U.S. Environmental Protection Agency Industrial Environmental Research EPA~600/7~77~106
Office of Research and Development Laboratory
Research Triangle Park, North Carolina 27711 September 1977
EFFECTIVE CONTROL
OF SECONDARY WATER
POLLUTION FROM FLUE GAS
DESULFURIZATION SYSTEMS
Interagency
Energy-Environment
Research and Development
Program Report
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RESEARCH REPORTING SERIES
Research reports of the Office of Research and Development, U.S.
Environmental Protection Agency, have been grouped into seven series.
These seven broad categories were established to facilitate further
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are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
6. Scientific and Technical Assessment Reports (STAR)
7. Interagency Energy-Environment Research and Development
This report has been assigned to the INTERAGENCY ENERGY-ENVIRONMENT
RESEARCH AND DEVELOPMENT series. Reports in this series result from
the effort funded under the 17-agehcy Federal Energy/Environment
Research and Development Program. These studies relate to EPA's
mission to protect the public health and welfare from adverse effects
of pollutants associated with energy systems. The goal of the Program
is to assure the rapid development of domestic energy supplies in an
environmentally—compatible manner by providing the necessary
environmental data and control technology. Investigations include
analyses of the transport of energy-related pollutants and their health
and ecological effects; assessments of, and development of, control
technologies for energy systems; and integrated assessments of a wide
range of energy-related environmental issues.
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This document is available to the public through the National Technical
Information Service, Springfield, Virginia 22161.
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EPA-600/7-77-106
September 1977
EFFECTIVE CONTROL OF SECONDARY
WATER POLLUTION FROM FLUE GAS
DESULFURIZATION SYSTEMS
by
Lanny D. Weimer
Resources Conservation Company
P.O. Box 936
Renton, Washington 98055
Contract No. 68-02-2171
Program Element No. EHE624A
EPA Project Officer: Fredrick A. Roberts
Industrial Environmental Research Laboratory
Office of Energy, Minerals, and Industry
Research Triangle Park, N.C. 27711
Prepared for
U.S. ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Washington, D.C. 20460
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ABSTRACT
This report describes the demonstration tests conducted to substantiate
the feasibility of using the vertical tube, falling-film, vapor compression
evaporator to concentrate the waste water from a flue gas desulfurization
(FGD) process. The test results show that the waste water from the Chiyoda
FGD Process can be concentrated up to 140 times and with recovery of more than
99% of the waste stream as a high quality water (less than 10 ppm). Two series
of tests were conducted, one with 0.095 m /day (25 gal/day) bench model evapor-
ator and the other with 22.7 m /day (6000 gal/day) pilot size evaporator.
Process conditions were identified and verified for scale free operation.
Heat transfer coefficients of 2.84 to 4.26 kw/m2 °F (500 to 750 BTU/hr ft2 °F)
were consistently achieved throughout the tests. A conceptual design and
economic study of a full size treatment facility were conducted which showed
that the capital cost will range from $2300 to $1350/m3/D ($8.71 to $5.11/gpd)
of waste depending on system capacity. The corresponding operating cost will
vary from $0.95 to $0.65/m3 ($3.59 to $2.46/1000 gal) of waste processed
depending on the waste water composition. The operating cost of the FGD
waste treatment process is significantly lower when credit is given for the
high quality water recovered from the waste stream.
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CONTENTS
Abstract ............................... iii
Figures ............................... v
Tables ................................ V1-
Abbreviations and Symbols ...................... vii
1. Introduction ......................... 1
2. Conclusions ......................... 3
3. Recommendations ....................... 5
4. Demonstration Test Program .................. 6
Test Equipment ..................... 6
Bench Model Evaporator ............... 6
Laboratory Research Unit .............. 6
Results and Discussion ................. 12
Literature Review and Glassware Tests ....... 12
Bench Model Tests ................. 15
On-Site Demonstration Tests ............ 25
5. Design Conditions for Full Scale Systems ........... 35
6. Economics .......................... 38
Appendicies ............................. 42
A. Test Equipment ........................ 42
B. Chiyoda Waste Water Chemistry ................ 44
C. Waste Volume Reduction During On-Site Tests ......... 59
IV
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FIGURES
Number Page
1 Bench Model Evaporator 7
2 Process Flow Diagram for Bench Model Evaporator 8
3 Laboratory Research Unit (LRU) 10
4 Process Flow Diagram for Laboratory Research Unit (LRU) ... 11
5 Bench Model Test Results - Run #1 (Heat Transfer Data) .... 19
6 Bench Model Test Results - Run #1 (Operating Data) 20
7 Heat Transfer Panel After Run #1 21
8 Bench Model Test Results - Run #2 (Heat Transfer Data) ... 22
9 Bench Model Test Results - Run #2 (Operating Data) 23
10 Heat Transfer Panel After Run #2 24
11 Mist Eliminator After Run #2 26
12 Waste Volume Reduction During On-Site Test 28
13 On-Site Demonstration Test Operating Data 30
14 On-Site Demonstration Test Heat Transfer Data 34
15 RCC Brine Concentrator Process Flow Diagram - Schematic ... 39
16 Capital Cost for Waste Treatment System 40
17 Operating Cost for Waste Treatment System 41
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TABLES
Number Page
1 Summary of Analytical Procedures 13
2 Results of Glassware Analyses 14
3 Bench Model Evaporator - Run #1 Analyses 17
4 Bench Model Evaporator - Run #2 Analyses 18
5 Chemical and Physical Properties of Evaporator Feed 29
6 Chemical and Physical Properties of Sump Concentrate 31
7 Properties of the Product Water from Evaporator 33
8 Composition of Neutralized Chiyoda Waste Stream 37
9 Composition of Concentrated Waste Stream from Evaporator .... 37
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LIST OF ABBREVIATIONS AND SYMBOLS
ABBREVIATIONS
B.P.R. -- boiling point rise kPa
BTU — British Thermal Units kWh
Cone -- concentrate 1
cm -- centimeter LC
CW -- cooling water LRU
D -- day m
Dist -- distillate mg
FGD -- flue gas desulfurization mg/1
gal -- gallon Mmhos/cm
g/1 -- grams per 1 iter
gpd -- gallons per day ppm
gpm -- gallons per minute SS
Hr -- hour Spec. Cond.
HX . -- heat exchanger Sp. Gr.
J -- Joules TDS
kg -- kilogram TS
Pas
kilo pascals
kilowatt-hour
liter
level control
Laboratory Research Unit
meter
milligram
milligram per 1iter
micromhos per centi-
meter
parts per million
Suspended Solids
specific conductance
specific gravity
Total Dissolved Solids
Total Solids
Pascal Second
SYMBOLS
°C
Ca++
CaS04
Cl"
F"
Fe
+++
UK
Mg"1
degrees centigrade
calcium ion
calcium sulfate
chloride ion
fluoride ion
ferric ion
bicarbonate ion
sulfuric acid
degrees Kelvin
magnesium ion
MgS0
N03"
Na+
NaS0
24
so2
S03
Si0
AT
magnesium sulfate
nitrate ion
sodium ion
sodium sulfate
sulfur dioxide gas
sulfite ion
sulfate ion
silica
heat transfer delta temp.
overall heat transfer co-
efficient
VI 1
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SECTION 1
INTRODUCTION
The Clean Air Act of 1970 has provided increased impetus to programs
directed to decreasing sulfur oxide (SO,,) emissions from new and existing
power plants and other facilities. A major concern in installing a flue gas
desulfurization process is the reduction or elimination of the secondary
pollution of the water by S02 scrubbers. Demonstration that these pollutants
can be removed from the scrubber waste stream by an available commercial pro-
cess will allay that concern.
This report describes a program conducted for the Environmental Protection
Agency (EPA) by Resources Conservation Co. (RCC) to demonstrate the practica-
bility of using the RCC Brine Concentrator to significantly reduce the secon-
dary water pollution resulting from flue gas desulfurization. The RCC Brine
Concentrator is a vertical tube, falling-film, vapor compression evaporator,
which has been developed to provide a highly energy efficient process for con-
centrating waste and blowdown waters. It is especially applicable to concen-
trating waste waters containing scale forming calcium sulfate and silica. Use
of the unique RCC seed slurry process allows concentration of such waste waters
far beyond the solubility limit of the normally scaling constituents without
forming scale on the heat transfer surfaces. Currently, RCC has several brine
concentrators operating or under construction in the Western United States and
Canada. These installation represent the only commercial evaporators possessing
the capability of concentrating these normally scaling waters without suffering
scale formation.
An appropriate program to demonstrate the feasibility of the RCC Brine Con-
centrator for reducing the volume of waste water from flue gas desulfurization
processes required on-site operation of the concentrator at an S02 scrubber
installation. The Chiyoda "Thoroughbred 101" scrubber installed at
1
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the Sholz Power Plant of Gulf Power Company in Sneads, Florida was chosen
for the on-site testing because it was producing a continuous blowdown stream.
The Chiyoda process removes sulfur dioxide from the flue gas via countercur-
rent scrubbing with weak sulfuric acid in a fixed bed absorber. The absorp-
tion of S02 by H20 gives sulfurous acid (H-SO-J which is catalytically oxi-
dized to hLSO*. The concentration of sulfuric acid in the scrubbing liquid
is maintained constant by continuous withdrawal to the crystallizer. In the
crystallizer this absorbent is partially neutralized by limestone to produce
gypsum. There are two waste streams from the process. One is flyash bleed
from the prescrubber, and the other is the scrubbing liquid bleed from the
crystallizer for water balance and control of the chloride concentration
in the scrubbing liquor. These two waste streams are combined, neutralized
by limestone and discharged to the liquid waste pond. This combined neu-
tralized waste water was the feed to the concentrator during the demonstra-
tion tests.
The demonstration program consisted of the following sequential tasks:
1) evaluation of existing chemical data on waste streams from the Chiyoda
process, 2) glassware evaporation tests to confirm predicted precipitation
levels and to establish operating conditions for bench model tests, 3) bench
model tests to verify operating conditions for the on-site demonstration
tests, 4) on-site tests to demonstrate the vapor compression evaporator's
long-term performance in concentrating scrubber waste water, and 5) esti-
mation of the capital and operating costs for a full-scale system.
The primary objective of this program was to demonstrate a way to re-
duce the volume of waste water from a desulfurization process to less than
4% of its initial volume. Test results have demonstrated the feasibility
of concentrating the waste stream from the Chiyoda FGD Process up to 140
times and recovering more than 99% of the waste stream as a high quality
water (less than 10 ppm TDS) for recycle back to the power plant.
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SECTION 2
CONCLUSIONS
The following conclusions have been developed based on the results ob-
tained in this demonstration program.
1) The test program has demonstrated the technical feasibility of using the
RCC falling film, vapor compression evaporator system for control of sec-
ondary water pollution from the Chiyoda FGD Process.
2) The discharge of waste water from the Chiyoda FGD Process can be reduced
to as little as 1% of initial volume with the remainder recovered as a
high quality water (less than 10 ppm TDS), suitable for recycle to the
process or other uses.
3) Long term, scale free operation of the RCC Brine Concentrator Process was
demonstrated.
4) Formation of scale on the heat transfer surfaces of the evaporator was pre-
vented by the use of the RCC seed slurry process.
5) No degradation of the heat transfer coefficient (U) due to fouling of the
heat transfer surfaces was encountered during the demonstration tests.
6) The small amounts of foaming encountered during the test period will not
adversely affect operation of the vapor compression evaporator.
7) The overall heat transfer-coefficient remainded unchanged for total solids
concentrations in the evaporator up to 400 g/1.
8) Due to the feed being saturated with calcium sulfate and to its inverse
solubility, scale inhibitor must be added to the waste water fed to the
evaporator at a rate of 15 ppm to prevent fouling of the feed heat exchanger
and deaerator.
9) At the very high concentration factors (140) attained during this demon-
stration program, the estimated energy consumption of a full size evapora-
3
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tor will be 2.6 to 3.2 kWh/m3 (98 to 121 kWh/1000 gal) of waste water con-
concentrated. At current installations operating at lower concentration
factors the energy consumption is 2.1 kWh/m (80 kWh/1000 gal) of waste
water concentrated.
10) The capital cost of a full size system for application in treatment of
FGD process waste water for capacities between 600 to 3200 m /D will range
from $2300 to $1350 m3/D ($8.71 to $5.11/gpd). The corresponding oper-
ating cost will vary from $0.95 to $0.65/m3 ($3.59 to $2.46/1000 gal) of
waste processed depending on the waste water composition.
11) The operating cost of the FGD waste treatment process is significantly
lower when credit is given for the high quality water recovered from the
waste stream.
12) Standard materials of construction are considered to be available for
fabrication of a RCC Brine Concentrator for use in this application.
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SECTION 3
RECOMMENDATIONS
Since this program has successfully demonstrated treatment of waste-
waters from the Chiyoda regenerable flue gas scrubber system at the Sholz
powerplant in Sneads, Florida, it is recommended that the brine concentration
system be evaluated for a lime-limestone non-regenerable scrubber system
using forced oxidation (lime-limestone scrubbers are in more general commercial
use at the present time). Recent research at EPA's laboratory in Research
Triangle Park indicates that forced oxidation by air sparging or injection
can effectively increase the sludge solids content to upwards of 80% solids.
This is equal to a reduction of sludge volume by 25 to 40% for lime-limestone
scrubbers. However, since this tightening of the scrubber loop will result
in considerable build-up of soluble dissolved solids including corrosive
chlorides a separate blowdown stream will be required to control the level
of these salts. Treatment of this blowdown stream by a brine concentrator,
would allow effective control of chlorides in the scrubber loop and reduce
the dissolved solids concentration in the sludge solids. It is estimated
that a 70% reduction of the chlorides and other dissolved solids concentration
could be effected by blowdown and evaporation of 5% of the filtrate liquor.
This compares with a blowdown requirement of about four times that amount if
forced oxidation is not used to convert calcium sulfite to calcium sulfate.
Since the sludge solids have been increased in solids to the extent that they
would easily be land-filled and the soluble salts concentration have been
reduced in the sludge liquid phase, the costs of sludge fixation may well be
alleviated.
If this work was to be successful it would "make possible the combustion of
high chloride, high sulfur coals without damage to the environment" .
1) Borgwardt, Robert H., Paper presented at FLUE GAS DESULFURIZATION SYMPOSIUM,
EPA/IERL, Hollywood, Florida, 8-11 Nov.77.
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SECTION 4
DEMONSTRATION TEST PROGRAM
The purpose of this test program was to demonstrate the technical feasi-
bility of using a falling film, vapor compression evaporator to eliminate
secondary water pollution from flue gas desulfurization processes. Data were
obtained to permit calculations for capital and operating costs, energy re-
quirements and other critical criteria needed for design of a full-size
treatment process.
The test program was conducted in four segments: 1) Evaluation of avail-
o '
able chemical data on Chiyoda waste streams, 2) Laboratory glassware concen-
tration tests, 3) Bench model evaporator testing, and 4) On-site demonstra-
tion tests.
TEST EQUIPMENT
Bench Model Evaporator
The bench model testing was conducted using the Resources Conservation
Company (RCC) 0.095 m /D (25 gal/day) vertical plate, falling film, laboratory
evaporator. A photograph and process flow diagram of the unit is presented
in Figures 1 and 2, respectively. The Bench Model Evaporator was selected for
initial evaporator testing since it provides small scale yet realistic simula-
tion of a full size evaporator. The fluid film which is formed on the vertical
heat transfer panel has essentially the same flow characteristics as the verti-
cal tubes used in commercial RCC evaporators and thus gives heat transfer and
process data applicable to the commercial plant. A detailed description of the
Bench Model Evaporator is given in Appendix A.
Laboratory Research Unit
The on-site demonstration tests were conducted with the RCC Laboratory
Research Unit (LRU). The LRU is a 22.7 m3/D (6000 gal/day), vertical tube,
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^HPtl
^•-^^
•A'l*
Figure 1. Bench Model Evaporator
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CW IN
CW OUT
--
-««
1
F
STEAM
CONDENSER
PLANT STEAM M >•
PLANT STEAM-*
CONOENSATE
TRIM
HX
1
VENT
A ©
' 1 PLANT Cad — J—
STEAM
1
->•
oo
CONDENSATE
OUT
\ \ \ \ \ \ \ \ \ \ V
FEED TANK
it
FEED/CONDENSATE
HEAT EXCHANGER
u
\ \ \ \ \ ^ \
FEED PUMP FILTER
PLANT
STEAM
DEAERATOR
PLANT
STEAM
CONDENSATE
EVAPORATOR
,.
HEAT
TRANSFER
PANEL 3 FT'
• FEED 'PUMP ON-OFF CONTROL
RECIRCULATION PUMP
CONCENTRATE
FIGURE 2: PROCESS FLOW DIAGRAM FOR BENCH MODEL EVAPORATOR
-------
falling film, vapor compression, pilot evaporator designed to simulate the
operation of a commercial size RCC evaporator. A photograph of the LRU is
shown in Figure 3. The basic process flow diagram of the LRU is shown in
Figure 4. A detailed description of the LRU is presented in Appendix A.
The neutralized Chiyoda waste water was piped to the evaporator through a
filter, flow meter, heat exchangers and deaerator. The feed enters the sump
at about its atmospheric boiling temperature. Evaporation occurs at slightly
above atmospheric pressure as the concentrated waste is recirculated down the
inside of the condenser tubes in a thin film. The steam is collected and then
compressed to raise its temperature of condensation slightly above the boiling
point of the brine on the inside of the tubes, and causes more steam to be
evaporated from the brine inside the tubes. The condensate is collected as
product water and pumped back through the heat exchanger to recover its heat.
The small concentrated slurry waste stream is taken from the recirculation
line, and is discharged periodically through a timer operated control valve.
Scale control is accomplished by utilizing a seed slurry method which pre-
vents scale deposition on metal surfaces by providing preferential sites with-
in the waste brine for crystal growth. The seed slurry is established in the
sump during startup by seeding the unconcentrated feed with calcium sulfate
and is maintained during operation by the natural precipitation of salts from
the concentrated brine. Chemical analyses of the calcium sulfate seed usually
show the presence of other ions. Some of these ions are from the brine left
on the precipitate when it is filtered because calcium sulfate is not suffi-
ciently insoluble to permit washing the precipitate. However, other ions and
salts may also co-precipitate by several mechanisms depending on the composi-
tion of the concentrated brine. Some of the possible mechanisms are; double
and triple salt formation with calcium sulfate as one component; substitution
of ions of similar size and charge in the calcium sulfate crystal lattice;
interstitial accumulation in the crystal lattice; and adsorption on the sur-
face of the crystals. Contamination of calcium sulfate seed to levels of the
order of 10% of other salts has been observed occasionally with no adverse
effect on scale control.
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Figure3. Laboratory Research Unit (LRU)
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FEED
•It
STEAM COMPRESSOR SYSTEM
PRODUCT
WASTE
BRINE
PUMP
PROCUCT
TANK
RECIRCULATION
PUMP
FIGURE 4: PROCESS FLOW DIAGRAM FOR LABORATORY RESEARCH UNIT (LRU)
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RESULTS AND DISCUSSION
Literature Review and Glassware Tests
RCC obtained and evaluated the available chemical data on the waste
stream from the Chiyoda Flue Gas Desulfurization Process. The purpose of
this evaluation was to develop the procedure for the glassware testing and to
obtain initial indications of evaporator performance when concentrating the
scrubber waste water.
Available chemical data were received on the composition of wastes
from the Chiyoda installation at Sneads, Florida. The data, all of which are
presented in Appendix B, covered the time period from March 1975 thru May 1976
and included composition of limestone neutralized waste water which was the
feed to the RCC evaporator (Table Bl). The waste water is a mixture of the
mother liquor purge (Table B2) and prescrubber blowdown (Table B3) which has
been neutralized with limestone. Analysis of the data revealed that high con-
centration factors were possible with this waste because the low TDS and high
ratio of calcium sulfate to other salts would yield a concentrate with a low
boiling point rise and a high seed level.
Laboratory glassware tests were performed on a sample of the limestone
neutralized waste water from the Chiyoda liquid waste pond at the Sneads,
Florida facility.
The as received sample was analyzed for the chemical and physical pro-
perties. The analytical procedure used to determine the chemical properties
of the waste water processed in this demonstration program are summarized in
Table 1. The results of these analyses are presented in Table 2. The chemical
composition of the sample was found to be similar to earlier waste compositions
reported in the data received from Chiyoda.
In the glassware tests, the Chiyoda waste water sample was concentrated
77.5 times by volume resulting in a suspended solids level of 129,312 mg/1.
The suspended solids contained 84.7% CaSCL, the evaporation proceeded smoothly
and the analysis of the dissolved solids (TDS 50,474 mg/1) indicated that
further concentration was possible without significantly changing the composition
12
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TABLE 1: Summary of Analytical Procedures*
Calcium - titration with standard EDTA solution
Magnesium - titration with standard EDTA solution
Chloride - titration with silver nitrate solution
Sulfate - precipitation with barium chloride
Bicarbonate - titration with standard acid
Nitrate - Brucine Method
Silica - colorimetric method with ammonium molybdate
Sulfite - titration with potassium iodide-potassium iodate
Fluoride - Alizarin visual method
Iron - colorimetric method with mercapto-acetic acid
*Further discussion of these procedures can be found in 'Standard Methods
for the Examination of Water and Wastewater' Fourteenth Edition.
13
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TABLE 2: Results of Glassware Analyses
PARAMETER
pH
Specific Gravity at 60°F
TDS at 220°F
TDS at 900°F
Suspended Solids
Sodium (Calc.)
Calcium
Magnesium
Chloride
Sulfate
Bicarbonate
Si 1 ica
Sulfite
Nitrate
Iron
Total (Calc.)
Total Organic Carbon
Total Inorganic Carbon
Boiling Point
Specific Heat
Viscosity
Specific Conductance
FEED
7.00
1.003
3,200 mg/1
2,800 "
11.8
148 mg/1
680 "
92 "
40 "
2,000 "
122 "
4 "
2 "
189 "
0.16
3,277.16 mg/1
CONCENTRATE
(77. 5X)
6.10
1.042
54,550
33,650
129,312
5,975
600
5,569
3,099
20,756
73
100
2
14,300
0
50,474
4
19
99. 8° C G> 99
3.906 X 103
0.4177 X 10
mg/1
n
n
mg/1
ii
ii
M
ii
n
ii
ii
it
n
mg/1
mg/1
.7 kPa
J/kg '
-3Pas
DISTILLATE
6.88
% OF SALT REMOVED
FROM SOLUTION
0.25 mg/1
47.9
98.9
21.9
0.0
86.6
99.2
67.7
98.7
2.3
100
80.1
5.854 micromhos/cm
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of the suspended solids.
The glassware results showed the Chiyoda waste to be of composition
similar to brines presently being processed in commercial RCC evaporators.
The waste is saturated with calcium sulfate and thus requires pretreatment
with a small amount of scale inhibitor to prevent fouling of the feed heat
exchanger and deaerator as the feed is heated prior to entering the evapor-
ator. Based on chemical composition of the feed and the results of the glass-
ware boildown, it was concluded that the waste could be concentrated up to
about 100 times and still remain within process limits of the evaporator.
Bench Model Tests
The Bench Model Evaporator testing was conducted at the RCC Laboratory
in Seattle, Washington between September 2 and September 16, 1976.
The purpose of the Bench Model Evaporator test was to verify glassware
predictions and to establish the operating conditions for the on-site demon-
stration tests to be conducted with the LRU pilot evaporator. The Bench
Model Evaporator was operated at two concentration levels, 37.5X and 128X.
The results of the tests indicated that the feed can be concentrated at least
100X and a high quality distillate can be produced from the ponded Chiyoda
waste. The Bench Model Evaporator test confirmed predictions made from the
glassware test data.
At the beginning of the first bench model test the evaporator sump was
filled with waste water at a pH of 6 and gypsum was added to provide the
necessary seed level. After a period of heat soak, steam was then introduced
into the heat transfer panel and a stable concentration of 37.5X was reached
after about 3 days. The concentration was maintained for the remainder of the
8 day run. During the bench model testing the feed was acidified with sulfuric
acid to aid in decarbonation. Scale inhibitor was also added at a rate of 15
ppm to prevent fouling of the heat exchanger and deaerator. Foaming of the
circulating brine was encountered at the beginning of the test, but subsided
as the sump concentration increased. No addition of an antifoaming agent was
necessary.
15
-------
The distillate was of excellent quality during the first run except
when solids carry over was encountered due to the initial foaming. Phys-
ical and chemical properties of the feed, concentrate and distillate for
the first run are presented in Table 3.
Operating data for the first concentration run are presented in
Figures 5 and 6. The evaporator was operated at an average heat transfer
delta T of 4.1°C (7.3°F). The heat transfer coefficient (U value) plotted
in Figure 5 is seen to vary between 3.07 and 4.20 kW/m2 °K (540-740 BTU/
hr ft °F). The boiling point rise (B.P.R.) was essentially constant
throughout the test at about 0.56°C (1.0°F).
At completion of the run the evaporator was disassembled, inspected
and cleaned. The heat transfer surfaces were found to be clean and in
general the unit appeared "as new". A photograph of the heat transfer panel
after the first run is presented in Figure 7. The white spots on the heat
transfer panel is where seed has gathered in areas of pitting corrosion
encountered in a previous test program.
The second concentration run was made following the same procedure
except that the initial seed level was 140 g/1. A concentration factor of
128X was reached in approximately 5 days and was maintained for 4 days.
Results of the analysis of the feed concentrate and distillate are pre-
sented in Table 4. The operating data pertaining to the second concen-
tration run are presented in Figures 8 and 9. The evaporator was oper-
ated at an average heat transfer delta T of 3.9°C (7.0°F). The heat
transfer coefficient (U value) plotted in Figure 8 varied from 3.29 to
4.26 kW/m2 °K (580-750 BTU/hr ft2 °F).
The evaporator was disassembled and inspected at the completion of
this test. The heat transfer panel was slightly fouled with calcium sul-
fate as shown in Figure 10. The fouling was observed when the circulating
brine flow was reduced resulting in incomplete wetting of the heat trans-
fer panel. The reduced flow was caused by the increased viscosity and
density of the brine at the abnormally high concentration factors attained
16
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TABLE 3; Bench Model Evaporator - Run #1 Analyses
PARAMETER
PH
Specific Gravity at 60°F
TDS G> 220°F
TDS g 900°F
Suspended Solids
Sodium
Calcium
Magnesium
Chloride
Sulfate
Bicarbonate
Silica
Sulfite •
Nitrate
Iron
Fluoride
TOTAL (Calc.)
Total Organic Carbon
Total Inorganic Carbon
Boil ing Point
FEED
6.7
1.006
3,190 mg/1
2,690 "
0 "
138 mg/1
656 "
97 "
43 "
1,939 "
110 "
4 "
2 "
174 "
0.16 "
18 "
3,181.16 mg/1
7 mg/1
20 "
372. 6°K (<> 99.6 kPa
CONCENTRATE
(37. 5X)
6.75
1.024
30,050 mg/1
17,450 ".
89,732 "
1,268 mg/1
640 "
3,742 "
1,937
10,125 "
146 . "
14 "
2 "
7,436 "
0 "
2 "
25,312 mg/1
30 mg/1
20 "
372. 9°K @ 99.6 kPa
DISTILLATE
8.2
2.67
Specific Heat
Viscosity
Specific Conductance
3.91 X 103 J/Kg °K
0.41 X 10"3 Pas
% OF SALT REMOVED
FROM SOLUTION
75.5
97.4
86.1
96.5
90.7
97.3
**
100
99.7
78.8%
8.029 micromhos/cm
* Inaccuracy of this determination is believed to be caused by the interference of .heavy metals
** This discrepency is believed to be a result of experimental error in the analytical technique used to
measure the nitrate concentration.
-------
TABLE 4: Bench Model Evaporator - Run #2 Analyses
oo
PARAMETER
PH
SpeciYic Gravity at 60°F
TDS P 220°F
TDS @ 900°F
Suspended Solids
Sodium (Calc.)
Calcium
Magnesium
Chloride
Sulfate
Bicarbonate
Silica
Sulfite •
Nitrate
Iron
Fluoride
Total (Calc.)
Total Organic Carbon
Total Inorganic Carbon
Boiling Point
Specific Heat
Viscosity
Specific Conductance
FEED
7.57
1.005
3,210 mg/1
2,680 "
0 "
152 mg/1
664 "
83 "
47 "
1,912 "
122 "
7 "
2 "
186 "
0.18 "
7 "
3,182.18 mg/1
1 mg/1
21 mg/1
372. 8°K G> 98.9 kPa
CONCENTRATE
(128X)
6.7
1.070
101,250 mg/1
57,650 ".
309,436 "
2,859 mg/1
720 "
13,851 "
5,423 "
34,438 "
159 "
149 "
2 "
24,596 "
0 "
275 "
82,472 mg/1
99 mg/1
15 mg/1
373. 0°K G> 98.
352 X 103 J/k
0.45 X 10"3 P
DISTILLATE
5.7
5.0 mg/1
% OF SALT REMOVED
FROM SOLUTION
84.5
99.2
*
9.9
85.9
99.0
83.7
99.2
**
0
69.3
79.8
3.6295 micromhos/cm
* Inaccuracy of this determination is believed to be caused by the interference of heavy metals in the
measurement of magnesium concentration.
** This discrepency is believed to be a result of experimental error in the analytical technique used to
measure the nitrate concentration.
-------
U VALUE.kW/m2*K
».35
3.98
3.41
2.84
2.41
2.27
1.70
1.14
0.57
FEED PUMP —
FAILED
^
«
,^
>— -
' <
*^
—
y
M
<
— L(
11 o
• ••»-
)W FE
:D
'©*£><
-CLEANED COOL
WATER LINE
ING
%
t- -.
(
-»
bo
BPR « . °C
A T B . °C
5.56
5.0
4.44
3.89
3.33
2.78
2.22
1.67
1.11
0.56
0
« 16 24
8-27-76 I
8 16
8-28
24
8 16
8-29
24
8 16
8-30
24
8 16
8-31
24
I
8 16 24
9-1 I
3 16 24
9-2 I
8 16
9-3
24
FIGURE 5: BENCH MODEL TEST RESULTS - RUN #
(Heat Transfer Data)
-------
ro
o
IZ
11
10
9
8
7
SU»>TDS«X 10"4. mg/1 f
0
SIMP SSQX10"4. man
4
3
2
1
0
8
FEED pH • 7
DI5T. pH 0 6
SUMP pH A
5
4
- — •
• 1
4 8 16 2
8-30
/
LEANE
ATER
. <
\
D C0(
1 INF
^^
^
LING
O—
r
X
II
1 \
\
d>
k
•e —
j
. <
1
b
KD^s,
/
I
1 —
/
^
. *
MD
S3
_— J
C
^.^
)— n
(
4 8 16 24 8 16 2
8-31 1 9-1
(
b-~^I
_. — C
-1
)
)
4 8 16 24 8 16 2
9-2 | 9-3
FIGURE 6 : BENCH MODEL TEST RESULTS - RUN #1
lOperating Data)
-------
Figure 7. Heat Transfer Panel After Run Number 1
-------
4.SS
3.58
3.41
2.34
U VALUE. 2.27
kW/m2eK 1.70
1.14
0.57
0
ro
PO
BPRo. °C 2,
1.
1.
0
8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24
9-11-76 I 9-12 I 9-13 I 9-14 I 9-15 I 9-16 I 9-17 | 9-18 I 9-19 I
8 16 24
9-20 I
FIGURE 8: BENCH MODEL TEST RESULT - RUN #2
(Heat Transfer Data)
-------
JOOZ72
26
24
22
20
16
16
14
12
10
8
TWO
X 10"4. nig/1 6
. mg/1
OiST. pH e
CONC. pH O
TEED pH A
j_
8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24 8 16 24
9-11-76 I 9-12 I 9-13 I 9-14 I 9-15 I 9-16 I 9-17 I 9-18 I .9-19 I 9-20 I
FIGURE 9: BENCH MODEL TEST RESULTS - RUN #2
(Operating Data)
-------
' )
Figure 10. Heat Transfer After Run Number 2
-------
during the test. The deposit observed is not expected to occur in commer-
cial RCC evaporators because complete wetting of the tubular heat transfer
surfaces is assured by equipment design and accurate control of the brine
flow. There was a deposit of solids in the mist eliminator (Figure 11).
The mist eliminator wash system in the commercial RCC evaporators would
have removed this deposit; however, the bench model evaporator does not
have this capability.
On-Site Demonstration Tests
The Laboratory Research Unit (LRU) pilot evaporator was installed on-
site at the Sneads, Florida facility and took its feed from the Chiyoda
liquid waste pond containing the neutralized waste from the Chiyoda FGD
Process. The pilot unit was operated 60 days to insure successful demon-
stration of the technical objectives and obtain sufficient data to support
operating and capital cost estimates for a full scale system. The primary
objective of this test was to demonstrate the long term performance of the
RCC falling film, vapor compression evaporator when concentrating the
Chiyoda FGD Process waste water.
Results of the on-site demonstration tests indicate that the waste
water volumes can be reduced to less than 1% of the present volume and a
high quality distillate would be produced from the ponded Chiyoda waste
water.
Prior to start-up, an analysis of the liquid pond indicated that the
composition had changed significantly from the feed used in the bench
model evaporator tests. This change in pond composition was caused by the
incorrect use of dolomitic limestone for neutralization. After the use of
dolomitic limestone was discontinued, the pond was drained and refilled
with fresh waste water. Analyses of the refilled pond indicated that the
composition was still different from the bench model evaporator test feed.
Therefore, the initial operating conditions for the LRU were modified and
the concentration factor estimated from the bench model test data (115X)
had to be revised to approximately 70X.
25
-------
HIRE MESH MIST ELIMINATOR
CM
1
I
I
^
a
I
•sa
e
26
-------
On startup, the LRU was seeded and the concentration level was in-
creased to a concentration factor of about 70X. This concentration level
was maintained for about 33 days to establish stable operation. Then the
suspended solids level in the sump was increased slowly to about 250 g/1.
At this suspended solids level, analysis of the solids indicated that the
precipitating species included the double salt, Vanhoffite (S^SO.-MgSOJ.
Although no immediate problems were encountered, the concentration factor
was reduced because the long term effects of double salt formation are
unknown. The concentration factors attained during the on-site demonstra-
tion are presented in Figure 12. The concentration factors are also pre-
sented in tabular form in Appendix C.
The feed to the evaporator was analyzed daily for total solids (TS)
and a complete chemical analysis was performed weekly. Results of these
analyses are presented in Figure 13 and Table 5, respectively. The analyses
indicated that the feed is saturated with CaSO,. The important chemical
constituents in the feed were calcium sulfate (CaSOj, silica (SiOo), and
bicarbonate ion (HC03~). The calcium sulfate and silica are potential
hard scale formers and require a scale control process when the feed is
concentrated in the evaporator. The presence of the bicarbonate ion re-
quires that acid pretreatment be used to permit deaeration and decarbona-
tion in the deaerator for removal of non-condensible gases. During the test
period the feed was acidified with sulfuric acid (H-SO.) in the feed tank
where a scale inhibitor was also added. The pH of the feed was adjusted
as necessary to produce a sump pH of 6.5 to 7.1. The feed was then pre-
heated, deaerated and decarbonated prior to evaporation. When steady oper-
3
ating conditions were reached, the feed rate was approximately 265 cm /D
(4.2 gpm).
The sump brine was analyzed several times daily for total dissolved
solids (TDS) and suspended solids (SS). This data is presented in Figure
13. An analysis of the sump brine was performed each week during the test
period. The results of these analyses are summarized in Table 6. The
brine did exhibit a tendency to foam periodically during the test, but was
27
-------
150-
125-
o
< fe
u. 2
O LU
100--
75--
50"
25 ••
I I I I ' I I I I I I I I I I
t; 9C I K II
5
FEB
15
25
MAR
15
25
APR
DATE OF OPERATION
FIGURE 12: WASTE VOLUME REDUCTION DURING ON-SITE TEST
28
-------
TABLE 5: Chemical and Physical Properties of Evaporator Feed
SAMPLE NO.
DATE
PH
SP. GR.
70S (200°F)
70S (900°F)
SS (mg/1)
Na (calc)
Ca (mg/1)
Mg
txj
vo Cl
SO, -
HC03
Si02 "
Fe
N03 "
F
SO,
1769
1/30
7.45
1.006
4,700
3,830
10
528
280
316
91
2,835
85
12
0.11
277
25
0
1771
1/31
7.35
1.006
4,830
3,990
10
407
320
316
91
2,754
110
12
0.09
256
19
0
1797
2/3
7.90
1.006
4,920
4,020
11
426
560
316
76
3,330
73
14
0
256
18
0
1807
2/7
7.59
1.004
4,360
3,820
12
376
480
292
91
2,900
85
14
0.13
256
9
0
1816
2/9
6.95
1.006
4,520
3,680
12
197
560
292
73
2,750
73
17
0
256
9
0
1820
2/11
7.3
1.008
4,440
3,600
12
581
440
170
73
2,800
49
15
0.37
256
18
0
1839
2/15
7.00
1,010
4,270
3,450
8
122
580
243
85
2,450
49
15
0.26
246
16
0
1850
2/18
6.45
1.007
4,350
3,510
10
345
600
231
86
2,900
67
14
0.42
256
17
0
1899
2/25
6.38
1.005
4,060
' 3,350.
12
111
580
207
30
2,349
61
16
0
277
14
0
1917
3/4
6.5
1.007
3,990
3,270
TR.
334
560
122
76
2,430
49
15
0.21
256
18
0
1970
3/11
7.2
1.005
4.100
3,280
0
332
600
170
67
2,390
85
14
0.24
328
13
0.5
1997
3/18
6.15
1.007
3,790
3,140
0
195
400
194
79
2,106
37
9
0.18
389
8
1
2026
3/26
6.4
1.007
4,300
3 3,10
0
1,485
480
292
66
3.645
49
9
0.32
410
12
4.5
-------
TABLE 6: Chemical and Physical Properties of Sump Concentrate
SAMPLE NO.
DATE
Cone. Factor*
PH
Sp. Gr.
TDS (220°F)
TDS (900°F)
SS
B.P. (°C)
GO @ kPa
o
Na (calc)
Ca (mg/1)
Mg
Cl "
so4 "
HC03 "
Si02 "
F
N03 "
so3 "
Fe
1770
1/30
26
4.95
1.022
20,880
15,130
102,930
99.8
99.8
216
560
2,381
498
10,530
37
125
1772
1/31
37
4.93
1.053
41,040
30,150
137,628
99.9
99.8
194
1,000
4,374
1,012
21,465
61
200
1798
2/3
52
6.30
1.093
119,500
87,800
136,332
100.6
100.3
233
500
18,529
3,776
70,000
98
325
200
19,680
0
0
1808
2/7
80
6.70
1.127
166,750
121,300
182,040
101.1
100.3
233
550
21,080
4,834
78,750
171
79
284
29,725
1816
2/9
72
6.70
1.121
166,200
114,100
157,170
101.0
99.9
3,004
500
22,478
4,834
90,000
122
81
284
27,470
1821
2/11
77
6.60
1.119
150,650
107,450
192,030
100.8
99.9
4,838
480
20,048
5,136
83,750
98
82
208
28,495
1840
2/15
73
6.70
1.115
142,550
102,100
175,998
100.2
99.5
•1,872
550
19,258
4,836
75,000
98
86
1851
2/18
57
6.75
1.C98
133,200
90,050
116,846
100.2
99.4
1,872
500
19,470
' 4,924
75,574
134
87
210
26,445
0
0
1900
2/25
64
6.95
' 1.081
113,000
73,650
147,126
100.3
100.3
1,588
480
13,498
4,909
51,250
134
72
152
24,395
0
1
1918
3/4
77
6.59
1.094
129,550
78,600
178,992
100.0
99.5
1,701
800
14,197
2,266
58,663
134
79
256
31,160
0
0
1971
3/11
94
6.45
1.114
162,300
99,600
222,638
100.0
99.3
11,989
800
19,562
6,646
65,813
159
77
248
37,517
0
0
1998
3/18
111
6.40
1.115
164,700
101,350
254,856
99.9
99.4
12,256
750
18,377
7,250
57,713
195
26
244
•41,410
0
0
2027
3/26
76
6.88
1.108
153,150
84,500
214,874
99.8
98.4
6,820
1,000
19,076
7,175
55,688
207
37
220
33,825
0
0
* Based on Total Solids
-------
TO/SJ
X 10~*. ng/1
ISO-
so-
10.000
nto rs
•9/1
^
FEB HAft APR
1977
FIGURE 13: ON-SITE DEMONSTRATION TEST OPERATING DATA
-------
easily eliminated with the intermittent use of an antifoaming agent. The
distillate produced during the test was of excellent quality being gener-
ally in the range of 0.25 to 9.33 mg/1 IDS. The specific conductance of
the distillate remained below 16 micromhos/cm throughout the test program.
Results of the distillate analyses are presented in Table 7.
The heat transfer data obtained during the on site tests is presented
in Figure 14. The evaporator was operated at an average heat transfer
delta T of 1.7°C (3.0°F). The heat transfer coefficient (U) varied from
3.29 to 5.11 kW/m2 °K (580 to 900 BTU/hr ft2 °F) and averaged about 4.15
kW/m2 °K (730 BTU/hr ft2 °F). The boiling point rise (B.P.R.) was between
0.8°C (1.5°F) and i.,<°c (3.3°F) throughout the testing.
Inspection of the evaporator at the completion of the test revealed
a deposit on the evaporator sump walls and on the exterior of the inlet
brine nozzles in the floodbox. The deposit was a result of the equipment
shutdown procedure and was not caused by insufficient action of the scale
control mechanism. The heat transfer tubes contained no detectable deposit.
32
-------
TABLE 7: Properties of the Product Water From
Evaporator
SAMPLE NO.
DATE
1822
2/11
1852
2/18
1901
2/25
1919
3/4
1972
3/11
1999
3/18
2028
3/26
2043
4/1
PH
8.00
5.78
7.20
7.60
7.60
6.88
5.70
6.02
Snec. Cond.
Qjmhos/cm)
9.529
16.14
5.417
13.182
11.770
5.859
5.650
4.794
TDS G> 220UF
mg/1
3.70
2.67
4.33
9.33
3.33
3.33
0.25 .
4.24
33
-------
5.68
3.41-
i.ZJ
3.89
/
/
/
OCITA T.
2.78-
1.60-
JM
' I l' ' '4' ' '7 10 1J 16 19
' FEB
' '25' ' '28| I ' '41 ' '?' ' 'lO1 ' '13' ' 'le' ' 'l9'
' OM.
1977
' '25' ' '281 ' "Jill1
FIGURE 14: ON-SITE DEMONSTRATION TEST HEAT TRANSFER DATA
-------
SECTION 5
DESIGN CONDITIONS FOR FULL SCALE SYSTEMS
The following design conditions for a process to concentrate the waste
water from Chiyoda Flue Gas Scrubber have been established. These condi-
tions are based on the results of the demonstration test program, informa-
tion obtained from Chiyoda regarding the composition of the waste stream
from their process and Resources Conservation Co.'s previous experience
concentrating similar waste streams.
Feed Chemistry
The composition of the Chiyoda FGD Process waste stream to be concen-
trated in the full scale evaporator is presented in Table 8. At the Sneads
facility, Chiyoda diluted the acidic waste water 2 1/2 times prior to
neutralization to facilitate pumping. Therefore, to calculate the compo-
sition of the waste stream presented in Table 8, the acidic waste water was
neutralized with limestone and corrected for the supersaturation of CaSO,.
The composition of the acidic waste was based on the operating experience
of Chiyoda at Sneads.
Pretreatment Requirements
The feed must be acidified with sulfuric acid to a pH of 6 to aid in
bicarbonate removal. Scale inhibitor (i.e. Nalco 345) must be added to the
feed at a rate of 15 ppm to prevent fouling of the heat exchanger and
deaerator. Antifoam agent (i.e. Dow Corning DB110) may be required peri-
odically to control foaming.
Overall Heat Transfer Coefficient (U)
The overall heat transfer coefficient used to size the evaporator will
be 3.18 kW/m2 °K (560 BTU/hr ft2 °F). This value is based on the results
35
-------
of the demonstration test program, interpretation of the test data with
2
the Duckler correlations for heat transfer in vertical tubes and previ-
3
ous experience of RCC with similar waste streams.
Heat Transfer Delta T
The evaporator will operate at a heat transfer delta T of up to 5°C
Concentration Factor
The nominal waste streams composition presented in Table 8 will be
concentrated 112X. The range of concentration possible will be 44X to
122X depending on the waste stream composition. The waste volume will be
reduced to about 1% of its initial volume. The composition of the concen-
trated waste stream from the evaporator is given in Table 9.
Energy Consumption
The predicted energy consumption for concentrating the nominal com-
position waste is 26.7 kWh/m (101 kWh/1000 gal). The energy consumption
will be 24.3 to 29.3 kWh/m3 (92 to 111 kWh/1000 gal) over the range of
expected waste compositions.
Distillate Quality
Water recovered from the Chiyoda waste stream will be excellent quality
(less than 10 ppm TDS). This is sufficient quality for boiler make up,
which results in a definite savings in demineral izer regeneration time and
chemicals.
2) Duckler, A. T., "Fluid Mechanics and Heat Transfer in Vertical Falling-
Film Systems", Chemical Engineering Progress Symposium Series, Vol.56,
No.30.
3) H. Herrigel, T. Fosberg, W. Stickney and C. Perry, "Operating Data of
a Vertical Plane Surface, Falling Film Evaporator Using Slurry and
* High Concentration Feeds", OSW Report 14-30-2939, Office of Saline Water,
October 1972.
36
-------
TABLE 8: Composition of Neutralized Chiyoda Waste Stream
ANALYSIS
Sodium
Calcium
Magnesium
Chloride
Sulfate
Silica
Nitrate
Fluoride
Sulfite
IDS (calc.)
TABLE 9: Composition
ANALYSIS
Sodium
Calcium
Magnesium
Chloride
Sulfate
Sil ica
Nitrate
Fluoride
Sulfite
TDS (calc.)
NOMINAL CONCENTRATION
345 mg/1
530 "
370 "
585 "
2337 "
18 "
750 "
.15 "
8 "
4958 "
of Concentrated Waste Stream from
NOMINAL CONCENTRATION
54744 mg/1
494 "
41440 "
53328 "
120661 "
200 "
84000 "
1680 "
896 "
352354
37
RANGE
220 - 1250
390 - 586
243 - 991
100 - 1212
2088 - 4596
5 - 26
435 - 1652
9 - 25
0 - 13
3586 - 10251
Evaporator
RANGE
26766 - 57684
329 - 543
29646 - 43604
12200 - 65520
113931 - 161886
200
.53070 - 90100
1100 - 1830
0 - 1586
237242 -369636
-------
SECTION 6
ECONOMICS
This section presents an estimate of the capital and operating costs for
providing full scale treatment of the flue gas desulfurization waste stream.
A schematic of the waste treatment process is presented in Figure 15. The
design conditions given in the previous section was used to properly size the
required process equipment.
The capital and operating costs are presented in a manner that permits an
estimate to be calculated for a range of waste water flowrates to the waste
treatment process. Capital costs for the waste treatment process are presented
in Figure 16. The capital cost includes all process equipment and accessories
installed at the site, but does not include cost of land and buildings. The
operating costs of the waste treatment process are presented in Figure 17.
The operating costs are presented for treating the range of waste stream compo-
sitions given in the previous section. The operating costs include power at
2c/kWh, maintenance materials, operation and maintenance labor and pretreatment
chemicals. The amortization of capital is not included in the operating costs.
The operating cost of the FGD waste treatment process is somewhat lower
when credit is given for the high quality water recovered from the waste stream.
When the reclaimed water is used for boiler makeup, the operating costs of the
boiler water polishing ion exchange system is significantly reduced. For exam-
ple, when reclaimed water (less than 10 ppm TDS) replaces well water (500 ppm
TDS), the operating cost of a 378.5 m3/D (100,000 gpd), 2 bed ion exchange sys-
tem with degasifier is reduced about $0.40 to $0.46/m3 ($1.50 to $1.75/1000 gal).
38
-------
XXX
ACID
FEED
FEED
TANK
PUMP
PRODUCT'
...J
VENT
i
x
>T*~ HEAT "
~* — EXCHANGER "*
i
1
D
E
A
E
R
A
T
0
1 F
DEMISTER
FEED
X-o
BOILER
PUMP
STEAM
s\ —
1
i
BOILER
PRODUCT
WATER
STEAM COMPRESSOR SYSTEM
PRODUCT
TANK
RECIRCULATION
PUMP
WASTE
PUMP
FIGURE 15: RCC BRINE' CONCENTRATOR
PROCESS FLOW DIAGRAM - SCHEMATIC
— PRODUCT
— STEAM
— FEED
— RECIRCULATION BRINE
.- WASTE BRINE
-------
3000
2500
2000
o 1500
o
CO
1000
500
i i i i
500
1000 1500 2000 2500 3000
PLANT CAPACITY - m3/D
FIGURE 16: CAPITAL COST FOR WASTE TREATMENT SYSTEM
3500
4000
-------
140
120
100
o
UJ
00
00
UJ
o
CL.
60
40
20
NOMINAL IDS LEVFI
LOW TDS LElvFI I WASTE
OF
WATER
500
1000 1500 2000 2500 3000 3500
PLANT CAPACITY - m3/D
FIGURE 17 - OPERATING COST FOR WASTE TREATMENT SYSTEM
4000
-------
APPENDIX A: TEST EQUIPMENT
BENCH MODEL EVAPORATOR
The bench model testing was conducted using the RCC vertical flat plate,
falling film, bench model test evaporator. Feed enters through a condensate/
feed heat exchanger, steam heat exchanger and deaerator. Evaporation occurs
as the concentrate flows in a film over the outer surfaces of a 15 cm wide x
2
92 cm high x 4 cm deep hollow panel which provides 0.186 m of heat transfer
surface area. The heat transfer surface thickness is 0.66 mm. Plant steam,
fed to the inside of the panel through a pressure regulator, is used as the
heat source for evaporation. The steam formed from evaporation of the concen-
trate is condensed and flows out of the system through the feed heat exchanger.
View ports are provided for observation of the heat transfer panel during oper-
ation. The evaporator body, piping and heat transfer panel are constructed of
Type 316 stainless steel.
Controls are provided for automatic operation of the unit. The control
system consists of a level controller which provides on-off control of the feed
pump. Also, a timer-operated valve is provided to control the discharge rate
of concentrate and thereby maintain sump concentration.
Feed and evaporator temperatures are continuously monitored on a multi-
point recorder. A calibrated thermometer is installed in the sump to measure
the boiling point of the concentrate. Pressures are measured periodically with
water manometers and gauges. Total dissolved solids are determined by weighing
samples and drying at 104.4°C (220°F).
The flat plate evaporator was selected for this test since the heat trans-
fer surface is exposed for inspection during test operation. The fluid film
which is formed on the flat surface has essentially the same flow characteris-
tics as the vertical tubes used in RCC evaporator and thus gives heat transfer
and process data applicable to the commercial plant.
42
-------
LABORATORY RESEARCH UNIT
The on-site demonstration tests were conducted with the RCC Laboratory
Research Unit (LRU). The LRU is a 22.7 m3/D (6000 gal/D) vertical tube,
falling film, vapor compression, pilot evaporator, designed to simulate the
operation of a commercial size RCC unit. The LRU is fully instrumented to
measure and record process data. Level and pressure controls permit automatic,
unattended operation. Materials of construction include 304 stainless steel
tubes, 316 stainless steel sump, titanium feed heat exchangers, and fiberglas
and 316 stainless steel piping.
The waste to be processed is fed through feed filters to the feed tank.
Sulfuric acid is added for bicarbonate ion removal. The feed tank provides
a short residence time for complete acidification before the feed is pumped
to the heat exchangers where its temperature is raised close to boiling. From
there it is fed to an electrically heated hot surge tank where the feed is
raised to slightly above its boiling temperature. The feed then enters the
deaerator, flashes to remove non-condensibles and is then fed to the evaporator
sump where it is concentrated.
The concentrated brine slurry in the sump is recirculated down the inside
of the condenser tubes in a thin film with a small amount evaporated as steam.
This steam is collected and then compressed to raise its temperature of con-
densation slightly above the boiling point of the brine on the inside of the
tubes. The steam condenses on the outside of the tubes and causes more steam
to be evaporated from the brine inside the tubes. The condensate is collected
as product, water and pumped back through the heat exchanger to recover its
heat.
The small concentrated slurry waste stream is taken from the recirculation
line and is discharged periodically through a timer operated control valve.
Scale control is accomplished by utilizing a seed slurry method which pre-
vents scale deposition on metal surfaces by providing preferential sites within
the waste brine for crystal growth.
43
-------
APPENDIX B: CHIYODA WASTE WATER CHEMISTRY
TABLE Bl CHIYODA LIQUID PURGE SETTLING POND OVERFLOW ANALYSIS
DETERMINED CONCENTRATION (mg/1)
PARAMETER
TDS
TSS
pH (en site)
Temperature °C
Total Calcium as Ca
Total Magnesium as Mg
Total Sodium as Na
Total Potassium as K
Total Hardness as
Total Phosphorus as P
Dissolved Silica as S
Sulfate as $04
Sulfite as S03
Carbonate as CaC03
Bicarbonate as CaC03
Hydroxide as CaC03
Chloride as Cl
DATE
7 17/75
''640
6
2.31
20
750
140
e;.o
:.93
2670
j.036
3-J.8
2750
<1
0
0
0
138
8/25/75
2000
6
2.60
26
330
39
58
0.85
1093
<0.01
22
1160
<1
0
0
0
55
9/29/75
3360
393
4.10
16
675
83
65
2.4
2055
<0.01
16-
1910
<1
0
3.3
0
75
10/27/75
4670
9
7.53
24
860
182
34
1.0
2900
<0.01
12
2570
<1
0
38
0
51
11/18/75
4994
88
6.75
21
1100
144
50
2.8
3360
0.01
22
2460
<1
0
8.1
0
77
12/22/75
4338
238
4.55
18
726
246
28
2.3
2871
<0.01
24
2008
<1
0
0
0
97
1/26/76
8180
826
10.80
18
614
90
2320
13
1920
0.014
3.4
3590
22.4
965
566
0
168
2/23/76 3/29/76
5640
19
6.75
13
996
300
164
4.6
3740
0.015
20
0
_, 2500
<1
o 0
25
0
460
4/26/76
4580
17
3.88
20
370
142
616 .
5.4
1542
0.026
20
2600
<1
0
0
0
182
5/26/76
6730
7
6.22
24
426
172
1270
14
1780
0.020
15
3900
0
0
9.5
0
213
-------
TABLE Bl CHIYODA LIQUID PURGE SETTLING POND OVERFLOW ANALYSIS (cont'd)
DETERMINED CONCENTRATION (mg/1)
PARAMETER
DATE 7/17/75 8/25/75 9/29/75 10/27/75 11/18/75 12/22/75 1/26/76 2/23/76 3/29/76 4/26/76 5/26/76
Total Aluminum as Al
Total Arserr.c as As
Boron as B
Total Cadmium as Cd
Total Chromium as Cr
Total Copper as Cu
Total Iron as Fe
Total Lead as Pb
Total Manganese as Mn
Total Mercury as Mg
Total Nickel as Ni
Total Selenium as Se
Total Zinc as Zn
Oil and Grease
Nitrate as N
Chemical Oxygen Demand,
(COD)
4.16
<0.01
4.6
-
0.04
0.06
109.0
<0.01
0.68
0.006S
0.10
C.083
1.3
. 76
11
3.5
<0.01
1.0
-
<0.01
0.16
50
<0.01
0.17
0.0022
0.020
0.016
0.26
20
<1
2.1
<0.01
2.0
-
<0.01
0.076
7.9
<0.01
0.44
0.0014
0.10
0.033
0.67
45
4.4
0.88
<0.01
2.5
-
<0.01
0.064
2.5
<0.01
0.56
<0.0002
0.020
0.036
0.26
87
<1
3.4
<0.01
3.8
<0.01
<0.01
0.14
0.54
<0.01
0.65
<0.0002
0.042
0.070
0.67
102
6
4.8
<0.01
3.0
<0.01
<0.01
0.30
8.6
<0.01
1.08
0,0006
0.15
0.13
1.1
105
5.7
0.
<0.
2.
<0.
<0.
0.
6.
<0.
0.
0.
0.
0.
0.
88
01
9
01
01
il
8
01
21 3
0018
_J
078 u.
58
089 =
27
23
2.
<0.
3.
<0.
<0.
0.
0.
<0.
1.
<0.
0.
0.
0.
<
1
01
8
01
01
044
90
01
2
0002
16
10
74
.1
•I
115
20
3.4
<0.01
6.0
0.012
<0.01
0.24
7.1
<0.01
0.77
<0.0020
0.16
0.045
0.53
72
22
1.7
<0.01
3.9
<0.01
<0.01
0.083
0.45
<0.01
0.74
0.0005
0.067
0.026
0.39
68
15
-------
TABLE Bl CHIYODA LIQUID PURGE SETTLING POND OVERFLOW ANALYSIS (cont'd)
DETERMINED CONCENTRATION (mg/1)
PARAMETER
DATE 7/17/75 8/25/75 9/29/75 10/27/75 11/18/75 12/22/75 1/26/76 2/23/76 3/29/76 4/26/76 5/26/76
Carbon Dioxide as C0£
Total Acidity as CaC03
Color es Pt. Co. Units
(True)
Turbidity as NTU's
Fluoride as F
970
1080
6
12
27
466
432
13
4.2
4.2
50
51
13
92
16
25
0
3
16
16
28
20
0.5
11
26
62
64
3
65
26
0
0
2
450
12.1
3
O
_l
u.
0
z
32
0
0.5
21
20
46
61
1
21
8.2
20
21
0.5
4.5
10
-£»
CT>
-------
TABLE B2 CHIYODA PRESCRUBBER SLOWDOWN ANALYSIS
Suspended Total Specific
H2SO. Cl" Total Fe NH. NO " Ca Mg Solids Dissolved Gravity
Date % (ppm) (ppm) (pprfi) (ppfl) (ppm) (ppm) (ppm) Solids
(ppm)
3/4/75
3/5/75
3/5/75
3/5/75
3/6/75
3/6/75
3/7/75
3/7/75
3/8/75
3/8/75
3/9/75
3/10/75
3/10/75
3/11/75
3/11/75
3/20/75
3/27/75
3/28/75
3/30/75
3/31/75
4/1/75
4/1/75
4/2/75
4/3/75
4/15/75
4/16/75
4/17/75
4/18/75
4/21/75
4/22/75
4/23/75
5/12/75
0.09
0.13
0.06
0.04
0.05
0.06
0.14
0.02
0.10
0.00
0.08
0.07
0.07
0.09
0.08
0.11
0.08
0.08
0.10
0.05
0.03
0.08
0.01
0.00
0.00
0.00
885.1
3130.
1547.
1446.
1284.
1671.
2431.
914.8
470.6
1198.
1246.
1166.
275.9
575.3
368.9
224.1
465.4
425.8
501.9
556.6
734.
991.6
769.5
628.6
591.
552.6
449.
586.0
1061.
17.24
22.31
19.3
337.9
261.
25.
18.
20.
15.
2.92 57.97
3.1 49.6
68.2
57.4 294.
End Start-up
-------
TABLE B2 CHIYODA PRESCRUBBER SLOWDOWN ANALYSIS (cont'd)
00
Date
CT
(ppm)
Beain Test Schedule
5/!i/75
£/::'./75
5/^/75
5 T/75
5-7-I/75
5'li/75
6'2/75
6/3/75
6/4/75
6/5/75
6/6/75
6/9/75
6/10/75
6/11/75
6/12/75
6/13/75
6/16/75
6/17/75
6/18/75
6/19/75
6 '20/75
6/23/75
6/24/75
6/25/75
6/26/75
6/27/75
0.03
0.09
0.21
0.22
0.22
0.00
0.10
0.09
0.20
0.08
0.05
0.06
0.08
0.13
0.05
0.10
763.4
573.8
509.9
1191.
1239.
1007.
662.1
255.5
35.49
233.2
624.5
221.0
185.5
599.2
248.4
579.9
407.0
675.1
321.3
404.1
1113.
688.9
859.4
249.3
231.6
223.7
Total Fe
(ppm)
,NH4*
(ppm)
NOX"
(ppm)
++
Ca
(ppm)
Mg++
(ppm)
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
1586.
3.1
79.36
18.5
0.0
88.04
75.
52.6
87.2
54.2
24.7
509.
20.
71.
2194.
17.
3944
-------
TABLE B2 CHIYODA PRESCRUBBER SLOWDOWN ANALYSIS (cont'd)
H0SO.
Date
Cl"
(ppm)
7/2/75
7/3/75
7/7/75
7/10/75
7/11/75
7/14/75
7/15/75
7/16/75
7/17/75
7/18/75
7/21/75
7/22/75
7/23/75
7/24/75
7/25/75
7/28/75
7/30/75
7/31/75
8/1/75
9/16/75
9/17/75
9/18/75
9/19/75
9/22/75
9/23/75
9/26/75
9/29/75
9/30/75
0.05
0.08
0.06
0.36
0.25
0.10
0.10
0.10
0.03
0.19
0.10
0.00
0.16
0.07
0.08
0.15
0.13
0.13
0.14
0.12
0.13
0.06
400.1
242.4
53.22
1251.
915. 5
346.9
417.9
481.9
688.9
615.0
463.2
31.54
675.1
264.1
462.2
46.32
467.1
260.2
520.3
187.2
184.3
173.4
250.3
208.9
188.1
198.6
172.0
136.8
Total Fe
(ppm)
(ppm)
NOX"
(ppm)
Ca
(ppm)
Mg
(ppm)
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
6.2
80.6
Undetectable
16.
75.0
65.
28.2
2388.
2784.
177.
170.
148.
-------
en
o
TABLE B2 CHIYODA PRESCRUBDER SLOWDOWN ANALYSIS (cont'd)
. Suspended Total Specific
h'2S04 Cl Total Fe NH. NOX" Ca Mg Solids Dissolved Gravity
% (ppm) (ppm) (ppS) (ppm) (ppm) (ppm) (ppm) Solids
(PPm)
10/1/75 0.07
10/2/75
10/3/75 0.08
10/6/75 0.12
10/7/75
10/P/75 0.09
10/9/75
10/9/75 0.11
10/14/75 0.03
10/15/75 0.06
10/15/75
10/17/75 0.14
10/20/75 0.21
10/20/75 0.24
10/21/75 0.08
10/21/75 0.16
10/22/75 0.09
10/22/75 0.08
10/23/75 0.08
10/23/75 0.08
10/24/75 0.10
10/24/75 0.05
10/27/75 O.iO
10/27/75 0.06
10/28/75 0.07
10/28/75 0.03
10/29/75 0.05
10/29/75 0.03
10/30/75 0.09
10/30/75 0.07
10/31/75 0.06
183.4
252.7
240.4
261.3
267.9
140.0
178.6
165.3
134.9
151.5
245.0
342.0
461.7
184.3
233.5
249.9
214.7
237.5
242.0
225.6
154.3
174.5
141.7
176.5
199.5
244.9
256.5
260.3
282.5
333.6
-------
TABLE B2 CHIYODA PRESCRUBBER SLOWDOWN ANALYSIS (cont'd)
Date
11/3/75
11/4/75
11/5/75
11/6/75
11/7/75
11/10/75
11/11/75
11/12/75
11/13/75
11/14/75
11/17/75
11/18/75
11/19/75
11/20/75
11/21/75
12/1/75
12/2/75
12/3/75
12/4/75
12/5/75
12/8/75
12/10/75
12/11/75
12/12/75
12/15/75
12/16/75
12/16/75
12/23/75
12/30/75
H0SO.
2% 4
0.03
0.06
0.04
0.04
0.12
0.06
0.18
0.19
0.05
0.17
0.14
0.14
0.13
0.08
0.05
0.05
0.04
0.05
0.06
0.15
0.15
0.15
0.14
0.07
cr
(ppm)
211.2
288.3
295.1
319.2
424.3
198.6
485.0
358.7
370.3
388.6
373.2
443
413
310
318
350.0
281.6
257.5
163.9
185.1
157.2
251.7
405.0
300.8
489.8
650.4
650.4
432.0
498.5
Total Fe
(ppm)
++
(ppm)
(ppm)
f
Ca
(ppm)
(ppm)
Suspended
Sol ids
(ppm)
Total
Dissolved
Solids
(ppm)
28.
Specific
Gravity
0.994
0.993
0.992
0.991
0.992
0.992
0.993
0.990
-------
TABLE B2 CHIYODA PRESCRUBBER SLOWDOWN ANALYSIS (cont'd)
tn
r>o
Date
HSO
Cl"
(ppm)
1/2/76
1/5/76
1/9/75
1/12/75
1/14/76
1/19/76
2/26/76
2/27/76
3/1/76
3/2/76
3/3/76
3/5/76
3/8/76
3/10/76
3/12/76
3/15/76
3/17/76
3/22/76
3/24/76
3/26/76
3/29/76
3/31/76
4/2/76
0.11
0.07
0.15
0.12
0.16
0.09
0.38
0.36
0.32
0.11
0.16
0.24
0.25
0.22
0.07
0.14
0.13
0.08
0.10
0.09
0.00
0.06
0.03
551.5
481.1
1161.
580.5
570.8
340.4
588.2
986.4
1164.
568.9
820.6
1667.
1465.
898.7
237.2
815.7
3216.
333.6
1850.
343.3
1813.
2126.
1475.
Total Fe
(ppm)
NH4
(ppm)
NOX"
(ppm)
Ca
(ppm)
Mg
(ppm)
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
0.0
0.0
577.0
-------
TABLE B3 CHIYODA MOTHER LIQUOR ANALYSIS
en
oo
Date
3/3/75
3/7/75
3/7/75
3/8/75
3/R/75
3/10/75
3/10/75
3/11/75
3/11/75
3/11/75
3/12/75
3/25/75
3/28/75
3/30/75
3/31/75
4/1/75
4/1/75
4/2/75
4/3/75
4/14/75
4/15/75
4/16/75
4/17/75
4/18/75
4/21/75
4/22/75
4/23/75
5/12/75
2.1
1.93
1.9
1.88
1.74
1.71
1.65
1.57
1.52
1.30
1.08
--
1.26
1.77
1.79
1.79
1.66
1.58
1.83
0.98
0.47
0.96
1.04
1.11
1.21
0.89
0.85
0.90
Cl"
(ppm)
85.2
132.8
Fe
2416.
NH4
(ppm)
NOX"
(ppm)
Mg
(ppm)
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
153.2 2425.
140.5 2450.
141.1
663.4
End Start-Up
-------
TABLE 83 CHIYODA MOTHER LIQUOR ANALYSIS (cont'd)
en
Date
Begin Test Schedule
5/13/75
5/11/75
5/15/75
5/16/75
5/19/75
5/20/75
5/21/75
6/2/75
6/3/75
6/4/75
6/5/75
6/6/75
6/D/75
6/10/75
6/11/713
6/12/75
6/13/75
6/15/75
6/17/75
6/1S/75
6/19/75
6/20/75
6/23/75
6/24/75
6/25/75
6/26/75
6/27/75
7/2/75
0.96
1.40
1.10
1.43
1.19
1.17
1.09
0.97
0.78
1.10
0.45
1.25
1.58
1.49
1.29
1.20
0.92
0.59
0.85
1.22
1.32
1.18
1.10
1.14
1.34
1.33
1.34
1.10
(ppm)
136.3
124.3
112.9
103.4
88.41
86.58
79.69
79.83
80.02
80.42
78.45
Fe
(ppm)
NOX"
(ppm)
Ca
(ppm)
Mg
(ppm)
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
1880.
1754.
1554.
1539.
1637.
1800.
2056.
2191.
2277.
2351.
904.
837.
743.
870.
975.
1110.
782.
830.
870.
875.
381.
380.
228.
289.
564.
496.
661.
755.
896.
872.
31548.
-------
TABLE B3 CHIYODA MOTHER LIQUOR ANALYSIS (cont'd)
Date
H2,S04
en
01
7/3/75
7/7/75
7/10/75
7/11/75
7/14/75
7/15/75
7/15/75
7/17/75
7/18/75
7/21/75
7/22/75
7/23/75
7/24/75
7/25/75
7/28/75
7/30/75
7/31/75
8/1/75
8/o/75
8/8/75
9/15/75
9/16/75
9/17/75
9/18/75
9/19/75
9/22/75
9/23/75
9/26/75
9/29/75
9/30/75
0.95
1.10
0.77
1.51
1.82
2.44
2.89
3.13
2.91
0.75
0.39
0.67
0.90
1.11
2.55
2.43
2.66
3.09
3.25
1.74
1.26
1.70
1.93
2.31
1.34
1.92
1.63
1.37
1.34
Cl"
(ppm)
74.11
64.06
74.50
81.01
77.86
48.49
r
Te
2223.
2183.
2138.
2149.
2384.
2195.
1816.
2435.
2550.
2114.
1977.
1914.
NH4 NOX" Ca
(ppm) (ppm) '(ppm)
708.
860.
1160.
1007.
1000.
Mg
(ppm)
729.
623.
610.
779.
693.
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
884.
890.
506.
715.
-------
TABLE B3 CHIYODA MOTHER LIQUOR ANALYSIS (cont'd)
Date
cr
(ppm)
Fe
NH4+
(ppm)
NOX~
(ppm)
Ca
(ppm)
Mg
(ppm)
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
10/1/75
10/2/75
10/3/75
10/6/75
10/7/75
iO/3/75
10/9/75
10/14/75
10/15/75
10/16/75
10/17/75
10/20/75
10/21/75
10/22/75
10/23/75
10/24/75
10/27/75
10/28/75
10/29/75
10/30/75
10/31/75
11/3/75
11/4/75
11/5/75
11/6/75
11/7/75
11/10/75
11/11/75
11/12/75
11/13/75
1.31
1.05
0.90
0.97
0.99
1.08
1.07
0.66
0.72
0.90
0.95
0.79
0.87
0.78
0.80
0.86
1.03
1.10
1.13
1.03
0.99
0.93
0.89
1.00
0.96
0.73
1.29
1.45
1.33
1.45
2074.
2223.
2258.
812.
750.
805.
915.
865.
882.
950.
905.
728.
830.
911.
672.
2166.
1060.
481.
1.021
1.022
1.020
1.020
-------
TABLE B3 CHIYODA MOTHER LIQUOR ANALYSIS (cont'd)
en
—i
Date
11/14/75
11/17/75
11/18/75
11/19/75
11/20/75
11/21/75
12/1/75
12/2/75
12/3/75
12/4/75
12/5/75
12/8/75
12/10/75
12/11/75
12/12/75
12/15/75
12.16/75
12/23/75
12/30/75
1/2/76
1/5/76
1/9/76
1/12/76
1/14/76
1/19/76
2/26/76
2/27/76
3/1/76
3/3/76
H9SO,
2% 4
1.21
1.17
1.31
1.11
1.2C
1.04
1.32
1.66
1.58
1.54
1.43
1.19
1.09
1.09
1.22
1.03
1.07
1.84
0.31
0.25
0.62
0.45
0.46
0.41
0.42
0.43
0.91
0.79
0.50
Cl"
(pprn)
41.66
Fe
2172.
2212.
2532.
2550.
2212.
NH4
(ppm)
NOX~
(ppm)
Ca
(ppm)
1004.
975.
1040.
1040.
922.
Mg
(ppm)
681.
570.
760.
841.
829.
Suspended
Solids
(ppm)
Total Specific
Dissolved Gravity
Solids
(ppm)
1.020
1.020
1.019
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TABLE 83 CHIYODA MOTHER LIQUOR ANALYSIS (cont'd)
Date
H SO
3/5/76
3/8/76
3/9/76
3/19/76
3/11/76
3/12/76
3/15/76
3/15/76
3/17/76
3/18/76
3/22/76
3/23/76
3/24/76
3/25/76
3/26/76
3/29/76
3/30/76
3/31/76
4/1/76
4/2/76
0.46
0.06
0.93
0.73
0.97
0.63
0.71
0.49
0.35
0.28
0.65
0.33
1.32
0.99
0.26
0.39
0.49
0.65
0.50
1.09
Cl"
(ppm)
Fe
1891.
2435.
2361.
2493.
NH4+
(ppm)
NOX"
(ppm)
Ca++
(ppm)
M + +
Mg
(ppm)
Suspended
Solids
(ppm)
Total
Dissolved
Solids
(PPM)
Specific
Gravity
-------
APPENDIX C
Waste Volume Reduction During On-Site Tests
DATE CONCENTRATE RATE
(gpm)
2/5/77
2/6/77
2/7/77
2/8/77
2/9/77
2/10/77
2/11/77
2/12/77
2/13/77
2/14/77
2/15/77
2/16/77
2/17/77
2/18/77
2/19/77
2/20/77
2/21/77
2/22/77
2/23/77
2/24/77
2/25/77
2/26/77
2/27/77
2/28/77
3/1/77
3/2/77
3/3/77
0.072
0.060
0.043
0.057
0.056
0.067
0.106
0.065
—
0.065
0.063
0.062
0.062
0.06
0.061
0.064
0.060
0.061
0.059
—
0.864
0.064
0.064
0.054
0.052
0.044
0.030
FEED RATE
(gpm)
3.90
4.05
4.20
4.20
4.15
3.90
4.20
4.00
—
4.00
3.95
4.00
4.15
4.05
4.00
4.15
4.00
4.15
4.20
—
4.10
4.20
4.10
4.20
4.15
4.20
4.10
59
CONCENTRATION FACTOR
(based on volume)
54
67
98
74
74
58
60
62
--
61
63
65
67
66
66
65
67
68
71
--
64
66
64
78
80
95
137
-------
DATE CONCENTRATE RATE
(gpm)
3/4/77
3/5/77
3/6/77
3/7/77
3/8/77
3/9/77
3/10/77
3/11/77
3/12/77
3/13/77
3/14/77
3/15/77
3/16/77
3/18/77
3/18/77
3/18/77
3/19/77
3/20/77
3/21/77
3/22/77
3/23/77
3/24/77
3/25/77
3/26/77
3/27/77
3/28/77
3/29/77
0.035
0.034
0.036
0.032
0.031
0.033
0.035
0.034
0.033
0.034
0.032
0.035
0.037
0.042
0.040
0.043
0.040
0.044
0.045
0.047
0.044
0.043
—
0.042
0.045
0.044
0.045
APPENDIX C
(cont'd)
FEED RATE
(gpm)
4.05
4.00
4.15
4.15
4.00
4.05
4.25
4.25
4.45
4.55
4.45
4.65
4.70
4.70
4.80
4.80
4.80
4.80
4.85
4.50
4.55
4.65
—
4.50
4.60
4.60
4.80
CONCENTRATION FACTOR
(based on volume)
116
118
115
130
129
123
121
125
135
134
139
133
127
112
120
112
120
109
108
96
103
108
—
107
102
105
107
60
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APPENDIX C
(cont'd)
DATE CONCENTRATE RATE FEED RATE CONCENTRATION FACTOR
(gpm) (gpm) (based on volume)
3/30/77 0.043 4.80 112
3/31/77 0.048 4.80 100
4/1/77 0.039 4.40 113
4/2/77 0.043 4.50 105
4/3/77 0.053 4.30 81
4/4/77 0.053 4.50 85
4/5/77 0.052 4.50 86
61
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TECHNICAL REPORT DATA
(Please read /tmnictions on the reverse before completing)
REPORT NO.
EPA-600/7-77-106
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
Effective Control of Secondary Water Pollution from
Flue Gas Desulfurization Systems
5. REPORT DATE
September 1977
6. PERFORMING ORGANIZATION CODE
. AUTHOR(S)
8. PERFORMING ORGANIZATION REPORT NO.
Lanny D. Weimer
9. PERFORMING ORGANIZATION NAME AND ADDRESS
Resources Conservation Company
P.O. Box 936
Renton, Washington 98055
10. PROGRAM ELEMENT NO.
EHE624A
11. CONTRACT/GRANT NO.
68-02-2171
12. SPONSORING AGENCY NAME AND ADDRESS
13. TYPE OF REPORT AND PERIOD COVERED
EPA, Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, NC 27711
Final: 7/76-5/77
14. SPONSORING AGENCY CODE
EPA/600/13
IB. SUPPLEMENTARY NOTES IERL_RTP prOject officer for this report is Fredrick A. Roberts,
Environmental Research Laboratory, Corvallis OR 97330 (420-4715).
16. ABSTRACT
The report describes tests to demonstrate the feasibility of using a vertical-
tube, falling-film, vapor-compression evaporator to concentrate waste water from a
flue gas desulfurization (FGD) process. Tests showed that waste water from the
Chiyoda FGD process can be concentrated up to 140 times and with recovery of more
than 99% of the waste stream as high quality water (< 10 ppm TDS). Two series of
tests were conducted: one with a 25 gpd bench model evaporator; the other with a
6000 gpd pilot size evaporator. Process conditions were identified and verified for
scale free operation. Heat transfer coefficients of 500-750 Btu/hr-sq ft-°F were
consistently achieved throughout the tests. A conceptual design and economic study
of a full size treatment facility showed that capital costs will range from #5110 to
$8706/1000 gpd of waste water processed, depending on system capacity. Operating
costs will vary from $2. 46.to $3.60/1000 gal. of waste water processed, depending
on system capacity and waste water composition. Some credit can be taken for
savings on boiler makeup water treatment costs by providing the high quality
distillate to that process.
17.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.IDENTIFIERS/OPEN ENDED TERMS
c. COSATl Field/Group
Pollution
Waste Water
Water Treatment
Flue Gases
Desulfurization
Distillation
Pollution Control
Stationary Sources
Chiyoda Process
13B
21B
07A,07D
13H
18. DISTRIBUTION STATEMENT
Unlimited
19. SECURITY CLASS (This Report)
Unclassified
21. NO. OF PAGES
62
20. SECURITY CLASS (This page)
Unclassified
22. PRICE
EPA Form 2220-1 (9-73)
62
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