PB84-130384
Field Evaluation of Aeration Processes for
Oraanic Contaminant Removal from Groundwater
Hebolsine Kohlmann Ruggiero Engineers, New York
Prepared for
Municipal Environmental Research Lab,
Cincinnati, OH
1933
I
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EPA-600/D-84-016
1983
FIELD EVALUATION OF AERATION PROCESSES
FOR ORGANIC CONTAMINANT REMOVAL
FROM GROUNDWATER
by
Dominick D. Ruggiero
and
Walter A. Feige
EPA Cooperative Agreemenc "R8063 >5
MUNICIPAL ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION' AGENCY
CIN'CLXN'ATI, OH 45268
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TECHNICAL REPORT DATA
( P ease ,e d lnsrnicnons on the re ene be/ore comD1etm /
2.
3. RECIPIENTS ACCESSION NO.
4 1 30 38 4
.
PROCESSES FOR ORGANIC
GROUND WATER
j 5 . REPORT DATE
1983
6. PERFORMING ORGA ) IZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
Walter A. Feige
ADDRESS
10. PROGRAM ELEMENT NO.
Engineers, P.E.
BNC1A
11. CONTRACT/GRANT NO.
CR806355
ADDRESS
Research Laboratory—--Cin.,OH
Development
13. TYPE OF REPORT AND PERIOD COVERED
AWWA Proceedings —Nati Neetin
14.SPONSORING AGENCY CODE — 983
Agency
EPA/600/14
Féjge 513—684—7496
lb. AO iMALI
The results of the pilot plant evaluation of aeration methods for the
re moval of volatile organic solvents from ground water are presented. The project
took place at Glen Cove, Long Island, New York, where the concentration of
cis—l, 2—dichioroethylene, trichioroethylene, and tetrachloroethylene in
that cenmunity’s well water exceeded State Guidelines. Several aeration approaches
were examined, including diffused a2ration, packed column diffused aeration, cooling
tower aeration, induced air spray aeration (with and without packing), packed column
air—stripping, and air—lift pumping. Air discharging from some of the units was
sampled for potential air pollution problems. Capital and operating costs were
estimated for full—scale installations.
Several of the systems evaluated reduced contaminant levels to meet present New York
State guidelines.
I7 KEY WORDS ANO DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERSIOPEN ENDED TERMS
C. COSATI FicLd:Goup
S. OSTR.d 7ION STATEMENT
Release to Public
19SEC JRITY CLASS (This P.epørtj 31. NO. OP PAGES
Unc1as if led 27
3D. SECURITY CLASS iThupeqe 2. PRICE
Unclassified
EPA F.. —i R... 4..77) PREV OU$ E0.TION S OOSOLETE
1
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NOTICE
This document has been reviewed in accordance with
U.S. Environmental Protection Agency policy and
approved for publication. Mention of trade names
or commercial products does not constitute endorse-
ment or recommendation for use.
11
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FIELD EVALUATION OF AERATION PROCESSES
FOR ORGANIC COPflAMINANT REMOVAL
FROM GROUNDWATER
Dominick D. Ruggiero 1
and
Walter A. Feige 2
INTRODUCT ION
The discovery of contaminated groundwater in the United States and
throughout the world is constantly increasing and becoming a major
concern to public health officials. This is especially true for areas
depending on groundwater as the source of their drinking water supply.
One such area encompasses the City of Glen Cove, N.Y., where in 1977
a portion of the wells supplying water to the City was restricted
from use because of the presence of volatile organics in excess of
the New fork State guidelines. Faced with the problem of a reduced
water supply, the City of Glen Cove began evaluating methods to augment
their available supply. The City retained the consulting engineering
firm of Nebolsine Kohlmann Ruggiero Engineers, P.C. (NKRE) to determine
the most feasible and economical treatment system. Based on discussions
with the.U.S. EPA’s Municipal Environmental Research Laboratory Drinking
Water Research Division (MERL—DWRD) in Cincinnati, Ohio, it was deter—
i ined that rio treatment system existed at that time that was capable of
treating large volumes of water containing the organic contaminants
present in the Glen Cove groundwater. After preliminary testing,
funded by the City of Glen Cove, discussions and negotiations between
the C ty of Glen Cove, the U.S. EPA and NKRE resulted in a research
grant (later changed to a Cooperative Agreement) funded by the U.S. EPA
o test several possible treatment methods at the Glen Cove site. The
research program was operated in three phases, beginriina in the latter
oart of 1978 and was completed in the first quarter of 1983. While the
actual testing involved several possible treatment methods, such as
a sorption, this paper will present the results of the testing of
aeration methods.
Aeration - General
The use of aeration for the effective removal of volatile organics was
questionable at the beginning of this research project. Very little
was known at that time about the ability of aeration procedures to
remove volatile organic contaminants from groundwater. It was only
after preliminary testing at Glen Cove using aeration (1) and after
testing by the U.S. EPA in their Cincinnati, Ohio, laboratory on water
spiked with organic contaminants (2) that it was concluded that
aeration should be included as a part of the research project. Aera-
tion technology has developed substantially during the period of this
project. It has advanced from a questionable approach to one of the
best and most economical methods of removing volatile organic conta—
mipation from a groundwater supply.
1 Vice PresiJent - FJebolsine Kohlmann Ruggiero Engineers, P.C. —
New York, N.Y. 10301
2 Physical Scientist, Drinking Water Research Division, Municipal
Environmet tal Research Laboratory. U.S. Environmental Protection
Ac,ency, Cincinnati, Ohio 45268
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The testing at the Glen Cove site has also proven that the use of aera-
tion has little or no impact on the ambient environment since, unlike
other treatment technologies, such as adsorpticn, aeration does not
require recovery, regeneration or chemical use and does not produce a
waste product for disposal. The amounts of contaminants stripped from
the water also have insignificant impact on the ambient air. During
the research project several aeration approaches were tested. These
included: diffused aeration, packed column diffused aeration, cooling
tower aeration, induced air spray aeration (with and without packing),
packed column air—stripping and air—lift pumping.
Aeration Testing Pilot Plant Facilities
Following the approval of the initial request and each phase extension,
the plans were reviewed with U.S. EPA (MERL-DWRO). After approval by
DWRD the necessary equipment was purchased and installed or the
required modifications were made to the existing testing equipment.
The testing in all three phases was located at the Carney S treet well
site in Glen Cove, N.Y., where the highest concentrations of conta-
minants were found. Well No. 22, which draws water from an aquifer
about 160 feet (49 m) below ground level and has a pumping capacity of
about 2 mgd (7570 m3/day) , was utilized as the main water supply to
the test units in all three phases.
The required analysis for all phases was performed on analytical
instrumentation purchased in Phase I. The analytical instrumentation
shown on Fioure 1 included a Traccr* gas chromatograph equipped with
a halogen-specific electrical conductivity detector and a Tekmar
pt ’r e— nd-tr p concentrator. The gas chromatograph was also equipped
with an automatic integrator which determined the area of the peaks and
printed out the re;ults.
The aeration method tested during Phase I, diffused aeration, was the
only method tested during all three pilot plant phasea. The water to
b treated by diffused aeration flowed first through an impact flow
meter and a flow totalizer before entering an acrylic aeration column,
shown on Figure 1. The influent water entered at the top of the
column and discharged through a pipe attached about 2 feet (0.61 m)
above the base of the column. Air for the unit was supplied by a
blower (shown on Figure 1) and the air flow was measured by a mano-
meter. Air was diffus€d at the bottom of the column by five cylin-
drical porous stone diffusers. This arrangement resulted in the air
flowing countercurrently to the water.
Phase 11 aeration testing included use of the diffused aeration
column previously described and the addition of a packed column
diffused aeration unit and a small cooling tower (Manufacturer’s
demonstration unit). These units are shown on Figure 2. The packed
column diffused aeration unit consisted of an acrylic column identical
to that used for the initial diffused aeration testing. Six feet of
packing material, purchased from Hunters Corporation, was placed in
the column. Air was supplied to this column below the packing by
the blower used in Phase 1 and was distributed either by cylindrical
porouS stone diffusers or a hole in an ai’ pipe at the center of the
packing. The cooling tower unit installed was a small demonstration
model of an induced draft cooling tower provided by baltimore Air Coil
* Mention of trade names or con ercial products does not constitute
endorsement or recomendatiOn for use by the U.S. EPA.
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(shown on Figure 2). This model is based on a self—sustaining aeration
system requiring no outside source of energy other than the water
pressure itself.
Utilizing the results of Phases I and it and after consultation with
the U.s. EPA, major additions and modifications to the pilot plant
equipment were made for the Phase Ill testing. The modifications
included modifying an aeration column so it could be used to evaluate
air spray aeration, utilizing induced air, the installation of an
air—lift pump in a well, and the addition of a second blower.
To evaluate induced draft air spray aeration one of the columns used
in Phase Il was modified by installing a spool placed between the base
and the first Section to allow ambient air to enter. A fan was
installed on the top of the column to draw the air up through the
column. The water was supplied to the column through a distribution
header, the configuration of which was varied during the test period.
The column was initially operated empty but the Munters packing,
purchased in Phase I, was added during the test period.
During the Phase III test period U.S. EPA personnel delivered,
installed and operated a mobile packed column air—stripping unit at
the Glen Cove site (3). This unit contained about 18 feet (5.51 m)
of 1—inch (2.5 cm) olastic saddle packing purchased from Glitsch
Company. the water entered the top of the column and ambient air was
induced at the base of the packing.
Well No. 20 at the Carney Street site was converted to an air lift
pump operation so that this approach to air—stripping could be
evaluated. This was accomplished by pulling the existing pump in
Well No. 20 and replacing it with a fabricated air lift pump. This
pump utilized the air from one of the blowers of the diffused aeration
system as its air supply. The units for Phase 1111 are shown on
Figure 3.
Aeration Testing Proqram and Operations
The main objective of the aeration portion of this research program
was the ev3luation of the basic effect of aeration methods for the
removal of trichioroethylene, tetrachloroethylene, cis— ,2—dich1oro—
ethylene and l,1,l—trichloroethane from groundwater sources used as
drinking water supplies. The pilot plant program evaluated the
aeration methods at various air to water ratios, various distribu-
tion configurations and water application rates.
The d ffised aeration and packed diffused aeration columns had a
constant water flow of 28 gal/mm (6.4 m3/hr) which corresponded to a
residence time of about 10 minutes. The air to water ratio was varied
by changing the air flow. Air to water ratios for the three phases
varied from 5 l to 30:1. Since the packed column diffused aeration
system ad two methods of introducing air (spargers and a hole in the
air pipe) both were tested.
The small demonstration cooling tower unit generated its own air draft
requiring the air to water ratio to be determined by field meazurements.
The air to water ratio was related o the incoming water pressure.
The air to water ratio for tne induced air spray aeration column was
varied by changing the water flow to the column because the fan instal-
led at the top of the column had a constant speed producing 2500 cfm
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of air. The distribution system at the top of the column was altered
several times ano the final arrangement included five nozzles manu-
factured by Soraying Systems Co. The column was initially operated
empty with packing added in the later part of the program.
The packed column air—stripping unit is a portable test unit which
was tested at.the Glen Cove site twice by U.S. EPA personnel during
the third phase of this research program. The column contains appro-
ximately 18 feet (5.49 m) of plastic saddle packing and is 24 inches
(0.61 m) in diameter. The column was tested at air to water ratios
ranging from 5:1 to 85:1. The ratios were changed by varying both
the speed of the blower inducing the ambient air and the water flow.
Samples of the appropriate influent from Well No. 22 and the effluent
from each test unit were sar p1ed for analysis on the scheduled
sampling days. Units which did not run continuously were operated
for at least one hour before sampling occurred.
The only system which did not have Well No. 22 as the source of the
water being tested was the air—lift pump which was installed in
Well No. 20. The air to water ratio was varied by increasing or
decreasing the submergence of the air pipe in the well and varying
the air applied to the well. Flow from the pump was computed using
the measured flow over a 90 degree V—Notch weir. The influent sample
was taken from the same well using a pipe installed outside the
eductor pipe of the air-lift pump. Prior to sampling the effluent
the pump was allowed to operate for one hour to insure stability.
Since aeration processes transfer contaminants from the water to the
ambient air it was necessary to determine the impact on the ambient
air. To accomplish this air samples of the air discharging the
various units were taken and analyzed for the contaminants under
study.
RESULTS
Diffused Aeration Studies
The only aeration method which was tested in all three phases was the
diffused aeration method. This approach was operated at air to water
ratios of 30:1, 20:1, 15:1 and 5:1. The results of the Phase I
operation, which are summarized on Figure 4, indicate that diffused
aeration can meet the present tiew York State guidelines for the conta-
minants tested which was also confirmed in Phases II and III. These
guidelines are 50 ugh pe’- contaminant and a total of 100 ugh for
all organic contaminants.
Testing in Phase II, which involvea the evaluation of packed column
diffused aera’ ion and two—stage diffused aeration, indicated an impro-
vement in removal efficiency using two stages or packing. The packed
column diffused aeration system, which operated with the packing
flooded and uriflooded and used two r?ethods of air distribution,
showed removals similar to those achieved by plain diffused aeration
but at lower air to water ratios. This was achieved using the
unflooded conditions with air distribution utilizing por&js sp rger
stones. A summary of the data is presented on Tables 1 and 2 and
summarized oraphically on Figure 5. Toe two-stage diffusion aeration
results, which are summarized on Table 3, indicate that for a given
air to water ratio, two—stage operation resulted in substantially
greater removals than single—stage operations.
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I! 4tLced Air spray Aeration Studies
The original reason for testing this approach was to determine the
effect of s rav aeration as a method of removing volatile organics
from a water supply. The initial approacn was the use of several
nozzle arranqements to distribute the water across the column. It
was determined after initial testing that the contact time between
the water and air in the column was insufficient to achieve desired
removal efficiencies. Since it was not possible to increase the
height of tne column, packing was added in stages and the induced air
packed column spray aeration approach was evaluated. Packing
manufactured by Munters Co. was installed in the column. The first
evaluation utilized two feet of the packing which was increased to
four feet. With four feet of the packing it was possible to remove
more than 9Q of the organics present and produce water of a quality
which should be acceptable under most conditons. Typical results are
shown on Figure 6. Due to project time constraints it was not possible
to further increase the depth of packing.
! acked Column Air Stripper Studies
Twice during the Phase III operation U.S. EPA personnel installed and
operated tneir own packed column air stripper at the Glen Cove, N.Y.,
site. The unit operated with approximately 18 feet of plastic saddles,
manufactured by Glitch, Inc., and was operated at air to water ratios
ranging from 5:1 to 65:1. The removal efficiency ranged from 60 to
greater than 95 percent depending on the air to water ratio used. This
approach prociuced a water quality meeting present New York State guide-
lines and most other areas at air to water ratios of 15:1 or greater.
Typical results of the testing at the Glen Cove site is shown graphi-
cally on Figure 7.
Air—Lift Pjmpinc Studies
Since there was no coni nercia1)y available air—lift pump to suit the
desired operating conditions the pump utilized for this study was
fabricated on site. Since the only data available on air—lift pumping
as an air—stripper indicated that a minimum 10:1 air to water ratio
was required, all testing was performed at ratios of that level or
hIgher. The testing results indicated that the removal efficiency of
this method of air stripping was low, with only about a 50% reduction
in the overall average organic removal. A sun uary of the results is
presented on Table 4. It should be noted that many problems in ope-
rations were encountered and considering the relatively poor results,
it was evident that the air-lift pumping system did not appear suitable
as a practical metnod for efficient removal of organic contaminants
from water.
Cooling Tower Studies
A small demonstration model of an induced draft cooling tower was
evaluated during Phase II. Utilizing an air flow meter it was deter-
mined that thIS unit was capable of producing air to water ratios
ranging from 200:1 to 700:1 at flow application rates øf 2 gpm to 4
gpm respectively. Based on testing in this range, the removal effi-
ciency was r.,ther low, between 48 and 61 percent average for the con-
taminants present. However, it should be emphasized that the unit
used was a d ,ilon5tratiOfl unit for sales pu—poses and a unit designed
for a speciflC purPoSe, or another type of cooling tower unit, could
possibly be .uitable for th treatment of contaminated groundwater.
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Air Sampling
There has been concern about the transfer of contaminants from the
water to the ambient air, thereby causing an air pollution problem.
To study this problem, air sampling and analysis were conducted on
the air discharging from several of the systems evaluated in addition
to the ambient air in the area. The major portion of this sampling
was performed during Phc.,e III. These data, along with the computed
theoretical values, are presented on Table 5. Also included in
Table 5 are OSHA 8-nr workroom standards (4), the only air quality
standards known U exist for these contaminants. In many instances,
the levels found were higher than the computed theoretical value.
This discrepancy was believed to have been caused by the pickup of
moisture in th air sample which would not have been a factor jc a
mist eliminator were used. When comparing the actual analytical
results, the computed theoretical values for the discharged air and
the OSHA workroom standards, it is apparent that none of the aeration
systems had any appreciable impact on the air in the vicinity of the
treatment units and after dilution with the contaminant-free ambient
air, the contaminants would be at levels below the detection limits.
Ambient Air Effect on Water Quality
The ambient air used in the induced aeration system may have an effect
on the quality o.f the treated water and to evaluate one aspect of this
possible effect, suspended solids and particulate analyses were
performed on the influent and effluent to each aeration method tested
in Phase fri. The results of this testing indicates little to no
effect on the treated water quality. It should be noted that the
ambient air in the Glen Cove area is relatively clean and the effect
must be evaluated in an area where air pollution is present. If high
dust loads are present in the ambient air, a significant solids load
could be imparted to the treated water.
Aeration Studies Summar ;
The data developed during the research project for all six aeration
methods tested are compared and sun narized on Table 6. This surnary
indicates that the best removals were achieved by the packed column
air stripper closely followed by the induced air packed column spray
aeration system. The iowest overall removal was achieved by the air-
lift pumping system.
Estimated Costs for Full—Scale Installations
The diffused aeration system, packed column diffused aeration system,
induced air packed spray aeration system, and packed column air strip-
per can be designed and installed for a full—scale operation. The
units will be capable of meeting the present New York State guidelines
and produce a quality of water which thould be acceptable in most
other areas. Further evaluation of the air—lift pump system must be
made before a decision as to the adaptability of these systems can be
made.
Flows of 1, 2 and 5 mgd (3,785, 7,575 and 18,925 m3/day) were utilized
to obtain a range of costs for a full-scale installation. The cost
estimates are based on costing information available in February 1983.
All estimated capital costs include required buildings for mechanical
and electrical equipment but not laboratory, offices or facilities for
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workmen. The estimated capital ccst for five of the aeration systems
tested during this research project are compared on Figure &. These
estimated capital costs indicate that the packed column air—stripper
system has the lowest capital cost, and the packed column diffused
aeration system has the highest estimated capital cost. A comparison
of the estimated annual operating cost per 1000 gallons (3,785 liters)
of treated water considering an electrical cost of $0.09/kwh for all
systems tested is presented on Figure 9. These estimated annual
operating costs for the systems show that the packed ..olimn air-
stripping system has the lowest operating cost while the air-lift
pumping system has the highest operating costs.
CONCLUSIONS
General
The following conclusions are aoplicable to all aeration methods
tested during the three pha s except as noted under tue particular
process unit.
1. Aeration as a technique for the treatment of volatile organics
present in groundwater will reduce cis—l,2-dichloroethylene,
trichioroethylene, tetrachioroethylene and I ,l ,I—trichloroethane,
to levels which will meet present tiew York State guidelines
and to levels that may be universally acceptable.
2. Most of the systems evaluated can be detailed designed and a
full-scale plant installed. Some of the systems will require
additional testing to determine the most economical design
parameters.
3. There is no apparent effect on the ambient environment. Air
discharging from the units contains levels of contaminants below
any existing air standards and the concentrations may not be
measurable after mixing with the ambient air. The aeration
units do not produce any liquid or solid wastes which must be
disposed and, therefore, will have no impact in that respect.
4. There is no apparent effect on the final water quality particu-
lar levels contributed by ambient air quality for systems using
induced ambient air. This is based on the ambient air conditions
at the Glen Cove, N. ’., site and sho d be confirmed at other
sites, especially in areas where air pollution is prevalent.
Diffused Aeration Studies
1. To achieve desirable water quality the diffused aeration system
must operate t an air to water ratio of 15:1 or higher. Using
this air to water ratio the system will remove between 60—95
percent of all compounds tested with an average overall removal
of approximately 84 percent.
2. The removal efficiency can be ir;creased by adding a second stage
diffused aeration unit or possibly by increasing the height of
the diffused aeration unit.
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Packed Column Diffused Aeration Studies
The use of packing material produced a slight improvement over that of
diffused aeration, achieving an overall removol of contaminants at
about 83 percent using air to water ratios of 10:1. The system must
be operated with the packing above the operating water level to achieve
these results.
induced Air Spray Aeration Studies
The testing in Phase ITT concluded that this approach required packing
in the unit to provide enough air to water contact time to achie #e
acceptable levels. Using at least 4 feet (0.12 m) of tiunters Corpora-
tion packing the overall reduct on of organic contamination was better
than 90 percent.
Packed Column Air-Stripping
The test cchunn used for this evaluation was designed and delivered to
the site by U.S. EPA personnel who installed it and operated it during
the two test periods. This unit used plastic saddles, purchased from
Glitsch, Inc., and had the highest overall removal efficiency,
exceeding 95 percent, of all aeration methods evaluated,
Ai,’-lift Pumoing Studies
The system exhibited very poor efficiency, about 50 percent, in
removing the volatile organics. This approach requires additional
evaluation before it can be considered for full—scale operation.
! nduced Draft Cooling Tower Studies
The unit used to evaluate this method was a small demon traticn model
supplied by B 1timore Air Coil. It was difficult to control the air
to water ratio and the unit had a rather low removal efficiency
between 48 and 61 percent. The water quality produced did not meet
present New York State guidelines and the unit is not considered ready
for full—size scale—up. Additional testing is required before this
type of unit could be reconinended for a full-sized installation.
kEC0MME? DAlI ONS
Reviewing the data d veloped during this entire research project, it
is apparent that information is dependable for some systems to allow
for the design and insta 1ation of full—scale units while cther
require additional testing to determine the optimum and most economical
design parameters. Some of the units evaluated do not appear to be
feasible and additional testing is not warranted. The foflowing are
recommendations to further develop the t.eatment system to remove
organic contamination from a groundwater supply which should be
considered for other research prejects:
1. A full—scale demonstration plant should be installed to evaluate
air—stripping of contaiiinaflts on a continuous basis.
2. Additional testing should be performed to evaluate the economics
and optimum conditions for severa types of packing material,
including the proper hydraulic loading .and air to water ratio for
each type of packing.
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3. The effect of ambient air conditions on systems utilizing induced
ambient air should be further evaluated and e.xpanded to inciLde
potential contaminants other than suspended matter. e g... bacteria
aM viruses. The testing should be conducted in a potentially
high air pollution area.
REFERENCES
(1) Technical Memorandum, “Well Water Supply Testing for the Removal
of Oryanic ContamInants,” prepared for the Office of the Mayor -
City of Glen Cove, N.Y., by Nebolsine Kohlmann Ruggiero E, gineers,
P.C. , April 1978.
(2) Private Cotmuinications with Dr. 0.T. Love, U.S. EPA, Cincinnati,
Ohio, November 1977.
(3) Michael D. Cuninins and James J. Westrick, “Packed Column Air
Stripping for Removal f Volatile Compounds,” 1982 Conference of
Environmental Engineers, American Society of Civil Engineers.
(4) General Industry Standards OSHA S.fety and Health Standards
(29 CFR 1910) U.S. Department of Labor, Occupational Safety and
Health Administration, OSRA 2206, Revised November 7, 1978.
(5) “Removal of Organic Contaminants from Drinking Water Supply at
Glen Cove, N.Y.: Phase I ,” U.S. EPA — 6OO/2-80—19 (1980).
(5) “Removal of Organic Contaminants from Drinking Water Supply at
Glen Cove, N.Y.,: Phase II, ” U.S. EPA — 600/2-82-027 (1981).
(7) “Removal f Organic Contaminants from Drinking Water Supply at
Glen Cove, N.Y.: Final Report, Final Draft..
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(b) Phase I - Diffused
Aeration Column
(a) Phase I — Analytical
Instrumentation
(c) Phase I - Blower
for Diffused
Aeration Column.
On he wall is
the manometer
which measures
the air flow.
FIGURE 1
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Phase II — Packed Aeration
Col umn
Phase U - Aeration
Testing (induced
Draft Cooling Tower,
Packed Aeration
Column and Diffused
Aeration Column from
Phase I)
Phase II — Induced
Draft Cooling Tower
FrGURE 2
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Phase III — U.S. EPA ’s Packed
Air Stripping Column
PHASE III — Diffused Aeration Column
and Spray Aeration Cnlumn with
Packing.
PHASE 111 — Air-lift Pumping System
F GU E 3
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0.
10 : 1 I5!I
AIR : WATER RATIO AIR:wATER RATIO
AVERAGE PERCENT REMOvALS AT SELECTED AIR:WATER RATIOS FIGURE 5
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TABLE 1. AERATION COLUMNS PERFORMANCE (Averaae values ln”ug/l)
C c l Pac i .à1 .F Pa? ru * eflT mn-H Packe11 colu?nn-H
Air: — .Jfioodcd) _JUoFooiedj_ Jiioode _( ! L_
Water Contaminant Ave. Ave. Ave. Ave. Ave. Ave. Aye. Ave. Ave. Ave. Ave. Ave. Ave. Ave. Aye.
Ratio lnfl. (ff1. Ruinov. infi. (111. Remoy. Intl. (ff1. Rcniov. Infl. Effi. Remov. Intl. [ ff1. R mov.
cis-! ,2—dichloro—
ethylene 62.3 27.8 55 62.3 37.8 71 62.3 20.8 67
Trich1or -
ethylene 131.1 47.4 64 131.1 23.0 82 131.1 35.3 73
ietract ioro-
vthy lcne fl 5,7 41.7 73 155.7 18.8 88 155.7 29.8 81
• 1,1— trlçhloro—
thane 4.0 1.73 57 4.0 3.0 75 4.0 1.5 63
c4 -1,2-dich1oro—
ethylene 43.2 13.5 63 41.1 14.6 64 54.7 13.0 16 40.7 16.0 61 54.7 15.1 72
Trichioro-
ettiyIi ne l5(’.2 311.8 74 152.9 35.6 77 149.0. 2 .4 84 152.9 41.6 73 149.0 28.6 81
10:1
ethykne 85.0 17.8 79 75,0 10.9 85 122.0 12.8 88 74.4 13.6 82 122.0 16.7 86
1.1. 1-trichloro-
ethane 3.8 1.2 68 3.8 1.1 71 4.0 0.7 82 3.7 1.3 65 4.0 0.9 77
cis-l .2-dichloro-
ethylene 36.5 8.6 76 36.5 11.6 68 36.5 11.2 69
Trl h1oro-
15:1 ethylene 170.8 23.3 86 170.8 31.0 82 170.8 28.9 83
Tetrachloro-
ethylene 49.0 4.4 91 4 .0 5.9 83 49.0 5.5 89
,1,l—t,1’ .h1oro -
et iine 3.? 0.1 81 3.7 1.0 73 3,7 1.0 73
a Packed Column-S (oTunin packed using diffuser stones.
Packed Column-il Column packed with air Passing through a hole.
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TAELE 2
AERATION COLUMNS REMOVAL EFFICIENCY
(Average Overall percentage)
Column TyDe 10:1 l :1
Diffused Aeration 62 72 84
Packed-S-flooded - 74 78
Pecked-5 -Linf looaed 79 83
Packed—H-Flooded — 70 80
Packed-H Unflooded 71 79
Packed Co1ui n-S = Column packed using diffuser stones.
Packed ColunmH Column pcked with air passing throuch a hole.
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TABLE 3
ORGANIC Ct NTAMINANT PERCENT REMOVAL
Diffused Aeration Column
Total Organic Contamh’ant
Column Air to Water Ratio — Percent Removal
5:1 76.0
10:1 73.6
15:1 82.1
17:1 76.2
2 5:1 43.1
10:1 72.1
15:1 43.9
17:1 82.5
Combined 5:1 86.5
1C:1 93.3
15:1 89.9
17:1 95.5
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NKRE
300
260—
260
240
:
INDUCED AIR SPRAY AERATI(
AVERAGE:
____ AIR WATER RATiO
0 — 2260
________ —580 ____________
ç -NA1URAL DRAFT
WITH 2ft. I0.6 1m) MUP4TERS
PACKING INSTALLED
N COLUMN PERFORMANCE
WITH 4ft. ( 122m I MI.JN1ERS
rACiCIN INSTALtED
z
0
I -
4
I.-
U
U
z
0
C -,
TRICHLOROETHYLENE
180
60
4O
120
100
80
4C
20
I
91 JRE 6
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Concentration Profile
Glen Cove, NY — Trichioroethylene
1 inch Plastic Saddles
0
a
0
c )o
0
4J2
L
C
U —
C
0
U
. 4
a
0 2 2 3 4
Length of Tr’avel Through Column Cm)
FIGURE 7
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TABLE 4
GLEN COVE, 11.Y — PILOT PLANT — PHASE iI - AIR—LIFT PUMP SYSTEM
SUMMARY OF RESULTS (All values in ugh)
Average Influer.t Average Effluent
___________ jjj fluent Rangej ( Effluent Range )
67.1 41.
(28 — 129) (18 — 79)
132.2 52.8
(80 - 163) (31 - 74)
8.9 2.9
(5.8 — 18) (1.1 — 6.3)
1.9 0.8
(0.9 - 2.9) (NM - 1.6)
70.9 52.1
(57 — 137) (37 — 76)
133.5 62.6
(99 — 148) (45 — 73)
7.6 3.3
(6.7 - 9.9) (2.5 — 6.2)
1.6 0.8
(1.2 — 1.9) (0.5 — 1.7)
Air to Water
Ratio
15:1
to
27:1
30 1
to
83:1
Contaminant
cis—1 ,2—diclilornethylene
trich loroethy lene
Tetrachl oroethyl ene
1,1 ,l-trichloroethane
cis—1 ,2-dichloroethylefle
trichioroethylene
tetrachi oroethylene
1,1 ,1—trichloroethane
Average
Percent Rernoy i
37.8
60 • 1
67.4
57.9
26.5
53.1
56.6
50 • 0
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TABLE 5
GLEN COVE, N.Y. — PILOT PLANT - PHASE III - AIR SAMPLING AND ANALYSIS
SUMMARY OF RESULTS (An values in ppm - volume to volume)
A. Analyses at Glen Cove Site
Average
Average Computed
Va1i’. s Theoretical
Testir g Contaminant Fcund Values
1. U.S. EPA cis-i,2-dichloroethylene 11.608 1.99
Packed Column trichioroethylene 7.354 2.53
Air Stripper* tetrachloroethylene 0.700 0.29
l,l,l—trichloroethane N.D. 0.02
2. Diffused cis—l,2—dichloroethylene 3.868 1.84
Aeration trichioroethylene 6.163 2.74
Column tetrachioroethylene 0.250 0.39
1,1,1—trichioroethane 1.225 0.04
3. Spray cis—l,2-dich loroethylene N.D. 0.02
Aeration tricnioroethy lene N.D. 0.02
Column tetrachioroethylene N.D. 0.01
1,1,1—trichioroethane N.D. 0.01
4. Air—lift cis—1,2—dichloroethy lene N.D. Not
Pump* trichioroethylene possible
tet ach1oroethy1ene N.D. to
1,1 ,1—trichloroethane N.D. calculate
5. Ambient Air cis—1,2-dich loroethylene N.D. Not
trichioroethylene N.D. applicable
tetrachi oroethyl ene h .0.
l,l,l—trichloroethane N.D.
B. OSHA Standards (Time Weighted Average — 8-hr period)
Contaminant Standard
cis—l ,2—dichloroethylene 50
trichioroethylene 100
tetrachioroethylene 100
1,1 ,1—trichloroethanc 350
NOTE: Analytical detectable limits: 0.5 ppm
N.D. — Not Detectable C 0.5 ppm)
* Based on two sampling occurrences. All others based on four
occurrences.
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TABLE 6
SUMMARY OF AVERAGE OVERALL PERCENTAGE REMOVAL
FOR AERATION METHODS TESTED AT GLE I COVE, N.Y.
Range of Overall
System Percentage Removal**
1. Diffused Aeration
A. Single Stage 59-84
B. Two Stages 86-96
2. Packed Column Diffused Aeration 70-83
3. Induced Draft Cooling Tower 53-61
4. Induced Air Spray Aeration
A. Without Packing — Induced Air 52—77
- Natural Draft 43-63
B. With 2 ft (0.61 m) Packing 80-82
C. With 4 ft (1.22 m) Packing — Induced
Air 91-93
— Natural
Draft 81*
5. Packed Column Air Stripper
A. With 1—inch (2.5 cm) Saddles
- Induced Air 69-97
— Natural Draft 38*
8. With 2—inch (2.5 cm) Saddles
- Induced Air 63-95
— Natural Draft 72*
6. Air—lift Pumping 46-56
* Results Based On one day of Testing.
- •- - Function of Air to Water Ratio.
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t 00 _j 1 1 1
o0 - —
C PT. L COST ___________
200— —
COMPARISON I
U,
—I
-S
g
D
?
I000.
•,-;;: ‘ ‘
M.-
._..__.M
j
90 J
PACKED
8 CC, uY
C Fu D
IAER.TtOW
700 SYSTEM-\-
600’—
500—
•
s’ -i’ -.---, --
,
‘ 1’ -
I /-‘
j,y
If
‘I I
T
,
/
—:
3001: #6
—4
4 r: ..,ca s:
FrGURE 8
FLOW MG
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NKRE f
COMPARJSC OF NUAL CPER’ TING CDST
PER T )S D GALLONS TREATED
_____________ (E? ER Y COST at 9 ./rwI —
____ :
\ \ AiR —LIFT PUMP SYSTEM
AETC SYSTEM
P CKE COLUMN
, D FFIJSE AER T ON
7 ‘-. SYSTEM
--
_l
—
jR- STRIPPING EYSTEY—
1— — ‘ I —
CCS 9&3
2.0 30 40 50 60 70
FLOW MGD
FIGURE 9
U,
z
0
-J
-J
0
z
I , ,
p-.
C-
•1 )
0
L i
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