United States
Environmental Protection
Agency
Office of Research and
Development
Washington DC 20460
EPA/540/AR-93/520
May 1994
CAV-OX® Cavitation
Oxidation Process Magnum
Water Technology, Inc.
Applications Analysis Report
SUPERFUNO INNOVATIVE
TECHNOLOGY EVALUATION
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o
do
EPA/540/AR-93/520
May 1994
CAV-OX® Cavitation Oxidation Process
Magnum Water Technology, Inc
Applications Analysis Report
U.S. Environmental P-Action Agency
Region 5, Library (?L--2fi
77 West Jackson Boulevard, 12th Floor
Chicago, IL 60604-3590
Risk Reduction Engineering Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
Printed on Recycled Paper
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Notice
The information in this document has been prepared for the U.S. Environmental Protection Agency's
(EPA) Superfund Innovative Technology Evaluation Program under Contract No. 68-CO-0047. This
document has been subjected to EPA's peer and administrative reviews, and approved for publication as
an EPA document. Mention of trade names or commercial products does not constitute an endorsement
or recommendation for use.
11
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Foreword
The Superfund Innovative Technology Evaluation (SITE) Program was authorized in the 1986
Superfund Amendments and Reauthorization Act. The program is a joint effort between the
U.S. Environmental Protection Agency's (EPA) Office of Research and Development and Office of Solid
Waste and Emergency Response. The purpose of the program is to assist the development of innovative
hazardous waste treatment technologies, especially those that offer permanent remedies for contamination
commonly found at Superfund and other hazardous waste sites. The SITE Program evaluates new
treatment methods through technology demonstrations designed to provide engineering and cost data for
selected technologies.
A field demonstration was conducted under the SITE Program to evaluate the ability of the CAV-OX®
process to treat groundwater contaminated with volatile organic compounds. The demonstration took place
at Edwards Air Force Base Site 16, California. The demonstration was directed toward obtaining
information on the performance and cost of the technology and assessing its use at this and other hazardous
waste sites. Documentation consists of a technology evaluation report, which describes field activities and
laboratory results, and this applications analysis report, which interprets the data and discusses the potential
applicability of the technology.
A limited number of copies of this report will be available at no charge from EPA's Center for
Environmental Research Information, 26 West Martin Luther King Drive, Cincinnati, Ohio 45268, (513)
569-7562. Requests for copies should include the EPA document number found on the report's cover.
When this supply is exhausted, additional copies can be purchased from the National Technical Information
Service, Ravensworth Building, Springfield, Virginia 22161, (703) 487-4600. Reference copies will be
available at EPA libraries in the Hazardous Waste Collection.
E. Timothy Oppelt, Director
Risk Reduction Engineering Laboratory
ill
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Abstract
This report evaluates the ability of the CAV-OX® cavitation oxidation process to remove volatile
organic compounds (VOC) present in aqueous wastes. This report also presents economic data based on
the Superfund Innovative Technology Evaluation (SITE) Program demonstration and nine case studies.
The patented CAV-OX® process was developed by Magnum Water Technology (Magnum) to destroy
organic contaminants in water. The process uses hydrodynamic cavitation, ultraviolet (UV) radiation, and
hydrogen peroxide to oxidize organic compounds in water at or below milligrams-per-liter levels. This
treatment technology produces no air emissions and generates no sludge or spent media that require further
processing, handling, or disposal. Ideally, the end products are water, carbon dioxide, halides, and in
some cases, organic acids. The process uses mercury vapor lamps to generate UV radiation. The principal
oxidants in the process, hydroxyl and hydroperoxyl radicals, are produced by hydrodynamic cavitation and
direct photolysis of hydrogen peroxide at UV wavelengths.
The CAV-OX® process was demonstrated under the SITE Program at Edwards Air Force Base
(Edwards) Site 16, California. Over a 4-week period in March 1993, about 8,500 gallons of VOC-
contaminated groundwater was treated with both the CAV-OX® I low-energy process and the CAV-OX®
II high-energy process. For the SITE demonstration, some configurations of the CAV-OX® process
achieved trichloroethene (TCE) and benzene removal efficiencies of greater than 99.9 percent. Likewise,
some configurations of the CAV-OX® process met State of California drinking water action levels and
federal drinking water maximum contaminant levels for TCE and benzene at the 95 percent confidence
level. Influent concentrations of TCE and benzene ranged from 1,500 to 2,000 and 250 to 500 micrograms
per liter, respectively. No scaling was observed on any of the UV tubes. Magnum reports that scaling
does not occur in the CAV-OX® process.
Potential sites for applying this technology include Superfund and other hazardous waste sites that have
groundwater or aqueous wastes contaminated with organic compounds. Economic data indicate that
groundwater remediation costs could range from about $13 to $31 per 1,000 gallons, depending on
individual site characteristics. Of these costs, CAV-OX® process direct treatment costs could range from
about $5 to $11 per 1,000 gallons.
The document includes three appendixes. Appendix A describes Magnum's experience in developing
and applying the principles of hydrodynamic cavitation in combination with advanced oxidation for the
treatment of industrial effluents and groundwater. Appendix B briefly describes Edwards Site 16 and
summarizes the SITE demonstration activities and demonstration results. Appendix C summarizes nine
case studies provided by Magnum.
IV
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Contents
Section Page
Notice ii
Foreword iii
Abstract iv
Contents v
Figures ix
Tables ix
Abbreviations, Acronyms, and Symbols xi
Conversion Factors xiii
Acknowledgements xiv
1. Executive Summary 1
Overview of the SITE Demonstration 2
Results from the SITE Demonstration 2
Vendor-Provided Results from Case Studies 3
Waste Applicability 3
Economics 3
2. Introduction 5
Purpose, History, and Goals of the SITE Program 5
Documentation of the SITE Demonstration Results 6
Purpose of the Applications Analysis Report 6
Technology Description 6
Treatment Technology 6
Process Components and Function 8
Innovative Features of the Technology 8
Key Contacts 10
3. Technology Applications Analysis 11
Effectiveness of the CAV-OX® Process 11
Results of the SITE Demonstration 11
Results of Other Case Studies 12
Factors Influencing Performance 12
Influent Characteristics 12
Operating Parameters 13
Maintenance Requirements 13
Site Characteristics 14
Support Systems 14
Site Access 15
Climate 15
Utilities 15
Services and Supplies 15
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Material Handling Requirements 15
Pretreatment Materials 15
Treated Water 16
Personnel Requirements 16
Potential Community Exposures 16
Potential Regulatory Requirements 16
Comprehensive Environmental Response, Compensation, and Liability Act 16
Resource Conservation and Recovery Act 18
Clean Water Act 18
Safe Drinking Water Act 18
Toxic Substances Control Act 19
Mixed Waste Regulations 19
Federal Insecticide, Fungicide, and Rodenticide Act 19
Occupational Safety and Health Administration 19
4. Economic Analysis 21
Basis of Economic Analysis 21
Cost Categories 24
Site Preparation Costs 24
Permitting and Regulatory Requirements Costs 25
Capital Equipment Costs 25
Startup Costs 26
Labor Costs 26
Consumables and Supplies Costs 26
Utilities Costs 27
Effluent Treatment and Disposal Costs 27
Residuals and Waste Shipping and Handling Costs 27
Analytical Services Costs 27
Maintenance and Modifications Costs 28
Demobilization Costs 28
References 28
Appendix A - Vendor's Claims for the Technology 29
Introduction 29
Hydrodynamic Cavitation 29
Physical Process 29
Chemical Process 30
Technology Description 30
Contaminants Treated by the CAV-OX® Process 31
Treatment By-Products 31
Operating Modes 31
Applications 32
Treatment Capacity 32
Pretreatment Requirements 32
Transportation to Site 32
Installation 32
Power Requirements 32
Installation Time 32
Permanent Installation 32
Portable Units 33
Hydrogen Peroxide Supply 33
Personnel Requirements 33
Comparison with Other Advanced Oxidation Technologies 33
VI
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Technical Data and Cost Comparisons 33
SITE Demonstration Results 33
Cavitation Chamber Only 33
Procedure 39
Results 39
Economic Analysis 39
References 39
Appendix B - SITE Demonstration Results 43
Site Description 43
Site Contamination Characteristics 46
Review of SITE Demonstration 46
Site Preparation 46
Major Support Equipment 46
On-Site Support Services 46
Utilities 46
Technology Demonstration 46
Operational and Equipment Problems 46
Health and Safety Considerations 48
Site Demobilization 48
Experimental Design 48
Testing Approach 48
Sampling and Analytical Procedures 50
Review of Treatment Results 50
Summary of Results for Critical Parameters 52
Summary of Results for Noncritical Parameters 52
Hydrogen Peroxide Effects 52
pH Effects 57
Vendor-Selected Conditions 57
Additional Noncritical Parameters 60
Conclusions 60
References 61
Appendix C - Case Studies 63
Introduction 63
CASE STUDY C-l: Wood Treating Superfund Site, Pensacola, Florida 64
Introduction 64
Equipment 64
Methodology 65
Results 65
CASE STUDY C-2: Chevron Service Station, Long Beach, California 65
Introduction 65
Equipment 65
Methodology 65
Operations 67
Results 67
CASE STUDY C-3: Presidio Army Base, San Francisco, California 67
Introduction 67
Equipment 67
Results 67
CASE STUDY C-4: Chemical Plant, East Coast U.S 67
Introduction 67
Equipment 68
Methodology 68
Vll
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Results 68
CASE STUDY C-5: Mannesmann Anlagenbau, Salzburg, Austria 68
Introduction 68
Equipment 68
Methodology 68
Results 68
CASE STUDY C-6: Steel Mill, South Korea 68
Introduction 68
Equipment 68
Methodology 69
Results 69
Cyanide Tests 69
Phenol Tests 69
Combined Cyanide and Phenol Tests 69
CASE STUDY C-7: Perdue Farms, Bridgewater, Virginia 69
Introduction 69
Equipment 71
Methodology 71
Results 71
CASE STUDY C-8: Southern California Edision, Los Angeles, California 71
Introduction 71
Equipment 71
Methodology 71
Results 72
CASE STUDY C-9: Corporacion Mexicana de Investigacion en Materials,
S.A. de.C.V. (CMIMSA) 72
Introduction 72
Equipment 72
Methodology 72
Results 72
Vlll
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Figures
Pag
1 The CAV-OX® Process as Demonstrated 9
A-l CAV-OX® Process Used at Edwards Air Force Base 34
B-l Edwards Site Location 44
B-2 Site 16 Layout 45
B-3 CAV-OX® Process Sample and Measurement Locations 47
B-4 Influent Concentrations - Primary Contaminants 51
B-5 Influent Concentrations - Secondary Contaminants 51
B-6 Trichloroethene Removal Efficiency Comparison 55
B-7 Benzene Removal Efficiency Comparison 56
B-8 Comparison of 95 Percent UCLs for Effluent VOC Concentrations
with Demonstration Target Levels (Run 12) 57
B-9 CAV-OX® I Flow Variations on Trichloroethene Removals 58
B-10 CAV-OX* I Flow Variations on Benzene Removals 58
B-ll CAV-OX® II Flow Variations on Trichloroethene Removals 59
B-l2 CAV-OX® II Flow Variations on Benzene Removals 59
C-l Photograph of CAV-OX® Process 66
Tables
Table Pag
1 CAV-OX® Process Cost Summary 3
2 Comparison of Technologies for Treating VOCs in Water 10
3 Regulations Summary 17
4 Costs Associated with the CAV-OX® I Low-Energy Process 22
5 Costs Associated with the CAV-OX® II High-Energy Process 23
A-l Desirable Influent Characteristics 32
A-2 Mobile Laboratory Results for Samples Collected 3/24/93 35
A-3 Mobile Laboratory Results for Samples Collected 3/24/93 35
A-4 Mobile Laboratory Results for Samples Collected 3/24/93 36
A-5 Mobile Laboratory Results for Samples Collected 3/24/93 36
A-6 Mobile Laboratory Results for Samples Collected 3/25/93 37
A-7 Mobile Laboratory Results for Samples Collected 3/26/93 38
A-8 Developer-Generated SITE Demonstration Results (Percent Reduction),
CAV-OX® Cavitation Chamber Only 40
A-9 Economic Comparisons for Groundwater Treatment Process 41
A-10 Economic Comparison Between a Carbon Adsorption System and
CAV-OX® I Low-Energy Process 41
B-l Experimental Conditions 49
IX
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B-2 Target Levels for Critical Analytes in Effluent Samples 50
B-3 Contaminant Removal 53
B-4 Contaminant Removal Efficiency 54
C-l Case Study Summary 64
C-2 Groundwater Sampling Results, August 20, 1990 67
C-3 Cyanide Removals 70
C-4 Phenol Removals 70
C-5 Combined Cyanide/Phenol Removals 70
C-6 Salmonella Study Results 71
C-7 Phenol Removal Comparison 72
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Abbreviations, Acronyms, and Symbols
AAR Applications Analysis Report
ACL Alternate concentration limit
AEA Atomic Energy Act
ARAR Applicable or relevant and appropriate requirement
BOD Biochemical oxygen demand
BTEX Benzene, toluene, ethylbenzene, and xylene
°C Degrees Celsius
CERCLA Comprehensive Environmental Response, Compensation, and Liability Act
CFR Code of Federal Regulations
CFU Colony-forming unit
Ciba Ciba-Geigy Corporation
CWA Clean Water Act
DOE U.S. Department of Energy
Edwards Edwards Air Force Base
EPA U.S. Environmental Protection Agency
FIFRA Federal Insecticide, Fungicide, and Rodenticide Act
°F Degrees Fahrenheit
GC Gas chromatography
gpd Gallons per day
gpm Gallons per minute
H2O2 Hydrogen peroxide
hv Ultraviolet radiation
kW Kilowatt
kWh Kilowatt-hour
°K Degrees Kelvin
Magnum Magnum Water Technology
Mannesmann Mannesmann Anlagenbau
MCL Maximum contaminant level
MEK Methyl ethyl ketone
MIBK Methyl isobutyl ketone
jtg/L Micrograms per liter
mg/L Milligrams per liter
nm Nanometers
NPDES National Pollutant Discharge Elimination System
NTU Nephelometric turbidity unit
OH« Hydroxyl radical
O&M Operation and maintenance
ORD Office of Research and Development
OSHA Occupational Safety and Health Act
OSWER Office of Solid Waste and Emergency Response
PCB Polychlorinated biphenyl
PCP Pentachlorophenol
POC Purgeable organic carbon
POTW Publicly owned treatment works
XI
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PPE Personal protective equipment
psi Pounds per square inch
QA Quality assurance
QC Quality control
RCRA Resource Conservation and Recovery Act
RFP Request For Proposal
RREL Risk Reduction Engineering Laboratory
SARA Superfund Amendments and Reauthorization Act
SDWA Safe Drinking Water Act
SITE Superfund Innovative Technology Evaluation
SVOC Semivolatile organic compound
TC Total carbon
TCE Trichloroethene
TCU Total color units
TER Technology Evaluation Report
TIC Tentatively identified compound
TOC Total organic carbon
TPH Total petroleum hydrocarbons
TRPH Total recoverable petroleum hydrocarbons
TSCA Toxic Substances Control Act
UCL Upper confidence limit
UV Ultraviolet
VOC Volatile organic compound
xil
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Conversion Factors
Measurement
Length
Area
Volume
Mass
Energy
Power
Temperature
To Convert From
inch
foot
mile
square foot
acre
gallon
cubic foot
pound
megajoule
horsepower
( "Fahrenheit - 32)
To
centimeter
meter
kilometer
square meter
square meter
liter
cubic meter
kilogram
kilowatt-hour
kilowatt
° Celsius
Multiply By
2.54
0.305
1.61
0.0929
4,047
3.78
0.0283
0.454
0.2776
0.7457
0.556
Xlll
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Acknowledgements
This report was prepared under the direction and coordination of Mr. Richard G. Eilers, U.S.
Environmental Protection Agency (EPA), Superfund Innovative Technology Evaluation (SITE) Program
Project Manager in the Risk Reduction Engineering Laboratory (RREL), Cincinnati, Ohio. Contributors
and reviewers for this report were Mr. Richard G. Eilers, Mr. Albert Venosa, Ms. Norma Lewis, and Mr.
Gordon Evans of EPA RREL, Cincinnati, Ohio; and Mr. Dale Cox and Mr. Jack Simser of Magnum
Water Technology.
The cooperation and participation of the Edwards Air Force Base personnel throughout the
demonstration is gratefully acknowledged.
This report was prepared for EPA's SITE Program by PRC Environmental Management, Inc., under
Contract No. 68-CO-0047.
xiv
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Section 1
Executive Summary
The patented CAV-OX* cavitation oxidation process,
developed by Magnum Water Technology (Magnum), was
demonstrated under the U. S. Environmental Protection Agency
(EPA) Superfund Innovative Technology Evaluation (SITE)
Program. The CAV-OX* process demonstration was conducted
over a 4-week period in March 1993, at Edwards Air Force
Base (Edwards) Site 16, California.
The CAV-OX* process is designed to destroy dissolved
organic contaminants in water. The process uses hydrodynamic
cavitation, ultraviolet (UV) radiation, and hydrogen peroxide
to oxidize organic compounds in water. This treatment process
produces no air emissions and generates no sludge or spent
media that require further processing, handling, or disposal.
Ideally, end products are water, carbon dioxide, halides (for
example, chloride), and in some cases, organic acids. In the
process a cavitation chamber induces hydrodynamic cavitation,
which occurs when a liquid undergoes a dynamic pressure
reduction while under constant temperature. The pressure
reduction causes gas bubbles to explosively develop, grow, and
then collapse. Cavitation decomposes water into extremely
reactive hydrogen atoms and hydroxyl radicals, which recombine
to form hydrogen peroxide and molecular hydrogen (Suslick
1989). The process also includes hydrogen peroxide and UV
radiation generated by mercury vapor lamps. The principal
oxidants in the process, hydroxyl and hydroperoxyl radicals,
are produced by both hydrodynamic cavitation and direct
photolysis of hydrogen peroxide at UV wavelengths.
The skid-mounted CAV-OX® process consists of the
cavitation chamber, UV reactor, and control panel unit.
Contaminated water is pumped through the cavitation chamber
where hydroxyl and hydroperoxyl radicals are produced. The
water then either enters the UV reactor or is recycled through
the cavitation chamber; the rate of recycle determines the
hydraulic retention time. Magnum recycles water through the
cavitation chamber to continue generation of hydroxyl and
hydroperoxyl radicals. Hydrogen peroxide is usually injected
into the process, in-line, between the cavitation chamber and
the UV reactor. In the UV reactor, the water flows through the
space between the reactor wall and a UV-transmissive quartz
tube in which a UV lamp is mounted. The treated water exits
the UV reactor through an effluent line.
For the demonstration, groundwater from Edwards Site 16
monitoring wells was pumped into an equalization tank. From
this tank, the water was pumped to an influent holding tank.
Hydrogen peroxide was added to the water in the influent holding
tank. Water was then pumped through a flow indicator and
past an influent sample port, then through the cavitation chamber
and UV reactor.
Three configurations of the CAV-OX* process were
demonstrated: the CAV-OX* I low-energy process; the
CAV-OX* II high-energy process operating at 5 kilowatts (kW);
and the CAV-OX* II high-energy process operating at 10 kW.
The CAV-OX* I process contained six 60-watt UV lamps in
one reactor, and the CAV-OX* II process contained two UV
reactors with one UV lamp each operating at 2.5 or 5 kW.
The CAV-OX* I and the CAV-OX* II processes were operated
simultaneously. Flow for the CAV-OX* I process varied from
0.5 to 1.5 gallons per minute (gpm). Flow for the CAV-OX* II
process varied from 1 to 4 gpm.
Primary objectives for the demonstration were to:
Determine trichloroethene (TCE) and benzene, toluene,
ethylbenzene, and xylene (BTEX) removal efficiencies
under different operating conditions
Determine whether TCE and BTEX levels in treated
groundwater meet applicable discharge limits to the
sanitary sewer at the 95 percent confidence level
Compare TCE and BTEX removal efficiencies among
the three process configurations
Secondary objectives for the demonstration were to:
• Collect information, including process chemical dosage
and utility requirements, needed to estimate treatment
costs
Assess the presence of degradation by-products in the
treated water
• Collect groundwater characterization data for both
influent and effluent streams
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This report presents information from the SITE
demonstration and several case studies that will be useful for
implementing the CAV-OX* process at hazardous waste sites
regulated by the Comprehensive Environmental Response,
Compensation, and Liability Act (CERCLA) and the Resource
Conservation and Recovery Act (RCRA). Section 2 presents
an overview of the SITE Program, discusses the purpose of
this report, describes the CAV-OX* process, and lists key
contacts. Section 3 discusses information relevant to the
process's application, including pretreatment and posttreatment
requirements, site characteristics, operating and maintenance
requirements, potential community exposures, and potentially
applicable environmental regulations. Section 4 summarizes
the costs associated with implementing the technology.
Appendixes A through C include the vendor claims for the
process, a summary of the demonstration results, and summaries
of nine case studies, respectively.
Overview of the SITE Demonstration
Shallow groundwater at Edwards Site 16 was selected as
the waste stream for evaluating the CAV-OX* process. About
8,500 gallons of groundwater contaminated with volatile organic
compounds (VOC) was treated during the demonstration. The
principal groundwater contaminants were TCE and BTEX,
which were present at concentrations of up to 2,100 micrograms
per liter (|xg/L). Groundwater was pumped from three monitoring
wells into a 7,500-gallon equalization (bladder) tank to minimize
variability in influent characteristics. Treated groundwater was
stored in a 21,000-gallon steel tank to await disposal.
The CAV-OX® equipment was transported in and operated
from the bed of a 1-ton stake body truck. The process equipment
functioned as planned after completing electrical and plumbing
connections. Equipment did not malfunction or require
maintenance during the 2-week demonstration.
The demonstration consisted of 15 planned runs for each
CAV-OX* configuration. Each run varied the operating
parameters of the CAV-OX* process. Samples from all three
configurations for one run were collected before the next run
began. The runs were conducted to demonstrate each
configuration under different operating conditions and to
compare the operation of the configurations.
The principal operating parameters for the CAV-OX*
process, hydrogen peroxide dose, hydraulic retention time
(determined by flow rate), and UV output, were varied to allow
observation of treatment process performance under different
operating conditions. Three hydrogen peroxide dosages were
demonstrated over three flow rates. UV output varied with the
three configurations. The process was also operated under
additional conditions as determined by Magnum. Groundwater
pH was lowered during two runs while operating under these
conditions. Although Magnum does not consider influent pH to
be a principal operating parameter and reports that pH has only
a minimal effect on the CAV-OX* process, influent pH was
varied in two runs because of its impact on other UV treatment
systems.
During the demonstration, samples were collected from the
influent and effluent lines of the CAV-OX* I and CAV-OX* II
processes. Influent and effluent samples were analyzed for
TCE, BTEX, other VOCs, semivolatile organic compounds
(SVOC), total organic carbon (TOC), total carbon (TC),
purgeable organic carbon (POC), metals, pH, alkalinity,
hardness, temperature, total recoverable petroleum hydrocarbons
(TRPH), specific conductance, hydrogen peroxide, and turbidity.
These samples were also analyzed for acute toxicity to freshwater
organisms using Ceriodaphnia dubia (water flea) and Pimephales
promelas (fathead minnow) as the test organisms.
Results from the SITE Demonstration
The following preferred operating conditions (those
conditions that reduced effluent VOCs to below target levels)
were determined for the CAV-OX* I configuration: an influent
hydrogen peroxide concentration of 23.4 milligrams per liter
(mg/L) and a flow rate of 0.6 gpm. At these conditions, the
effluent TCE and benzene levels were generally below target
levels (5 ug/L and 1 ug/L, respectively). The average removal
efficiencies for TCE and benzene were about 99.9 percent.
The following preferred operating conditions were
determined for the 5-kW CAV-OX* II configuration: an influent
hydrogen peroxide concentration of 48.3 mg/L and a flow rate
of 1.4 gpm. At these conditions, the effluent TCE and benzene
levels were generally below target levels. Average removal
efficiencies for TCE and benzene were about 99.8 percent.
The following preferred operating conditions were
determined for the 10-kW CAV-OX* II configuration: an
influent hydrogen peroxide concentration of 48.3 mg/L and a
flow rate of 1.4 gpm. At these conditions, the effluent TCE
and benzene levels were generally below target levels. Average
removal efficiencies for TCE and benzene were about 99.7 and
99.8 percent, respectively.
While operating under the preferred conditions, all
CAV-OX* configuration effluents met State of California
drinking water action levels and federal drinking water maximum
contaminant levels (MCL) for BTEX at the 95 percent confidence
level. Effluent from the CAV-OX* I process met the State of
California drinking water action level and federal drinking water
MCL for TCE at the 95 percent confidence level.
Bioassay analyses showed that influent was generally toxic
to both the fathead minnow and the water flea, and that the
CAV-OX* process effluent from runs without hydrogen peroxide
was nontoxic to the fathead minnow but moderately toxic to the
water flea. Bioassay analyses also showed that the CAV-OX*
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process effluent from runs with hydrogen peroxide was toxic to
both the fathead minnow and the water flea. Comparison of
effluent toxicity data with that of hydrogen peroxide
concentration in the effluent indicates that effluent toxicity may
be due partially to hydrogen peroxide rather than CAV-OX*
treatment by-products. Additional studies are needed to draw
definitive conclusions on effluent toxicity.
One change in groundwater characteristics was temperature.
In the CAV-OX® I configuration, the water temperature increased
at an average rate of about 0.26 °F per minute of UV exposure.
In the 5-kW CAV-OX* II process, the water temperature
increased at an average rate of about 2.36 °F per minute of UV
exposure. In the 10-kW CAV-OX* II process, the water
temperature increased at an average rate of 4.29 °F per minute
of UV exposure. Since the equipment was exposed to the
surrounding environment, the temperature increase may vary
with the ambient temperature or other atmospheric conditions.
Vendor-Provided Results From Case Studies
Nine case studies provided by Magnum are included in
Appendix C as additional performance data for the CAV-OX*
process. These cases involve both pilot- and full-scale units
treating contaminated groundwater and industrial wastewaters.
The contaminants of concern include pentachlorophenol (PCP),
total petroleum hydrocarbons (TPH), BTEX, biochemical
oxygen demand (BOD), TOC, atrazine, cyanide, and the
bacterium Salmonella.
Waste Applicability
Potential sites for applying the CAV-OX* process include
Superfund and other hazardous waste sites where groundwater
or aqueous wastes are contaminated with organic compounds
at mg/L levels or less. The process has been used to treat
groundwater and industrial wastewater containing a variety of
organic contaminants including phenols, herbicides, polynuclear
aromatic hydrocarbons, and petroleum hydrocarbons. During
the demonstration, influent concentrations of TCE and benzene
ranged from 1,500 to 2,000 and 250 to 500 ug/L, respectively.
Magnum reports that the CAV-OX* process has also treated
cyanide-contaminated wastewater and drinking water infected
with the bacterium Salmonella.
Economics
Using information from the SITE demonstration, 12 separate
cost categories for CAV-OX® treatment of contaminated
groundwater at a Superfund site were analyzed. This analysis
examined costs for the CAV-OX* I low-energy configuration
and the CAV-OX* II high-energy configuration using flow
rates of 10 and 25 gpm. Costs (in October 1993 dollars) for
each configuration are summarized below.
For the CAV-OX* I low-energy process, capital costs are
estimated to be about $314,500 for the 10-gpm process, of which
the CAV-OX* I process direct capital cost is $48,000. For the
25-gpm process, capital costs are estimated at about $342,500,
of which the CAV-OX® I process direct capital cost is $64,000.
Annual operation and maintenance (O&M) costs are estimated
to be about $71,000 for the 10-gpm process and $78,000 for
the 25-gpm process. Groundwater remediation costs are
estimated to be about $30 per 1,000 gallons for the 10-gpm
process, of which CAV-OX* I process direct costs are $10. For
the 25-gpm process, groundwater remediation costs are estimated
to be about $13 per 1,000 gallons, of which CAV-OX* I process
direct costs are $5.
For the CAV-OX* II high-energy process, capital costs are
estimated to be about $314,500 for the 10-gpm process, of which
the CAV-OX* II process direct capital cost is $48,000. For the
25-gpm process, capital costs are estimated at about $342,500,
of which the CAV-OX* II process direct capital cost is $64,000.
Annual O&M costs are estimated to be about $75,000 for the
10-gpm process and $86,000 for the 25-gpm process.
Groundwater remediation costs are estimated to be about $31
per 1,000 gallons for the 10-gpm process, of which CAV-OX*
II process direct costs are $11. For the 25-gpm process,
groundwater remediation costs are estimated to be about $14
per 1,000 gallons, of which CAV-OX* II process direct costs
are $5. Table 1 summarizes CAV-OX* process costs.
For the case studies provided by Magnum, costs ranged from
$1.62 to $1.93 per 1,000 gallons of water containing organic
contaminants. For one case study, the cost to reduce BOD using
only the cavitation chamber was $0.13 per 1,000 gallons.
Table 1. CAV-OX* Process Cost Summary
CAV-OX* I
Low-Energy
Process Costs ($)
CAV-OX* II
High-Energy
Process Costs ($)
10 gpm 25 gpm 10 gpm 25 gpm
Capital
CAV-OX® Process
Direct Capital
Annual O&M
Groundwater
Remediation per
1,000 gallons
CAV-OX® Process
Direct per 1,000
gallons
314,500
48,000
71,000
30
10
342,500
64,000
78,000
13
5
314,500
48,000
75,000
31
11
342,500
64,000
86,000
14
5
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Section 2
Introduction
This section describes the SITE Program, the purpose of
this report, and the CAV-OX* cavitation oxidation process
developed by Magnum. The CAV-OX* process is designed to
treat waters contaminated with low concentrations of organic
compounds. For additional information about the SITE
Program, the CAV-OX* process, or the demonstration site, key
contacts are listed at the end of this section.
Purpose, History, and Goals of the SITE Program
The Superfund Amendments and Reauthorization Act
(SARA) of 1986 mandates that EPA select, to the maximum
extent practicable, remedial actions at Superfund sites that create
permanent solutions (as opposed to land-based disposal) for
contamination that affects human health and the environment.
In doing so, EPA is directed to use alternative or resource
recovery technologies. In response, EPA's Office of Research
and Development (ORD) and Office of Solid Waste and
Emergency Response (OSWER) established four programs: (1)
one program to accelerate the use of new or innovative
technologies to clean up Superfund sites through field
demonstrations, (2) one to foster the further research and
development of treatment technologies that are at the laboratory
or pilot scale, (3) one to demonstrate and evaluate new or
innovative measurement and monitoring technologies, and (4)
one to disseminate technical information to the user community.
Together, these four programs make up the SITE Program.
The primary purpose of the SITE Program is to enhance
the development and demonstration, and thereby establish the
commercial availability, of innovative technologies applicable
to Superfund sites. The SITE Program has established the
following goals:
• Identify and remove impediments to the development
and commercial use of alternative technologies
• Demonstrate promising innovative technologies to
establish reliable performance and cost information that
can be used for site characterization and remediation
decisions
Develop procedures and policies that encourage the
selection of alternative treatment remedies at Superfund
sites
• Develop a program that promotes and supports
emerging technologies
EPA recognizes that several factors inhibit the expanded
use of new and alternative technologies at Superfund sites. The
SITE Program's goals are designed to identify the most
promising new technologies, develop pertinent and useful data
of known quality about these technologies, and make the data
available to Superfund decision-makers. An additional goal is
to promote the development of emerging innovative technologies
from the laboratory-, pilot-, or bench-scale stage to the full-
scale stage.
Implementation of the SITE Program is a significant ongoing
effort involving ORD, OSWER, various EPA Regions, and
private businesses, including technology developers and parties
responsible for site remediation. The technology selection
process and the field demonstration together provide objective
and carefully controlled testing of field-ready technologies.
Through government publications, the SITE Program
disseminates testing results to Superfund decision-makers for
use in evaluating the applicability of technologies to sites
requiring remediation.
The demonstration process collects the following information
for Superfund decision-makers to consider when matching
technologies with wastes, media, and sites requiring remediation:
The technology's effectiveness based on field
demonstration sampling and analytical data collected
during the demonstration
• The potential need for pretreatment and posttreatment
of wastes
• Site-specific wastes and media to which the
technology can be applied
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Potential site-specific process operating problems as
well as possible solutions
• Approximate capital, operating, and maintenance costs
• Projected long-term operating and maintenance costs
Innovative technologies chosen for a demonstration must
be pilot- or full-scale applications and must offer some advantage
over existing technologies. Mobile technologies are of particular
interest. Cooperative agreements between EPA and the
developer determine responsibilities for demonstrating and
evaluating the technology. The developer is responsible for
operating the technology at the selected site and is expected to
pay the costs to transport, operate, and remove the equipment.
EPA is responsible for project planning, sampling and analyses,
quality assurance (QA), quality control (QC), report preparation,
and technology transfer. Each year the SITE Program sponsors
demonstrations of approximately 10 technologies.
Documentation of the SITE Demonstration Results
The results of each SITE demonstration are reported in two
documents: the Applications Analysis Report (AAR) and the
Technology Evaluation Report (TER). The AAR is intended
for decision-makers responsible for implementing specific
remedial actions and is primarily used to assist in screening the
demonstrated technology as an option for a particular cleanup
situation. The purpose of the AAR is discussed in more detail
in the following section.
The TER is published separately from the AAR and provides
a comprehensive description of the demonstration and its results.
A likely audience for the TER includes engineers responsible
for evaluating the technology performance for specific sites
and wastes. These technical evaluators seek to thoroughly
understand the performance of the technology during the
demonstration as well as advantages, disadvantages, and costs
of the technology for a specific application. The report also
provides a detailed QA/QC discussion. This information is
used to produce conceptual designs in sufficient detail to develop
preliminary cost estimates for the demonstrated technology. If
the candidate technology appears to meet the needs of site
engineers, it will be analyzed more thoroughly using the TER,
the AAR, and other site-specific information obtained from
remedial investigations.
Purpose of the Applications Analysis Report
Information presented in the AAR is intended to assist
Superfund decision-makers in screening specific technologies
for a particular cleanup situation. The report discusses
advantages, disadvantages, and limitations of the technology.
Costs of the technology for different applications are estimated
on the basis of available data for pilot- and full-scale applications.
The report discusses factors that have a major impact on cost
and performance, such as site and waste characteristics. In
addition, EPA evaluates the applicability of each technology for
specific sites and wastes, other than those already tested, and
studies the estimated costs of the applications. These results are
also presented in the AAR.
Each demonstration evaluates a technology's performance
in treating an individual waste type at a particular site. To
obtain data with broad applicability, priority is given to
technologies that treat wastes frequently found at Superfund
sites. In many cases, however, wastes at other sites will differ
in some way from the waste treated at the demonstration site.
Therefore, the successful demonstration of a technology at one
site does not ensure its success at others. Data obtained from
the demonstration may require extrapolation to estimate total
operating ranges over which the technology performs
satisfactorily. Any extrapolation of demonstration data should
also be based on other available information about the
technology.
The amount of available data for the evaluation of an
innovative technology varies widely. Data may be limited to
laboratory tests on synthetic wastes or may include performance
data on actual wastes treated by pilot- or full-scale treatment
systems. In addition, only limited conclusions regarding
Superfund applications can be drawn from a single field
demonstration. A successful field demonstration does not
necessarily ensure that a technology will be widely applicable
or that it will be fully developed to commercial scale.
This AAR synthesizes available information on Magnum's
C AV-OX* process and draws reasonable conclusions regarding
its range of applicability. This AAR will be useful to decision-
makers considering using the CAV-OX* process. It represents
a critical step in the development and commercialization of this
treatment technology.
Technology Description
In February 1992, Magnum responded to EPA's request
for proposal (RFP) for participation in the SITE Program.
Magnum proposed demonstrating the CAV-OX* process to treat
contaminated groundwater at Edwards under the SITE Program.
EPA subsequently accepted the C AV-OX* process into the SITE
Program. Through a cooperative effort among EPA ORD,
EPA Region 9, the State of California, Edwards, and Magnum,
the CAV-OX* process was demonstrated at Edwards Site 16.
Treatment Technology
The CAV-OX* process was developed by Magnum to
destroy dissolved organic contaminants in water. Two United
States patents and two U.S. patents pending protect the
CAV-OX* process.
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The process uses hydrodynamic cavitation, UV radiation,
and hydrogen peroxide to oxidize organic compounds present
in water at mg/L levels or less. Oxidation is a chemical change
in which electrons are lost by an atom or a group of atoms.
Oxidation of an atom or group of atoms is always accompanied
by the reduction of another atom or group of atoms. Reduction
is a chemical change in which electrons are gained by an atom
or group of atoms. The atom or group of atoms that has lost
electrons has been oxidized, and the atom or group of atoms
that has gained electrons has been reduced. The reduced atom
or group of atoms is called an oxidant. Oxidation and reduction
always occur simultaneously, and the number of electrons lost
in oxidation must equal the number of electrons gained in
reduction. In the CAV-OX* process, organic contaminants in
water are oxidized by hydroxyl and hydroperoxyl radicals,
produced by hydrodynamic cavitation, UV radiation, and
hydrogen peroxide. Subsequently, the organic contaminants
are broken down into carbon dioxide, water, halides, and in
some cases, organic acids.
A variety of organic contaminants can be effectively oxidized
by the combined use of (1) UV radiation and hydrogen peroxide,
(2) UV radiation and ozone, or (3) ozone and hydrogen peroxide.
The principal oxidants in the CAV-OX* process, hydroxyl and
hydroperoxyl radicals, are produced by either hydrodynamic
cavitation or direct UV photolysis of hydrogen peroxide that
has been added to contaminated water.
In principle, the most direct way to generate hydroxyl
radicals is to cleave hydrogen peroxide through photolysis.
Photolysis of hydrogen peroxide occurs when UV radiation is
applied, as shown in the following reaction:
where:
H2O2 + hv -> 2 OH-
H2O2= hydrogen peroxide
hv = UV radiation
OH = hydroxyl radicals
Thus, photolysis of hydrogen peroxide results in a quantum
yield of two hydroxyl radicals formed per quantum of radiation
absorbed. This ratio of hydroxyl radicals generated from the
photolysis of hydrogen peroxide is high. Unfortunately, at 253.7
nanometers (nm), the dominant emission wavelength of low-
pressure UV lamps (CAV-OX* I), the absorptivity (or molar
extinction coefficient) of hydrogen peroxide is only 19.6 liters
per mole-centimeter. This absorptivity is relatively low for a
primary absorber in a photochemical process. Because of the
low absorptivity value for hydrogen peroxide, a high
concentration of residual hydrogen peroxide must be present in
the treatment medium to generate a sufficient concentration of
hydroxyl radicals.
The hydroxyl radicals formed by photolysis react rapidly
with organic compounds, with rate constants on the order of
108 to 1010 liters per mole-second; they also have a relatively
low selectivity in their reactions (Glaze and others 1987).
However, naturally occurring water components, such as
carbonate ion, bicarbonate ion, and some oxidizable species,
act as free radical scavengers that consume hydroxyl radicals.
Free radical scavengers are compounds that consume any species
possessing at least one unpaired electron. In addition to naturally
occurring scavengers, excess hydrogen peroxide can itself act
as a free radical scavenger, decreasing the hydroxyl radical
concentration and thus slowing reaction rates.
Magnum adds the component of hydraulic cavitation; that
is, the expansion and activity of bubbles generated by static or
dynamic pressure reductions in a liquid. Boiling, a similar and
more familiar event, is the expansion and activity of bubbles
generated by temperature increases in a liquid. Cavitation can
be induced by several means. For example, sound waves can
cause pressure reductions resulting in acoustic cavitation. Also,
the flow path of a liquid can be manipulated to reduce pressure,
resulting in hydrodynamic cavitation. The CAV-OX* cavitation
chamber is designed to generate hydrodynamic cavitation by
manipulating the flow path of water. The bubbles produced in
cavitation may contain gas, vapor, or a mixture of gas and
vapor. Bubbles explosively develop, grow, and then collapse
at a microscopic level. Research of acoustical cavitation reports
the temperature of the bubble collapse to be about 5,000 degrees
Kelvin (Flint and Suslick 1991). Additional research has shown
that acoustical cavitation decomposes water into extremely
reactive hydrogen atoms and hydroxyl radicals, which recombine
to form hydrogen peroxide and molecular hydrogen (Suslick
1989). Numerous reduction or oxidation reactions may occur
under these conditions. The rate at which cavitation decomposes
water into hydrogen atoms and hydroxyl radicals is not known.
Reaction with hydroxyl radicals is not the only removal
pathway possible in the CAV-OX* process; hydraulic cavitation
destruction and direct photolysis by UV radiation of organic
compounds also provide a removal pathway for contaminants.
With these factors affecting the reaction, the proportion of
oxidants required for optimum removal is difficult to
predetermine. Instead, the proportion for optimum removal
must be determined experimentally for each waste type.
The principal operating parameters for the CAV-OX* process
are hydrogen peroxide dose, hydraulic retention time (determined
by flow rate), and UV output. Typically, during treatability
studies, initial values of these parameters are selected based on
Magnum's experience and the anticipated effects of the operating
parameters on treatment process performance. These operating
parameters are discussed briefly below. Their effects on
performance are discussed in detail in Section 3.
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Process Components and Function
Innovative Features of the Technology
Each CAV-OX® process consists of a portable, truck- or
skid-mounted module, with the following components: cavitation
chamber, cavitation pump, UV reactor, and control panel unit.
The control panel unit includes electrical switches, indicator
lamps, circuit breakers, and UV ballasts. In addition to these
main process components, other equipment is used to address
site-specific conditions or requirements, including contaminated
water characteristics and effluent discharge limits. Figure 1
illustrates the main and ancillary components of the CAV-OX®
technology demonstrated at Edwards Site 16.
For the SITE demonstration, groundwaterwas pumped from
three monitoring wells into a 7,500-gallon equalization (bladder)
tank to minimize variability in influent characteristics.
Groundwaterwas primarily contaminated with VOCs, including
TCE and BTEX. Treated groundwater was stored in a 21,000-
gallon steel tank to await disposal.
Both the CAV-OX® I low-energy process and the CAV-OX®
II high-energy process were demonstrated at Edwards. Three
configurations of the CAV-OX® process were demonstrated. One
configuration was the CAV-OX® I process, which contained one
reactor with six 60-watt low-pressure UV lamps and operated at
360 watts. The second and third configurations were the
CAV-OX* II process which operated at 5 and 10 kW,
respectively. The CAV-OX® II process contained two UV
reactors with one high-pressure UV lamp operating at 2.5 or 5
kW each. The CAV-OX® process generates UV radiation by
mercury-vapor lamps. Each UV lamp is housed in a UV-
transmissive quartz tube, mounted entirely within the UV reactor.
The low-energy reactor has a volume of about 10 gallons and
each high-energy reactor has a volume of about 6 gallons. Water
flows through the space between the reactor wall and the quartz
tube.
Contaminated water is pumped to the treatment process
and enters the cavitation chamber through a section of pipe also
containing a flow meter and an influent sampling port. Inside
the cavitation chamber, the contaminated water undergoes
extreme pressure variations resulting in hydrodynamic cavitation.
Hydrogen peroxide is usually added to the contaminated water
in-line between the cavitation chamber and the UV reactor.
However, for the demonstration, hydrogen peroxide was added
to the influent holding tank. Inside the UV reactor, photolysis
" hydrogen peroxide b;r UV radiation results in additional
formation of hydroxyl radicals; these free radicals then react
rapidly with the organic contaminants. Treated water exits the
UV reactor through an effluent pipe equipped with a flow gauge
and effluent sample port.
Common methods for treating groundwater contaminated
with solvents and other organic compounds include air stripping,
steam stripping, carbon adsorption, chemical oxidation, and
biological treatment. As compliance with regulatory
requirements for secondary wastes and treatment by-products
has become more stringent and expensive, oxidation technologies
have been known to offer a major advantage over other treatment
techniques: chemical oxidation technologies destroy
contaminants rather than transferring them to another medium,
such as activated carbon or the ambient air. Also, chemical
oxidation technologies offer faster reaction rates than other
technologies, such as some biological treatment systems.
However, the oxidation of organics by ozone, hydrogen
peroxide, or UV radiation alone has kinetic limitations, thus
restricting its applicability to a range of contaminants. Because
of these limitations, conventional chemical oxidation
technologies have been slow to become cost-competitive
treatment options.
A combination of oxidative forces generally increases
destruction efficiency, allowing more contaminants to be treated.
In the CAV-OX* process Magnum combines hydrodynamic
cavitation, UV radiation, and hydrogen peroxide. Hydroxyl
and hydroperoxyl radicals formed by hydrodynamic cavitation
and UV photolysis of hydrogen peroxide rapidly oxidize the
contaminants and exhibit little contaminant selectivity.
The CAV-OX® process produces no air emissions and
generates no sludge or spent media that require further
processing, handling, or disposal. Ideally, end products include
water, carbon dioxide, halides, and in some cases, organic acids.
However, other oxidizable species present in the water (including
metals in reduced form, cyanides, and nitrites) may also be
oxidized in the process and can exert an additional oxidant
demand. In other UV systems, after oxidation, metals tend to
precipitate as suspended solids resulting in UV lamp scaling.
However, Magnum reports that scaling does not occur in the
CAV-OX® process.
Hydrogen peroxide is inexpensive, easy to handle, and
readily available. As a result, its use with hydrodynamic
cavitation and UV radiation in the CAV-OX* process offers
considerable advantages over expensive and difficult-to-handle
chemicals.
Table 2 compares several treatment options for water
contaminated with VOCs. Similar comparisons can be made
for SVOCs, polychlorinated biphenyls (PCB), and pesticides,
although air stripping is not generally applicable to these types
of contaminants.
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Figure 1. The CA V-OX" Process as Demonstrated
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Table 2. Comparison of Technologies for Treating VOCs in Water
Technology
Advantages
Disadvantages
Air stripping
Effective at all concentrations;
mechanically simple; relatively inexpensive
Innefficient at low concentrations; VOCs
discharged to air
Steam stripping
Effective at all concentrations; removes a
wide variety of VOCs
VOCs discharged to air; high energy
consumption
Air stripping with carbon adsorption of
vapors
Air stripping with carbon adsorption of
vapors combined with spent carbon
regeneration
Carbon adsorption (liquid phase)
Biological treatment
Other enhanced oxidation processes
CAV-OX® process
Effective at all concentrations
Effective at all concentrations; no carbon
disposal costs; can reclaim the product
Effective at all concentrations; low air
emissions; relatively inexpensive
Low air emissions; relatively inexpensive;
low energy requirements; VOCs destroyed
Effective at low concentrations; no air
emissions; no secondary waste; VOCs
destroyed
Effective at low concentrations; no air
emissions; no secondary waste; VOCs
destroyed
Inefficient at low concentrations;
generates large volumes of spent
carbon requiring disposal or
regeneration
Inefficient at low and high
concentrations; high energy
consumption
Inefficient at low concentrations;
requires disposal or regeneration of
spent carbon
Inefficient at high concentrations;
generally not effective for chlorinated
aliphatic compounds; slow rates of
removal; sludge treatment and disposal
required
High energy consumption; not cost
effective at high concentrations
High energy consumption; not cost
effective at high concentrations; process
mechanisms not well documented
Key Contacts
Additional information on the CAV-OX* process, the SITE
Program, and Edwards Site 16 can be obtained from the
following sources:
The CAV-OX* Process
Dale Cox
President
Magnum Water Technology
600 Lairport Street
El Segundo, CA 90245
(310)640-7000
Edwards Air Force Base
John Haire
Environmental Coordinator
AFFTC/Public Affairs
2 S. Rosamond Boulevard
Edwards Air Force Base, CA 93524-1225
(805)277-3510
The SITE Program
Richard G. Eilers
EPA Project Manager
EPA SITE Program
26 West Martin Luther King Drive
Cincinnati, OH 45268
(513)569-7809
10
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Section 3
Technology Applications Analysis
This section addresses the applicability of the CAV-OX*
process for treatment of water contaminated with organic
compounds. Magnum's claims regarding the applicability and
performance of the CAV-OX* technology are included in
Appendix A. Because results from the SITE demonstration
provided an extensive database, evaluation of the technology's
effectiveness and its potential applicability to contaminated sites
is mainly based on these results, which are presented in
Appendix B. The SITE demonstration results are supplemented
by results from nine case studies, which are presented in
Appendix C.
This section summarizes the effectiveness of the CAV-OX*
process and discusses the following topics in relation to its
applicability: effectiveness of the process, factors influencing
performance, site characteristics, material handling
requirements, personnel requirements, potential community
exposures, and potential regulatory requirements.
Effectiveness of the CAV-OX® Process
This section discusses the effectiveness of the CAV-OX*
process based on results from the SITE demonstration and nine
other case studies.
Results of the SITE Demonstration
The SITE demonstration was conducted at Edwards Site 16
in California over a 4-week period in March 1993. During the
demonstration, both the CAV-OX* I low-energy process and
the CAV-OX® II process treated about 8,500 gallons of
groundwater contaminated with VOCs, mainly TCE andBTEX.
Other VOCs (methylene chloride, acetone, and 1,2-
dichloroethene) were present at low levels. Groundwater was
pumped from three monitoring wells into a 7,500-gallon
equalization (bladder) tank to minimize variability in influent
characteristics. Treated groundwater was stored in a 21,000-
gallon steel tank to await disposal. During the demonstration,
flow for the CAV-OX* I process varied from 0.5 to 1.5 gpm.
Flow for the CAV-OX* II process varied from 1 to 4 gpm.
These pilot-scale flow rates are directly applicable to a full-
scale process.
The CAV-OX* process demonstration had both primary and
secondary objectives. Primary objectives were considered critical
for the technology evaluation. Secondary objectives provided
additional information that was useful but not critical. The
primary demonstration objectives were to:
Determine TCE and BTEX removal efficiencies in the
treatment process under different operating conditions
Determine whether TCE and BTEX levels in treated
groundwater meet applicable discharge limits to the
sanitary sewer at the 95 percent confidence level
• Compare TCE and BTEX removal efficiencies among
the three process configurations
Secondary objectives for the demonstration were to:
• Collect information, including process chemicaldosage
and utility requirements, needed to estimate treatment
costs
Assess the presence of degradation by-products in the
treated water
Collect groundwater characterization data for both
influent and effluent streams
The demonstration consisted of 15 planned runs for each
configuration. The first run was conducted using the operating
conditions recommended by Magnum. For subsequent runs,
operating parameters were varied, as discussed in Appendix B,
to allow observation of each treatment process performance
under different operating conditions.
During the demonstration, samples were collected from the
main feed line from the influent holding tank and the effluent
lines from the CAV-OX® I and CAV-OX* II UV reactors.
Influent and effluent samples were analyzed for TCE, BTEX,
other VOCs, SVOCs, TOC, TC, POC, metals, pH, alkalinity,
hardness, temperature, TRPH, specific conductance, hydrogen
peroxide, and turbidity. These samples were also analyzed for
acute toxicity to freshwater organisms.
11
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Appendix B summarizes (1) the site description, (2) the site
contamination characteristics, (3) the SITE demonstration, (4)
the experimental design, and (4) the treatment results. Key
findings of the demonstration are as follows:
The following preferred operating conditions were
determined for the CAV-OX® I configuration: an influent
hydrogen peroxide level of 23.4 mg/L and a flow rate of
0.6 gpm. At these conditions, the effluentTCE and benzene
levels were generally below target levels (5 ug/L and 1 ug/L,
respectively). The average removal efficiencies for TCE and
benzene were about 99.9 percent.
• The following preferred operating conditions were
determined for the CAV-OX* II configuration: an
influent hydrogen peroxide level of 48.3 mg/L and a
flow rate of 1.4 gpm. At these conditions, the effluent
TCE and benzene levels were generally below target
levels. The average removal efficiencies for TCE and
benzene were about 99.7 and 99.8 percent,
respectively.
While operating under the preferred conditions,
effluents from all CAV-OX® configurations met State
of California drinking water action levels and federal
drinking water MCLs for BTEX at the 95 percent
confidence level. Effluent from the CAV-OX* I process
met State of California drinking water action levels and
federal drinking water MCLs for TCE at the 95 percent
confidence level.
• Bioassay analyses showed that untreated influent was
generally toxic to both the fathead minnow and the
water flea and that the CAV-OX* process effluent from
runs without hydrogen peroxide was nontoxic to the
fathead minnow but moderately toxic to the water flea.
Bioassay analyses also showed that the CAV-OX*
process effluent from runs with hydrogen peroxide was
toxic to both the fathead minnow and the water flea.
Comparison of effluent toxicity data with that of
hydrogen peroxide concentration in the effluent
indicates that effluent toxicity may be due partially to
hydrogen peroxide rather than CAV-OX® treatment
by-products. Additional studies are needed to draw
definitive conclusions on the effluent toxicity.
• One change ip groundwater characteristics was
temperature. In the CAV-OX* I configuration, the
water temperature increased at an average rate of about
0.26 °F per minute of UV exposure. In the 5-kW
CAV-OX*II process, the water temperature increased
at an average rate of about 2.36 °F per minute of UV
exposure. In the 10-kW CAV-OX* II process, the water
temperature increased at an average rate of 4.29 °F per
minute of UV exposure. Since the equipment was
exposed to the surrounding environment, the
temperature increase may vary with the ambient
temperature or other atmospheric conditions.
No scaling was observed on any of the tubes. Magnum
icports that scaling does not occur in the CAV-OX*
process. Scaling increases maintenance costs and
decreases efficiency.
• Electricity is the only utility requirement for the
CAV-OX* process. Electricity demand was 2.2 kW
for the CAV-OX® I process, 6.4 kW for the 5-kW
CAV-OX«II process, and 13 kW for the 10-kW
CAV-OX* II process.
Results of Other Case Studies
Results of nine case studies provided by Magnum
(Appendix C) are included as additional performance data for
the CAV-OX* process. These claims and interpretations are
those made by Magnum and have not necessarily been
substantiated by test data. These cases involve both pilot- and
full-scale units treating contaminated groundwater and industrial
wastewaters. Contaminants of concern included PCP, TPH,
BTEX, BOD, TOC, atrazine, cyanide, phenol, and the
bacterium Salmonella.
Factors Influencing Performance
Several factors influence the effectiveness of the CAV-OX®
process. These factors can be grouped into three categories:
(1) influent characteristics, (2) operating parameters, and (3)
maintenance requirements. Each of these is discussed below.
Influent Characteristics
The CAV-OX® process uses chemical oxidation to destroy
organic contaminants; therefore, other species in the influent
that consume oxidants present an additional load for the process.
These species are called scavengers. A scavenger may be
described as any species in water, other than the target
contaminants, that consumes oxidants. Common scavengers
include anions such as bicarbonates, carbonates, sulfides,
nitrites, bromides, and cyanides. Metals present in reduced
states, such as trivalent chromium, ferrous ion (Fe+2),
manganous ion (Mn+2), and several others, are also likely to be
oxidized. In addition to acting as scavengers, these reduced
metals can cause concerns under alkaline conditions. For
example, trivalent chromium can be oxidized to hexavalent
chromium, which is more toxic. Ferrous ion and manganous
ion are converted to less soluble forms, which precipitate in the
reactor, creating suspended solids that can build up on the quartz
tubes housing the UV lamps. Natural organic compounds, such
as humic acid (often measured as TOC), are also potential
scavengers that can affect treatment efficiency.
12
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The concentrations of carbonate and bicarbonate influence
the performance of the CAV-OX® process. These ions exert an
oxidant demand on the process by absorbing UV light and
scavenging hydroxyl radicals. However, influent pH can be
adjusted to minimize these effects.
Metals present in a reduced state (such as iron or manganese)
are oxidized by the UV process. Conversion of metals to forms
that are less soluble at higher oxidation states (for example,
Fe+2 to Fe+3) may result in coating of the quartz tubes housing
the UV lamps; this would cause poor UV transmission and
therefore interfere with contaminant destruction. However,
Magnum reports that scaling of this nature has never occurred
with the CAV-OX® process.
The CAV-OX* process can treat water containing a variety
of VOCs, such as TCE and BTEX. Under a given set of
operating conditions, contaminant removal efficiencies depend
on the chemical structure of the contaminants. Removal
efficiencies are high for organic contaminants with double bonds
(such as TCE and vinyl chloride) and aromatic compounds (such
as phenol, benzene, toluene, and xylene), because these
compounds are easy to oxidize. Organic contaminants without
double bonds (such as chloroform) are not easily oxidized and
are thus more difficult to remove.
Contaminant concentration is a major factor affecting
treatment process effectiveness. The CAV-OX® process is most
effective in treating water with contaminant concentrations
present in water at mg/L levels or less. If contaminant
concentrations are greater, the CAV-OX® process may be used
in combination with other treatment technologies such as air
stripping. For highly contaminated water, Magnum increases
the flow of water recycled through the cavitation chamber for
continued production of hydroxyl and hydroperoxyl radicals.
Operating Parameters
Operating parameters are those procedures that can be varied
during the treatment process to achieve desired removal
efficiencies. The principal operating parameters for the
CAV-OX® process are hydrogen peroxide dose, hydraulic
retention time, and UV output. During the demonstration, each
of these parameters was varied to observe each treatment process
performance under different operating conditions.
The hydrogen peroxide dose is based on treatment process
configuration, contaminated water chemistry, and contaminant
oxidation rates. Under ideal conditions, hydrogen peroxide is
photolyzed to hydroxyl and hydroperoxyl radicals, which oxidize
contaminants in the groundwater. Direct photolysis of each
molecule of hydrogen peroxide results in a yield of two hydroxyl
radicals. The molar extinction coefficient of hydrogen peroxide
at 253.7 nm, the dominant emission wavelength of low-pressure
UV lamps, is only 19.6 liters per mole-centimeter, which is
low for a primary absorber in a photochemical process (Glaze
and others 1987). Therefore, although the yield of hydroxyl
radicals from hydrogen peroxide photolysis is relatively high,
the low molar extinction coefficient requires a relatively high
concentration of hydrogen peroxide in the water. However,
because excess hydrogen peroxide is also a hydroxyl radical
scavenger, hydrogen peroxide levels that are too high could
result in a net decrease in treatment efficiency. Thus, an
optimum concentration of hydrogen peroxide must be maintained
at all times.
Flow rate through the treatment process determines UV
reactor retention time. Increasing or decreasing the flow rate
will affect the treatment efficiency by changing the time available
for hydroxyl radical formation and contaminant destruction.
During the demonstration, flow for the CAV-OX® I process
varied from 0.5 to 1.5 gpm. Flow for the CAV-OX® II process
varied from 1 to 4 gpm. These pilot-scale flow rates are directly
applicable to a full-scale process.
UV output varies with the type of CAV-OX® process being
operated. The CAV-OX® I low-energy process has a UV output
of 360 watts, while the CAV-OX® II high-energy process can
operate at 2.5, 5, 7.5, or 10 kW.
Influent pH is a critical operating parameter in other UV
systems. It controls the equilibrium among carbonate,
bicarbonate, and caibonic acid. This equilibrium is important
to treatment efficiency because carbonate and bicarbonate ions
are hydroxyl radical scavengers. If the influent carbonate and
bicarbonate concentration is greater than about 400 mg/L as
calcium carbonate, the pH should be lowered to between 4 and
6 to improve the treatment efficiency. At low pH, the carbonate
equilibrium is shifted to carbonic acid, which is not a scavenger.
However, Magnum does not consider influent pH a principal
operating parameter for the CAV-OX* process.
Maintenance Requirements
The maintenance requirements for the CAV-OX® process
are based on discussions with Magnum during and after the
SITE demonstration. Magnum bases its information on (1)
production units operating in the field, (2) the SITE
demonstration at Edwards, and (3) research and development
testing performed by Magnum over several years. Regular
maintenance by trained personnel is essential for the successful
operation of the CAV-OX® process. However, the only major
process component that requires regular maintenance is the UV
lamp assembly.
Regular UV lamp assembly maintenance includes periodic
cleaning of the quartz tubes housing the UV lamps. Eventually,
the lamps may need to be replaced. The frequency of quartz
tube cleaning depends on the type and concentration of suspended
solids present in the influent or formed during treatment. UV
lamp assemblies can be removed from the oxidation unit to
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provide access to the quartz tubes, which can then be cleaned
manually. Magnum recommends cleaning the quartz tubes by
wiping them monthly with a clean cloth, although at existing
CAV-OX* operations, this maintenance is performed once every
3 months.
The life of UV lamps used hi the CAV-OX* process normally
cited by most manufacturers is 7,500 hours, given a use cycle
of 8 hours, which represents the length of time the UV lamp is
operated between shutdowns. Decreasing the use cycle or
increasing the frequency at which a UV lamp is turned on and
off can lead to early lamp failure.
A number of factors contribute to UV lamp aging. These
factors include plating of mercury to the interior lamp walls, a
process called blackening, and solarization of the lamp enclosure
material, which reduces its transmissibility. These factors cause
steady deterioration in lamp output at the effective wavelength
and may reduce output at the end of a lamp's life by 40 to
60 percent. This reduction in lamp output requires more frequent
replacement of the UV lamps. According to Magnum, based
on lamp specifications, UV lamp output does not decline
significantly until after about 10,000 hours of operation for the
CAV-OX® I process and 3,000 hours of operation for the
CAV-OX* [I process. Therefore, Magnum recommends
replacing the UV lamps after about 7,500 hours and 2,000 hours,
respectively
During and after the demonstration, no scaling was observed
on any of the UV tubes. Magnum reports that scaling does not
occur in the CAV-OX* process. The equipment functioned as
planned after completing electrical and plumbing connections.
No equipment malfunctioned or required maintenance during
the 2-week demonstration.
The CAV-OX* process requires little attention during
operation and can be operated and monitored remotely, if
needed. Remotely monitored systems can be connected to
devices that automatically dial a telephone to notify responsible
parties at remote locations of divergent operating conditions in
the CAV-OX* equipment. Remotely operated and monitored
systems are hard-wired into central control panels or computers
through programmable logic controllers.
Other components of the CAV-OX* process, such as valves,
flow meters, tanks, piping, and the hydrogen peroxide feed
module should be visually checked for leaks once a week.
Monthly maintenance includes inspection of all electrical
components, pumps, and the UV reactor. Monthly maintenance
of the UV reactor includes removing aluminum seals and
removing, inspecting, and wiping the quartz tubes. Annual
maintenance (or more frequent if indicated by monthly
inspections) should include replacement of UV lamps and quartz
tubes. Magnum reports that corrosion of the cavitation chamber
due to cavitation does not occur.
Site Characteristics
In addition to influent characteristics and effluent discharge
requirements, site characteristics are important when considering
the CAV-OX* process. Site-specific factors can impact the
CAV-OX* process, and should be considered before selecting
the technology for remediation of a specific site. Site-specific
factors include support systems, site access, climate, utilities,
and services and supplies. Section 4 identifies examples of
categories that are specific to the CAV-OX* process and to a
hazardous waste remediation site.
Support Systems
To clean up contaminated groundwater, extraction wells
and a groundwater collection and distribution system must be
installed to pump groundwater to a central facility. Because
the CAV-OX* process is normally operated as a continuous flow-
through process, it may be necessary to install several extraction
wells in order to provide a continuous supply of groundwater.
An equalization tank may be required if flow rates from the
groundwater wells fluctuate or if contaminant concentrations
vary. When installing a groundwater collection and distribution
system, preventive measures should be considered to reduce
volatile contaminant losses.
Before choosing the CAV-OX* process, the location, design,
and installation of tanks, piping, and other equipment or
chemicals associated with any pretreatment systems should be
considered. Pretreatment is often desired to remove oil and
grease, suspended solids, or metals. Any tanks that are part of
pretreatment or other support systems should be equipped with
vapor control devices (for example, floating lids) to prevent
VOC losses.
If on-site facilities are not available for office and laboratory
work, a small building or shed may be required near the
treatment process. The on-site building should be equipped
with electrical power to run laboratory equipment and should
be heated or air conditioned, depending on the climate. The
on-site laboratory should contain equipment needed for simple
analyses of the physical and chemical water characteristics
required to monitor performance. Such characteristics may
include pH, hydrogen peroxide dose, and temperature.
The CAV-OX* process is available in many sizes. During
the SITE demonstration, a 2,000-square-foot area was adequate
for both CAV-OX® configurations, support facilities,
nonhazardous and hazardous waste storage containers, and the
office and field laboratory trailer. A larger process may require
a slightly larger area, depending on the required support
facilities. Areas required for influent and effluent storage tanks
or pretreatment equipment, if needed, will depend on the number
and size of the tanks. Also, a 10-by-40-foot area may be required
for an office or laboratory building.
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The area containing the C AV-OX* process and tanks should
be relatively level and should be paved or covered with
compacted soil, gravel, or a concrete pad.
Site Access
Site access requirements for treatment equipment are
minimal. The site must be accessible to tractor-trailer trucks
of standard size and weight. The roadbed must be able to
support such a vehicle delivering the CAV-OX* equipment and
tanks.
Climate
According to Magnum, sub-freezing temperatures and heavy
precipitation do not affect the operation of the CAV-OX* process.
The process is designed to withstand rain and snow and does
not require heating or insulation because the chemical oxidation
process generates heat, increasing the water temperature.
However, if sub-freezing temperatures are expected for a long
period of time, chemical and influent storage tanks and associated
plumbing should be insulated or kept in a heated shelter, such as
a building or shed. Housing the process also facilitates regular
process checks and maintenance. The CAV-OX® process
requires a high-voltage power supply, which should also be
protected from heavy precipitation.
Utilities
Operation of the CAV-OX® process requires water and
electricity. Water is required for personnel and equipment
decontamination. The CAV-OX® I process requires 230-volt,
3-phase, 30-ampere electrical service. The CAV-OX® II process
requires 480-volt, single-phase, 30-ampere electrical service.
Additional 120-volt, single-phase, 10-ampere electrical service
is needed for UV power supply controls. The office and
laboratory trailer used for the SITE demonstration required 220-
volt, 3-phase, 50-ampere electrical service.
A telephone connection or cellular phone is required to order
supplies, contact emergency services, and provide normal
communications.
Services and Supplies
A number of services and supplies are required for operating
the CAV-OX* process, most of which can be readily obtained.
During the demonstration, subcontractors, off-site facilities, or
Edwards furnished the required major services.
An adequate on-site supply of spare parts is needed for
malfunction of UV lamps, pumps, flow meters, or piping. If
an on-site parts inventory is not an option, proximity to an
industrial supply center is an important consideration. In
addition, an adequate supply of chemicals, such as hydrogen
peroxide, or proximity to a supply center carrying this chemical,
is essential.
Complex laboratory services, such as VOC and SVOC
analyses that cannot usually be performed in an on-site field
laboratory, will require that a local analytical laboratory be
contracted with for ongoing monitoring.
Material Handling Requirements
The CAV-OX® process does not generate treatment residuals,
such as sludge or spent filter media, that require further
processing, handling, or disposal. The cavitation chamber, UV
reactor, control panel unit and other components of the process,
such as the chemical feed units, are air tight and produce no air
emissions that require special controls. Material handling
requirements for the CAV-OX* process include those for (1)
pretreatment materials and (2) treated water. These are described
below.
Pretreatment Materials
In general, pretreatment requirements for contaminated
water entering the CAV-OX* process are minimal. Depending
on the influent characteristics, pretreatment may involve one
or more of the following: oil and grease removal, suspended
solids removal, metals removal, or pH adjustment to reduce
carbonate and bicarbonate levels. These pretreatment
requirements are discussed below.
Water containing visible, free, or emulsified oil and grease
requires pretreatment to separate and remove the oil and grease.
If not treated, oil and grease will scale UV lamps and reduce
UV transmission, which adversely affects the oxidation process.
Separated oil and grease should be collected and analyzed to
determine disposal requirements.
Because suspended solids can also reduce UV transmission,
water containing more than 30 mg/L of suspended solids should
be pretreated. Depending on the concentration, cartridge filters,
sand filters, or settling tanks may be used to remove suspended
solids. Solids removed from the influent by pretreatment
precipitation, filtration, or settling should be dewatered,
containerized, and analyzed to determine whether they should
be disposed of as hazardous or nonhazardous waste.
Pretreatment also may be necessary for water containing
dissolved metals, such as iron and manganese. These metals
are likely to be oxidized in the CAV-OX® process and are less
soluble at higher oxidation states under alkaline conditions. After
oxidation, the metals will tend to precipitate as suspended solids
in the CAV-OX® process, resulting in UV lamp scaling.
Removing these metals is often advised; however, removal may
depend on the concentration of oxidizable metals in the
contaminated water. The economics of metals removal should
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be compared to predicted decreases in contaminant removal
efficiency without metals removal and the economics of more
frequent UV lamp cleaning or replacement. Metals removed
from the influent by precipitation should be containerized and
analyzed to determine whether they should be disposed of as
hazardous or nonhazardous waste.
If the contaminated water contains bicarbonate and carbonate
ions at levels greater than 400 mg/L as calcium carbonate, pH
may be adjusted in line. Carbonate and bicarbonate ions act as
oxidant scavengers and present an additional load to the treatment
process. The only material handling associated with pH
adjustment involves chemicals such as acids and bases; pH
adjustment will not create any additional waste streams requiring
disposal.
Treated Water
Treated water can be disposed of either on or off site.
Examples of on-site disposal options for treated water include
groundwater recharge or temporary on-site storage for sanitary
usage. Examples of off-site disposal options include discharge
into surface water bodies, storm sewers, and sanitary sewers.
Bioassay tests may be required in addition to routine chemical
and physical analyses before treated water is disposed of.
Depending on permit requirements and treatment process
operating conditions, treated water may require pH adjustment
before discharge.
Personnel Requirements
Personnel requirements for the CAV-OX* process are
minimal. Generally, one operator, trained by Magnum, conducts
a weekly 30-minute process check. The operator should be
able to: (1) fill the hydrogen peroxide feed tank and adjust
flow rates to achieve desired doses, (2) operate the control panel,
(3) collect liquid samples and perform simple physical and
chemical analyses and measurements (for example, pH,
hydrogen peroxide concentration, temperature, and flow rate),
(4) troubleshoot minor operational problems or conduct monthly
maintenance, and (5) collect samples for off-site analyses.
Analytical work requiring more technical skills, such as VOC
analyses and interpretation, can be performed by a local
laboratory. The frequency of sample collection and analysis
will depend on site-specific permit requirements.
Magnum reports that initial instruction to operate the
CAV-OX® process requires about 8 hours of training and 8 hours
of hands-on operation. The unit operator should also have
completed an Occupational Safety and Health Administration
(OSHA) initial 40-hour health and safety training course and an
annual 8-hour refresher course, if applicable, before operating
the CAV-OX* process at hazardous waste sites, and should
participate in a medical monitoring program, as specified under
OSHA requirements.
Potential Community Exposures
The CAV-OX® process generates no chemical or particulate
air emissions. Therefore, the potential for on-site personnel or
community exposure to airborne contaminants is very low. If
the process malfunctions, alarms will sound, and all process
components will shut off automatically. Contaminated-water
pumps can be hard wired to the control panel so that alarms
automatically stop flow through the unit, reducing the potential
for a contaminated water release.
Hydrogen peroxide solution, which is a reactive substance,
presents the greatest chemical hazard associated with the process.
However, when handled appropriately, the potential for exposure
to hydrogen peroxide by on-site personnel is low. Hydrogen
peroxide required for the CAV-OX® process is typically stored
in polyethylene totes housed in metal frames or cages. The
relatively small volumes of hydrogen peroxide that are used by
the process and secure chemical storage practices result in a
low potential threat of community exposure to hydrogen
peroxide.
Potential Regulatory Requirements
This subsection discusses regulatory requirements pertinent
to site remediation using the CAV-OX® process. Regulations
applicable to a particular application of this process will depend
on site-specific remediation logistics and the type of contaminated
water to be treated. Table 3 summarizes the potentially
applicable regulations that are discussed below.
Depending on the characteristics of the water to be treated,
pretreatment or posttreatment may be required for the successful
operation of the CAV-OX® process. For example, solids may
require prefiltering using cartridge filters, sand filters, or settling
tanks. Metals, such as iron and manganese, may require removal
by precipitation. Each pretreatment or posttreatment process
may have additional regulatory requirements that need to be
determined prior to use. This subsection focuses only on
regulations for the CAV-OX® process itself.
Comprehensive Environmental Response, Compensation, and
Liability Act
CERCLA, as amended by SARA, authorizes the federal
government to respond to releases into the environment of
hazardous substances, pollutants, or contaminants that may
present an imminent and substantial danger to public health or
welfare (Federal Register 1990a). Remedial alternatives that
significantly reduce the volume, toxicity, or mobility of
hazardous materials and provide long-term protection are
preferred. Selected remedies must also be cost effective and
protective of human health and the environment.
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Table 3. Regulations Summary
Act
Applicability
Application to the CAV-OX** Process
Citation
Comprehensive
Environmental
Response,
Compensation, and
Liability Act (CERCLA)
Resource
Conservation and
Recovery Act (RCRA)
Clean Water Act
(CWA)
Superfund sites
Superfund and RCRA sites
Discharges to surface
water bodies
Safe Drinking Water
Act (SDWA)
Toxic Substances
Control Act (TSCA)
Atomic Energy Act
(AEA) and RCRA
Polychlorinated biphenyl
(PCB) contamination
Mixed wastes
Federal Insecticide,
Fungicide, and
Rodenticide Act
(FIFRA)
Occupational Safety
and Health Act
(OSHA)
Pesticides
All remedial actions
The Superfund program authorizes and
regulates the cleanup of environmental
contamination. It applies to all CERCLA
site cleanups.
40 Code of Federal
Regulations (CFR) Part 300
40 CFR Parts 260 to 270,
Part 280
40 CFR Parts 122 to 125,
Part 403
Water discharges, water
reinjection, and sole-source
aquifer and wellhead
protection
40 CFR Part 141
RCRA defines and regulates the treatment,
storage, and disposal of hazardous wastes.
RCRA also regulates corrective action at
generator, treatment, storage, and disposal
facilities.
National Pollutant Discharge Elimination
Sysem (NPDES) requirements of CWA
apply to both Superfund and RCRA sites
where treated water is discharged to
surface water bodies. Pretreatment
standards apply to discharge to publicly
owned treatment works.
Maximum contaminant levels and
contaminant level goals should be
considered when setting water cleanup
levels at RCRA corrective action and
Superfund sites. (Water cleanup levels are
also discussed under CERCLA and
RCRA). Reinjection of treated water would
be subject to underground injection control
program requirements, and sole-source
and protected wellhead water sources
would be subject to their respective control
programs.
If PCB-contaminated wastes are treated,
TSCA requirements should be considered
when determining cleanup standards and
disposal requirements. RCRA also
regulates solid waste containing PCBs.
AEA and RCRA requirements apply to the
treatment, storage, and disposal of mixed
waste containing both hazardous and
radioactive components. Directives from
the Office of Solid Waste and Emergency
Response and the U.S. Department of
Energy provide guidance for addressing
mixed waste.
FIFRA regulates pesticide manufacturing
and labeling. However, if pesticide-
contaminated water is treated, RCRA
regulations apply.
OSHA regulates on-site construction and 29 CFR Parts 1900 to 1926
40 CFR Part 761
AEA and RCRA
40 CFR Part 165
the health and safety of workers at
hazardous waste sites. Installation and
operation of the process at Superfund or
RCRA sites must meet OSHA
requirements.
20 CFR Part 1910.120
(hazardous waste
operations and emergency
response)
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Contaminated water treatment using the CAV-OX* process
will generally take place on site, while treated water may be
discharged either on site or off site. On-site actions must meet
all substantive state and federal applicable or relevant and
appropriate requirements (ARAR). Substantive requirements
pertain directly to actions or conditions in the environment (for
example, effluent standards). Off-site actions must comply
with legally applicable substantive and administrative
requirements. Administrative requirements, such as permitting,
facilitate the implementation of substantive requirements.
EPA allows an ARAR to be waived for on-site actions. Six
ARAR waivers are provided by CERCLA: (1) interim measures
waiver, (2) equivalent standard of performance waiver, (3)
greater risk to health and the environment waiver, (4) technical
impracticability waiver, (5) inconsistent application of state
standard waiver, and (6) fund-balancing waiver. Justification
for a waiver must be clearly demonstrated (EPA 1988). Off-
site remediations are not eligible for ARAR waivers, and all
substantive and administrative applicable requirements must be
met.
Additional regulations pertinent to using the CAV-OX*
process are discussed below. No air emissions or residuals
(such as sludge or spent filter media) are generated by the
CAV-OX* process. Therefore, only regulations addressing
contaminated water treatment and discharge are presented.
Resource Conservation and Recovery Act
RCRA, as amended by the Hazardous and Solid Waste
Amendments of 1984, regulates management and disposal of
municipal and industrial solid wastes. The EPA and RCRA-
authorized states (listed in 40 Code of Federal Regulations [CFR]
Part 272) implement and enforce RCRA and state regulations.
The CAV-OX* process has been used to treat water contaminated
with a variety of organic materials, including solvents, herbicides,
polynuclear aromatic hydrocarbons, and petroleum
hydrocarbons. Contaminated water treated by the CAV-OX*
process will most likely be hazardous or sufficiently similar to
hazardous waste so that RCRA standards will be requirements.
Criteria for identifying hazardous wastes are included in 40 CFR
Part 261. Pertinent RCRA requirements are discussed below.
If the contaminated water to be treated is determined to be
a hazardous waste, RCRA requirements for storage and
treatment must be met. The CAV-OX* process may include
tank storage. Tank storage of contaminated and treated water
(if the waters are hazardous under RCRA) must meet the tank
storage requirements of 40 CFR Parts 264 or 265, Subpart J.
Although air emissions are not associated with the CAV-OX*
process, any fugitive emissions from storage tank vents would
be subject to forthcoming RCRA regulations (see 40 CFR Part
269) on air emissions from hazardous waste treatment, storage,
and disposal facilities. When promulgated, these requirements
will include standards for emissions from equipment leaks and
system vents. Treatment requirements included in 40 Part 265,
Subpart Q (Chemical, Physical, and Biological Treatment) would
also apply. This subpart includes requirements for automatic
influent shut-off, waste analysis, and trial tests.
The CAV-OX* process could also be used to treat
contaminated water at RCRA-regulated facilities. Requirements
for corrective action at RCRA-regulated facilities will be
included in 40 CFR Part 264, Subpart F (Regulated Units) and
Subpart S (Solid Waste Management Units), as well as 40 CFR
Part 280 (Underground Storage Tanks). These subparts also
will generally apply to remediation at Superfund sites. The
regulations include requirements for initiating and conducting
RCRA corrective actions, remediating groundwater, and
ensuring that corrective actions comply with other environmental
regulations (Federal Register 1990b).
Water quality standards included in RCRA (such as
groundwater monitoring and protection standards), the Clean
Water Act (CWA), and the Safe Drinking Water Act (SOWA)
would be appropriate cleanup standards and would apply to
discharges of treated water or reinjection of treated groundwater
(EPA 1989). The CWA and SDWA are discussed below.
Clean Water Act
The CWA is designed to restore and maintain the chemical,
physical, and biological quality of navigable surface waters by
establishing federal, state, and local discharge standards. If
treated water is discharged to surface water bodies or publicly
owned treatment works (POTW), CWA regulations will apply
to the discharge. On-site discharges to surface water bodies
must meet substantive National Pollutant Discharge Elimination
System (NPDES) requirements, but do not require an NPDES
permit. Off-site discharges to a surface water body require an
NPDES permit and must meet NPDES permit limits. Discharge
to a POTW is considered to be an off-site activity, even if an
on-site sewer is used. Therefore, compliance with substantive
and administrative requirements of the national pretreatment
program is required. General pretreatment regulations are
included in 40 CFR Part 403. Any local or state requirements,
such as state antidegradation requirements, must also be
identified and satisfied.
Safe Drinking Water Act
The SDWA, as amended in 1986, requires EPA to establish
regulations to protect human health from contaminants in
drinking water. EPA has developed the: (1) drinking water
standards program, (2) underground injection control program,
and (3) sole-source aquifer and wellhead protection programs
to achieve this objective.
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Under the SD WA, primary (or health-based) and secondary
(or aesthetic) MCLs and used as cleanup standards for water
that is, or may be, used for drinking water. In some cases,
such as when multiple contaminants are present, alternate
concentration limits (ACL) may be used. CERCLA and RCRA
standards and guidance should be used to establish ACLs (EPA
1987a).
Water discharge through injection wells is regulated by the
underground injection control program. Injection wells are
categorized as Class I through V, depending on their construction
and use. Reinjection of treated water involves Class IV
(reinjection) or Class V (recharge) wells and should meet
requirements for well construction, operation, and closure.
The sole-source aquifer protection and wellhead protection
programs are designed to protect specific drinking water supply
sources. If such a source is to be remediated using the CAV-OX*
process, appropriate program officials should be notified, and
any potential regulatory requirements should be identified. State
groundwater antidegradation requirements and water quality
standards may also apply.
Toxic Substances Control Act
Testing, premanufacture notification, and recordkeeping
requirements for toxic substances are regulated under the Toxic
Substances Control Act (TSCA). TSCA also includes storage
requirements for PCBs (40 CFR Part 761.65). The CAV-OX*
process may be used to treat water contaminated with PCBs;
PCB storage requirements would apply to pretreatment storage
of PCB-contaminated water. The SDWA MCL for PCBs is
0.5 ug/L; this MCL would generally be the treatment standard
for groundwater remediation at Superfund sites and RCRA
corrective action sites. RCRA land disposal requirements for
PCBs (see 40 CFR Part 268) may also apply, depending on
PCB concentrations. For example, liquid hazardous waste
containing PCB concentrations between 50 and 499 mg/L treated
by incineration or an equivalent method must meet the
requirements of 40 CFR Part 761.70.
Mixed Waste Regulations
Mixed waste contains both radioactive and hazardous
components, as defined by the Atomic Energy Act (AEA) and
RCRA, and is subject to the requirements of both acts. When
the application of both regulations results in a situation that is
inconsistent with the AEA (for example, an increased likelihood
of radioactive exposure), AEA requirements supersede RCRA
requirements. Use of the CAV-OX* process at sites with
radioactive contamination might involve the treatment or
generation of mixed waste.
The EPA OSWER, in conjunction with the Nuclear
Regulatory Commission, has issued several directives to assist
in the identification, treatment, and disposal of low-level
radioactive, mixed waste. Various OSWER directives include
guidance on defining, identifying, and disposing of commercial,
mixed, low-level radioactive and hazardous waste (EPA 1987b).
If the CAV-OX* process is used to treat low-level mixed wastes,
these directives should be considered. If high-level mixed waste
or transuranic mixed waste is treated, internal orders from the
U.S. Department of Energy (DOE) should be considered when
developing a protective remedy (DOE 1988).
Federal Insecticide, Fungicide, and Rodenticide Act
The CAV-OX* process can treat water contaminated with
pesticides. EPA regulates pesticide product sale, distribution,
and use through product licensing or registration under the
authority of the Federal Insecticide, Fungicide, and Rodenticide
Act (FIFRA) (see 40 CFR Part 165). Use of a pesticide product
in a manner inconsistent with its labeling violates FIFRA.
Compliance with FIFRA by following labeling directions may
not be required at Superfund or RCRA corrective action sites
because the pesticide may be a RCRA hazardous waste at that
point. In such cases, requirements for hazardous wastes
containing pesticide constituents must be met.
Occupational Safety and Health Administration
OSHA regulations, contained in 29 CFR Parts 1900 through
1926, are designed to protect worker health and safety. Both
Superfund and RCRA corrective actions must meet OSHA
requirements, particularly Part 1910.120, Hazardous Waste
Operations and Emergency Response. Part 1926, Safety and
Health Regulations for Construction, applies to any on-site
construction activities. For example, electric utility hookups
for the CAV-OX* process must comply with Part 1926, Subpart
K, Electrical. Product chemicals used with the CAV-OX*
process, such as hydrogen peroxide, must be managed in
accordance with OSHA requirements (for example, Part 1926,
Subpart D, Occupational Health and Environmental Controls,
and Subpart H, Materials Handling, Storage, and Disposal).
Any more stringent state or local requirements must also be
met.
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Section 4
Economic Analysis
This section presents cost estimates for using the CAV-OX®
process to treat groundwater containing VOCs. These cost
estimates are based on data compiled during the SITE
demonstration and provided by Magnum. Costs have been
placed in 12 categories applicable to typical cleanup activities
at Superfund andRCRA sites (Evans 1990). Costs are presented
in October 1993 dollars and are considered to be order-of-
magnitude estimates with an accuracy of plus 50 percent and
minus 30 percent.
Table 4 lists the costs associated with operating the
CAV-OX* I low-energy process. Table 5 lists the costs
associated with operating the CAV-OX* n high-energy process.
The tables present a breakdown of costs for the 12 cost categories
and compare the costs between high-energy and low-energy
configurations operating at flow rates of 10 and 25 gpm. Both
tables show (in boldface type) the costs directly associated with
using the CAV-OX* process. The tables also present total one-
time costs and total annual O&M costs; the total costs for a
hypothetical, 5-year groundwater remediation project; the net
present values of the project; and the costs per 1,000 gallons of
water treated. Each table concludes with a presentation of total
CAV-OX* direct one-time and annual O&M costs and the direct
costs per 1,000 gallons of water treated.
Basis of Economic Analysis
Several factors affect the estimated costs of treating
groundwater with the CAV-OX* process, including flow rate,
type and concentration of contaminants, groundwater chemistry,
physical site conditions, geographical site location, contaminated
groundwater plume size, and treatment goals.
The CAV-OX* process can treat several types of aqueous
wastes, including contaminated groundwater and industrial
wastewater. Contaminated groundwater was selected for this
economic analysis because it is commonly found at Superfund
and RCRA corrective action sites and because this waste
treatment scenario involves most of the cost categories. The
following discussion presents the assumptions and conditions
used in this analysis.
This analysis assumes that the CAV-OX* process will treat
contaminated groundwater continuously, 24 hours per day, 7
days per week. Based on this assumption, during a 1-year
period, the 10-gpm unit will treat about 5.3 million gallons,
and the 25-gpm unit will treat about 13.1 million gallons. This
analysis assumes that the treatment project will last 5 years for
both flow rate scenarios. In both configurations, the 10-gpm
flow rate will treat a total of 26.3 million gallons and the 25-
gpm flow rate will treat 65.7 million gallons of water. While it
is difficult in practice to determine both the volume of
groundwater for treatment and the actual duration of a project,
these figures are used in this economic analysis. In addition, a
5-year period was chosen for each flow rate scenario in order
to highlight the operating parameters and costs specific to treating
groundwater. It also shows the differences in the total volume
of water treated by using each flow rate. Standardizing the
time factor also standardizes all time-based costs (such as rental
equipment).
The total costs for a groundwater remediation project are
presented as future values. Using the period described above,
this analysis assumes a 5 percent inflation rate when calculating
annual O&M costs in order to estimate the total costs. The
future values are then presented as a net present value using a
discount rate of 5 percent. A higher discount rate will make
the initial costs weigh more heavily in the calculation, and a
lower discount rate will make the future operating costs weigh
more heavily. Because the costs of demobilization will occur
at the end of the project, the appropriate future values of those
costs presented in the tables were used in calculating the final
values. The costs per 1,000 gallons treated are derived from
the net present values. Capital equipment is not depreciated in
this economic analysis.
Assumptions about groundwater conditions and treatment
for both configurations and flow rate scenarios include the
following:
• Any suspended solids present in groundwater are
removed prior to entering the CAV-OX® process.
Hydrogen peroxide is the only feed chemical needed
and is used at a rate of 30 mg/L.
21
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Table 4. Costs Associated with the CAV-OX® I Low-Energy Process
Cost Categories
Estimated Costs (1993 $)
10gpm(a) 25gpm(a)
Site Preparation (b)
Administrative
Treatability Study
System Design
Mobilization
Permitting and Regulatory Requirements (b)
Capital Equipment (b)
Extraction Wells
Sheltered Concrete Pad
Treatment Equipment
Auxiliary Equipment
Startup (b)
Labor (c)
Operations Staff
Health and Safety Refresher Course
Consumables and Supplies (c)
Hydrogen Peroxide
UV Lamps
Cartridge Fitters
Carbon Columns
Personal Protective Equipment
Disposal Drums
Sampling Supplies
Utilities (c)
Treatment Process
Auxiliary Equipment
Effluent Treatment and Disposal (d)
Residual and Waste Shipping and Handling (c)
Analytical Services (c)
Maintenance and Modifications (c)
Treatment Process
Auxiliary Equipment
Demobilization (b)
Treatment Process
AllOther
Total One-rime Costs
Total Annual O&M Costs
Gnoundwater Remediation:
Total Costs (e,f,g)
Net Present Value (h)
Costs per 1,000 Gallons (g)
Total CA V-OX direct one-time costs
Total CAV-OX direct O&M costs (J)
Costs Per 1,000 Gallons-Direct Costs
NOTES:
Items in bold denote CAV-OX? process direct costs
a During a 1-year period, it is assumed the
and the 25-gpm unit will treat about 13. 1
b One-time costs
c Annual operation and maintenance costs
d Not applicable
e Future value
f Total for a 5-year project
g To complete a project within 5 years, it is
$74,700
35,000
2,000
33,700
4,000
15,725
314,500
145,000
22,500
48,000
98,000
5,000
34,000
31,000
3,000
4,760
900
1,000
200
1,000
600
60
1,000
1,430
1,300
130
0
4,000
24,000
2,920
960
1,960
40,000
10,000
30,000
$449,925
$71,110
$853,904
$799,595
$30
$69,000
$35,160
$10
35,000
2,000
36,100
4,000
158,000
22,500
64,000
98,000
31,000
3,000
2,200
3,700
200
1,000
600
60
1,000
3,600
360
1,280
1,960
10,000
30,000
$77,100
17,125
342,500
5,000
34,000
8,760
3,960
0
4,000
24,000
3,240
40,000
$481,725
$77,960
$923,555
$864,014
$13
$85,000
$41,780
$5
10-gpm unit will treat about 5.3 million gallons,
million gallons
assumed that the 10-gpm flow rate will treat a total
of 26.3 million gallons, and the 25-gpm flow rate will treat a total of 65.7 million gallons
h Annual discount rate of 5 percent
j Administrative, permitting, etc. are not considered a direct O&M cost for the process
22
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Table S. Costs Associated with the CAV-OX* II High-E\ergy Process
f
Cost Categories
Estimated Costs (19931)
10gpm(a) 25gpm(a)
Site Preparation (b)
Administrative
Instability Study
System Design
Mobilization
Permitting and Regulatory Requirements (b)
Capital Equipment (b)
Extraction Wells
Sheltered Concrete Pad
Treatment Equipment
Auxiliary Equipment
Startup (b)
Labor (c)
Operations Staff
Health and Safety Refresher Course
Consumables and Supplies (c)
Hydrogen Peroxide
UV Lamps
Cartridge Filters
Carbon Columns
Personal Protective Equipment
Disposal Drums
Sampling Supplies
Utilities (c)
Treatment Process
Auxiliary Equipment
Effluent Treatment and Disposal (d)
Residual and Waste Shipping and Handling (c)
Analytical Services (c)
Maintenance and Modifications (c)
Treatment Process
Auxiliary Equipment
Demobilization (b)
Treatment Process
AllOther
Total One-Time Costs
Total Annual O&M Costs
Groundwater Remediation:
Total Costs (e,f,g)
Net Present Value (h)
Costs per 1,000 Gallons (g)
Total CAV-OX direct one-time costs
Total CAV-OX direct O&M costs (j)
Costs per 1,000 Gallons-Direct Costs
NOTES:
Items in bold denote CAV-OX* process direct costs
a During a 1-year period, it is assumed the
and the 25-gpm unit will treat about 13. 1
b One-time costs
c Annual operation and maintenance costs
d Not applicable
e Future value
f Total for a 5-year project
g To complete a project within 5 years, it is
35,000
2,000
33,700
4,000
146,000
22,500
48,000
98,000
31,000
3,000
900
500
200
1,000
600
60
1,000
5,500
550
960
1,960
10,000
30,000
10-gpm unit will
million gallons
$74,700
15,725
314,500
5,000
34,000
4,260
6,050
0
4,000
24,000
2,920
40,000
$449,925
$75,230
$876,670
$819,214
$31
$69,000
138,860
$11
35,000
2,000
36,100
4,000
158,000
22,500
64,000
98,000
31,000
3,000
2,200
1,400
200
1,000
600
60
1,000
13,200
1,300
1,280
1,960
10,000
30,000
treat about 5.3 million gallons,
$77,100
17,125
342,500
5,000
34,000
6,460
14,500
0
4,000
24,000
3,240
40,000
$481,725
$86,200
$969,086
$903,252
$14
$85,000
$49,080
$5
assumed that the 10-gpm flow rate will treat a total
of 26.3 million gallons, and the 25-gpm flow rate will treat
h Annual discount rate of 5 percent
j Administrative, permitting, etc. are not considered a direct
a total of 65.7 million gallons
O&M cost for the process
23
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• Alkalinity is not a concern because scaling does not
occur within the CAV-OX* process.
The treated effluent has a pH between 6.5 and 8.5 and
will not require posttreatment to meet discharge
standards.
The groundwater contains negligible amounts of iron
and manganese and will not require pretreatment for
metals.
This analysis assumes that treated water will be discharged
to surface water, and that the MCLs specified in the SDWA
are the treatment target levels. Based on results of the SITE
demonstration, the CAV-OX® process should achieve these
levels.
The following assumptions were also made in this analysis:
The site is a Superfund site in a semirural area of
California.
Contaminated water is in an aquifer requiring 150-foot
extraction wells.
• Suitable site access roads exist.
All required utility lines (such as electricity and
telephone) exist on site.
• A 900-square-foot concrete pad with an awning will
be needed to site and shelter the treatment process and
auxiliary equipment for both configurations and both
flow rate scenarios.
• The treatment process operates automatically.
One technician will be required to operate the
equipment, collect all required samples, and maintain
and repair equipment.
Labor costs associated with major repairs are not
included.
Treated and untreated water samples will be collected
monthly and analyzed off site for VOCs.
Disposal costs for spent UV lamps from the CAV-OX®
process are incurred by the customer.
Estimates of the chemical feed rates and the hydraulic
retention time required to meet treatment goals, which are listed
in Appendix B, are based on the CAV-OX® process's
performance during pilot tests, and on discussions with Magnum.
On the basis of the demonstration, VOCs in the groundwater
are assumed to be TCE at 1,100 ug/L and benzene at 250 ug/L.
Cost Categories
Cost data associated with the CAV-OX® process have been
assigned to the following 12 categories: (1) site preparation,
(2) permitting and regulatory requirements, (3) capital
equipment, (4) startup, (5) labor, (6) consumables and supplies,
(7) utilities, (8) effluent treatment and disposal, (9) residuals
and waste shipping and handling, (10) analytical services,
(11) maintenance and modifications, and (12) demobilization.
Costs associated with each category are presented in the sections
that follow. All direct costs associated with operating the
CAV-OX® process are identified as CAV-OX® direct costs; all
costs associated with the hypothetical remediation and auxiliary
equipment are identified as groundwater remediation costs.
Site Preparation Costs
Site preparation costs include administrative, treatability
study, process design, and mobilization costs. For this analysis,
administrative costs, such as legal searches, access rights, and
other site planning activities, are associated with a groundwater
remediation project and are estimated to be $35,000.
A treatability study will be needed to determine the
appropriate specifications of the CAV-OX® process for the site
as well as the amounts of chemicals and reagents needed for
optimal performance. Magnum, which will perform this study,
estimates that a typical study will cost about $2,000.
Process design costs include those for the site layout and
the treatment process operations, and are associated with a
groundwater remediation project. Design costs are typically
20 percent of the total construction cost. Construction costs
include constructing a concrete pad and shelter for the treatment
and auxiliary equipment and installing extraction wells and piping
(see Capital Equipment Costs). Construction costs are about
$ 168,500 for the 10-gpm flow rate scenario and about $ 180,500
for the 25-gpm flow rate scenario for both configurations.
Therefore, design costs would be about $34,000 for the 10-
gpm flow rate and about $36,000 for the 25-gpm flow rate for
both configurations.
Mobilization involves transporting all equipment to the site,
assembling the equipment, performing optimization and
shakedown activities, and training an operator. Transportation
costs are site-specific and will depend on the location of the site
in relation to all equipment vendors. The CAV-OX® process is
delivered to each site in one semitrailer from El Segundo,
California, and is estimated to cost $ 1,000. Magnum will position
the process, but the customer is responsible for making all
necessary connections and performing all optimization and
shakedown activities. Initial operator training is needed to ensure
24
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safe, economical, and efficient operation of the process.
Magnum estimates that training will require about 1 day. Total
mobilization costs are estimated to be about $4,000, and
mobilization is estimated to take about 5 days to complete,
regardless of flow rate or treatment process size.
For both configurations, total site preparation costs are
estimated to be about $75,000 for the 10-gpm flow rate scenario
and $77,000 for the 25-gpm flow rate scenario.
Permitting and Regulatory Requirements Costs
Permitting and regulatory costs depend on whether treatment
is performed at a corrective action site regulated under Superfund
or RCRA and disposal methods for treated effluent and solid
waste. Superfund sites require remedial actions to be consistent
with ARARs of environmental laws, ordinances, regulations,
and statutes, including federal, state, and local standards and
criteria. In general, ARARs must be determined on a site-
specific basis. RCRA corrective action sites require additional
monitoring records and sampling protocols, which can increase
the permitting and regulatory costs by an additional 5 percent.
Permitting and regulatory costs associated with a
groundwater remediation project are assumed to be about 5
percent of the total capital equipment costs for a treatment
operation that is part of a Superfund site remediation project.
This estimate does not include annual discharge permit costs,
which may vary significantly depending on state and local
requirements.
For both configurations, permitting and regulatory costs
are estimated to be $16,000 for the 10-gpm flow rate scenario
and $17,000 for the 25-gpm flow rate scenario.
Capital Equipment Costs
Capital equipment costs include installing extraction wells;
constructing a concrete pad and shelter for the treatment and
auxiliary equipment; and purchasing all treatment and auxiliary
equipment.
Extraction well installation costs are associated with a
groundwater remediation project and include installing the well
and pump and connecting the pumps, piping, and valves from
the wells to the CAV-OX® process. This analysis assumes that
four, 150-foot extraction wells will be required to maintain the
flow rate in each scenario. Extraction wells can be installed at
about $150 per foot per well. Total well construction costs for
both configurations and flow rate scenarios will be about
$90,000.
Pumps, piping, and valve connection costs are associated
with a groundwater remediation project and will depend on the
number of extraction wells needed, the flow rate, the distance
of the extraction wells from the treatment process, and the
climate of the area. This analysis assumes that four extraction
wells are located about 200 feet from the CAV-OX® process.
Four 2.5-gpm pumps will be required to maintain a 10-gpm
flow rate. The total cost for four 2.5-gpm pumps is about
$8,000. Four 6.25-gpm pumps will be required to maintain a
25-gpm flow rate; the total cost of four 6.25-gpm pumps is
about $20,000. Piping and valve connection costs, including
Installation, are about $60 per foot. Therefore, total piping
costs are estimated to be an additional $48,000.
The total cost of constructing extraction wells and all
connections will be about $146,000 for the 10-gpm flow rate
scenario and $158,000 for the 25-gpm flow rate scenario for
both configurations.
A concrete pad with an awning will need to be constructed
to shelter the CAV-OX® process and all auxiliary equipment.
The concrete pad will measure about 900 square feet and will
cost about $25 per square foot, including construction and
materials, for a total cost of $22,500. Costs associated with
designing the concrete pad are included in the process design
costs (see Site Preparation Costs). Total construction costs for
both configurations will be about $ 168,500 for the 10-gpm flow
rate scenario and about $180,500 for the 25-gpm flow rate
scenario for both configurations.
Treatment equipment typically consists of the CAV-OX®
process and a 500-gallon hydrogen peroxide chemical feed
module equipped with two feed pumps. The cost of the hydrogen
peroxide module is included in the cost of the treatment process
equipment. The cost of the CAV-OX* process will vary
depending on the size of the required unit. Magnum identifies
unit sizes by UV lamp kW demand. The wattage required
depends on flow rates and the contaminants present in the water.
For this analysis, the CAV-OX® I low-energy process operating
at 10 gpm will require a unit with twelve 60-watt lamps available
at a cost of $48,000. The CAV-OX® I process operating at 25
gpm will require a unit with forty-eight 60-watt lamps available
at a cost of $64,000. The CAV-OX® II high-energy process
operating at 10 gpm will require a unit with one 7.5-kW lamp
available at a cost of $48,000. The CAV-OX* II process
operating at 25 gpm will require a unit with one 20-kW lamp
available at a cost of $64,000. Lamp wattage is estimated based
on the flow through the process.
For this analysis, auxiliary equipment associated with a
groundwater remediaiion project includes one sedimentation
tank, two equalization tanks, two cartridge filters, and one filter
press. This auxiliary equipment will be the same for both flow
rate scenarios and treatment process configurations. One 2,000-
gallon sedimentation tank will be located downstream of the
extraction wells and upstream of the cartridge filters to allow
solids to settle out before treatment. This tank costs about
$5,000. Two 5,000-gallon equalization tanks are needed to
minimize fluctuations in VOC concentrations. While one tank
is being filled, the other will be emptied. These tanks will be
25
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located downstream of the cartridge filters. Both equalization
tanks will cost a total of about $14,000. All tanks used during
the remediation are assumed to have closed tops with vents. A
venting process that includes ductwork and carbon columns will
be needed to eliminate fugitive emissions from the tanks. This
venting process will cost about $25,000.
For this analysis, filtration will be required to remove any
suspended solids from the sedimentation tank effluent. Two
cartridge filters will be installed on the CAV-OX* feed line.
Cartridges cost about $2,000 each for the 10- and 25-gpm flow
rate scenarios, for a total cost of $4,000. The costs of
replacement filters are included in Consumables and Supplies
Costs.
A filter press will be needed to dewater the sediment
collected in the sedimentation tank and any other tanks that
may accumulate sediment. The size of the filter press will be
determined after a bench-scale study is performed. This analysis
assumes that a 4-cubic-foot filter press will be used, at a cost of
about $50,000.
Total auxiliary equipment costs, including venting ductwork,
for both configurations and both flow rate scenarios will be
about $98,000.
Startup Costs
Startup costs include the cost of developing a health and
safety program, which will also include providing a 40-hour
health and safety training course. The startup cost associated
with a groundwater remediation project is estimated to be about
$5,000 for both flow rate scenarios and both configurations.
Labor Costs
Labor costs include the total staff needed for operating and
maintaining the CAV-OX* process, conducting an annual health
and safety refresher course, and medical monitoring. The labor
wage rates provided in this analysis do not include overhead or
fringe benefits. Once the process is functioning, it is assumed
to operate continuously at the designed flow rate, except during
routine maintenance. One operator will monitor the equipment,
make any required hydrogen peroxide dose adjustments, and
perform routine maintenance, monitoring, and sample analysis.
Magnum estimates that under normal operating conditions, an
operator will be required to spend only 100 hours per year at
the treatment site, excluding travel time. However, because
finding a person willing to work for this short period may be
difficult, this analysis assumes that the operator will work 8
hours during the weekdays. Annual labor costs for each
treatment process and flow rate scenario are calculated using a
52-week year at a rate of $15 per hour for a total of about
$31,000. An annual health and safety refresher course and
medical monitoring are associated with a groundwater
remediation project and will cost about $3,000 per person. Total
annual labor costs will be about $34,000.
Consumables and Supplies Costs
Consumables and supplies costs fall into two major
categories: (1) consumables and supplies associated with the
operation of the CAV-OX* process (hydrogen peroxide,
cartridge filters, activated carbon columns, and UV lamps) and
(2) consumables and supplies associated with personal protective
equipment (PPE), waste disposal, and sampling supplies.
Hydrogen peroxide is commercially available in solutions
of 30 to 50 percent by weight. It can be purchased in bulk,
delivered to the site when needed, and stored in a 500-gallon
tank (see Capital Equipment Costs). Hydrogen peroxide has a
shelf life of over 1 year and a density of about 10 pounds per
gallon. The quantities of hydrogen peroxide consumed depend
on the process flow rate and the waste characteristics. A 50
percent solution can be purchased for about $0.33 per pound
including delivery. For this analysis, the hydrogen peroxide
dose for both configurations and both flow rate scenarios will
be 30 mg/L. This dosage requires 2,630 pounds of 50 percent
hydrogen peroxide solution annually for the 10-gpm flow rate
scenario for both configurations for a total cost of about $900.
Annual hydrogen peroxide solution consumption for the 25-
gpm flow rate scenario for both configurations would be 6,570
pounds for a total cost of about $2,200.
This analysis assumes that two cartridge filters capable of
screening material larger than 3 microns will be installed
upstream of the CAV-OX* unit and downstream of the
sedimentation tank. The dual filter process allows one filter to
be used while the other is replaced. These filters should remove
any suspended solids prior to treatment. Replacement frequency
depends on the quality of the groundwater to be treated and the
flow rate. This analysis assumes that one replacement filter
will be needed every 3 months. For both configurations and
both flow rate scenarios, replacement filters will cost about
$50 each or $200 per year.
Activated carbon columns on the venting system for the
sedimentation and equalization tanks are assumed to require
replacement every 6 months and are associated with a
groundwater remediation project. Replacement columns cost
about $500 each, for a total of $1,000 per year. The actual rate
at which these carbon columns will need replacement depends
on the concentrations of VOCs in the water being treated.
Mercury-vapor UV lamps are used in the CAV-OX* process.
Magnum recommends replacing UV lamps after every 7,500
hours of use in the CAV-OX* I low-energy process and every
2,000 hours of use in the CAV-OX* II high-energy process. At
this rate, lamps in the CAV-OX® I process will need to be changed
about every 10 months, and those in the CAV-OX® II process
will need to be changed every 3 months. The CAV-OX* I process
uses 12 UV lamps in the 10-gpm flow rate unit and 48 UV
26
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lamps in the 25-gpm flow rate unit. Low-energy UV lamps cost
$65 each. Therefore, the annual cost of UV lamps for the
CAV-OX* I process will be about $1,000 for the 10-gpm flow
rate scenario and $3,700 for the 25-gpm flow rate scenario.
The CAV-OX® II process uses one 7.5-kW lamp in the 10-gpm
flow rate unit, which costs $120, and one 20-kW lamp in the
25-gpm flow rate unit, which costs $350. Total lamp costs for
the CAV-OX* II process will be about $500 for the 10-gpm
flow rate scenario and $1,400 for the 25-gpm flow rate scenario.
PPE associated with a groundwater remediation project
typically consists of nondisposable and disposable equipment.
Nondisposable equipment consists of steel-toe boots and a full-
face air respirator. Disposable PPE includes latex inner gloves,
nitrile outer gloves, and safety glasses. Disposable PPE is
assumed to cost about $600 per year for the operator, for both
configurations and both flow rate scenarios.
Used UV lamps and disposable PPE are assumed to be
hazardous and will need to be disposed of in 24-gallon drums.
Any other potentially hazardous non-liquid wastes will also be
disposed of in these drums. One drum is assumed to be filled
every 3 months regardless of configuration or flow rate. Drums
cost about $15 each, bringing the total annual drum cost to
about $60.
Sampling supplies are associated with a groundwater
remediation project and consist of sampling bottles and
containers, ice, labels, shipping containers, and laboratory forms
for off-site analyses. For routine monitoring, laboratory
glassware will also be needed. The number and types of
sampling supplies will be based on the analyses to be performed.
For this analysis, the cost of sampling supplies is assumed to be
$ 1,000 per year. Costs for laboratory analyses are presented in
the Analytical Services Costs section.
Utilities Costs
Total utility costs are based on the electrical power used to
operate the entire treatment process and all auxiliary equipment.
The mercury-vapor UV lamps and pumps draw the majority of
electricity used by the CAV-OX® process; that usage is presented
in this analysis, which assumes that electricity costs about $0.07
per kW hour (kWh), inclusive of usage and demand charges.
This analysis also assumes that all auxiliary equipment will draw
an additional 10 percent of the total electrical power of the
CAV-OX* process being used.
The CAV-OX* I low-energy process operating at 10 gpm
draws about 2.2 kW, for a total annual cost of about $1,300.
Operating at 25 gpm, it draws about 5.9 kW for a total annual
cost of about $3,600. The CAV-OX* II high-energy process
operating at 10 gpm draws about 9 kW, for a total annual cost of
about $5,500. Operating at 25 gpm, it draws about 21.5 kW for
a total annual cost of about $13,200.
Auxiliary equipment usage will cost an additional $130 for
the 10-gpm CAV-OX* I process; $360 for the 25-gpm CAV-OX*
I process; $550 for the 10-gpm CAV-OX* II process; and $1,300
for the 25-gpm CAV-OX* II process.
Electrical costs can vary by as much as 50 percent depending
on the geographical location and local utility rates. A diesel-
powered generator can also be used as a backup or alternate
source of electric power, but it will cost considerably more
than similar power supplied by local utilities.
Effluent Treatment and Disposal Costs
The CAV-OX* process does not generate sludge or spent
carbon that requires further processing, handling, or disposal.
Ideally, the products of the process are water, carbon dioxide,
and sometimes organic acids. Effluent will be monitored
routinely by the operator (see Labor Costs), and can be
discharged directly to a nearby surface water body or POTW,
assuming that the appropriate permits have been obtained (see
Permitting and Regulatory Requirements Costs). This analysis
assumes that no effluent treatment and disposal costs are
incurred.
Residuals and Waste Shipping and Handling Costs
Spent cartridge filters, disposable PPE, and used UV lamps
are generated from using the CAV-OX* process. These wastes
are considered hazardous and will require disposal at a permitted
facility. This analysis assumes that about four drums will be
disposed of annually for both configurations, regardless of flow
rate. The cost of shipping, handling, and transporting drums to
a hazardous waste disposal facility are assumed to be $1,000
per drum. Total drum disposal costs will be about $4,000.
In addition, filter cake from the filter press is considered a
hazardous waste and will require disposal at a permitted facility.
Because the amount of filter cake generated will vary greatly
from site to site, this analysis does not present the costs of filter
cake disposal.
Analytical Services Costs
Analytical costs associated with a groundwater remediation
project include laboratory analyses, data reduction and
tabulation, quality assurance and quality control (QA/QC), and
reporting. This analysis assumes that one sample of untreated
water and one sample of treated water will be analyzed for
VOCs each month along with trip blank, duplicate, and matrix
spike/matrix spike duplicate samples. Monthly laboratory
analyses will cost about $ 1,250; data reduction, tabulation, QA/
QC, and reporting is estimated to cost about $750 per month.
Total annual analytical services costs are estimated to be about
$24,000 for both configurations and both flow rate scenarios.
27
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Maintenance and Modifications Costs
Annual repair and maintenance costs apply to all equipment
involved in every aspect of groundwater remediation with the
CAV-OX® process. No modification costs are assumed to be
incurred. Magnum estimates that total annual maintenance costs
will be about 2 percent of treatment process and auxiliary
equipment costs. Maintenance costs are estimated at $3,000
for both configurations and both flow rate scenarios.
Demobilization Costs
This analysis assumes that site demobilization will include
shutdown, disassembly, transportation, and disposal of
CAV-OX* equipment and auxiliary equipment at a licensed
hazardous waste disposal facility. This analysis also assumes
that the CAV-OX* process will have no salvage value at the end
of the project. Site clean up and restoration are also included in
demobilization costs. This analysis assumes that the costs from
shutdown to disposal for all activities associated with a
groundwater remediation project will be about $30,000,
including site clean up, restoration, and equipment
decontamination. All disposal activities associated with
operating the CAV-OX® process are estimated to cost an
additional $10,000. Demobilization is estimated to take about
1 week to complete and to cost about $40,000.
The costs of demobilization, however, will be incurred at
the end of the remediation project. This analysis assumes that
the equipment will be used for 5 years, regardless of flow rate.
Assuming an annual inflation rate of 5 percent, the net future
value of this cost is estimated to be about $51,051. This figure
was used to calculate the total costs presented in Tables 4 and 5.
References
Evans, G. 1990. "Estimating Innovative Technology Costs for
the SITE Program." Journal of Air and Waste
Management Association. Volume 40, No. 7. My.
Federal Register. 1 990a. U. S. Environmental Protection Agency,
National Oil and Hazardous Substances Pollution
Contingency Plan. Final Rule. Volume 55, No. 46.
March 8.
Register. 1990b. EPA Proposed Rules for Corrective
Action for Solid Waste Management Units at Hazardous
Waste Management Facilities Volume 55, No. 145.
July 27.
Flint, E. B. and Suslick, K. S. 1991. "The Temperature of
Cavitation." Science. Volume 253. September 20.
Glaze, W., and others. 1987. "The Chemistry of Water
Treatment Systems Involving Ozone, Hydrogen
Peroxide, and Ultraviolet Radiation." Ozone Science
and Engineering. Vol.9.
Suslick, K. S. 1989. "The Chemical Effects of Ultrasound."
Scientific American. February.
U.S. Department of Energy (DOE). 1988. Radioactive Waste
Management Order. DOE Order 5820.2 A. September
26.
U.S. Environmental Protection Agency (EPA). 1987a. Alternate
Concentration Limit (ACL) Guidance. Parti: ACL
Policy and Information Requirements. EPA/530/SW-
87/017.
EPA. 1987b. Joint EPA-Nuclear Regulatory Agency Guidance
on Mixed Low-Level Radioactive and Hazardous
Waste. OSWER Directives 9480.00-14 (June 29).
9432.00-2 (January 8), and 9487.00-8 (August 3).
EPA. 1988. "Protocol for a Chemical Treatment Demonstration
Plan." Cincinnati, Ohio.
EPA. 1989. EPA Memorandum from OSWER to Waste
Management Division and Office of Regional Counsel.
Applicability of Land Disposal Restrictions to RCRA
and CERCLA Groundwater Treatment Reinjection.
Superfund Management Review. Recommendation
No. 26. December 27.
28
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Appendix A
Vendor's Claims for the Technology
Note: This appendix to the report is provided entirely by
Magnum Water Technology (Magnum). Claims and
interpretations are made by Magnum and have not
necessarily been substantiated by test data. This appendix
has been edited only so that format is consistent with the
document.
Introduction
Advanced oxidation systems have been used in various forms
for many years to treat both industrial waste effluents and
groundwater. A major benefit of advanced oxidation over
conventional water treatment methods is its ability to reduce a
variety of contaminants without producing by-products or
transferring the contaminants to another medium requiring
additional treatment or disposal.
In the past, ultraviolet (UV) radiation was combined with
other oxidants, such as ozone, to achieve efficient reduction of
contaminants at a more reasonable operating cost. The
C AV-OX® process combines a patented cavitation chamber with
hydrogen peroxide and UV radiation. The cavitation chamber
is designed based on the principle of hydrodynamic cavitation,
making the advanced oxidation process low maintenance and
more cost-effective.
This appendix describes Magnum's experience in developing
and applying the principles of hydrodynamic cavitation in
combination with advanced oxidation for the treatment of
industrial effluents and groundwater.
Hydrodynamic Cavitation
Physical Process
When a body of liquid is heated under constant pressure, or
when its pressure is reduced at constant temperature by static
or dynamic means, vapor-filled microbubbles (vapor and gas),
or cavities, grow and ultimately become visible. This condition
is called "boiling" if it is caused by temperature rise and
"cavitation" if it is caused by dynamic pressure reduction at
constant temperature. Cavitation involves the entire sequence
of events beginning with bubble formation through cavity
collapse.
Cavitation is very useful in the breakdown of organic
chemicals and living organisms. In cavitated water, the heat
from cavity implosion decomposes water into extremely reactive
hydrogen atoms and hydroxyl radicals. During the immediate
cooling phase, hydrogen atoms and hydroxyl radicals (OH-)
recombine to form hydrogen peroxide, H2O2, and molecular
hydrogen, H2. If other compounds are added to the water, a
wide range of secondary reactions can occur. Organic
compounds are highly degraded in this environment, and
inorganic compounds can be oxidized or reduced (Suslick 1989).
Recent experiments have shown the temperature and pressure
of the bubble collapse to be 5,000 degrees Kelvin (°K) and
1,000 atmospheres, respectively.
Cavitation is thus a result of pressure reductions in liquid
and can be affected by controlling the pressure reduction. If
the pressure is reduced and maintained long enough below a
certain critical pressure, determined by the physical properties
and conditions of the liquid, cavitation will result.
Dwell time is an integral part of cavitational flow,
particularly for cavitation only operation. Dwell time is the
period of time which the contaminant flow from the cavitation
chamber is allowed to pause in dwell tanks, thereby enabling
the micro bubble collapse process and the chemical dissociation
mechanism to continue toward completion. After the dwell
tank, the fluid stream is pumped back through the cavitation
chamber for recycling, or is pumped forward into further
processing. When the processing includes a UV reactor, then
the process stream is pumped into the downstream UV reactor
for further oxidation. Dwell tank time delay is a function of (1)
the volume of the dwell tank, (2) the flow rate, and (3) the
proportion of flow through the dwell tank.
29
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The residence time of the process stream in the UV reactor
is also a parameter in the management of the process stream.
Residence time is the period required for a specific component
of the contaminant stream to move into and out of the UV
reactor. Residence time directly affects the amount of UV
radiation received by each specific component of the contaminant
stream. Residence time is allowed to vary from 1 minute to 20
minutes in the operating protocols. Generally, residence time
is a direct function of the volume of the UV reactor divided by
the flow in gallons per minute. Residence time can be directly
affected by the amount of cavitation recycle being used, which
is controlled by the recycle valve setting.
Chemical Process
The chemistry involved in the CAV-OX* process is based
on the formation of hydroxyl radicals. The hydroxyl radical,
OH«, one of the simplest diatomic radicals, is a powerful
oxidizing agent as well as an excellent initiator for chain
reactions. The standard oxidation electrode potential for the
hydroxyl radical is 2.8 volts, while that of ozone is 2.18 volts,
and that of chlorine is 1.68 volts. As a result, the hydroxyl radical
more efficiently and rapidly oxidizes organics in water than either
ozone or chlorine.
A hydroxyl radical initiates a chain reaction through many
paths. The predominant route is the removal of an unstable
hydrogen atom from an organic molecule. The attack on a
glucose molecule by a hydroxyl radical is a typical example of
these mechanics. The conversion of a glucose molecule into
carbon dioxide and water begins when a hydroxyl radical
removes a hydrogen atom from a glucose molecule. In the
presence of air, the resulting glucose radical readily combines
with an oxygen molecule to form a peroxy-glucose radical that
in turn removes a hydrogen atom from another glucose molecule.
This reaction results in a new glucose radical and a hydrogen
peroxide molecule. The hydrogen peroxide molecule
disassociates easily into an oxy-glucose radical, and a hydroxyl
radical is regenerated. In the presence of oxygen, the oxy-glucose
radical leads to the formation of a smaller organic radical, which
continues to break down into oxalic acid and eventually to carbon
dioxide and water.
With more complex molecules, competing reactions occur
between the attack on the unstable hydrogen atom and the
addition of the double bond. For example, minor amounts of
intermediate molecules, such as catechol, hydroxyquinone,
muconic acid, maleic acid, and oxalic acid are produced during
the photo-oxidation of phenol. Reactions producing these
molecules are typical of compounds that are difficult to oxidize.
The sonochemistry resulting from optimum cavitation is
disclosed in the following articles: "Sonochemistry," K. S.
Suslick, Science, March 23, 1990, Volume 247, pages 1439-
1445, and an article entitled "The Temperature of Cavitation,"
E. B. Flint and K. S. Suslick, Science, September 20, 1991,
Volume 253, pages 1397-1399.
Technology Description
The CAV-OX® process is a synergistic combination of
hydrodynamic cavitation and UV radiation that oxidizes
contaminants in water. It is a cost-effective method of removing
organic contaminants from aqueous waste streams or
groundwater without releasing volatile organic compounds
(VOC) or producing material requiring further treatment. The
process can reduce contaminant levels to meet discharge
requirements for most aqueous solutions.
The complete CAV-OX* process consists of either the
CAV-OX® I low-energy process or the CAV-OX* II high-energy
process. The CAV-OX* I process effectively treats contaminants
such as gasoline or trichloroethene, while more complex wastes,
such as pentachlorophenol (PCP), require the use of the
CAV-OX* II process.
The CAV-OX® process generally reduces contaminant levels
by 95 to 99.99 percent. It cannot treat free product nor badly
turbid waste streams because the UV reactors are less efficient
because of lowered UV transfer to the waste stream; however,
free product or turbid waste streams do not affect the cavitation
chamber.
The CAV-OX* process oxidizes organic wastes into carbon
dioxide through a free radical mechanism. Free radicals are
generated and maintained by the combination of cavitation,
seeding with hydrogen peroxide, metal catalysts, and ultraviolet
light excitation. If required, reaction initiators are added to the
water before entering the cavitation chamber. The oxidation
process begins in the cavitation chamber; it continues in the UV
reactor and persists long after the treated water leaves the process
until there is no surplus of oxidants. Part or all of the waste
streams can be recycled after cavitation, after UV oxidation, or
after a combination of the two.
During oxidation, organic carbon is converted to carbon
dioxide and sulfides are converted to sulfates. No solids are
generated. The treated waste stream is low in organics and is
disinfected by the UV light and carbon transition. It can be
reused, discharged into local sewage facilities, or discharged
directly into local waterways, depending on local discharge
requirements and process design.
Operational parameters are varied during the treatment
process to achieve desired treatment efficiencies. Such
parameters include hydraulic retention time, hydrogen peroxide
dose, UV lamp intensity, and influent pH. In general, increasing
retention time increases treatment efficiency.
30
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If present in excess, hydrogen peroxide can act as a free
radical scavenger, decreasing the hydroxyl radical concentration.
Therefore, the minimum dose of hydrogen peroxide that achieves
the required treatment is preferred.
The CAV-OX* process tends to oxidize metallic salts;
however, both the CAV-OX* I and CAV-OX* II UV lamps
generate minimal heat and have shown no scaling tendencies.
Contaminants Treated by the CA V-OX" Process
The CAV-OX* process has been used to treat the following
contaminants:
• Atrazine
• Chlorinated organics
Halogenated organics
• Petroleum hydrocarbons
Pesticides and herbicides
Polychlorinated biphenyls (PCB)
Polynuclear aromatic hydrocarbons (PAH)
• Benzene, toluene, ethylbenzene, and xylenes (BTEX)
Cyanides
Phenol
Bacteria
• Viruses
The CAV-OX* process can treat the following contaminants in
industrial wastewater:
Amines
Aniline
• Chlorinated solvents
Chlorobenzene
• Complex cyanides
• Creosote
• Hydrazine compounds
Isopropanol
Methyl ethyl ketone (MEK)
Methyl isobutyl ketone (MffiK)
Methylene chloride
• PCBs
• PCP
• Pesticides
Polynitrophenols
• Cyclonite
2,4,6-Trinitrotoluene
• Toluene
Xylene
The CAV-OX* process can treat the following contaminants in
groundwater:
Bis(2-chloroethyl)ether
Creosote
1,2-Dichloroethane
• Dichloroethene
Dioxins
• Dioxanes
Freon 113
• MEK
MIBK
• Methylene chloride
• PCBs
• PCP
• Pesticides
• PAHs
• Tetrachloroethene
• 1,1,1-Trichloroethane
• Trichloroethene
Tetrahydrofuran
• Vinyl chloride
• Triglycol dichloride ether
The cavitation process alone reduces contaminant
concentrations by about 20 to 50 percent. The synergistic
combination of cavitation and UV radiation can reduce
contaminant concentrations from 95 to 99.99 percent.
Treatment By-Products
The CAV-OX* process produces no air emissions and
generates no residue, sludge, or spent media that require further
processing, handling, or disposal. If contaminants are reduced
to nondetectable levels, the effluent consists of water with some
dissolved carbon dioxide gas, halides (for example, chloride),
and in some cases organic acids. No VOCs are released to the
atmosphere. Any remaining contaminants remain in the effluent.
The CAV-OX* process can break down single- and multiple-
bond organic compounds, aliphatics, aromatics, heterocyclics,
and related chemicals. Pure benzene, for example, is transformed
into carbon dioxide and water, while the breakdown of
trichloroethane would probably result in residual chlorides.
The CAV-OX* process does not treat metals. It may,
however, oxidize metallic ions or reduce metallic salts in the
process of destroying organic contaminants.
Operating Modes
The CAV-OX* process can be operated in one of three
modes:
Cavitation chamber only
• Cavitation chamber with low-energy U V radiation and
hydrogen peroxide
• Cavitation chamber with high-energy UV radiation and
hydrogen peroxide
31
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Applications
The CAV-OX* process has the following applications:
• Treatment of groundwater, wastewater, industrial
process water, and drinking water, or generation of
ultrapure water, either as a stand-alone process or as
part of a treatment train
• Pretreatment of industrial effluent prior to discharge to
a publicly owned treatment works
• Final polishing prior to reuse or discharge to a receiving
water body
Treatment Capacity
Theoretically, a CAV-OX® process of any given size can be
constructed and operated. The design is modular; for example,
groups of 250-gpm units can be operated together in parallel.
The smallest CAV-OX* unit operated to date is a 1-gpm
unit. This unit was built for a distributor to carry in the trunk
of his car to demonstrate to customers. Several mid-size units
(10- to 20-gpm capacity) are operational. A 50-gpm unit has
been built and delivered to a major soft drink company.
Pretreatment Requirements
In general, advanced oxidation systems require influent
characteristics that may necessitate some pretreatment. Table
A-l lists desirable influent characteristics for the CAV-OX®
process.
The cavitation chamber is not affected by the quality of the
influent or the type of contaminants. The specifications provided
above are intended to limit suspended solids, which absorb UV
energy and decrease effective UV energy.
Typically, the only pretreatment equipment required for
the CAV-OX* process is a holding tank to ensure a constant
stream flow to the process. In cases of high turbidity or other
interfering agents, filtration equipment may also be required.
Transportation to Site
A CAV-OX* process is very compact and easily transported
to the installation site. A skid-mounted 10-gpm CAV-OX* unit
measures 5-foot by 4-foot by 7-foot and weighs about 600
pounds.
Table A-1. Desirable Influent Characteristics
Characteristic
Turbidity
Iron salts
Color
Suspended matter
Free product
Value
< 25 NTU
< 5 mg/L
< 25 TCU
< 1 0 microns
< 25 mg/L
Installation
A CAV-OX* unit is very easy to install and generally has a
small footprint relative to the process flow rate. For example, a
20-gpm unit needs a 6-foot by 6-foot area and has a shipping
weight of about 800 pounds. Each process is skid-mounted and
transportable, and requires only the connection of 1-inch unions
to complete the process flow. Construction materials are stainless
steel and quartz glass with Viton™ rubber seals.
Power Requirements
The CAV-OX* I low-energy process requires a 230-volt, 3-
phase, 30-ampere power supply. An internal transformer
supplies 120-volt, single-phase, 10-ampere power for the
chemical feed pump and control panel.
The CAV-OX® II high-energy process requires a 480-volt,
single-phase, 30 ampere power supply, and a separate 120-
volt, single-phase, 10-ampere power supply for the chemical
feed pump and control panel.
Installation Time
A CAV-OX* unit can be placed on an existing concrete pad,
wired to an existing disconnect box, and made operational in
about 4 hours.
Permanent Installation
Permanent installation requires a concrete pad, security fence,
open air metal roof, electric power, and inlet and outlet fluid
lines. Additional requirements include a holding tank (about
250 to 500 gallons), located above the centrifugal pump inlet
line to ensure adequate head, and a hydrogen peroxide
subassembly. If a carbon polishing unit is used for post
treatment, additional space for the carbon canisters must be
provided. The CAV-OX® unit should be oriented so that
hydrogen peroxide tanks can be easily exchanged as needed.
32
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Portable Units
A CAV-OX* process is easily moved and can be mounted
on either a truck bed or a trailer. One consulting firm has
moved its 10-gpm CAV-OX® process to three different customer
locations, obtaining rental fees many times the initial cost of
the unit.
Hydrogen Peroxide Supply
A chemical pump for hydrogen peroxide is installed
downstream of the cavitation chamber and before the UV
reactors. The pump can be either hard wired to the control
panel or operated with a utility power cord plugged into the
120-volt outlet on the side of the control panel. A circuit breaker
inside the control panel provides a safety disconnect for the
hydrogen peroxide supply.
The chemical pump is usually placed on top of the hydrogen
peroxide tank so that the suction line is as short as possible for
best pump performance.
As an alternative, hydrogen peroxide can be mixed with
the influent in the holding tank. Suitable mixing and control
methods must be provided.
Personnel Requirements
Training to operate the CAV-OX* equipment can be
completed in about 8 hours. Personnel may also need the OSHA
40-hour health and safety training. Magnum recommends an
additional 8 hours of "hands-on" operation tc enable any
personnel to become proficient with the equipment.
The CAV-OX* process requires little attention during
operation and can be operated and monitored remotely, if
needed. Remotely monitored systems can be connected to
devices that automatically dial a telephone to notify responsible
parties at remote locations of divergent operating conditions in
the CAV-OX* equipment. Remotely operated and monitored
systems are hard-wired into centrally located control panels or
computers through programmable logic controllers.
Comparison with Other Advanced Oxidation
Technologies
The CAV-OX® process generates hydroxyl radicals at almost
no cost. By comparison, ozone is not only expensive and
hazardous, but must be added using a method that ensures no
ozone is released to the atmosphere.
Other systems use multiple medium-energy UV lamps to
photolyze hydrogen peroxide. Generally, UV tubes exposed to
contaminants with this methodology become scaled, reducing
UV transmission. To avoid this problem, a complicated wiper
process is provided to clean the scale from the tubes. This, in
turn, requires careful maintenance to monitor the output
efficiency of the overall process.
The CAV-OX* process is free from such scaling problems.
It generates hydroxyl radicals primarily from the cavitation
process and secondarily from photolyzation of hydrogen
peroxide. The hydroxyl radicals resulting from the cavitation
process react with the dissolved gases, and the associated
hysteresis effect reduces, if not eliminates, the scaling effect
common to most UV systems. Furthermore, the gases and
residual microbubbles dissolved in the fluid lower its density,
thereby enhancing the ability of the process to oxidize organic
contaminants. This effect also increases the synergistic effect
between cavitated flow and UV radiation, improving the
efficiency of the process.
Technical Data and Cost Comparisons
This section presents technical data collected by Magnum
at Edwards Air Force Base (Edwards) independently of the
Superfund Innovative Technology Evaluation (SITE)
demonstration of the CAV-OX® process. This includes data for
the use of cavitation alone, and economic comparisons with
conventional groundwater treatment systems and carbon
adsorption systems.
Figure A-l is a photograph of the CAV-OX* process used
at Edwards.
SITE Demonstration Results
During the SITE demonstration at Edwards, Magnum
collected additional samples following Magnum's sampling
matrix and sampling protocols. These additional samples were
independent of samples collected for the SITE Program
evaluation of the CAV-OX® technology. The results of these
additional samples were not considered when developing
conclusions for the SITE Program evaluation. Fifty- four samples
were collected and analyzed on site in a mobile laboratory. The
samples were analyzed using a Shimadzu GC-14A gas
chromatograph and a modified EPA Method 8021. Results were
available in 2 to 4 hours. Tables A-2 through A-7 present data
from Magnum collected during the demonstration.
Cavitation Chamber Only
In a limited number of situations, a CAV-OX® cavitation
chamber and ancillary equipment can be used as a stand-alone
process to reduce contaminant concentrations by 50 to 80 percent.
This operating mode is the least expensive; however, it normally
is not effective for contaminants requiring high percentage
reductions.
33
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Figure A-1. CAV-OX • Process Used at Edwards Air Force Base
34
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Table A-2. Mobile Laboratory Results for Samples Collected 3/24/93 (^lg/L)
Sample Description Source Benzene TCE Toluene Ethyttxnzene Xylenes Hydrogen
Peroxide
POL NA 1 0.40 1 1 3 NA
Influent Process 226 2,010 35.63 3.5 86.47
influent
0.36WV/1.5gpm High-energy 210 1,360 28.2 4.07 66.1
Omg/LH2O2 process
effluent
10kW/1.5gpm High-energy 87 15.4 6.63 1.15 8.84
Omg/L H2O2 process
effluent
Notes: PQL = Practical quantitation limit
NA = Not Applicable
Table A-3. Mobile Laboratory Results for Samples Collected 3/24/93 (fjg/L)
Sample Description Benzene TCE Toluene Ethylbenzene Xylenes Hydrogen
(total) Peroxide
PQL 1 0.40 1 1 3 NA
Influent 88.4 1,180 1.90 ND ND'
,
0 holding time
Notes: ' = Sample diluted to a ratio of 1:10. PQLs for ND compounds should be raised 1:10 to account for dilution.
NA - Not Applicable
35
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Table A-4. Mobile Laboratory Results for Samples
Sample Description
PQL
Influent
0 kW/1.5 gpm/0 mg/L H2O2
0 holding time
0 kW/1 gpm/0 mg/L H2O2
20 mm. holding time
0 kW/1 gpm/0 mg/L H2O2
45 mm. holding time
0 kW/1 gpmV mgA. H202
0 holding time
Verification of Process Influent
Influent from bladder tank
Influent from holding tank
Notes: PQL = Practical quantitation limit
NA = Not applicable
ND = Not detected
Table A-S. Mobile Laboratory Results for Samples
Collected 3/24/93 fag/L)
Benzene
1
150
167
197
89.4
211
177
202
TCE
0.40
993
1,130
1,350
668
1,340
1,010
1,140
Toluene Ethylbenzene
1 1
4.30 ND
8.06 2.98
9.13 3.25
1.93 ND
7.24 1.00
6.36 ND
7.12 ND
Xylenes
(total)
3
ND
5.98
6.47
ND
3.00
ND
ND
Hydrogen
Peroxide
NA
0
0
0
0
30.00
NA
NA
Collected 3/24/93 (fjg/L)
Sample Description Benzene
PQL
Influent
0 kW/1 gpm/0 mgA. H2O2
0 holding time
0 kW/1 gpm/0 mgA. H2O2
0 holding time
2.5 kW/1 gpm/0 mg/L H2O2
0 holding time
5.0 kW/1 gpm/0 mg/L H2O2
0 holding time
2.5 kW/4 gpm/0 mg/L H2O2
0 holding time
10.0 kW/4 gpm/0 mg/LH2O2
0 holding time
Influent/350 mg/L H2O2
Influent/350 mg/L H2O2
5.0 kW/4.0 gpm/350 mg/L H2O2
0 holding time
1
336
254
281
73.2
14.8
30.9
26.7
320
316
1.03
TCE
0.4
1,684
1,240
1,380
275
50.3
340
266
7636
1650
30.7
Toluene Ethylbenzene
1 1
44.2 6.99
32.7 4.94
35.5 5.28
ND 1.19
1.24 ND
3.08 ND
2.35 ND
41.3 6.32
40 8 6.56
ND ND
Xylenes
(total)
3
29
21.6
22.4
ND
ND
ND
ND
26.7
27
ND
Hydrogen
Peroxide
NA
0
0
0
0
0
0
350
350
350
350
Notes: PQL = Practical quantitation limit
NA = Not applicable
ND = Not detected
36
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Table A-6. Mobile Laboratory Results for Samples Collected 3/25/93
Sample Description
PQL
0 kW/1 gpm/0 mg/L H2O2
24 hour holding time
Influent
0 kW/1 gpm/0 mg/L H2O2
0 holding time
0 kW/10 gpm/0 mg/L H2O2
0 holding time
0 kW/1 gpm/0 mg/L H2O2
0 holding time/1 hour recycle
through chamber
0 kW/1 gpm/0 mg/L H2O2
1 hour holding time
Influent with 90 mg/L H2O2
0 holding time
0 kW/1 gpm/90 mg/L H2O2
0 holding time
0 kW/1 gpm/90 mg/L H2O2
1 hour holding time
2.5 kW/5 gpm/90 mg/L H2O2
0 holding time
10.0 kW/2 gpm/90 mg/L H2O2
0 holding time
5.0 kW/5 gpm/90 mg/L H2O2
0 holding time
2.5 kW/0.5 gpm/90 mg/L H2O2
0 holding time
10.0 kW/8+ gpm/90 mg/L H2O2
0 holding time
0 kW/0.25 gpm/0 mg/L H2O2
30 mm. holding time
Benzene
1
229
388
314
321
298
229
381
247
305
114
ND
31.3
ND
3.89
165
TCE
0.40
986
1,860
1,510
1,450
1,410
1,030
1,850
1,110
1,430
673
11
311
14
66.30
658
Toluene
1
25.1
55
40.7
40.6
38.2
27.8
55.2
30.8
42.5
76.9
ND
3.12
ND
ND
34.5
Ethylbenzene
1
8.37
6.79
3.22
2.69
3.09
1.94
7.15
2.19
5.65
3.73
ND
ND
ND
ND
6.05
Xylenes
(total)
3
ND
24
15.6
14
14.8
9.94
24.9
6.93
19.3
8.82
ND
ND
ND
ND
27.3
Hydrogen
Peroxide
NA
0
0
0
0
0
0
90
90
90
90
90
90
90
90
0
Notes: PQL = Practical quantitation limit
NA = Not applicable
ND = Not detected
37
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Table A-7. Mobile Laboratory Results for Samples Collected 3/26/93 (fjg/L)
Sample Description
PQL
0 kW/1 gpm/0 mg/L H2O2/0
0 holding time/1 hour recycle
through cavitation chamber
Influent
0 kW/0.15 gpm/0 mg/L H2O2
0 holding time
10 kW/2 gpm/0 mg/L H2O2
0 holding time
5.0 kW/4 gpm/120 mg/L H2O2
0 holding time
10 kW/4 gpm/120 mg/LH2O2
0 holding time
10 kW/8 gpm/90 mg/L HJ3,
0 holding time/pH 5.5
0 kW/2.5 gpm/90 mg/L H2O2
0 holding time
0 kW/1 gpm/0 mgA. H£>2
10 mm. holding time/pH 5.0
0 kW/2 gpm/0 mg/L H2O2
10 min. holding time/pH 5.0
Influent - pH 5.0
0.36 kW/1.5 gpm/90 mg/LH2O2
0 holding time
Influent - normal pH - 90 mg/L H2O2
0 holding time
10 kW/4.0 gpm/90 mg/L H2O2
0 holding time
Benzene
1
154
381
357
81.5
26.4
14.9
4.19
29.01
265
267
423
31.3
418
16.2
TCE
0.40
668
1,350
1,280
34.6
179
113
52.6
70.6
1,010
1,020
1,620
320
1,610
126
Toluene
1
21.3
109
104
12.5
5.25
283
ND
6.02
67.7
69.4
110
5.51
102
2.4
Ethylbenzene
1
4.22
8.78
10.9
1.19
ND
ND
ND
ND
3
3.02
5.37
ND
3.43
ND
Xylenes
(total)
3
14.2
68.1
63.8
3.3
ND
ND
ND
ND
35.6
36.3
57.5
ND
44.3
ND
Hydrogen
Peroxide
NA
0
0
0
0
120
120
90
90
0
0
0
90
90
90
Notes: PQL = Practical quantitation limit
NA = Not applicable
ND = Not detected
38
-------
Case Study C-8 in Appendix C provides an example of
using the CAV-OX® cavitation chamber only. In this case study,
a CAV-OX® process capable of processing 3,900 gallons per
hour was designed for Southern California Edison Company to
treat 3 million gallons of contaminated seawater with a high
biochemical oxygen demand (BOD). This section discusses
procedures and results for using the cavitation chamber only,
without UV radiation or hydrogen peroxide.
Procedure
The influent to the CAV-OX* process is drawn from a
holding tank. A positive head from the holding tank is necessary
for the centrifugal pump inlet.
The centrifugal pump releases fluid at about 70 pounds per
square inch (psi). This 70-psi fluid flows directly into the
cavitation chamber, where the pressure is made to drop suddenly
to near vacuum. The sudden drop in pressure causes the aqueous
molecules to dissociate, forming hydrogen atoms and hydroxyl
radicals. Any organic contaminants in the fluid are likewise
forced to undergo a sudden pressure drop, breaking weak bonds.
These contaminants are also attacked by the atomic hydrogen
and hydroxyl radicals from the dissociation of the fluid.
In certain applications, compounds in the fluid leaving the
cavitation chamber not have time to react completely. In these
cases, a dwell tank is used so that the fluid reaction can continue
for as long as 15 minutes.
Results
Table A-8 presents selected results from the SITE
demonstration for use of the cavitation chamber only.
Economic Analysis
Typical operating costs (presented in October 1993 dollars)
for the CAV-OX® process are as follows:
CAV-OX* cavitation chamber only — about $0.50 per
1,000 gallons of treated water
CAV-OX* cavitation chamber with low-energy UV
radiation and hydrogen peroxide — about $2 pee 1,000
gallons of treated water
CAV-OX* cavitation chamber with high-energy UV
radiation and hydrogen peroxide — about $4 per 1,000
gallons of treated water
Table A-9 presents cost data for three groundwater treatment
methods: a filter carbon process, an air carbon process, and
UV radiation plus hydrogen peroxide. The contaminant of
concern was benzene, and the treatment goal was to reduce its
concentration from 50,000 micrograms per liter (ug/L) to 50
ug/L. The results of this comparison were as follows: the
filter carbon process cost $ 11.07 per 1,000 gallons; the air carbon
process cost $14.07 per 1,000 gallons; and UV radiation plus
hydrogen peroxide cost $8.22 per 1,000 gallons.
Table A-10 presents cost data for a 10-gpm CAV-OX* I
low-energy process and a conventional carbon adsorption process
to treat two sites contaminated with BTEX, trichloroethene
(TCE), tetrachloroethene (PCE), and chloroform. The annual
cost of operating the carbon adsorption process was $22,648
for the first site and $13,855 for the second site, while the
annual cost of operating the CAV-OX® process was $ 10,964 for
the first site and $7,468 for the second site.
References
Flint, E. B. and Suslick, K. S. 1991. "The Temperature of
Cavitation." Science. Volume 253. September 20.
Suslick, K. S. 1989. "The Chemical Effects of Ultrasound."
Scientific American. February.
Suslick, K. 1990. "Sonochemistry." Science. Volume 247.
March 23.
39
-------
FaWe A-8. Developer-Generated SITE Demonstration Results, (Percent Reduction), CAV-OX* Captation Chamber Only
Sample Description
Date Benzene Ethylbenzene Toluene Xytene TCE TCE
(%) W (%) (%) (ug/L) (%)
Protocol A
ND
*
OkW/1gprrMmgfl.H202
1 hour holding time
24 hour ho/ding time
3
,
Protocol B
37
38
38
1-62° 38
m. holding time/pH 5
3
OkW/1gpm/Omg^H202
45 mm. holding time
Protocol C
OkW/lgpmMmg/L H20
0 holding time/1 hour cavitation chamber
Q3/25/93 23
54
31
38 1,860
24
OkW/IOgpmVmgA. H2O2
0 holding time
Q3/25/g3 17
60
26
42 1,860
22
OkW/1gpm/OmgA.H202
0 holding time
03K5S93 19
53
26
35
1,860 19
OkW/1gPm/Omg/LH202
10 mm. holding time
18
Notes: Neither hydrogen peroxide nor UV radiation was
used in these tests.
ND = Not detected
40
-------
Table A-9. Economic Comparisons for Groundwater Treatment Process ($) **
Item
Equipment
Installation
Total
Filter Carbon Air Carbon
150,000
20,000
170.000
Capital Cost
195,000
30,000
225,000
UV/Hydrogen
Peroxide
115,000
20,000
135,000
CAV-OX"!
Low-Energy
Process
58,000
3,000
61,000
Annual Operating Costs
Power ($0.08/kWh)
Carbon
Chemicals
Maintenance
Amortization (20% per year)
Labor (air monitoring)
Total
Cost per 1,000 gallons
0
108,000
0
7,500
30,000
0
145,500
11.07
Notes: ' All treatment processes had a
11,700
108,000
0
11,250
45,000
9,000
184,950
14.07
flow rate of 25 gpm
62,200
0
12, 100
6,750
27,000
0
108,050
8.22
and were used to treat 50
3,592
0
1,741
5,114
11,600
0
22,047
1.67
mg/L
benzene in groundwater to 50 ug/L.
Cost data provided by Magnum
Table A-10. Economic Comparison Between a Carbon Adsorption System and CAV-OX® I Low-Energy Process ($) '
Site
Cost Per 1,000 Gallons Annual Cost
Carbon Adsorption System
4.3"
22,648
2.64C
13,855
CAV-COPI Low-Energy Process"
2.08
10,964
Notes:
1.46
7,468
TWs analysis assumes a flow rate of 10 gpm and the following contaminant concentrations (in ug/L):
Site 1: benzene, 350; toluene, 340; ethylbenzene, 34; xylenes, 270; TCE, 33; PCE, 33; and chloroform, 10
Site 2: benzene, 2; toluene, 2; ethylbenzene, 40; xylenes, 82; TCE, 33; PCE, 10; and chloroform, 5
Assumes 42.5 pounds of carbon per day at $1.46 per pound
Assumes 26 pounds of carbon per day at $1.46 per pound
Includes all operating costs amortized over a 5-year period
41
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Appendix B
SITE Demonstration Results
In February 1992, Magnum Water Technology (Magnum)
responded to the U.S. Environmental Protection Agency's (EPA)
annual solicitation for proposals to participate in the Superfund
Innovative Technology Evaluation (SITE) Program. At that time,
Magnum discussed the possibility of demonstrating the
CAV-OX* process's treatment of contaminated groundwater at
Edwards Air Force Base (Edwards) under the SITE Program.
EPA subsequently accepted the CAV-OX* process into the SITE
Program. Through a cooperative effort among the EPA Office
of Research and Development (ORD), EPA Region 9, State of
California Department of Toxic Substance Control, State of
California Regional Water Quality Control Board, and Edwards,
the CAV-OX® process was demonstrated at Edwards Site 16
under the SITE Program. This appendix briefly describes
Edwards Site 16 and summarizes the SITE demonstration
activities and demonstration results.
Site Description
Edwards is a 300,000-acre U.S. Air Force base about 75
miles northeast of Los Angeles, California. The base is located
on and adjacent to Rogers Dry Lake, a basin of internal drainage
(Figure B-l) (Engineering-Science, 1988). Operations at the
base began in the 1940s. Primary physical structures throughout
the base include runways, buildings, and hangars housing aircraft,
support equipment, and personnel.
The CAV-OX* process was demonstrated at Site 16, a
military-grade jet fuel (JP-4) spill site located between Wolfe
Avenue, Taxiway D, and Buildings 1810 and 1820 (Figure B-2).
Site 16 occupies about 12 acres in an area that includes taxiways,
hangars, office buildings, outside storage, and open fields. Other
features at Site 16 include parking areas, a security station,
equipment and supply storage yards, and sewer lines.
A shallow aquifer underlies Site 16. This aquifer is generally
encountered between 8 and 20 feet below ground surface and
occurs mainly in weathered granite, with some areas occurring
in the overlying alluvium (Engineering-Science 1988).
Groundwater flow in the shallow aquifer is to the east-northeast
with a hydraulic gradient of less than 1.5 x 10'2.
The JP-4 release was originally attributed to a leaking fuel transfer
line that runs along the western boundary of Site 16. The leak
began about September 1983 and contaminated about 12 acres.
A measurable floating layer of fuel currently covers about 7 acres.
The total quantity of free-floating fuel is estimated to be between
250,000 and 300,000 gallons (Engineering-Science 1988).
The State of California Regional Water Quality Control
Board, Lahontan Region issued a Clean-Up and Abatement Order
(No. 84-10) for Site 16 on November 13, 1984. This order was
followed by remedial actions including pipeline replacement and
monitoring well installation. Further investigation included a
feasibility study and remedial design for cleanup of the fuel spill.
The remedial action combined a recovery well process, a
recovery fuel storage process, and a fuel-water separator process.
Discharge water from the process was routed to the base sanitary
sewer process, and the fuel was collected for reuse. However,
dissolved trichloroethene (TCE) was later detected in the water
above discharge limits. Because TCE could not be discharged
to the sanitary sewer process, the recovery well process ceased
operation in December 1987 (Engineering-Science 1988).
Contaminated groundwater for the demonstration was
obtained from Site 16. The contaminated groundwater contains
volatile organic compounds (VOC), primarily TCE, benzene,
toluene, ethylbenzene, and xylene (BTEX); and low levels of
carbon tetrachloride; chloroform; 1,1-dichloroethane; 1,2-
dichloroethane; 1,1-dichloroethene; trans- 1,2-dichloroethene;
tetrachloroethene (PCE); 1,1,1-trichloroethane; and 1,1,2-
trichloroethane.
A site assessment was completed in June 1989 through the
Department of Defense Installation Restoration Program. A pilot
plant study was completed for the site in May 1990. This study
proposed a treatment process that included an ultraviolet-
oxidation unit and air stripping to treat contaminated groundwater
from recovery wells at Site 16.
43
-------
3
55
o
3
UI 03
44
-------
LEGEND
• Monitoring Well Location and Designation
Underground JP-4 Fuel Line
Approximate Location of Floating Fuel Layer
Source: Engineering-Science 1988
Figure B-2. Site 16 Layout
1" - 350'
APPROXIMATE SCALE
45
-------
Site Contamination Characteristics
On-Site Support Services
In October and November 1991, Edwards sampled
monitoring wells at Site 16 and analyzed the samples for VOCs,
semivolatile organic compounds (SVOC), metals, and a variety
of other parameters including pH and alkalinity.
VOCs present in high concentrations included TCE
(nondetectable [ND] to 3,100 micrograms per liter [ug/L]),
benzene (ND to 1,800 ng/L), toluene (ND to 3,100 ug/L),
ethylbenzene (ND to 1,300 ug/L), and p- and m-xylene (ND to
3,300 ug/L). Other contaminants with concentrations above
detection limits were l,l-dichloroethane(NDto 154 ug/L); 1,2-
dichloroethane (ND to 7 ug/L); trans-1,2-dichloroethene (ND
to 1.7 ug/L); PCE (ND to 3.3 ug/L); 1,1,1-trichloroethane (ND
to 270 ug/L); and dichloromethane (ND to 230 ug/L). Other
sampling parameters included pH of 7.4 and alkalinity (as
calcium carbonate) at 450 milligrams per liter (mg/L).
Review of SITE Demonstration
Three configurations of the CAV-OX* process were
demonstrated: the CAV-OX® I low-energy process operating at
360 watts and the CAV-OX* II high-energy process operating
at either 5 kilowatts (kW) or 10 kW. The CAV-OX* I process
contains six 60-watt lamps per reactor. The CAV-OX* II process
contains two ultraviolet (UV) reactors with one UV lamp each;
it can operate at 2.5, 5,7.5, or 10 kW. Flow capacity is estimated
to be less than 3 gallons per minute (gpm) for the CAV-OX* I
process and less than 5 gpm for the CAV-OX® II process as
demonstrated. Groundwater from monitoring wells 16-4, 16-
17, and 16-49 was used for the demonstration. The demonstration
consisted of 15 planned runs for each configuration of the
CAV-OX* process over a 4-week period. The following sections
describe the demonstration and review the CAV-OX* process's
performance during the demonstration.
Site Preparation
A 2,000 square-foot area was used for both CAV-OX*
configurations, support facilities, nonhazardous and hazardous
waste storage containers, and the office and field laboratory
trailer. Site preparation included setting up major support
equipment, on-site support services, and utilities. A schematic
of the process is shown in Figure B-3.
Major Support Equipment
Support equipment for the CAV-OX® process demonstration
included storage tanks for untreated and treated groundwater, a
solid waste dumpster for disposal of nonhazardous wastes, 55-
gallon drums for storage of decontamination rinse water, a forklift
for unloading and loading support equipment, three submersible
positive displacement pumps with gasoline-powered generators,
sampling and analytical equipment, and health and safety
equipment.
A10-foot by 40-foot air-conditioned office trailer containing
furniture and filing cabinets was used to complete and file daily
oversight and data collection reports, house laboratory equipment
for field analyses, and store small equipment and supplies.
Rooms within the trailer were used to separate administrative
and laboratory activities. Edwards provided access to restrooms
in Building 1820 for use by demonstration personnel.
Utilities
Utilities required for the demonstration included water,
electricity, and telephone service. Water was required for
equipment and personnel decontamination. Edwards provided
about 20 to 50 gallons per day of potable water for
decontamination. Drinking water was available inside the office
and laboratory trailer in 1-gallon containers.
Operation of the CAV-OX® process requires electricity. At
Edwards, the CAV-OX* I process used a 220-volt, 3-phase, 30-
ampere electrical service. The CAV-OX* II process used a 480-
volt, single-phase, 20-ampere electrical service. Additional 110-
volt, single-phase, 10-ampere electrical service was needed for
UV power supply controls and chemical feed pumps. The office
and laboratory trailer required 220-volt, 3-phase, 50-ampere
electrical service.
Two cellular telephones in the office and laboratory trailer
were used for ordering equipment, parts, reagents, and other
chemical supplies, and for scheduling deliveries.
Technology Demonstration
This section discusses (1) operational and equipment
problems, (2) health and safety considerations, and (3) site
demobilization associated with the SITE demonstration.
Operational and Equipment Problems
Hydrogen peroxide is usually injected in-line with a small
chemical feed pump; however, for the demonstration it was added
directly to the influent holding tank. In normal field operations,
treatability studies would be conducted to determine preferred
operating conditions; the CAV-OX* process would then be
adjusted until preferred conditions were achieved. Because the
chemical feed pump is highly influenced by the pressure of the
CAV-OX® process, optimization of the process often requires
numerous chemical feed pump adjustments, with hydrogen
peroxide analyses following each adjustment. Usually, this
optimization process would be done only one time for the desired
flow rate at the preferred hydrogen peroxide injection level.
However, during the demonstration three hydrogen peroxide
concentrations were examined at three flow rates, and operating
conditions changed several times each day. Therefore, adding
hydrogen peroxide in-line would have required continuous
46
-------
Groundwatar from
Site 16 Monitoring Wells
Recycle
-^^Hra§~
Cavttatfon Chamber
High-Energy
UV Reactor
To Effluent
' Storage Tank
SAMPLE COLLECTION (S) OR
MEASUREMENT (M) LOCATION
MAIN FEED LINE FROM
INFLUENT HOLDING TANK
EFFLUENT LINE FROM
CAV-OX • I UV REACTOR
EFFLUENT LINE FROM
CAV-OX • II UV REACTOR
LOCATION
IDENTIFIER
S1
M1
S2
M2
S3
M3
PARAMETERS
SAMPLE
TCE. BTEX.
HYDROGEN PEROXIDE, TOC,
TC, POC, METALS, ALKALINITY,
HARDNESS, TRPH, VOCS (GC/MS),
SVOC. TURBIDITY, BIOASSAY
MEASUREMENT
pH, TEMPERATURE,
FLOW RATE.
SPECIFIC CONDUCTANCE
S ) - Sample Location
- Measurement Location
Figure B-3. CAV-OX* Process Sample and Measurement Locations
47
-------
adjustment of the chemical feed injection rate. Because of the
time required with in-line adjustment, hydrogen peroxide was
added directly to the influent holding tank until the desired
concentration was reached.
Health and Safety Considerations
In general, potential health hazards resulted from possible
exposure to contaminated groundwater and hydrogen peroxide
solution. Although the treatment process was entirely closed,
potential routes of exposure during the demonstration included
inhalation, ingestion, and skin and eye contact from splashes
or spills during sample collection.
All personnel working in the demonstration area had, at a
minimum, 40 hours of health and safety training and were under
routine medical surveillance, in compliance with federal OSHA
regulation 29 CFR 1910.120. Appropriate personal protective
equipment (PPE) was used for each activity being performed.
Steel-toe boots were required in the exclusion zone. Personnel
working in direct contact with contaminated groundwater and
process chemicals wore modified Level D protective equipment,
including safety shoes, latex inner gloves, nitrile outer gloves,
and safety glasses.
Site Demobilization
After the demonstration was completed and on-site
equipment was disassembled and decontaminated, equipment
and site demobilization began. Equipment demobilization
included loading the support equipment, transporting it off site,
returning rented support equipment, and disconnecting utilities.
The CAV-OX® configurations remained mounted on a flat-bed
truck so that they could be transported off site after the influent
line, effluent line, and electricity were disconnected.
Decontamination was necessary for the bladder tank,
effluent storage tank, sampling equipment, pumps, mixers,
valves, and nondisposable PPE. Magnum was responsible for
decontaminating the CAV-OX® equipment and its health and
safety equipment.
The effluent was disposed of off site, in accordance with
Edwards base regulations. Total liquid wastes were about 8,500
gallons. The demonstration evaluated runs with numerous
operating conditions, not all of which resulted in an effluent
that met discharge limits; also, untreated groundwater was used
for daily calibrations of flow meters with the UV reactor off.
Therefore, the discharge water collected during the
demonstration did not meet State of California drinking water
action levels and federal drinking water maximum contaminant
levels (MCL) for TCE and BTEX. The collected water could
not be discharged to the sanitary sewer and was disposed of off
site in accordance with arrangements made among EPA,
Edwards, EPA Region 9, and the State of California.
Other liquid and solid wastes generated during the
demonstration included (1) washwater from decontaminating
personnel and equipment; (2) disposable PPE, such as Tyvek*
suits, gloves, and boot covers; and (3) disposable laboratory
supplies, such as spent vials, empty reagent containers, and paper
towels. Solid wastes were collected in plastic bags, 55-gallon
drums, and dumpsters. All liquid and solid wastes were disposed
of in accordance with disposal arrangements made among EPA,
Edwards, EPA Region 9, and the State of California.
Experimental Design
The demonstration's objectives were to: (1) determine TCE
and BTEX removal efficiencies in the treatment process under
various operating conditions, (2) determine whether TCE and
BTEX levels in treated groundwater met applicable discharge
limits to the base sanitary sewer at the 95 percent confidence
level, and (3) compare TCE and BTEX removal efficiencies
among the three treatment process configurations. Secondary
objectives for the technology demonstration were to (1) collect
information, including process chemical dosage and utility
requirements, needed to estimate treatment costs, (2) assess the
presence of degradation by-products in the treated water, and
(3) collect characterization data for both the influent and effluent
streams. The sections that follow describe the testing approach
and sampling and analytical procedures used to accomplish these
objectives.
Testing Approach
Water from monitoring wells 16-4, 16-17, and 16-49 was
pumped through a common manifold into a 7,500-gallon
equalization (bladder) tank. The combined flow from the three
wells was about 4 gpm. An equalization tank was used to
minimize any variability in the influent characteristics (primarily
VOCs), and to provide a steady water supply to the CAV-OX®
process. The bladder tank was made of heavy duty,
polyurethane-coated nylon fabric and was rated for potable water.
Before the demonstration began, approximately 7,500 gallons
of water were collected in the equalization tank. Water was
collected simultaneously from the wells to obtain a representative
mix of the contaminant plume. To minimize volatilization of
VOCs, water in the equalization tank was not mixed by any
other means. A separate pump transferred water from the
equalization tank to an influent holding tank, mounted on
Magnum's truck.
Operations followed the schedule shown in Table B-1. The
CAV-OX* I low-energy process was operated simultaneously
with the CAV-OX® II high-energy process. The CAV-OX* II
high-energy process operated with the UV reactor at 5 kW and
then at 10 kW. From the equalization tank, the water was
transferred to an influent holding tank, where hydrogen peroxide
was added. The influent holding tank maintained a positive head
for the centrifugal pump. The water was then pumped through
48
-------
Table B-1. Experimental Conditions
Rfi
Hydrogen
Influent pH Peroxide (mg/L)
Process Flow Rate (gpm)
CAV-OX*!
54
-------
the cavitation chamber. After exiting the cavitation chamber,
the water flowed to either the UV reactors, or back to the
cavitation chamber through a recycle line. The water flowing
to the UV reactors was split between the CAV-OX* I and the
CAV-OX® II reactors. Treated groundwater was stored in an
effluent storage tank for off-site disposal.
The CAV-OX® I process was operated unchanged while
the CAV-OX* II process was operated first at 5 kW and then at
10 kW. Sampling of all three CAV-OX* configurations was
completed for one run before the next run began.
Operating parameters, including hydrogen peroxide dose,
hydraulic retention time (flow rate), and UV output were varied
to observe how the process performed under different operating
conditions. The initial flow rate was based on known
groundwater contaminant concentrations and Magnum's
professional judgment and experience. Preferred operating
conditions were then determined by Magnum as those that
reduced effluent VOCs to below target levels. Table B-2 shows
VOC target levels for the demonstration.
Table B-2. Target Levels for Critical Analytes in Effluent Samples
Contaminant
TrichtocelheneCrCQ
BenzBDB
Toluene
Bhyhenzene
Total Xyiene
Concentration
(U9V
5
1
20
680
1,750
The first test run was preceded by a preliminary run.
Operating parameters for the preliminary run were identical to
those of the first test run, including the use of contaminated
groundwater. The purpose of the preliminary run was to identify
and resolve any problems in the sampling and field analysis
protocols and to remove any residual contaminants from previous
use. Only field analyses (such as temperature and flow rate)
were performed during the preliminary run. Steady state
conditions (a stable flow rate) were achieved for the preliminary
run after approximately three hydraulic retention times.
Sampling and Analytical Procedures
Figure B-3 shows the three locations where samples were
collected and measurements taken during the demonstration.
Treated water was sampled and measured only after steady
state was attained (after three hydraulic retention times).
Before each run, hydrogen peroxide in the influent was
measured to determine concentrations. In addition, the influent
flow rate was adjusted before each run to provide the desired
hydraulic retention time.
VOC concentrations and flow rate were considered critical
parameters for evaluating the technology. VOCs were measured
by both gas chromatography (GC) and GC/mass spectrometry
(MS) methods. Only GC measurement of VOCs was considered
critical because GC data were planned for quantitative use;
GC/MS data were planned for qualitative use providing data on
degradation products or other contaminants.
Because the CAV-OX* process was developed to treat
organics, and because VOCs were the principal contaminants
in groundwater, four replicate samples were collected for GC
analysis of VOCs to increase accuracy and precision. For other
analytes, the number of samples was based on the (1) intended
use of the data, (2) analytical costs, (3) sampling time, and (4)
analytical laboratory discretion. EPA-approved sampling,
analytical, and quality assurance and quality control (QA/QC)
procedures were followed to obtain reliable data. QA/QC
procedures are detailed in the Technology Evaluation Report.
Review of Treatment Results
This section summarizes the results of both critical and
noncritical parameters for the CAV-OX* demonstration, and
evaluates the technology's effectiveness in treating groundwater
contaminated with VOCs. Data are presented in graphic or
tabular form. For samples with analyte concentrations at
nondetectable levels, one-half the detection limit was used as
the estimated concentration. However, if more than one replicate
sample had concentrations at nondetectable levels, using one-
half the detection limit as the estimated concentration for all
such replicable samples would significantly reduce the standard
deviation of the mean and would affect the statistical inferences
made. For this reason, 0.5,0.4,0.6, and 0.4 times the detection
limit were used as estimated concentrations for the first, second,
third, and fourth replicate samples, respectively.
Throughout the demonstration only two contaminants, TCE
and benzene, were detected in the influent at levels well above
target levels. Figure B-4 shows the influent concentrations of
benzene and TCE. Figure B-5 shows the influent concentrations
of ethylbenzene, toluene, and xylene. Toluene, ethylbenzene,
and xylene were present in the influent; however, because these
VOCs were present in relatively low levels compared to TCE
and benzene, the discussion of the CAV-OX* technology's
effectiveness pertains only to TCE and benzene.
50
-------
600
400
0)
0) =
0)
m
200
| Benzene
D TCE
2500
2000
1500
1000
500
LU =
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
Run
Figure B-4. Influent Concentrations - Primary Contaminants
<:o
20
0)
C 15
S-.
It
£
10
5
0
| Ethylbenzene
g Toluene
Q] Xylene
-
-
-
I 5n Q
1 2 3
4
nr
L
*™
n
I
,
[f
-i
f
56 7 8 9 10
P
Eh
11
i
12
^
p
-
-
-
~i
13 14 15
140
- 120
- 100
-60
40
20
Run
Figure B-5. Influent Concentrations - Secondary Contaminants
C
ID
51
-------
Summary of Results for Critical Parameters
Hydrogen Peroxide Effects
Critical parameters are those used to meet primary project
objectives. Table B-3 compares TCE and benzene removals
among the three treatment process configurations. Table B-4
compares TCE and benzene removal efficiencies among the
three treatment process configurations. Figure B-6 compares
the TCE removal efficiency of the three configurations. Figure
B-7 compares the benzene removal efficiency of the three
configurations. The major differences among the three
configurations involve UV output and flow rate. In general,
contaminant removal increased with UV output and with
decreased flow rates. However, the choice of a process depends
on site specific characteristics. For the conditions at Edwards,
the CAV-OX* I low-energy process would be adequate for a
desired flow rate of 0.6 gpm. Likewise, if a greater flow rate
is required, a 5-kW or 10-kW process may be preferable.
While operating under the preferred conditions, all
CAV-OX* process effluents met State of California drinking
water action levels and federal drinking water MCLs for BTEX
at the 95 percent confidence level. Effluent from one
configuration of the CAV-OX® I process met State of California
drinking water action levels and federal drinking water MCLs
for TCE at the 95 percent confidence level. In addition, average
effluent contaminant values from the CAV-OX® II process, while
operating under the preferred conditions, met State of California
drinking water action levels and federal drinking water MCLs
for TCE. However, because of data variability, the effluent
did not meet the 95 percent confidence level for TCE. The
demonstration evaluated numerous operating conditions; not all
conditions meet these discharge limits. Figure B-8 summarizes
these results.
Figure B-9 shows the effects of flow rate variations on the
CAV-OX® I process for TCE removals. Figure B-10 shows
the effects of flow rate variations on the CAV-OX® I process
for benzene removals. Figure B-ll shows the effects of flow
rate variations on the CAV-OX® II process for TCE removals.
Figure B-12 shows the effects of flow rate variations on the
CAV-OX® II process for benzene removals. Overall contaminant
removal efficiency increased with a decrease in flow rate.
However, the choice of a CAV-OX* configuration depends on
site specific characteristics.
Summary of Results for Noncritical Parameters
The technology demonstration also evaluated analytical
results for several noncritical parameters, which are those used
to meet secondary project objectives. These results are
summarized below.
A secondary objective of the demonstration was to examine
the effects of different hydrogen peroxide doses on the efficiency
of the treatment process. To meet this goal, hydrogen peroxide
was added to the influent holding tank to achieve concentrations
of 0, 30, 60, and 90 mg/L. For runs 10, 11, and 12, Magnum
added a calculated hydrogen peroxide dose to the holding tank.
The hydrogen peroxide concentration was then measured using
a titanium complexary method (Boltz and Howell 1979).
Magnum then added more hydrogen peroxide or water to the
holding tank as necessary to reach the desired concentration.
However, because Magnum distrusted titanium complexary
method results, Magnum purchased a test kit based on a ferric
reaction and used it for runs 4, 5, 6, 7, 8, 9, and 14. Hydrogen
peroxide was not added for runs 1, 2, 3, 13, and 15.
Results obtained using the Boltz and Howell method better
reflect the actual available hydrogen peroxide in each sample
for two reasons. First, the Boltz and Howell method is
straightforward. Titanium and peroxide ion form stable peroxo
complexes with a typical structure of [Ti(O2)OH(H2O)]+. The
overall ferric reaction is also simple:
H2O2
2Fe2+ -» 2OH+2Fe3+
The mechanism of this reaction is not simple, however,
because it involves free radicals. Therefore many other reactions
may occur. One well known reaction occurs in the presence of
oxygen and organics. The oxygen reacts with the organic free
radical to create organic peroxide radicals (RO-); these radicals
oxidize ferrous iron to make a hydroperoxide (ROOH), which
will react with more ferrous iron. The overall reaction, which
results in a falsely high analysis result, is shown below.
O2 + 4Fe2+ + 4H+ -> 4Fe3+ + 2H2O
Second, hydrogen peroxide was added to the influent holding
tank during the demonstration. The water in the tank not only
contained organic matter and some metal ions, but also was
exposed to air. Therefore, the actual hydrogen peroxide content
of the influent began declining upon contact. The rate of decline
of hydrogen peroxide depends on the rate of the free radical
generation, which is influenced by many factors. Therefore,
the possibilities for side reactions in the ferric reaction are much
greater than those with the Boltz and Howell method.
Also, the chemistry involved in the CAV-OX® process is
not at equilibrium. The composition of the water in the process
continuously changes; therefore, peroxide measurements taken
at different times, and possibly from different places within
the tank, will differ. There is no direct correlation of the time
and location of samples analyzed by the two methods.
52
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Table B-3. Contaminant Removal
Run
Influent
TCE
(f&L)
Benzene
(fig/L)
Hydrogen
Peroxide
Level
(mg/L)
CAV-OX*!
Flow Effluent
(apm)
TCE
Benzene
(P9/L)
CAV-OX*II
Flow (gpm) Effluent
TCE Benzene
5-kW 10-kW 5-kW 10-kW 5-kW 10-kW
Low Hydrogen
1 1,975
2 2,000
3 1, 775
Peroxide Dose
263
265
243
0
0.4
0.4
0.6
1.5
1.5
1,450
1,400
1,550
280
285
268
Medium Hydrogen Peroxide Dose
4 1,925
5 1,575
6 1,600
7 1,975
8 1,850
9 1,800
High Hydrogen
10 1,675
11 1,475
12 1,525
285
333
355
503
283
433
Peroxide Dose
252
240
250
4.9
4.9
5.9
5.9
6.0
6.1
23.4
33.1
48.3
1.5
1.5
0.5
0.7
0.7
1.5
0.6
0.5
0.6
550
603
57.5
255
225
710
1.64
1.95
4.77
32.5
61.3
2.28
17.5
8.7
60.3
ND
ND
ND
Vendor Selected Condi/tons
13 2,000
500
1.8
NA"
NA"
NA"
2.0
1.6
3.9
4.0
3.9
1.5
1.9
1.9
4.0
2.0
1.6
1.4
1.9
2.0
1.6
4.0
3.9
3.4
1.4
2.0
1.9
4.0
2.1
1.5
1.4
1.9
235
119
608
235
235
6.55
43.0
29.0
248
5.3
6.01
2.88
388
28.0
76.8
248
35.8
46.3
10.1
15.6
13.5
20.3
5.23
11.9
5.0
47.8
160
135
223
29.3
34.8
1.72
3.1
3.3
28.3
1.24
1.4
ND
308
95.3
84.5
163
3.8
7.23
2.06
2.4
2.08
2.38
1.12
2.78
ND
198
14 * 1,675 410
9.1
NA" NA" NA"
NA" 7.9 NA" 141 NA" 17.3
15''' 2,000
468
1.0
NA" NA" NA"
A/XT
0.8 2,025''" 73.1 468*'" 21.4
Notes: * Influent pH adjusted
" CA V-OX" I and 5-kW CA V-OX* II not operated
c CAV-OX*II operated at 2.5 kW
d Sample collected after the cavitation chamber prior to UV reactor
NA = not applicable
ND = not detected
gpm = gallons per minute
mg/L = milligrams per liter
fjg/L = micrograms per liter
kW = kilowatts
53
-------
Table B-4. Contaminant Removal Efficiency
Run
Hydrogen
Peroxide
Level
(mg/L)
Flow (gpm)
CAV-OX*!
Removal Effficiency (%)
TCE
Benzene
Low Hydrogen Peroxide Dose
1
2
3
Medium
4
5
6
7
8
9
0
0.4
0.4
Hydrogen
4.9
4.9
5.9
5.9
6.0
6.1
0.6
1.5
1.5
Peroxide Dose
1.5
1.5
0.5
0.7
0.7
1.5
26.6
30.0
12.7
71.4
61.7
96.4
87.1
87.8
60.6
0
0
0
88.6
81.6
99.4
96.5
96.9
86.7
High Hydrogen Peroxide Dose
10
11
12
Vendor
13
14'
15"
23.4
33.1
48.3
0.6
0.5
0.6
99.9
99.9
99.7
99.9
>99,9
>99.9
Selected Conditions
1.8
9.1
1.0
NA"
NA"
NA "
NA "
NA "
NA "
NA "
NA "
NA "
CAV-OX*!!
Flow (gpm)
5-kW 10-kW
2.0 2.0
1.6 1.6
3.9 4.0
4.0 3.9
3.9 3.4
1.5 1.4
1.9 2.0
1.9 1.9
4.0 4.0
2.0 21
1.6 1.5
1.4 1.4
1.9 1.9
NA " 7.9
NA " 0.8
Removal Efficiency (%)
TCE
5-kW 10-kW
88.1
94.1
65.8
87.8
85.1
99.6
97.8
98.4
86.2
99.7
99.6
99.8
80.1
NA
NA
98.6
99.2
86.1
98.1
97.1
99.4
99.2
99.3
98.9
99.7
99.2
99.7
97.6
' 916
"-" 96.3
Benzene
5-kW
39.0
49.1
8.2
89.7
89.5
99.5
99.4
98.8
93.5
99.5
99.4
99.8
38.5
NA "
NAb'd
10-kW
63.7
68.1
33.0
98.7
97.8
99.4
99.5
99.3
99.5
99.5
98.8
99.8
60.5
95.8
95.4
Notes: ' Influent pH adjusted
" CAV-OX* I and 5-kW C/AV-OX® // not operated
c CAV-OX»II operated at 2.5 kW
d Sample collected after the cavitation chamber prior to UV reactor
NA = not applicable
gpm = gallons per minute
mg/L = milligrams per liter
kW = kilowatts
54
-------
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TL = 5
TL = 20
TL = 680
TL = 1750
Hydrogen Peroxide
Concentration - 48.3 mg/L
ND ND ND
ND ND ND
TCE
Benzene
Toluene
Ethylbenzene
0.15
Xylene
L«g«id
Low Energy 0.6 gpm
5-kW High Energy 1.4 gpm
10-kW High Energy 1.4 gpm
ND = Non detect
TL = Target level
UCL = Upper confidence level
Figure B-B. Comparison of 95 Percent UCLs for Effluent VOC Concentrations with Demonstration Target Levels (Run 12)
The demonstration results show that removal efficiency
increased with the addition of hydrogen peroxide. However,
Magnum reports that this increase in efficiency is limited and
that efficiency decreases beyond some level of hydrogen peroxide
addition. The demonstration did not fully evaluate enough
hydrogen peroxide levels to determine the concentration at which
efficiency decreases with additional hydrogen peroxide. Table
B-4 shows the increase in removal efficiencies with increased
hydrogen peroxide dose.
pHEffects
For runs 14 and 15 (in which pH was varied) only acid
addition is considered because of the high bicarbonate levels in
the groundwater. Because carbonate and bicarbonate scavenge
hydroxyl radicals, acid addition may improve process
performance by shifting the carbonate equilibrium to carbonic
acid. However, during the two runs in which pH was varied,
other parameters were also varied; therefore, definitive
conclusions cannot be drawn about the effects of pH.
Vendor-Selected Conditions
Runs 13,14, and 15 were conducted under conditions chosen
by Magnum. For these runs Magnum chose not to operate the
CAV-OX® I low-energy process.
Run 13 repeated the conditions of Run 1 (a previous run
with no hydrogen peroxide added). The results of these runs
agree and show that although some contaminants are removed,
hydrogen peroxide is vital to achieve high removal efficiencies.
For Run 14, Magnum chose to operate with a hydrogen
peroxide concentration of 9.1 mg/L and a flow rate of 8 gpm.
Results of this run showed that the increased hydrogen peroxide
levels did not compensate for the increased flow rate (and
therefore decreased retention time) in the process. Also, since
the pH of the influent was lowered, definitive conclusions cannot
be based on this run.
For Run 15, Magnum chose to operate the CAV-OX* II
reactor at 2.5 kW with no added hydrogen peroxide and a flow
rate of 1 gpm. The purpose of performing this run under these
operating conditions was to examine the effects of the cavitation
chamber. Samples were collected from three locations: (1) at
the intake to the process, (2) after the cavitation chamber but
before the UV reactor, and (3) after the UV reactor. Run 15
results indicated no immediate decrease in contamination in the
water exiting the cavitation chamber. Magnum reports that a
holding time of about 1 hour after the water exits the cavitation
chamber is optimal for removal of contaminants in the cavitation
chamber. However, the equipment demonstrated at Edwards
57
-------
1.5gpm
0.7 gpm
0.5 gpm
710
255
Run 7, 87
57.5
Run 6, 9(i.4% Removal Efficiency
1% Removal Efficiency
Run 9, 60.6% Remo\
Hydrogen Peroxide Co ncentration =6.0 mg/L
al Efficiency
200
400
600
800
1000
TCE
Figure B-9. CA V-OX® / Flow Variations on Trichloroethene Removals
1.5 gpm -
0.7 gpm
0.5 gpm
,_ _ Run 7, 96.5% Removal Efficiency
1 / ,O
Run 6, 99.4
2.28
i* Removal Efficiency
Run 9, 86.1% F emoval Efficiency
Hydrogen Peroxide Q
ncentration -6.0 mg/L
20
40
60
80
100
Benzene
Figure B-10. CA V-OX® / Flow Variations on Benzene Removals
58
-------
4.0 gpm
Run 3, 65.8% Removal Efficiency
Run 3, 86.1% R« moval Efficiency
Run 1, 88.1% Removal Efficiency
2.0 gpm
^28
Run 1, 98.6% Relmoval Efficiency
Run 2, 94.1% Romoval Efficiency
1.6 gpm
$16.8
Run 2, 99.2% Removal Efficiency
Hydrogen Peroxide
Concentration ^Omg/L
Legend
5-kW High Energy
10-kW High Energy
200
400
600
800
1000
TCE
Figure B-11. CAV-OX® II Flow Variations on Trichloroethene Removals
4.0 gpm
Run 3, 8.2% Removal Efficiency
223
Run 3, 33.0% Removal Efficiency
Run 1, 39.0% Removal Efficiency
2.0 gpm
160
Run 1, 63.7% Re noval Efficiency
Run 2, 49.1% Re noval Efficiency
1.6 gpm
Concentraiion
Run 2, 68.1% Removal Efficiency
Hydrogen,
'erixide
Omg/L
Legend
5-kW High Energy
10-kW High Energy
100 150
Benzene
50
Figure B-12. CA V-OX® // Flow Variations on Benzene Removals
200
250
59
-------
The focus of a SITE demonstration is to examine a
technology in its entirety, not to study its individual components.
The effects of captation alone, therefore, were not fully evaluated
during the CAV-OX® demonstration. Results of other studies
conducted by Magnum concerning the effects of cavitation alone,
independent of the SITE demonstration, are included in Appendix
A and Appendix C.
Additional Noncritical Parameters
Additional analytical results for several noncritical
parameters are summarized below.
In general, GC/MS analysis of influent and effluent samples
for VOCs indicated that several new target compounds or
tentatively identified compounds (TIC) were formed during the
treatment. Acetone and 2-butanone concentrations were
generally higher in the effluent than in the influent Also, several
unknown TICs were identified in both the influent and effluent
samples. However, vinyl chloride and 1,1-dichloroethanewere
not formed during treatment.
GC/MS analysis of influent and effluent samples for SVOCs
revealed only phenol, 2-methylphenol, and bis(2-
ethylhexyl)phthalate. The highest concentration found was 11
ug/L, and these compounds were found in both the influent and
effluent samples in similar concentrations. As with the VOC
analysis, several unknown TICs were identified in both the
influent and effluent samples.
During Runs 13, 14, and 15, bioassay tests were performed
to evaluate the acute toxicity of influent and effluent samples.
Two freshwater test organisms, a water flea (Ceriodaphnia
dubia) and a fathead minnow (Pimephalespromelas), were used
in the bioassay tests. Toxicity was measured as the lethal
concentration at which 50 percent of the organisms died (LC50)
and was expressed as the percent of effluent (or influent) in the
test water. One influent and one effluent sample was tested in
each run. Bioassay analyses showed influent and effluent from
Run 13 to be nontoxic to the fathead minnow and moderately
toxic to the water flea. Bioassay analyses also showed influent
and effluent from Run 14 to be toxic to both the fathead minnow
and the water flea, and that influent from Run 15 was nontoxic
to the fathead minnow and toxic to the water flea. Effluent
from Run 15 was toxic to both the fathead minnow and the
water flea. Bioassay analyses of water from runs with low
levels of hydrogen peroxide (Run 13) showed that the CAV-OX*
process effluent was nontoxic to the fathead minnow but
moderately toxic to the water flea, while bioassay analyses of
water from runs with hydrogen peroxide (Run 14) showed that
the CAV-OX® process effluent was toxic to both the fathead
minnow and the water flea. Comparison of effluent toxicity
data with that of hydrogen peroxide in the effluent (10 mg/L)
indicates that effluent toxicity may be due partially to hydrogen
peroxide rather than CAV-OX® treatment by-products.
Additional studies are needed to draw any conclusion on any
effluent toxicity related to hydrogen peroxide.
Samples were also analyzed for iron and manganese. Iron
concentrations in the influent ranged from 180 to 462 ug/L, while
concentrations in the effluent ranged from 217 to 512 ug/L.
Manganese concentrations in the influent ranged from 662 to
694 ug/L, while concentrations in the effluent ranged from 686
to 740 ug/L. These results indicate that the CAV-OX® process
did not remove iron or manganese because these metals were
present at similar levels in the influent and the effluent.
No significant changes inpH, alkalinity, hardness, or specific
conductance were observed during treatment.
Total recoverable petroleum hydrocarbons (TRPH) were
found in the influent at concentrations of 0.64 to 1.15 mg/L.
TRPH concentrations in the effluent ranged from below detection
limits to 0.78 mg/L.
Turbidity readings for the influent samples ranged from 2.97
to 3.58 nephelometric turbidity units (NTU). Readings for the
effluent samples ranged from 2.07 to 3.38 NTUs.
In the CAV-OX* I process, the water temperature increased
at a rate of about 0.26 °F per minute of UV exposure. In the 5-
kW CAV-OX® II process, the water temperature increased at a
rate of about 2.36 °F per minute of UV exposure. In the 10-
kW CAV-OX* II process, the water temperature increased at a
rate of 4.29 °F per minute of UV exposure. Since the equipment
was exposed to the surrounding environment, the temperature
increase may vary depending upon the ambient temperature or
other atmospheric conditions.
Electricity is the only utility required for the CAV-OX®
process. The electricity demand was 2.2 kW for the CAV-OX®
I process, 6.4 kW for the 5-kW CAV-OX* II process, and 13
kW for the 10-kW CAV-OX® II process.
Hydrogen peroxide, the only process chemical used in the
CAV-OX® process, was used at a rate of between 0 and 48.3
mg/L.
After operating about 2 weeks, no scaling was observed on
any of the UV tubes at the end of the demonstration. Magnum
reports that scaling is not a concern for the CAV-OX* process.
Conclusions
The following preferred operating conditions were
determined for the CAV-OX® I low-energy process: (1) an
influent hydrogen peroxide level of 23.4 mg/L and (2) a flow
rate of 0.6 gpm. At these conditions, TCE and benzene levels
in the effluent were generally below target levels (5 ug/L and 1
ug/L, respectively). The average removal efficiencies for TCE
and benzene were both greater than 99.7 percent.
60
-------
The following preferred operating conditions were
determined for both the 5-kW and 10-kW CAV-OX* II
configurations: (1) an influent hydrogen peroxide level of 48.3
mg/L and (2) a flow rate of 1.4 gpm. At these conditions, TCE
and benzene levels in the effluent were generally below the
target level. The average removal efficiencies for TCE and
benzene were about 99.7 and 99.8 percent, respectively.
While operating under the preferred conditions, all
CAV-OX® process effluents met State of California drinking
water action levels and federal drinking water MCLs for BTEX
at the 95 percent confidence level. One configuration of the
CAV-OX* I process effluents met State of California drinking
water action levels and federal drinking water maximum
contaminant levels for TCE at the 95 percent confidence level.
In the CAV-OX* I low-energy process, the 5-kW CAV-OX*
II high-energy process, and the 10-kW CAV-OX* II high-energy
process, water temperature increased at an average rate of about
0.26 °F, 2.36 °F, and 4.29 °F per minute of UV exposure,
respectively. Since the equipment was exposed to the
surrounding environment, the temperature increase may vary
depending upon the ambient temperature or other atmospheric
conditions.
After operating about 2 weeks, no scaling was observed on
any of the tubes at the end of the demonstration.
References
Boltz, D.F., and J.A. Howell. 1979. Colorimetric
Determination of Non-Metals. John Wiley & Sons, New
York, New York.
The Earth Technology Corporation. 1992. "Benzene Plumes,
Fall 1991". Prepared for Edwards Air Force Base,
California. October.
Engineering-Science. 1988. "PhaseIV-InstallationRestoration
Program Assessment of Site 16 Recovery Well Process Final
Quality Control Plan and Sampling Plan." Prepared for
Edwards Air Force Base, California. December.
61
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Appendix C
Case Studies
Note: This appendix presents nine case studies provided by
Magnum Water Technology (Magnum) on the application
of the CAV-OX® process to contaminant streams. Claims
and interpretations of results in this appendix are made by
Magnum and may not be substantiated by test or cost data.
This appendix has been edited only so that format is consistent
with the document.
Introduction
Table C-l summarizes the results of nine case studies
provided by Magnum involving both pilot- and full-scale units
treating contaminated groundwater and industrial wastewaters.
Magnum provided all case studies as additional performance
data for the CAV-OX* process. Contaminants of concern
included pentachlorophenol (PCP), total petroleum hydrocarbons
(TPH), benzene, toluene, ethylbenzene, and xylenes (BTEX),
biochemical oxygen demand (BOD), total organic carbon (TOC),
atrazine, cyanide, phenol, and the bacterium Salmonella.
In case studies involving PCP, TPH, and BTEX, the
CAV-OX* process reduced the levels of these contaminants in
various aqueous phases by 96 to 99.94 percent.
Two case studies investigated BOD removal. In the first of
these, the CAV-OX* process reduced BOD in resin plant effluent
by 94.1 percent. In the second, BOD in contaminated seawater
was reduced by 83.3 to 88.4 percent. In the first case study
hydrogen peroxide was added; in the second hydrogen peroxide
was not added and ultraviolet (UV) treatment was not used.
One case study involved groundwater contaminated with
the herbicide atrazine. The CAV-OX® process reduced atrazine
levels from 1,000 micrograms per liter (ug/L) to 200 ug/L, a
reduction of 80 percent. Although atrazine could have been
reduced further, the customer in this case determined that 200
Ug/L was acceptable.
The CAV-OX* process has also been used to treat
wastewater contaminated with potassium cyanide. In this case
study, the process consistently oxidized potassium cyanide to
nondetectable levels with retention times of less than 4 minutes
and hydrogen peroxide levels as low as 20 milligrams per liter
(mg/L). Using cavitation and UV radiation only, without adding
hydrogen peroxide, potassium cyanide levels were reduced by
46 percent.
In another case study, the CAV-OX* process reduced levels
of Salmonella in city water from 2,000,000 colony-forming units
per milliliter (CFU/mL) to 0.8 CFU/mL without hydrogen
peroxide addition. After injecting the water with 80 mg/L
hydrogen peroxide, Salmonella levels were reduced from
1,900,000 CFU/mL to 0.01 CFU/mL.
In the final case study phenol was reduced from 20 parts
per million (ppm) (with 60 ppm hydrogen peroxide) to
nondetectable levels at a flow rate of 2 gallons per minute (gpm)
and to 0.8 ppm at a flow rate of 6 gpm.
Some case studies identify the cost (in October 1993 dollars)
to treat 1,000 gallons of influent, an industry-standard method
of presentation. Magnum's method accounts for the following
operating costs:
Operating chemical usage
Power consumption by ultraviolet (UV) lamps and
centrifugal pump
• Maintenance allowance costs
Amortization of capital equipment over 5 years
The cost per 1,000 gallons is the total of these costs. Costs
from the case studies ranged from $1.62 to $1.93 per 1,000
gallons of water containing organic contaminants. For one case
study, the cost to reduce BOD using only the cavitation chamber
(no UV and no hydrogen peroxide) was $0.13 per 1,000 gallons.
63
-------
Table C-1. Case Study Summary
Case Study
Facility
Contaminants
Results
C-1
C-2
C-3
C-4
C-5
C-6
C-7
C-8
C-9
Wood-treating Superfund
site, Pensacola, Florida
Chevron service station,
Long Beach, California
Presidio Army Base, San
Francisco, California
Pentachlorophenol (PCP),
polynuclear aromatic
hydrocarbons (PAH)
Total petroleum
hydrocarbons (TPH);
benzene, toluene,
ethylbenzene, and xylenes
(BTEX)
TPH, BTEX
Chemical plant, East Coast
U.S.
Biochemical oxygen
demand (BOD)
Mannesman/? Anlagenbau, Atrazine
Salzburg, Austria
Steel mill, South Korea Cyanide, phenol
Chicken farm, Virginia Salmonella
Southern California
Edison, Los Angeles,
California
Corporation Mexicana de
Investigation en Materials,
S.A. de C.V. (CMIMSA)
BOD
Phenol, Pharmaceuticals
PCP reduced by 96
percent
TPH reduced by 99.94
percent
Ethylbenzene and TPH
reduced to nondetectable
levels
BOD reduced by 94.1
percent
Atrazine reduced from
1,000 micrograms per liter
(uo/L) to 200 ug/L
Cyanide reduced by 55
percent using captation
only and greater than 99.9
percent using cavitation
and UV radiation
Samonella reduced from
2,000,000 colony forming
units per milliliter
(CFU/mL) to 0.8 CFU/mL
without hydrogen peroxide
addition; reduced to 0.01
CFU/mL after hydrogen
peroxide addition
BOD reduced by 83.3 to
88.4 percent using
cavitation only
At high flow rates phenol
was reduced to
nondetectable levels
CASE STUDY C-1:
Pensacola, Florida
Introduction
Wood Treating Superfund Site, Equipment
In mid-1992, Magnum was asked to supply a CAV-OX*
process to reduce PCP in a leachate discharged from a soil
washing process. The soil washing process was part of a
demonstration sponsored by the U. S. Environmental Protection
Agency (EPA) to evaluate the remediation of this site, which
had been in operation for more than 40 years before it was
designated a Superfund site.
Magnum delivered both a CAV-OX* I low-energy unit and
a CAV-OX* II high-energy unit. The units could be run in series,
parallel, or independently through suitable valving.
The CAV-OX* I low-energy unit consisted of a 2-
horsepower centrifugal pump, cavitation chamber, recycle loop,
six 60-watt lamps in a 6-foot stainless steel reactor and associated
controls, UV ballasts, function lamps, and circuit breakers. The
CAV-OX® II high-energy unit used the same centrifugal pump,
cavitation chamber, and recycle loop but had an independent
power supply for the 5-foot high-energy reactor with its 2.5- or
5-kilowatt (kW) lamp.
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The equipment was shipped using a common carrier and
delivered to the site over a weekend. It was installed and tested
the following Monday. The next 5 days were full test days lasting
from 8 to 12 hours. The CAV-OX* equipment was operable
100 percent of the time and had no failures of any kind.
Methodology
The customer decided that the leachate would receive
minimal pretreatment, to develop a worst-case scenario for
evaluating the technology. Because the leachate was a thin slurry
instead of a contaminated water stream, it was treated with high
levels of hydrogen peroxide (2,000 to 4,000 mg/L), followed by
treatment in the CAV-OX® II high-energy process. Minimum
pretreatment on future test runs, if needed, would consist only
of pH adjustment, followed by minimal cartridge filtration using
swimming pool filters.
A 500-gallon polyethylene holding tank was used to collect
leachate from the soil washing process (without pretreatment)
and served as a recycle vessel for the batch process test.
Preliminary tests were run to evaluate process efficiency in
reducing PCP and to determine optimal operating parameters.
The initial runs showed that little UV was being transmitted
and that most PCP destruction was taking place in the cavitation
chamber, aided by hydrogen peroxide addition. PCP was
generally reduced by 22 to 50 percent in the initial runs.
However, for runs in which flow-through was reduced or
recycling increased, increasing the UV intensity raised the
effluent temperature from 100 °F to 150 °F and above. The
temperature rise caused the PCP concentration in the effluent to
increase dramatically, often doubling or tripling in the influent.
The higher concentrations resulted from the slurry releasing
additional contaminants as the temperature rose.
A series of tests on the process stream, without pretreatment,
was made with recycle times of 30 minutes, 60 minutes, and 90
minutes. On the basis of these tests, it was decided that adjusting
the pH of the process stream from 9 to 5.5 would cause
flocculation and sedimentation in the holding tank, resulting in
a clearer influent to the CAV-OX* process.
Results
After adjusting the pH of the process stream, one subsequent
test run showed a 96 percent reduction in PCP levels. It is
important to note that while PCP levels in the influent varied
from 900 to 15,000 ug/L, an additional load of polynuclear
aromatic hydrocarbons (PAH) ranging from 16,000 to 128,000
ug/L was also present in the influent.
CASE STUDY C-2: Chevron Service Station, Long
Beach, California
Introduction
In late 1990, a CAV-OX* I low-energy process was installed
at a former Chevron service station to remediate groundwater at
the site. Gasoline storage tanks at the site had leaked for several
years, resulting in a groundwater contaminant plume that was
migrating toward adjoining commercial property.
Since the plume had spread over a large area, 12 wells
were drilled at its periphery to feed the overall treatment process
and prevent the plume from spreading further. The CAV-OX*
I process was to operate at 10 gpm, in order to reduce TPH
from 200 mg/L to a level that met local regulations.
Equipment
The CAV-OX* I low-energy process used for this project
was rated at 10 gpm and included a cavitation chamber, a
centrifugal pump, a hydrogen peroxide injection process, and
twelve 60-watt UV lamps housed in two stainless steel reaction
chambers. A control panel housed the necessary wiring, UV
ballasts, circuit breakers, and control switches. Figure C-l is a
photograph of the process.
Magnum worked closely with the site consultant and the
client to design the pretreatment process. The final pretreatment
process system consisted of a closed, pressurized design,
preventing volatile organic compounds (VOC) from being
released to the environment. The entire unit was housed in a
15-foot-by-12-foot enclosure at the corner of the property.
Methodology
Influent was drawn from the 12 wells using bladder pumps
driven by an on-site compressor, which also supplied air to
maintain 4 pounds per square inch (psi) of pressure on the sealed
holding tank. Influent was pumped through two 3.5-cubic-foot
media filters and forwarded to the holding tank. The liquid level
in the holding tank was maintained by a level-control process,
which was coordinated with an on-off control valve to the
centrifugal pump. This centrifugal pressure pump developed
64 psi in the cavitation chamber. Groundwater was fed from the
cavitation chamber at about 8 psi to the UV reactors. A recycle
process allowed the groundwater to be returned upstream for
additional treatment and functioned as a flow control for process
throughput.
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Figure C-1. Photograph of CAV-OX * Process
66
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Operations
During the 2 years required to remediate the site, the
CAV-OX* I low-energy process was maintained by the site
consultant's technical staff. After process start up, a trained
technician collected effluent samples and serviced the process
every 20 to 30 days. The CAV-OX* I low-energy process was
operational 99.9 percent of the time over the 2-year period.
Initial problems with components in the air pressure process
prevented the process from maintaining consistent operating
conditions during the first few months. These problems were
eventually solved.
Because of potential variations in influent quality, 400
pounds of activated carbon was included in the process to handle
free product that might pass through the CAV-OX* I low-energy
process. The carbon was replaced once during the 2-year period.
The UV lamps were replaced twice during the 2-year period.
In addition, one quartz tube was broken when it was removed
to be examined for exterior fouling, and was replaced. The quartz
tubes never showed any indication of scaling, although the
influent quality varied widely and appeared black at times
because of apparent biological activity.
In early 1992, the 20 mg/L hydrogen peroxide injection
before the centrifugal pump inlet was discontinued because tests
indicated that it was unnecessary.
Results
As of late 1992, when the CAV-OX* I low-energy process
was shut down, the influent TPH level had been reduced from
190,000 ug/L to 120 ug/L, a reduction of 99.94 percent. The
overall cost was $1.62 for every 1,000 gallons of groundwater
treated.
CASE STUDY C-3: Presidio Army Base, San Francisco,
California
Introduction
A 20-gpm CAV-OX* I low-energy process was installed to
remove VOCs from groundwater at a service station on the
Presidio Army Base in San Francisco, California.
Equipment
The Model 2662.5 CAV-OX* I low-energy process installed
at the site consisted of the cavitation chamber, a centrifugal
pump, a hydrogen peroxide injection process, thirty-six 60-watt
UV lamps housed in six stainless-steel reactors, a control panel
with UV ballasts, and necessary switches, relays, and indicator
lamps.
The CAV-OX* I low-energy process was combined with
other equipment, including a vacuum extraction process for
soil remediation, groundwater pumps and manifold, an influent
holding tank with level controls, and the necessary electrical
process and interlocks.
Table C-2. Groundwater Sampling Results, August 20, 1990
Sample Benzene Toluene Xylenes Ethyl- TPH
Point benzene
Influent
Effluent
450
44
1.9
100
1.5
25
ND
80
ND
Notes:
ND = Not detected
Results
Results of samples collected after installation, start up, and
training are shown in Table C-2.
Tests performed in 1993 show that contaminants in
groundwater at the site have been reduced dramatically.
However, contaminant levels in soil require further remediation
using the vacuum extraction process in conjunction with the
CAV-OX* I low-energy process. The CAV-OX* I low-energy
process may need to be operated intermittently if contaminants
in the soil are further released into the groundwater.
The CAV-OX* I low-energy process was not installed under
a protective cover at this site and has been exposed to the
elements for the last 3 years. The UV components and parts not
made of stainless steel have deteriorated somewhat; however, a
protective cover will prevent this deterioration.
The overall cost was $1.75 for every 1,000 gallons of
groundwater treated.
CASE STUDY C-4: Chemical Plant, East Coast U.S.
Introduction
In 1992, a major U.S. resin manufacturer contracted with
Magnum to conduct a pilot study for remediating its plant
effluent. This waste stream was common to several of the
manufacturer's facilities on the east coast of the United States.
Plant procedures required that the effluent be shipped off site
for treatment, resulting in high costs and potential liabilities.
The customer agreed that the effluent was not suitable for
treatment by standard advanced oxidation systems because of
the type of contaminants and the high contaminant levels. The
purpose of the pilot study was to determine how the CAV-OX*
process could reduce contaminant levels in order to reduce
overall disposal costs.
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Equipment
Equipment
A CA V-OX* II high-energy pilot unit was used for this study
because of the types and concentrations of contaminants in the
effluent. The unit consisted of a double reactor with a total UV
output of 10 kW. Each 5-foot reactor had a 2.5- or 5-kW UV
lamp and an independent power supply. The unit also included
a 2-horsepower centrifugal pump, a cavitation chamber, a recycle
loop, and a control panel with associated switches, indicator
lamps, and circuit breakers.
Because the CAV-OX* II high-energy pilot unit consists of
full-scale modules operating at 3 gpm, results from this study
can be directly extrapolated to full-scale 10-gpm or 25-gpm
industrial processes.
Methodology
First, 250 gallons of effluent was placed in a holding tank.
The effluent was clear, somewhat viscous, and irritating to
mucous membranes, with a strong odor. Next, hydrogen
peroxide was added to the holding tank to achieve a concentration
of 100 mg/L, resulting in an opaque, beige colored solution.
Because this would decrease transmission of the UV radiation,
most of the contaminant destruction would have to occur in the
cavitation chamber. The test procedure was altered to allow
maximum flow through the cavitation chamber; the flow was
then directed through the UV reactors at 0.75 gpm.
Results
BOD was the primary parameter of concern; however, the
C A V-OX* II high-energy process treated all constituents in the
influent. Although nontargeted contaminants absorbed a
significant amount of energy from the cavitation chamber and
UV lamps, BOD in the treated effluent was reduced by 94.1
percent.
CASE STUDY C-5: Mannesmann Anlagenbau,
Salzburg, Austria
Introduction
Mannesmann Anlagenbau (Mannesmann) of Salzburg,
Austria, contracted with Magnum to treat groundwater
contaminated with the herbicide atrazine. Atrazine is
manufactured and sold worldwide by Ciba-Geigy Corporation
(Ciba). Tests were conducted at Magnum's El Segundo,
California, facility using atrazine samples supplied by Ciba. Ciba
also provided technical support.
A C A V-OX* I low-energy process with a 3-gpm flow was
used for these tests. The process consisted of nine 45-watt
lamps contained in three stainless steel reactors, a hydrogen
peroxide injection unit, a centrifugal pump, and the cavitation
chamber.
Methodology
The atrazine solution was mixed according to Ciba's
recommendations and to Mannesmann's recommended level of
1 mg/L. The mixture was fed to the CAV-OX® I low-energy
process from a 150-gallon holding tank.
The solution was processed using various protocols.
Different flow rates and treatment levels were tested to determine
an ideal protocol. However, the cost of laboratory analyses
limited further optimization.
Results
Samples were sent to a local certified laboratory chosen by
Mannesmann. Although atrazine could have been reduced to
nondetectable levels, Mannesmann decided that the 200 ug/L
achieved in the first test, a reduction of 80 percent, was
acceptable.
CASE STUDY C-6: Steel Mill, South Korea
Introduction
A major steel mill in South Korea had been disposing of
wastewater contaminated with phenol and cyanide by discharging
it to holding ponds. South Korean government regulations now
prohibit this disposal method. Tests were conducted at
Magnum's El Segundo, California, facility to demonstrate the
CAV-OX* process's ability to remove these contaminants. In
addition, a pilot-scale CAV-OX* unit was purchased and installed
at the steel mill to demonstrate the technology on site.
Equipment
Three configurations of CAV-OX* equipment were tested:
A CAV-OX* I low-energy laboratory-scale unit
A CAV-OX* I low-energy pilot-scale unit
A CAV-OX* II high-energy unit
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The laboratory-scale unit consisted of a 55-gallon, stainless
steel holding tank, a 1.5-horsepower centrifugal pump, and
plumbing and bypass lines into three UV reactors. Each reactor
was 3 feet long with three 45-watt lamps, for a total UV output
of 405 watts. The reactors were plumbed in series. Effluent
from the reactors flowed through the discharge lines.
The Model 3162 pilot-scale unit, with a rated capacity of 3
gpm, consisted of the same holding tank, a 2-horsepower
centrifugal pump, and one 6-foot, low-pressure UV reactor with
six 60-watt lamps, for a total UV output of 360 watts. The unit
also included a control panel with the necessary electrical and
electronic circuits and electronic ballasts. Effluent from the
reactors was either directed to the discharge lines or to the
CAV-OX* II high-energy unit.
The CAV-OX* II high-energy unit was operated either in
series with the output from the CAV-OX* I units or
independently. In the latter case, it consisted of a cavitation
chamber, centrifugal pump, and control panel. It also had an
independent power supply for operating the high-energy lamps.
Its UV reactor held one UV lamp rated at 2.5 or 5 kW.
Methodology
Wastewater from the steel mill was stored in the holding
tank prior to entering the CAV-OX® unit. Potassium cyanide
powder was added to the holding tank to introduce the desired
concentration of cyanide. Three concentrations of potassium
cyanide were used: 0.65 mg/L, 1 mg/L, and 50 mg/L. Phenol
was also added to the holding tank, resulting in an influent
concentration of 11 mg/L. One test treated 20 mg/L phenol,
while other tests treated 200 mg/L phenol.
Finally, hydrogen peroxide was added to the holding tank.
The tank contents were then thoroughly mixed with a motor-
powered propeller.
Samples were collected at three points: the influent, the
first effluent sample from each unit, and the last effluent sample
from each unit. A Chemetrics K-8012 test kit was used to
measure phenol, and a Chemetrics K-3810 test kit was used to
measure cyanide. Tests for cyanide were run first, followed
by tests for phenol and then by tests for cyanide and phenol
combined. In addition, pH was measured using an EXTECH
pH meter, and flow rate was measured with a GPI electronic
digital flow meter. The first cyanide tests were conducted with
the CAV-OX* I low-energy unit.
Results
Cyanide, phenol, and combined cyanide/phenol tests were
run to determine the effectiveness of the CAV-OX* process in
destroying each contaminant.
Cyanide Tests
The CAV-OX* II high-energy process consistently oxidized
potassium cyanide to nondetectable levels with retention times
of less than 4 minutes and hydrogen peroxide levels as low as
20 mg/L. Using only cavitation and UV radiation, without
hydrogen peroxide, potassium cyanide levels were reduced by
46 percent. The effluent met discharge standards.
The CAV-OX® I low-energy pilot-scale unit oxidized
1 mg/L potassium cyanide to nondetectable levels under the
following conditions: 40 mg/L hydrogen peroxide, 0.75 gpm
flow rate, and 13 minutes retention time. Using 50 mg/L
hydrogen peroxide, a flow rate of 1 gpm, and a retention time of
10 minutes, 1 mg/L of cyanide was reduced by 70 percent.
Table C-3 lists additional representative results for the
CAV-OX® II high-energy and CAV-OX® I low-energy units.
The CAV-OX* I low-energy laboratory-scale unit showed
similar results. The total UV output of the laboratory unit was
360 watts instead of 405 watts.
Previous tests for another foreign customer, using the
CAV-OX® I low-energy pilot-scale unit but with sodium cyanide
as the contaminant, had similar results.
Phenol Tests
Table C-4 lists representative results of the phenol tests.
Combined Cyanide and Phenol Tests
Table C-5 lists representative results of the combined
cyanide and phenol tests.
Operating costs for the CAV-OX® I low-energy pilot-scale
unit are estimated at $1.93 per 1,000 gallons.
CASE STUDY C-7: Perdue Farms, Bridgewater, Virginia
Introduction
Chickens contaminated with the bacterium Salmonella are
a serious problem at U.S. chicken farms. Magnum conducted
tests in cooperation with Silliker Laboratories, a national
microbiology company, to demonstrate the CAV-OX* process's
ability to eliminate pathogens associated with chicken farming.
The test results were presented to several of the nation's largest
chicken farms.
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Table C-3. Cyanide Removals
Test
Flow (gpm) UV (Watts)
CAV-OX«1I High-Energy Process
1 2.5 2,860
2 0.75 2,860
3 1 5,360
4 2.5 5,360
5 2 5,360
CA V-OX1 Low-Energy Pilot-Scale Unit
1 2.5 360
2 1 360
3 2.5 360
4 0.75 360
5 0.75 0
6 1 360
Hydrogen Cyanide in
Peroxide Influent
(mg/L) (mg/L)
0 0.65
20 0.65
60 50
60 50
60 2
0 0.65
60 50
60 11
40 1
40 1
60 11
Cyanide in Percent
Effluent Reduction
(mgfl.)
0.35 46
ND >99.9
0.5 99
0.5 99
ND >99.9
0.5 23
15 70
4.95 55
ND >99.9
0.45 55
0.6 95
Notes: ND = Not detected
Table C-4. Phenol Removals
Phenol
(mg/L)
11
11
11
11
11
12
Hydrogen Peroxide (mg/L)
0
0
60
60
60
60
UV Output
0.36 kW
5kW
5 kW (no cavitation)
5kW
cavitation only
0.36 kW
Percent Reduction
18.2
32
77
95.5
9
87
Table C-5. Combined Cyanide /Phenol Removals
Cyanide
(mg/L)
10
10
13.5
20
Phenol (mg/L) Hydrogen UV Output
Peroxide (mg/L)
12
10
12
20
0 0.36 kW
60 0.36kW + 5kW
60 0.36 kW
0 2.5 kW
Percent
Reduction
50
ND
70
97
Notes:
ND = Not detected
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Equipment
Table C-6. Salmonella Study Results
The tests were conducted using a CAV-OX* I low-energy
pilot-scale unit in parallel with a CAV-OX* II high-energy pilot-
scale unit. The CAV-OX* I low-energy unit consisted of a 2-
horsepower centrifugal pump, a cavitation chamber, a recycle
loop, a low-energy UV reactor with six 60-watt lamps, and a
control panel with the necessary electronics, UV ballasts,
switches, indicator lamps, and circuit breakers. The CAV-OX*
II high-energy unit used the same pump, cavitation chamber,
recycle loop, and control equipment. It also included an
independent power supply and a 5-foot UV reactor with a 2.5-
or 5-kW lamp.
Methodology
Several strains of Salmonella were grown at 35 °C for 24
hours on Standard Methods agar and harvested using a sterile
Butterfield's buffer. Each strain was then held at 4 °C for 1
hour and inoculated into a purged and rinsed 5 5-gallon drum
filled with city water. The initial concentration was adjusted to
obtain a final concentration in the drum of about 1 million cfu/
mL. The influent was also injected with 220 mL of 10 percent
sodium thiosulfate. An electric mixer thoroughly homogenized
the mixture in the drum. A flow rate of 1 gpm was used.
Next, the inoculated water was injected with 80 mg/L
hydrogen peroxide and processed through the CAV-OX* units.
Seven samples were collected as shown in Table C-6.
All Salmonella enumeration was performed using Hektoen
Enteric agar. A 0.45-micron Millipore filter was used for all
filtration analysis. Serial 10-fold dilutions were carried out to
six orders of magnitude (106) using sterile Butterfield's buffer
dilution blanks.
Results
Salmonella concentration was cumulatively reduced a total
of eight orders of magnitude by the CAV-OX* process. Table
C-6 lists the results of this study.
CASE STUDY C-8: Southern California Edison, Los
Angeles, California
Introduction
Southern California Edison, a major U.S. utility company,
contracted with Magnum to conduct a treatability study using
the CAV-OX* process to treat 3 million gallons of seawater
contaminated with fluorescent dyes, lubricating oil, and detergent
Sample Location Concentration
No. (CFU/mL)
1
2
3
4
5
6
7
Untreated water from the 55-gallon
drum
Water exiting the cavitation chamber
at 1 gpm
Water exiting the high-energy, 5-kW
reactor
Hydrogen peroxide-treated water from
the 55-gallon drum
Hydrogen peroxide-treated water
exiting the cavitation chamber
Hydrogen peroxide-treated water
exiting the CAV-OX9 1 UV reactor
Hydrogen peroxide-treated water
exiting the CAV-OX* 11 UV reactor
2,000,000
1,600,000
0.8
3,000,000
1,900,000
500
0.01
emulsions. The water consisted of reverse osmosis reject water
and hydrotest discharge water that was methylene blue-reactive,
indicating the presence of detergent compounds. The water also
contained oxidized iron, which caused scaling at the liquid
surface.
Southern California Edison preferred not to use UV radiation
or hydrogen peroxide injection, since these were considered
treatment systems under existing regulations. Transferring the
water with a pump through a cavitation chamber was not
considered a treatment process.
Equipment
The seawater was fed into a high-volume cavitation chamber
using a 2-horsepower centrifugal pump.
Methodology
The centrifugal pump transferred the process seawater into
the cavitation chamber at 65 psi. The cavitation chamber vacuum
was maintained at 27 inches of mercury, and effluent line
pressure at 6 psi. The flow rate varied between 2 and 4 gpm.
A 15-to-1 ratio was recycled to the cavitation chamber for further
treatment. Discharge from the cavitation chamber flowed to a
holding tank. Samples were collected from the holding tank
and sent to a laboratory for analysis.
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Results
Treatment in the cavitation chamber reduced BOD in
effluent samples by 83.3 to 88.4 percent. The average cost to
treat 1,000 gallons of seawater was $0.13.
CASE STUD Y C-9: Corporation Mexicana de Investigation
en Materials, S.A. de C.V. (CMIMSA)
Introduction
In the spring of 1993, CMIMSA contacted Magnum about
process effluents from a pharmaceutical plant and a petroleum
plant. Magnum conducted a pilot-scale study of the
pharmaceutical plant effluent.
Equipment
Six different process lines generated the pharmaceutical
plant effluent. To accomplish the desired contaminant reduction,
Magnum modified and increased the efficiency of the CAV-OX*
II process. Two changes were made to the equipment design
used for the SITE demonstration:
1. UV window ports allowed UV output to be monitored
with an optical monitor 31 inches from the top of the reactor
2. Engineering modifications substantially improved the
UV lamp efficiency
Methodology
Phenol was selected as a test contaminant. Phenol is an
excellent test chemical for advanced oxidation systems since it
is stable, difficult to break down, and accurate phenol test kits
are readily available.
Results
Table C-7 shows the results of the pilot-scale study. Data
from previous pilot studies (Case Study C-6) are also shown for
comparison. For both studies, influent contained 20 ug/L phenol,
and the process was operated with the addition of 60 mg/L
hydrogen peroxide.
Based on these and other results, the CAV-OX* IIA
modifications increase the reduction efficiency two to four times.
The CAV-OX* IIA modifications allow the measurement and
comparison of UV flux over different operating protocols.
Table C-7. Phenol Removal Comparison
Test No. Flow (gpm) Percent Method
Reduction
CAV-OX* II (Case Study C-6)
1
2
3
4
1
2
4
6
95
55
45
39
Protocol A
Protocol B
Protocol C
Protocol D
CAV-OX® IIA (Modified CAV-OX* Process, Case Study C-9)
1 2 100 Protocol B
2 4 99 Protocol C
3 6 96 Protocol D
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