EPA/832-R-95-005
September, 1995
Emerging Technology Assessment: Preliminary
Status of Airplane Deicing Fluid Recovery Systems
U.S. Environmental Protection Agency
Office of Wastewater Management
Municipal Support Division
Municipal Technology Branch
Washington, D. C.
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NOTICE
This document has been reviewed in accordance with the U.S. .
Environmental Protection Agency's peer review and administration
review policies and approved for publication.
The material presented is for informational purposes only. This
information should not be used without first obtaining competent
advice with respect to its suitability to any general or specific
application. References made in this document to any specific
method, product or process does not constitute or imply an
endorsement, recommendation or warranty by the U.S. Environmental
Protection Agency.
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TABLE OF CONTENTS
PAGE
EXECUTIVE SUMMARY ES-1
SECTION 1 - INTRODUCTION TO AIRPLANE DEICING
FLUID RECOVERY SYSTEMS
Background 1-1
Environmental Effects of Airplane Deicing Fluids 1-3
Environmental Regulation of Ethylene Glycol 1-7
Requirements and Standards for the Reuse of ADF 1-8
Objectives 1-8
SECTION 2 - DESCRIPTION OF COMMERCIALLY AVAILABLE ADF
RECOVERY PROCESSES
Description of Commercially Available ADF Recovery Process 2-1
Chemicals Required 2-4
Design Criteria 2-4
End-Use Specifications 2-5
SECTION 3 - TECHNOLOGY ASSESSMENT
ADF Collection 3-1
Performance Data 3-2
Operation & Maintenance .' 3-2
Technology Costs 3-4
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TABLE OF CONTENTS
PAGE
SECTION 4 - ENVIRONMENTAL IMPACTS
Distillation 4-1
Residuals Generated 4-1
SECTION 5 - SUMMARY OF FINDINGS
•
Applications 5-1
Limitations 5-1
SECTION 6 - REFERENCES 6-1
APPENDIX A - CASE STUDY AND EVALUATION
Deicing System Incorporated A-l
Canadian Chemical Reclaiming LTD (CCR) .... A-l
Glycol Specialists, Inc. (GSI) A-10
ATTACHMENT B - ADF RECOVERY CHECKLIST B-l
LIST OF FIGURES
Figure 2-1 General Glycol Recovery Process 2-3
Figure A-l Deicing Systems' ADR Recovery Process A-3
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TABLE OF CONTENTS
PAGE
Table 1 . 1
Table 3 . 1
Table A.I
Table A. 2
LIST OF TABLES
Mammalian Toxicity Data For Ethylene Glycol and
Propylene Glycol
ADF Recovery System Performance Data Summary
Airplane Deicing Fluid Recovery System
Performance Data from Munich Airport, Germany
Airplane Deicing Fluid Recovery System
Performance Data from Toronto Airport, Canada
1-5
3-3
A-5
A-9
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ACKNOWLEDGMENTS
This manual is the product of the efforts of many individuals. Gratitude goes to each person
involved in the preparation and review of the document.
Contributors
Ms. Lauren Fillmore and Ms. Janet Dell
Peer Reviewers
The following individuals peer reviewed this report:
•
Mr. George Legarreta, Federal Aviation Administration, Design and Operations
Division, Washington, D.C.
Mr. Alan Hais, U.S. EPA, Office of Science and Technology, Washington, D.C.
Technical Direction and Coordination
Mr. Joseph T. Mauro, U.S. EPA, Office of Wastewater Management, Municipal Support
Division, Municipal Technology Branch (4204), 401 M Street SW, Washington, D.C. 20460,
coordinated the preparation of this manual and provided technical direction throughout its
development.
IV
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Executive Summary
EXECUTIVE SUMMARY
PRELIMINARY STATUS OF AIRPLANE DEICING FLUID RECOVERY SYSTEMS
BACKGROUND
Section 402 of the Clean Water Act requires the U.S. Environmental Protection
Agency (EPA) to establish permit requirements under the National Pollutant Discharge
Elimination System (NPDES) for storm water discharges from industrial activity including
airport operations. As airport management has applied for storm water permits, the control of
the release of airplane deicing fluid (ADF) into the environment has become of interest to
airlines, airport management, air safety specialists and Federal, state and local environmental
protection agencies.
This document presents the results of a preliminary technical evaluation of
commercially available ADF recovery processes. This report explores design-related questions,
identifying weaknesses or limitations, provide cost data and are beneficial in the investigation
of operation and maintenance (O&M) problems. In addition, the results of the preliminary
evaluation identifies a specific range of conditions under which the process or technology
demonstrates levels of performance efficiency. This preliminary technology evaluation is an
.essential first step in disseminating actual data on selected processes or techniques. This report
is not intended to establish ADF recovery systems as the preferred approach nor preclude other
systems or methods for the control of ADF or ADF contaminated storm water
ES-l
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Executive Summary
OBJECTIVES
The primary objective of this report is to evaluate the technologies that are currently
being used to recover used ADF. On-site ADF recovery is a new application of proven
technologies: filtration, ion exchange, distillation, and sometimes reverse osmosis. At this time,
ADF recovery technology has had limited application. There is only one on-site application of
ADF recovery in the United States; therefore, this report has only limited data on costs, and
operations and maintenance. The associated cost and performance data discussed in this report
was provided by firms marketing on site ADF recovery systems hi North America. Before using
an ADF recovery system, it is advisable that more data be obtained as it becomes available from
onsite installations within the United States. Accordingly, along with ADF recovery systems,
other system, technologies or methods should be investigated before selecting a final approach
for the control of ADF or ADF contaminated storm water. The specific ADF recovery
processes that are currently being marketed are described in detail.
FINDINGS AND CONCLUSIONS
ADF recovery systems are based on a series of proven processes including primary
filtration, ion exchange or nanofiltration, distillation, and reverse osmosis. The purpose of
primary filtration is to remove suspended solids entrained in the ADF. Ion exchange may be
employed to remove dissolved solids and nanofiltration may be employed to remove polymeric
additives which were in the glycol-based ADF- to meet deicing/anti-icing performance
requirements. Expensive preconcentration steps such as reverse osmosis may be employed to
concentrate dilute streams (<15% glycol) in advance of the distillation process. The key
process step in the overall ADF recovery system is distillation. Distillation is capable of
separating glycol from water with little degradation. Product with high purity (>90%) can be
obtained by two stage distillation provided that the process economics are not prohibitive. The
product may be sold to chemical manufacturers for use in other glycol based products, such as
automotive anti-freeze, synthetics or reused as ADF. Before reuse as ADF, the product must
receive certification for compliance with the Society of Automotive Engineers (SAE)
ES-2
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Executive Summary
performance based standards.
Recovery of collected ADF may be cost effective when the glycol concentration is
15% or greater. At higher concentrations processes such as reverse osmosis may not be
required hi advance of the distillation process. However, storm water permit requirements of
individual airports may require the collection and recovery of lower concentrations of waste
glycol solutions due to the oxygen demanding environmental effects of glycol. One method to
satisfy such a requirement is to add a preconcentration step such as reverse osmosis to an ADF
recovery system. This additional step may add considerably to the capital and operating cost
of an ADF recovery system. Centralized deicing on a dedicated collection pad is another
•>
method for obtaining spent ADF which exceeds the minimum glycol content. Centralized
deicing systems may be impractical for all but the largest airport operations due to the associated
capital and operation cost, and physical size of the system. However, for established airports,
a switch to a centralized deicing system may present operational and logistical problems.
Another significant limitation of this technology is that a mixture of ethylene and
propylene glycols cannot be recovered and separated efficiently hi a single batch process because
the glycols will not separate easily in the distillation process. A recovered mixture consisting
of ethylene and propylene glycol has little commercial value.
Non-uniform application of glycols may result in the ADF recovery system being cost
prohibitive, because of the requirements for two systems and segregated application/recovery
areas. Uniform application of either glycol at one time may allow for a single recovery system
to be utilized by adjusting the distillation temperature. ADF recovery process performance is
uniformly good. However, individual airport-specific conditions and economic considerations
will determine the suitability of ADF recovery at any airport, not technology-based issues or
process performance.
Additional research is recommended as data becomes available from the operation of
ES-3
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Executive Summary
facilities proposed for the St. Lxnris Airport, The new and expanded Denver International Airport
and other airports not discussed in this report that are currently installing recovery processes.
Additional research is also recommended for studying the effectiveness of alternative collection
systems such as vacuum trucks and roller sponges.
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
SECTION 1
INTRODUCTION TO AIRPLANE DEICING FLUID RECOVERY SYSTEMS
BACKGROUND
The employment of chemical^ deicers is recognized by the FAA as an effective safety
procedure hi airborne transportation. However, a result of these airplane deicing/anti-icing
operations is that portions of the chemicals from the chemical deicers will ultimately enter the
storm water system of the airport. This report considers management practices which will
enable airport tenants to continue their deicing practices without compromise while
implementing changes to minimize the discharge of deicing chemicals to surface or
ground water.
The most common aircraft deicing chemicals currently approved by the FAA are
ethylene glycol and propylene glycol. The environmental impact of deicers in airport storm
water runoff has been investigated over the last 5 years (Sills and Blakeslee, 1992). Since EPA
established NPDES permit application regulations for storm water discharges from airports
(Federal Register, 1990), airport management and operations have directed ADF recovery from
research oriented efforts to practical applications of available technologies. EPA and
authorized NPDES States have, or are in the process of writing permits for point source
discharges from airports, including discharges containing deicing fluids. Of particular note is
a general permit EPA intends to issue, which specifically addresses deicing chemical
management (Federal Register, 1993).
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
The data collected by Sills and Blakeslee show the following usages of glycol hi airport
operations:
Application Glycol Used
*•
Annual U.S. ADF Usage 11,500,000 gal/yr (McGreevey, 1990; Roberts, 1990)
Annual Detroit Met Airport 780,000 gal/yr (Morse, 1990; McGreevey, 1990;
Roberts, 1990)
Large Commercial Aircraft 500-1000 gal/plane/flight (Comstock, 1990)
The amount of deicer required to adequately deice a plane is highly dependent on
applicator variability, plane size and the weather conditions. Several airport operators reported
(AAAE Conference on Aircraft Deicing, August 23, 1993) that the annual volume of ADF
employed by the U.S. airlines has increased three fold since the airplane accident at La Guardia
Airport in 1992 in which icing was a factor. As implied by this statement by employing a
factor of three to the data reported above, nearly 35 million gallons of ADF may be used
annually in the U.S. Depending on specific site and variable weather conditions, the actual
amount of ADF used annually can vary. Since safety concerns are paramount in air travel,
minimization of the volumes of ADF employed are not recommended. However, collection
and recovery of the chemicals must be considered.
There are two types of ADF formulations: Type I and Type II. Both formulations are
deicers and anti-icers which remove ice and remain on the aircraft to prevent subsequent
reicing. Both Type I and Type II formulations are glycol-based but have different additives
and different glycol concentrations. Type I fluids have rust and precious metal corrosion
1-2
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
inhibitors, surfactants, and wetting agents. In addition, Type II fluids contain thickening
agents, usually polymers, which provide improved anti-icing properties and longer holdover
times than Type I fluids.
Typically, Type I fluids are relatively easy to process and recover the glycol present
in the fluids. Type II fluids pose more of a challenge as they contain numerous complex
polymers that are used to create some of the special characteristics in Type II fluids. These
complex polymers present in Type II fluids pose unique handling problems for filtering and
processing systems.
Of the Type I deicing solution applied to aircraft, almost half will fall to the apron
(Transport Canada, State of the Art Report on Aircraft Deicing/anti-icing, AK 75-09-129,
November, 1985). Approximately 35 percent of the ADF is dispersed to the air and the
remainder is retained on the aircraft. The diluted product that is applied to aircraft typically
contains about 58 percent glycols which gives the minimum freezing point of -56.7 °F (FAA,
AC150/5320-15, 1991). Unless it is captured for recycling, recovery or treatment, this glycol-
laden solution flows away to be further diluted and possibly mixed with runway runoff, parking
lot runoff, and other local sources of storm water. This data coupled with a possible annual
usage of 35 million gallons, suggest that if the storm water runoff from aircraft deicing
operations are not adequately treated or contained, substantial amounts of deicing chemicals
may be released to the ground, and may ultimately contaminate ground *or surface waters.
The biodegradation of glycols released into the aquatic environment, which is variable
relative to temperature, can be rapid and extremely oxygen demanding. Glycol contaminated
storm water runoff can deplete dissolved oxygen levels and threaten oxygen-dependent aquatic
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
life in receiving waters. The BOD5 at 20° C for ethylene glycol has been reported to be in the
range of 400,000 to 800,000 mg O2/l (FAA, AC150/5320-15, 1991), or 0.4 to 0.7 g/g
(Verschueren, 1983). The BOD5 of-propylene glycol is considerably higher (about 1 g/g).
Diluted ethylene glycol in storm water runoff, at concentrations qf 1 percent to 0.1 percent,
would be expected to exert a BOD5 of roughly 5,000 to 500 mg/1. Based upon physical
properties, neither ethylene nor propylene glycol released into the environment is expected to
*
be retained in the tissue of organisms and increase with continued exposure (bidaccumulate).
Human Health Effects *
Ethylene glycol exhibits relatively low acute and chronic toxicity to humans and
laboratory animals. It has not been found to cause cancer or mutations; however, it is a
teratogen. The life time drinking water health advisory for ethylene glycol is 7 mg/1 and the
one day health advisory is 18.86 mg/1 (Health Advisory, 1987). Mammalian toxicity data for
both ethylene glycol and propylene glycol is presented in Table 1.1. The mammalian toxicity
data indicates that propylene glycol is less toxic than ethylene glycol.
ADF mixtures contain various types of additives in addition to glycols which constitute
the primary component. These additives include precious metal corrosion inhibitors, rust
inhibitors, thickening agents, and surfactants. The following contaminants may also be present
in glycol-based ADF: diethylene glycol, ethylene oxide, dioxane, and acetaldehyde (trace levels
only). Dioxane and acetaldehyde are suspected carcinogens or teratogens.
Environmental Health Effects
High concentrations of glycols (greater than 10,000 mg/1) are required to cause acute
aquatic toxicological effects (Hartwell, et. al. 1993) Although the ethylene and propylene
1-4
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
TABLE 1.1
MAMMALIAN TOXICITY DATA FOR
ETHYLENE GLYCOL AND PROPYLENE GLYCOL(1)
Dose ml/kg
Toxicity Test
Rat:
Guinea pig:
Mouse:
Rabbit:
Dog:
Human:
single oral LD50(2)
single oral LD50
single oral LD5()
single oral LD50
single oral LD50
single lethal oral
Ethylene
Glycol
5.50
7.35
13.1
—
—
1.4
Propylene
Glycol
32.5
18.5
9.6
(1) From Verschueren (1983).
(2) is the lethal dose for 50% of the exposed organisms.
1-5
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
glycols in ADF have a low potential to exhibit aquatic toxicity, the contaminants and additives
in ADF pose a greater concern when released into the environment. Corrosion and rust
inhibitors are highly reactive which translates into high biological toxicity. Surfactants are also
very toxic to aquatic organisms (Hartwell et. al. 1993).
The Maryland Department of Natural Resources (Hartwell et. al. 1993) conducted
e
aquatic toxicity testing with both ethylene glycol deicer solution and propyfene anti-icer
solution. Test results indicated that the ADF solutions were more toxic than the literature
values for pure glycol substances. The higher toxicity was concluded to be due to the presence
of additives. The specific additives in the Type II fluid were significantly more toxic than the
Type I fluids. Type I deicer exhibited acute toxicity to fish at 8.75 ml/L or a 0.87% solution.
Type II deicer exhibited acute toxicity at 0.063 ml/L. Measurements of ADF concentrations
in Baltimore Washington International Airport storm runoff detected peak concentrations of
Type I ADF at 89.1 ml/L arid of Type II ADF at 154.5 ml/L (Lubbers, 1993).
Similar studies conducted at Stapleton Airport, Denver, Colorado, confirmed that ADF
formulations exhibited significantly more acute toxicity than pure glycol products (ENSR
Consulting and Engineering, 1993). In chronic studies, ENSR found that the concentration that
inhibits growth and reproduction in 25% of the exposed organisms (IC25) of formulated
propylene glycol ADF was 112 mg/L for fathead minnows; while the IQs for pure propylene
glycol was observed to be 6.,941 mg/L.
Data concerning the toxic potential of storm water runoff containing ADF at airport is
preliminary and subject to an ongoing debate. Initial peer review comments of the data
provided by the two studies, has raised several concerns that need to be addressed. To address
these concerns, duplicate testing and additional studies, with peer review, are needed before
confirming the toxicity of storm water runoff containing ADF.
1-6
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
ENVIRONMENTAL REGULATION OF ETHYLENE GLYCOL
Under the 1990 Amendments to the Clean Air Act, national emission standards were
established for hazardous air pollutants from stationary sources. Congress established a list
of 189 hazardous air pollutants. Ethylene glycol is included on this list, however, propylene
glycol is not.
Under the Comprehensive Environmental Response, Compensation and Liability Act
(CERCLA), if a substance is regulated under other legislation, such as the Clean Air Act, it
is included by reference as a CERCLA (Superfund) hazardous substance. As such, ethylene
glycol is a CERCLA hazardous substance while propylene glycol is not. All CERCLA
hazardous substances without specific promulgated reportable release quantities fall under the
statutory reportable amount of one pound. The reporting limits on ethylene glycol has been
raised to 5000 pounds, effective July 12, 1995 (Federal Register, 1995). Therefore, there is
a requirement to report all releases to the environment of ethylene glycol that exceed 5000
pounds unless the release is covered by other environmental protection programs, such as the
storm water NPDES permit program. This necessitates reporting requirements for releases of
ethylene glycol, in amounts that exceed 5000 pounds, to the air or to the ground as part of land
disposal practices or accidental spills.
Neither ethylene glycol nor propylene glycol are hazardous wastes under Resource
Conservation and Recovery Act (RCRA). Contaminants in ethylene or propylene glycol,
particularly metals, may make still certain bottoms or residues from ADF recovery a hazardous
waste if the waste fails the toxicity characteristic limits for metals.
1-7
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Section 1 - Introduction to
Airplane Deicing Fluid Recovery Systems
REQUIREMENTS AND STANDARDS FOR THE REUSE OF ADF
The Society of Automotive Engineers (SAE) develops standards for deicing and anti-
icing fluids for aircraft and runways. Both Type I and Type II ADF have performance
requirements identified in AMS 1424 and AMS 1428. Because of the interest in the recovery
of ADF, SAE issued a policy statement that recycled fluids be certified to original
f
specifications (Committee J, SAE, 1993). Consequently, recycled fluids must meet the same
requirements as virgin glycol. Certification that ADF meets the appropriate standards (AMS
1424 or AMS 1428) is provided by^the chemical industry. All recovered ADF used in the
U.S. must be certified prior to reuse in the airline industry. Certification of recovered ADF
fluid at on-site recovery systems is impractical due to performance testing requirements.
Unless the industrial practices are changed to an ADF composition basis, it is unlikely the
recovered ADF fluid will be recycled directly to aircraft at the airport. In regards to runway
deicers, FAA requires certifications to AMS 1426.
OBJECTIVES
The goal of this study was to evaluate technologies that could be used to recover spent
aircraft deicing fluid for reuse in aircraft deicing, runway deicing or other applications. This
study had the following critical objectives:
Evaluate the effectiveness of commercially available recycling units in
generating products that may be reused.
Evaluate the waste reduction potential.
1-8
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Section 2 - Description of
Commercially Available ADF Recovery Processes
SECTION 2
DESCRIPTION OF COMMERCIALLY AVAILABLE ADF RECOVERY PROCESSES
There are three companies which are currently marketing ADF recovery systems for
use on-site at airports in North America. Each of the three processes is briefly described in the
following subsections. A complete description of each process is provided in Section 6. At this
time, there is only one on-site application of ADF recovery in the United States. This is a pilot-
scale operation located at Continental Airlines at the Denver Stapleton Airport. The operation
is designed and run by a cooperative effort of Gylcol Specialists, Inc. and Zenon Environmental,
Inc.
The technology of ethylene or propylene glycol recovery by primary filtration, ion
exchange or nanofiltration, and distillation has been proven in other industries where glycol
recovery is utilized, such as the petroleum industry. Chemical waste service companies have
provided offsite treatment of ethylene glycol for the automotive and gas processing industries.
Each of the glycol recovery systems is comprised of the three process units:
Primary Filtration: To remove suspended solids entrained in the ADF from contact
with the aircraft and asphalt. Suspended solids must be removed to avoid plugging of
downstream processes and spray machinery.
Ion-Exchange: To remove dissolved solids such as chlorides and sulfates.
and/or
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Section 2 - Description of
Commercially Available ADF Recovery Processes
Nanofiltration: To remove polymeric ADF additives such as corrosion inhibitors,
surfactants, and wetting agents.
Distillation: To remove water which has contaminated the ADF due to ice melt and
storm water dilution.
Figure 2-1 presents a schematic of the general glycol recovery process.
*
*
The key process step in the overall ADF recycling system is distillation. Distillation
is defined as the separation of more volatile materials (in this case, water) from less volatile
materials (glycol) be a process of vaporization and condensation. Distillation has been used for
many years for purification in chemical manufacturing and in processes involving internal
solvent recycling (Freeman, 1989). Distillation is capable of recovering volatile species with
little degradation, which is an important advantage in this application where the recovered
product can be sold or recycled: Product purity of any desired level can theoretically be
obtained by distillation, however the cost to the process can become prohibitively expensive.
In the separation of water from the glycol mixture of ADF, two stages of distillation are
employed to remove enough water to produce a minimum 50% glycol content in the recovered
ADF. The recovered glycol is a stable material and can theoretically be stored for an entire wet
weather season (6 months).
The details of the distillation process that each vendor employs are proprietary.
Design variables include temperature, distillation column design (number of stages, type of
packing, size) and reflux ratio (ratio of their cycle flowrate to the overhead product flowrate).
Batch distillation systems are employed due to the variation in the composition of the influent
and the irregular supply of the feed. Reverse osmosis may also be employed to concentrate very
dilute glycol (< 15%) prior to the distillation step.
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Section 2 - Description of
Commercially Available ADF Recovery Processes
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Section 2 - Description of
Commercially Available ADF Recovery Processes
CHEMICALS REQUIRED
Sodium hydroxide (NaOH) and hydrochloric acid (HC1) are required for regeneration
of the ion exchange process unit. Anti-foam agents are required in the distillation tower. Care
should be taken when handling these chemicals to avoid contact with skin. Eye protection
should be worn.
DESIGN CRITERIA
Prior to designing an ADF recovery system, information on several parameters must be
i
collected. Data in the following areas is required to design an ADF recovery system:
Deicing Fluid Data
Type
Concentration
Total consumption per season
Total consumption per peak-day
Average consumption per aircraft
Airport Operations Data
Length of deicing season
Number of deicing days per season
Future traffic extension plans
Spent Fluid Data
Volume Generated
Glycol Concentration
Contaminants
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Section 2 - Description of
Commercially Available ADF Recovery Processes
Reuser Specifications
Glycol Concentration
Acceptable Impurities.
END-USE SPECIFICATIONS
•
In Europe, recovered ADF can be reused at the same airport location as the recovery
operations. Therefore, the glycol content in recovered Type I ADF is targeted to the 58%
glycol content for direct use on aircraft after the addition of any necessary additives. In the
U.S. and Canada, the recovered glycol must be returned to the chemical industry for
performance-based testing and reformulation into ADF. The end-use specification in North
America, therefore, is for higher glycol content in order to have a reusable end-product.
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Section 3 - Technology Assessment
SECTION 3
TECHNOLOGY ASSESSMENT
ADF COLLECTION
In order for the spent ADF to be recovered or regenerated, it must first be collected at
•
the airport. The implementation of ADF7 collection must respond to the unique requirements of
each airport. The feasibility of recovery glycol is dependent on the ability of the collection
system to contain a relatively concentrated waste stream without significant contamination by
other storm water components. It may not be cost-effective to distill and recycle waste glycol
solutions at low concentrations (< 15%), because additional expensive processes, such as
reverse osmosis, may be needed to concentrate the solutions to a lower concentration before the
distillation step. However, storm water NPDES permit requirements of individual airports may
require the collection and recovery of lower concentrations of waste glycol solutions due to the
oxygen demanding environmental effects of glycols in general.
Remote or centralized deicing with the containment and collection of used glycol is one
method for collecting concentrated used glycol. However, centralized deicing systems may be
impractical for all but the largest airport operations due to the cost and physical size. For
established airports, a switch to centralized deicing systems would present a number of
operational and logistical problems. In lieu of a centralized facility, used glycol can be collected
via vacuum trucks and fluid collections containers to siphon glycol from runway aprons.
Employment of vacuum trucks has shown good results. Roller sponge devices were employed
at the Toronto Airport with mixed results due to uneven frozen surfaces.
At Denver's Stapleton Airport a centralized collection facility consisting of a sloped pad,
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Section 3 - Technology Assessment
underground storage tank (UST), storm water diversion and piping and pumps is employed by
Continental Airlines to collect ADF. The system reportedly captures the used glycol solution
at 25 to 40 percent glycol concentration.
A centralized system is proposed for the St. Louis Lambert Airport. A pad has been
proposed by Findett Engineering that will be capable of holding more than one narrow body
airplane at one time. The fluid is collected from the pad and held hi a storage tank for
processing. A skid mounted processing unit will reportedly treat the ADF when the system is
•
started up.
i
PERFORMANCE DATA
Performance data was provided by three firms, Deicing System, Canadian Chemical
Recovery (CCR), and Glycol Specialists. Data supplied by Deicing System was from their full-
scale operation in Munich, Germany and by Glycol Specialists from their recovery system at
Continental Airlines at Stapleton Airport. Performance data was provided by CCR from the
pilot recovery system at the Toronto Airport. The ADF streams prior to recovery had an
average glycol content between 10 to 28%. The recovery systems produced an effluent stream
with an average glycol content of between 55.1 and 98.5 %. The glycol content of the recovered
solution was dictated by the needs of the reuser and does not reflect performance limitations.
Table 3-1 shows the average performance data for these three systems.
OPERATION & MAINTENANCE
Recovery processes based on distillation tends to be complex operations due to the
inherent thermodynamic constraints. Distillation-based processes have a number of practical
limitations on usefulness. Distillation is a batch operation. Batch operation, because of its
cyclic nature, involves frequent start-ups and shutdowns and must be operated by highly skilled
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Section 3 - Technology Assessment
TABLE 3.1
ADF RECOVERY SYSTEM PERFORMANCE DATA SUMMARY
Process
Average
Influent
Glycol
Location Content (%)
Average Minimum
Effluent Glycol
Glycol Specification
Content (%) by End-User (%)
Deicing System, Inc. Munich 18.6
Canadian Chemical Recovery Toronto 10-20
Glycol Specialists, Inc. Denver 28
55.1
87
98.5
50
80
90-95
Notes:
1. Data supplied by Deicing Systems, Inc., Canadian Chemical Recovery;
Glycol Specialist, Inc.
2. Concentrations measured in laboratory.
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Section 3 - Technology Assessment
personnel. Second, distillation equipment is expensive, and capital recovery charges usually
constitute the major portion of the product recovery costs. Third, recovery by distillation is
energy-intensive, with nominal energy requirements being about S.SlxlO5 to 2.79xl08 J/kg of
feed (250 to 1200 BTU/lb of feed).
TECHNOLOGY COSTS
ADF recovery is a new application of existing technology. Due to the limited full-scale
. • »
operation of ADF systems in the country, information on technology costs are limited. Cost
estimates discussed here have been provided by GSI. Based on pilot studies performed at the
Denver Stapleton Airport, The total capital cost for the complete project, including deicing/anti-
icing application equipment, collection piping, storage facilities, and the glycol recovery system
has been estimated to be between six and seven million dollars. The construction cost for the
ADF collection system, storage and handling facilities, piping and recovery system has been
estimated at approximately $600,00.
The total capital cost for the new Denver International Airport, including deicing/anti-
icing application pads and equipment, drainage and collection piping, storage and handling
facilities, and a complete glycol recovery system is currently estimated to be between 20 to 25
million dollars. These costs are based on a complete package including planning, engineering
design, equipment, construction and installation, start-up services and other contingencies. The
construction costs for the ADF collection system, storage and handling facilities, piping, controls
and instrumentation, and a complete recovery system is currently estimated at five million
dollars.
The GSI cost for recovering collected ADF, assuming the used ADF is 28%
glycol, is approximately 35C/gallon. The greatest annual cost with the ADF recovery system
is the cost for the energy used in the distillation process.
-------
Section 4 - Environmental Impacts
As discussed in Section 1, up to 35 million gallons of ADF may be used in a single year,
depending upon variable weather conditions. Based upon this estimate, the percentage of glycol
typically found in ADF and the percentage of ADF that falls to the pavement during application,
as much as 75 million pounds of glycol can be released into the environment in a single year.
Insignificant amounts of Type II glycol is released to the runway when the airplane takes off.
The capture and reuse of ADF that occurs as the result of ADF recovery operations will reduce
the amount that is either released into the environment or captured for disposal.
DISTILLATION
There is a potential for volatile-organic emissions to the air from the distillation process
through losses from condenser vents, accumulator tank vents, and storage tank vents. Since the
amount of glycol which is vaporized during normal operations is small, VOC emissions to the
air are likely to be insignificant.
RESIDUALS GENERATED
Ion-exchange flush and spent regenerant are generated by the recovery process and may
be disposed of, if permitted, after neutralization by the addition of acids or bases, to the sanitary
sewer. Spent filter cartridges, containing dirt, oil and other solids, may be disposed of as non-
hazardous waste. Only insignificant traces of glycol will be retained in the filtration solids.
Under CERCLA, Section 103, any wastes containing over 5000 pounds of ethylene glycol have
additional reporting requirements. As of July 12, 1995, the reporting limit on ethylene glycol
was adjusted from one pound to 5000 pounds (Federal Register, 1995). Any release of ethylene
4-1
-------
Section 4 - Environmental Impacts
glycol to the air or ground, as part of land disposal practices or accidental spills, will have
additional reporting requirements. Propylene glycol, alone as a waste, does not have any
reporting requirements under CERCLA. However, local authorities should be contacted to
determine if any requirements have to be met for the disposal of spent filter cartridges containing
propylene glycol. Distillation condensate, with less than 1.5% glycol, is also generated and may
be reused in airport operation or (if permitted) disposed of to the sanitary sewer. Local
pretreatment requirements might limit the amount of oxygen demanding wastewater discharged
to a municipal sewer system and wastewater treatment works.
4-2
-------
Section 5 - Summary of Findings
SECTIONS
SUMMARY OF FINDINGS
Although the on-site application of ADF recovery is new ADF recovery technology has
been proven in other industries, such as the automotive industry. Distillation-based ADF
recovery systems are capable of recovering glycol with little degradation and a high product
•
purity. Product purity, typically with a minimum of 50%, is dictated by the end-user; however,
high product purity (over 90%) can be obtained provided the process economics are not
prohibitive.
APPLICATIONS
Glycol recovery systems are applicable at any airport that collects ADF with a minimum
concentration of approximately 15% glycol. Collection and recovery of dilute glycol (< 15%)
is driven by the storm water NPDES permit requirements of individual airports. Since spent
ADF mixtures with lower glycol content are impractical to recover via distillation without
expensive preconcentration steps such as reverse osmosis, dilute streams are typically discharged
to POTWs, subjected to destruction of organics or removed by jchemical waste companies.
Ultimately, the site specific application of on-site ADF recovery will be based on local permit
requirements and economic considerations including spent ADF collection costs, recovery
economics, end-product purity and disposal or treatment costs.
LIMITATIONS
In order for the ADF to be recovered or regenerated, it must first be collected at the
airport. The implementation of ADF collection must respond to the unique requirements of each
airport. The feasibility of recovery glycol is dependent on the ability of the collection system
5-1
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Section 5 - Summary of Findings
to contain a relatively concentrated waste stream without significant contamination be other
storm water components. It may not be cost-effective to distill and recycle waste glycol
solutions at low concentrations « 15%). Remote or centralized deicing with the containment
and collection of used glycol is one method for collecting concentrated used glycol. However,
centralized deicing systems may be impractical for all but the largest airport operations due to
the cost and physical size. For established airports, a switch to centralized deicing systems
would present a number of operational and logistical problems.
*
In lieu of a centralized facility, used glycol can be collected via vacuum trucks and fluid
collections containers to siphon glycol from runway aprons. Roller sponge devices may also be
employed. However, previous experiences with roller sponge devices at the Toronto Airport
have had limited success do to uneven frozen surfaces.
Glycol recovery systems are designed specifically for ethylene or propylene - type deicing
fluids. Mixtures of ethylene and propylene glycols cannot be recovered and separated effectively
in.a single batch process because the glycols will not separate easily hi the distillation systems.
Processing of a mixture of both glycols through a typical two tower distillation-based recovery
system will result in a recovered, concentrated mixture of ethylene and propylene glycol with
little commercial value. A prohibitively expensive and elaborate distillation system would be
required to separate ethylene and propylene glycol from each other'because of the closeness of
their boiling points. Airports which desire to recover their spent ADF must use only one type
of solution or segregate application and runoff areas if both types of solutions are employed.
The SAE performance-based standards for ADF indirectly limit the on-site application of ADF
recovery since all recovered product must be returned to glycol suppliers for performance-based
recertification.
Studies into the effectiveness of these alternative collection systems should be considered
in the future. These studies should also investigate both cost and environmental benefit.
5-2
-------
Section 6 - References
SECTION 6
REFERENCES
American Association of Airport Executives, Conference on Aircraft Deicing, August 23, 1993,
Washington, D.C. .
Comstock, C. 1990. as cited in Sills, R.D. and Blakeslee, P.A., 1992. "The Environmental
Impact of Deicers in Airport Storm Water Runoff", in Chemical Deicers in the
Environment, ed. Frank M. D'ltri, Lewis Publishers, Inc. Chelsea, MI.
ENSR Consulting and Engineering. 1993. Evaluation of the Biotic Communities and Chemistry
of the Water and Sediments in Sand Creek near Stapleton International Airport. Prepared
for Stapleton International Airport. Document No. 6321-002.
Freeman, H.M., 1989. Standard Handbook of Hazardous Waste Treatment and Disposal,
McGraw-Hill, New York, 1989.
Federal Aviation Administration. 1991. Advisory Circular (150/5320-15): Management of
Airport Industrial Waste. U.S. Department of Transportation, Washington, D.C.
Federal Register. November 16, 1990 EPA Administered Permit Programs; the National
Pollutant Discharge Elimination System. Vol. 55, No. 222. page 48062.
(Available - OWRC)
Federal Register. November 19, 1993. Fact Sheet for the Multi-Sector Stormwater General
Permit (Proposed). Vol. 58, No. 222. page 491587. (Available - OWRC)
6-1
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Section 6 - References
Federal Register. June 12, 1995. Hazardous Waste: Reportable Quality Adjustments. Vol.
60, No. 112. pages 30926-30962 (Available - OWRC).
Hartwell, S.I., D.M. Jordahl, E.B. May. 1993. Toxicity of Aircraft Deicer and Anti-icer
Solutions to Aquatic Organisms. Chesapeake Bay Research and Monitoring Division,
\
Annapolis, Maryland. CBRM-TX-93-1.
Health Advisory, 1987. Ethylene Glycol. Office of Drinking Water, U.S. Environmental
Protection Agency. PB87-235578. (Available - NTIS - PB87-235578)
Kaldeway, J. 1993. Director of Airport Operations. L.B. Pearson International Airport,
Toronto, Canada. Personal communications with Lauren Fillmore, Engineering-Science,
Inc.
Legarreta, G. 1993. Civil Engineer, Design and Operations Criteria Division, Federal Aviation
Administration. Personal.communication with Lauren Fillmore, Engineering-Science,
Inc.
Lubbers L. 1993. Laboratory and Field Studies of the Toxicity of Aircraft Deicing Fluids.
Presentation to the SAE Aircraft Ground Deicing Conference, Salt Lake City, Utah, June
15-17, 1993.
McGreevey, T. 1990. as cited in Sills, R.D. and Blakeslee, P.A., 1992. 'The Environmental
Impact of Deicers in Airport Storm Water Runoff", in Chemical Deicers in the
Environment, ed. Frank M. D'ltri, Lewis Publishers, Inc. Chelsea, MI.
Morse, C. 1990. as cited in Sills, R.D. and Blakeslee, P.A., 1992. "The Environmental Impact
of Deicers in Airport Storm Water Runoff", in Chemical Deicers in the Environment, ed.
Frank M. D'ltri, Lewis Publishers, Inc. Chelsea, MI.
NIOSHTIC"1 Search Results - Ethylene Glycol, Propylene Glycol
6-2
-------
Section 6 - References
Roberts, D. 1990. as cited in Sills, R.D. and Blakeslee, P.A., 1992. The Environmental
Impact of Deicers in Airport Storm Water Runoff", in Chemical Deicers in the
Environment, ed. Frank M. D'ltri, Lewis Publishers, Inc. Chelsea, MI.
SAE International. May 17, 1993. Unconfirmed Minutes of Meeting No. 37 of AMS
Committee, Rome, Italy.
Sills, R.D. and Blakeslee, P.A., 1992. "The Environmental Impact of Deicers in Airport Storm
Water Runoff", in Chemical Deicers in the Environment, ed. Frank M. D'ltri, Lewis
Publishers, Inc. Chelsea, MI.
Transport Canada. 1985. State-of-the-Art Report of Aircraft Deicing/Anti-icing. Professional and
Technical Services, Airports and Construction, Airport Facilities Branch, Facilities and
Environment Management. AK-75-09-129. (Type I Fluid Only)
Verschueren, K. 1983. Handbook of Environmental Data on Organic Chemicals. 2nd Edition.
Van Nostrand Reinhold Co., New York, N.Y.
6-3
-------
Section 6 - References
Sources for information for Section 6:
U. S. Dept. of Commerce
National 'fechnical Information Services (NTIS)
5285 Port Royal Road
Springfield, Virginia 22161
Telephone: . (703) 487-4650
(Rush Orders Only) 1-800-553-6847
FAX (703) 321-8547
Education Resources Information Center/Clearinghouse for Science, Mathematics and
Environmental Education (ERIC/CSMEE)
1929 Kenny Road
Columbus, Ohio 43210-1015
Telephone: (614) 292-6717
FAX: (614)292-0263
Office of Water Resource Center (OWRC)
RC4100
401 M Street, SW
Washington, D. C. 20460
Telephone: (202) 260-7786
FAX: (202) 260-4383
-------
Appendix A - Case Studies and Evaluation
APPENDIX A
CASE STUDIES AND EVALUATION
The following section presents specific information on the ADF recovery processes evaluated
for this report. The information is provided in a checklist format.
DEICING SYSTEM INCORPORATED
1. Company Address:
North America Office:
8737 Red Deer Circle
Louisville, Kentucky, 40220
Head Office:
S-951 84 Lulea
Sweden
2. Contact Name: Mr. Bernt Lidstrom
Phone: (502) 499-8609
Fax: (502) 491 7881
3. Current Status of Applications
Deicing System has provided large ADF recovery systems in three locations in Europe:
Location Capacity Start-up Date
Lulea, Sweden 80 gal/hr 1984
Oslo, Norway 530 gal/hr 1989
Munich New Airport, Germany 1,320 gal/hr 1992
A-i
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Appendix A - Case Studies and Evaluation
Process data for the Munich Airport system has been obtained and is presented below.
For the North American market, Deicing System has developed a mobile recovery plant for
deicing aircraft fluid. The mobile recovery plant has the capacity to recover deicing fluid from
one airport or several smaller airports. All processing equipment is contained in a semitrailer,
easily hitched to a truck. Once the mobile recovery plant is positioned, it is connected to the
available energy supply at the airport, and to holding tanks for collected and recovered deicing
fluid. The processing equipment is similar to that of the large plants for fluid recovery that
Deicing System has developed and installed at the airports in Europe.
To date, Deicing System does riot have any North American field applications of their
recovery system.
4. Process Description
The glycol recovery plant employed by Deicing System in Europe consists of a three-
stage process shown in Figure A.I. The recovery process was constructed in a building with
a floor area of 6,000 sq ft and is 30 ft high. The building has a steel framework and has a
cladding of double steel sheeting with an insulation in between the sheetings. The steam-boiler,
control room, electrical distribution and chemical storage are each located in separate rooms.
The first stage of the recovery process is filtration to remove suspended solids, such as
sand, from the fluid. Filters F-01 and F-02 have a mesh width of 50 and 10 microns,
respectively. Duty and standby filters are provided for continuous operation of the process.
The second step of the process is an ion exchange system (DM-01) where positive and
negative ions, e.g. chlorides and sulfates, are removed. The conductivity of the effluent from
A-2
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Appendix A - Case Studies and Evaluation
i
>
I
CD
I
Cfl
O
u
o
A-3
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Appendix A - Case Studies and Evaluation
the ion exchange columns is measured. When it reaches a predetermined value, a regeneration
of the columns is initiated. The columns are regenerated by flushing with water, followed by
NaOH in the first column and HC1 in the second column, and a final flush with water prior to
going back on-line. The flush waters and spent regeneration chemicals are collected in a
neutralization tank prior to discharge to the sanitary sewer.
The effluent from the ion-exchange columns is stored in Tank T-2. From Tank T-2 the
fluid is fed through heat exchanges H-01 and H-05 and then sprayed into distillation tower D-01.
A portion of the water is removed from the fluid in this tower. The fluid is thertr sprayed into
distillation tower D-02 for further removal of water. The concentration of the effluent product
is measured with a densiometer. When the concentration of the fluid has reached the
predetermined value, the fluid is fed to the ready tank T-04.
The water content of the distillation effluent can be guaranteed at a minimum of 50%.
The glycol content in the condensate is guaranteed to not exceed 1.5%.
In Europe, a wetting agent and a corrosion inhibitor must be added to the recovered
product prior to reuse as airplane deicing fluid. The whole process is fully controlled by a
process computer and PLC.
5. Performance Data
Performance data was provided by Deicing System from the recovery system at the
Munich Airport. Table A.I shows that the influent stream had an average glycol content of
18.6%. The recovery system produced an effluent stream with an average glycol content of
55.1%.
A-4
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Appendix A - Case Studies and Evaluation
TABLE A.I
AIRPLANE DEICING FLUID RECOVERY SYSTEM
PERFORMANCE DATA FROM MUNICH AIRPORT, GERMANY
Time
Hours
1
2
3
4
5
6
7
8
9
10
Average
Influent
Glycol
Concentration %
20.4
20.7
20.9
20.9
20.9
20.8
20.4
20.2
11.3
9.8
18.6
Effluent
Glycol
Concentration %
56.5
55.4
55.4
55.4
56.1
55.1
54.6
55.4
54.0
53.0
55.1
Notes:
Data supplied by Deicing Systems Inc.
Concentrations measured in the laboratory.
A-5
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Appendix A - Case Studies and Evaluation
6. Process Reliability
In the data provided for the Munich Airport, the process reliably produced an effluent
with a glycol content over 50%.
7. Maintenance and Energy Requirements
Steam is required by. the recovery system. The system has been designed to employ
excess heat from the distillation columns in other units. In the system shown in Figure A.I,
steam is produced in boiler B-01. The heating media can be oil or gas.
A-6
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Appendix A - Case Studies and Evaluation
CANADIAN CHEMICAL RECLAIMING LTD. (CCR)
1. Company Address:
610 Prairie Meadows Close
Brooks, Alberta, T1R OC9
2. Contact Name:
Mr. Howard Ames
Phone: (403) 362-6229
Fax: (403) 362-6202
3. Current Status of Applications
CCR provided a mobile treatment and recovery system at the L.B. Pearson International
Airport in Toronto, Canada in the winter of 1992. CCR's patented technology was developed
with the assistance of the Canadian National Research Council, Alberta Research Council, and
Environment Canada.
CCR has provided chemical refining services to the gas processing and petrochemical
refining industries for 15 years. Ethylene glycol recovery systems, based on the distillation
process, have been provided by CCR in these industries. CCR is transferring the technology
they have gained in ethylene glycol recovery to ADF recycling.
4. Process Description
At the Toronto Airport, the ADF was collected from the ramp and deicing areas, used
by various carriers, with vacuum or roller sponge devices and delivered to the storage facility
built by CCR. In certain designated areas where significant deicing occurs, a simple
containment system has been used with pump out and temporary storage capabilities. This
A-7
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Appendix A - Case Studies and Evaluation
material is then transferred to the tank farm for processing. When volumes dictate, the collected
fluid is processed by CCR's refining equipment.
The recovery system is a three stage process of filtration, ion exchange, and vacuum
distillation. The unit's production capacity is 1200 Imperial Gallons per hour. The refined
glycol product is resold for reuse in automotive antifreeze. The water condensate is disposed
to the sanitary sewer.
*
*
5. Performance Data
Performance data was provided by CCR from the recovery system at the Toronto
Airport. Table A.2 shows that the influent stream had an average glycol content of between 10
to 20%. The recovery system produced an effluent stream with an average glycol content of
87%.
6. Process Reliability
In the data provided for the Toronto Airport, the process reliably produced an effluent
with a glycol content over 80% as required by the reuser.
7. Maintenance and Energy Requirements
Steam is required by the recovery system. The system has been'designed to employ
excess heat from the distillation columns in other units.
A-8
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• Appendix A - Case Studies and Evaluation
Sample
TABLE A.2
AIRPLANE DEICING FLUID RECOVERY SYSTEM
PERFORMANCE DATA FROM TORONTO AIRPORT, CANADA
Influent
Glycol
Concentration (%)
Effluent
Glycol
Concentration (%)
1
2
3
4
5
Average
Notes:
1.
2.
,10
10
10
10
10
10
-20
-20
-20
-20
-20
-20
89.7
86.1
79.0
90.4
91.5
87.3
Data supplied by Canadian Chemical Reclaiming Ltd.
Concentrations measured in the laboratory.
A-9
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Appendix A - Case Studies and Evaluation
GLYCOL SPECIALISTS, INC. (GSI)
1. Company Address:
5915 North Broadway
Denver, CO 80216
2. Contact Name:
Mr. Jim Hamilton
Phone: (303) 292-2000
Fax: (303) 292-0429 •
3. Current Status of Applications
GSI owns and operates a glycol recovery system in Denver, CO. GSI has accepted and
treated the glycol contaminated runoff from 25% to 35% of the deicing fluid volume generated
at the Denver Stapleton Airport for the last 4 years. The area collected from at the airport is
Continental Airline's terminal. The collected runoff is stored in aboveground tanks adjacent to
the airport property and is transported to the glycol recovery facility. The tanks have a total
capacity of 160,000 gallons. It is estimated that a heavy storm generates between 30,000 to
100,000 gallons of contaminated runoff.
The recovery system is located 5 miles away and operates year round. GSI accepts
glycol contaminated liquids from sources other than the airport. Approximately 450,000 gallons
per season of glycol contaminated runoff from the airport are treated at the recovery facility.
The 1993 season continued until June of that year due to the deicing requirements of the MD80
airplane.
GSI will treat the runoff from 80% of the new Denver International Airport (DIA) when
it opens.
A-10
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Appendix A - Case Studies and Evaluation
4. Process Description
The recovery system is a three stage process of primary filtration, nanofiltration, and
distillation. Oils, greases, grit and suspended solids are removed during the primary filtration
stage using a disposable cartridge filter. The filter is rated for removal of solids to 0.1 micron.
Polymeric additives, such as corrosion inhibitors and surfactants, are removed in the
nanofiltration stage. Only those additives with a molecular weight greater $ian 500 are
removed. Typically, additives make up 1% -2% by weight of the glycol that is used on
airplanes. The filtration membranes were supplied by Zenon Environmental.
The effluent stream from the nanofilter is fed through heat exchanges and then
discharged to a distillation tower. There are three distillations towers in series at the recovery
facility. During the distillation stage, water is removed from the liquid stream. The GSI facility
operates at 5,000 gpd. Antifoaming agents are added to the glycol solution at the inlet to the
distillation tower because of the surfactants in the glycol. Dissolved salts have not been detected
in the spent ADF collected at Stapleton, so the removal of ionic species has not been required
by an ion exchange unit.
5. Performance Data
Typically, the contaminated runoff from Stapleton Airport has an average glycol content
of 28%. The recovery system produced an effluent stream with an average glycol content of
98.5%, with the remaining portion being water.
A-ll
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6. Process Reliability
Appendix A - Case Studies and Evaluation
The recovery system must produce an effluent that meets performance specifications set
by the reuser. GSI indicated that the system consistently produces an effluent that meets those
specifications.
7. Maintenance and Energy Requirements
f
No backwashing is required for the filters. Filter residuals, containing non-toxic solids,
are landfilled. Periodic maintenance is required for the pumps and heat exchanges.
i
8. Costs
The greatest cost associated with the recovery system is the cost for the fuel that is used
in the distillation process. Therefore, it is most cost effective when the contaminated runoff
contains a high percentage of glycol. According to the vendor, the recovery process is cost
effective when there is at least 15% glycol in the contaminated runoff. In addition, the recovery
system produces a high glycol percentage (>98%) to reduce transportation costs. Unlike the
European airports where glycol can be recovered and reused at the airport at a concentration of
50%, the recovered high percentage glycol is transported to manufacturers in the US.
Transportation costs for low percentage recovered glycol are extremely high.
The complete capital cost for the airplane deicing/anti-icing operations and collection
and processing of contaminated runoff at the new Denver Airport is estimated at 20 to 25 million
dollars. The same complete capital cost for Denver's Stapleton Airport is estimated at 6 to 7
million dollars.
A-12
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Attachment B - Airplane Deicing Fluid Recovery Systems
Information Checklist
ATTACHMENT B
AIRPLANE DEICING FLUID RECOVERY SYSTEMS
INFORMATION CHECKLIST
*
1. Company Name:
2. Company Address:
3. Contact Name:
phone
fax
4. Current Status of Application
Locations Capacity (gal/hr) Startup Date
5. Process Description
(attach process flow diagram if available)
B-l
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Attachment B - Airplane Deicing Fluid Recovery Systems
Information Checklist
6. Performance Data
(provide operating data including influent and effluent glycol content %, and other
contaminant levels if measured)
7. Process Reliability
r
9
8. Maintenance and Energy Requirements
(include information on any wastes produced and disposal requirements)
9. Costs '
B-2
-------
Attachment B - Airplane Deicing Fluid Recovery Systems
Information Checklist
ATTACHMENT B
AIRPLANE DEICING FLUID RECOVERY SYSTEMS
INFORMATION CHECKLIST
•
1. Company Name:
2. Company Address:
3. Contact Name:
phone
fax
4. Current Status of Application
Locations Capacity (gal/hr) Startup Date
5. Process Description
(attach process flow diagram if available)
B-l
-------
Attachment B - Airplane Deicing Fluid Recovery Systems
Information Checklist
6. Performance Data
(provide operating data including influent and effluent glycol content %, and other
contaminant levels if measured)
7. Process Reliability
»
8. Maintenance and Energy Requirements
(include information on any wastes produced and disposal requirements)
9. Costs
B-2
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MUNICIPAL TECHNOLOGY BRANCH
EMERGING TECHNOLOGY REPORT:
Preliminary Status of Airplane Deicing
Fluid Recovery Systems
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