Bench-scale Evaluation Of Zimpro's Wet Air Oxidation Process On Contaminated Sediments From The Grand Calumet River


        United States
        Environmental Protection
        Agency
Great Lakes
National Program Office
77 West Jackson Boulevard
Chicago, Illinois 60604
EPA 905-R94-007
May 1994
$EPA  Assessment and
        Remediation
        Of Contaminated Sediments
        (ARCS) Program


        BENCH SCALE EVALUATION OF
        ZIMPRO'S WET AIR OXIDATION
        PROCESS ON CONTAMINATED
        SEDIMENTS FROM THE GRAND
        CALUMET RIVER
                           United States Areas of Concern

                           ARCS Priority Areas of Concern

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                    Bench-Scale Evaluation of
              Zimpro's Wet Air Oxidation Process on
       Contaminated Sediments from the Grand Calumet River
                           Prepared by

                          Vic Engleman
             Science Applications International Corporation
                         San Diego, CA
                              for the
Assessment and Remediation of Contaminated Sediments (ARCS) Program
                U.S. Environmental Protection Agency
                 Great Lakes National Program Office
                          Chicago, Illinois

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                                       DISCLAIMER
       The information in this document has been funded wholly or in part by the U.S. Environmental
Protection Agency (EPA) under Contract No. 68-C8-0062, Work Assignment No. 3-52, to Science
Applications International Corporation (SAIC). It has been subjected to the Agency's peer and
administrative review and it has been approved for publication as an EPA document. Mention of trade
names or commercial products does not constitute endorsement or recommendation for use.
                                                   U.S. Environmental Protection Agency
                                                   Region 5, Library  (PL-12J)
                                                   77 West Jackson  Boulevarjd, 12th Floor
                                                   Chicago,  IL  60604-3590

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                                  ACKNOWLEDGEMENTS
This report was prepared by the Engineering/Technology Work Group (ETWG) as part of the Assess-
ment and Remediation of Contaminated Sediments (ARCS) program.  Dr. Stephen Yaksich, U.S. Army
Corps of Engineers (USACE) Buffalo District, was chairman of the Engineering/Technology Work
Group.

The ARCS Program was managed by the U.S. Environmental Protection Agency (USEPA), Great
Lakes National Program Office (GLNPO).  Mr. David Cowgill and Dr. Marc Tuchman of GLNPO were
the ARCS program managers.  Mr. Dennis Timberlake of the USEPA Risk Reduction Engineering
Laboratory was the technical project manager for this project. Mr. Stephen Garbaciak of USACE
Chicago District and GLNPO was the project coordinator.

This report was drafted through Contract No. 68-C8-0062, Work Assignment No. 3-52, to Science
Applications International Corporation (SAIC). Vic Engleman of SAIC was the principal author of the
report, with final editing and revisions made  by Mr. Garbaciak prior to publication.


This report should be cited as follows:

       U.S. Environmental Protection Agency.  1994. "Bench-Scale Evaluation of Zimpro's Wet Air
Oxidation Process on Contaminated Sediments from the Grand Calumet River," EPA 905-R94-007,
Great Lakes National Program Office, Chicago, IL.

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ABSTRACT
The Great Lakes National Program Office (GLNPO) leads efforts to carry out the provisions of
Section 118 of the Clean Water Act (CWA) and to fulfill U.S. obligations under the Great Lakes Water
Quality Agreement (GLWQA) with Canada. Under Section 118(c)(3) of the CWA, GLNPO was
responsible for undertaking a 5-year study and demonstration program for the remediation of contami-
nated sediments. GLNPO initiated an Assessment and Remediation of Contaminated Sediments
(ARCS) Program to carry out this responsibility. In order to develop a knowledge base from which
informed decisions may be made, demonstrations of sediment treatment technologies were conducted
as part of the ARCS Program. Bench-scale studies of the Zimpro Wet Air Oxidation Process, the
subject of this report, took place at Zimpro Passavant Environmental Systems, Inc. (Zimpro) in
Rothschild, Wl on August 27 to 29,1991. The primary objective for this effort was to determine the
feasibility and cost-effectiveness of the Zimpro wet air oxidation process for treating and removing
PAHs. The wet air oxidation process was not expected to treat PCBs, another known primary
contaminant group detected in the sediments.

The Zimpro Wet Air Oxidation Process was tested using a sediment obtained from the Grand
Calumet River. The concentrations of the contaminants of concern in the sediment were 11.9 mg/kg
PCBs and 266 mg/kg PAHs. The PCB and PAH concentrations of 8.5 and <2.84 mg/kg, respectively,
were found in the treated solids. This corresponds to PCB and PAH removals of 29 percent and >98.9
percent, respectively. Metals analyses were performed on the treated solids and untreated sediments.
The feed sediments and treated solids were analyzed for percent moisture, oil and grease, total organic
carbon (TOC), total volatile solids, and pH. Due to the sampling and analytical program for these tests,
it was not possible to calculate a mass balance as part of this study.
in

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                                   TABLE OF CONTENTS
Section                                                                                 Page

Disclaimer  	        i
Acknowledgements	        ii
Abstract	       Hi
List of Figures	        v
List of Tables	       vi

1.0    Executive Summary	        1

2.0    Introduction	        3

       2.1  Background	        4
       2.2 Sediment Descriptions  	        4
       2.3 Sediment Characterization  	        7
       2.4 Technology Description	        7

3.0    Treatability Study Approach	        9

       3.1  Test Objectives and Rationale	        9
       3.2 Experimental Design and Procedures  	       10
       3.3 Sampling and Analysis	       13

4.0    Results and Discussion	       15

       4.1  Summary of Phase I Results	       15
       4.2 Summary of Phase II  Results  	       15
       4.3 Summary of Vendor Cost Calculations	       21
       4.4 Quality Assurance/Quality Control 	       23

Appendix A -  Zimpro Reports for Phase I and Phase II 	       25
Appendix B -  Experimental Design  	       60
Appendix C - Quality Assurance Project Plan for GLNPO  	       75
Appendix D - Analytical Data  From Battelle  	      120
Appendix E -  Analysis of Quality Assurance/Quality Control  	      136
                                             IV

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                                    LIST OF FIGURES





Number



 1      ARCS Priority Areas of Concern	       5



 2      Grand Calumet River Sample Location	       6



 3      Wet Oxidation Flow Diagram for the Zimpro Wet Air Oxidation Process  	       8



 4      Conditions of Phase I Tests	      11



 5      Percent Destruction of PAH in Solids as a Function of Operating Conditions	      15

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                                     LIST OF TABLES


Number

 1      Summary of Total PAHs  	       1

 2      Summary of Total PCBs  	       1

 3      Characterization of Feed Sediments and Treated Solids  	       2

 4      Battelle Analysis - Characterization of Feed Sediments  	       7

 5      Wet Oxidation Feed  	      12

 6      SAIC's Analysis Schedule for Phase II Wet Air Oxidation of
       Grand Calumet River Sediments   	      14

 7      Zimpro Analyses	      15

 8      Feed and Treated Solids PAH Concentrations	      17

 9      Total PCBs	      17

10     Metal Concentrations in the Feed and Treated Solids  	      18

11      Reduction Percentages for Other Parameters	      19

12     PAH Concentrations in the Filtrate	      20

13     PCB Concentrations in the Filtrate	      20

14     Wet Oxidation Feed and Output   	      21

15     Time Required to Process Harbor Sediments as a Function of Unit Size	   21

16     System Design Parameters Selected by Zimpro  	   22

17     Capital Costs and Estimated Utility Requirements	   23

18     Annual Operating and Maintenance Costs for Treating Dredged Sediments  	   24
                                            VI

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1.0 EXECUTIVE SUMMARY
The Wet Air Oxidation Process was tested using sediments obtained from the Grand Calumet
River. The contaminants of concern in the sediments for these tests were polynuclear aromatic
hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). Samples of the feed material and the
treated solids produced using the Wet Air Oxidation Process were analyzed by Battelle Marine
Sciences Laboratory for residual PAH and PCB contamination. The data from these analyses are
presented in Tables 1 and 2.

Table 1. Summary of Total PAHs (mg/kg, dry)

Sample Feed • Treated Solids Destruction
Total PAHs 266 >2.84 >98.9
As these data demonstrate, the PAH destruction efficiency for the Grand Calumet River
sediment is about 99 percent. The data demonstrate the technical feasibility of the Zimpro Wet Air
Oxidation Process for treating and removing PAHs.

Feed material and treated solids were also analyzed for residual PCB concentrations. Table 2
outlines the analytical results obtained by Battelle.

Table 2. Summary of Total PCBs (mg/kg, dry)

Sample Feed Treated Solids Destruction
Total PCBs 11.9 8.5 29
The destruction efficiency for PCBs was only 29 percent, but the wet air oxidation process was
not expected to treat PCBs.

Metal analyses were performed on the treated solids and untreated sediments (see Section
4.2.1.3). The Battelle analyses demonstrate that the treatment process, as expected, had little effect on
metals removal from the sediments.

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The feed and treated solids were analyzed for percent moisture, oil and grease, TOO, total
volatile solids, and pH (see Table 3). The percent moisture decreased. Ninety percent of the oil and
grease was removed. TOC and treated volatile solids were reduced more than 50 percent. The pH
dropped to 6.5.
Table 3. Characterization of Feed Sediments and Treated Solids
(mg/kg, dry basis, unless otherwise specified)

Total PCBs
Total PAHs
Moisture, % (as received)
Oil & Grease
TOC, % weight
Total Volatile Solid, %
pH, S.U. (as received)
Feed Sediments
11.9
266
55.0
9890
19.3
15.0
7.67
Treated Solids
8.5
<2.84
43.3
951
9.3
7.3
6.51
Because of the nature in which the organic material is oxidized, the TOC analysis shown in
Table 11 was used to calculate the mass balance of the solids. The summation of the percent recovery
results indicates that 90 percent of the material charged to the reactor was recovered after treatment.
After correcting for the amount of sample oxidized during treatment and the amount known to be lost in
Run Number 4, about 94 percent of the original sample was accounted for. Since all the species
containing carbon and hydrogen in the sediment were not known and the organics were being oxidized
to carbon dioxide and water, it was not possible to conduct a more detailed mass balance.

Small vials of the residuals from the treatability test were retained and given to the EPA
Technical Project Manager for the GLNPO for "show" purposes. All quantities of the test products
(solids and filtrate) from the treatability test were sent to the analytical laboratory, Battelle, for analysis.
Due to the small quantities generated from the tests, none were retained and shipped to EPA for
possible further treatability studies.

Zimpro has estimated the capital costs of units to treat 10,000, 40,000, and 100,000 yd3 of
sediment at rates of 10 (60 TPD), 20 (120 TPD), and 40 gpm (240 TPD). These estimates are
approximately $4,500,000 for the 10 gpm unit; $5,600,000 for the 20 gpm unit; and $7,300,000 for the

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40 gpm unit. The sediment would be treated at a rate of 60 to 240 tons per day using 10 to 40 gpm
units operated on a 24 hour per day, 5 days per week, 50 weeks per year basis. The cost of treating
the sediment is estimated to be $329, $203, and $133/yd3 for the 10, 20, and 40 gpm units respective-
ly. This estimate by Zimpro includes capital and operating costs but does not account for the costs
associated with site excavation, civil work, applicable taxes, pre-screening needs, and overall site
management and disposition of the residuals.

2.0 INTRODUCTION
The Great Lakes National Program Office (GLNPO) leads efforts to carry out the provisions of
Section 118 of the Clean Water Act (CWA) and to fulfill U.S. obligations under the Great Lakes Water
Quality Agreement (GLWQA) with Canada. Under Section 118(c)(3) of the CWA, GLNPO is responsi-
ble for undertaking a 5-year study and demonstration program for the remediation of contaminated
sediments. Five areas were specified for priority consideration in locating and conducting demonstra-
tion projects: Saginaw River and Bay, Michigan; Sheboygan River, Wisconsin; Grand Calumet
River/Indiana Harbor Canal, Indiana; Ashtabula River, Ohio; and Buffalo River, New York. In response,
GLNPO initiated the Assessment and Remediation of Contaminated Sediments (ARCS) Program.

In order to develop a knowledge base from which informed decisions may be made, bench-
and pilot-scale demonstrations of sediment treatment technologies were conducted as part of the ARCS
Program. Information from remedial activities supervised by the U.S. Army Corps of Engineers and the
Superfund program wre also utilized. The Engineering/Technology (ET) Work Group was charged with
overseeing the development and application of the bench- and pilot-scale tests.

Science Applications International Corporation (SAIC) was contracted to provide technical
support to the ET Work Group. As part of this effort, SAIC was charged with conducting bench-scale
treatability studies on designated sediments to evaluate the removal of specific organic contaminants.
The bench-scale studies of the Zimpro Wet Air Oxidation Process, the subject of this report, took place
at Zimpro Passavant Environmental Systems, Inc. (Zimpro) in Rothschild, Wisconsin on August 27 to
29, 1991. The primary objective for this effort was to determine the feasibility and cost-effectiveness of
the Zimpro wet air oxidation process for treating and removing PAHs. The wet air oxidation process
was not expected to treat PCBs, another known primary contaminant group detected in the sediments.

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2.1 Background
SAIC and its subcontractors have conducted seven bench-scale tests for the ARCS Program on
four different sediments using four treatment technologies: Wet Air Oxidation (Zimpro Passavant),
B.E.S.T.™ Solvent Extraction Process (RCC), Thermal Desorption Technology (ReTeC), and Anaerobic
Thermal Process Technology (SoilTech). This report summarizes the approach used and results
obtained during treatability testing of the Zimpro Wet Air Oxidation Process. The sediments tested
using this technology were obtained from the Grand Calumet River.

The primary objective of this portion of the study was to determine the feasibility and cost-
effectiveness of the Zimpro Wet Air Oxidation Process for treating and removing PAHs from the Grand
Calumet River sediment. Based upon previous tests performed by Zimpro, the bench scale tests were
designed to provide data that closely simulate full-scale performance. Thus, data generated by these
tests may be used to estimate treatment costs for full-scale operations and to evaluate process
feasibility.

2.2 Sediment Descriptions
The sediments used during the treatability studies conducted by SAIC are typical of sediments
in the Great Lakes and their tributaries. These sediments were obtained from the Grand Calumet
River. They are representative of locations around the Great Lakes where future field demonstration
projects may be conducted. The primary contaminants in the Grand Calumet River sediments for the
purpose of this study are PCBs and PAHs.

2.2.1 Site Names and Locations for Each Sediment
GLNPO collected sediments for study from the following areas around the Great Lakes:
Saginaw River, Michigan; Sheboygan River, Wisconsin; Grand Calumet River/Indiana Harbor Canal,
Indiana; Ashtabula River, Ohio; and Buffalo River, New York. SAIC was contracted to treat four of the
sediments (from the Grand Calumet River, Buffalo River, Ashtabula River, and Saginaw River) using
four different technologies. Samples from the Grand Calumet River were treated using the Zimpro Wet
Air Oxidation Process. A map is provided in Figure 1 which shows the ARCS Priority Areas of
Concern. Specifics of the sample location for the Grand Calumet River are shown in Figure 2.

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C71
                                                   ARCS* PRIORITY
                                                 AREAS OF CONCERN
                          ARCS AREAS OF CONCERN
                            1. SHEBOYGAN RIVER
                   2. GRAND CALUMET RIVER / INDIANA HARBOR
                           3. SAGINAW RIVER / BAY
                            4. ASHTABULA RIVER
                              5. BUFFALO RIVER


          'Assessment and Remediation of Contaminated Sediments
      H
  0  M 100  IBO MO
     KlOMCTtm
US ENVnONMENTAl PROTECTION MENCV
GREAT LAKES NATDNAl PROORAU Off «
                             Rgure 1. ARCS Priority Areas of Concern

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en
                                                      Sediment sample point
                                               GRAND CALUMET RIVER
                                                                                M    IJ   t»
                                                                                 t  • ••-<	ImlUt
                                    Figure 2. Grand Calumet River Sample Location

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2.2.2 Sediment Acquisition and Homogenization
Prior to conducting the bench-scale treatability study using the wet air oxidation technology, the
GLNPO samples were homogenized and stored under refrigeration by the U.S. EPA Environmental
Research Laboratory in Duluth, MM.

Approximately 1 gallon of the homogenized sediments were sent to SAIC by the Duluth
laboratory. These sediment samples were then transferred by SAIC to Zimpro. Zimpro used these
samples in Phase I to perform a series of standard tests commonly performed to determine if the waste
sample was compatible with their process and to determine optimum testing conditions and procedures
for the Phase II treatability study. The sediments used during the treatability studies also originated
from this stock and were forwarded to Zimpro by SAIC.

2.3 Sediment Characterization
SAIC was responsible for the physical and chemical characterization of the raw sediment
samples used during the tests. Under SAIC direction, the sediments and their residuals were analyzed
by Battelle Marine Sciences Laboratory in Sequim, WA. Table 4 provides characterization data
pertaining to the sediments. The results from the raw sediment samples analyzed by Battelle are
shown in Table 4.

TABLE 4. Battelle Analysis - Characterization of Feed Sediments
(mg/kg, dry basis, unless specified)

Grand Calumet River
Total PCBs 13.1
Total PAHs 266
Moisture, % (as received) 55.0
Oil & Grease 9890
TOG, % weight 19.3
Total Volatile Solid, % 15.0
pH, S.U. (as received) 7.67

2.4 Technology Description
Wet air oxidation is a process in which organic or inorganic substances are oxidized in the
presence of water at elevated temperatures and pressures. The usual temperature range varies from

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approximately 350 to 600°F (175 to 320°C).  System pressures of 300 to well over 3000 psig are
required.  The reactor pressure is determined by the vapor pressure of the water and the amount of
excess oxidant used in the reactor. Compressed air or pure oxygen is the source of oxygen that
serves as the oxidizing agent in the wet air oxidation process. As the oxidation temperature is
increased, a larger portion of the organic compounds is oxidized. A basic flow diagram for the Zimpro
Wet Air Oxidation Process is shown in Figure 3.
      Q
      HIGH
   PRESSURE
     PUMP
            AIR COMPRESSOR
                                                                                            OXIDIZED
                                                                                            LIQUOR
               Figure 3.  Flow Diagram for the Zimpro Wet Air Oxidation Process.
                    (Source: Zimpro Passavant Environmental Systems, Inc.)
        In processing an aqueous waste, the waste stream containing the oxidizable material is first
 pumped to the system using a positive displacement, high pressure pump. The pressurized discharge
 from the high-pressure pump is combined with the air stream from the air compressor, forming a two-
 phase stream.
                                              8

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Next the air/waste stream passes through the feed/effluent heat exchanger, recovering heat
from the hot, oxidized effluent. The heated mixture is then routed through an auxiliary heat exchanger,
if needed. A vertical bubble-column is commonly used as the reactor to provide the required hydraulic
detention time to effect the desired reaction. The reactor contents are mixed by the action of the gas
phase rising through the liquid. As the gas phase rises and mixes with the liquid, oxygen is dissolved
into the liquid. The reactor is sized to allow the oxidation reactions to proceed to the desired level. The
desired reaction may range from a mild oxidation, which requires a few minutes, to total waste
destruction, which requires an hour or more of detention time.

The oxidized liquid, oxidation product gases, and spent air leave the reactor and are routed
through the shell side of the feed/effluent heat exchanger. A cooler can achieve additional cooling, if
necessary. The cooled reactor effluent is throttled through a pressure control valve into the process
separator where the reactor effluent is separated into a gaseous stream and a liquid stream. The
gaseous stream from the process separator is routed through an off-gas cooler. The liquid stream is
pumped beyond the treatment system's boundary limits. Further treatment of these oxidized liquids by
a biological system may be required prior to discharge into the final receiving system (POTW, river,
lake).

3.0 TREATABILITY STUDY APPROACH
3.1 Test Objectives and Rationale
SAIC has been contracted by the ARCS Program to test four technologies in removing organic
contaminants (PCBs and PAHs) from sediments typical of locations around the Great Lakes. This
treatability study has been done to determine the feasibility and cost-effectiveness of the Zimpro Wet
Air Oxidation Process for destroying PCBs and PAHs in Grand Calumet River sediments. In order to
accomplish this, this bench-scale test had the following objectives:
• To record observations and data to predict full-scale performance of the Zimpro Wet Air
Oxidation Process
• To take samples during the treatability tests and conduct analyses sufficient to evaluate
the solids and filtrate with respect to compounds of interest
• To calculate the destruction efficiency of target compounds
• To obtain treated solids (330 g dry basis) and filtrate for independent analysis.

Based upon previous tests performed by Zimpro, it is their experience that the data obtained
from the bench test simulate full-scale operation. Ultimately, this data may be used to estimate both

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the feasibility and treatment costs associated with a full-scale application of the technology. The ability
to evaluate process feasibility from these tests was also reported in the Zimpro reports on the Phase I
and Phase II tests (see Appendix A).

A two-phase approach was used during this study. During Phase I, SAIC sent a sample of the
untreated sediment to Zimpro. The sample underwent a series of initial tests in order to determine the
optimum conditions to be used during the actual treatability tests (Phase II). During Phase II, untreated
sediment from the Grand Calumet River was sent to Zimpro. Samples of raw (untreated) sediments
and the various end products generated during the treatability tests (Phase II) were obtained and
analyzed by SAIC. The data generated by SAIC were primarily used to determine treatment efficien-
cies. Vendor-generated data are reported and commented on when available.

This study is only one part of a much larger program and is not intended to evaluate the
treatment of the sediments completely. In order to ensure that the data obtained from this study can be
objectively compared with data generated from the other studies performed in support of the ARCS
Program, Battelle was subcontracted to perform all analyses for the different treatability studies
performed by SAIC (seven treatability studies utilizing four technologies on four sediments). Assuming
that the appropriate volumes of sediment and residuals were available, the same set of analyses
described in Table 6 were applied during the characterization of each raw sediment and the end
products from the different treatability tests. In addition, representatives from SAIC observed all Phase
II treatability tests.

3.2 Experimental Design and Procedures
3.2.1 Phase I
Phase I was designed to allow Zimpro to explore a range of variables in order to set test
parameters which would optimize the performance of the wet air oxidation technology for the bench-
scale tests (Phase II). In order to accomplish this, a one-gallon sample of the Grand Calumet River
sediment was sent to Zimpro by SAIC prior to bench-scale testing.

A factorial-design wet oxidation test with three levels of each variable was performed on the
sediment to give an indication of the importance of the two experimental variables: residence time and
oxidation temperature. Tests were run at the conditions shown in Figure 4.
10

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320
300
280
X

X
30 60 90
OXIDATION TIME (min)

Figure 4. Conditions of Phase i Tests.

At 280°C typical test pressures were 2100 to 2200 psig; at 300°C typical test pressures were 2400
to 2500 psig; at 320°C typical test pressures were 2800 to 3000 psig. The Phase I wet air oxidation tests
were performed in stainless steel laboratory autoclaves, each having a capacity of 0.75 L. The as-received
waste sample was diluted with 3 parts distilled water to 1 part sediment (by volume) to reduce the total
solids concentration and viscosity of the waste. The solids and water were slurried and put into the
autoclaves with sufficient compressed air to result in an excess of oxygen following oxidation. The charged
autoclaves were then placed in a heater/shaker mechanism, heated to the desired temperature, and held
for the specified reaction time. Immediately following oxidation, the autoclaves were cooled to room
temperature and depressurized.

Materials screening tests were also performed on the prepared sediment slurry. The tests were
performed at 280°C for 100 hours. The following materials were tested, and all were found to have no
localized corrosion and a general corrosion rate of < 1.0 MPY: 316-L stainless, Alloy 20cb-3, Alloy 625,
Hastelloy C-276, and Titanium Grade 2. The results of these materials tests indicate that 316-L stainless
steel would perform acceptably and be the most economical material of construction for a full-scale wet air
oxidation system. A longer-term materials of construction test is recommended once the final wet air
oxidation design conditions are determined.

3.2.2 Phase II
The experimental design for Phase II of the treatability program is presented in Appendix B and
is summarized in this section.

The Phase II wet air oxidation tests were performed in titanium-stirred laboratory autoclaves, each
having a capacity of 3.78 L. The autoclaves were equipped with a magnetic stirring device to help the
11

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oxygen diffuse into the liquid and keep the solids in suspension. The stirrer remained on throughout the
oxidation.

The as-received feed samples were removed from their jars and placed in a stainless-steel mixing
bowl. A continuous mixer was used to stir the samples to obtain homogeneity. A glass beaker was used
to remove aliquots and samples from the bowl, with the stirrer still in operation. The feed material was
divided into seven portions for testing and two samples for the analysis of the raw feed. Separate stirred
autoclave oxidations were performed using six of the seven samples. The samples were diluted, using
HPLC grade water, to produce an autoclave feed sample with a suspended solids concentration of
approximately 10 percent. Ten percent suspended solids was used to simulate the 10 to 20 percent
concentrations that would be used in a commercial unit to allow the sediment to be pumped at pressure.
This does not mean that all the additional water needs to be supplied as feed water; some can be recycled
from the filtrate after treatment. Based on the Phase I test, a reactor temperature of 280°C and a hydraulic
detention time of 90 minutes was selected for the Phase II tests. These conditions were selected to
provide a balance between PAH destruction and process economics. Table 5 presents information on the
feed samples charged to the stirred autoclave and the volume discharged.

Table 5. Wet Oxidation Feed
Run Number
1
2
3
4
5
6
Sample Number
US02
US04
US01
US03
US05
US06
Sample
Sediment
253
250
225
225
128
126
Charged
Water
597
601
626
625
627
625
The autoclaves were charged with the sediment slurry and sufficient compressed air to result in
excess oxygen remaining following oxidation. The charged autoclaves were then heated to the desired
oxidation temperature by electrical heating bands and held at that temperature for the specified reaction
time. Immediately following the oxidation, the autoclaves were cooled to room temperature by internal
water cooling coils and then depressurized.

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3.3 Sampling and Analysis
The Quality Assurance Project Plan is provided in Appendix C.
3.3.1 Sampling
At the beginning of the Phase II Treatability test, SAIC personnel observing Phase II packed and
shipped a sample of the untreated Grand Calumet River sediment to SAIC's subcontract laboratory,
Battelle, in accordance with written detailed instructions supplied to the SAIC on-site representative. The
material was thoroughly mixed to achieve homogeneity of the solids and liquids in order to obtain a sample
representative of the material treated in the Zimpro Wet Air Oxidation Process. There was no feed
preparation other than mixing prior to sampling or testing.

After each of the six wet oxidation tests was complete, samples of the final filtrate and solid
residuals were collected by SAIC for EPA and Zimpro. Samples from the six tests were composited to a
single sample for analysis. The filtrate and solids were composited separately. As specified in the Quality
Assurance Project Plan (QAPP) a minimum of 300 g dry basis of solid material was required in order for
Battelle to be able to complete the necessary analyses of that material. The net weight of sample collected
for Battelle was 394 g. Zimpro was provided with approximately 30 g of sample and two show vials with
a small amount of solid material were collected for GLNPO.

3.3.2 Analysis
The analyses specified in Table 6 were conducted by SAIC's subcontracted laboratory, Battelle,
on the sediments and the process by-products from Phase II. Zimpro conducted analyses for COD, BOD,
total solids and ash, and pH. Battelle's data was used for the results presented in this report. Zimpro's
data, where possible, is discussed to facilitate interpretation of the results of the treatability test.

3.3.2.1 Battelle Analyses
Following the Phase II treatability test, Battelle conducted analyses on the raw sediment and the
end products. The number of analyses conducted on these sediments and their residuals are listed in
Table 6. Descriptions of the analytical methods employed can be found in the QA Section of this report.

3.3.2.2 Zimpro Analyses
Zimpro analyzed the treated solids and filtrate for COD, BOD, total ash and solids, and pH.
Table 7 shows the analyses performed by Zimpro. Details on the analytical methods used by Zimpro are
presented in Appendix A.
13

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       Table 6. SAIC's Analysis Schedule For the Phase II Wet Air Oxidation of Grand Calumet River Sediments
Parameters
Total Solids
(Moisture)
Volatile Solids
O&G
Metals
PCBs
PAHs
TOC
Total Cyanide
Total Phosphorus
PH
BOD
Total Suspended
Solids
Conductivity
QC Sample
and
Method Blank
(1)
YES
(1)
YES
(1)
YES
(0)
YES
(0)
YES
(0)
YRS
(0)
YES
(0)
YES
(«)
YES
(0)
_ YES
NA
NA
NA
Untreated
Sediment
(1)
G
(1)
G
0)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G



MS



(1)
G
(1)
G
(1)
G
NA
NA
NA




Tripli-
cate
(2)
G
(2)
G
(2)
G
(2)
G
(2)
G
(2)
1 G
NA
NA
NA
NA



Treated
Solids
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G
(1)
G



MS



(1)
G
(1)
G
0)
G
NA
NA
NA




MSD




(1)
G
(1)
G
NA






Tripli-
cate
(2)
G
(2)
G
(2)
G
(2)


-
NA
NA
NA



Water

NA*
NA
NA
(1)
G
(1)
G
NA
NA
NA
NA
NA
NA
NA
MS



NA
(1)
G
(1)
G
NA
NA
NA




MSD



: .........
(1)
G
(1)
G







Tripli-
cate

NA
NA
NA
;:xx .-. • •••:
.'• " • ;.;•: :

NA
NA
NA
NA
NA
NA
NA
Oil




NA
NA







MS




NA
NA

••' 	 ;••





Tripli-
cate




NA
NA







* Not Analyzed
(1) = Number of Analyses
G = Grand Calumet River
MS = Matrix Spike
MSD = Matrix Spike Duplicate

-------
Table 7. Zimpro Analyses
Matrix Sample
Treated Solids
Filtrate
COD
yes
yes
BOD5
no
yes
Total
Solids
yes
yes
Total
Ash
yes
yes
PH
no
yes
4.0 RESULTS AND DISCUSSION
4.1 Summary of Phase I Results
The principal objectives for the Phase I study were to ascertain the degree of destruction of PAHs
and COD found in the sediment sludge. In addition, a preliminary materials of construction evaluation was
conducted. Oxidations were performed in laboratory autoclaves at temperatures of 280, 300, and 320°C.
The residence time for the oxidations ranged from 30 to 90 minutes. The conditions tested are illustrated
in Figure 5, which indicates the destruction efficiency for PAHs. The Phase I study concluded that the PAH
destruction was in the range of 94 to 99 percent and the COD destruction was in the range of 45 to 70
percent. The condition selected by Zimpro as optimum was a reactor temperature of 280°C and a hydraulic
detention time of 90 minutes.
320
300
280
96.2%

97.3%

94.2%

98.8%

95.7%
30 60 90
OXIDATION TIME (min)

Figure 5. Percent Destruction of PAH in Solids as a Function of Operating Conditions.
4.2 Summary of Phase II Results
The concentrations of PAHs, PCBs, metals, total solids, volatile solids, and oil and grease present
in the untreated sediments and treated solids were measured in this study. The following sections briefly
address the analytical results obtained for contaminant concentrations present in the raw sediments and
15

-------
the process residuals (i.e., treated solids and filtrate). The analytical data received from Battelle can be
found in Appendix D.

Individual PAH compounds, PCB Aroclors, and metals were quantitated during sample analyses.
In order to determine overall destruction efficiencies for each class, it was necessary to sum these
individual results. In instances where all reported results were less than the analytical detection limits, total
concentrations are reported as less than the sum of the individual detection limits. Where one or more
individual components are above detection limits, total concentrations are reported as less than the sum
of the detected components plus the sum of the detection limits of the undetected components.

4.2.1 Sediments/Treated Solids
4.2.1.1 PAHs
Feed material and treated solids were analyzed for PAHs. As shown in Table 8, total PAH
concentrations of less than 2.84 mg/kg were found in the solids produced by treating the Grand Calumet
River sediments. These values correspond to a destruction efficiency of greater than 98.9 percent. Some
of the organics in the untreated sediment were destroyed during treatment, thereby reducing the volume
of the sediments. Based on results for TOC (shown in Table 11), it appears that about 10 percent by
weight of the sediment was destroyed by wet oxidation. Since the mass balance (Section 4.2.3) indicates
that over 90 percent of the material charged to the reactor was recovered, the calculation for PAH
destruction was based on the PAH concentrations in the solids before and after treatment.

4.2.1.2 PCBs
Samples of the feed material and the treated solids produced using the Zimpro Wet Air Oxidation
Process were analyzed for PCB contamination. The data from these analyses are presented in Table 9.

A PCB concentration of 8.5 mg/kg was found in the treated solids generated from the Grand
Calumet River sediment. This corresponds to a PCB destruction efficiency of 29 percent. However, the
Wet Air Oxidation Process was not expected to treat PCBs since previous tests have shown that PCBs are
too refractory for effective treatment by wet oxidation under these test conditions.
16

-------
      Table 8. Feed and Treated Solids PAH Concentrations
                         (mg/kg, dry basis)
Contaminant
Naphthalene
Acenaphthylene
Acenaphthene
Fluorene
Phenanthrene
Anthracene
Fluoranthene
Pyrene
Benzo(a) anthracene
Chrysene
Benzo(b)fluoranthene
Benzo(k)fluoranthene
Benzo(a)pyrene
lndeno(1 ,2,3-cd)pyrene
Dibenzo(a,h)anthracene
Benzo(g,h,i)perylene
Total PAH
1 Average of three analyses
2 Single analysis
Feed1
4.2
3.1
4.4
4.9
15.9
6.4
33.3
33.0
21.4
29.4
25.0
16.3
27.6
19.5
7.1
14.4
265.9

Grand Calumet
Treated2
0.03
<0.15
<0.02
<0.02
0.17
0.04
0.11
0.18
0.24
0.84
0.29
<0.004
0.27
0.12
0.17
0.19
<2.84

River
% Destruction
99.3
>95.2
>99.5
>99.6
98.9
99.4
99.7
99.5
98.9
97.1
98.8
>99.9
99.0
99.4
97.6
98.7
>98.9

Table 9. Total PCBs
(mg/kg, dry)
Sample Feed2
Total PCBs1 11.9


Treated Solids3
8.5
%
Destruction
29
1 Identified as Aroclors 1248 and 1254
2 Average of three analyses
3 Single analysis
                                 17

-------
4.2.1.3  Total Metals
       The data in Table 10 highlight the results for the metal contaminants present in the untreated feed
and the treated solids.  As demonstrated by the fact the metals concentrations are higher in the treated
solid than in the untreated sediment, the Wet Air Oxidation Process does not effectively remove metals.
The increase is probably related to the 10 percent volume reduction for the subject sediment achieved from
the destruction of the organics by the Wet Air Oxidation Process.

                TABLE 10. Metal Concentrations in the Feed and Treated Solids
                                         (mg/kg, dry)
Contaminant
Arsenic
Barium
Cadmium
Chromium
Copper
Iron
Lead
Manganese
Mercury
Nickel
Selenium
Silver
Zinc
Feed
27.6
283
7.7
1075
254
173,000
746
1910
1.40
115
5.4
4.8
3030
Treated Solids
29.1
368
13.0
1437
350
227,000
1095
2677
2.26
138
6.7
6.9
4290
4.2.1.4  Other Analyses
       The feed sediments and treated solids were analyzed for percent moisture, oil and grease, TOC,
total volatile solids, and pH as shown in Table 11.  The oil and grease was reduced by 90 percent. The
TOC was initially 19.3 percent by weight and was reduced to 9.3 percent by weight, including a 10 percent
weight loss caused by destruction of the organics.  The pH was reduced from about 7.5 to 6.5 in the
treated solids.
                                              18

-------
Table 11. Reduction Percentages for Other Parameters
(mg/kg, dry basis, unless specified)
Contaminant
Total PAHs
Total PCBs
Moisture, %
(as received)
Oil & Grease
TOC, % weight
Total Volatile Solids, %
pH, S.U. (as received)
Feed
266
11.9
55.0
9890
19.3
15.0
7.67
Percent
Treated Solids Reduction or Destruction
<2.84
8.5
43.3
951
9.3
7.3
6.51
>98.9
29

90
52
51

4.2.2 Filtrate
The concentrations of PAHs and PCBs in the filtrate from the wet oxidation reactor can be found
in Tables 12 and 13. Individual PAH concentrations were mainly below the detection limits. The results
indicate that the wet oxidation process destroys the PAHs and some of the PCBs, but does not extract
large amounts into the water.

4.2.3 Mass Balance Calculations
Wet air oxidation is a process in which organic material is oxidized in the presence of water.
Hydrocarbons are oxidized to water and carbon dioxide, while chlorine reacts to form HCI. Because of the
interaction between the organic material and water, the sum of the solids and the water is used for the
mass balance. Table 11 indicates that the TOC in the solids (Dry Basis) is reduced from 19.3 percent to
9.3 percent. This amounts to an 11 percent weight loss for the dry sediment, which is equivalent to a 5
percent weight loss for the wet sediment. This weight loss from reaction amounts to about 1.5 percent of
the total weight of sediment and water charged to the reactor. An additional 100 to 150 g of sample were
lost in a transfer procedure in Run Number 4. This represents 2 to 3 percent of the total mass of the six
test runs. The summation of the percent recovery results shown in Table 14 indicates that 90 percent of
the material charged to the reactor was recovered after treatment. Correcting for the amount of sample
oxidized during treatment, and the amount known to be lost in Run Number 4, about 94 percent of the
original sample was accounted for. Since all the species containing carbon and hydrogen in the sediment
were not known and the organics were being oxidized to carbon dioxide and water, it is not possible to
conduct a more detailed mass balance.

-------
 Table 12. PAH Concentrations in the Filtrate (ug/L)

  Contaminant                          Filtrate
  Naphthalene                           0.96
  Acenaphthylene                       <0.15
  Acenaphthene                        <0.22
  Fluorene                             <0.19
  Phenanthrene                         1.04
  Anthracene                           <0.14
  Fluoranthene                          0.16
  Pyrene                                0.14
  Benzo(a) anthracene                   <0.10
  Chrysene                             <0.10
  Benzo(b)fluoranthene                  <0.07
  Benzo(k)fluoranthene                  <0.06
  Benzo(a)pyrene                       <0.08
  lndeno(1,2,3-cd)pyrene                <0.07
  Dibenzo(a,h)anthracene                <0.09
  Benzo(g,h,i)perylene                   <0.07
  Total PAHs                           <3.64
  Table 13.  PCB Concentrations in the Filtrate (ug/L)

Contaminant                         Filtrate
Aroclor 1242                          <0.2
Aroclor 1248                          <0.2
Aroclor 1254                          <0.1
Aroclor 1260                          <0.1
                         20

-------
Table 14. Wet Oxidation Feed and Output (grams)
Run Number
1
2
3
43
5
6
Sample
Number1
US02
US04
US01
US03
US05
US06
Sample Charged
Sediment Water
253
250
225
225
128
126
597
601
626
625
627
625
Sample Removed
Solids
88
84
108
66
51
43
Filtrate
682
685
703
545
615
657
Percent
Recovered2
91
90
95
84
88
93
1 Note that Table 1 in Appendix A, Phase II is based on Sample Number instead of Run Number.
2 Before accounting for weight loss by oxidation. Average of all six percentages is 90 percent.
3 Pump tubing leaked causing small loss of sample (100-150 ml). Sample was considered valid since the loss was small and
sample appeared representative.

4.3 Summary of Vendor Cost Calculations
Zimpro and SAIC mutually developed three scenarios for the full-scale wet air oxidation of the
Grand Calumet River sediments. The three scenarios involve the treatment of 10,000,40,000, and 100,000
yd3 of all sediments; all at 40 percent solids. The Wet Air Oxidation Process designed can handle
sediments at a solids concentration of 10 percent; therefore a 3 to 1 dilution, using water from the harbor
that is being dredged, would be required. Wet air oxidation units of 10, 20 and 40 gallons per minute
capacity would handle these volumes of sediment as shown in Table 15. The design parameters for the
proposed systems are presented in Table 16.