United States
Environmental Protection
Agency
Office of Research and
Development
Washington DC 20460
EPA/540/R-95/502
July 1997
&EPA
Sonotech, Inc.
Frequency-Tunable Pulse
Combustion System
(Cello® Pulse Burner)
Innovative Technology
Evaluation Report
4 me*^3s^.-^e-;'>>&.-
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SUPERFUND INNOVATIVE
TECHNOLOGY EVALUATION
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EPA/540/R-95/ 502
July 1997
Sonotech, Inc. Frequency-Tunable Pulse
Combustion System (Cello® Pulse Burner)
Innovative Technology
Evaluation Report
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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Notice
This document has been prepared for the U.S. Environmental Protection Agency (EPA) Superfund
Innovative Technology Evaluation (SITE) program under Contract No. 68-C5-0037. This docu-
ment has been subjected to EPA's peer and administrative reviews and has been approved for
publication as an EPA document. Mention of trade names or commercial products does not consti-
tute an endorsement or recommendation for use.
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Foreword
The EPA is charged by Congress with protecting the Nation's land, air, and water resources. Under
a mandate of national environmental laws, the Agency strives to formulate and implement actions
leading to a compatible balance between human activities and the ability of natural systems to
support and nurture life. To meet these mandates, EPA's research program is providing data and
technical support for solving environmental problems today and building a science knowledge
base necessary to manage our ecological resources wisely, understand how pollutants affect our
health, and prevent or reduce environmental risks in the future.
The National Risk Management Research Laboratory (NRMRL) is the EPA center for investigation of
technical and management approaches for reducing risks from threats to human health and the envi-
ronment. The focus of the NRMRL research program is on methods for the prevention and control of
pollution to air, land, water, and subsurface resources; protection of water quality in public water
systems; remediation of contaminated sites and groundwater; and prevention and control of indoor air
pollution. The goals of this research effort are to catalyze development and implementation of innova-
tive, cost-effective environmental technologies; develop scientific and engineering information needed
by EPA to support regulatory and policy decisions; and provide technical support and information
transfer to ensure effective implementation of environmental regulations and strategies.
This publication has been produced as part of the NRMRL strategic, long-term research plan. It is
published and made available by the EPA Office of Research and Development to assist the user
community and to link researchers with their clients.
E. Timothy Oppelt, Director
National Risk Management Research Laboratory
111
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Abstract
Sonotech, Inc. (Sonotech) of Atlanta, GA, has developed a pulse combustion burner technology
that claims to offer benefits when applied in a variety of combustion processes. The technology
incorporates a combustor that can be tuned to induce large-amplitude acoustic or sonic pulsations
inside combustion process units, such as boilers or incinerators. This report summarizes the find-
ings of an evaluation of the pulse combustion burner system developed by Sonotech. The Cello®
Pulse Burner system was demonstrated in the autumn of 1994 at the EPA Incineration Research
Facility (IRF) in Jefferson, AR, under the EPA SITE program.
The information is intended for remedial managers, environmental consultants, and other poten-
tial users who may consider using the technology to treat Superfund and Resource Conservation
and Recovery Act of 1976 (RCRA) hazardous wastes. It presents an overview of the SITE pro-
gram, describes the Sonotech system, and lists key contacts; discusses information relevant to the
technology's application, including an assessment of the technology related to the nine feasibility
study evaluation criteria, potential applicable environmental regulations, and operability and limi-
tations of the technology; summarizes the costs associated with implementing the technology;
presents the waste characteristics, demonstration approach, demonstration procedures, and the
results and conclusions of the demonstration; summarizes the technology status; and includes a
list of references. The Appendix presents case studies provided by the developer.
IV
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Contents
Foreword iij
Abstract iv
List of Figures vii
List of Tables viii
Acronyms and Abbreviations ix
Acknowledgements xii
Executive Summary ES-1
1.0 Introduction 1
1.1 The SITE Program 1
1.2 Innovative Technology Evaluation Report 1
1.3 Project Description 1
1.4 Technology Description 2
1.5 Key Contacts 2
2.0 Technology Applications Analysis 4
2.1 Feasibility Study Evaluation Criteria 4
2.1.1 Overall Protection of Human Health and the Environment 4
2.1.2 Compliance with ARARs 5
2.1.3 Long-Term Effectiveness and Permanence 5
2.1.4 Reduction of Toxicity, Mobility, or Volume through
Treatment 5
2.1.5 Short-Term Effectiveness 5
2.1.6 Implementability 6
2.1.7 Costs 6
2.1.8 State Acceptance 6
2.1.9 Community Acceptance 6
2.2 Technology Performance Regarding ARARs 6
2.2.1 Comprehensive Environmental Response, Compensation,
and Liability Act 6
2.2.2 Resource Conservation and Recovery Act 9
2.2.3 Clean Air Act 10
2.2.4 Toxic Substances Control Act 10
2.2.5 Occupational Safety and Health Administration
Requirements 10
2.2.6 Technology Performance Regarding ARARs During
the Demonstration 10
2.3 Operability of the Technology 11
2.4 Applicable Wastes 11
2.5 Key Features of the Sonotech Cello® Pulse Combustion System 11
2.6 Availability and Transportability of Equipment 11
2.7 Materials-Handling Requirements 11
2.8 Site-Support Requirements 12
2.9 Limitations of the Technology 12
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Contents (continued)
3.0 Economic Analysis 14
3.1 Introduction 14
3.2 Issues and Assumptions 14
3.2.1 Equipment and Operating Parameters 14
3.2.2 Additional Assumptions 15
3.2.3 Financial Calculations 15
3.3 Cost Categories 15
3.3.1 Site Preparation Costs 15
3.3.2 Permitting and Regulatory Costs 15
3.3.3 Mobilization and Start-Up Costs 15
3.3.4 Equipment Costs 16
3.3.5 Labor Costs 16
3.3.6 Supply Costs 16
3.3.7 Utility Costs 16
3.3.8 Effluent Treatment and Disposal Costs 16
3.3.9 Residual Waste Shipping and Handling Costs 16
3.3.10 Analytical Service Costs 16
3.3.11 Equipment Maintenance Costs 16
3.3.12 Demobilization Costs 16
3.4 Conclusions of Economic Analysis 16
4.0 Treatment Effectiveness 18
4.1 Demonstration Objectives and Approach 18
4.2 Demonstration Procedures 19
4.2.1 Waste Preparation for the Demonstration 19
4.2.2 Demonstration Design 20
4.2.3 Sampling and Analysis Program 20
4.2.4 Quality Assurance and Quality Control Program 24
4.3 Demonstration Results and Conclusions 24
4.3.1 Operating Conditions 24
4.3.2 Results and Discussion 32
4.3.3 Data Quality 38
4.3.4 Conclusions 38
5.0 Technology Status 40
5.1 Introduction 40
5.2 Completed Demonstrations 40
5.3 Ongoing Projects 40
6.0 References 42
Appendix
Case Studies 43
VI
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List of Figures
1 Sonotech Cello® Pulse Combustion Burner System Fitted to the IRF RKS 12
2 Key Features of the Sonotech Cello® Pulse Combustion System 13
3 Block Diagram of Rotary Kiln System Sampling Locations, Types, and Methods 21
4 Generalized Flue Gas and CEM Gas Flow Schematic 23
A-l A schematic of the spray nozzle configuration used in Task 1 to investigate
the effect of pulsations on water spray 44
A-2 A schematic of the evaporator setup used in Task 2 to investigate the effect
of pulsations upon water spray evaporation 45
A-3 Comparison of limestone calcination rates attained in 1 SOOT pulsing and
steady-state flow tests 47
A-4 Percentages of calcination attained by limestone having different initial
weights in 20 minute steady and pulsing test at a 1720°F 47
A-5 Temperature rise at the center of the cylinder under pulsating and steady
heating conditions 48
vn
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List of Tables
Number
Page
1 Feasibility Study Evaluation Criteria for the Sonotech Technology 4
2 Potential Federal ARARs for the Sonotech Pulse Combustion System 7
3 Costs Associated with the Sonotech Technology 15
4 Equipment Depreciation 16
5 Worksheet 17
6 Target Analytes 25
7 Test Program Sample Analysis Summary 25
8 Analytical Protocols 28
9 Target Feedrates 30
10 IRF RKS Air Pollution Control System Operating Parameters 30
11 Measured Incinerator Operating Parameters 31
12 Operating Data and Results 32
13 Concentrations of Volatile and Semivolatile Organic Constituents
in Feed Materials 33
14 Concentrations of Metals in Feed Materials 34
15 Summary of Gaseous Emissions Data 35
16 NOx Emissions 35
17 Summary of Test Program POHC DREs 36
18 Metals Distribution Results 37
19 TCLP Results of Feed, Ash, and Scrubber Liquor 37
20 Average Dioxin and Furan Toxicity Equivalent Emissions 38
A-l Evaporation Efficiencies for Task 1 45
A-2 Task 2 Maximum Water Flowrates to Completely Evaporate Water 46
A-3 Summary of Data Measured in Sonotech Scoping Runs 49
A-4 Benefits Provided by the Sonotech System 50
Vlll
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Acronyms and Abbreviations
Acurex Acurex Environmental Corporation
AEERL Air and Energy Engineering Research Laboratory
APCD Air pollution control device
APCS Air pollution control system
ARAR Applicable or relevant and appropriate requirement
ATTIC Alternative Treatment Technology Information Center
BIF Boilers and industrial furnace
BTEX Benzene, toluene, ethylbenzene, and xylenes
Btu British thermal unit
Btu/hr British thermal unit per hour
Btu/lb British thermal unit per pound
C Carbon
CAA Clean Air Act
CaCO3 Calcium carbonate
CaO Calcium oxide
°C Degree Celsius
CEM Continuous emissions monitor
CERCLA Comprehensive Environmental Response, Compensation, and
Liability Act
CERI Center for Environmental Research Information
CFR Code of Federal Regulations
Cl Chlorine
CO Carbon monoxide
CO2 Carbon dioxide
CVAAS Cold Vapor Atomic Absorption Spectroscopy
dB Decibel
DoD U.S. Department of Defense
DOE U.S. Department of Energy
DRE Destruction and removal efficiency
dscf/hr Dry standard cubic foot per hour
EPA U.S. Environmental Protection Agency
°F Degree Fahrenheit
ft3 Cubic foot
gc/ms Gas Chromatography/Mass Spectrometry
GFAAS Graphite Furnace Atomic Absorption Spectroscopy
grain/dscf Grain per dry standard cubic foot
g/hr Gram per hour
gpm Gallon per minute
GRI Gas Research Institute
H Hydrogen
HDPE High-density polyethylene
HEPA High-efficiency particulate air
Hz Hertz or cycles per second
1C Ion chromatography
ICP Inductively coupled argon plasma Spectroscopy
IRF U.S. EPA Incineration Research Facility
IX
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Acronyms and Abbreviations (continued)
ITER Innovative Technology Evaluation Report
kBtu/hr Thousand British thermal units per hour
kg Kilogram
kg/hr Kilograms per hour
kPa Kilopascal
kW Kilowatt
kWh Kilowatt hour
Ib/hr Pound per hour
LDR Land disposal restrictions
L/min Liter per minute
m3 Cubic meter
MBtu Million British thermal units
MDL Method detection limit
mg/dscm Milligram per dry standard cubic meter
mg/hr Milligram per hour
mg/kg Milligram per kilogram
mg/L Milligrams per liter
MGP Manufactured gas plant
MJ Megajoule
MJ/kg Megajoule per kilogram
MS Matrix spike
MSD Matrix spike duplicate
mv Millivolt
N Nitrogen
NAAQS National Ambient Air Quality Standards
ng/dscm Nanogram per dry standard cubic meter
NOx Nitrogen oxide
NRMRL National Risk Management Research Laboratory
NSPS New Source Performance Standard
O3 Elemental oxygen
ORD U.S. EPA Office of Research and Development
OSHA Occupational Safety and Health Administration
OSWER U.S. EPA Office of Solid Waste and Emergency Response
PAH Polynuclear aromatic hydrocarbon
PCDD Polychlorinated dibenzo-p-dioxin
PCDF Polychlorinated dibenzofuran
PCB Polychlorinated biphenyl
PE Polyethylene
Peoples Peoples Natural Gas Company Superfund site in Dubuque, IA
POHC Principal organic hazardous constituent
PPE Personal protective equipment
ppm Part per million
PRC PRC Environmental Management, Inc.
PSD Prevention of significant deterioration
QA Quality assurance
QAPP Quality assurance project plan
QC Quality control
RCRA Resource Conservation and Recovery Act of 1976
RKS Rotary kiln incineration system
RPD Relative percent difference
rpm Revolutions per minute
S Sulfur
SARA Superfund Amendments and Reauthorization Act of 1986
SBIR Small Business Innovative Research
SITE Superfund Innovative Technology Evaluation
Sonotech Sonotech, Inc. of Atlanta, GA
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Acronyms and Abbreviations (continued)
SVOC Semivolatile organic compound
TCLP Toxicity characteristic leaching procedure
TEF Toxicity equivalency factors
TEQ 2,3,7,8-TCDD equivalents
TOC Total organic carbon
TSCA Toxic Substances Control Act
TSD Treatment, storage, or disposal
TRL Target reporting limit
TUHC Total unburned hydrocarbons
Hg/dscm Microgram per dry standard cubic meter
pg/L Microgram per liter
VISITT Vendor Information System for Innovative Treatment Technologies
VOC Volatile organic compound
VOST Volatile organic sampling train
2,3,7,8-TCDD 2,3,7,8-Tetrachlorodibenzo-para-dioxin
XI
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Acknowledgements
This report was prepared under the direction of Ms. Marta K. Richards, the EPA SITE project
manager with NRMRL in Cincinnati, OH. This report was prepared by Mr. Anthony Gardner,
Dr. Kenneth Partymiller, Mr. Jeffrey Swano, and Ms. Regina Bergner of PRC Environmental
Management, Inc. (PRC), and Drs. Shyam Venkatesh and Larry Waterland of Acurex Environ-
mental Corporation (Acurex). Contributors and reviewers for this report included Ms. Marta K.
Richards of NRMRL and Mr. Zin Plavnik of Sonotech, Inc.
xn
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Executive Summary
This report summarizes the findings of an evaluation of the
pulse combustion burner system developed by Sonotech. The
Cello® Pulse Burner system was demonstrated at the EPA IRF
in Jefferson, AR, under the EPA SITE program. The Sonotech
system was demonstrated in the autumn of 1994.
The purpose of this Innovative Technology Evaluation Re-
port (ITER) is to present and summarize information from the
SITE demonstration of the Sonotech system. The information is
intended for remedial managers, environmental consultants, and
other potential users who may consider using the technology to
treat Superfund and RCRA hazardous wastes. Section 1.0 pre-
sents an overview of the SITE program, describes the Sonotech
system, and lists key contacts. Section 2.0 discusses informa-
tion relevant to the technology's application, including an
assessment of the technology related to the nine feasibility study
evaluation criteria, potential applicable environmental regula-
tions, and operability and limitations of the technology. Section
3.0 summarizes the costs associated with implementing the tech-
nology. Section 4.0 presents the waste characteristics,
demonstration approach, demonstration procedures, and the re-
sults and conclusions of the demonstration. Section 5.0
summarizes the technology status, and Section 6.0 includes a
list of references. The Appendix presents case studies provided
by the developer.
The remainder of this executive summary provides an over-
view of the Sonotech system; its waste applicability;
demonstration objectives, approach, and conclusions; other case
studies; and technology applicability.
The Sonotech System
Sonotech of Atlanta, GA, has developed a pulse combustion
burner technology that claims to offer benefits when applied in
a variety of combustion processes. The technology incorporates
a combustor that can be tuned to induce large-amplitude acous-
tic or sonic pulsations inside combustion process units, such as
boilers or incinerators.
A pulse combustor typically consists of an air inlet, a com-
bustor section, and a tailpipe. In the Cello® system, fuel oxidation
and heat release rates vary periodically with time, producing
periodic variations or pulsations in pressure, temperature, and
gas velocity. Sonotech claims that, when the entire unit is added
to an existing incinerator, the large-amplitude resonant pulsa-
tions of acoustic or sound waves excited by its tunable pulse
combustor can significantly improve an incinerator's perfor-
mance, thereby reducing capital investment and operating costs
for a wide variety of incineration systems.
To excite large-amplitude pulsations inside an incinerator, the
pulse combustor must operate at a frequency that equals one of
the natural, acoustic mode frequencies of the incinerator. When
this condition is satisfied, the pulsations inside the pulse com-
bustor and the incinerator are in resonance. Production of
large-amplitude pulsations is achieved by (1) retrofitting a tun-
able pulse combustor to a wall of the incinerator and (2) varying
its frequency until one of the natural acoustic modes of the in-
cinerator is excited. The desired resonant operating condition is
established by using one or more pressure transducers to moni-
tor changes in the amplitude of pulsations inside the incinerator
in response to changing the pulse combustor frequency. The de-
sired operating condition is reached when the transducers indicate
that the amplitude of pulsations inside the incinerator has been
maximized.
Pulse combustion can also be applied to a variety of other
combustion processes such as boilers, dryers, and calciners. In
such applications, the pulse combustor can be used as the com-
bustion process burner, supplying all of the heat input to the
process, or it can be used only to excite pulsations in the com-
bustion process. When used in such applications, the pulse
combustor delivers only a fraction of the combustion process
heat input (as little as 2%), while still exciting resonant pulsa-
tions in the process combustor. The remaining heat input is
supplied by the conventional burner.
Waste Applicability
The Sonotech Cello® system can be incorporated into the
construction of most new combustion devices or can be retrofit-
ted to many existing systems. The Cello® system can be used to
treat any material typically treated in a conventional incinerator.
For the SITE demonstration, the waste feed for all test runs
consisted of a mixture of contaminated soil, sludge, and tar from
two abandoned manufactured gas plant (MGP) Superfund sites.
One component of the waste feed consisted of a combination of
pulverized coal and contaminated coal-tar sludge from the
Peoples Natural Gas Company (Peoples) Superfund site in
Dubuque, IA. The other components of the waste feed material
ES-1
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were obtained from an MGP site in the southeastern U.S. and
consisted of contaminated soil borings and tar waste from an oil
gasification process.
Sonotcch believes their technology is ready to be used for the
full-scale incineration of contaminated solids, liquids, sludges,
and medical wastes.
Demonstration Objectives and Approach
The primary objective of the SITE program demonstration
was to develop test data to evaluate the treatment efficiency of
the Sonotech Cello® system compared to conventional com-
bustion. Test data were evaluated to determine if the Sonotech
system (1) increased incinerator capacity, (2) increased the de-
struction and removal efficiency (DRE) of principal organic
hazardous constituents (POHC), (3) decreased flue gas carbon
monoxide (CO) emissions, (4) decreased flue gas emissions of
nitrogen oxides (NOX), (5) decreased flue gas soot emissions,
(6) decreased combustion air requirements, and (7) decreased
auxiliary fuel requirements.
The demonstration's secondary objective was to develop ad-
ditional data to evaluate whether the Sonotech system, compared
to conventional combustion, (1) reduced the magnitude of tran-
sient puffs of CO and total unburned hydrocarbons (TUHC); (2)
resulted in reduced incineration costs; (3) significantly changed
the distribution of hazardous constituent trace metals among the
incineration system discharge streams (including kiln bottom ash,
scrubber liquor, and baghouse exit flue gas); and (4) increased
the leachability of the toxicity characteristic leaching procedure
(TCLP) trace metals from kiln ash.
The demonstration program objectives were achieved by col-
lecting solid, liquid, and gas phase samples, as well as Sonotech
and IRF pilot-scale rotary kiln incineration system (RKS) pro-
cess operating data. To meet the objectives, data were collected
for four different incineration system operating conditions, each
performed in triplicate, for a total of 12 individual tests. The
four test conditions included the following:
• Test Condition 1, conventional combustion at typical oper-
ating conditions
• Test Condition 2, conventional combustion at its maximum
fccdrate
• Test Condition 3, Sonotech pulse combustion at the maxi-
mum fcedrate for conventional combustion (the same
nominal fcedrate as Test Condition 2)
• Test Condition 4, Sonotech pulse combustion at its maxi-
mum fcedrate
Demonstration Conclusions
Data collected during the Sonotech SITE demonstration were
evaluated using the rank sum test The rank sum test allows the
user to assess whether observed differences in data sets are sta-
tistically significant. When comparing two data sets, each
containing three data points, the two data sets are different at the
95% confidence level when there is no data overlap. Unless noted,
all conclusions are based on comparison of the average results
from Test Condition 3 to the average results from Test Condi-
tion 2. The following conclusions may be drawn about the
benefits of the Sonotech system:
• The Sonotech system increased the incinerator waste
feedrate capacity by 13% compared to conventional com-
bustion when comparing Test Condition 4 to Test Condition
2. The capacity increase was equivalent to reducing the aux-
iliary fuel needed to treat a unit mass of waste from an
average of 21,100 British thermal units per pound of waste
(Btu/lb) (range of 21,000 to 21,300) for conventional com-
bustion to 18,000 Btu/lb (range of 16,600 to 19,000) for the
Sonotech system. Visual observations indicated improved
mixing in the incinerator cavity when the Sonotech system
was operating.
• Benzene DREs for all 12 test runs were greater than
99.994%. The Sonotech system reduced the average ben-
zene emission rate from 7.7 milligrams per hour (mg/hr)
(range of 2.1 to 12) to 5.7 mg/hr (range of 3.4 to 6.9) at the
afterburner exit.
• Naphthalene DREs were greater than or equal to 99.998%
for all test runs. The Sonotech system reduced the average
naphthalene emission rate from 1.2 mg/hr (range of less than
0.3 to 6.2) to 1.1 mg/hr (range of less than 0.3 to 2.5) at the
afterburner exit.
• The average afterburner CO emissions, corrected to 7%
oxygen (O2), decreased from 20 parts per million (ppm)
(range of 8.0 to 40.0) with conventional combustion to 14
ppm (range of 12.6 to 16.0) with the Sonotech system.
• The average afterburner NOx emissions, corrected to 7%
oxygen, decreased from 82 ppm (range of 78.3 to 85.1) with
conventional combustion to 77 ppm (range of 68.0 to 87.1)
with the Sonotech system.
• Average afterburner soot emissions, measured as total or-
ganic carbon (TOC) and corrected to 7% oxygen, were
reduced from 1.9 milligrams per dry standard cubic meter
(mg/dscm) (range of less than 0.9 to 2.7) for conventional
combustion to less than 1.0 mg/dscm (range of less than 0.8
to 0.9) with the Sonotech system.
• Total system combustion air requirements, determined from
stoichiometric calculations, were lower with the Sonotech
system in operation. The ranges for these values were 38,400
to 40,600 dry standard cubic feet per hour (dscf/hr) without
the Sonotech system and 34,800 to 39,900 dscf/hr with the
Sonotech system operating.
• Total natural gas fuel requirements (including kiln and after-
burner) for all test conditions were similar. The total system
average natural gas usage was 1,540 dscf/hr (range of 1,480
to 1,590) for conventional combustion and 1,580 dscf/hr (range
of 1,520 to 1,620) for the Sonotech system at approximately
the same feedrate.
ES-2
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No substantial increase or decrease occurred in the frequency
or magnitude of transient CO or TUHC puffs with the Sonotech
system operating.
Under the demonstration test conditions, use of the Sonotech
system with the reported increase in incineration capacity can
result in a cost savings. The reader is referred to the Econom-
ics section of this report to determine the approximate cost
savings for a specific application.
During the Sonotech demonstration, the Cello® combustion
system caused no downtime and was judged to be reliable.
Target metals investigated included antimony, barium,
beryllium, cadmium, chromium, lead, and mercury. Their
distribution in the discharge streams of the RKS did not
vary significantly from test to test or from test condition
to test condition except for barium and chromium. Con-
centrations of these two metals were slightly lower in
the scrubber liquor and measurably higher in the
baghouse exit flue gas when the Sonotech system was
operating.
• The concentrations of target metals in the TCLP leachates
were low to not detected in the feed, kiln ash, and scrub-
ber liquor. At these concentrations, no significant
test-to-test variations in the TCLP leachability of the
various discharge streams were observed.
1 No volatile or semivolatile organic compounds, other than
benzene, were detected in any kiln ash or scrubber liquor
samples.
1 Dioxin toxicity equivalent values for all runs were very
low and no clear distinctions were noticed with the
Sonotech system operating.
1 Stack particulate and hydrogen chloride emissions were
very low with no distinct variations between different
test conditions.
Other Case Studies
According to the developer, the Sonotech system has been
used, under test conditions, to evaluate the rate of spray
evaporation of water, calcination of limestone, and heating
of steel cylinders. Case studies, provided by Sonotech, in-
volving these studies and the developer's interpretation of
the data collected during this SITE demonstration, are in-
cluded as Appendix A to this report.
Technology Applicability
Data obtained on the Sonotech system were analyzed to
determine the advantages, disadvantages, and limitations of
the technology. The Sonotech system was evaluated based
on the nine criteria used for decision making in the Superfund
feasibility study process.
For a given application, the overall effectiveness of the
Sonotech system depends upon numerous factors including
characteristics of the waste, such as its heat content, and the
incinerator design, such as its waste feed system. The claimed
benefits of the technology may only be fully realized with
high heat-content, organic-contaminated soils.
The technology can be incorporated into almost any new
incineration system and can be used as a retrofit to most ex-
isting incinerators, boilers, and dryers.
Materials-handling requirements and SITE-support re-
quirements are minimal and are identical to those of the
existing incinerator.
The SITE program demonstration evaluated the
technology's ability to treat wastes contaminated with vola-
tile and semivolatile organic compounds. Accordingly, the
Sonotech system should be applicable to the incineration of
wastes contaminated with pesticides, polychlorinated biphe-
nyls (PCB), dioxins and furans.
ES-3
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Section 1.0
Introduction
This section provides background information about the EPA
SITE program, discusses the purpose of this ITER, and describes
the Cello® pulse burner system developed by Sonotech, of At-
lanta, GA. Additional information about the SITE program, the
Sonotech technology, and the demonstration can be obtained by
contacting the key individuals listed at the end of this section.
1.1 The SITE Program
The SITE program was established by the EPA Office of Solid
Waste and Emergency Response (OSWER) and Office of Re-
search and Development (ORD) in response to the Superfund
Amendments and Reauthorization Act of 1986 (SARA). The
SITE program's primary purpose is to promote the use of alter-
native technologies in cleaning up hazardous waste sites. The
various component programs under SITE are designed to en-
courage the development, demonstration, and use of new or
innovative treatment and monitoring technologies. The program
is designed to meet four primary objectives:
• Identify and remove obstacles to the development and com-
mercial use of alternate technologies.
• Structure a development program that nurtures emerging
technologies.
• Demonstrate promising innovative technologies to estab-
lish reliable performance and cost information for site
characterization and cleanup decision-making.
• Develop procedures and policies that encourage the selec-
tion of available alternative treatment remedies at S uperf und
sites, as well as other waste sites and commercial facilities.
Technologies are selected for the SITE Demonstration Pro-
gram through annual requests for proposals. ORD staff review
the proposals to determine which technologies show the most
promise for use at Superfund sites. Technologies chosen must
be at the pilot- or full-scale stage, must be innovative, and must
have some advantage over existing technologies. Mobile or trans-
portable technologies are of particular interest.
Once EPA has accepted a proposal, cooperative agreements
between EPA and the developer establish responsibilities for
conducting the demonstrations and evaluating the technology.
The developer is responsible for demonstrating the technology
at the selected site and is expected to pay any costs of transport-
ing, operating, and removing the equipment. EPA is responsible
for project planning, sampling and analysis, quality assurance
and quality control, preparing reports, disseminating informa-
tion, and transporting and disposing of treated waste materials.
The results of the demonstration are published in two basic
documents: the SITE Technology Capsule and the ITER. The
SITE Technology Capsule provides preliminary information on
the technology, emphasizing key results of the SITE demonstra-
tion. The ITER is discussed below. Both documents are intended
for use by remedial managers who need a detailed evaluation of
the technology for a specific site and waste.
1.2 Innovative Technology Evaluation
Report
The ITER provides information on the Sonotech technology
and includes a comprehensive description of the demonstration
and its results. The ITER is intended for use by EPA remedial
project managers, EPA on-scene coordinators, contractors, and
other decision makers for implementing specific remedial ac-
tions. The ITER is designed to aid decision makers in further
evaluating specific technologies for consideration as an appli-
cable option in a particular cleanup operation.
To encourage the general use of demonstrated technologies,
the ITER provides information regarding the applicability of each
technology to specific sites and wastes. In particular, the report
includes information on cost and site-specific characteristics. It
also discusses advantages, disadvantages, and limitations of the
technology.
Each SITE demonstration evaluates the performance of a tech-
nology in treating a specific material. Because the characteristics
of other materials may differ from the characteristics of the treated
material, successful field demonstration of a technology at one
site does not necessarily ensure that it will be applicable at other
sites. Data from the field demonstration may require extrapola-
tion for estimating the operating ranges in which the technology
will perform satisfactorily. Only limited conclusions can be drawn
from a single field demonstration.
1.3 Project Description
Sonotech of Atlanta, GA, has developed a frequency-tunable
pulse combustion burner technology that claims to offer ben-
efits when applied in a variety of combustion processes. The
burner system incorporates a pulse combustor that can be tuned
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to excite large-amplitude sonic pulsations inside a combustion
chamber, such as a boiler or incinerator. These pulsations in-
crease the rates of heat, mixing (momentum), and mass transfer
in the combustion process. Sonotech claims that these rate in-
creases in heat, mixing, and mass transfer are sufficient to result
in significantly faster and more complete combustion.
Sonotech has targeted waste incineration as a potential appli-
cation for this technology. In an earlier EPA demonstration of its
pulse combustion system, Sonotech retrofitted a pulse combus-
tion burner to the EPA bench-scale rotary kiln incinerator in
Research Triangle Park, NC. Tests were performed to measure
the effect of pulsations on incinerator emissions of soot, CO,
andTUHC.
Based on this initial experience, Sonotech proposed a
follow-up demonstration under the SITE program. Sonotech
proposed that its pulse combustion technology be evaluated on
a larger scale incineration system, specifically the pilot-scale RKS
at the EPA IRF in Jefferson, AR.
To evaluate the Sonotech technology at the IRF, tests were
performed in triplicate at four different incineration system op-
crating conditions, for a total of 12 individual tests. The four test
conditions included (1) conventional combustion at typical op-
crating conditions; (2) conventional combustion at its maximum
fccdratc; (3) Sonotech pulse combustion at the conventional
combustion maximum feedrate (the same nominal feedrate as
condition 2); and (4) Sonotech pulse combustion at its maxi-
mum feedrate.
1.4 Technology Description
A pulse combustor typically consists of an air inlet, a com-
bustor section, and a tailpipe. In pulse combustion, fuel oxidation
and heat release rates vary over time. These variations produce
periodic variations or pulsations in combustor section pressure,
temperature, and gas velocities. The frequency of pulsations is
generally close to the resonant frequency of the fundamental
longitudinal acoustic mode of the combustor section and tailpipe.
Titus, by changing combustor and tailpipe geometry—for ex-
ample, by varying the length of the tailpipe—the frequency of
pulsations can be changed, or tuned. Furthermore, if properly
applied, a pulse combustor can excite large-amplitude resonant
pulsations of 150 decibels (dB) or higher within a cavity down-
stream of thepulse combustor tailpipe. The combustion chamber
of a boiler or an incinerator is an example of this type of cavity.
Compared to nonpulsating combustion, the technology's pe-
riodic pulsations in pressure, gas velocity, and temperature can
increase the rates of mass, heat, and mixing transfer. Sonotech
claims that these pulsations improve combustion efficiency and
more completely oxidize or destroy organic compounds.
With the development of frequency-tunable pulse combustors
that can excite large-amplitude pulsations in combustion cham-
bers downstream of the pulse combustor, it becomes possible to
apply pulse combustion to a variety of combustors, such as boil-
ers, dryers, calciners, and incinerators. In such applications, the
pulse combustor can be used as the main combustion burner,
supplying all of the heat input to the process. Alternatively, the
pulse combustor can be used only as the driver to excite pulsa-
tions in the combustion process. In such applications the pulse
combustor would deliver only a fraction, as little as 2%, of the
combustion heat input, while still exciting resonant pulsations
in the combustor. The remaining heat input would be supplied
by normal means, such as by the conventional burner.
To excite large-amplitude pulsations inside an incinerator, for
example, the pulse combustor must operate at a frequency that
equals one of the natural acoustic modes of the incinerator. When
this condition is satisfied, the pulsations inside the pulse com-
bustor and the incinerator are in resonance. Resonant driving of
large-amplitude pulsations is achieved by retrofitting a tunable
pulse combustor to a wall of the incinerator and varying its fre-
quency until one of the natural acoustic modes of the incinerator
is excited. The desired resonant operating condition is estab-
lished in practice by using one or more pressure transducers to
monitor changes in the amplitude of pulsations inside the incin-
erator in response to changes in the pulse combustor frequency.
The desired operating condition is reached when these trans-
ducers indicate that the amplitude of pulsations inside the
incinerator has been maximized.
The SITE demonstration of the Sonotech technology involved
retrofitting the kiln section of the RKS at the IRF with a S onotech
pulse combustor to deliver a design heat input of 73 kilowatts
(kW) (250,000 British thermal units per hour [Btu/hr]), or roughly
15% to 20% of the typical heat input to the kiln of the RKS.
Sonotech claims that this application of the pulse combustion
technology has the following advantages over conventional,
nonpulsating incineration:
1. Higher incinerator capacity
2. Lower CO, soot, and NOx emissions
3. Lower combustion air requirements
4. Lower energy requirements
5. Reduced severity of transient puffs
6. Reduced incineration system capital and operat-
ing costs
1.5 Key Contacts
Additional information on the Sonotech technology and the
SITE program can be obtained from the following sources:
The Sonotech Technology
Dr. Ben T. Zinn
President
Sonotech, Inc.
3656 Paces Ferry Road
Atlanta, GA 30327
404-894-3033
FAX: 404-894-2760
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The SITE Program
Robert A. Olexsey
Director, Land Remediation and Pollution Control Division
National Risk Management Research Laboratory
U.S. Environmental Protection Agency
26 West Martin Luther King Drive
Cincinnati, OH 45268
513-569-7861
FAX: 513-569-7620
Marta K. Richards
EPA SITE Project Manager
National Risk Management Research Laboratory
U.S. Environmental Protection Agency
26 West Martin Luther King Drive
Cincinnati, OH 45268
513-569-7692
FAX: 513-569-7676
Information on the SITE program is available through the
following on-line information clearinghouses:
• The Alternative Treatment Technology Information Center
(ATTIC) System is a comprehensive, automated, informa-
tion retrieval system that integrates data on hazardous waste
treatment technologies into a centralized source. The sys-
tem operator can be reached at 301-670-6294.
• The Vendor Information System for Innovative Treatment
Technologies (VIS ITT) database contains information on
154 technologies offered by 97 developers. The hotline num-
ber is 800-245-4505.
• The OSWER CLU-In electronic bulletin board contains in-
formation on the status of SITE technology demonstrations.
The system operator can be reached at 301-585-8368.
Technical reports may be obtained by contacting the EPA Cen-
ter for Environmental Research Information (CERI) at 26 West
Martin Luther King Drive, Cincinnati, OH 45268; telephone
513-569-7562.
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Section 2.0
Technology Applications Analysis
This section assesses the general applicability of the S onotech
Cello® pulse combustion system to remediate waste and con-
taminated soils from Superfund sites. This assessment is based
on results from the demonstration of the technology under the
EPA SITE Program.
The waste feed for all tests consisted of a mixture of contami-
nated materials from two abandoned MGP Superfund sites. One
component of the test feed material was a combination of pul-
verized coal and contaminated coal-tar sludge from the Peoples
Superfund site in Dubuque, IA. Other components of the test
feed material included contaminated soil borings and a tar waste
from an oil gasification process at an MGP site in the southeast-
cm U.S.
2.1 Feasibility Study Evaluation Criteria
Tin's subsection assesses the Sonotech technology relative to
the nine evaluation criteria used to conduct detailed analyses of
remedial alternatives in feasibility studies performed under the
Comprehensive Environmental Response, Compensation, and
Liability Act (CERCLA). Table 1 summarizes the evaluation
criteria as they relate to the performance of the technology.
2.1.1 Overall Protection of Human Health
and the Environment
This criterion addresses whether or not a remedy provides
adequate protection and describes how risks posed by each path-
way arc eliminated, reduced, or controlled through treatment,
engineering controls, or institutional controls.
The Sonotech technology provides both short- and long-term
protection to human health and the environment by thermally
destroying hazardous organic compounds contained in the wastes.
Exposure from air emissions is minimized by removing con-
taminants in flue gas using an APCS. Potential accidental releases
could temporarily affect air quality in the vicinity of the site.
Short-term exposure to workers may occur when preparing the
kiln ash and scrubber liquor for off-site disposal.
For the test program, the primary APCS consisted of a venturi
scrubber followed by a packed-column scrubber and fabric-fil-
ter baghouse. The scrubber system was operated at as close to
total rccirculation (or zero blowdown) as possible. To assure
permit compliance, a secondary, or redundant, APCS consisted
of a demister, an activated-carbon adsorber and a high-efficiency
particulate air (HEPA) filter.
2.1.2 Compliance with ARARs
This criterion addresses whether or not a remedy will meet all
of the ARARs of other federal and state environmental statutes.
General and specific ARARs identified for the Sonotech tech-
nology are presented in Section 2.2. Compliance with chemical-,
location-, and action-specific ARARs should be determined on
a site-specific basis; however, location-, and action-specific
ARARs generally can be met. Compliance with chemical-specific
ARARs depends on the chemical constituents of the waste and
the treatment efficiency of the combustion system. A trial burn
may be required to determine specific operating conditions.
2.1.3 Long-Term Effectiveness and
Permanence
This criterion refers to the ability of a remedy to maintain
reliable protection of human health and the environment over
time.
Thermal destruction is a proven treatment technology for haz-
ardous wastes containing organic compounds. The Sonotech
system can be incorporated into the construction of most new
combustion devices or can be retrofit to many existing systems
to treat any material typically treated in a conventional incinera-
tor. The Sonotech system was found to have a very small, but
observable benefit, to the IRF RKS DRE of the POHC. POHC
DREs measured for all test conditions were uniformly 99.994%
or greater. Treatment residuals require proper off-site treatment
and disposal.
2.1.4 Reduction of Toxicity, Mobility, or
Volume through Treatment
This criterion refers to the anticipated performance of the treat-
ment technology potentially used in a Superfund remediation.
With incineration, the toxicity and volume of the waste feed is
reduced through thermal destruction of hazardous organic com-
ponents.
Sonotech test data demonstrated that organic components in
the hazardous waste feed can be destroyed with at least 99.994%
or greater DRE. The data also suggest that incineration residue
quality, as measured by residue (kiln ash) heating value, was
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Table 1. Feasibility Study Evaluation Criteria for the Sonotech Technology
Criterion
Sonotech Technology Performance
Overall Protection of Human
Health and the Environment
Compliance with Federal ARARs
Long-Term Effectiveness and Permanence
Reduction of Toxicity, Mobility, or
Volume Through Treatment
Short-Term Effectiveness
Implementability
Cost
State Acceptance
Community Acceptance
The Sonotech technology used with a conventional combustion chamber destroys organic
hazardous constituents in the waste feed. Air emissions are reduced by using an air pollution
control system (APCS).
Compliance with chemical-, location-, and action-specific applicable or relevant and appropriate
requirements (ARARs) must be determined on a site-specific basis. Compliance with
chemical-specific ARARs depends on the treatment efficiency of the combustion system and the
chemical constituents of the waste.
Contaminants are permanently removed from the waste. Treatment residuals from the APCS
and the kiln ash require proper off-site treatment and disposal.
With incineration, both the toxicity and volume of the waste are reduced by destroying organic
components of the waste. Metals in the gas phase emissions and the kiln ash are unaffected.
The Sonotech system effectively reduces the time required for treatment by increasing the
feedrate of a conventional combustion system. Short-term risks to workers, the community, and
the environment arepresented during waste handling activities and from potential exposures to
flue gas emissions and noise. Adverse impacts from both can be mitigated with proper controls
and procedures.
The Sonotech system can be easily incorporated into new incinerators and can be retrofit to
most existing incinerators. In addition, the system can be used to treat any material treated in a
conventional incinerator.
Under the demonstration test conditions.the Sonotech system can produce cost savings due to
increased incinerator capacity. The reader is referred to Section 3.0 of this report, Economic
Analysis, to determine the approximate cost saving for a particular application.
State acceptance is anticipated to be favorable because the system can be retrofit to an existing
permitted hazardous waste incinerator to improve the performance of conventional combustion
technology.
The minimal short-term risks presented to the community along with the permanent removal of
hazardous waste constituents and the improved performance of a permitted waste combustion
unit should increase the likelihood of community acceptance of this technology.
improved with pulse combustion. The technology had no effect
on the TCLP teachability of metals in kiln ash. Gas phase emis-
sions were controlled by a primary and secondary APCS. Any
treatment residual (such as kiln ash, scrubber liquor, orbaghouse
ash) possessing a hazardous waste characteristic must be shipped
off site to a permitted treatment, storage, and disposal facility.
No residuals from this demonstration possessed hazardous waste
characteristics.
Sonotech demonstration test data showed that the concentra-
tions of the target metals (antimony, barium, beryllium, cadmium,
chromium, lead, and mercury) in the TCLP leachates were low
or not detected in the feed, kiln ash, and scrubber liquor samples.
At these concentrations, no significant variations in the TCLP
teachability of the two waste streams were observed. Insuffi-
cient baghouse flyash was collected to allow for metals analysis
of that waste.
2.1.5 Short-Term Effectiveness
This criterion addresses the period of time needed to achieve
protection of human health and the environment and any ad-
verse impacts that may be posed during the construction and
implementation period until cleanup goals are achieved.
The Sonotech system can easily be incorporated into new in-
cinerators or incineration systems and can be retrofit to most
existing combustion systems. Installation of the Sonotech sys-
tem to the IRF RKS and shakedown testing required about 2
weeks. Other than the noise produced by the system, no adverse
impacts to the community, workers, or the environment would
be anticipated as a result of the installation of the Sonotech sys-
tem.
During the SITE demonstration, the capacity of the RKS in-
cinerator (as judged by increased feedrate to the kiln) showed a
13% to 35% increase with the use of the Sonotech system over
conventional combustion. The time requirement for treatment is
effectively reduced by increasing the feedrate over a conven-
tional combustion system.
Because the Sonotech system relies on the resonant frequency
of the incinerator to excite large-amplitude pulsations, incorrect
application of the sound energy generated by the pulse combus-
tion may present structural problems in older incineration
systems. Other noise problems caused by the system can be miti-
gated by enclosing the system with sound insulation and
monitoring worker exposures to excessive noise levels. Other
potential short-term risks presented during system operation to
workers, the community, and the environment may include ex-
posures to hazardous substances during waste handling activities
and exposures to flue gas emissions. Adverse impacts during
waste handling activities are minimized by following proper
waste handling procedures and by using proper personal protec-
tion equipment (PPE). Adverse impacts from the flue gas
emissions are mitigated by passing the emissions through an
APCS.
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2.1.6 Implementability
This criterion considers the technical and administrative fea-
sibility of a remedy, including the availability of materials and
services needed to implement a particular option.
The Sonotech system can be easily incorporated into new in-
cinerators and can be retrofit to most existing incinerators. In
addition, the system can be used to treat any material typically
treated in a conventional incinerator with very few limitations.
Site requirements for an incinerator equipped with the
Sonotech system would be nearly identical to those of an incin-
erator without the system. The Sonotech pulse combustor requires
about 4 feet by 10 feet of additional area on one side of the in-
cinerator where the system can be mounted. A port into the
incinerator's primary combustion chamber is needed to insert
the internal portion of the Sonotech burner. The system requires
attachment of ah- and natural gas lines, and it requires only a
nominal amount of additional electricity. Depending on the ap-
plication and location, sound control may be necessary.
2.1.7 Costs
This criterion should address estimated capital and operation
and maintenance costs as well as net present worth costs.
Under the demonstration test conditions, use of the Sonotech
system can result in a cost savings due to increased incinerator
capacity. The reader is referred to Section 3.0 of this report to
determine the approximate cost savings for a particular applica-
tion.
2.1.8 State Acceptance
This criterion addresses the technical or administrative issues
and concerns the support agency may have regarding the tech-
nology.
State acceptance is anticipated to be favorable because the
Sonotech system can be used as a retrofit to an existing permit-
ted hazardous waste incinerator to improve the performance of
the combustion technology. In cases where the installation of
the pulse combustion technology increases the unit's feedrate,
the Sonotech retrofit combustion unit would require a RCRA
permitmodification.The definition and requirements for a RCRA
permit modification are provided in 40 Code of Federal Regula-
tions (CFR) Part 270.42. The definition and requirements for a
Clean Air Act (CAA) New Source Performance Standards
(NSPS) modification are provided in 40 CFR Part 60.14. Gen-
erally, both modification processes require review by the
permitting agency before retrofit. In addition, modification re-
quirements may include public notification and retesting of the
unit.
The Sonotech SITE demonstration was conducted under the
restrictions of the IRF hazardous waste management permit,
administered by the Arkansas Department of Pollution Control
and Ecology. Test data indicate that the pulse combustion tech-
nology increased the waste feedrate without resulting increases
in flue gas soot, CO, or NOX emissions.
2.1.9 Community Acceptance
This criterion addresses any issues or concerns the public may
have regarding the technology.
Public acceptance of this technology should be positive for
three reasons: (1) the technology presents minimal short-term
risks to the community, (2) it permanently removes hazardous
constituents from the waste, and (3) it improves the performance
of a permitted waste combustion unit.
2.2 Technology Performance Regarding
ARARs
This section discusses potential environmental regulations
pertinent to the demonstration and operation of the Sonotech
pulse combustion system, including the transport and treatment,
storage, and disposal (TSD) of wastes and treatment residuals.
CERCLA, as amended by SARA, requires consideration of
ARARs. CERCLA issues, although not true ARARs, are also
considered.
Regulations that apply to a particular remediation activity
depend on the type of remediation site and the type of waste
treated. State and local regulatory requirements, which may be
more stringent, must also be addressed by remedial managers.
ARARs for the Sonotech demonstration or potential use of the
Sonotech technology include the following: (1) RCRA, (2) CAA,
(3) Toxic Substances Control Act (TSCA), and (4) Occupational
Safety and Health Administration (OSHA) regulations. Table 2
summarizes these regulations, which are discussed in greater
detail below.
2.2.1 Comprehensive Environmental
Response, Compensation, and
Liability Act
CERCLA, as amended by SARA, provides for federal author-
ity to respond to releases or potential releases of any hazardous
substance into the environment, as well as to releases of pollut-
ants or contaminants that may present an imminent or significant
danger to public health and welfare or the environment. Reme-
dial alternatives that significantly reduce the volume, toxicity,
or mobility of hazardous materials and provide long-term pro-
tection are preferred. Selected remedies must also be
cost-effective and protective of human health and the environ-
ment.
Sonotech demonstration test data showed that the concentra-
tions of the target metals (antimony, barium, beryllium, cadmium,
chromium, lead, and mercury) in the TCLP leachates were low
or not detected in the feed, kiln ash, and scrubber liquor samples.
At these concentrations, no significant variations in the TCLP
leachability of the two waste streams were observed.
The Sonotech system has demonstrated that it can destroy
hazardous organic constituents in the feed stream with at least
99.99 DRE in the IRF RKS. Emissions of flue gases were con-
trolled with primary and secondary APCSs.
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Table 2. Potential Federal ARARs for the Sonotech Pulse Combustion System
Process Activity ARAR Description
Basis
Requirements
Waste feed RCRA 40 CFR Part 267 or state
characterization equivalent
TSCA 40 CFR Part 761 or state
equivalent
Transportation for RCRA 40 CFR Part 262 or state
off-site treatment equivalent
Storage prior to
processing
RCRA 40 CFR Part 261 or state
equivalent
RCRA 40 CFR Part 264 or state
equivalent
Storage after
processing
On- or off-site
disposal
Identify and characterize the waste
to be treated
If appropriate, apply standards to the
treatment and disposal of wastes con-
taining PCB
Mandate manifest requirement,
packaging, and labeling prior to trans-
porting
Set transportation standards
Apply standards for the storage of
hazardous waste
Waste processing -
incineration
RCRA 40 CFR Parts 264, 265, 266
(Boilers and Industrial Furnaces [BIF]
Rule in Subpart H), and 270
TSCA 40 CFR Part 761.70
RCRA 40 CFR Part 264 or state
equivalent
RCRA 40 CFR Part 264 or state
equivalent
A RCRA requirement must be met
before managing and handling the
waste.
During waste characterization, PCBs
may be identified in the waste feed
and would then be subject to TSCA
regulations
The waste may need to be manifested
and managed as hazardous waste.
The waste may need permits for
transportation as a hazardous waste.
Prior to treatment, the hazardous
waste may require on-site storage in
a waste pile, tank, or container.
Apply standards for the incineration of
hazardous waste at permitted and interim
status facilities
Apply performance standards for the
incineration of liquid and nonliquid PCB
waste
Apply standards for the storage of hazard-
ous waste: requirements for storage of
hazardous waste in tanks and containers
will apply
Apply standards for landfilling hazardous
waste
Incineration of hazardous waste must
be conducted in a manner that meets
the RCRA operating and monitoring
requirements.
Incineration of PCB wastes must be
conducted in a manner that meets the
TSCA operating and monitoring
requirements.
If treatment residue is derived from the
treatment of a RCRA hazardous
waste, requirements for storage of
hazardous waste in tanks and
containers will apply.
Treatment residue may need to be
managed as a hazardous waste if it is
derived from treatment of hazardous
waste.
Chemical and physical analyses must be
performed.
Chemical and physical analyses must be
performed. If PCBs are identified, the waste
feed will be managed according to TSCA
regulations.
An identification number must be obtained
from EPA.
A transporter licensed by EPA must be used
to transport the hazardous waste.
The material should be placed in a waste
pile on plastic and covered with additional
plastic that is secured to minimize fugitive
air emissions and volatilization. Tanks or
containers must be well maintained; the con-
tainer storage area, if used, must be con-
structed to control runon and runoff. The time
between storage and treatment should be
minimized.
Equipment must be operated and maintained
daily. Air emissions must be characterized by
continuous emissions monitoring (CEM).
Equipment must be decontaminated when
operations are complete.
Rate and quantity of feed stream must be
measured and recorded at regular intervals;
temperature of incinerator shall be continu-
ously measured and recorded; temperature-
specific residence time requirements must be
met.
The treatment residue must be stored in
tanks or containers that are well maintained;
container storage area, if used, must be con-
structed to control runon and runoff.
Wastes must be disposed of at a RCRA-
permitted hazardous waste facility, or
approval must be obtained from EPA to dis-
pose of wastes on site. (continued)
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Table 2. Continued
Process Activity
ARAR
Description
Basis
Requirements
oo
RCRA 40 CFR Part 268 or state
equivalent
Transportation for RCRA 40 CFR Part 262 or state
off-site processing equivalent
RCRA 40 CFR Part 263 or state
equivalent
Flue Gas Emissions CAA or equivalent State Implemen-
tation Plan
Worker Safety OSHA 29 CFR Parts 1900 through
1926; or state OSHA requirements
Apply standards that restrict the placement The hazardous waste may be subject
of certain hazardous wastes in or on the to federal land disposal restrictions
ground (LOR).
Apply manifest requirements and packag-
ing and labeling requirements prior to
transporting
Apply transportation standards
Control air emissions that may impact
attainment of ambient air quality stand-
ards
Apply worker health and safety
standards
The treatment residue may need to be
manifested and managed as a haz-
ardous waste if it is derived from treat-
ment of hazardous waste.
Spent carbon may need to be trans-
ported as a hazardous waste if it is
derived from treatment of hazardous
waste.
The Sonotech technology system can
incorporate a primary and secondary
APCS to treat flue gas emissions.
Treated air is emitted to the atmo-
sphere.
CERCLA Remedial actions and RCRA
corrective actions must follow require-
ments for the health and safety of
on-site workers.
Wastes must be characterized to determine
if LDRs apply; treated wastes must be tested
and results compared to standard
An identification number must be obtained
from EPA
A transporter licensed by EPA must be used
to transport the hazardous waste according
to EPA regulations.
Treatment of contaminated air must ade-
quately remove contaminants so that air
quality is not impacted.
Workers must have completed and
maintained OSHA training and medi-
cal monitoring; use of appropriate
personal protective equipment (PPE)
is required.
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Incineration of hazardous waste generally takes place off site
at a RCRA-permitted TSD facility, although portable incinera-
tors can be used for on-site treatment. The Sonotech system can
be applied to either of these applications. Disposal of residual
wastes generated during on-site application mightrequire off-site
disposal or treatment. All on-site actions must meet all substan-
tive state and federal ARARs. Substantive requirements pertain
directly to actions or conditions in the environment (e.g., air
emission standards). Off-site actions must comply with legally
applicable substantive and administrative requirements; admin-
istrative requirements, such as permitting, facilitate the
implementation of substantive requirements.
On-site remedial actions must comply with all federal ARARs
as well as more stringent state ARARs. ARARs are determined
on a site-by-site basis and may be waived under six conditions:
(1) the action is an interim measure, and the ARAR will be met
at completion; (2) compliance with the ARAR would pose a
greater risk to health and the environment than noncompliance;
(3) it is technically impracticable to meet the ARAR; (4) the
standard of performance of an ARAR can be met by an equiva-
lent method; (5) a state ARAR has not been consistently applied
elsewhere; and (6) fund balancing, where ARAR compliance
would entail such cost in relation to the added degree of protec-
tion or reduction of risk afforded by that ARAR that remedial
action at other sites would be jeopardized. These waiver options
apply only to Superfund actions taken on site, and justification
for the waiver must be clearly demonstrated. Off-site
remediations are not eligible for ARAR waivers, and all sub-
stantive and administrative applicable requirements must be met.
2.2.2 Resource Conservation and
Recovery Act
RCRA, as amended by the Hazardous and Solid Waste Dis-
posal Amendments of 1984, regulates the management and
disposal of municipal and industrial solid wastes. The EPA and
RCRA-authorized states [listed in 40 CFR Part 272] implement
and enforce RCRA and state regulations.
A retrofit application of the Sonotech pulse combustion sys-
tem with a rotary kiln incinerator was evaluated by using a
hazardous waste feed mixture of sludge, soil, tar, and coal. The
Sonotech system may also be used with other combustion pro-
cess units, such as BIF, to treat a variety of waste types. The
pertinent RCRA regulations would need to be determined for
each specific application.
The presence of RCRA-defined hazardous waste determines
whether RCRAregulations apply to the Sonotech technology. If
hazardous wastes are treated or generated during the operation
of the technology, all RCRA requirements regarding the man-
agement and disposal of hazardous wastes must be addressed.
RCRA regulations define hazardous wastes and regulate their
transport and TSD. Wastes defined as hazardous under RCRA
include characteristic and listed wastes. Criteria for identifying
characteristic hazardous wastes are included in 40 CFR Part 261
Subpart C. Listed wastes from nonspecific and specific indus-
trial sources, off-specification products, spill cleanups, and other
industrial sources are itemized in 40 CFR Part 261 Subpart D.
If hazardous wastes are treated by the Sonotech system, the
owner or operator of the treatment or disposal facility must ob-
tain an EPA identification number and a RCRA permit from EPA
or the RCRA-authorized state. RCRA requirements for permits
are specified in 40 CFR Part 270.
As mentioned in Section 2.1.8, in cases where the Sonotech
system is retrofit to a permitted combustion unit and it increases
the unit's overall feedrate, the modified unit will need to obtain
a RCRA permit modification. The definition and requirements
for a permit modification are provided in 40 CFR Part 270.42.
Generally, the process requires a review by the permitting agency
before beginning retrofit. In addition, modification requirements
may include public notification and retesting of the unit.
In addition to the permitting requirements, owners and opera-
tors of incinerators that treat hazardous waste must comply with
40 CFR Part 264 Subpart O. If the Sonotech system is used to
burn or process wastes in a BIF (as defined in 40 CFR Part
260.10), the BIF rule outlined in 40 CFR Part 266 Subpart H
becomes an ARAR.
Treatment residuals generated during the operation of the sys-
tem, including kiln ash, spent granular activated carbon, baghouse
ash, and scrubber liquor, must be stored and disposed of prop-
erly. If the treatment waste feed is a listed waste, treatment
residues must be considered listed wastes (unless RCRA delisting
requirements are met). If the treatment residues are not listed
wastes, they should be tested to determine if they are RCRA
characteristic hazardous wastes. If the residuals are not hazard-
ous and do not contain free liquids, they can be disposed of on
site or at a nonhazardous waste landfill. If the treatment residues
are hazardous, the following RCRA standards apply:
• Standards and requirements for generators of hazardous
waste, including hazardous treatment residues, are outlined
in 40 CFR Part 262. These requirements include obtaining
an EPA identification number, meeting waste accumulation
standards, labeling wastes, and keeping appropriate records.
Part 262 allows generators to store wastes up to 90 days
without a permit and without having interim status as a TSD
facility. If treatment residues are stored on site for 90 days
or more, 40 CFR Part 265 requirements apply.
• Any on- or off-site facility designated for permanent dis-
posal of hazardous treatment residues must be in compliance
with RCRA. Disposal facilities must fulfill permitting, stor-
age, maintenance, and closure requirements provided in 40
CFR Parts 264 through 270. In addition, any authorized state
RCRA requirements must be fulfilled. If treatment residues
are disposed of off-site, 40 CFR Part 263 transportation stan-
dards apply.
The waste feed mixture used during the Sonotech demonstra-
tion included contaminated soil borings from an MGP Superfund
site. Soils classified as hazardous waste are subject to land dis-
posal restrictions (LDR) under both RCRA and CERCLA.
Applicable RCRA requirements may include (1) a Uniform Haz-
ardous Waste Manifest if the treated soils are transported, (2)
restrictions on placing soils in land disposal units, (3) time lim-
-------
its on accumulating treated soils, and (4) permits for storing
treated soils.
Requirements for corrective action at RCRA-regulated facili-
ties are provided in 40 CFR Part 264, Subpart F (promulgated)
and Subpart S (proposed). These subparts also apply to reme-
diation at Superfund sites. SubpartsFand S includerequirements
for initiating and conducting RCRA corrective actions,
remediating groundwater, and ensuring that corrective actions
comply with other environmental regulations. Subpart S also
details conditions under which particular RCRA requirements
may be waived for temporary treatment units operating at cor-
rective action sites. Thus, RCRA mandates requirements similar
to CERCLA, and as proposed, may allow treatment units such
as the Sonotcch treatment system to operate without full per-
mits.
2.2.3 Clean Air Act
The CAA and its 1990 amendments establish primary and sec-
ondary ambient air quality standards for protection of public
health and emission limitations on certain hazardous air pollut-
ants.
CAA permitting requirements are administered by each state
as part of State Implementation Plans developed to bring each
state into compliance with National Ambient Air Quality Stan-
dards (NAAQS). Ambient air quality standards for specific
pollutants apply to the operation of the Sonotech system, be-
cause the technology ultimately results in an emission from a
point source to the ambient air. Allowable emission limits for
tltc operation of a Sonotech system will be established on a case-
by-casc basis depending upon the type of waste treated and
whether or not the site is in an attainment area of the NAAQS.
Allowable emission limits may be set for specific hazardous air
pollutants, paniculate matter, hydrogen chloride, or other pol-
lutants. If the site is in an attainment area, the allowable emission
limits may still be curtailed by the increments available under
Prevention of Significant Deterioration (PSD) regulations. Typi-
cally, an APCS similar to the type used during the SITE
demonstration will be required to control the discharge of flue
gas emissions to the ambient air.
ARARs pertaining to the CAA must be determined on a site-
by-sile basis. Remedial activities involving the Sonotech
technology may be subject to the requirements of Title I of the
CAA for the PSD of air quality in attainment (or unclassified)
areas. The PSD requirements will apply when remedial activi-
ties involve a major source or modification as defined in 40 CFR
Section 52.21; remedial activities subject to review must apply
the best available control technologies and demonstrate that the
activity will not adversely impact ambient air quality.
2.2.4 Toxic Substances Control Act
The disposal of PCB is regulated under Section 6(e) of TSCA.
PCB treatment and disposal regulations are described in 40 CFR
Part 761. Materials containing PCBs in concentrations between
50 and 500 ppm may either be sent to TSCA-permitted landfills
or destroyed by incineration at a TSCA-approved incinerator.
At concentrations greater than 500 ppm, the material must be
incinerated. Sites where PCB spills have occurred after
May 4,1987, must be addressed under the PCB Spill Cleanup
Policy outlined in 40 CFR Part 761, Subpart G. The policy ap-
plies to spills of materials containing 50 ppm or greater of PCBs
and establishes cleanup protocols for addressing such releases,
based on the volume and concentration of spilled material.
Application of the Sonotech system to an incinerator may be
an effective thermal destruction system for treating solid and
liquid wastes containing PCBs. If the system is used to treat
PCB-contaminated material, the remediation will require TSCA
authorization that defines operational, throughput, and disposal
constraints. If the PCB-contaminated material contains RCRA
wastes, RCRA compliance is also required.
2.2.5 Occupational Safety and Health
Administration Requirements
CERCLA remedial actions and RCRA corrective actions must
be performed in accordance with OSHA requirements detailed
in 20 CFR Parts 1900 through 1926, especially Part 1910.120,
which provides for the health and safety of workers at hazard-
ous waste sites. On-site construction activities, such as assembly
of a transportable incinerator, at S uperfund or RCRA corrective
actions sites must be performed in accordance with Part 1926 of
OSHA, which provides safety and health regulations for con-
struction sites. State OSHA requirements, which may be
significantly stricter than federal standards, must also be met.
All technicians operating the Sonotech treatment system are
required to have completed an OSHA training course and must
be familiar with all OSHA requirements relevant to hazardous
waste sites. For most sites, minimum PPE for technicians will
include gloves, hard hats, steel-toe boots, and coveralls. Depend-
ing on contaminant types and concentrations, additional PPE
may be required.
The Sonotech system produces a considerable volume of noise.
This noise can be controlled to a degree by sound insulation,
placement of the pulse combustor, or other means. Noise levels
will need to be monitored to ensure that workers are not ex-
posed to noise levels above a time-weighted average of 85 dBs
over an 8-hour day.
2.2.6 Technology Performance Regarding
ARARs During the Demonstration
In general, operation of the Sonotech Cello® combustor ret-
rofit to the IRF RKS met all applicable requirements of the
ARARs listed in Table 2. The specifics of the technology per-
formance versus the ARARs are discussed below.
Waste characterization and feed preparation requirements
would be the same for both conventional incineration (without
the pulse combustor retrofit), and with the Sonotech pulse com-
bustor retrofit. Typically, solid waste incineration in a rotary kiln
incinerator results in two residual discharge streams - solid kiln
bottom ash and scrubber liquor. When these waste streams are
derived from hazardous waste, they are treated as hazardous
waste as in the case of this test program. Analysis of the scrub-
ber liquor and kiln ash samples showed that, with respect to
disposal, there was no difference in the quality of the product
10
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streams (scrubber liquor and kiln ash) between conventional in-
cineration and the Sonotech system retrofit incineration.
Therefore, application of Sonotech technology did not result in
special requirements for the disposal of these waste streams.
Test results showed that flue gas emission performance speci-
fications were met for both conventional incineration and
Sonotech pulse combustion incineration. No special air pollu-
tion control device (APCD) was required, nor was there a need
to operate any APCD at conditions different from conventional
operation with the Sonotech system. The following are a sum-
mary of routine (permit-based) operating standards and
performance specifications compliance requirements that were
met, both under conventional incinerator operation and with the
Sonotech system retrofit.
• Target POHCs (benzene and naphthalene) DREs were
greater than 99.99% for all tests, as required by the hazard-
ous waste incinerator performance standards, which would
be ARARs for incineration treatment.
• Stack CO emissions were well below the permitted 100-ppm,
1-hour rolling average for all tests; this has become a per-
mit requirement for permitted hazardous waste incinerators.
• Stack paniculate loadings for all tests, at about 1 mg/dscm
(0.0004 grains per dry standard cubic foot [grain/dscf]), were
well below the maximum permissible level of 180 mg/dscm
(0.08 grain/dscf) required by the hazardous waste incinera-
tor performance standards, and even below the 1993 EPA
guidance level for waste combustors of 34 mg/dscm (0.015
grain/dscf).
• Hydrogen chloride emissions for all tests were below 0.2
grams per hour (g/hr) (0.0004 pound per hour [lb/hr]), and
well below the maximum permissible level of 1.8 kilograms
per hour (kg/hr) (4 lb/hr) required by the hazardous waste
incinerator performance standards.
• Dioxin and furan (PCDD and PCDF) emissions were at
0.1 nanograms per dry standard cubic meter (ng/dscm) or
less, corrected to 7% oxygen. This is well below the 1993
EPA guidance of 30 ng/dscm corrected to 7% oxygen. On a
2,3,7,8-TCDD toxicity equivalents basis, the emissions were
in the range of 0.0003 to 0.005 ng/dscm, corrected to 7%
oxygen. This is considerably less than the recently proposed
EPA standard of 0.2 ng/dscm, corrected to 7% oxygen.
In summary, operation of the Sonotech system during the dem-
onstration test program was in compliance with the RCR A-based
ARARs that would apply to an incineration process at a
Superfund site.
One potential issue affecting worker health and safety was
the noise-level of about 100 dB that was generated within the
vicinity of the Sonotech pulse combustor during its operation.
OSHA guidelines limit an individual's daily maximum expo-
sure to noise-levels of no greater than 85 dB on an 8-hour average
basis. During this test program IRF personnel were required to
wear suitable hearing protection devices when working near the
Sonotech system.
2.3 Operability of the Technology
The Sonotech Cello® pulse combustor was attached to the
primary combustion chamber of the RKS, as shown in Figure 1.
A previously existing hatch was removed and a flanged plate
was fabricated to attach the pulse combustor to the kiln. Natural
gas and air lines were drawn from the existing gas and air trains
for the IRF RKS. The efforts involved in configuring the
Sonotech pulse combustor into the RKS were moderate. After
an initial training totaling about 3-4 hours, the IRF operations
crew were able to easily operate the Sonotech burner. Startup
and operation of the Sonotech burner required manually turning
on the gas and air valves, setting them to the desired flowrates,
turning on the pulse combustion burner, allowing the burner to
heat up for 10-15 minutes after ignition, connecting the burner
to the kiln chamber, and then adjusting the pulsation frequency
to achieve resonance. This entire sequence of events took about
20-30 minutes. The Sonotech burner operating conditions and
system maintenance requirements are further discussed in Sec-
tions 4.3.1.1 and 4.3.1.2.
2.4 Applicable Wastes
The Sonotech combustor can be incorporated into the con-
struction of most new combustion devices or can be retrofit to
many existing systems. The burner system can be used to treat
any material typically treated in a conventional combustion de-
vice, and Sonotech believes the technology is ready to be used
for the full-scale incineration of contaminated solids, liquids,
sludges, and medical wastes. Coal and contaminated soil, sludge,
and tar samples collected from two Superfund sites were blended
for use in this SITE demonstration.
2.5 Key Features of the Sonotech Cello®
Pulse Combustion System
The Sonotech Cello® pulse combustion system typically con-
sists of an air inlet, a combustor section, and a tailpipe. In the
Sonotech pulse combustor, fuel oxidation and heat release rates
vary periodically with time, producing periodic variations or
pulsations in pressure, temperature, and gas velocity (see Figure
2). Sonotech claims that large-amplitude resonant pulsations
excited by its frequency-tunable pulse combustor can signifi-
cantly improve an incinerator's performance, thereby reducing
capital investment and operating costs for a wide variety of in-
cineration systems.
2.6 Availability and Transportability of
Equipment
The Cello® pulse combustion system is available from
Sonotech, Inc., of Atlanta, GA (see Section 1.5 for address and
telephone number). The system can be designed as a retrofit to
existing incinerators or can be designed as an integral compo-
nent of a new incinerator. For most applications, the Sonotech
system can be transported in a medium-duty truck.
11
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Secondary
burner
To air pollution
control systems'
Sonotach Tunable-Pulse
Bumor
Figure 1. Sonotech Cello® Pulse Combustion Burner System fitted to the IRF RKS.
2.7 Materials-Handling Requirements
Materials-handling requirements for an incinerator are not
affected by using the Sonotech system; however, the Sonotech
system may result in an increased feedrate to the incinerator.
The Sonotech system generates noise in the 100-dB range. In
a typical work environment, noise levels may be high enough to
cause concern. Sonotech can enclose the system in sound-insu-
lating material to reduce the noise intensity, or the entire
incinerator may be enclosed to reduce the noise.
2.8 Site-Support Requirements
Use of the Sonotech unit requires natural gas, fuel oil, or an-
other energy source; an air or oxygen source; and an electrical
connection. The amounts of these three consumable requirements
arc comparable to those needed for a similar sized burner.
2.9 Limitations of the Technology
The Sonotech Cello® pulse combustion system has the same
limitations as a nonpulsating burner attached to a combustion
device. As mentioned above, the system produces considerable
noise, which may be controlled by sound insulation.
12
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Air flapper valve
Fuel flapper \ J /*
valve x If [
\
Inlet
Section
Combustion and expansion of
gases
Combustion
Section
Exhaust pipe
Exhaust
section
Flappers open and
admit reactants
atmospheric
Combustion
Emptying phase of
the combustor
Reactants enter
and gases leave
the combustor
- Valves close, gases —
reenter the combustor,
and combustion occurs
Time
Figure 2. Key features of the Sonotech Cello® Pulse Combustion System.
13
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Section 3.0
Economic Analysis
3.1 Introduction
This economic analysis presents a cost estimate for installing
and operating the Sonotcch Cello® pulse combustion burner.
Cost data were compiled during a SITE technology demonstra-
tion at the EPA IRF in Jefferson, AR, and from information
obtained from the technology developer. Costs have been esti-
mated for 12 categories applicable to typical cleanup activities
at Supcrfund and RCRA sites (Evans 1990). Costs are presented
in March 1995 dollars and are considered to be order-of-magni-
tudc estimates with an expected accuracy between 50% above
and 30% below the actual costs.
This section discusses issues and assumptions used to define
a typical-use scenario for this technology, the analysis of each
of the 12 cost categories, and conclusions of this analysis.
3.2 issues and Assumptions
This section summarizes the major issues and assumptions
used in the economic analysis of the Sonotech technology. Is-
sues and some assumptions are presented in text; major
assumptions are presented as bullets at the end of Sections 3.2.1
and 3.2.2. In general, pulse combustion burner operating issues
and assumptions are based on information obtained from and
Observations made during the Sonotech SITE demonstration.
Certain assumptions were made to account for variable incin-
erator parameters; others were made to simplify cost estimating
for situations that would actually require complex engineering
or financial functions.
3,2.1 Equipment and Operating
Parameters
The Sonotech system can be used in a variety of combustion
processes. The system incorporates a combustor that can be tuned
to Induce large-amplitude sonic pulsations inside combustion
process units such as boilers or incinerators. These pulsations
increase heat release, mixing, and mass transfer rates in the com-
bustion process, resulting in faster and more complete
combustion. TheSITE demonstration showed that the pulse com-
bustion burner system increased the feedrate of a pilot-scale
incinerator by 13% to 35%. It is assumed that this same feedrate
increase will be observed on a full-scale incinerator. The system
can be used to treat any material typically treated in a conven-
tional incinerator, including soils, sludges, medical wastes, and
liquids contaminated with volatile organic compounds (VOC)
or semivolatile organic compounds (SVOC).
Sonotech will configure the pulse combustion burner system
to accommodate the operating parameters of a customer's exist-
ing incinerator. Because the operating parameters and costs for
an incinerator can vary greatly depending on the incinerator type,
energy used, media to be treated, and regulatory requirements,
determining the exact costs associated with the application of
the Sonotech system can be difficult. To assist the decision maker,
a worksheet has been provided in Section 3.4, Conclusions of
Economic Analysis, to allow the operator of an existing incin-
erator to compare current operating costs with the operating costs
of the incinerator retrofit with the Sonotech system.
Equipment and operating parameter assumptions include the
following:
• The pulse combustion burner equipment is retrofit to an
existing incinerator by Sonotech personnel.
• The Sonotech system is configured for an incinerator that
has a feedrate of 2 tons per hour and operates at 30 million
Btu/hr.
• The Sonotech system increases the waste feedrate by 15%
above the normal feedrate, observed at the Sonotech SITE
demonstration.
• The Sonotech system is operated 24 hours per day, 7 days
per week, with an on-line operating efficiency of 80%; there-
fore, real operating time is 42 weeks per year.
• The Sonotech system operates automatically, requiring no
additional labor efforts.
• No additional air emission monitoring is necessary. The
system uses existing incinerator monitoring equipment and
does not generate emissions requiring additional monitor-
ing equipment.
• Very minimal additional space is needed to house the tech-
nology.
14
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3.2.2 A dditional Assumptions
The following additional assumptions were used in this eco-
nomic analysis:
• The existing incinerator is located 500 miles from the
Sonotech facility, requiring that the Cello® pulse combus-
tion burner be transported 500 miles.
• The medium to be treated consists of soil contaminated with
naphthalene at 10,000 milligrams per kilogram (mg/kg) and
benzene at 30,000 mg/kg, which is similar to the type and
concentration of contaminants in the SITE demonstration
soil.
• The Sonotech system meets treatment goals for the soil.
• All costs are rounded to the nearest $100.
3.2.3 Financial Calculations
When estimating costs for a capital investment, depreciation
should be considered. Depreciation measures the value of the
physical capital a firm uses in its production as that capital is
"used up." Because depreciation of capital costs can be claimed
as a tax deduction, it provides a means for a firm to recover
some of its capital cost. For this analysis, a straight-line depre-
ciation method was used. This method assumes that the value of
the capital is deducted in equal installments over the 3-year life
of the equipment. For further discussion of the depreciation as-
sociated with the Sonotech system, see Section 3.3.4, Equipment
Costs.
a fully loaded labor rate of $40 per hour, the total permitting and
regulatory costs are estimated to be $1,000.
3.3.3 Mobilization and Start-Up Costs
Mobilization and start-up costs include the costs of transport-
ing the Cello® pulse combustion burner equipment to the
incinerator, assembling the system, and performing the initial
shakedown of the system. Sonotech provides trained personnel
to assemble and shake down the treatment system; these person-
nel are assumed to be trained in hazardous waste site health and
safety procedures. Initial operator training is needed to ensure
safe, economical, and efficient operation of the system. Sonotech
provides up to 40 hours of initial operator training to its clients
at no additional cost.
However, the client will incur the labor costs associated with
the trainees attending a 40-hour-course. This analysis assumes
that two operators per shift plus an additional backup person
will receive the training. This will result in a total of 9 people
attending the training course. Assuming that the employees earn
a fully loaded rate of $35 per hour, the client will incur a cost of
$12,600 as a result of training its employees to operate the
Sonotech system.
Transportation costs vary depending on the location of the
existing incinerator in relation to the Sonotech facility. For this
analysis, the equipment is assumed to be transported 500 miles.
Sonotech typically retains the services of a cartage company to
transport all pulse combustion burner equipment. Based on these
parameters, cartage companies currently charge $1.00 per mile,
3.3 Cost Categories
Cost data associated with the Sonotech technology has been
assigned to the following 12 cost categories: (1) site prepara-
tion, (2) permitting and regulatory costs, (3) mobilization and
start-up, (4) equipment, (5) labor, (6) supplies, (7) utilities, (8)
effluent treatment and disposal, (9) residual waste shipping and
handling, (10) analytical services, (11) equipment maintenance,
and (12) demobilization. Each of these cost categories is dis-
cussed below. Table 3 presents a breakdown of the costs assigned
to each of the 12 categories.
3.3.1 Site Preparation Costs
Site preparation costs include administration, treatment area
preparation, and treatability study costs. For this analysis, site
preparation costs are $0 because the Sonotech system is mounted
to an existing incinerator, and no additional construction costs
are incurred.
3.3.2 Permitting and Regulatory Costs
Permitting and regulatory costs are incurred for the operation
of an incinerator. This analysis assumes that for an existing RCRA
incinerator, required permitting and regulatory costs have already
been incurred. However, according to 40 CFR Part 270.42, the
addition of the Sonotech system to an existing RCRA incinera-
tor would be classified as a Class 2 permit modification. As a
result, about 24 hours would be spent addressing the regulatory
requirements associated with such a modification. Therefore, at
Table 3. Costs Associated with the Sonotech Technology
Cost Category Expenses'
Site Preparation
Permitting and Regulatory Costs
Mobilization and Start-Up
Equipment"
Labor
Supplies
Utilities
Effluent Treatment and Disposal
Residual Waste Shipping and Handling
Analytical Services
Equipment Maintenance
Demobilization
Total Costs for the Useful Life of the Equipment
Average Annual Operating Costs
$0
1,000
13,100
36,000
0
0
0
0
0
0
3,800
0
$53,900
$18,000
"Costs are in March 1995 dollars.
"After depreciation.
15
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for a toial cost of $500. Because the system is not very heavy, it
could be picked up and transported in a standard pickup truck.
3.3.4 Equipment Costs
Equipment costs consist of the purchase cost of the Cello®
pulse combustion burner system. For this analysis, Sonotech
estimates a base cost of $60,000 for the capital equipment needed
for a system configured for a 30-million Btu/hr incinerator. The
equipment has an estimated operational life of 3 to 5 years and
no salvage value. After adjusting equipment costs for deprecia-
tion, the effective cost of the system is $36,000. Table 4 details
the corporate income tax savings resulting from equipment de-
preciation over 3 years.
3.3.5 Labor Costs
Once the Sonotech system is functioning, it is assumed to
operate continuously at the designed feedrate, except during rou-
tine maintenance conducted by Sonotech over the life of the
equipment (see Section 3.3.11, Equipment Maintenance Costs).
No labor costs arc incurred beyond those necessary to operate
the existing incinerator.
3.3.5 Supply Costs
The Sonotech system operates continuously using a combus-
tor that can be tuned to induce large amplitude sonic pulsations
inside combustion process units. Therefore, no direct supply costs
are expected to be incurred beyond those necessary to operate
the existing incinerator.
3.3.7 Utility Costs
The energy requirements of the Sonotech system are less than
5,000 kilowatt hours (kWh) per year. In addition, the improved
heat transfer produced by the system may increase the rate of
drying and heating the waste, which in turn would increase the
burn rate and reduce the total fuel consumption of an incinera-
tor. Actual energy consumption will vary among incinerators and
therefore is difficult to estimate for this analysis. However, be-
cause the relative change in costs is assumed to be negligible,
this analysis assumes no additional utility costs.
3.3.8 Effluent Treatment and Disposal
Costs
No costs are incurred for effluent treatment and disposal, be-
cause the Sonotech system does not produce an effluent.
Table 4. Equipment Depreciation
Depreciation Deduction for
Year Tax Purposes
Income Tax Savings at
Corporate Rate of 40%
1
2
3
320,000
S20.000
S20.000
$8,000
58,000
58,000
3.3.9 Residual Waste Shipping and
Handling Costs
The Sonotech system increases an existing incinerator's
feedrate, which in turn increases the volume of incinerator ash
requiring disposal. However, for this analysis, this increased
volume will not be attributed to the Sonotech system. As a re-
sult, no additional costs for residual waste shipping and handling
are incurred, because the same quantity of incinerator ash is pro-
duced by a conventional incinerator as by the same incinerator
equipped with the Sonotech system.
3.3.10 Analytical Service Costs
Sampling frequency and sample quantities are incinerator-spe-
cific and are based on regulatory agency requirements. Sampling
and analytical costs are typically associated with operating an
incinerator; however, no additional sampling and analytical costs
would be incurred by operating an incinerator equipped with the
pulse combustion burner.
3.3.11 Equipment Maintenance Costs
Sonotech estimates that 25 hours of maintenance labor is
needed annually for its system. This maintenance is performed
by a technician at a fully loaded rate of $25 per hour, including
overhead and fringe benefits. Replacement parts for the Sonotech
system are covered for one year under an equipment warranty.
After the initial year, replacement parts are estimated to cost
about $1,000 per year. Based on these assumptions, annual main-
tenance costs are estimated to be $625 for the first year and $ 1,625
for each year thereafter.
3.3.12 Demobilization Costs
Demobilization includes (1) treatment system shutdown, dis-
assembly, and decontamination; (2) site cleanup and restoration;
and (3) transportation and disposal of equipment off site. For
this analysis, site demobilization costs for the Sonotech system
are assumed to be $0, because the existing incinerator will be
demobilized regardless of whether it is retrofit with the pulse
combustion burner system.
3.4 Conclusions of Economic Analysis
This analysis presents a cost estimate for treating VOC- and
SVOC-contaminated soil with the Sonotech technology. The
Sonotech system increases the heat release and mass transfer
rates in the combustion process, which results in faster and more
complete combustion. As a result, the system is capable of in-
creasing the feedrate by about 15%.
The total estimated capital costs are about $53,900. Of this,
about $36,000, or nearly 67%, is for the capital equipment when
the Sonotech system is retrofit to an existing incinerator, or speci-
fied on new incinerator construction plans. As a result, annual
operating and maintenance costs are relatively low because the
system uses the labor and energy requirements of the existing
incinerator. The Sonotech system has an expected operating life
of three years.
16
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Operating conditions, costs, and revenues vary extensively
among incinerators. As a result, this analysis provides a worksheet
for individual incinerator operators to perform a site-specific
cost-benefit analysis. By using real operating costs, an operator
can analyze the impact the Sonotech system will have on the
incinerator system's profits. Table 5 is provided as a worksheet
for the incinerator operator. By inserting the appropriate infor-
mation, the operator can estimate the profit margin for an
incinerator with and without the Sonotech system.
Tables. Worksheet
Instructions
1 . Fill in the current tons per year treated by the incinerator.
2. Fill in the cost charged to a client to treat 1 ton of waste.
3. Multiply line 1 by line 2 to obtain the current annual
revenue realized by the incinerator.
4. Fill in the current annual operating expenses for the
incinerator.
5. Subtract line 4 from line 3 to obtain the current annual
incinerator profit. This figure is used below for
comparison purposes.
6. Multiply line 1 by 1 .15 to obtain the amount of waste that
can be treated per year by the incinerator equipped with
the Sonotech system.
7. Fill in the cost charged to a client to treat 1 ton of waste.
8. Multiply line 6 by line 7 to obtain the new annual revenue
generated by the incinerator equipped with the Sonotech
system.
9. Fill in the current annual operating expenses for the
incinerator.
10. This line represents the average annual operating costs
for the Sonotech system.
11 . Add lines 9 and 10 to obtain the expected annual
operating expenses for the incinerator equipped with the
Sonotech system.
12. Subtract line 11 from line 8 to obtain the annual revenue
generated by the incinerator equipped with the Sonotech
system.
13. Subtract line 5 from line 12. If the result is positive, it is
the additional annual profit that will be generated by
installing the Sonotech system. If the amount is negative,
it is the additional annual cost that will be incurred by
installing the Sonotech system.
Operator
Estimates3
$18,000
Examples
40,320
$300
$12,096,000
$12,000,000
$96,000
46,368
$300
$13,910,400
$12,000,000
$18,000
$12,018,000
$1,892,400
$1 ,796,400
"This worksheet is provided to help incinerator operators calculate preliminary cost estimates for using the Sonotech system. To formulate more
precise cost estimates, Sonotech can be contacted to obtain direct equipment costs.
17
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Section 4.0
Treatment Effectiveness
Prior to its closure, EPA conducted experimental small-scale
and pilot-scale studies at its IRF in Jefferson, AR. The facility
housed a pilot-scale RKS and various associated waste handling,
emission control, process control, and safety equipment, as well
as a bench-scale thermal treatment unit used to conduct thermal
trcatabHity studies on a smaller scale. The purpose of the re-
search facility was to support regulatory development and
technology assessment underRCRA.TSCA, and CERCLA. Over
the past few years, the IRF extended its role by conducting in-
cineration test programs for the Departments of Defense and
Energy (DoD and DOE).
The Sonotech pulse combustor test program was performed
using the RKS, which consisted of a rotary Mln primary com-
bustion chamber, a transition section, and a fired afterburner
chamber. After exiting the afterburner, flue gas flowed through
a quench section followed by the primary APCS. The primary
APCS for these tests consisted of a venturi/packed-column wet
scrubber system, followed by a baghouse. Downstream of the
primary APCS, a secondary APCS consisted of a demister, an
activated-carbon adsorber, and a HEPA filter. The backup APCS
was designed to ensure that organic compound and paniculate
emissions to the atmosphere are negligible.
During this demonstration, the IRF maintained a complete,
analytical laboratory for analysis of VOCs and SVOCs using
EPA SW-846 methods. The analytical laboratory was supported
by a complete array of flue gas sampling equipment and con-
tinuous flue gas analyzers. In addition, the IRF was supported
by a full complement of engineering, analytical, and technician
staff.
This section discusses the treatment effectiveness of the
Sonotech system and provides specific information on the dem-
onstration objectives and approach; demonstration procedures,
including waste preparation, demonstration design, sampling and
analysis, and quality assurance and quality control (QA/QC);
and demonstration results and conclusions.
4.1 Demonstration Objectives and
Approach
The general objective of the Sonotech SITE demonstration
was to develop data needed to allow an unbiased, quantitative
evaluation of Sonotech's claims regarding the pulse combustion
technology (see Section 1.4). The focus of the program was to
evaluate the developer's claims that the technology lowers com-
bustion pollutant emissions and that it increases an incinerator's
treatment capacity. Test program data were also developed to
evaluate whether the Sonotech technology affects (1) trace metal
partitioning in the incinerator, (2) the leachability of trace met-
als in incinerator waste streams, and (3) the severity of transient
puffs.
To evaluate Sonotech's claims, data were developed to deter-
mine whether, compared to convention combustion, applying
pulse combustion technology to the IRF RKS resulted in the
following:
• Increased incinerator capacity
• Increased POHC DREs
• Decreased flue gas CO emissions
• Decreased flue gas NOx emissions
• Decreased flue gas soot emissions
• Decreased combustion air requirements
• Decreased auxiliary fuel (natural gas) requirements
The secondary test program objectives required developing
data to evaluate whether the application of the Sonotech tech-
nology, compared to conventional combustion, resulted in the
following:
• Reduced magnitude of transient puffs of CO and TUHC
• Reduced incineration costs
• Significant changes in the distribution of hazardous con-
stituent trace metals among the incinerator discharge streams
(kiln bottom ash, scrubber liquor, and baghouse exit flue
gas)
• Significant changes in the leachability of TCLP trace met-
als in kiln ash
The specific procedures taken to achieve the demonstration
objectives are described in Section 4.2 below. During the dem-
onstration, observations were also made about the reliability and
18
-------
cost of the Sonotech system. To address the test program objec-
tives, tests at four different incineration system operating
conditions were performed. These test conditions are discussed
in Section 4.2.
4.2 Demonstration Procedures
During the demonstration, three tests were performed for each
of four different incineration system operating conditions, for a
total of 12 tests. To evaluate the developer's claims, the test matrix
was designed to yield the following types of data:
• Emissions
• POHC DREs
• Metals partitioning
• Metals teachability
The four incineration system operating conditions provided
data for the following test conditions:
• Test Condition 1
- Conventional combustion
- Typical, baseline, effectively controlled incinerator
operation
• Test Condition 2
- Conventional combustion
- Maximum waste feed rate under conventional com-
bustion, which typically approaches noncompliance
with permit limits
• Test Condition 3
- Sonotech pulse combustion
- Feed rate identical to Test Condition 2
• Test Condition 4
- Sonotech pulse combustion
- Maximum waste feed rate under Sonotech pulse
combustion
4.2.1 Waste Preparation for the
Demonstration
The waste feed for all tests consisted of a mixture of contami-
nated materials from two MGP Superfund sites. One component
of the test feed material was a combination of pulverized coal
and contaminated sludge waste from the Peoples site in Dubuque,
IA. Sludge waste at this abandoned MGP site contained high
concentrations of coal tar constituents. The test feed material
also consisted of contaminated soil borings and a tar waste ob-
tained from an oil-gasification MGP site in the southeastern U.S.
A mixture of coal and sludge was prepared at the Peoples site
in September 1993. The mixture consisted of 65% to 70% coal
and 30% to 35% sludge. The mixture was prepared by using a
skip loader to place respective proportions of sludge and coal on
a pad, then mixing and grinding the combination. The material
was then screened through a 2.5-inch-mesh screen, transferred
to 20 55-gallon drums and shipped to the IRE
Initial scoping tests consumed more of the material originally
shipped from the Peoples site material than intended. The initial
scoping tests were aimed at identifying test material feed rates
and incinerator operating conditions that would yield the emis-
sions characteristics desired for the four test conditions. Because
the scoping tests consumed too much material, a new mixture
was prepared by adding additional coal from the Peoples site to
the original mixture; the new coal was added in the proportion
of 0.41 kilograms (kg) of coal to 1.0 kg of original Peoples site
mixture.
Operational and sample integrity problems resulted from ini-
tial attempts to complete one set of demonstration tests (a set
includes one test under each of the four planned test conditions
with three sets comprising the intended triplicate testing). Be-
cause the initial test attempts had to be repeated, additional test
feed material had to be identified.
The additional test material consisted of contaminated soil
borings and a tar waste from an oil gasification process at an
MGP site in the southeastern U.S. The following quantities of
waste were shipped to the IRF to complete the demonstration
tests:
• Seven 55-gallon drums containing 2,900 pounds (1,320 kg)
of soil borings not considered hazardous waste
• Six 55-gallon drums containing 2,700 pounds (1,230 kg) of
soil borings contaminated with S VOCs and VOCs, includ-
ing benzene, toluene, ethylbenzene, and xylenes
(BTEX)—having the toxicity characteristic for benzene
(hazardous waste code D018)
• Nine 55-gallon drums containing 4,500 pounds (2,050 kg)
of tar waste having the characteristic of ignitability (D001)
and toxicity for benzene (D018) and cresol (D026).
The feed material used to complete the test program was a
combination of the coal-sludge mixture and a mixture of the soil
and tar.
For the first incomplete set of demonstration tests, fiberboard
containers (cardboard boxes) were packaged to contain 4.5
pounds (2.1 kg) of coal-sludge mixture combined with a ben-
zene-naphthalene spike solution. Components in each fiberboard
container included the coal-sludge mixture, the benzene-
naphthalene spike, the polyethylene (PE) bottle containing
the spike, and the PE bag liner for the container. The total heat
content of a filled fiberboard container was about 49,300 Brit-
ish thermal units (Btu) (52.0 megajoules [MJ]). Batch
charges—consisting of two of these containers, or almost 100,000
Btu (106 MJ) per batch charge—were fed at variable frequen-
cies to achieve target test conditions.
19
-------
The second set of demonstration tests was conducted on a
mixture that included the newly acquired MGP wastes (which
consisted of soil and tar). Exploratory experiments revealed that
the fiberboard containers could each hold enough of the soil-tar-
coal-sludge mixture and the benzene-naphthalene spike to
provide up to 100,000 Btu (106 MJ) per container.
The mixture used was packaged in 1.5-gallon (5.7-liters) fi-
berboard containers for batch feeding to theRKS. Each container
was filled with the following:
• 4.5 pounds (2.1 kg) of coal-sludge mixture
• 3.0 pounds (1.4 kg) of tar
• 3.5 pounds (1.6 kg) of soil (equal weight of hazardous and
nonhazardous soil)
* 0.18 pounds (81.6 grams) of spike solution contained in the
high density polyethylene (HDPE) bottle
• The polyethylene liner.
The spike solution consisted of a 25-weight-percent solution
of naphthalene in benzene (20.4 grams of naphthalene per 81.6
grams of solution). To prepare each fiberboard container, it was
first filled with the specified weight of each test material feed
component. The bottle of spike mixture was then imbedded in
the feed mixture, and the container's double-thick PE liner was
sealed with a plastic tie. The fiberboard container was then closed
and sealed with paper packaging tape.
4.2.2 Demonstration Design
As discussed in the introduction to this section, tests were
performed under four different incineration operating conditions
to address the demonstration objectives.
The waste feed was prepared as described in Section 4.2.1
and was batch fed to the RKS via its ram-feed system. The tar-
get feedrate for each of the four test conditions were as follows:
• Test Condition 1:61.1 Ib/hr (27.8 kg/hr)
• Test Conditions 2 and 3:74.7 Ib/hr (33.9 kg/hr)
• Test Condition 4: 84.0 Ib/hr (38.2 kg/hr)
The test feed frequency was designed to operate within the
IRF's permit-required CO emission level of 100 ppm on a 1-
hour rolling average basis. A 50-ppm, 1-hour rolling average
was used as the waste feed cutoff point to ensure a safety mar-
gin. Kiln exit gas temperature was nominally 1,700 degrees
Fahrenheit (°F) (927 degrees Celsius [°C]) and the oxygen con-
centration was nominally 10%. Afterburner exit gas was
nominally 2,000°F (1,090°C) and the oxygen concentration was
nominally 8%.
Beginning on the day before each demonstration test, the RKS
was fired with natural gas to bring it to steady state operation at
the desired conditions. The Sonotech burner was also fired prior
to test days scheduled for pulse combustion testing, although
pulsations were not initiated until the test Test material feed
was then initiated, and steady RKS operation was established.
Kiln and afterburner fuel and air flows, along with secondary
combustion air flow, were controlled to give the desired tem-
perature and excess air conditions. Flue gas sampling (see Section
4.2.3) began no sooner than 1.5 hours after the initial waste feed.
Feed was continued until flue gas sampling was completed. The
ash auger transfer system on the kiln continuously removed kiln
ash from the kiln ash hopper and deposited it into clean 55-gal-
lon drums.
After each test, ash from each test was weighed and sampled
for analyses. Baghouse ash and scrubber liquor samples were
also collected at the end of each test for analyses. Analytical
protocols are described below in Section 4.2.3.
For all tests, the incinerator operating parameters were recorded
using an electronic data acquisition system; operating param-
eters were also recorded manually at a minimum of every 15
minutes.
4.2.3 Sampling and Analysis Program
The Sonotech technology demonstration was conducted over
a 4-month period. This section describes the sampling and analy-
sis program associated with the demonstration. It also discusses
field and laboratory QA/QC procedures, deviations from meth-
ods and procedures outlined in the Sonotech quality assurance
project plan (QAPP) (Acurex and PRC 1994), and any impact
the deviations may have had on project objectives.
Figure 3 depicts RKS sampling types, locations, and meth-
ods. For all tests, the following sampling activities were
performed:
• Obtain a composite sample of the kiln ash discharge
• Obtain a composite sample of the scrubber system liquor
• Obtain a composite sample of the baghouse flyash
• Continuously measure the following components of the flue
gas:
- oxygen concentrations in the kiln exit flue gas
- oxygen, CO, carbon dioxide (CO2), NOx, and TUHC
concentrations in the afterburner exit flue gas
- oxygen, CO2, and NOx concentrations in the baghouse
exit flue gas
- oxygen and CO concentrations in the stack gas
• Collect a gram-sized sample of afterburner exit particulate
using the EPA Method 17 sampling train
• Sample flue gas at the afterburner exit and baghouse exit
for trace metals using the EPA Method 29 multiple metals
sampling train
• Sample flue gas at the baghouse exit for mercury using EPA
Method 101A
20
-------
>
Kiln
After-
burner
T*
Flue gas
quench
Venturi
scrubber
\
Packed
column
scrubber
|
i
5
Flue gas
heat
Baghouse
•I-*-
Carbon
bed
HEPA
filter
Sampling points
1. Feed
2. Kiln ash discharge
3. Kiln exit flue gas
4. Afterburner exit flue gas
5. Scrubber liquor
6. Baghouse hopper
7. Baghouse exit flue gas
8. Stack gas
Total
feed
material
X
Kiln
ash
X
Scrubber
liquor
X
Bag-
house
.ash
X
o,
X
X
X
X
CO
X
X
CO2
X
X
NOX
X
X
Heated
TUHC
X
High-volume
Method 17,
particulate
X
EPA multiple
metal train,
test trace
metals
X
X
Method
101 A
mercury
X
MethodOOW,
test semlvolatile
POHCsand
PAHs
X
X
Method 0030,
volatile
organic
constituents
X
X
Method 23,
PCDD/
PCDF
X
Methods,
particulate
andHCI
X
X
Figure 3. Block diagram of Rotary Kiln System sampling locations, types, and methods.
-------
• Sample flue gas at the afterburner exit and baghouse exit
for scmivolatile POHCs and other polynuclear aromatic
hydrocarbon (PAH) constituents using theEPAMethod 0010
train
• Sample flue gas at the afterburner exit and baghouse exit
for VOCs using the EPAMethod 0030 volatile organic sam-
pling train (VOST)
• Sample flue gas at the baghouse exit for PCDDs and PCDFs
using EPA Method 23
• Sample flue gas at the baghouse exit and the stack for par-
Uculate and hydrogen chloride using EPA Method 5 (stack
sampling is needed to comply with IRF permitrequirements)
No feed material sample was collected for any test. Instead,
feed material component samples were collected for analysis by
preparing all test feed material fiberboard containers to contain
four feed components and a benzene-naphthalene spike. The four
components were added sequentially to each fiberboard con-
tainer: a coal-fortified coal-sludge mixture from the Peoples site,
two different mixtures of soil borings from an MGP Superfund
site in the southeastern U.S., and an oil gasification process tar
from the southeastern MGP site. The coal-sludge and soil com-
ponents were each mixed to ensure that all fiberboard containers
were filled with the most uniform feed composition that could
be practically achieved. Tar from the site was collected in a man-
ner that produced a uniform composition among all shipping
containers of tar received and targeted for use in demonstration
tests.
During the test program, three samples of each feed compo-
nent were collected—one for each of the three sets of tests
comprising the triplicate test program. Each set of tests consisted
of four tests—one at each of the four specified conditions. About
midway through the packaging exercise for each test set, one
fiberboard container was charged with only the coal-sludge mix-
ture and was set aside. Another container was filled with each
soil component; the soil components were then mixed by
hand-kneading the plastic bag liner, and the container was then
set aside. Near the midpoint of adding tar to the fiberboard con-
tainers of coal-sludge and soil, a 1-liter sample container was
filled with tar to represent the tar component sample for the test
set. The samples were then taken to the on-site laboratory for
subsequent aliquot splitting and aliquot preservation for ship-
ment or analysis.
Kiln bottom ash was continuously removed from the RKS
ash pit by the ash auger system and was deposited in a 55-gallon
drum. Kiln ash was collected in one drum during initiation of
each test run before the start of flue gas sampling. A new ash
collection drum was used to collect kiln ash during the flue gas
sampling. The flue gas sampling time period is the time of the
actual test run. After the flue gas sampling was completed, the
collection drum was removed. The entire fraction of kiln ash
collected during the sampling period was split into two parts
that were about equal. One part was stored, as is, in appropriate
jars. Aliquots for volatile organics analysis were drawn from
this fraction. The remaining ash was ground overnight in a 55-
gallon rotating-drum grinding machine. Aliquots for ash analyses
other than volatile organics were drawn from the ground ash
fraction. The ash was ground to ensure maximum homogeneity
in the collected sample. The unground fraction was later ground
by the external laboratory conducting the VOC analyses.
For all test runs, the RKS scrubber system was operated at as
close to total recirculation (zero blowdown) as possible. After
each test run, the scrubber system was drained to a collection
tank. Composite post-test scrubber liquor samples were collected
from a tap in the recirculation loop immediately before draining
the system. After draining, the scrubber system was recharged
with fresh makeup water for the next test run. For each test run,
pre-test scrubber liquor samples were collected from the recir-
culation loop tap immediately before the start of test material
feeding for the test.
Gram quantities of baghouse ash were collected for all tests.
The entire amount collected was used for analysis.
The Method 5 trains for particulate and hydrogen chloride
collection had dilute caustic-filled impingers (0.1 normal sodium
hydroxide). Both hydrogen chloride and chlorine from the flue
gas were collected in the impingers. This provided a conserva-
tive estimate of hydrogen chloride concentrations (hydrogen
chloride plus chlorine) and satisfied test program objectives. Over
about a 1-hour period, a nominal 50-cubic-foot (ft3) (1.4-
cubic-meter [m3]) sample was collected at the two locations
sampled. The Method 0010, Method 23, Method 101A, and
multiple metals trains sampled 100 ft3 (2.8 m3) of flue gas over a
3-hour period. Because mercury was measured using a separate
sampling train, the permanganate impingers for mercury collec-
tion were not used in the multiple metals trains, and sample
recovery steps from these trains—specified for eventual mer-
cury analysis—were not performed. Four Method 0030 trap pairs
each sampled 20 liters of flue gas. Four additional trap pairs were
taken as insurance against trap breakage.
Throughout the demonstration CEM data were recorded con-
tinuously on strip charts and by two automatic data acquisition
systems. Figure 4 depicts the generalized flue gas and CEM gas
flow.
Test program samples were analyzed for matrix-specific com-
binations of the following:
• Semivolatile POHCs and PAH constituents
• Volatile organic constituents
• PCDDs/PCDFs
• Contaminant trace metals
• Total organic carbon
• Chloride
• Moisture
• Heat content
• Carbon, hydrogen, oxygen, nitrogen, and sulfur
22
-------
T
Condensate
removal
Sample
port
Store room
Calibration 1
sas J
Control room
Vent
Heated
sample
line
-Xh
Figure 4. Generalized flue gas and CEM gas flow schematic.
23
-------
Table 6 lisls volatile organic, semivolatile organic, and trace
metal target analytes. Table 7 summarizes the number of test
program sample analyses. As indicated in Table 7, samples of
most sample matrices were analyzed for each of the 12 test runs
(three runs at each of four test conditions) completed. However,
as the test feed material was the same for the 12 test runs, only
four samples of each of the components of this material, includ-
ing one duplicate pair, were collected and analyzed. Also prepared
were TCLP leachates of each test's kiln ash, post-test scrubber
liquor, baghouse ash, and four of each of the three feed compo-
nents (plus a duplicate series of samples). Table 8 summarizes
analytical protocols for the various samples. The sample aliquot
schedules and custody, storage, and shipment procedures were
followed according to test protocols.
4.2.4 Quality Assurance and Quality
Control Program
QC checks and procedures were an integral part of the
Sonotcch SITE demonstration to ensure that QA objectives were
met. These checks and procedures focused on (1) the collection
of representative samples that were free of external contamina-
tion and (2) the analysis of comparable data. Two kinds of QC
checks and procedures were conducted during the demonstra-
tion: (1) checks controlling field activities, such as sample
collection and shipping, and (2) checks controlling laboratory
activities, such as extraction and analysis. A detailed discussion
of the QA/QC program is provided in the SITE Program Evalu-
ation of the Sonotech Pulse Combustion Burner Technology
report (EPA 1996).
4.3 Demonstration Results and
Conclusions
This section discusses the operating conditions, demonstra-
tion results, data quality, and conclusions of the SITE
demonstration of the Sonotech system. The SITE demonstra-
tion provides the most extensive Sonotech performance data to
date and serves as the foundation for conclusions on the system's
effectiveness and applicability. Demonstration results have been
supplemented by information provided by the vendor.
4.3.1 Operating Conditions
Four incineration system operating conditions were tested
during the demonstration (see Section 4.2). After preparing the
waste feed (see Section 4.2.1), the test material was batch fed to
thcRKS ram-feed system. The test feedrate (or charge frequency)
and RKS operating conditions were determined from scoping
tests and are described in detail later in this section. One factor
influencing the maximum feedrate was the IRF permit limit
maximum CO emission level of 100 ppm on a 1-hour rolling
average basis. When a relatively high heat content material is
being fed, the maximum allowable waste feedrate is established
based on the incidence of puffs of incompletely combusted or-
ganic constituents (primarily CO and TUHC) that survive the
burner. A 50-ppm, 1-hour rolling average was used as the waste
feed cutoff point to ensure that the CO permit level was not vio-
lated. For example, a feedrate that results in routine stack gas
CO spikes of over 300 ppm, lasting 30 seconds or more, and
also leading to a 1-hour rolling average flue gas CO levels ap-
proaching 50 ppm would be the maximum tolerated to be
characterized as an acceptable operation. The temperature of the
kiln exit gas was nominally 1,700°F (927°C), and the oxygen
concentration was nominally 10%. Afterburner exit gas tempera-
ture was nominally 2,000°F (1,090°C) and oxygen concentration
was nominally 8%.
Scoping tests were performed to define the waste feedrates
corresponding to each condition. The most critical conditions to
define were those for Test Condition 2 and Test Condition 4. Both
of these are defined to be conditions of borderline acceptable
operation. The waste feedrates for these conditions were estab-
lished during scoping tests by increasing the waste feedrate to
the kiln until one or both of the following conditions occurred:
• An unacceptable level and frequency of CO spikes in the
afterburner exit flue gas occurred, causing the hourly aver-
age CO levels to approach 50 ppm corrected to 7% oxygen
• Difficulty in controlling kiln exit gas temperature to the
desired target level
The feedrate for each critical condition was then established
to be just below that associated with one or both of the above
conditions.
The point at which the waste feedrate could not be varied de-
serves emphasis. All demonstration test waste feed material was
packaged into cubical fiberboard containers. Each container was
filled with 11.2 pounds of waste and POHC spike mixture. The
only means of varying waste feedrate was by varying the fre-
quency of container charging to the kiln. In addition, other
constraints were placed on incinerator operation in establishing
waste feedrates. For example, the minimum heat input supplied
to the kiln by auxiliary fuel (natural gas) had to be at least
500 thousand British thermal units per hour (kBtu/hr) (147 kW).
This constraint is an operational safety limit at the IRF. It was
established to ensure that a safe combustion environment always
existed in the kiln.
The target feedrates for each of the four test conditions aris-
ing from the scoping tests are given in Table 9. The table indicates
not only the target feedrate, but also the charge frequency for
each test condition that resulted in that feedrate target. A discus-
sion of scoping test data to show that the selected targets met the
operating condition objectives would be appropriate here. How-
ever, scoping test data reflect shorter term incinerator operation
than occurred during actual demonstration tests, and a more ex-
tensive data base of incinerator operating conditions was
developed while completing the actual demonstration tests.
Therefore, discussion which shows that the selected target
feedrates met the operating condition objectives is presented
below.
Beginning on the day before each demonstration test, the RKS
was brought to steady operation at the desired conditions by fir-
ing only natural gas. The Sonotech burner was also fired prior to
pulse combustion test days, although pulsations were not begun
until the test day. On the test days, waste material was fed into
the system, and steady RKS operation was reestablished. Com-
24
-------
Table 6. Target Analytes
Volatile Organic Analytes
Benzene
Bromodichloromethane
Bromoform
Carbon tetrachloride
Chlorobenzene
Chlorodibromomethane
Chloroethane
Chloroform
Chloromethane
Dibromomethane
1,1-Dichloroethane
1,2-Dichloroethane
1,1-DichIoroethene
trans-1,2-Dichloroethene
1,2-Dichloropropane
cis-1,3-DichIoropropene
trans-1,3-Dichloropropene
Ethylbenzene
Methylene chloride
Styrene
1,1,2,2-Tetrachloroethane
Tetrachloroethene
Toluene
1,1,1 -Trichloroe thane
1,1,2-Trichloroethane
Trichloroethene
1,2,3-Trichloropropane
Vinyl chloride
Xylenes (total)
Semivolatile Organic Analytes
Acenaphthene
Acenaphthylene
Anthracene
Benzo(a)anthracene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(ghi)perylene
Benzo(a)pyrene
Chrysene
Dibenz(a,h)anthracene
Fluoranthene
Fluorene
lndeno(1,2,3-cd)pyrene
2-Methylnaphthalene
Naphthalene
Phenanthrene
Pyrene
Trace Metal Analytes
Antimony
Barium
Beryllium
Mercury
Cadmium
Chromium
Lead
Table 7. Test Program Sample Analysis Summary
Number of Analyses
Sample Matrix
Coal-sludge feed component
Test sample
Split sample
Matrix spike
Spike duplicate
Semivolatile
POHCs and
other PAHs
4
1
1
1
Volatile
Organic
Constituents
4
1
1
1
Trace
Metals3
4
1
1
1
Mercury
4
1
1
1
Total
PCDDs/ Organic
PCDFs Chloride Carbon
Soil feed component
Test sample
Split sample
Matrix spike
Spike duplicate
Tar feed component
Test sample
Split sample
Matrix spike
Spike duplicate
4
1
1
1
4
1
1
1
4
1
1
1
4
1
1
1
(continued)
"Except mercury.
25
-------
Table?. Continued
Number of Analyses
Sainpto Matrix
Kiln ash
Tost somplo
Split sample
Matrix spite
Spite duplicate
Pro-tost scrubber liquor
Tost samplo
Split sample
Matrix spite
Spite duplicate
Post-tost scrubber liquor
Tost sample
Split samplo
Matrix spite
Spite duplicate
Baghouso ash
Tost sample
Split samplo
Matrix spite
Spite duplicate
Semivolatile
POHCs and
other PAHs
12
2
2
2
12
1
1
1
12
2
2
2
12
2
2
2
Volatile
Organic
Constituents
12
2
2
2
12
1
1
1
12
2
2
2
12
2
2
2
Trace
Metals"
12
2
2
2
12
1
1
1
12
2
2
2
12
2
2
2
Mercury
12
2
2
2
12
1
1
1
12
2
2
2
12
2
2
2
Total
PCDDs/ Organic
PCDFs Chloride Carbon
Afterburner oxit participate
Tost sample
Split samplo
Matrix spite
Spiko duplicate
TCLP loachata
Tost food malarial
Kiln ash
Post-tost scrubber
liquor
Baghouso ash
Method blank
Split sample
Matrix spite
Spiko duplicate
Method 0010 train
Tost sample
Rold Wank
Matrix spite
Spiko duplicate
Method 0030 train
Test sample trap
pair*
Fiold blank
Trip blank
Matrix spite
Method 23 train
Test samplo
Reid Hank
12
24
3
3
3
4
12
12
12
2
4
4
4
4
12
12
12
2
4
4
4
72
12
6
6
12
2
2
2
12
1
(continued)
•Except mercury.
Tour trap pairs sampled por location per test. Three trap pairs analyzed; fourth trap pair for breakage contingency.
26
-------
Table 7. Continued
Method 101A train
Test sample
Field blank
Matrix spike
Spike duplicate
Method 5 train impingers
Test sample
Split sample
Field blank
Matrix spike
Spike duplicate
Total
Number of Analyses
Sample Matrix
Multiple metals train
Front half
Test sample
Field blank
Matrix spike
Spike duplicate
Back half
Test sample
Field blank
Matrix spike
Spike duplicate
Semivolatile Volatile
POHCs and Organic Trace
other PAHs Constituents Metals2 Mercury
24
3
3
3
24
3
3
3
Total
PCDDs/ Organic
PCDFs Chloride Carbon
12
2
2
2
132
183
207
159
13
24
2
2
2
2
32
18
"Except mercury.
27
-------
Table 8. Analytical Protocols
Samplo
Tost food
material
components
Tost food
TCLP
toachalQ
Kiln ash
Kitn ash
TCLP
toachato
Pre-tost
scnibbor
liquor
Post-test
scrubber
liquor
Scrubber
RquorTCLP
toachato
Parameter
Proximate analysis (moisture,
volatile matter, fixed carbon, ash)
Elemental analysis
C, H, 0. N, S
Cl
Heating value
Semivolatile organic constituents
Volatile organic constituents
Trace metalsb
Mercury
TCLP extraction
Trace metals6
Mercury
Semivolatile organic constituents
Volatile organic constituents
Trace metals*
Mercury
TCLP extraction
Trace metals*
Mercury
Semivolatile organic constituents
Volatile organic constituents
Trace metals'1
Mercury
Semivolatile organic constituents
Volatile organic constituents
Trace metalsb
Mercury
TCLP extraction
Trace metalsb
Mercury
Analysis Method
ASTM D-5142
ASTM D-3176
ASTM E-442
ASTM D-3286
Soxhlet extraction by Method 3540A, GC/MS analysis by Method
8270A3
Purge and trap GC/MS by Method 8260a
Digestion by the Multiple Metals Filter Method0 or Method 3051",
ICP analysis
Digestion and CVAAS analysis by Method 7471 a
Method 1 31 1a
Digestion by Method 3015, ICP or GFAAS analysis
Digestion and CVAAS analysis by Method 7470a
Soxhlet extraction by Method 3540A, GC/MS analysis by Method
8270Aa
Purge and trap GC/MS by Method 8260a
Digestion by the Multiple Metals Filter Method0, ICP analysis
Digestion and CVAAS analysis by Method 7471 a
Method 1 31 1a
Digestion by Method 3015, ICP or GFAAS analysis
Digestion and CVAAS analysis by Method 7470
Extraction by Method 3520A, GC/MS analysis by Method 8270a
Purge and trap GC/MS by Method 8260a
Digestion by Method 3015, GFAAS or ICP analysis
Digestion and CVAAS analysis by Method 7470
Extraction by Method 3520A, GC/MS analysis by Method
8270A"
Purge and trap GC/MS by Method 8260a
Digestion by Method 3015, GFAAS or ICP analysis
Digestion and CVAAS analysis by Method 7470
Method 1 31 1a
Digestion by Method 3015, ICP or GFAAS analysis
Digestion and CVAAS analysis by Method 7470
Frequency
1 /test mixture
1 /test mixture
1 /test mixture
1/test mixture
1/test mixture
1/test mixture
1/test mixture
1/test mixture
1/test mixture
1/test mixture
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
(continued)
•SW-846 (EPA 1992).
»Sb, Ba. Bo, Cd. Cr..and Pb.
-------
Table 8. Continued
Sample
Baghouse ash
Baghouse ash
TCLP
leachate
Afterburner
exit
particulate
Afterburner
exit flue gas
Baghouse
exit flue gas
Stack gas
Parameter
Semivolatile organic constituents
Volatile organic constituents
Trace metals'1
Mercury
TCLP extraction
Trace metalsb
Mercury
Semivolatile organic constituents
Total organic carbon
Semivolatile organic constituents
Volatile organic constituents
Trace metalsb
Semivolatile organic constituents
Volatile organic constituents
PCDDs/PCDFs
Trace metalsb
Mercury
Particulate
HCI
Patticulate
HCI
Analysis Method
Soxhiet extraction by Method 3540A, GC/MS analysis by Method
8270A*
Purge and trap GC/MS by Method 8260a
Digestion by the Multiple Metals Filter Method0, ICP analysis
Digestion and CVAAS analysis by Method 7471 a
Method 1 31 1a
Digestion by Method 3015, ICP or GFAAS analysis
Digestion and CVAAS analysis by Method 7470
Soxhiet extraction by Method 3540A, GC/MS analysis by Method
8270A
Method 9060a
Soxhiet extraction of Method 0010 samples by Method 3540A
GC/MS analysis by Method 8270Aa
Purge and trap GC/MS analysis of Method 0030 samples by
Method 5041"
Digestion of multiple metals train samples by Multiple Metals
Method" or Method 3015a, GFAAS or ICP analysis
Soxhiet extraction of Method 0010 samples by Method 3540A
GC/MS analysis by Method 8270Aa
Purge and trap GC/MS analysis of Method 0030 samples by
Method 504 1a
GC/MS analysis of Method 23 samples by Method 8290a
Digestion of multiple metals train samples by Multiple Metals
Method0 or Method 3015a, GFAAS or ICP analysis
Sample preparation by Method 101Ad, CVAAS analysis by Method
7470*
Method 5'
1C analysis of impinger solutions by Method 9057°
Method 5e
1C analysis of combined impinger solution by Method 9057a
Frequency
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
3 trap pairs/test
run
1/test run
1/test run
3 trap pairs/test
run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
1/test run
aSW-846 (EPA 1992).
bSb, Ba, Be, Cd, Cr, and Pb.
C40 CFR 266, App. IX.
"40 CFR 61, App. B.
"40 CFR 60, App. A.
29
-------
Table 9. Target Foodrates
Tost
Condition
Description
Target Feedrate,
Ib/hr (kg/hr)
Charge Frequency
(minutes between
charges)
Baseline, typical 61.1(27.8)
incinerator operation
11
Maximum feedrate
operation
Sonotoch pulse
combustor on,
(oodrate same as in
2
Maximum feedrate
operation with
Sonotech pulse
combustor on
74.7 (33.9)
74.7 (33.9)
84.0 (38.2)
Notes: kg/hr * Kilograms per hour
Ib/hr « Pounds per hour
bustion air flows and kiln and afterburner auxiliary burner fuel
(natural gas) were controlled to achieve the desired temperature
and excess air conditions. Flue gas sampling was started no
sooner than 1.5 hours after the start of waste material feed to the
system. The waste feed was continued until all flue gas sam-
pling was completed. For all tests, the scrubber system was
operated at its nominal design settings (see Table 10) and at as
close to total recirculation (zero to minimum blowdown) as pos-
sible. The kiln ash auger transfer system continuously removed
kiln ash from the hopper and deposited it into clean 55-gallon
drums.
After completing flue gas sampling for each test, test material
feed was stopped. The incinerator was then continually fired with
natural gas for two hours or until the kiln was visibly clear of
ash material, whichever time period was longer. Ash collected
from each test's ash drum was weighed and sampled. Scrubber
liquor samples were collected from a tap in the recirculation
loop before the scrubber liquor loop was drained. The contents
of the baghouse hopper (collected fly ash) were emptied into a
collection bucket and transferred to a sample container. The en-
tire amount collected was used as the baghouse ash sample. After
the scrubber liquor loop was recharged with fresh makeup wa-
ter, the incinerator was either turned off (during weekends) or
operated overnight by firing natural gas to produce steady-state
conditions for the next test.
For all tests, the incinerator operating parameters noted in Table
11 were recorded at intervals of no longer than 15 minutes. Table
12 summarizes the average operating conditions achieved for
the various components of the RKS for each of the 12 tests. Test
Conditions 1 and 2 were without the Sonotech system in opera-
tion. The subsections below discuss the pulse combustion system,
operating parameters, and system maintenance.
Tests 1 through 12 were performed in chronological order.
Tests 1,2,3, and 4 were the first tests at Test Conditions 1,2,3,
and 4, respectively. The split of auxiliary fuel feedrates between
the kiln and the afterburner was not exactly as desired during
Test 3. Specifically, the total auxiliary fuel feedrate to the kiln,
at 388 kBtu/hr for Test 3, was lower than the 494 kBtu/hr for
Test 2, and the auxiliary fuel feedrate to the afterburner, at
1,200 kBtu/hr, was greater than the 1,060 kBtu/hr for Test 2. The
auxiliary fuel distributions for Test 5, the second Test Condi-
tion 3 test, with a total kiln feedrate of 494 kBtu/hr and an
afterburner feedrate of 1,020 kBtu/hr, were more nearly those
for Test 2. Thus, Test 5 was chosen to represent Test Condition 3.
Because these were the first tests at each respective test condi-
tion tested, the feedrate and other incinerator operating conditions
for these tests were used as targets for subsequent tests at each
respective condition.
Test 1 was performed atawaste feedrate of 61.6 Ib/hr, achieved
by charging a waste container to the kiln every 11 minutes. An
additional 635 kBtu/hr of auxiliary fuel was needed in the kiln
to maintain the desired kiln exit gas temperature of nominally
1,700°F (927°C). Average afterburner exit CO levels were an
acceptable 9 ppm corrected to 7% oxygen. Over the duration of
this test, four CO spikes of 100 ppm or greater occurred, corre-
sponding to an average of a spike every fourth charge. Of the
four spikes experienced, the largest peaked at about 540 ppm,
one peaked at about 370 ppm, and two peaked at about 100 ppm.
For Test 2, the waste feed charge frequency was increased to
one charge every 9 minutes, giving an increased waste feedrate
of 72.3 Ib/hr. Because the waste had considerable heating value,
less auxiliary fuel was required to maintain the target kiln exit
gas temperature. Thus, the auxiliary fuel feedrate to the kiln was
decreased to the minimum allowable, at 494 kBtu/hr (nominally
500 kBtu/hr). Average afterburner exit gas CO was significantly
increased 40 ppm, corrected to 7% oxygen. A higher waste
feedrate for this condition, by increasing charge frequency to
one charge every 8 minutes, was not possible because kiln exit
gas temperature would have increased to well above the desired
target. Temperature control by decreasing auxiliary fuel feedrate
was not possible as this was already at the allowed minimum. It
was decided that feedrate changes of less than about 10%, cor-
responding to feed charge frequency changes of integral minutes,
would not be considered significant. Over the duration of flue
gas sampling for Test 2, nine CO spikes of over 100 ppm oc-
curred, corresponding to an average of a spike every two to three
charges. Of these nine, six drove the CO monitor to its full-scale
reading of 630 ppm, one peaked at about 550 ppm, one at about
Table 10. IRF RKS Air Pollution Control System Operating
Parameters
Venturi liquor flowrate
Venturi pressure drop
Packed tower liquor flowrate
Scrubber liquor temperature
Scrubber blowdown rate
20 gallons per minute (gpm)
(76 liter per minute [L/min])
25 inches of water (6.2
kilopascal [kPa])
30 gpm (115 L/min)
120°F(49°C)
0 gpm (0 L/min) or minimum
operable rate
Notes: L/min = Liter per minute
kPa = Kilopascal
gpm = Gallon per minute
30
-------
Table 11. Measured Incinerator Operating Parameters
Temperature
Rotary kiln exit gas
Rotary kiln solids at 4 axial locations
Afterburner exit gas
Quench inlet gas
Quench exit gas
Scrubber exit gas
Baghouse exit gas
Stack gas
Recirculating quench/scrubber liquor
Scrubber blowdown liquor
Flowrates
Rotary kiln main burner natural gas feed
Sonotech burner natural gas feed
Afterburner natural gas feed
Rotary kiln main burner combustion air
Sonotech burner combustion air
Afterburner combustion air
Stack combustion gas
Venturi scrubber liquor
Packed tower scrubber liquor
Scrubber blowdown liquor
Scrubber makeup liquor
Pressures
Rotary kiln chamber
Afterburner chamber
Venturi scrubber pressure drop
Packed tower scrubber pressure drop
Baghouse pressure drop
Other
Scrubber liquor pH
Cumulative test material weight fed
220 ppm, and one at about 150 ppm. As noted above, the aver-
age CO level over the duration of flue gas sampling was 40 ppm,
corrected to 7% oxygen. Increasing waste feedrate by increas-
ing feed charge frequency to one charge every 8 minutes would
also have increased the frequency of CO spikes and, in turn the
average CO level. At 40 ppm, corrected to 7% oxygen, the aver-
age CO was near the defined test operational limit of 50 ppm,
corrected to 7% oxygen. In summary, the waste feedrate for Test
2 was indeed the maximum that could be achieved under con-
ventional combustion. Based on many years of testing experience
at the IRF, operator judgement was that further increases in
feedrate beyond that achieved would have resulted in a signifi-
cantly increased kiln exit gas temperature and a much increased
frequency of CO spikes in the afterburner exit gas, possibly giv-
ing rise to average afterburner exit gas CO levels above the
50-ppm operational limit.
For Test 5, representing Test Condition 3 (with the Sonotech
system operating), the waste feed charge frequency was held at
one charge every 9 minutes, giving a waste feedrate of 74 Ib/hr,
essentially the same as for Test 2 at Test Condition 2, as desired.
Kiln exit gas temperature remained at nominally 1,700°F
(927°C), with auxiliary fuel feedrate to the kiln (now apportioned
between the Sonotech burner and the kiln main burner) remain-
ing at nominally 500 kB tu/hr. Over the duration of flue gas sam-
pling for Test 5, eight CO spikes over 100 ppm occurred,
corresponding to an average, again, of a spike every two to three
charges. Of the eight spikes, two were at the instrument full-
scale of 630 ppm, one peaked at about 220 ppm, two at about
180 ppm, and one at about 150 ppm. Thus, while the frequency
of CO spikes for Test Condition 3 was nearly the same as for
Test Condition 2, average peak levels were lower for Test Con-
dition 3. Accordingly, the average CO for Test 5 was lower, at
16 ppm, corrected to 7% oxygen.
For Test 4, representing Test Condition 4 (with the Sonotech
system operating), the waste feed charge frequency was further
increased to one charge every 8 minutes, giving an increased
feedrate for this test of 83.8 Ib/hr. Because the IRF operations
staff had very limited experience with the Sonotech system, no
prior experience base was available to guide expectations re-
garding the incinerator's response to increasing waste feedrate
above the maximum achievable under conventional combustion.
Upon increasing waste feedrate, the kiln exit gas temperatures
remained at the target of about 1,700°F (927°C), with kiln aux-
iliary fuel flow, while slightly decreased, still at nominally
500 kB tu/hr. This increased waste feedrate, while maintaining
kiln temperatures, using nominally the same minimum auxiliary
fuel feed to the kiln, was only possible by having the Sonotech
system in operation. Over the duration of flue gas sampling for
Test 4, eight CO spikes over 100 ppm occurred, corresponding
to a spike every third charge. Of the eight spikes, three were at
the instrument full-scale level of 630 ppm, and one each peaked
at about 420, 380, 300, 260, and 220 ppm. The corresponding
average afterburner exit gas CO was 17 ppm, corrected to 7%
oxygen. Thus, in comparison to Test 2, an increased waste
feedrate could be maintained, at more acceptable afterburner exit
gas CO levels, only by employing the Sonotech burner system.
4.3.1.1 Sonotech Cello® Pulse Combustion
System
The general principles of pulse combustion and the Sonotech
pulse combustion technology are described in Section 1.4. The
pulse combustor used in this test program was fabricated to meet
the needs of the IRF RKS. The combustor was approximately 6
feet (1.8 meters) long and4 feet (1.2 meters) wide and was sup-
ported by a structure designed to align its axis into the available
port in the incinerator. The pulse combustor was also fitted with
a flanged plate that enabled it to be attached to the incinerator.
The unit consisted of a tunable pulse combustor, fuel and air
trains with flow meters, and a control system. The combustor
was designed to deliver approximately 250,000 Btu/hr (74 kW)
to the kiln.
4.3.1.2 Operating Parameters
The tests were configured so that the Sonotech pulse combus-
tor would deliver a heat input of roughly 15% to 20% of the
typical heat input to the kiln. Exploratory tests revealed that a
resonance was achieved in the kiln chamber when the pulse com-
bustor was operated at 300 ± 20 Hertz (Hz). Based on results of
the exploratory tests, the nominal settings for all tests with the
pulse combustor operating were as follows: natural-gas flow rate
of 200 standard cubic feet per hour (5.7 standard cubic meters
31
-------
Table 12. Operating Data and Results
Test Condition (Average Values)
Parameter
1: Conventional
Combustion
Baseline
Feedrate
2: Conventional
Combustion
Maximum
Feedrate
3: Pulse
Combustion
Baseline
Feedrate
4: Pulse
Combustion
Maximum
Feedrate
Waste foooYate. IWhr 61.0
Waste heating value, Btu/lb 8.750
Rotary kiln exit gas temperature, °F 1,720
AltQfburnor exit gas temperature, °F 2,000
Heat input, kBtutir
Waste feed 522
Kiln auxiliary fuel
Main burner 659
Sonotoch burner 0
Total kiln 659
Afterburner auxiliary fuel 1,010
Total auxiliary fuel 1,670
Total system heat input, kBlu/hr 2,190
Kiln ash heating value, Btu/lb 1,240
Combustion air, dscf/hr 41,700
Afterburner exit CO, ppm at 7% O., 15
Afterburner exit NOX, ppm at 7% O2 90
Afterburner soot emission rate,
mg/dscm at 7% Oz <1.3
(TOC as percent of paniculate)
72.8
8,750
1,730
2,000
601
506
0
506
1,040
1,540
2,150
1,320
39,500
20
82
1.9
73.6
8,750
1,700
2,000
628
282
200
482
1,094
1,580
2,200
<500
37,500
14
77
82.4
8,750
1,700
2,000
697
205
200
405
1,082
1,480
2,180
1,430
38,400
18
78
1.3
No'.os: Each value (except condition 1 afterburner exit soot emissions) is the average of results for three test runs.
fo/hr
Blu/!b
kBtu/hr
dscl/hr
ppm
mg/dscm
CO
NO
Pounds per hour
British thermal units per pound
Thousand British thermal units per hour
Dry standard cubic feet per hour
Parts per million
Milligram per dry standard cubic meter
Carbon monoxide
Nitrogen oxide
Oxygen
Total organic carbon
per hour), air flow rate of 2,000 standard cubic feet per hour (57
standard cubic meters per hour), and a pulsation frequency of
300 Hz.
4.3.1.3 System Maintenance
Scoping and demonstration test runs were performed at the
IRF from May through October 1994. During this time, the
Sonotech pulse combustion system experienced no operational
problems. Routine maintenance during this period involved only
visual inspection of Uie burner system prior to start-up. No other
special maintenance was required.
4.3.2 Results and Discussion
As noted in Section 4.2.3, composite feed material samples
were not collected and analyzed for each test. Instead, samples
of each feed component were collected for analysis. Thus, the
composition of the test program feed material was defined based
on measured component composition and component propor-
tions in the integrated feed. Table 13 summarizes the feed
component VOC and S VOC concentrations measured. Table 14
lists the metal concentrations in the various feed materials.
4.3.2.1 Primary Objective
The primary objective of the demonstration was to develop
test data to evaluate the treatment efficiency of the Sonotech
system compared to conventional combustion. Test data were
evaluated to determine if the Sonotech system accomplished the
following developer claims:
(1) Increased incinerator capacity
(2) Increased the DRE of POHCs
32
-------
Table 13. Concentrations of Volatile and Semivolatile Organic
Constituents in Feed Materials
Concentration (mg/kg)
Volatile
Constituent
Benzene
Ethylbenzene
Toluene
Total xylenes
Acenaphthene
Acenaphthylene
Anthracene
Benz(a)anthracene
Benzo(g,h,i)perylene
Benzo(a)pyrene
Chrysene
Fluoranthene
Fluorene
lndeno(1 ,2,3-cd)pyrene
2-Methylnaphthalene
Napthalene
Phenanthrene
Pyrene
Soil
0.3
0.3
0.1
0.5
150
60
130
90
40
90
100
190
120
30
170
130
340
250
Spike8 Composite
750,000 9,040
1,300
510
410
690
3,250
2,390
1,470
6,300
1,280
1,750
2,910
1,810
480
7,070
250,000 13,500
7,470
4,100
Notes:
a = Only benzene and naphthalene were spiked
mg/kg = Milligrams per kilogram
(3) Decreased flue gas CO emissions
(4) Decreased flue gas NOx emissions
(5) Decreased flue gas soot emissions
(6) Decreased combustion air requirements
(7) Decreased auxiliary fuel requirements
Test data addressing items (1), (6), and (7) are presented in
Table 12. Data in this table represent the average of three tests at
each test condition. Data show that the kiln exit gas temperature
tested for all conditions averaged close to the test program tar-
get of 1,700°F (927°C) and that average afterburner exit gas
temperature was right at the test program target of 2,000°F
(1,090°C).
For Test Condition 1, the target waste feedrate was 61.1 Ib/hr
(27.8 kg/hr). This feedrate was increased to a target of 74.7 Ib/hr
(33.9 kg/hr) to give the borderline acceptable operation associ-
ated with Test Condition 2. Test Condition 3, with the pulse
combustion system in operation, was targeted at the same feedrate
as Test Condition 2, and the Test Condition 3 feedrate was 21%
greater than the Test Condition 1 feedrate. An additional 13%
increase in feedrate over the feedrate used in Test Condition 2
was possible before incinerator operation entered the borderline
acceptable range with the pulse combustion system in opera-
tion. This resulted in a target feedrate of 84.0 Ib/hr [38.2 kg/hr]
for Test Condition 4. These test data show that a capacity in-
crease of at least 13% (comparing Test Condition 4 to Test
Condition 2) can be realized. In addition, the feedrate for Test
Condition 4 was 35% greater than that for Test Condition 1.
Data in Table 12 further show that the total system heat input
needed to maintain target incineration temperatures was rela-
tively constant for all four test conditions at about 2.2 million
Btu/hr (645 kW).
In addition, the auxiliary fuel requirements for Test Condi-
tions 2 and 3 were nominally the same. Because auxiliary fuel
use was relatively constant, the test data do not support the
Sonotech claim that decreased auxiliary fuel use would be pos-
sible with the application of pulse combustion. However, because
the waste treated in these tests had significant heat content, the
capacity increase noted above equates to a corresponding de-
crease in the auxiliary fuel consumed per unit of waste treated.
Comparing the auxiliary fuel consumption per unit of waste
treated for Test Conditions 4 and 2 indicates that the feedrate
increase allowed by the Sonotech system yields a correspond-
ing decrease in auxiliary fuel use per unit of waste treated from
21,100 Btu/lb (52.5 megajoules per kilogram [MJ/kg]) to
18,000 Btu/lb (42.5 MJ/kg). Visual observations indicated that
the Sonotech system produced improved mixing in the kiln cham-
ber.
Data in Table 12 show that less combustion air was required
for the two pulse combustion test conditions compared to con-
ventional combustion test conditions. As the table shows, the
combustion air requirements for Test Conditions 3 and 4 were
lower than those for Test Conditions 1 and 2.
Test data addressing items (3), (4), and (5) are shown in Table
15. CEM data in this table represent the average of three tests at
each test condition. Soot emission data represent the average for
three tests at each test condition.
Data in Table 15 show that average kiln exit CO levels sub-
stantially increased with pulse combustion, from 68 ppm for the
two conventional combustion test conditions (1 and 2) to 117 ppm
for Test Condition 3 and 153 ppm for Test Condition 4. This in-
crease is consistent with the observations that pulse combustion
caused increased kiln solids bed temperatures and decreased kiln
ash residue quality (heating value) when comparing Test Condi-
tion 3 to Test Condition 2. These findings, also discussed in
Appendix Case Study 4, suggest that pulse combustion caused a
greater degree of waste feed organic content volatilization into
the kiln combustion gas. The observation that kiln exit CO lev-
els increased with pulse combustion suggests that the greater
amounts of volatilized organics were not completely destroyed
in the kiln.
33
-------
Tsblo 14. Concentrations of Metals In Feed Materials
Avoraga
Concontrations
Tar, mg/kg
SoH, mg/kg
Coal/Studgo, mg/kg
Composite food, mg/kg
TarTCLP, mg/L
SoH TCLP, mg/L
Coat/SludgoTCLP, mg/L
Antimony
<20
<20
<20
<19
<0.03
<0.03
0.08
Barium
<1
<30.6
658
<271
0.45
0.84
0.56
Beryllium
<0.03
0.93
1.17
<0.8
<0.0003
<0.0005
<0.0003
Chromium
<0.7
33
26.4
<21
<0.007
<0.007
<0.007
Cadmium
<0.5
0.75
0.8
<0.7
<0.004
<0.004
<0.004
Mercury
<1.6
1.6
<1.6
<1.5
<0.0002
<0.0002
<0.0002
Lead
<10
27.4
36.4
<25.3
<0.38
<0.07
<0.04
Notes:
mg/kg » Milligrams per kilogram
mg/L = Milligrams per liter
TCLP * Toxicity characteristic leaching procedure
Incineration system afterburners are specifically designed to
complete the combustion process and destroy products of in-
complete combustion (such as CO) in the kiln exit combustion
gas. During the demonstration, average afterburner exit CO lev-
els decreased to 15 ppm for Test Condition 1 and to 20 ppm for
Test Condition 2. Compared to conventional combustion, pulse
combustion produced slightly lower average afterburner CO lev-
els. Test Condition 2 (with conventional combustion) and Test
Condition 3 (with pulse combustion) both had the same nominal
waste fccdrate, indicating that pulse combustion decreased av-
erage afterburner exit CO emissions to 14 ppm. Even at the
increased waste fcedrate achieved with pulse combustion for Test
Condition 4, afterburner exit CO levels were only marginally
increased to 17 ppm, which is higher than the Test Condition 3
level but is still 15% lower than the Test Condition 2 level.
CO is the final incomplete combustion product in the series of
reactions that converts the carbon in organic constituents to CO2.
One explanation for the lower afterburner exit CO levels under
pulse combustion operation (compared to conventional combus-
tion), while kiln exit levels were higher, may be that organic
constituent combustion in the kiln was more complete underpulse
combustion operation. More complete combustion of organic
constituents can result in higher CO levels (the final incomplete
combustion product), while other unburned hydrocarbon levels
(including soot) would be decreased. In such cases, fewer in-
complete combustion products enter the afterburner, reducing
the afterburner's burden to complete the destruction process. This
can result in lower afterburner exit CO levels.
The afterburner exit soot emissions data (measured as TOC in
the afterburner exit paniculate) show a consistent pattern in the
demonstration tests. Soot emission levels given in Table 15 rep-
resent the average for each of three tests at each condition, with
the exception of the level noted for Test Condition 1. The after-
burner exit particulate was analyzed for TOC for only one Test
Condition 1 test, so the Test-Condition 1 value in Table 15 re-
flects only the one measurement. Soot emission levels were less
than 1.3 mg/dscm for Test Condition 1, the baseline, conven-
tional combustion test condition. They were increased to
1.9 mg/dscm for Test Condition 2. However, for Test Condi-
tion 3, with pulse combustion at the same feedrate as Test
Condition 2, soot emissions decreased to less than 1.0 mg/dscm.
Even at the increased waste feedrate achieved for Test Condi-
tion 4, the afterburner exit soot emissions were 1.3 mg/dscm,
which is less than that of Test Condition 2. Average baghouse
exit particulate emissions, corrected to 7% oxygen , were 133,
124,64, and 104 mg/dscm for Test Conditions 1 through 4, re-
spectively.
Table 16 shows that afterburner exit and baghouse exit NOx
emissions were comparable from test condition to test condi-
tion.
Although the data confirm the Sonotech claim that pulse com-
bustion decreases NOx emissions, the reductions achieved were
small and originated from low initial NOx levels.
DRE test data for benzene and naphthalene, the two test pro-
gram POHCs, are given in Table 17. POHC feedrate values shown
in the table result from combining the test waste feedrate mea-
sured for each test (see Table 12) with the waste feed POHC
concentration (see Table 13). The POHC emission rate values
noted in Table 17 were determined by combining flue gas flow
rate data at each sample location for each test with the flue gas
POHC concentration measured by the respective flue gas sam-
pling procedure.
Naphthalene DREs measured at both the afterburner exit and
the baghouse exit were uniformly 99.999% or greater for all tests
and were not affected by different test conditions or different
waste feedrates. Benzene DREs measured at the two locations
also were not affected by different test conditions and were typi-
cally 99.994% or greater (with one baghouse exit benzene DRE
measurement was 99.989%).
The average naphthalene emission rate at the afterburner exit
was reduced from 1.2 mg/hr for conventional combustion at Test
Condition 2 to 1.1 mg/hr with the Sonotech system at Test Con-
dition 3. The average benzene emission rate at the afterburner
exit was reduced from 7.7 mg/hr for Test Condition 2 to 5.7 mg/hr
34
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Table 15. Summary of Gaseous Emissions Data
Test Condition 1 2
Kiln Exit
02, %
CO, ppm
CO @ 7% O2, ppm
Afterburner Exit
O2> %
CO, ppm
CO @ 7% O2, ppm
C02> %
TUHC, ppm
TUHC @ 7% O2, ppm
Baghouse Exit
O2, %
C02, %
Stack
02, %
CO, ppm
CO @ 7% O2, ppm
Soot
TOC %
Emission rate mg/hr
@ 7% O2 mg/hr
11.3
47.1
67.9
9.3
12.8
15.2
7.8
1.0
1.2
11.2
6.1
12.2
6.5
10.4
<1.0a
<1,200a
<1.3a
11.1
48.3
68.0
9.3
16.2
20.3
8.0
1.5
1.8
10.8
6.5
11.9
13.9
21.3
1.6
1966
1.9
10.5
87.7
117.1
8.7
12.7
14.4
8.4
1.22
1.4
10.7
6.4
11.8
12.3
25.6
<1.0
96
0.9
10.7
111.1
153.4
8.5
16.0
17.9
8.6
1.6
1.8
10.6
6.7
11.8
12.5
19.0
1.4
1,466
1.3
Notes:
"Indicates result of one analysis as two samples were lost
ppm = Parts per million
Table 16. Nitrogen Oxides Emissions
Test
Condition
1
2
3
4
Afterburner Exit
NOX Emissions
90 ppm
82 ppm
77 ppm
78 ppm
Baghouse Exit
NOX Emissions
88 ppm
85 ppm
78 ppm
72 ppm
Note: All values corrected to 7% oxygen
ppm = Parts per million
for Test Condition 3. The significance of these decreases is dif-
ficult to judge because both fall within the precision of the
respective flue gas concentration measurement methods.
4.3.2.2 Secondary Objective
The demonstration's secondary objective was to develop ad-
ditional data to evaluate whether the Sonotech system, compared
to conventional combustion, (1) reduced the magnitude of tran-
sient puffs of CO and TUHC; (2) resulted in reduced incinera-
tion costs; (3) significantly changed the distribution of hazardous
constituent trace metals in the incineration system discharge
streams (including kiln bottom ash, scrubber liquor, andbaghouse
exit flue gas); and (4) significantly changed the leachability of
the TCLP trace metals from kiln ash. Data developed in support
of the secondary objective reveal the following:
• Test program CEM data indicate that the Sonotech system
did not change the magnitude of transient puffs of CO and
TUHC, with no increases or decreases.
• Section 3 of this document discusses potential cost savings
associated with use of the Sonotech system.
• Table 18 summarizes trace metal distribution data from the
demonstration test program. The data suggest that using the
Sonotech system does not affect the distribution of beryl-
lium, cadmium, or lead. The concentration of barium and
chromium appear to be slightly decreased in scrubber li-
quor and measurably increased in the baghouse exit flue
gas for the Sonotech system test runs.
• Table 19 summarizes trace metal concentration data in the
TCLP leachates of incinerator feed in residual discharges.
The data show that the test program waste feed, the kiln
ash, and the scrubber liquor residual, for all test conditions,
are not RCRA toxicity characteristic hazardous wastes. In
addition, TCLP leachate trace metal concentrations were not
affected by using the Sonotech system.
4.3.2.3 Other Emissions Data
This section discusses other emissions data collected during
the demonstration.
VOC and S VOC Data
Kiln ash and scrubber liquor samples for each test were ana-
lyzed for the VOCs and SVOCs listed in Table 6. No VOC or
SVOC constituent was detected in any kiln ash or scrubber li-
quor sample from any test, with the exception of benzene in a
few cases. Detection limits for VOCs were 1 to 10 mg/kg in kiln
ash, and 1 to 10 microgram per liter (p.g/L) in scrubber liquor.
Detection limits for SVOCs were 0.1 to 0.3 mg/kg in kiln ash,
and 1 to 3 |j.g/L in scrubber liquor. Benzene was detected in the
kiln ash samples from one Test Condition 2 test, from one Test
Condition 3 test, and from all three Test Condition 4 tests; how-
ever, these levels were only slightly above the MDLof 1 mg/kg.
Dioxin and Furan Data
The IRF RKS baghouse exit flue gas was sampled for PCDD
and PCDF emissions during all 12 test runs. Although various
PCDD and PCDF congeners containing chlorine atoms at the 2,
3, 7, and 8 positions were detected during each test run, no
2,3,7,8-tetrachlorodibenzo-para-dioxin (2,3,7,8-TCDD) conge-
ner was detected. The detection limit for 2,3,7,8-TCDD, which
is sample specific for this analysis, ranged from 2.37 to 7.56
picograms per sample.
The total PCDD and PCDF emission values for each test con-
dition were calculated based on the 2,3,7,8-TCDD toxicity
35
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Table 17. Summary of Test Program POHC DREs
co
05
Notes:
Benzene
Naphthalene
Condition 1
Testl
Tests
Test 10
Condition 2
Test2
Test?
Test 11
Condition 3
Tests
' Test 5
Test9
Condition 4
Test 4
Tests
Test 12
Feed Rate
(mg/hr)
253,000
253,000
244,000
298,500
307,500
289,500
289,500
307,500
307,500
343,500
334,500
334,500
Afterburner Exit
Emission Rate'
(mg/hr)
4.4
7.6
14.8
9.0
2.1
12.0
6.9
3.4
6.7
10.4
11.7
50.9
Baghouse Exit
ORE
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
Emission Rate'
(mg/hr)
<1.2
2.1
3.4
31.0
<0.9
0.6
6.4
1.5
2.9
2.5
<1.5
1.1
ORE
>99.99
>99.99
>99.99
>99.98
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
Feed Rate
(mg/hr)
378,000
378,000
364,500
445,500
459,000
432,000
432,000
459,000
459,000
513,000
499,500
499,500
Afterburner Exit
Emission Rate
(mg/hr)
6.2
2.9"
<0.3
2.6"
0.6"
0.4"
2.5"
<0.3
0.5"
0.6"
0.5"
1.3"
Baghouse Exit
ORE
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
Emission Rate
(mg/hr)
5.9
3.1"
2.5"
6.0
<0.3
3.5b
2.4"
0.6"
1.6"
1.4"
2.2"
0.4"
ORE
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
>99.99
'Average concentration of three pairs of M0030 VOST tubes
bAnalyte detected below lowest calibrated level
> = Greater than indicated ORE
< = Analyte below method detection limit
ORE = Destruction and removal efficiency
mg/hr = Milligrams per hour
-------
Table 18. Metals Distribution Results
Average Concentrations
Barium
Berylium
Chromium
Cadmium
Lead
Kiln ash (mg/kg)
Condition 1 70.0
Condition 2 85.0
Condition 3 60.0
Condition 4 63.0
MDL 1
Scrubber liquor (Post-test) (ug/L)
Condition 1 500
Condition 2 800
Condition 3 360
Condition 4 457
MDL 2
Scrubber exit flue gas (u,g/dscm)
Condition 1 30
Condition 2 20
Condition 3 1 02
Condition 4 1 03
MDL 0.8
Composite feed (mg/kg) <271.0
MDL 1
Notes: Antimony and mercury were not detected in any samples
< = Average value is below MDL
mg/kg = Milligrams per kilogram
MDL = Method detection limit
Hg/dscm = Microgram per dry standard cubic meter
u,g/L = Micrograms per liter
1.5
1.3
1.4
1.3
0.03
4
7
6
3
0.3
<0.1
<0.1
<0.3
<0.3
0.1
<0.8
0.003
56.0
33.0
37.0
39.0
0.7
60
300
109
58
0.1
7.0
7.0
34.0
34.0
2.4
<21.0
0.7
<0.6
<0.7
<0.5
<0.5
0.5
2
3
7
17
7
<1.0
<1.0
<1.0
<1.0
1.0
<0.7
20.5
<16.5
17.0
<12.5
<10.0
10.0
1123
1590
800
2110
1
<11.0
<11.0
<12.0
<11.0
10.0
<25.3
10
Table 19. TCLP Results of Feed, Ash, and Scrubber Liquor
Barium Beryllium
Notes:
mg/L = Milligrams per liter
NR = Not TCLP regulated
< = Average value is below MDL
Chromium
Cadmium
Lead
Feed, mg/L
Coal
Soil
Ash, mg/L
Condition 1
Condition 2
Condition 3
Condition 4
Scrubber liquor, mg/L
Condition 1
Condition 2
Condition 3
Condition 4
Regulatory level (mg/L)
0.56
0.84
0.30
0.62
0.50
0.69
0.15
0.20
0.13
0.13
100
<0.0003
<0.0005
<0.0003
<0.0003
<0.0003
<0.0003
<0.0005
<0.0003
<0.0003
<0.0003
NR
<0.007
<0.007
• <0.007
<0.007
<0.007
<0.007
0.03
0.03
0.08
<0.03
5
<0.004
<0.004
<0.004
<0.004
<0.004
<0.004
<0.006
<0.005
<0.004
<0.012
1
<0.04
<0.07
<0.04—
<0.04
<0.05
<0.06
0.7
0.3
0.4
0.9
5
37
-------
equivalency factors (TEF). The total emissions, based on the
TEFs, are referred to as 2,3,7,8-TCDD equivalents (TEQ) and
were calculated by two methods as various analytes were re-
ported as "undetected." First, the nondetected analyte
concentration was assigned the MDL, and, second, the analyte
was assigned a value of zero. This calculation method brackets
the true TEQ value. All calculated concentrations were also cor-
rected to 7% oxygen. The TEQ values for all runs were very low
with no clear distinctions noticed with the Sonotech system op-
crating. Table 20 presents the PCDD and PCDF TEQ values.
Table 20. Average DIoxin and Furan Toxicity Equivalent Emissions
(plcograms/dscm)
2,3,7,8-TCDD TEQ Value
Test Condition
MDL
Zero
1
2
3
4
5.4
5.0
4.1
4.6
0.4
0.4
0.3
0.6
Notes:
dscm » Dry standard cubic meter
TEQ - Toxicity equivalency emission
MDL • TEQ calculated by assigning all nondetected PCDD
and PCDF congeners the value of their respective
detection limit
Zero - TEQ calculated by assigning all nondetected PCDD
and PCDF congeners a value of zero
Particulate and Hydrogen Chloride Data
The 1RF RKS stack was sampled to measure particulate and
hydrogen chloride emissions for all 12 tests. These measure-
ments were necessary to address the IRF operating permit
requirements and were performed after the RKS state-of-the-art
emission control system. The stack particulate emissions for the
12 tests ranged from less that 0.5 to 2 mg/dscm, corrected to 7%
oxygen. These values were considerably below the maximum
permitted 180 mg/dscm. There were no distinct variations in par-
ticulate loading between the different test conditions.
Chloride ion was not detected in any of the Method 5 sam-
pling trains. The MDL for hydrogen chloride emissions for each
test, when corrected to 7% oxygen, was equal to or less than
0.24 g/Iir, considerably less than the IRF permitted level of 500
g/hr.
Ash Quality Data
Kiln ash quality, measured as the kiln ash heating value, is
presented in Table 12. With the Sonotech system operating un-
der optimal test conditions (Test Condition 3), the heating value
of the residual kiln ash was below detection limits.
4.3.3 Data Quality
The overall project QA objective was to produce well-docu-
mented sampling and analytical data that are reproducible and
defensible. This objective was met by establishing precision,
accuracy, method target reporting limit (TRL), completeness,
and comparability goals. Data were evaluated with respect to
these project goals. During the demonstration, the field team
collected QA/QC samples—including matrix spike and matrix
spike duplicate (MS/MSD) samples, field blanks, trip blanks,
and equipment blanks. Laboratory QC samples were also ana-
lyzed to assure that data quality and proper procedures were used.
Data quality indicators were calculated in accordance with es-
tablished equations. Representativeness was assessed by
evaluating the relative percent difference (RPD) values calcu-
lated from the duplicate samples and by evaluating the
concentrations of interferences detected in the field and labora-
tory QC blanks. Based on an evaluation of these factors, the
samples collected are considered representative of the media
sampled.
QC checks and procedures were an integral part of the
Sonotech demonstration to ensure that the QA objectives were
met. QC checks and procedures focused on (1) the collection of
representative samples without external contamination, and
(2) the analysis of comparable data. Three kinds of QC checks
and procedures were conducted during the demonstration:
(1) checks controlling field activities, such as sample collection
and shipping; (2) QC procedures associated with the field mea-
surements; and (3) checks controlling laboratory activities, such
as extraction and analysis. After a review of the QC results, 100%
of the data from this demonstration is useable.
4.3.4 Conclusions
To achieve the demonstration objectives, tests were performed
in triplicate at four different incineration system operating con-
ditions, for a total of 12 individual tests. The four test conditions
included the following:
• Test Condition 1, conventional combustion at typical oper-
ating conditions
• Test Condition 2, conventional combustion at its maximum
feedrate
• Test Condition 3, Sonotech pulse combustion at the maxi-
mum feedrate for conventional combustion (the same
nominal feedrate as Test Condition 2)
• Test Condition 4, Sonotech pulse combustion at its maxi-
mum feedrate
Data collected during the Sonotech SITE demonstration were
evaluated using the rank sum test. The rank sum test allows the
user to assess whether observed differences in data sets are sta-
tistically significant. When comparing two data sets, each
containing three data points, the two data sets are different at the
95% confidence level when there is no data overlap. Unless noted,
all conclusions are based on comparison of the average results
from Test Condition 3 to the average results from Test Condi-
tion 2. The following conclusions may be drawn about the
benefits of the Sonotech system:
• The Sonotech system increased the incinerator waste
feedrate capacity by 13% compared to conventional com-
bustion when comparing Test Condition 4 to Test Condition
2. The capacity increase was equivalent to reducing the aux-
iliary fuel needed to treat a unit mass of waste from an
average of 21,100 Btu/lb (range of 21,000 to 21,300) for
38
-------
conventional combustion to 18,000 Btu/lb (range of 16,600
to 19,000) for the Sonotech system. Visual observations in-
dicated improved mixing in the incinerator cavity when the
Sonotech system was operating.
• Benzene DREs for all 12 test runs were greater than
99.994%. The Sonotech system reduced the average ben-
zene emission rate from 7.7 mg/hr (range of 2.1 to 12) to
5.7 mg/hr (range of 3.4 to 6.9) at the afterburner exit.
• Naphthalene DREs were greater than or equal to 99.998%
for all test runs. The Sonotech system reduced the average
naphthalene emission rate from 1.2 mg/hr (range of less than
0.3 to 6.2) to 1.1 mg/hr (range of less than 0.3 to 2.5) at the
afterburner exit.
Other demonstration results, comparing test conditions with
the same nominal feedrate, are summarized as follows:
• The average afterburner CO emissions, corrected to 7%
oxygen, decreased from 20 ppm (range of 8.0 to 40.0) with
conventional combustion to 14 ppm (range of 12.6 to 16.0)
with the Sonotech system.
• The average afterburner NOx emissions, corrected to 7%
oxygen, decreased from 82xppm (range of 78.3 to 85.1)
with conventional combustion to 77 ppm (range of 68.0 to
87.1) with the Sonotech system.
• Average afterburner soot emissions, measured as TOC and
corrected to 7% oxygen, were reduced from 1.9 mg/dscm
(range of less than 0.9 to 2.7) for conventional combustion
to less than 1.0 mg/dscm (range of less than 0.8 to 0.9) with
the Sonotech system.
• Total system combustion air requirements, determined from
stoichiometric calculations, were lower with the Sonotech
system in operation. The ranges for these values were 38,400
to 40,600 dscf/hr without the Sonotech system and 34,800
to 39,900 dscf/hr with the Sonotech system operating.
• Total natural gas fuel requirements (including kiln and af-
terburner) for all test conditions were similar. The total
system average natural gas usage was 1,540 dscf/hr (range
of 1,480 to 1,590) for conventional combustion and
1,580 dscf/hr (range of 1,520 to 1,620) for the Sonotech
system at approximately the same feedrate.
Other general findings include:
• No substantial increase or decrease occurred in the frequency
or magnitude of transient CO or TUHC puffs with the
Sonotech system operating.
• Under the demonstration test conditions, use of the Sonotech
system with the reported increase in incineration capacity
can result in a cost savings. The reader is referred to the
Economics section of this report to determine the approxi-
mate cost savings for a specific application.
• During the Sonotech demonstration, the Cello® combus-
tion system caused no downtime and was judged to be
reliable.
• Target metals investigated included antimony, barium, be-
ryllium, cadmium, chromium, lead, and mercury. Their
distribution in the discharge streams of the RKS did not
vary significantly from test to test or from test condition to
test condition except for barium and chromium. Concentra-
tions of these two metals were slightly lower in the scrubber
liquor and measurably higher in the baghouse exit flue gas
when the Sonotech system was operating.
• The concentrations of target metals in the TCLP leachates
were low to not detected in the feed, kiln ash, and scrubber
liquor. At these concentrations, no significant test-to-test
variations in the TCLP leachability of the various discharge
streams were observed.
• No VOC or SVOC, other than benzene, were detected in
any kiln ash or scrubber liquor samples.
• Dioxin toxicity equivalent values for all runs were very low
and no clear distinctions were noticed with the Sonotech
system operating.
• Stack paniculate and hydrogen chloride emissions were very
low with no distinct variations between different test condi-
tions.
39
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Section 5.0
Technology Status
5.1 Introduction
The Sonolcch patented pulse combustion system has been
developed to improve the performance of energy-intensive in-
cineration and combustion processes. The primary component
of the Sonotech system is the frequency-tunable Cello® pulse
burner that operates over a range of frequencies. The Sonotech
system includes a combustion section, the tuning device or "trom-
bone," fuel and air systems, control and safety systems, a control
panel, and a support structure.
In a typical application, the Sonotech system is retrofit and
tuned to the process unit. Then it is operated at a combustion
system-specific frequency that excites intense sound and turbu-
lence within the process unit (see Figure 2). The intense sound
waves and turbulence are designed to increase the rates of mass,
momentum (or mixing), and heat transfer within the process,
resulting in fuel savings, increased productivity, lower emissions,
better productquality, and reduced maintenance. Sonotech claims
that their system has been shown to improve the performance of
both new and existing systems using conventional technology.
This section discusses the status of the Sonotech pulse com-
bustion technology as well as the developer's experience in
applying and retrofitting it to various industrial processes.
5.2 Completed Demonstrations
The SITE demonstration conducted at the ERF in Jefferson,
AR, was the third application of Sonotech's system to an incin-
eration process. The first and second demonstrations were both
carried out under the EPA Small Business Innovative Research
(SBIR) program at the EPA Air and Energy Engineering Re-
search Laboratory (AEERL) in Research Triangle Park, NC.
During the first demonstration, a bench-scale rotary kiln incin-
erator was retrofit with a frequency-tunable pulse combustion
system to enhance combustion efficiency. The system excited
large amplitude beneficial pulsations in the kiln and increased
combustion efficiency by promoting better mixing conditions in
the incinerator. The pulse combustor was operated in both steady
state and pulsating modes. Tests were performed using two types
of wastes:
1 Toluene sorbed onto a ground corncob sorbent placed in
cardboard containers
2 Polyethylene (such as crushed milk jugs and styrofoam
cups) placed in cardboard containers
During the second demonstration at AEERL, a second rotary
kiln furnace simulator was retrofit with the Sonotech system,
this second demonstration was designed to investigate whether
the Sonotech system allows the incinerator to burn liquid haz-
ardous wastes more efficiently than steady-state combustion.
The first two demonstrations were promising enough for the
Sonotech technology to be selected for the SITE demonstration
program. The SITE program demonstration at the IRF was also
supported by the Industrial Gas Technology Commercialization
Center of the American Gas Association.
The Sonotech system has also been applied commercially.
From 1987 to 1994, Sonotech conducted applied research in
cement pyroprocessing and applied an industrial-scale pulse
burner on a vertical U-shaped precalciner at the Holman Ce-
ment plant in La Porte, CO. This project was sponsored by the
Gas Research Institute (GRI) of Chicago, IL. The results of this
program will be available for public review in late 1996.
From 1991 to 1994, Sonotech developed a retrofit application
for a steel ladle preheater. The testing program showed that ret-
rofitting a ladle preheater station with a pulse burner can improve
the ladle's heating and reduce the ladle's specific heat consump-
tion, that is, the amount of fuel needed to heat ladle refractories.
Fuel consumption decreased by 9.2% with a corresponding
hourly temperature increase of 33.5%. This project was cospon-
sored by GRI and Atlantic Steel.
In 1994 Sonotech installed at a confidential commercial site
in California.
5.3 Ongoing Projects
Sonotech is currently working with Blue Circle Cement Com-
pany in Atlanta, GA to retrofit a rotary cement kiln with a
Sonotech pulse combustion system. The retrofit application is
expected to improve main burner flame pattern, improve heat
distribution from combustion gases to the load within the kiln,
and reduce pollutant emissions. The project is jointly sponsored
by GRI, Columbia Gas Distribution Company, Southern Natu-
ral Gas Company, and Atlanta Gas Light Company.
40
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Sonotech is also currently working with Centra-Union Gas of
Ontario, Canada, to improve environmental emissions, improve
heat transfer, decrease down time, and decrease the carbon con-
tent in the ash of large utility boilers. The demonstration project
is scheduled to run from May to October 1996. Tests will be
conducted at the Combustion and Carbonization Research Labo-
ratory run by Natural Resources Canada.
41
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Section 6.0
References
Acurex Environmental Corp. and PRC Environmental Manage-
ment, Inc. 1994. "Quality Assurance ProjectPlan for the SITE
Program Evaluation of the Sonotech Pulse Combustion Burner
Technology, Revision 2." September.
Code of Federal Regulations (CFR). 40 CFR Part 60, Appendix
A.
CFR. 40 CFR Part 61, Appendix B.
CFR. 40 CFR Part 261, Appendix B.
CFR. 40 CFR Part 266, Appendix IX.
Evans G., 1990. "Estimating Innovative Technology Costs for
the SITE Program." Journal of Air and Waste Management
Association. Volume 40, Number 7. July.
EPA, 1988a. "Compendium of Methods for the Determination of
Toxic Organic Compounds in Ambient Air, Second Edition,"
Atmospheric Research and Exposure Assessment Laboratory
in Office of Research and Development, EPA/600/4-89/017.
EPA, 1988b. "Guidance for Conducting Remedial Investigations
and Feasibility Studies under CERCLA." EPA/540/G-89/004.
October.
EPA, 1990. "EPA Methods Manual for Compliance with BIF
Regulations." EPA/530-SW-91-00. December.
EPA, 1992. "Test Methods for Evaluating Solid Waste, Volumes
IA-IC: Laboratory Manual, Physical/Chemical Methods; and
Volume II: Field Manual, Physical/Chemical Methods,
SW-846, Third Edition," Office of Solid Waste and Emer-
gency Response, Washington, D.C. November.
EPA, 1996. "SITE Program Evaluation of the Sonotech Pulse
Combustion Burner Technology." August.
42
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Appendix
Case Studies
This Appendix summarizes claims made by Sonotech regard-
ing the SITE Demonstration and the Sonotech frequency-tunable
pulse combustion process. The information presented represents
Sonotech's point of view; its inclusion in this Appendix does
not constitute EPA approval or endorsement.
This Appendix provides four case studies of the application
of the Sonotech frequency-tunable pulse combustion system in
various energy-intensive and incineration processes. Case S tudy
1 describes the application of the Sonotech system in water spray
evaporation experiments that simulated various aspects of the
spray drying processes; Case Study 2 describes the application
of the Sonotech system in limestone calcining, which is used in
cement manufacturing and the pulp and paper industry; Case
Study 3 describes the application of the Sonotech system in metal
heating, which is used in metal reheating and melting furnaces;
and Case Study 4 describes the application of the Sonotech sys-
tem in incineration. Case Studies 1 through 3 were conducted
by Sonotech, while Case Study 4 was conducted at the EPA IRF
as a part of the EPA SITE Program in cooperation with Sonotech.
1.0 Case Study 1: Effect of Pulsations on
Water Spray Evaporation
Case Study 1 was conducted by Sonotech between 1988 and
1989 under a contract entitled "Industrial Pulse Combustor De-
velopment and Its Application in Pulse Dryers," which was
supported by the GRI. The study had two primary objectives:
• Demonstrate that pulsations excited by the Sonotech sys-
tem can excite large amplitude pulsations in industrial-scale
processes
• Demonstrate that such pulsations can increase the efficiency
and productivity of water spray evaporation, which is one
of the controlling processes in spray drying
This study was the first effort to demonstrate that pulsations
can be used to increase the rates of mass, momentum (mixing),
and heat transfer processes, all of which control the performance
of most energy-intensive and incineration processes.
1.1 Program Description
This study was divided into two tasks. The first task investi-
gated the effect of pulsations on the minimum amount of fuel
required to completely evaporate a specific water spray flowrate
in a cylindrical tank that simulated a spray dryer. The second
task investigated the effect of pulsations on the maximum water
spray flowrate that can be completely evaporated with a specific
amount of fuel input to the spray dryer simulator. Both tasks are
discussed below, followed by a discussion of test results.
1.1.1 First Task Test Setup
The first task of Case Study 1 was conducted in a horizontal
cylindrical tank, 9 feet in diameter and 15 feet long. The tank
simulated a spray dryer, and a set of spray nozzles on the tank
was used to supply different water spray flowrates (see Figure
A-l). The configuration and number of spray nozzles could be
readily changed between tests. A Sonotech pulse combustion
system was installed on the tank wall about 2 feet from one end.
This system supplied the tank with a pulsating flow of hot com-
bustion products that was directed tangentially to the inner tank
wall. An exhaust duct installed at the opposite end of the tank
was used to remove water vapor and combustion products from
the tank. Water collected at the bottom of the tank was removed
through an open drain at the bottom of the tank next to the
Sonotech pulse combustor.
When the pulse combustor was operated at a frequency that
equaled one of the natural acoustic modes of the tank, large-
amplitude resonant pulsations were excited within the tank. The
effect of these pulsations on the minimum amount of fuel re-
quired to completely evaporate a given water spray flowrate,
supplied by a given arrangement of spray nozzles, was deter-
mined by repeating a given test with and without pulsations in
the tank. Operators then noted the minimum amount of fuel re-
quired to completely evaporate the water injected into the tank
by the spray nozzles.
A typical test was conducted by supplying the pulse combus-
tor with a specific fuel flowrate. After conditions in the tank
reached equilibrium, the water drain was inspected to determine
whether water was leaving the tank. If this was the case, fuel
input rate to the pulse combustor was increased, and the water
drain was inspected again for the presence of water. This proce-
dure was repeated until the pulse combustor fuel input rate
reached a value that produced no water leaving the tank through
its drain line, which indicated that all injected water sprays were
completely evaporated. For each test condition, this fuel flowrate
was determined in steady and pulsating tests.
43
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Testl
Test 2
A spray nozzle Smokestack
\
A
4
To
,-Drain
J
\
A spray nozzle Smokestack
\
Pu/se combustor
\
,-
J
Drain
Pulse combustor
Test3
Test 4
A spray nozzle Smokestack
I
JL
•4
•4
,Q
,-Drain
J
\
A spray nozzle Smokestack v
t
Pu/se combustor
Figure A«1. A schematic of the spray nozzle configuration used in Task 1 to investigate the effect of pulsations upon water spray
evaporation.
1.1.2 Second Task Test Setup
The second task of Case Study 1 was conducted in another
spray dryer simulator that consisted of a vertical cylindrical tank,
7 feet in diameter and 12 feet long, connected to a 4-foot-long
conical section at its base (see Figure A-2). Two spray nozzles
installed in the middle of the top of the tank were used to inject
a water spray into the system. The conical section had an open-
ing at its apex through which water could leave the dryer
simulator. A tunable pulse combustor was installed concentri-
cally in a larger diameter pipe used to supply a pulsating flow of
hot combustion products into the tank. The larger diameter pipe
supplied dilution air to the dryer simulator. The dilution air was
heated as it came in contact with the outside walls of the pulse
combustor before it entered the dryer simulator. By changing
the dilution air flowrate, the temperature and velocity distribu-
tions within the dryer simulator could be changed.
For these tests, the pulse combustor was operated with a fixed
fuel input rate of 500,000 Btu/hr, while the dilution air flowrate
was changed between tests. Each test was started by supplying
the tank with a water spray flowrate that did not completely
evaporate within the tank, resulting in an outflow of water through
tlie hole at the bottom of the conical section. Next, the water
spray flowrate was slightly decreased, lowering the water
flowrate leaving the tank. This process was repeated until water
stopped flowing out of the tank, indicating that the water spray
was completely evaporated within the tank. For each dilution
air flowrate, this test procedure was repeated with and without
pulsations in the dryer simulator, and the water spray flowrate
that was completely evaporated in each test was determined. The
resulting flowrate is the maximum amount of water that can be
completely evaporated in the tank under the investigated test
conditions.
1.2 Test Results
The results of the tests conducted as part of the first task are
summarized in Table A-l. Table A-l provides information on
the minimum pulse combustor fuel input rate, the total spray
water flowrate into the tank, the oxygen concentration in the
exhaust gas, the frequency and amplitude of the pulsations in
the tank, the temperature of the exhaust gases, the "evaporation
efficiency," and the percentage increase in "evaporation effi-
ciency" when pulsations were excited in the tank.
For all four spray nozzle configurations, the temperature of
gases in the exhaust stack was significantly lower when pulsa-
44
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Viewing
windows
Spray nozzle
Lighting
sources
*• Exhaust gases
Drain
Figure A-2. A schematic of the evaporator setup used in Task 2 to investigate the effect of pulsations upon water spray evaporation.
Table A-1. Evaporation Efficiencies for Task 1
Test
Number
1a
1b
2a
2b
3a
3b
4a
4b
M,
(MBtu/hr)
4.5
3.75
4
3.5
4.5
4.15
4.25
3.75
(Ib/hr)
1,863
1,863
1,743
1,743
2,134
2,134
1,983
1,983
Percent
02
7.2
7.9
7.4
7.2
7.2
7.9
8.5
8.4
Frequency
(Hz)
90
76
90
77
90
77
90
75
Pd
(mv)
1
20
1
15
1
15
1
15
T»
575
478
565
490
578
495
535
441
Efficiency
(Btu/lb)
2,415
2,013
2,295
2,008
2,109
2,185
2,143
1,891
Percent Increase
in Efficiency
Due to
Pulsations
16.67
12.50
7.78
11.76
Notes:
Evaporation efficiencies were measured during complete evaporation of sprays in Task 1 tests conducted under nonpulsating (Tests 1a, 2a
3a, and 4a) and pulsating (Tests 1 b, 2b, 3b, and 4b) conditions in the spray configurations shown in Figure A-1.
M, = Minimum fuel flowrate necessary to completely evaporate the water spray in million British thermal units per hour (MBtu/hr)
Minor = Water spray injected into evaporator in gpm
Percent O2 = Percent oxygen in the exhaust flow
Frequency = Frequency in cycles per second Hertz (Hz)
Pd = Amplitude of pulsations inside the evaporator in millivolts (mv)
T» = Temperature of exhaust gases in the stack in Fahrenheit (°F)
45
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lions were excited in the tank. Because the oxygen concentra-
tion of exhaust gases in pulsating and nonpulsating tests was
almost the same, the lower exhaust flow temperature in pulsat-
ing tests strongly suggests that a larger fraction of the energy
supplied by the Sonotech system was used to evaporate the wa-
ter spray. The last column in Table A-l shows that the pulsations
significantly reduced the minimum amount of fuel required to
completely evaporate various water spray flowrates in all of the
investigated test configurations by amounts that varied between
7.78%and 16.67%. These results show that pulsations increased
the thermal efficiency of the water spray evaporation, suggest-
ing lhatresonantpulsations could produce significant fuel savings
in a variety of drying processes.
The results of the second task are presented in Table A-2. Table
A-2 provides data on results obtained in a series of tests in which
the dilution flowrate was varied between 6,000 and 18,000
ft'/min. Two tests were conducted for each dilution air flowrate
with and withoutpulsations in the dryer simulator. The data show
that for all tests, pulsations increased the maximum amount of
water flowrate that could be completely evaporated with 500,000
Btu/hr fuel input to the combustor. These increases varied be-
tween 4.8% and 17.2%, and they indicate that the pulsations
increased the productivity of the dryer simulator. These results
arc consistent with those obtained in the first task of this study
(see Table A-l), and the observed increases in dryer simulator
productivity indicate that the pulsations reduced the amount of
fuel required to evaporate a unit mass of water spray flowrate.
The results of this task also indicate that pulsations could be
used to increase the capacity of a given dryer. Because it is ex-
pensive to increase the drying capacity of a given plant by
acquiring a new dryer, the results of Case Study 1 indicate that
the drying capacity of an existing plant could be increased more
economically by retrofitting the dryer with a Sonotech pulse
combustor.
Table A-2. Task 2 Maximum Water Flowrates to Completely
Evaporate Water
Dilution Air
Flowrato
(dsct/hr)
6,000
6.000
11,000
11.000
13.000
13.000
18.000
18,000
Maximum Water
Rowrate
(Ib/hr)
290.4
262.3
295.1
257.6
318.5
271.1
304.5
290.4
Pulsations
(yes/no)
yes
no
yes
no
yes
no
yes
no
Percent
Increase Due
to Pulsations
10.7
14.5
17.2
4.8
Notes:
FuoJ Flowrate - 500,000 Btu/hr
Combined Air Flowrate = 6.250 dscf/hr
Resonance amplitude in evaporator during pulsations = 149 dB
dsctthr = dry standard cubic feet per hour
Ibitir = pounds per hour
Blu/hr = British thermal units per hour
dB = decibel
2.0 Case Study 2: Effect of Pulsations on
Limestone Calcination
Limestone calcination, which involves the decomposition of
calcium carbonate (CaCO3) into calcium oxide (CaO) and CO2,
is an endothermic reaction used in many energy-intensive pro-
cesses such as cement clinkering, light weight aggregate
production, the pulp and paper industry, and flue gas desulfur-
ization. Calcination consists of heating a limestone powder and
removing the released CO2, a process similar to the heat addi-
tion and moisture removal processes that control drying
processes.
The effect of pulsations on limestone calcination was investi-
gated in two different studies. In the first series of tests, large
pieces of limestone with initial weights of about 360 grams each
were calcined in a duct attached to the tail pipe of a small pulse
burner capable of operating either in a steady or pulsating mode.
The limestone was calcined at a temperature of 1,800 °F in both
pulsating and steady-state tests, and calcination rates were de-
termined by periodically removing and weighing the calcining
limestone samples. The measured limestone calcination rate is
presented in Figure A-3. The slopes of the two plots describe the
calcination rate and show that the pulsations considerably in-
crease the limestone calcination rate. Because calcination is
controlled by the rates of heat transfer to and CO2 transfer from
the calcined particles, the test results indicate that pulsations in-
creased the rates of these transport processes.
In the second series of tests, limestones of different initial
weights were calcined as described above at a temperature of
1,720°F for 20 minutes under steady-state and pulsating operat-
ing conditions. The degree of calcination attained in each test
was determined by weighing the limestone before and after the
test. The percent weight losses obtained in the steady and pul-
sating tests are presented in Figure A-4. Because the data
exhibited considerable scatter, data obtained in steady and pul-
sating tests were correlated on a computer, and the correlations
are also presented in Figure A-4. The results show that pulsa-
tions increased the weight loss and increased the calcination rates
of particles of different sizes. These results also indicate that a
given calciner could operate at a lower fuel input rate to attain a
given rate of calcination. These conclusions suggest that the pro-
ductivity and thermal efficiency of a calciner can be increased
by retrofitting the process with a Sonotech pulse combustion
system.
3.0 Case Study 3: Effect of Pulsations on
Metal Heating
Case Study 3 investigated the effect of pulsations on the heat-
ing rate of a stainless-steel cylinder. The study was performed to
determine the influence of pulsations on metal heating. The po-
tential applications of this process include ferrous and nonferrous
metals production and metal reheating. The tests were conducted
in the experimental setup used in Case Study 2.
46
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80
60 -
c 40-
s.
20-
Pulsing
Steady state
20
40
Time, minutes
iii
60
80
Figure A-3. Comparison of limestone calcination rates attained in 1800°F pulsing and steady-state flow tests.
40
30 -
20 -
10
• Steady state
• Pulsating
10
20
30 40
Initial stone weight (g)
50
60
Figure A-4. Percentages of calcination attained by limestone having different initial weights in 20 minute steady and pulsinq test at
1720°F.
47
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3.1 Experiment Description
A stainless-steel cylinder, 3.5 inches in diameter and 7 inches
long, was placed in the tailpipe of a pulse burner. A thermo-
couple installed at the center of the cylinder was used to measure
tltc time dependence of the temperature in the cylinder. A sec-
ond thermocouple was used to measure the gas temperature just
upstream of the heated cylinder.
3.2 Tests Results
The effect of pulsations on the rate of heating the stainless-steel
cylinder was determined by comparing the measured rates of
temperature increase at the center of the sample. In each of the
two tests conducted, the cylinder was heated in the same tem-
perature gas in both pulsating and steady-state conditions. The
heating rates measured in these tests are presented in
Figure A-5. The results show that maximum temperatures of
l,417°Fand 1,353°F were reached in the center of the sample in
pulsating and steady-state conditions, respectively, indicating that
the sample can be heated to a higher temperature in a pulsating
environment. Figure A-5 also shows that pulsations measurably
reduced the time required to heat the sample to a specific tem-
perature. The sample was believed to be heated to a higher
temperature in the pulsating test because the oscillations de-
creased the thermal resistance between the hot gas and the sample
surface, resulting in higher convective heat flux to the sample
and sample surface temperature. These results suggest that pul-
sations increase the fraction of input energy transferred to the
heated metal sample and reduce the heating periods, indicating
that retrofitting a metal heating process with a Sonotech system
will produce fuel savings and will increase productivity.
4.0 Case Study 4: Effect of Pulsations on
the Rotary Kiln Incineration of
Superfund Waste
Scoping tests were performed at the EPA IRF in Jefferson,
AR, to establish optimal operating conditions for incineration of
wastes for the Sonotech SITE demonstration in the IRF RKS.
The waste used in the scoping runs discussed in this case study
consisted of coal, coal tar, and contaminated soil collected at the
abandoned Peoples coal gasification plant, a Superfund site lo-
cated in Dubuque, IA. During these scoping runs, the RKS was
co-fired with toluene to stimulate the formation of puffs during
the incineration of a hazardous waste. Because the amount of
waste remaining after the scoping runs was not sufficient for the
planned demonstration test runs, the waste was mixed with an-
other waste for the subsequent demonstration test runs. Test
conditions for the scoping test runs were similar to those dis-
cussed in Section 4 of this ITER. The scoping tests performed
for the SITE demonstration are presented as Case Study 4.
fp
I
1500
1400-
1300-
1200 -
1100 -
1000-
900-
800 -
700 -
600 -
500 -
400 1
300 -
ZOO 1
100 1
0
* Steady test
• Pulsating test
10
I
15
I I '
20
Time, minutes
\
25
I
30
\
35
40
Figure A-5. Temperature rise at the center of the cylinder under pulsating and steady heating conditions.
48
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4.1 Sonotech System Installation
Sonotech's pulse combustion burner system was delivered to
the EPA IRF in Jefferson, AR, on April 19, 1994. The system
was inserted through a 15-inch, outside diameter opening in the
rear wall of the incinerator's primary combustion chamber. The
Sonotech burner was mounted on special mounting rails, allow-
ing the installation or removal process to take only 20 minutes.
After completing a pulsating test, the Sonotech burner was re-
moved, and a door over the opening was securely tightened.
4.2 Test Results
The incinerator waste feedrate was the key parameter in all
tests. Both solids residence time and waste feedrate influence
ash quality (that is, the quality of the incinerator's solid waste
stream) and its emissions. The quality of the incinerator opera-
tion is determined by the ability of the incineration equipment to
Table A-3. Summary of Data Measured in Sonotech Scoping Runs
process wastes with appropriate residue quality and minimum
emissions to the environment.
After completing the trial runs and during preliminary tests,
the following changes were observed whenever the Sonotech
system was in operation:
• The temperature inside the primary chamber increased (see
Table A-3).
• The ash changed color from "charcoal black" to "gray."
• Videotape observations of the interior of the primary incin-
eration chamber showed a highly intense burning process,
which was apparently caused by improved mixing between
the reactants and improved heat transfer to the waste.
• After the trial runs, melted ash residue was observed on the
refractory surface. Such deposits could deteriorate refrac-
tory material and hinder program completion. To resolve
Date
Waste feedrate (Ib/hr)
Co-fire, toluene (Ib/hr)
Kiln speed (rpm)
Temperature (°F):
Gas analysis (average):
Test Conditions
Kiln exit
Afterburner exit
Stack
Kiln exit: O2, %
CO, ppm
Afterburner exit: O2, %
Main burner fuel consumption, dscf/hr
Main burner air flow, dscf/hr
Pulse burner fuel consumption, dscf/hr
Pulse burner air flow, dscf/hr
Afterburner fuel consumption, dscf/hr
Afterburner air flow, dscf/hr
Total fuel consumption, dscf/hr
Total fuel consumption per pound of waste, dscf/hr
Ash content, %
Ash heating value, Btu/lb
Notes:
O = Oxygen
CO = Carbon monoxide
CO2 = Carbon dioxide
NOX = Nitrogen oxides
TUHC = Total unburned hydrocarbons
Ib/hr = Pound per hour
rpm = Revolutions per minute
°F = Degree Fahrenheit
ppm = Parts per million
dscf/hr = Dry standard cubic foot per hour
Btu/lb = British thermal unit per pound
n/a = not analyzed
C02, %
CO, ppm
Stack exit: O2, %
CO, ppm
NOX, ppm
TUHC, ppm
Test 1
6/6/94
102.1
9.8
0.09
1,550
2,000
156
8.9
157
9.3
8.0
10.5
11.3
14.3
72.6
0.9
687
14,920
0
0
1,050
7,920
1,740
17.0
91
n/a
Test 2
6/6/94
132.5
8.3
0.09
1,570
2,010
161
7.6
573
8.3
8.9
39.2
10.7
37.7
83
n/a
592
14,020
0
0
950
7,420
1,540
11.6
64
5,980
Tests
6/7/94
135
6.8
0.09
1,620
2,000
171
10.6
193
7.6
8.3
7.0
10.2
8.0
63
n/a
245
10,360
200
3,030
1,000
7,940
1,450
10.7
94
583
Test 4
6/9/94
156
8.0
0.094
1,550
2,000
175
7.6
680
8.0
9.2
46.8
10.8
28.6
66.3
n/a
0
13,820
200
3,040
900
7,900
1,100
7.1
66
5,100
49
-------
this problem, the operating temperature inside the
incinerator's primary chamber was gradually reduced until
no deposits were observed on the refractory surface.
These visual observations and recorded changes in monitored
continuous emissions show that Sonotech system improved the
rates of heat, mass, and momentum (mixing) transfer inside the
primary chamber of the RKS. Results of ash test analyses on the
heating value of the treated waste collected from the ash bin
confirmed these observations.
Table A-3 presents data on the parameters monitored to char-
acterize the operation and performance of the RKS during the
two steady-state tests (Test Conditions 1 and 2, representing
baseline and marginal incinerator operation, respectively) and
two pulsating tests (Test Conditions 3 and 4, which are the
Sonotech counterparts of steady-state Test Conditions 1 and 2,
respectively).
4.3 Data Analysis
The data presented in Table A-3 represent averages of data
collected by a fast data acquisition system. Table A-4 presents a
comparison of results obtained in the steady and pulsating tests
and shows the benefits produced by Sonotech's pulse combus-
tion system. Equations depicting how observed benefits were
calculated arc shown and the terms in the equations are defined.
Table A-4. Benefits Provided by the Sonotech System
Waste feedrate increase (AG) 18% to 32%
CO emissions reduction (EH™)
Kiln exit 66%
Afterburner exit 82%
Slack exit 79%
NO emissions reduction (EFUJ at the stack 24%
Fuel savings (AB) 8.0% to 39%
Ash quality increase (ash heat content decrease) (6) 90%
Waste Feedrate
The waste fcedrate increase when the Sonotech system was
operating was determined using the following equations and
assumptions:
1. The waste feedrate increase attainable when the Sonotech
pulse combustor is operated can be expressed as:
AG-{(G4-G2)/G2HOO
where
AG - Percent increase in waste feedrate
G, - Waste feedrate for condition i in Ib/hr
2. Because incinerator operation under Test Condition 3 is
considered "corrected to normal," it is logical to compare
"normal conventional" to "normal pulsating" operation.
The following formula was used to compute the increase
in waste feedrate:
Carbon Monoxide
Producing large amplitude beneficial pulsations inside the
primary chamber of RKS allowed the main burner to be turned
off, sustaining the incineration process for Test Condition 4 with
the Sonotech burner operating as an acoustic mixer and burner.
Such operation indicates that improved mixing, caused by pul-
sations, makes it possible to release more heating value from the
waste. Additional increases in the waste feedrate were not pos-
sible due to the limited operating capabilities of the incinerator's
feed conveyer. When the incineration system reached its physi-
cal limit, a waste feedrate of 156 Ib/hr was accepted as the
maximum value.
The effect of large amplitude beneficial pulsations to reduce
CO emissions was computed using the following equation:
ERco=«COcm2-COcm3)/COcm2}-100
where
ERCO = Percent reduction in CO emissions
COcm2 = Averaged emission level of CO in ppm at the kiln
exit, afterburner exit, and stack exit, obtained in Test
Condition 2
COcm3 = Averaged emission level of CO in ppm at the kiln
exit, afterburner exit, and stack exit, obtained in Test
Condition 3
Nitrogen Oxides
The percent reduction in NOx emissions was obtained by com-
paring the averaged data from "tests 2 and 3, because these tests
were conducted at the same waste feedrate. The percent reduc-
tion in emissions of NOx was determined as follows:
ERNOX=«NOX2-NOX3)/NOX2HOO
where
ERNOx = Percent reduction in NOx emissions
NOx2 = Averaged NOx emission level in ppm under Test Con-
dition 2
NOx3 = Averaged NOx emission level in ppm under Test Con-
dition 3
Fuel Consumption
Comparing the total system fuel consumption (including the
main kiln burner, Sonotech burner, and afterburner) for Test
Condition 3 to that for Test Condition 2 shows that, at the same
waste feedrate, the Sonotech system allowed a fuel savings of
6.2%. In addition, the Sonotech system allowed a higher waste
feedrate to be achieved under comparable operating conditions.
Specifically, the waste feedrate achievable for Test Condition 4
was 15% greater than for Test Condition 2, under comparable
incinerator operating conditions and with an ash product of com-
parable heat content. Furthermore, because the waste incinerated
had significant heat content, the increase in feedrate corresponds
to a decrease in the amount of fuel needed to incinerate a unit
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mass of waste. Specifically, the increased feedrate of Test Con-
dition 4 corresponds to a 39% reduction in the Btu of fuel needed
per pound of waste incinerated, when compared to Test Condi-
tion 2.
Incineration Quality
Incineration quality is measured by the heat content of the
discharged ash. The increase in incineration quality was calcu-
lated by comparing data obtained from Test Conditions 3 and 2,
because these two test conditions were performed at the same
waste feedrate. The following equation was used to calculate
the increase in incinerator quality:
where
9= Percent increase in incineration quality
Qadi2 = Average percent of heat content of the ash contained in
the treated waste, obtained from Test Condition 2
s= Average percent of heat content of the ash contained in
the treated waste, obtained from Test Condition 3
5.0 Conclusions
All data obtained in Case Studies 1 through 4 indicate that
retrofitting an energy-intensive or incineration process with
Sonotech's frequency-tunable pulse combustion system will
improve the process and produce all or some of the following
operating benefits:
• Reduced pollutant emissions
• Decreased auxiliary fuel requirement
• Increased process throughput
• Improved process and product quality
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*U.S. GOVERtMEOT PRINTING OFFICE: 1997-551-913
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