EPA-600/2-78-020
March 1978
Environmental Protection Technology Series
PARTIAL CHARACTERIZATION OF
CHLORINATED ORGANICS IN
SUPERCHLORINATED SEPTAGES AND
MIXED SLUDGES
Municipal Environmental Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency, have been grouped into nine series. These nine broad cate-
gories were established to facilitate further development and application of en-
vironmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The nine series are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
8. "Special" Reports
9. Miscellaneous Reports
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop and dem-
onstrate instrumentation, equipment, and methodology to repair or prevent en-
vironmental degradation from point and non-point sources of pollution. This work
provides the new or improved technology required for the control and treatment
of pollution sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.
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EPA-600/2-78-020
March 1978
PARTIAL CHARACTERIZATION OF CHLORINATED ORGANICS
IN SUPERCHLORINATED SEPTAGES AND MIXED SLUDGES
by
Robert H. Wise
Thomas A. Press!ey
Barry M. Austern
Wastewater Research Division
Municipal Environmental Research Laboratory
Cincinnati, Ohio 45268
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
CINCINNATI, OHIO 45268
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DISCLAIMER
This report has been reviewed by the Municipal Environmental Research
Laboratory, U.S. Environmental Protection Agency, and approved for publication.
Mention of trade names or commercial products does not constitute endorsement
or recommendation for use.
ii
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FOREWORD
The Environmental Protection Agency was created because of increasing
public and government concern about the dangers of pollution to the health
and welfare of the American people. Noxious air, foul water, and spoiled
land are tragic testimony to the deterioration of our natural environment.
The complexity of that environment and the interplay between its components
require a concentrated and integrated attack on the problem.
Research and development is that necessary first step in problem
solution, and it involves defining the problem, measuring its impact, and
searching for solutions. The Municipal Environmental Research Laboratory
develops new and improved technology and systems for preventing, treating,
and managing wastewater and solid and hazardous waste pollutant discharges
from municipal and community sources, for preserving and treating public
drinking water supplies, and for minimizing the adverse economic, social,
health, and aesthetic effects of pollution. This publication is one of the
products of that research and is a most vital communications link between the
researcher and the user community.
This report describes the results of an analytical study performed on
sludges and septages that were chemically stabilized with the proprietary
Purifax superchlorination process. The superchlorination process is a
technological solution to the problem of sludge bio-instability. Knowledge
of the end products of the superchlorination provides insight into potential
environmental impacts from the sludges and wastewaters discharged from the
superchlorination process.
Francis T. Mayo
Director
Municipal Environmental
Research Laboratory
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ABSTRACT
The chlorinated organic materials produced by applying the proprietary
Purifax process (i.e., stabilization by superchlorination) to a septage
and a mixed primary/secondary sludge were identified in both the solid and
liquid phases to assess the types, amounts, and distribution of chlorinated
organics present.
Total organic chlorine concentrations of the solid phases were
determined by Schoniger-flask combustion techniques. Total organic chlorine
concentrations for concentrated hexane-ether extracts of the liquid phases
were determined by microcoulometric titration. These same concentrated
hexane-ether extracts, as well as the helium-purgeable "volatile" organics
from the unextracted liquid phases, were then analyzed by gas chromatography/
mass spectrometry. Analyses for total organic carbon, total dissolved
solids, and total suspended solids were also performed on the liquid phases
from one location to furnish engineering data for assessing both the feasi-
bility and cost of applying filtration/carbon adsorption as an adjunct to
Purifax treatment.
The amounts of organic chlorine found in the Purifaxed solids were
relatively large (1% by weight); however, the identities of these compounds
remain unknown because of analytical limitations. The specific compounds
identified in the liquid phases do not, by themselves, eliminate super-
chlorination as an environmentally acceptable process these compounds
(except in lower concentrations) are the same types as those presently
found in contaminated surface waters. Still lacking is information about
chlorinated gaseous organics released to the atmosphere when Purifaxed
materials are discharged from the reactor.
This report covers a period from February 1977 to July 1977, and work
was completed as of August 1977.
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CONTENTS
Foreword iii
Abstract iv
Tables vi
Acknowledgments vii
1. 'Introduction 1
2. Conclusions 2
3. Recommendations 4
4. Experimental Procedures 5
Sample sources, procurement, and storage 5
Preparation of samples for analysis 6
Determination of percent total organic chlorine
in the solids fractions 8
Determination of total, hexane-ether extractable,
non-volatile organic chlorine in the liquid
phases (i.e., centrates) 10
Determination of individual, helium-purgeable,
organic compounds in the liquid phases 11
Determination of individual, hexane-ether
extractable, non-volatile organic compounds in
the liquid phases 11
Determination of additional parameters for
Ventura centrates to permit cost calculations
for filtration/carbon adsorption as an adjunct
to Purifax treatment 15
Discussion 19
References 21
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TABLES
Number Page
1 Percent Total Chlorine, Inorganic Chloride, and
Organic Chlorine in Air-Dried Solids 9
2 Percent Total Organic Chlorine Based on Oven-Dried
Solids 9
3 Percent Total, Hexane-Ether Extractable, Non-Volatile
Organic Chlorine in the Liquid Phases 10
4 Concentrations of Helium-Purgeable Organic Compounds
in Both Raw Samples 12
5 Concentrations of Helium-Purgeable Organic Compounds
in Both Dechlorinated Samples 13
6 Concentrations of Helium-Purgeable Organic Compounds
in Both Chlorinated Samples 14
7 Concentrations of Hexane-Ether Extractable, Non-Volatile
Organic Compounds in Both Raw Samples 16
8 Concentrations of Hexane-Ether Extractable, Non-Volatile
Organic Compounds in Both Dechlorinated Samples .... 17
9 Concentrations of Hexane-Ether Extractable, Non-Volatile
Organic Compounds in Both Chlorinated Samples 18
10 Miscellaneous Engineering Parameters for Ventura
Centrates 19
VI
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ACKNOWLEDGMENTS
We gratefully acknowledge the cooperation of Ray Thompson, Chief,
Surveillance & Analysis Division, Region I (EPA), and the Plainfield,
Connecticut, Wastewater Treatment Plant personnel, who cooperated to furnish
the samples of mixed primary/secondary sludges.
We are also indebted to Robert Miele and Kieran Bergin of the Los
Angeles County Sanitation Districts and to Joseph Borgerding of the Ventura
County Regional Sanitation District for furnishing the samples of Ventura
septages used in this study.
VII
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SECTION 1
INTRODUCTION
The proprietary Purifax process is one of several systems able to
stabilize and disinfect sludges or septage before land disposal. When
required, it also is used to treat anaerobic digester supernatant.
Briefly, the Purifax process is a method developed by BIF (a unit of
General Signal Corporation) for superchlorinating concentrated biological
wastes (for example, sludges and septages) to stabilize the active
solids biologically and thus enhance their dewatering characteristics.
Competing processes for the sludge treatment function include lime
stabilization, heat treatment, wet air oxidation and anaerobic digestion.
Lime and polymer treatment with air stripping of ammonia is an alternative
for treatment of digester supernatant. The Purifax process, as currently
practiced with chlorine costs of typically $12/ton of treated sludge, is
competitive with the alternative treatment processes.
The very high concentrations of chlorine (approximately 700 to 3,000
rog/1) typically employed during the Purifaxing of septages and sludges
are also capable of producing chlorinated organics. Limited analytical
results on chlorinated organics from Purifaxed septages have already been
reported by Mashni (1). Before Mashni's work, the engineering firm of
Metcalf and Eddy (2) reported their analytical studies of five different
waste streams, each taken from a different geographical location. All of
those waste streams were being routinely subjected to Purifax treatment at
the time samples were taken. The specific compounds of interest to Metcalf
and Eddy were nine chlorinated herbicides (including 2,4-D and 2,4,5-T),
five chlorinated insecticides, and polychlorinated biphenyls. Rather than
producing any of these objectionable compounds, Purifaxing actually seemed
to lower their concentrations in most instances. Since that time, the
volatile organics analysis method of Bellar and Lichtenberg (3) has been
reported, and computerized gas chromatograph/mass spectrometer (GC/MS)
systems have become widely available. This, in turn, has led to the
discovery that waters and wastewaters often contain a far greater variety
of undesirable chlorinated organic contaminants than those studied by
Metcalf and Eddy, especially when organically contaminated aqueous waste
streams are deliberately chlorinated for disinfection or waste stabilization.
The present study of Purifaxed wastes was performed to determine what
types of chlorinated organics are thus produced, how such compounds are
likely to be discharged (that is, primarily as constituents of the solids
phase, the liquid phase, or both) and, in each case, how much. With the
information thus obtained, at least a tentative evaluation of the environmental
risks associated with this process is possible.
1
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SECTION 2
CONCLUSIONS
Purifaxed samples of one septage and one mixed primary/secondary sludge
were each separated into solids and liquid phases, then analyzed for their
organic contents by a variety of different techniques.
Both solids fractions contained 0.9% to 1.0% total organic chlorine,
based on dry weight. No attempt was made to identify individual organic
constituents in these relatively insoluble solids.
Hexane-ether extracts of both liquid fractions assayed approximately
100 to 200 ug/1 of total organic chlorine, or less than 1% of the total organic
contents of the unextracted liquid phases. GC/MS analyses, both of the
hexane-ether extracts and of the helium-purgeable, volatile organics in the
unextracted aqueous phases, yielded slightly higher concentrations of the
same kinds of organic compounds that are typically present in U.S. water
supplies. A notable exception, however, was the highly toxic cyanogen
chloride, present in all of the unextracted Purifaxed liquid phases in
concentrations reaching 900 yg/1.
The centrate from Ventura contained approximately 200 mg/1 of TOC, and
less than 1 mg/1 of this TOC was identified as specific organic molecules.
The unidentified TOC is non-volatile and non-extractable and therefore
cannot be analyzed by GC/MS methods. The amounts of chlorinated organics
in that TOC are unknown.
Standards governing maximum permissible concentrations for the organic
compounds found in the Purifaxed liquid phases have not yet been established
for drinking water supplies and wastewater discharges. Environmental impacts
of these molecules depend on site-specific dilution factors. Thus,
Robert Tardiff of the Health Effects Research Laboratory in Cincinnati
has indicated that the identified organics in the liquid centrates entering
the environment do not by themselves constitute a basis for environmental
unacceptability of the Purifax process (Personal communication).
Finally, the long-term environmental impact of the chlorinated organics
in the Purifax solids placed in landfills or on soils are unknown. The
organics are likely to include chlorinated proteins and amino acids, humic
acids, carbohydrates, and fats. The toxicity of these chlorinated materials
is unknown, but since the chlorinated sludge resists biodegradation, the
chlorinated organics are probably biocidal (at least to bacteria).
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The work carried out during this project does not represent a definitive
study of chlorinated organic material produced by the Purifax treatment of
septages and sludges. To carry out such a definitive study is beyond the
current state-of-the-art and would require major-scale analytical resources
(work space, trained manpower, time, and sophisticated analytical equipment)
for analytical methods development.
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SECTION 3
RECOMMENDATIONS
We recommend that no further direct chemical analyses of the solid or
liquid phases be carried out at this time.
In the Purifax process, a gaseous phase is also discharged from the
reactor, along with the solid and liquid phases. An analysis of this gas
phase should be carried out.
Other fruitful approaches to this problem would include:
a) Controlled studies of the extent to which chlorinated material
in Purifaxed solids is leached from landfills over extended
periods of time.
b) Suitable toxicological studies (for example, animal feeding studies)
to ascertain the occurrence and severity of any adverse health
effects resulting from the chlorinated material in Purifaxed
liquids entering drinking water supplies.
c) Determinations of the extent of environmental persistence of
chlorinated organics produced by the Purifax process; or,
conversely, the rate at which such chlorinated organics are
biodegraded in natural environments.
Naturally, approaches a and c would require considerable analytical support
and extensive analytical methods development.
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SECTION 4
EXPERIMENTAL PROCEDURES
SAMPLE SOURCES, PROCUREMENT, AND STORAGE
Original plans called for us to receive two samples from Region I:
a superchlorinated septage, and a superchlorinated mixture of septage plus
primary/secondary sludge. Because of severe winter snows throughout most
of Region I from January through March of 1977, septage collections in that
Region were brought to a standstill. When it became apparent that septage
would not be available for an indeterminate period, arrangements were made
for shipment of a Purifaxed primary/secondary sludge (plus a representative
unchlorinated control) from the Plainfield (Connecticut) Wastewater Treatment
Plant with the understanding that our septage samples probably would have to
be obtained elsewhere.
Purifaxing was carried out on February 9, 1977, using 21.8 kg (48 Ib)
of chlorine to treat 15,369 1 (4,060 gal) of mixed sludges (1,417 mg Cl/1).
Typically, free chlorine residuals for the product leaving this reactor had
averaged 300 mg/1. The Purifaxed sample was divided into two portions
immediately after collection. One portion was packaged for shipment with its
free chlorine content intact; this sample was labeled "chlorinated sludge."
The other portion was allowed to stand 4 hours, then it was dechlorinated
with sodium sulfite solution and also packaged for shipment. This sample was
labeled "dechlorinated sludge." Because both Purifaxed samples had been
biologically stabilized, they could be handled without any further need for
sample preservation. The required control sample for this work (that is, an
untreated portion of the raw sludge fed to the Purifax unit) was highly
unstable; therefore, it had to be packed and shipped in an insulated container
filled with ice. This control sample was labeled "raw sludge."
All three samples were sent by Federal Express and arrived at our
laboratory less than 24 hours after shipment. All of these samples were
immediately placed in a walk-in cold-room until they could be readied for
analysis.
The Purifaxed septage needed for this study was obtained from the Ventura
County (California) Regional Sanitation District. Their Purifax treatment
facility was operated solely on a septage feed for this project. The applied
chlorine dosage was about 800 to 1,000 mg Cl/1; 4 hours after Purifaxing, the
free residual chlorine concentration had decreased to 90 mg/1.
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Sampling, packaging, and shipping protocol for the Ventura samples was
identical to that for the samples from Plainfield, except that the
Ventura samples were labeled "chlorinated septage," "dechlorinated septage,"
and "raw septage" (that is, the chlorinated septage was shipped with its free
residual chlorine content intact; the dechlorinated septage was treated with
Na2$03 solution 4 hours after Purifaxing; and the raw septage feed to the
Purifax unit was shipped in an ice pack). These three samples, also received
less than 24 hours after shipment, were immediately stored in a cold-room.
All the chlorinated samples were tested (qualitatively) for free
residual chlorine approximately 48 hours after Purifaxing. No remaining free
residual chlorine could be detected. Thus, in only 2 days, the 90 to 300 mg
Cl/1 that these samples had originally contained when they were shipped was
no longer present.
PREPARATION OF SAMPLES FOR ANALYSIS
Approximately 1,500 ml of each sample slurry was batch-centrifuged at
1,800 rpm until a clear centrate resulted; this required anywhere from 20
minutes to 6 hours, depending on each sample's unique dewatering character-
istics. The clear liquid fraction was carefully decanted into a glass-
stoppered bottle and returned to the cold-room. The tightly packed,
damp, solid fraction was spread out on a watch glass and air-dried in a hood
for at least 3 days.
Each air-dried solid fraction was pulverized and thoroughly macerated
with a mortar and pestle. The somewhat fibrous powder was stored in tightly
closed, screw-cap vials for subsequent determination of percent total organic
chlorine via the Schoniger-flask method.
Eight hundred milliliters of each clear centrate was extracted with
three 60-ml portions of 85% hexane-15% diethylether (Burdick and Jackson
high-purity solvents were used exclusively throughout this project). The
three 60-ml extracts of each centrate were combined and dried overnight with
20 g of anhydrous Na2$0/i. A separate 180-ml portion of the mixed extraction
solvent was also treated with NaoSO/^; this solvent blank was carried through
all subsequent operations, including all analyses involving these extracts.
Each dried extract was decanted from the settled Na2SO^ through solvent-washed
glass wool; the filtrate was collected in a Kuderna-Danish flask fitted with
a removable 10-ml graduated thimble. A Snyder condenser was attached to each
K-D flask, and the extracts were concentrated on a hot-water bath to about
10 ml. Each extract was further concentrated to a final volume of 0.9 to
1.0 ml by a combination of judicious heating, plus a fine stream of inert gas
directed on the surface of the extract. Each K-D thimble was tightly
stoppered and refrigerated until its contents could be brought back to a
room-temperature volume of 1.0 ml by addition of pure hexane. Each extract
was then transferred to a teflon-faced septum vial for subsequent GC/MS study
and for determination of total, hexane-ether extractable, non-volatile organic
chlorine via microcoulometric titration.
Figure 1 is a line diagram illustrating the sequence of sample preparation
steps required before the analyses described as follows.
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Raw Sample
y (Purifax Chlorination)
(Centrifugation)
(Centrifugation)
:°/;
(Same as scheme shown on the right)
Helium-Purgeable
Organic Compounds
Total Organic
Chlorine
Miscellaneous
•Parameters
for Engineering
Calculations
Total Non-
Volatile Organic
Chlorine
Individual Non-
Volatile Organic
Compounds
Figure 1. Flow sheet for sample processing and analysis of purifaxed sludges and septage
(A "control" portion of raw sample was carried through the same laboratory
operations and analyses as shown on the right-hand side of the figure.)
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DETERMINATION OF PERCENT TOTAL ORGANIC CHLORINE IN THE SOLIDS FRACTIONS
Procedure
Analyses for total organic chlorine in the solids fraction were carried out
using a modified Schb'niger-flask combustion procedure described by Welcher and
Ma (4). This is a method whereby a weighed amount of each sample (in our case,
the air-dried solids) is burned in a specially designed flask, containing pure
oxygen and a suitable liquid reagent for absorbing (and neutralizing) the acidic
combustion products. During combustion, chlorinated organic compounds yield
C02, HC1, and (if sulfur is present) S0£ and/or $03, all of which are absorbed
as soluble salts. After destruction of possible interferences, the contents of
the flask are transferred quantitatively to a beaker. Chloride ion is then
titrated potentiometrically with standard AgNOo solution to permit calculation
of the total chlorine content of the sample. If, as in our case, the sample
contains both organic and inorganic chlorine (that is, free chloride ion), a
separate portion of the unburned sample must be boiled with deionized water to
dissolve inorganic chloride; the free chloride ion is then titrated with AgNOo.
This permits calculation of percent organic chlorine by difference:
Percent organic Cl = percent total Cl - percent free chloride ion.
Since each sample of air-dried solids contained an unknown and variable
concentration of residual moisture, values for percent organic chlorine in
air-dried solids had to be correspondingly adjusted; otherwise, meaningful
comparisons of data might not have been possible. Accordingly, separate
weighed portions of the air-dried solids were oven-dried to constant weight at
105 to 110 C. The percentages of oven-dried solids were calculated and used
to adjust the Schbniger values to true organic chlorine (percent organic
chlorine based on dry solids). By coincidence, every batch of air-dried
solids assayed 95±1%, expressed as oven-dried solids.
Results
The Schoniger results for both sets of air-dried samples are shown in
Table 1.
The values in Table 1 for percent organic chlorine in air-dried solids
were mathematically converted to the corresponding values for oven-dried
solids (Table 2). The values shown in Table 2 are not as insignificant as
might appear at first glance. For example, assume that the number-average
equivalent weight of chlorinated organics in the solids phases is only 350
(a number that is probably far too small). Then a 1% concentration of total
organic chlorine represents a 10% concentration of monochlorinated organic
compounds. If a more realistic number-average equivalent weight of 700 is
assumed, then 1% of total organic chlorine represents 20% as monochlorinated
organic compounds. These are certainly very significant concentration levels.
8
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TABLE 1. PERCENT TOTAL CHLORINE, INORGANIC CHLORIDE, AND ORGANIC
CHLORINE IN AIR-DRIED SOLIDS
Purifaxed primary/
Parameter secondary sludge solids, %
Total Cl in raw sample
Inorganic Cl in raw
sample
Organic Cl in raw sample
Total Cl in dechlorinated
sampl e
Inorganic Cl in
dechlorinated sample
Organic Cl in dechlorinated
sample
Total Cl in chlorinated
sample
Inorganic Cl in
chlorinated sample
Organic Cl in chlorinated
sample
0.09, 0.07
Not detectable
0.08
2.52, 2.59
1.67, 1.67
0.89
2.64, 2.66
1.80, 1.83
0.83
Purifaxed
septage solids, %
0.15,
0.05,
0.14
2.26,
1.31,
0.97
3.00,
2.08,
0.94
0.21
0.04
2.28
1.28
2.99
2.04
TABLE 2. PERCENT TOTAL ORGANIC CHLORINE BASED ON OVEN-DRIED SOLIDS
Purifaxed primary/ Purifaxed
Parameter secondary sludge solids, % septage solids.
Organic Cl in raw sample 0.08 0.15
Organic Cl in dechlorinated 0.94 1.01
sample
Organic Cl in chlorinated 0.87 0.98
sample .
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DETERMINATION OF TOTAL, HEXANE-ETHER EXTRACTABLE, NON-VOLATILE ORGANIC
CHLORINE IN THE LIQUID PHASES (i.e., CENTRATES)
Procedure
These analyses were carried out on the 1.0-ml concentrates obtained by
hexane-ether extractions of sample centrates. The methodology involves
microcombustion of a known volume of sample or extract, followed by
microcoulometric titration of the resulting halogen acids (in our case, HC1)
with silver ion in a special cell designed for this purpose. The equipment
and related procedure is available from the Dohrmann Division of Envirotech
Corporation as their microcoulometric titration system, MCTS-20-D. Just
before each day's analyses, the equipment is checked and calibrated with a
suitable standard solution of a pure organic halogen compound dissolved in
iso-octane.
Results
The values for total halogen, expressed as Cl, for both sets of centrates
are shown in Table 3.
TABLE 3. PERCENT TOTAL, HEXANE-ETHER EXTRACTABLE, NON-VOLATILE
ORGANIC CHLORINE IN THE LIQUID PHASES
*yg Cl/1 of centrate
Purifaxed primary/
Sample centrate secondary sludge Purifaxed septage
Raw sample 0.9 25.4
Dechlorinated sample 73.4 136
Chlorinated sample 134 170
*Each value shown is the average of replicate microcoulometric titrations,
10
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DETERMINATION OF INDIVIDUAL, HELIUM-PURGEABLE, ORGANIC COMPOUNDS IN THE
LIQUID PHASES
Procedure
These determinations were carried out by combining the purge-and-trap
technique described by Bellar and Lichtenberg (3), with GC/MS detection and
analysis of the volatile (trapped-out) organic compounds in each of the
liquid phases. A suitable aliquot of liquid sample was purged for 11 min
at room temperature with 20 ml/min of helium. The gaseous effluent was passed
through a Bellar trap, the first 60% of which was packed with 60/80 mesh
Tenax-GC, and the last 40% with Davison grade 15 silica gel. Direction of gas
flow was such that the purged organics contacted first the Tenax, then the
silica gel. The trapped organics were thermally desorbed for a period of
3 min using a 200 C flash heater on the trap. During this time, the desorbed
organics.were swept by 20 ml/min of helium into the injection port (200 C)
of a Finnigan Model 9500 gas chromatograph equipped with a 1.52-M (5-ft) x
2-mm ID glass column packed with 60/80 mesh Tenax-GC and maintained at a
temperature slightly below 50 C. After the trap had been flash-heated for
3 min, temperature programming of the GC column was immediately begun for a
30-min run. Column temperature was increased at a rate of 8°/min from 50 C
to 190 C, and it was held at the latter temperature until the 30-min run was
over. All during the GC run, automatic data acquisition and display were
accomplished with a directly interfaced Finnigan, Model 3300, mass spectro-
meter system. The mass spectrometer was operated in the electron impact (El)
mode at 70 eV and 10"? amps/volt sensitivity. The chosen mass range was 20
to 260 atomic mass units with 4-sec scans.
Because of pronounced foaming properties of the Purifaxed samples, only
well-diluted 1.0-ml aliquots could be analyzed. That is, each 1.0-ml aliquot
had to be diluted to 5.0 ml with boiled Milli-Q water before the purge-and-trap
step. On the other hand, undiluted 5.0-ml aliquots of both the raw sludge
and raw septage could be analyzed with no difficulty, as could 5.0-ml aliquots
of calibration standards.
Results
The values for helium-purgeable, volatile organic compounds in raw
dechlorinated, and chlorinated samples are listed in Tables 4, 5, and 6,
respectively.
DETERMINATION OF INDIVIDUAL, HEXANE-ETHER EXTRACTABLE, NON-VOLATILE ORGANIC
COMPOUNDS IN THE LIQUID PHASES
Procedure
The concentrated hexane-ether extracts that had already been analyzed
for total non-volatile organic chlorine were further reduced in volume to
0.5 ml each, then analyzed for individual organic compounds via GC/MS. The
conditions for each GC/MS analysis were as follows:
11
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TABLE 4. CONCENTRATIONS OF HELIUM-PURGEABLE ORGANIC COMPOUNDS
IN BOTH RAW SAMPLES
Trapped volatile
compounds
Concentration of compound, ug/1
Mixed primary/
secondary sludge
Septage
Methyl chloroform
Benzene
Dimethyldisulfide
Ethanol
Acetone
Dichloromethane
1, 1-DichloroetJiane
Chloroform
Dithiabutane
Toluene
Xylenes
Chiorotoluenes
Dichlorobenzenes
Methanethiol
2,3,4-Tri thi apentane
5
10
150
Not quantified
Not quantified
60
2
Not quantified
Not quantified
1
60
8
150
75
50
95
100
12
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TABLE 5. CONCENTRATIONS OF HELIUM-PURGEABLE ORGANIC COMPOUNDS
IN BOTH DECHLORINATED SAMPLES
Trapped volatile
compounds
Concentration of Compounds, yg/1
Mixed primary/
secondary sludge Septage
Cyanogen chloride
Dichloromethane
Chloroform
Carbon tetrachloride
Benzene
Ethanol
Acetone
3-Methylbutanal
Toluene
Hexanal
Furfural
Chloroethane
1, 1-Dichloroethane
Methyl chloroform
Di chloroaceton i tri1e
Chiorotoluenes
Dichlorobenzenes
n-Valeronitrile
700
100
100
30
5
Not quantified
Not quantified
Not quantified
2
Not quantified
Not quantified
170
10
65
Not quantified
Not quantified
Not quantified
60
3
85
40
50
130
300
Not quantified
13
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TABLE 6. CONCENTRATIONS OF HELIUM-PURGEABLE ORGANIC COMPOUNDS
IN BOTH CHLORINATED SAMPLES
Trapped volatile
compounds
Concentration of compounds, yg/1
Mixed primary/
secondary sludge Septage
Cyanogen chloride
Acetone
Dichloromethane
Chloroform
Toluene
Benzene
3-Methylbutanal
3-Methylpentanal
900
5
100
100
1
1
Not quantified
Not quantified
250
Not quantified
50
120
60
10
Chloroethane
1, 1-Di chloroethane
Methyl chloroform
Carbon tetrachloride
Di chl oroacetoni tri 1 e
n-Valeronitrile
Chlorotoluenes
Dichlorobenzenes
Hexane
5
60
40
2
60
50
170
260
Not quantified
14
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a. Column--!.53-M (5-ft) x 2-mm ID glass column, packed
with 3% OV-1 on 80/100 mesh Gas Chrom Q.
b. Flowrate--20 ml/min of helium.
c. Column temperature--3 min at 30 C, followed by programming
to 230 C at 8°/min for a total MS run time of 45 min.
d. Mass range--20 to 500 atomic mass units with 4-sec scans (i.e.,
integration time of 8 milliseconds/atomic mass unit).
e. Sensitivity--10~7 amp/volt.
f. Electron energy—70 eV.
g. Real time GC attenuation--3.
h. Data acquisition (the 45-min MS run) was started 1.0
min after injection to eliminate most of the solvent peak.
Compounds identified from EI/MS spectra during this phase of the project
were confirmed by running standards (when these were on-hand) or by reruns
using the CI/MS side of the Finnigan system. The reported concentrations are
accurate to only ±50%, and they are based on the assumption that 100% recovery
of each identified compound was realized,up to the point of GC/MS analysis.
Results
Tables 7, 8, and 9 show the values found for the individual, hexane-ether
extractable, non-volatile organic compounds in raw, dechlorinated, and
chlorinated samples, respectively.
DETERMINATION OF ADDITIONAL PARAMETERS FOR VENTURA CENTRATES TO PERMIT COST
CALCULATIONS FOR FILTRATION/CARBON ADSORPTION AS AN ADJUNCT TO PURIFAX
TREATMENT
Procedure
Each of the three Ventura centrates was analyzed for total dissolved solids,
total suspended solids, and total organic carbon by procedures described in
Standard Methods for the Examination of Water and Wastewater (5). A separate
portion of each centrate was then filtered through a 0.45-ym Millipore membrane,
and these filtrates were also analyzed for total organic carbon.
Results
The analytical values for these additional engineering parameters are
listed in Table 10.
15
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TABLE 7. CONCENTRATIONS OF HEXANE-ETHER EXTRACTABLE, NON-VOLATILE
ORGANIC COMPOUNDS IN BOTH RAW SAMPLES
Extracted compound
Di ethyl phthalate
Isobutyl phthalate
Di-n-butyl phthalate
Isopropyl phthalate
Di-(Z-ethylhexyl) phthalate
Farnesol
Chlorotoluene
3-hexanone
Fenchyl alcohol
Camphor
Myrcenol
Isoborneol
Terpinene-4-ol
Alpha-terpineol
Indole
3-Methylindole
1 ,1-Dibutoxye thane
Ethyl -p, p'-dichlorobenzilate
Concentration of
Mixed primary/
secondary sludge
2
80
40
2
10
2
-
-
-
-
-
-
-
-
-
-
-
-
Compound, yg/1
Septage
-
-
-
-
-
-
20
50
20
20
150
20
20
800
20
30
30
10
16
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TABLE 8. CONCENTRATIONS OF HEXANE-ETHER EXTRACTABLE, NON-VOLATILE
ORGANIC COMPOUNDS IN BOTH DECHLORINATED SAMPLES
Concentration of compound, yig/1
Mixed primary/
Extracted compound secondary sludge Septage
Pentachloroacetone 100 50
Chloroform 10
2,4,6-Trichlorophenol 2
Diethyl phthalate 2 5
Di-(2-ethylhexyl) phthalate 100
Dodecan-6,7-dione 2
3,7,7-Trimethyl-bicyclo-(3.1.1)-
2-heptanol 5
3-Hexanone Not,quantified
Acetone Not quantified
Chlorotoluene - 10
Isovaleric acid - 20
Dichlorobenzene - 20
Butyric acid - 30
(2-chloroethyl)-benzene - 30
Fenchyl alcohol - 50
3-Pentanol - 40
Isoborneol - 50
2-Ethylbutanoic acid - 5
Stearic acid - 150
1,1-Dibutoxyethane - 30
Toluene - Not quantified
Farnesol 5
17
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TABLE 9. CONCENTRATIONS OF HEXANE-ETHER EXTRACTABLE, NON-VOLATILE
ORGANIC COMPOUNDS IN BOTH CHLORINATED SAMPLES
Concentration of compound, yg/1
Mixed primary/
Extracted compound secondary sludge Septage
3-Methyl-3-pentanol 2
3-Hexanone 30
Pentachloroacetone 100 40
Chloroform 30
2,4,6-Trichlorophenol 2
Diethyl phthai ate 2
Isobutyl phthalate 80
Di-(n-butyl) phthalate 100
Di-(2-ethylhexyl) phthalate 2 10
Farnesol 5
2-Methyl-3-pentanol Tentative identification
Chlorotoluene - 10
Dichlorobenzene _ 10
(2-chloroethyl)-benzene - 20
Fenchyl alcohol - 30
Camphor - 30
3-Pentanol - 30
Iso-borneol - 30
n-Butyl-n-butyrate - 20
Stearic acid - 150
1,1-Dibutoxyethane - 10
Elemol - 10
Nerolidol isomer - 20
Di ethyl ether - 50
18
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TABLE 10. MISCELLANEOUS ENGINEERING PARAMETERS
FOR VENTURA CENTRATES
Concentration of parameter, mg/1
Centrate
parameter
Total dissolved solids
Total suspended solids
Total organic carbon
Raw
1,984
31.0
375
Dechlorinated
2,855
21.0
200
Chlorinated
3,158
21.0
190
Rerun of total organic carbon
after filtration through
0.45-yim millipore membranes 325 175 175
DISCUSSION
Relatively high percentages (1% by weight) of organic chlorine were
found in the Purifaxed solids phases. These chlorinated organics represent
a significant potential environmental hazard. If these solids phases are
disposed of as landfill material, and if subsequent long-term landfill
leaching occurs, at least some of these chlorinated organics are sure to
re-enter the environment with unknown health-effects risks. Unfortunately,
the present state-of-the-art of analytical chemistry does not permit identi-
fication of more than a small fraction of the individual chlorinated organic
constituents in Purifaxed solids phases. Such solids are extremely insoluble
in most organic solvents and therefore resist ordinary extraction methods.
Even extractive steam distillation of Purifaxed solids probably would permit
isolation and analysis of only small percentages of the chlorinated organics
actually present.
Evaluation of all the data on the Purifaxed liquid phases shows that
less than 1% of the total organic carbon in these phases were accounted for
by recovered chlorinated organic compounds. For example, the centrates from
Ventura contained approximately 200 mg/1 total organic carbon, and less than
1 mg/1 was identified as specific organic compounds. This strongly indicates
that recoveries of chlorinated organics before analysis were very low. This
result is readily understandable for the following reasons:
a. The microcoulometric titration values obtained for total,
hexane-ether extractable, non-volatile organic chlorine
in the liquid phases were in turn dependent on the relative
fractions of dissolved chlorinated organics extracted
(for subsequent analysis) by the solvent mixture employed for
this purpose. Had most of the chlorinated organics in the
19
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aqueous phases been highly polar in nature (that is, highly
water-soluble), then no simple extraction procedure could
have recovered more than a small fraction of the compounds
actually present.
b. When the hexane-ether extracts had to be concentrated from
180 ml down to 0.5-1.0 ml for microcoulometric and GC/MS
analyses, significant (but unknown) percentages of the
extracted chlorinated organics were lost because of volatility.
Some of these volatiles obviously would have been accounted
for during the independent determinations of helium-purgeable
constituents. On the other hand, much of the lost volatile
material would not have been thus accounted for, but instead
would have completely escaped detection.
Better recovery methods could no doubt be devised, but this would
require a major analytical undertaking.
20
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REFERENCES
1. Mashni, C. I. Effect of Purifax Chiorination Treatment on Septic
Tank Waste. Memorandum to Record, U.S. Environmental Protection
Agency, Cincinnati, Ohio, August 28, 1974. 4 pp.
2. Sawyer, C. N. Effects of Chiorination during Purifax System of Sludge
Treatment. Metcalf and Eddy, Inc., Engineers, Boston, Massachusetts,
April 2, 1971. 31 pp.
3. Bellar, T. A., and J. J. Lichtenberg. Determining Volatile Organics
at Microgram-per-Litre Levels by Gas Chromatography. J. Amer. Water
Works Assoc., 6602): 739-744, 1974.
4. Weicher, F. J. (ed.), and T. S. Ma. Microdetermination of Chlorine,
Bromine, or Iodine by the Closed Flask Method. In: Standard Methods
of Chemical Analysis. 6th Ed.,Vol. Two, Part A, pp. 389-392. D. Van
Nostrand Co., Princeton, New Jersey, 1963.
5. Standard Methods for the Examination of Water and Wastewater. 14th
Ed. American Public Health Association-American Water Works Association-
Water Pollution Control Federation, Washington, D.C., 1975.
21
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
REPORT NO.
EPA-600/2-78-020
3. RECIPIENT'S ACCESSION>NO.
TITLE AND SUBTITLE
Partial Characterization of Chlorinated Organics in
Superchlorinated Septages and Mixed Sludges
. REPORT DATE
March 1978 (Issuing Date)
6. PERFORMING ORGANIZATION CODE
. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
Robert H. Wise, Thomas A. Pressley, and
Barry M. Austern
. PERFORMING ORGANIZATION NAME AND ADDRESS
Municipal Environmental Research Laboratory—Cin.,OH
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
10. PROGRAM ELEMENT NO.
1BC611
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
Tnhnusp Rppnrt ?/in/77-fi/?a/77
Same as above
14. SPONSORINGiAGENcV CODE
EPA/600/14
15. SUPPLEMENTARY NOTES
Project Officer- Robert H. Wise 513/684-7627
16. ABSTRACT
The chlorinated organic materials produced by applying the proprietary Purifax process
to a septage and a mixed primary/secondary sludge were studied to assess the types,
amounts, and distribution of chlorinated organics present. Total organic chlorine
in the solids phases was determined by Schohiger-flask combustion. Concentrated
hexane-ether extracts of the liquid phases were also analyzed for total organic
chlorine by microcoulometric titration; these same extracts were then analyzed by
GC/MS for individual organic compounds. Helium-purgeable organics in the liquid
phases were also determined by GC/MS. Liquid phases from one Purifax installation
were analyzed for TOC, TDS, and TSS to furnish engineering cost data for applying
filtration/carbon adsorption as a Purifax-treatment adjunct.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. cos AT I Field/Group
*Sludge disposal
Sludge
Septic tanks
*Chlorination
*Chemical analysis
*Chemical Composition
*Purifax Process
*Superchlorination
Septages
Sludge treatment
Septage treatment
*Sludge analysis
*Septaae analysis
13B
18. DISTRIBUTION STATEMENT
RELEASE TO PUBLIC
19. SECURITY CLASS (ThisReport)
21. NO. OF PAGES
UNCLASSIFIED
I. SECURITY CLASS
30
20. SECURITY CLASS (Thispage)
IINriASSTFTFn
22. PRICE
EPA Form 2220-1 (9-73)
22
&U.S. GOVERNMENT PRINTING OFFICE 1978-757-140/6810 Region No. 5-11
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