplied breath-
ing apparatus and rubber clothing.
(11) Avoid breathing or otherwise con-
tacting toxic smoke and fumes.
(ill) Wash completely as soon as pos-
sible after encountering smoke and
fumes.
(Iv) Contain the water used. In fire
fighting within the storage site drainage
system.
(v) Fireman should take chollnester-
ase tests after fighting a fire involving
organophosphate or N-alkyl carbamate
pesticides, If they have been heavily ex-
posed to the smoke. Baseline cholines-
terase tests should be part of the regular
physical examination for such firemen.
(vi) Evacuate persons near such fires
who may come in contact with smoke or
fumes or contaminated surfaces.
(h) Monitoring. An environmental
monitoring system should be considered
In the vicinity of storage facilites.
Samples from the surroundng ground
and surface water, wildlife, and plant
environment, as appropriate, should be
tested in a regular program to assure
minimal environmental Insult. Analyses
should be performed according to "Of-
ficial Methods of the Association of
Official Analytical Chemists (AOAC),"
and such other methods and procedures
as may be suitable.
Subpart D—Pesticide-Related Wastes
§ 165.11 Procedures for disposal and
storage of pesticide-related wastes.
(a) In general all pesticide-related
wastes should be disposed of as excess
pesticides in accordance with the pro-
cedures set forth in }§ 165.7 and 165.8.
Such wastes should not be disposed of
by addition to an Industrial effluent
stream if not ordinarily a part of or con-
tained within such industrial effluent
stream, except as regulated by and In
compliance with effluent standards es-
tablished pursuant to sections 304 and
307 of the Federal Water Pollution Con-
trol Act as amended.
(b) Pesticide-related wastes which are
to be stored should be managed in ac-
cordance with the provisions of § 165.10.
[FR Doc.74-9911 Filed 4-30-74;8:46 am]
ROERAl REOISTFR, VOl. ?9, HO. 8S--WEDN550Ar, MAY 1, 1974
221
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APPENDIX C
SITE VISITS RELATED TO HAZARDOUS AND TOXIC MATERIAL DISPOSAL
Appendix C lists sites visited by R» R. Wilkinson and F. C. Hopkins tc
gather information on hazardous and toxic material disposal technology and
research. The compilation presents the following information:
* Site visited (company, location)
* Date of visit
* Person(s) interviewed
* Technology discussed
* Application to pesticides or other hazardous waste material
!• Atomics International Division
Rockwell International
8900 DeSoto Road
Canoga Park, California
213-341-1000
September 28, 1977
Dr. Sam Yosim, Chemist
Dr. Al J. Darnell, Chemist
Mr. Russell B. Hunter, Marketing Representative
Molten salt bath
Pesticide incineration
2. Combustion Power Company, Inc.
Subsidiary of Weyerhaeuser Company
1346 Willow Road
Menlo Park, California
415-324-4744
September 30, 1977
Mr. Dale Moody, Senior Project Engineer
1 Fluidized bed incinerators
Herbicide Orange incineration
222
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3« Envirotech Corporation
EIMCO BSP Division
One Davis Drive
Belmont, California
415-592-4060
- September 29, 1977
Mr. Sid Howard, Marketing Manager
Mr. John Gibbs, Group Product Manager
Multiple hearth furnaces
Incineration of PCB's, DDT and 2,4,5-T
4o Iowa State University
Horticultural Research Station
Ames, Iowa
515-294-2751
July 5, 1977
Dr. Charles Hall, Project Leader
'Mr. Loras Freibuirger, Research Technician
Disposal pit technology
Pesticide biodegradation
5. Lockheed Palo Alto Research Laboratory
3251 Hanover Street
Palo Alto, California
415-493-4411
September 29, 1977
Dr. Lionel Bailin, Chemise
Dr. Barry Hertzler, Chemist
Dr. Ernest Littauer, Manager Chemistry Section
Microwave plasma destruction unit
Destruction of pesticides and other hazardous materials
6. The Marquardt Company
1655 Saticoy Street
Van Nuys, California
213-781-2121
September 27, 1977
Mr. Robert Babbitt, Manager Process Engineering
SUE®modified jet engine combustion unit
DDT and Herbicide Orange incineration
7. MB Associates, Inc.
Bellinger Canyon Road
San Ramon, California
415-837-7201
September 30, 1977
Mr. Ray Tenzer, Combustion Engineer
223
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Mr. Ben Ford, Combustion Engineer
Rotary kilns
Incineration of oil and other hazardous waste materials
8. Oak Ridge National Laboratory
Oak Ridge, Tennessee
615-483-8611
October 11, 1977
Dr. Charles Scott, Associate Director Chemical Technology
Division
Dr. W. W« Pitt, Jr., Manager Biotechnology and Environmental
and Groups Leader, Environmental Monitoring
Dr. S. £• Shumate II, Group Leader Bioengineering R&D
Mr. Charles W. Rancher, Group Leader, Bioprocess Engineer
Fluidized bed bacteriological reactor
Bacterial degradation of hazardous wastes
9. SCS Engineers, Inc.
4014 Long Beach Boulevard
Long Beach, California
213-426-9544
September 28, 1977
Dr. Tan Phung, Chemical Engineer
Dr. Warren Hansen, Chemical Engineer
Dr. David Ross, Chemical Engineer
Soil cultivation techniques as applied to pesticides and
other hazardous materials
224
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