EPA/600/A-94/191
PILOT PLAHT INVESTIGATIOH OP ALTERNATIVE TREATMENT METHODS
by
Mark H. Griese
Presented at the 82nd Annual Meeting of the
Indiana Section American Hater Works Association,
February 20-22, 1990, Indianapolis, Indiana
Evansville Water and Sewer Utility
Evansvilie, Indiana
February, 1990
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PILOT PLANT INVESTIGATION OF ALTERNATIVE TREATMENT METHODS
Mark H. Griese
INTRODUCTION
Not unlike every other utility within the State, the Evansville
Waterworks Department is somewhat apprehensive about the impact
which the Amendments to the Safe Drinking Water Act will have on
it's Utility. In addition to those increased costs associated
with the more stringent monitoring requirements, the promulgation
of several specific regulations 'may necessitate significant and
costly changes in Evansville's current treatment practices and
treatment plant design. To more fully evaluate this impact and to
determine the most cost effective approach toward insuring
continued compliance, Evansville has initiated a treatment process
study utilizing a pilot plant testing facility. Although some
attention is being given to the optimization of all current unit
processes, specific attention is being devoted to the evaluation
of ozone and to increased chlorine dioxide capabilities for the
further reduction of disinfection by-products. Evansville has
already altered its disinfection scheme in its full-scale plant to
meet existing tribalomethane regulations. More stringent
impending regulations, however, require additional consideration
of viable disinfection alternatives.
The purpose of this paper is to describe the process by which
Evansville implemented it's pilot plant project, to indicate the
extreme degree of flexibility which a pilot unit affords a Utility
in determining treatment alternatives, and to discuss some of the
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preliminary data which Evansville has generated and how this data
has altered the originally designed approach to the project.
This process study is not Evansville's first experience with pilot
plant application. In the late 70's and early 80's, the
Evansville Utility engaged in a cooperative effort with the EPA to
evaluate the use of chlorine dioxide and to determine the
effectiveness of granular activated carbon for removal of organic
compounds present in the source water as well as any formed after
chlorine dioxide disinfection. The pilot plant selected for this
earlier project was a single train 100 gpm Neptune Micro-Floe unit
utilizing the conventional treatment processes of rapid mix,
floceulation, settling, and filtration. Although rather large and
lacking the flexibility required for the current study, this unit
did produce water which compared remarkably well with our full-
scale system. The data derived from this project convinced
Evansville officials that pilot-plant results could be used to
accurately project the effects of full-scale plant modifications.
IMPLEMENTATION OF PROCESS STUDY
As already indicated, increased speculation that more stringent
disinfection byproduct regulations could be promulagated as early
as 1992 led Utility officials to the conclusion that more
information was needed concerning possible disinfection
alternatives. Although.the low concentrations of chlorine dioxide
currently used as a pre-treatment measure have proven valuable in
maintaining Evansville's annual THM concentration well below 100
ug/L, this treatment methodology would not adequately insure
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consistent compliance if this MCL is drastically reduced. It was
the desire to address this issue and to obtain data concerning
those byproducts associated with other disinfection alternatives
that prompted the current project.
Due to the fact that full-scale testing is inefficient, cost
prohibitive, and could expose the public to a quality of water
that is less than adequate, it was pre-determined that a major
component of the process study would be a pilot plant evaluation
of potential treatment changes or plant modifications.
Specifications were developed for the procurement of the needed
professional services necessary to evaluate the current treatment
processes at Evansvilie's Hater Filtration Plant and to develop
treatment and operational recommendations based upon present and
proposed federal and state standards. After reviewing proposals
by a number of qualified engineering firms with specialized
experience relating to treatment process studies, the engineering
firm of Camp Dresser & McKee was selected by the Utility. Based
upon Evansville's objectives and Camp Dresser & McKee's
recommendations, the following Project Approach was developed.
* Review Raw Mater Quality data and Plant Operations Records
* Raw Water Quality Characterization
* Assess Future Treatment Requirements
* Optimize Existing Treatment Processes
* Evaluate Alternate Oxidants and Disinfectants
* Implement Pilot Study
* Evaluate Results and Develop Recommendations
* Develop Conceptual Design and Cost Estimates
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PILOT PLANT DESIGN
To address what was believed to be the most critical component of
these project objectives, a pilot plant was constructed by CD&M
that would not only simulate Evansville's conventional methods of
treatment, but would also provide the advantages of parallel
treatment trains, ozonation capabilities, and multiple filtration
columns for evaluating a variety of filter media combinations.
Upon arrival in Evansville, the pilot plant was installed and a
raw water connection was made to an existing low service main.
Provisions were made to, utilize the chlorine dioxide, chlorine,
and alum solutions employed within the full-scale plant. This was
done to insure a representative comparison and to eliminate any
inconsistencies which might occur by using dissimilar treatment
chemicals. All water produced by the pilot system would be run to
•
waste.
The pilot plant itself consists of a number of individual modules
that may be interconnected in a variety of different ways. It was
this feature that afforded the flexibility required for this
project. A description of the individual modules comprising this
pilot plant system follows.
* The Electrical Distribution Module provides and distributes
power to the rest of the Pilot Plant.
* The Influent Module performs the function of dividing the raw
water stream into two paths to supply the parallel treatment
systems and is equipped with an in-line turbidimeter for
continuous monitoring of the source water.
* The Ozonation unit is self-contained and is comprised of an
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ozone generator, supply-air drier and filter, ozone monitor,
ozone destruct unit, and two 6-inch diameter contact columns.
The system is counter-current with water entering at the top and
ozone/air being introduced at the bottom of each column. The
ozonated stream is then directed to the next downstream process.
The availability of two columns permits multi-step ozonation for
one treatment train or comparative testing in both treatment
systems.
* The two parallel Rapid Mix and Flocculation Modules are
constructed entirely of Plexiglas and contain two rapid mix
compartments and three flocculation chambers. Each of the five
basins has its own independent mixer which provides the
capability of achieving tapered flocculation. Injectors and a
static mixer are provided prior to the rapid mix for chemical
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pre-treatment. Provisions have also been made to feed chemicals
between the individual basins if so desired.
* Since sedimentation is one of the most difficult water treatment
processes to model on a pilot plant scale, the Sedimentation
Module uses tube settlers to achieve adequate turbidity removal.
Utilizing this method of sedimentation for the 2 gpm flow which
is characteristic of both treatment trains, the one hour
detention of this module achieves settled water turbidities very
representative of those in Evansville's full-scale plant. Like
the raw water influent module, each of these units is equipped
with a combination turbidimeter/recorder for continuous
monitoring of treatment efficiency.
* Settled water is pumped to four individual 4-inch diameter
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filter columns. Each filter control module is equipped with a
variable-speed pump which controls the flow through the filters
and, like the other key treatment points throughout the system,
a combination turbidimeter/recorder. Each filter is provided
with taps located at various depths of filter media which may be
used to monitor headless development and/or turbidity
penetration. For Evansville's project, two filters were filled
with sand and anthracite to simulate the full-scale plants
present design. The other two filters contain granular
activated carbon that can be operated in parallel with the dual
media filters or in series with them as a final treatment
measure.
BENCH SCALE TESTING
Prior to the initiation of pilot plant testing, bench scale
testing was performed to determine if the current unit processes
of mixing, coagulation, and flocculation in the full-scale plant
were being performed with optimum results for both turbidity
removal and THM precursor reduction. A variety of mixing rates,
coagulant dosages, and coagulant types were tested with no
significant improvement over existing full-scale plant production.
In an attempt to gain some preliminary data concerning ozone and
chlorine dioxide dosages and associated THM reduction, bench scale
testing was also performed using various ozone and chlorine
dioxide dosages and then monitoring the treated water for 3-day
trihalomethane formation potential. Although the reductions in
THMFP were somewhat less than expected for ozone, the results of
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this test did confirm the effectiveness of both oxidants in
reducing tribalomethane formation and gave some preliminary
indication of the results which could be expected by utilizing
various dosages in the pilot plant process.(Figures 1 & 2)
PILOT PLANT TESTING PROGRAM
With the pilot plant in place and preliminary bench scale testing
completed, continuous flow pilot plant testing was initiated to
further evaluate various treatment options. The initial testing
period was timed to coincide with that time of year in which the
highest trihalomethane formation potential is experienced by the
Evansville Utility. The key objectives of this portion of the
process study are to:
1. Attain Primary Disinfection
2. Minimize Disinfection Byproducts
3. Lower Annual Average THMs to < 50 ug/L
4. Select Secondary Disinfectant
To accomplish these objectives, the following appeared to be
Evansville1s treatment options:
1. Eliminate Chlorine Dioxide — Use Ozone
2. Keep Chlorine Dioxide — Add Ozone
3. Keep Chlorine Dioxide -- Add Granular Activated Carbon
4. Keep Chlorine Dioxide -- Add Ozone & Granular Activated Carbon
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OZONE DOSAGES VS. THMEP
EVANSVILLE - BENCH SCALE TEST //2
en
CL
b_
no
100
70
60
50
CO
0
0.5
1.5
OZONE DOSAGES (mg/L)
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CHLORINE DIOXIDE DOSAGES VS. THMFP
EVANSVILLE - BENCH SCALE TESTS #4 & #5
no
100
«M
0
0.5
1.5
CHLORINE DOSAGES (mg/L)
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Chlorine dioxide had certainly proven advantageous in reducing
THM concentrations in the full-scale system. Speculation,
however, that the combined residual of chlorine dioxide and the
byproduct ions of chlorite and chlorate would be regulated at a
level significantly below the current rscommended maximum of 1
mg/L, indicated that increasing the current chlorine dioxide
capabilities alone would not be adequate for addressing the key
objectives. The increased chlorite ani chlorate concentrations
resulting from elevated chlorine dioxide dosages would need to be
effectively removed prior to entering the distribution system.
Since a limited amount of information is available that indicates
GAG is relatively effective in accomplishing this removal, it was
believed that any treatment scheme utilizing chlorine dioxide
alone as the primary disinfectant would have to also include GAC
capabilities. The other options available would be to maintain
the current chlorine dioxide levels and supplement pre-
disinfection and pre-oxidation with ozone, or to eliminate
chlorine dioxide entirely from the treatment scheme. With
preliminary estimates that the addition of ozone or combined ozone
and GAC capabilities could cost the Utility in excess of 10
million and 50 million dollars respectively, the reason for
effectively reviewing and optimizing each treatment option was
apparent.
Each individual pilot plant test was designed to last from 3 to 5
days. With the wide variety of treatment options to be addressed,
and the fact that a distinct impact would have to be observed by
any one treatment combination to meet the desired objectives, this
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schedule would provide the roost optimum use of the pilot plant
during that time of year when the DBF formation was greatest.
Although not a surrogate for all disinfection byproducts,
trihalomethane formation potential was selected as that parameter
to be used to determine the preliminary "success" of each
treatment option. In addition to trihalomethane reduction being
one of the key objectives of the project, in-house analytical
capability for this parameter would expedite data turn-around and
the refinement of future scopes of work. Upon the generation of
sufficient data to determine the most optimum methods of
treatment, longer test periods would be implemented to verify
earlier results, to optimize all unit processes involved in these
particular methods, to gather data on other disinfection
byproducts, and to determine the impact of raw water seasonal
variations.
Test No. 1 of the pilot plant study was a three day evaluation of
THM precursor oxidation utilizing elevated levels of chlorine
dioxide as a pre-oxidant. Current application of chlorine dioxide
in Evansville's full-scale treatment system seldom exceeds 1.0
mg/L. This level of treatment has been selected because it is
adequate for maintaining annual THM levels below the current MCL,
and in consideration of minimizing residual chlorite and chlorate
in the finished water. Since this dosage has proven inadequate
for reducing annual average THM formation levels below the 50 ug/L
level specified as a project objective, concentrations of 1.5 mg/L
or higher would be applied during the process study.
One treatment train of the pilot plant was pre-treated using an
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average dosage of 2 mg/L of chlorine dioxide while the second
train was pre-treated with sufficient chlorine to maintain a free
residual throughout the process. Finished water samples were
collected from each of the two treatment trains, stored in the
presence of chlorine for a period of three days at a temperature
currently representative of the distribution system, and then
analyzed for THM formation potential. A river water sample was
also analyzed to monitor changing formation potential conditions.
Figure 3 shows the results of Test fl. The three day THMFP for
the river water was approaching 300 ug/L and the finished water
from the pre-chlorinated train exhibited a formation potential of
174 ug/L. The sample collected from the pilot plant system
utilizing pre-chlorine dioxide oxidation, however, showed a
significant reduction in formation potential with a three day
average of only 26.8 ug/L. This reduction apparently indicates a
considerable oxidation of THM precursor material by the elevated
chlorine dioxide dosage of 2 mg/L.
Test No. 2 was designed to provide a direct comparison between
a water treatment system using pre-ozonation and one using pre-
chlorine dioxide addition. The raw water supplying one of the two
pilot treatment trains was diverted through the ozonation module
where it was treated with an average ozone concentration of 1.2
mg/L. The second pilot train was again pre-treated with chlorine
dioxide. To provide a more direct comparison of the two
preoxidants, the chlorine dioxide dosage was reduced to 1.5 mg/L.
Figure 4 indicates the results achieved in Test 12. Although
exhibiting a distinct reduction in formation potential as compared
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THM FORMATION POTENTIAL COMPARISON
EVANSVILLE - PILOT PLANT TEST #1
L
i_
E
300
250
200
150
100
50
0
RIVER
PRE-CI2 PRE-002
SAMPLE TYPE
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TIIM FORMATION POTENTIAL COMPARISON
EVANSVILLE - PILOT PLANT TEST
350
300
250
200
150
100
50
0
RIVER
o
PRE-OZONE PRE-002
SAMPLE TYPE
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to the earlier tested pre-chlorination process, the ozone treated
water still exhibited a THM formation potential in excess of that
water pre-treated with chlorine dioxide. The increase in THM
levels in the chlorine dioxide system compared to those in Test 1
was more than likely due to both the increase in the raw water
formation potential and the 0,5 mg/L dosage reduction.
To again determine if the conventional treatment methods of
coagulation and flocculation could be further optimized for the
removal of THM precursors, Tests 3 & 4 of the pilot study were
geared for a direct comparison of ferric chloride and the
currently employed aluminum sulfate. Test 3 compared the two
coagulants directly with pre-chlorination being practiced in both
treatment trains. Nearly identical THM formation potential was
observed for both systems. In Test 4, the water in both pilot
treatment systems was pretreated with ferric chloride and the pre-
disinfectant scheme utilized in Test 2 was repeated. As in Test
2, both systems exhibited significant reductions in THMFP as
compared to the raw water. Although a slight improvement was
noted for the system pretreated with ozone, the difference was
minimal and it was determined that a significant reduction in DBP
formation could not be expected by altering coagulants.
The treatment applications used in Pilot Test No. 5 would again
compare identical dosages of chlorine dioxide and ozone. In this
test, however, ozone treatment would occur, not as a pretreatment
measure, but after the treatment processes of coagulation,
flocculation, and sedimentation. This study was designed to
determine if the efficiency of ozone oxidation could be increased
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by altering its point of application. As can be seen in Figure 5,
that treatment train being pre-treated with chlorine dioxide again
exhibited the greatest reduction in disinfection byproduct
formation potential. Although the THM levels of both systems were
somewhat higher due to tie increasing formation potential of the
raw water, pre-oxidation using chlorine dioxide still revealed the
greatest efficiency in reducing this disinfection byproduct.
Tests 6 & 7 compared chlorine dioxide treatment to a treatment
system utilizing both pre- and settled ozone application. Due to
a continued increase in raw water formation potential, both
systems were treated with 2.5 mg/L of the respective
disinfectants. The entire 2.5 mg/L dosage of chlorine dioxide
was applied as pre-treatment while the ozone was applied as a pre-
treatment measure and in the settled water at 1.5 mg/L and 1.0
mg/L respectively. Figure 6 shows the results of Test 7. The
elevated raw water formation potential was impacting both
treatment systems. By comparison, however, the chlorine dioxide
treated system still revealed significantly lower THM levels.
At this point in the project, it was beginning to appear that, at
least for Evansville's raw water source, chlorine dioxide was
going to be the pre-disinfectant of choice. The Evansville
Utility had anticipated ozone oxidation to prove more efficient in
reducing disinfectant byproduct formation. Although an estimated
10 million dollar capital investment would be needed to implement
ozone treatment in Evansville's full-scale plant, this alternative
was obviously more attractive than the 40 to 50 million that would
be needed for GAG to remove the chlorite and chlorate associated
16
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THM FORMATION POTENTIAL COMPARISON
EVANSVILLE - PILOT PLANT TEST #5
500
400
300
200
100
0
M
U,
RIVER SETTLED-OZONE PRE-CI02
SAMPLE TYPE
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CL
THM FORMATION POTENTIAL COMPARISON
EVANSVILLE - PILOT PLANT TEST #7
500
400
500
200
100
0
vO
CO
RIVER TWO STAGE OZONE PRE-CD2
SAMPLE TYPE
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with increased chlorine dioxide capabilities.
Pilot Test No. 8 repeated the comparison made in Test 2 with ozone
and chlorine dioxide both being applied as a pretreatment measure
at the higher 2,5 mg/L level. This test was performed to
reconfirm that single stage ozonation was as effective at reducing
THMFP as was the dual stage application performed in the previous
tests. As in Test. 2, chlorine dioxide again exhibited the greater
reduction at a percentage similar to those in the previous test
modes.
Hot to be dissuaded from our original perception, one last attempt
was made to improve those results obtained by ozone oxidation. A
number of studies have indicated that small amounts of hydrogen
peroxide used in conjunction with ozone application greatly
enhance oxidation capabilities. To test the applicability of
"Peroxone" technology in Evansvilie's process, Tests 9 & 10
directly compared a treatment system using pre-ozonation to one
using pre-ozonation and hydrogen peroxide addition. Figure 7
reveals the results of Test 10 after the hydrogen peroxide dosage
used in Test 9 was increased from 0.5 mg/L to a concentration of
1.0 mg/L. This test was performed for an entire week with every
effort made to identify some improvement in the ozonation/peroxide
process. As evident in Figure 7, no improvement was noted.
Although both trains exhibited formation potential variations
which compared remarkably well with those in the raw water, the
numbers generated for both treatment processes were almost
identical.
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TI-IM FORMATION POTENTIAL COMPARISON
EVANSVILLE - PILOT PLANT TEST #10
jr~ ^.
en
Q.
LJL.
500
400
300
200
100
0
RIVER
03
03 & H202
TEST DATES
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NEW SCOPE OF WORK
When the Pilot Plant study was still in its infancy, Evansville
made a request to the EPA Research Center in Cincinnati, Ohio for
supplemental analytical support for disinfection byproducts. In
consideration of the EPA's plans for the development of
regulations concerning these byproducts, it was believed that the
data generated could assist the EPA in its regulatory development.
As the data began to indicate the viability of chlorine dioxide
for primary disinfection, the EPA informed Evansville of bench
scale work being performed by Dr. Gil Gordon of Miami University
in Oxford, Ohio on minimizing the amount of chlorite and chlorate
in drinking water treated with chlorine dioxide. Dr. Gordon had
discovered that sulfur dioxide could be used to quantitatively
remove the chlorite ion concentration to below the 0.1 mg/L level.
This process, coupled with the minimizing of chlorate
concentrations by proper chlorine dioxide generation, would permit
the use of higher concentrations of chlorine dioxide with the
elimination and/or removal of chlorite and chlorate ion residuals.
Evansville now had a fifth treatment option. Although this method
of treatment, to our knowledge, has not been performed outside of
the laboratory, the implications of this technology warrant our
investigation. Because this research could determine the
viability of chlorine dioxide as a Best Available Technology
under the Disinfection Byproduct Rule, the EPA is now supporting
Evansville both financially and analytically in this endeavor.
In consideration of the previously generated data and the mutual
benefits which could be derived by both Evansville and the OSEPA,
21
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a new scope of work was developed to fully evaluate the use of
chlorine dioxide as a primary disinfectant and the reduction of
its byproducts by sulfur dioxide application.
Prior to the initiation of the revised scope of work, a number of
additions were made to the Pilot Plant to better evaluate this
treatment process.
A 30 pound per day chlorine dioxide generator was donated to the
Utility by Rio Linda Chemical Company to be used specifically for
the pilot study. In tests 1 - 10, chlorine dioxide from the full-
scale generation system had been transferred to a day tank for
application to the pilot plant. Tests indicated that an increase
in chlorate formation was occurring during this period that was
probably due to the presence of a low level chlorine residual in
the batch solution. Since control of the chlorate ion would need
to be accomplished by optimizing the generation process and by
removing the chlorite ion prior to post-chlorination, this new
generator was installed with the majority of the production stream
going to the full-scale plant and a small, but accurate,
percentage going to the pilot plant. This "slip streaming"
procedure was accomplished by utilizing chemical resistant
variable-area flowmeters. Based upon the analytically determined
concentration of the original chlorine dioxide solution, the
proper milliliter per minute setting is made to achieve the
desired disinfectant dosage. This method of chlorine dioxide
application is more accurate than the previously employed
procedure and it takes advantage of the newly installed
generator's efficiency.
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Secondary settling basins have also been incorporated into the
pilot plant to add an additional 90 minutes of settling and
contact time to the treatment system. This treatment addition was
made to more closely simulate Evansville's full-scale plant, to
provide a location for pH adjustment if so desired, and to provide
additional contact time for the chlorine dioxide prior to the
addition of sulfur dioxide. This additional contact time would
helf insure the bacteriological integrity of the water supply and
assist in monitoring the presence of a chlorine dioxide residual
beyond primary settling.
A sulfur dioxide system is also being added to the Pilot Plant.
Based upon the same principal as the chlorine dioxide system,
precision rotometers will be utilized to "slip stream" a small
percentage of an inductor generated sulfur dioxide solution. This
stream will be added immediately prior to the dual media filters.
The fourth and final addition to the Pilot Plant was the
attachment of four 20 gallon clearwells to each filter effluent.
These clearwells will permit post-chlorination for the removal of
excess sulfur dioxide and sampling points representative of
finished water quality.
A fifth piece of equipment was installed, not in the Pilot Plant,
but in the laboratory. An ion chromatograph for the detection,
monitoring, and accurate quantitation of chlorite and chlorate has
been obtained. Generating chromatorgrams similar to that produced
in gas chromatography, this instrument can accurately detect both
ions at levels below 0.1 mg/L. Since it was nearly impossible to
monitor these types of levels with the previously employed
23
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amperometric measurements, this instrument was essential for
determining the success of the new treatment process.
With these additions in place, the revised scope of work was
initiated.
The revised scope of work consists of five basic components.
1- Optimize Generator Ifficienc^ - A sufficient number of analyses
on the chlorine dioxide production stream will be performed to
insure that the generator is producing chlorine dioxide with
minimal chlorine and chlorate residuals.
2. Bench Scale Studies fjojr Reduction/Reroova 1 of. Chlorine Dioxide
and Chlorite - Bench scale studies will be conducted by the EPA
to determine optimum dosages of sulfur dioxide for achieving
chlorite and chlorine dioxide removal. Other dechlorinating
agents such as PAC and ferrous ion may be evaluated to
determine their potential for accomplishing the same task.
3. Demonstrate the Best Method vs. GAC - The major operational
scheme of this phase will consist of adding the sulfur dioxide
prior to the dual media for reducing chlorine dioxide and
chlorite. Post chlorination will then occur to remove any
excess sulfur dioxide. This process will be compared to one
utilizing the GAC columns for removal of the same constituents.
4. Comparison of Chlorine Dioxide and Ozone - Since chlorine
dioxide and ozone are probably the only disinfectants that can
be applied to the raw water and still meet the disinfection
byproduct regulations, they will be evaluated in parallel in
this phase.
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5. Optimization of Unit Processes - The purpose of the Phase of
the pilot study will be to optimize the most desirable
application by varying other unit processes. The effects of
alternative coagulants, varied pH ranges, and various points of
disinfectant application are examples of those unit processes
that will be examined during this study period.
Throughout the project, formation potential using chlorine will be
done on collected samples to determine the impact of post
chlorination. Compounds and surrogates that will be evaluated
include trihalomethanes, haloacetonitriles, haloacetic acids,
chloral hydrate, chloropicrin, chloropropanone, total organic
halide, and total organic carbon. Other byproducts, such as the
aldehydes and ketones, will also be monitored and evaluated.
Phases 1 and 2 of the Project are now ongoing. The EPA is
currently involved in the bench scale evaluation while Evansville
is optimizing the chlorine dioxide generation efficiency and
installing the sulfur dioxide system. Completion of the project
is expected by late summer.
CONCLUSION
In a rapidly changing regulatory environment, this project is
viewed by the Evansville Utility as an investment in the future
that could now potentially save the department millions of
dollars. Although not applicable to everyone, the specific
research being conducted by Evansville certainly underscores the
flexibility which a pilot plant facility provides a water utility.
25
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Whether it is used to optimize a current treatment process, to
determine the feasibility of retrofitting a new treatment
technique into an existing plant, or to design and size a new
facility, pilot plant testing certainly provides a utility with a
cost-effective approach for addressing these issues.
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TECHNICAL REPORT DATA
/Please read Instructions on the reverse be/ore comnletm
1 REPORT NO,
EPA/600/A-94/191
4. TITLE AND SUBTITLE
Pilot Plant Investigation of Alternative Treatment
Methods
6. PERFORMING ORGANIZATION CODŁ
3. R
5. REPORT DATE
7. AUTHOR(S)
Mark H. Griese
8, PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Offic$ of Research and Development
Drinking Water Research Division
10. PROGRAM ELEMENT NO.
US EPA
Cincinnati, Ohio
11. CONTRACT/GRANT NO.
45268
12. SPONSORING AGENCY NAME AND ADDRESS
13, TYPE OF REPORT AND PERIOD COVERED
Risk Reduction Engineering Laboratory, Cincinnati,OH
Office of Research and Development
OS Environmental Protection Agency
Cincinnati, Ohio 45268
Symposium Paper
14. SPOroscJMING AGENCY CODE
:YC(
EPA/600/14
15. SUPPLEMENTARY NOTES
Presented at the 82nd Annual Meeting of the Indiana Section American Water Works
Association, February 20-22, 1990, Indianapolis, Indiana PO=Ben1amin Lvkins
16. ABSTRACT TPgT^ZT^ (513) 559.7450
Describes the process by which Evansville implemented it's pilot plant project, to
indicate the extreme degree of flexibility which a pilot unit affords a Utility
in determining treatment alternatives, and t,Q~ discuss some of the preliminary
data which Evansville has generated and how this data has altered the originally
designed approach to the project.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIEHS/OPEN ENDED TERMS
COSATI Fiefd/Group
18. DISTRIBUTION STATEMENT
Release to Public
19. SECURITY CLASS (This Report}
Unclassified
20. SECURITY CLASS (This page)
Unclassified
21. NO. OF PAGES
2S_
22. PRICE
EPA form 2220-1 (R»». 4-77) PREVIOUS EDITION is OBSOLETE
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