FGD
QUARTERLY
REPORT
INDUSTRIAL
ENVIRONMENTAL
RESEARCH
LABORATORY
VOL. 2 NO. 1
WINTER 1977-78
RESEARCH TRIANGLE PARK, NC 27711
INTRODUCTION
The FGD Quarterly Report is part of a comprehensive
Engineering Application/Information Transfer Program on flue
gas desulfurization (FGD). The program is sponsored by EPA's
Industrial Environmental Research Laboratory, Research Triangle
Park, North Carolina (IERL-RTP). The Report is designed to
meet four objectives: (1) to disseminate information concerning
EPA sponsored and conducted research, development, and
demonstration (RD&D) activities in FGD; (2) to provide progress
updates on selected ongoing contracts; (3) to report final results
of various FGD studies, and (4) to provide interested persons with
sources of more detailed information on FGD.
This issue contains two feature articles. The first reports on the
Interagency FGD Evaluation Study with emphasis on the con-
clusions and recommendations of the Technical Working Group.
The second feature article discusses lERL-RTP's lime/limestone
pilot plant, including major contributions of the plant in the past,
current studies, and plans for future investigations.
The FGD Quarterly Report is distributed, without charge, to
persons who are interested in FGD. Recipients wishing to initiate
or cancel their subscriptions to the FGD Quarterly Report may
do so by contacting the EPA Project Officer or Radian Project
Director named on the last page of this issue. Any changes of
address should also be reported.
INTERAGENCY
FGD EVALUATION STUDY
This study was conducted pursuant to the President's National
Energy Plan in which he proposed conversion from an oil- and
natural gas-based energy system to a coal-based energy system.
The use of flue gas desulfurization (FGD) technology is an in-
tegral part of the President's Plan. The objectives of this study
were; (1) to evaluate existing and proposed FGD technologies to
determine if additional research, development, and demonstration
(RD&D) could accelerate the commercialization and acceptance
of FGD technology, (2) to identify what specific RD&D op-
portunities should receive funding, and (3) to estimate the level of
funding necessary to complete the recommended RD&D ob-
jectives. Advanced FGD technologies were reviewed to determine
if they offered the potential for improving current FGD
technologies or if they offered the potential for a new approach to
FGD.
This study was directed by Richard D. Stern, EPA, IERL-RTP.
To ensure maximum objectivity and incorporate a broad per-
spective, the study utilized three Interagency groups: a Technical
Working Group, an Interagency Steering Panel, and a Liaison
Group. (For additional information on the membership of the
groups, see the Fall 1977 issue of the FGD Quarterly Report.)
The functions of the Technical Working Group were to assist in
developing evaluation criteria, to evaluate the FGD processes and
subsystems, to recommend RD&D opportunities, and to review
study products. The Interagency Steering Panel provided
guidance in approach and methodology, reviewed study products
with emphasis on the final report, and supported study con-
clusions and recommendations. The Liaison Group provided
guidance and comment on the study approach, evaluation
methodology, and conclusions and recommendations.
Ground Rules and Assumptions
The following ground rules and assumptions were used in the
conduct of this study:
The study would be completed in 6 months.
There would be extensive coordination and review within the
Federal government.
Both processes and subsystems would be evaluated.
Processes are defined as complete FGD systems while
subsystems are those parts of FGD processes that could be
used virtually interchangeably in several FGD processes.
Processes and subsystems evaluated would have to be
capable of being commercialized in a time frame competitive
with alternative technologies (by 1985).
Processes and subsystems selected for detailed evaluation in
the study would have to show either economic, environ-
mental, or technological advantages over existing or
developing FGD systems.
Processes and subsystems which have demonstrated and/or
have capability for NOx or fine particulate removal would be
given special consideration.
Conclusions and Recommendations
The Technical Working Group concluded that an increase in
the level of Federal funds for FGD research and development was
warranted. Highest priority was given to development efforts that
would yield near term benefits, such as enhancing or improving
FGD technologies currently applied or well along In development.
A secondary priority was given to processes and subsystems that
would yield somewhat later results.
The following RD&D recommendations were developed by the
Technical Working Group. The RD&D recommendations are
listed in order of priority.
Lime/Limestone Improvements
Mass Transfer Additiues: An extension of current
programs that have focused upon evaluating magnesium as
a mass transfer additive for lime/limestone processes was
recommended. Specific additives to be examined included
both organic and inorganic mass transfer additives such as
adipic acid, calcium chloride, and sodium carbonate. The
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FGD QUARTERLY REPORT/WINTER 1977-78
use of mass transfer additives has the potential for im-
proving the SO| removal ability of lime/limestone systems.
Increasing the sorbent utilization, and decreasing process
costs. Initial efforts should be pilot-scale testing followed by
demonstration in a prototype unit.
Forced Oxidation: EPA has an existing program at
TVA's Shawnee Steam Plant. Pilot testing of two process
variations is currently being conducted. A full-scale
demonstration program was recommended by 1979-1980
which could benefit lime/limestone technology in reducing
sludge disposal problems, thus removing a major en-
vironmental impediment to lime/limestone scrubbing and
increasing its applicability. In addition, a potentially
marketable gypsum product may be produced. Full-scale
demonstration could occur by modifying an existing system
and appears to be the next step in commercializing forced
oxidation technology.
Contactors: Extension of ongoing work on concurrent
scrubbing was recommended. Demonstration of concurrent
scrubbing could significantly reduce cost and complexity of
lime/limestone scrubbing. Extension and expansion of
current programs appears necessary to conclusively answer
operability questions. In addition, testing and demonstration
of the Chiyoda Thoroughbred 121 system was recom-
mended. This system has shown significant cost reduction
compared with conventional limestone scrubbing.
Sludge Disposal: Extension of current sludge disposal
activities to evaluate targe-scale disposal options (fixation,
lining, and ponding) was recommended since sludge
disposal is a major environmental problem in
lime/limestone scrubbing.
Hardware Improvements: Problems with mist
eliminators, reheaters, and stack liners have been the cause
of many current FGD system problems. Additional
development work to improve these components was
recommended as a means of increasing the reliability and
operability of FGD systems.
Sulfur Production With Carbon
RESOX: Although the Electric Power Research In-
stitute (EPRi) is funding a RESOX demonstration program
in Germany to produce sulfur from the Bergbau-Forschung
FGD unit using anthracite coal as the reductant, the
Technical Working Group proposed evaluation of the
RESOX Process in a demonstration-sized facility with feed
from front-end systems other than Bergbau. Evaluation of
coals other than anthracite for use as a reductant was also
recommended.
Atomics International Regeneration: Extension of
the EPRI program to demonstrate and operate the Atomics
International Regeneration System in an integrated mode to
gather data for full scale design and construction was
recommended. RD&D efforts on this system would
demonstrate direct conversion of SO, to sulfur without
reducing gas, plus provide additional design data for the
aqueous carbonate process to be constructed at Niagara
Mohawk under EPA funding.
Continuing Evaluation Effort
It was recommended that funds be set aside for technical and
economic evaluation of processes or subsystems that in the future
may solve problems and offer advantages over current FGD
technology. Study ground rules required consideration only of
technology with near term benefits. This continuing evaluation
effort would assure that future improvements in FGD
technology are given a complete and timely evaluation. In ad-
dition, it would provide a source of funding for Important studies
on critical issues in FGD technology that could be of significant
benefit In directing future RD&D activities.
Magnesia Slurry Scrubbing
Demonstration of sustained sulfaric acid production from a full-
scale system would be beneficial in advancing a technology that
appears to have potential for very high SO, removal. In addition,
demonstrating the ability to produce sulfur directly in the calciner
will significantly enhance process applicability. Both concepts
should be demonstrated and evaluated on a full-scale system.
Limestone Use In Sodium-Based Dual Alkali
Systems
Demonstration of the use of limestone as the regenerant in
ongoing pilot work and extension and modification of the EPA
sponsored demonstration program at Louisville Gas and Electric
to test limestone were recommended. The use of limestone in
dual alkali systems could significantly decrease system operating
costs because limestone is a less expensive raw material than
lime.
Sodium System Waste Handling
Disposal: Tests of concepts for fixation plus other
methods of handling purged or once-through waste
materials from sodium-based systems were recommended.
Developing an economical disposal method could increase
applicability of sodium-based throwaway processes with
decreased environmental impact.
Regeneration: Evaluation of methods for regeneration
of sodium-based system by-products and eventual testing
was recommended. This program has benefits of reducing
operating costs, eliminating handling and disposal of waste
materials, and conserving natural resources.
Application of Low-Btu Gas
Evaluation of the use of coal-derived low-Btu gas in FGD
systems was recommended. This would include feasibility studies
based upon system requirements, as well as programs demon-
strating the use of coal-derived reducing gas to produce sulfur.
The use of coal gasification could eliminate the dependence of
some FGD systems on costly and scarce supplies of natural gas.
Sorption/Steam Stripping
The Technical Working Group recommended extension of work
with sorption/sleam stripping in laboratory studies and pilot test*
to be followed by demonstration at the 60-100 MW level. Design
of a general test facility for the testing of the large number of
concepts currently under consideration would be beneficial. The
sorption/steam stripping concept appears to have potential for
more reliable, lower cost operation than some other regenerable
systems.
DowaTest Facility
A pilot plant program to evaluate feasibility of the Dowa
Process in coal-fired applications was recommended. This
Japanese-developed process, which uses limestone as a
regenerant and produces a marketable quality gypsum by-
product, appears to have significant advantages over current dual
alkali FGD technology. A similar program is, however, currently
being considered by EPRI and the Tennessee Valley Authority.
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FGD QUARTERLY REPORT/WINTER 1977-78
Integrated Cat-Ox
Additional support to demonstrate the Integrated Cat-Ox
System at the 100 MW level was recommended. Development of
the process could have significant benefits both in cost and
process simplification.
SULF-X
An evaluation of the SULF-X Process was recommended in
order to analyze independently the claims of vendors. The
process has potential as a SOx/NO* flue gas treatment process
but the claims have not been evaluated independently. This
evaluation is, however, currently planned by the Department of
Energy.
The Technical Working Group estimated that a total sup-
plemental cost (government plus industry) of approximately $100
million would be required to complete the recommended RD&D
options over the next 4-5 years.
A draft report of the Interagency FGD Evaluation Study has
been submitted to the Interagency Steering Panel for review.
Additional information can be obtained from Richard D. Stern,
(919) 541-2915 or (FTS) 629-2915.
PILOT PLANT IMPROVES
FGD PROCESSES
lERL-RTP's lime/limestone pilot plant has been operating at
EPA's Environmental Research Center in North Carolina since
October 1972. Under the direction of Robert H. Borgwardt, the
pilot plant provides experimental support to the larger prototype
studies at EPA's 10-MVV Shawnee test facility.
The pilot plant has two turbulent contacting absorbers (TCA's)
with a flue gas capacity of 8.5 mVmin each which are
concurrently operated. The uniquely sized scrubbers have 1 per-
cent of the capacity of the Shawnee prototypes and are 1/1000
full scale. Thus, the pilot plant is small enough to permit
material balance studies to be conducted and to allow rapid
alterations of operating conditions to be made. At the same time,
the pilot plant is large enough to yield significant results ap-
plicable to larger systems.
Small-scale experiments at the pilot plant have investigated
some of the major problems associated with the lime/limestone
FGD process. Studies have emphasized the application of these
processes to high sulfur coals by using inlet SO, levels of
3000 ppm. Chloride is normally added to the entering flue gas as
HCI gas to provide concentrations of 3000-5000 ppm in the
scrubbing liquor. Under these conditions, the pilot plant
operations have produced significant information in such areas as
process reliability, limestone utilization, sludge quality, and SO,
removal efficiency.
Unsaturated Mode Increases Process
Reliability
Process reliability in some lime/limestone systems has been
hampered by the problem of calcium sulfate (gypsum) scaling.
Scaling can occur when the scrubbing liquor becomes strongly
supersaturated with gypsum. The unsaturated mode prevents
scaling by avoiding supersaturation of the liquor.
Oxidation of SO, to sulfate in the scrubber is the major
variable affecting the unsaturated mode of operation. Multiple
studies conducted in EPA's pilot plant, at Combustion
Engineering, and at Radian Corporation, investigated the
relationship of oxidation to saturation. Results showed that
saturation occurs when at least 16 mole percent of the absorbed
SO, is oxidized. Below this oxidation level, all of the sulfate can
be purged as a solid solution of CaSO, and CaSO4 without
crystallizing gypsum. This phenomenon is important to scale
control in the concentrated dual alkali system as well as in
lime/limestone systems.
Flue gas normally does not contain enough oxygen to cause
saturation. Excessive oxidation can arise when such factors as
changes in boiler toad or air leakage into the system increase the
flue gas oxyg«n levels. Thus by controlling oxygen concentrations
of incoming flue gas, scaling problems can be minimized, par-
ticularly in systems operating with high sulfur coal.
Additional investigations (at the IERL-RTP pilot plant,
Shawnee, and Louisville Gas and Electric Company) indicated
that the addition of magnesium to the scrubbing liquor promotes
the unsaturated mode of operation in lime scrubbers as well as
increasing the SO, removal efficiency at a given liquid/gas (L/G)
ratio. Similar studies adding magnesium to lime scrubbers at the
Shawnee test facility suggested a new variable. The residence
time of the slurry in the effluent hold tank (F.HT) appeared to
affect the degree of saturation in the scrubbing liquor. Saturation
could be minimized only at an EHT residence time of 5.4
minutes.
The Shawnee findings merited further investigation, especially
since the EHT is a major cost item in lime/limestone FGD
systems. A follow-up test program was conducted at the pilot
plant over a 6 month period in 1977. Results showed that the
unsaturated mode of operation can be achieved in the lime
scrubber with any EHT size as long as oxidation is limited to less
than 16 mole percent SO,. Thus it is possible to maintain system
reliability using smaller cheaper EHTs and tower L/G ratios.
Effluent Hold Tank Design Increases
Limestone Utilization
About 70 percent utilization of the limestone feed Is normally
obtained in SO, scrubbers of current design. Utilization is the
fraction of the limestone that is converted to reaction products in
the scrubber. Improved utilization of limestone reduce* the
amount of waste generated by the process, reduces fouling of the
mist eliminators, and lowers operating costs.
An experimental investigation aimed at increasing limestone
utilization was conducted at the pilot plant in 1975. The ap-
proach was based on modification of the scrubber configuration,
particularly the design of the EHT, to accelerate the reactions
that limit the conversion of limestone.
The pilot plant study showed that the design of the EHT is an
important factor in increasing limestone utilization. Maximum
EHT efficiency requires elimination of slurry backmixing.
Backmixing can be reduced by tubular flow or with multiple
stirred tanks connected in series. Three or four tanks of 2 to 3
minutes residence time each are suitable for scrubbers operating
at 3000 ppm inlet SO, levels.
The pilot plant experimented with a system consisting of three
tanks in series and a TCA tower operating at a 19-cm water
pressure drop. This system achieved 89 percent limestone
utilization with 81 percent SO, removal efficiency when scrubbing
with liquor containing 5 g/liter of chloride and an inlet SO,
concentration of 3000 ppm.
Increased limestone utilizations to 94 percent or more were
obtained by either staging the scrubber or by increasing the
tower pressure drop. At a 30-cm water pressure drop, 8 system
consisting of a single TCA tower and a suitably designed EHT
achieved complete limestone utilization. This system had a 90
percent SO, removal efficiency and yielded an effluent pH of 4.
These pilot plant findings were successfully applied to the
Shawnee test facility. Increased limestone utilization is con-
sidered the pilot plant's most important contribution to the
Shawnee operation. Results there have shown about 8 percent
improvement in utilization at a given SO, removal efficiency.
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FGD QUARTERLY REPORT/WINTER 1977-78
Forced Oxidation Improves Sludge
Properties
The environmental and economic aspects of sludge disposal are
considered a major problem in the application of throwaway
processes. Pilot plant studies have demonstrated that calcium
sulfite sludge can be oxidized to calcium sulfate (gypsum) under
operating conditions anticipated for scrubbers at power plants
burning:high sulfur coals. The principal objectives of forced
oxidation are:
to improve the settling properties of the slurry (gypsum
settles 10 times faster than calcium sulfite and yields a
smaller volume of settled sludge),
to improve the dewatering characteristics of the sludge
(preferably to the extent that it can be disposed of directly
as landfill without chemical fixation), and
to reduce the quantity of total waste produced (based on
EPA test results, reductions of 30-40 percent in total waste
production should be possible when forced oxidation is
combined with dry fly ash collection).
Pilot plant configuration for single-loop forced oxidation tests.
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-------
FGD QUARTERLY REPORT/WINTER 1977-78
The better settling and dewatering characteristics of the
oxidized slurry are attributed to the differences in the size and
shape of the crystals formed. The larger, thicker gypsum crystals
settle faster and form a more compact mass than the smaller flat
plates of calcium sulfite.
Pilot plant investigations during 1976 and 1977 demonstrated
that conversion to gypsum can be accomplished efficiently at
operating conditions that are realistic for full-scale application.
Excellent results were obtained in both two-stage and single-stage
scrubber designs in which the oxidation step is conducted within
the scrubbing loop. Both designs were capable of achieving high
SO, removal efficiencies and high limestone utilization while
completely oxidizing the sludge. Oxidation within the scrubbing
loop has been shown to provide several positive benefits to
scrubber performance, including better control over gypsum
supersaturation and scaling, simplification of chemistry,
reduction of CaSO, saturation, and higher pH of scrubber feed
liquor. As a result of the latter, some improvement in SO,
removal is also observed.
Demonstration of oxidation in a single-stage scrubber is
especially important since it indicates that the process is readily
applicable to systems nova in operation. Single-stage systems are
also favored because of the longer particle retention times, the
neutral pH of the oxidized sludge, and simplification of control.
Experiments at the Shawnee facility have corroborated pilot
plant findings for two-stage scrubbers. The Shawnee system
consisted of a first-stage venturi scrubber and a second-stage
spray tower absorber. Complete oxidation was accomplished in
the venturi, with an overall SO, removal efficiency of 83 percent
and a 96 percent limestone utilization in the two-stage system
while producing a sludge containing 80 percent solids. Forced
oxidation experiments at this facility using a single-stage system
will be undertaken in the future.
At the pilot plant, the key to complete oxidation was shown to
lie in efficient transfer of oxygen from the injected air. This
transfer was maximized in shallow tanks by the use of a jet
aspirator which aerates the holding tank with extremely small
bubbles. Alternatively, the required transfer efficiency could be
obtained with a 5.5-m air-sparged tower. Shawnee experience
indicates that the use of a tower, which combines the functions
of the holding tank and oxidizer, will provide maximum overall
efficiency with minimum operating power. With mechanical
mixing, air feed requirements are only 50 percent greater than
the theoretical minimum for complete oxidation.
The tests also demonstrated that high limestone utilization (85
percent) can be maintained while forcing oxidation to gypsum in
the single stage system. These results were achieved without loss
of SO, removal efficiency and indicate that very high reliability
can be expected in scrubbers of this type.
The forced oxidation experiments have shown that the total
waste produced by a power plant equipped with limestone FGD
scrubbers can be reduced by about 43 percent, compared with
current practice, if forced oxidation is combined with dry fly ash
collection. A sludge filterable to about 80 percent solids can thus
be produced, compared to a maximum 55 percent solids nor-
mally obtained with sulfite sludge. Direct disposal as landfill
should be possible with sludges containing 80 percent or more
solids.
Adipic Acid Improves
SO2 Removal Efficiency
The ability of certain scrubber additives to increase SO,
removal efficiency has been demonstrated. At the Shawnee test
facility, addition of magnesium oxide (MgO) to the scrubbing
liquor dramatically increased the SO, removal efficiency of lime
and limestone scrubbers. The effectiveness of MgO, however, is
reduced by forced oxidation and by the accumulation of chloride
in the scrubbing loop.
Recent studies at the pilot plant have addressed these
problems by experimenting wiih adipic acid as an alternate
additive. Adipic acid acts as a buffer in the scrubbing liquor and
permits increased SO, absorption. Benzoic acid is also a suitable
slurry buffer which has been successfully tested by TVA. The
theoretical basis for the effectiveness of these additives has been
developed by Gary Rochelle at the University of Texas.
During November 1977, adipic acid was added to the single-
stage limestone scrubber which was operating in the spray tower
configuration with forced oxidation and no chloride addition. The
SO, removal efficiency was increased from 70 percent, without
adipic acid, to about 80 percent removal at 2500 ppm adipic acid
and 87 percent removal at 5500 ppm. The scrubber operated at a
L/G of 8.7 liters/m3 during these tests.
Subsequent investigations were conducted during December
1977. The objectives of these studies were:
to observe the effect of adipic acid on the SO, removal ef-
ficiency and limestone utilization in the spray tower while
forcing oxidation in the scrubbing loop,
« to compare the performance of the spray towet with a TCA
using adipic acid, and
* to determine whether chloride interferes with the ef-
fectiveness of adipic acid in enhancing SO, absorption.
Adipic acid increased the removal efficiency of the TCA pilot
scrubber by about 10 percent (from 80 percent to 90 percent
removal) when present at a concentration of 1000 ppm in the
scrubbing liquor. This degree of improvement was maintained at
the 85 percent limestone utilization level required for clean mist
eliminator operation. A given concentration of adipic acid im-
proved the SO, removal efficiency of the TCA.
The increased SO, removal efficiency was achieved with
chloride concentrations averaging 15,000 ppm in the scrubbing
liquor. The effectiveness of adipic acid in the presence of high
concentrations of chloride confirms its special suitability as an
additive to scrubbers operating with forced oxidation. Since the
mechanism by which adipic acid operates is not affected by
forced oxidation, this additive is better suited than MgO for use
in such scrubbers, particularly single-loop systems.
Current Studies and Future Plans
Current efforts at the pilot plant are directed at reducing the
overall fresh water requirements of power plants using the
lime/limestone system by integrating new water treatment
processes such as vapor-compression-evaporation into FGD
systems using forced oxidation. The objective is to maximize
water reuse and minimize discharge of soluble salts either with
sludge or waste water.
In current tests the makeup water is replaced with a solution
simulating cooling tower blowdown liquid. The tests are con-
ducted in a single-stage scrubber operating with forced oxidation.
The cooling tower blowdown is primarily a sodium sulfate
solution which results as water evaporates in the cooling tower
and sodium carbonate is added for softening.
Using the cooling tower blowdown liquid rather than adding
fresh water as makeup will substantially reduce overall water
requirements. This is especially important for scrubbers operating
in the dry Western states.
Future plans at the pilot plant call for continuation of these
promising studies. Additional experiments to be conducted will
involve the dual alkali FGD process. The pilot plant will convert
one of its scrubbers to operate in the sodium-based dual alkali
mode. This system will thus provide experimental support to
EPA's full-scale demonstration of the A. D. Little/Combustion
Equipment Associates dual alkali system at Louisville Gas and
Electric Company's Cane Run Station.
Further information regarding the pilot plant can be obtained
by contacting Robert H. Borgwardt, (919) 541-2234 or (FTS)
629-2234.
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FGD QUARTERLY REPORT/WINTER 1977-78
WELLMAN-LORD/ALLIED CHEMICAL
FGD DEMONSTRATION
Significant problems with boiler No. 11 at Northern Indiana
Public Service Company's D. H. Mitchell Station have limited the
operational experience of the FGD plant through the first 4%
months of the demonstration year. As the summary below shows,
the FGD plant has been down for 89 days out of the first 138
days of the demonstration year, and 75 percent of this downtime
is attributable to problems with boiler No. 11.
Sep Oct Nov Dec Jan Total
Plant Running 3.5 14 22.5 9 0 49
Plant Down
(Boiler Problems) 11.5 11
Plant Down
(FGD Problems)
0
4.5
17 24 66.5
19.5
Literature Assessment Report
An additional task of the study Involves a survey and analysis
of th« literature to assess the current status of stack gas reheat
technology. This report has been completed and Is currently
being reviewed by EPA.
The literature survey and analysis addresses the need for stack
gas reheat by first identifying the effects that FGD processes have
on the physical properties of flue gas. Subsequent potential
problems that occur when scrubbed flue gas is discharged from
the stack are also discussed.
The report considers the actual degree of reheat necessary to
prevent potential problems. Techniques are identified which will
allow a prospective user to estimate the degree of reheat required
at a specific plant site.
The final sections of the report present (1) various reheat
system configurations presently in use or under development, (2)
operating data reported for reheat systems used with com-
mercial-scale FGD processes, and (3) capital and operating costs
for these reheat systems.
The overall stack gas reheat assessment study is about 50
percent completed. Additional information can be obtained from
the EPA/IERL-RTP Project Officer, Ted G. Brna, {919) 541-2683.
Plant Down
(Other Reasons) 0 30 003
Cumulative Days 15 46 76 107 138 138
REPORTS DESCRIBE SIMULTANEOUS
NOx/SO2 CONTROL TECHNOLOGY
For additional information, contact the EPA/IERL-RTP
Project Officer, Wade H. Ponder, (919) 541-2915.
STACK GAS REHEAT
ASSESSMENT STUDY
The use of stack gas reheat is necessary to the operation of
some FGD systems. Reheat vaporizes any scrubbing liquor en-
trained in the gas stream, prevents condensation and acid
rainout, reduces or eliminates a visible plume, and enhances
buoyancy of the stack gas. Radian Corporation, under contract to
IERL-RTP, is conducting a study to analyze and compare various
methods of reheat. The objectives of the study are divided into
six subtasks:
Review of all FGD processes, including differences between
the processes and how they affect the need for reheat.
Calculation of a procedure to determine the amount of
reheat necessary for given FGD processes.
Comparison of different reheat systems and media.
* Estimation of the cost and availability of reheat steam
(material and energy balance around a 500 MW steam
generator).
* Reliability assessment.
Economic assessment.
The first subtask, review of all FGD processes, has been
completed. The remaining subtasks are in progress.
Three reports are available which collectively summarize the
status of simultaneous NOX/SO, control technology. Two of the
reports are oriented toward NOX flue gas treatment technology
but also feature simultaneous NOj/SO! processes.
Japanese Abatement Technology
Summarized
Companion documents on NO,, and SO, control technology in
Japan were recently published by IERL-RTP. The reports,
principally authored by Dr. Jumpei Ando of Chuo University,
Tokyo, Japan, are: "SO| Abatement for Stationary Sources in
Japan" EPA-600/7-77-103a (PB 272 316), and "NO, Abatement
for Stationary Sources in Japan*' EPA-600/7-77-103b
(PB 276 948), September 1977. Both reports address
simultaneous NO,/SO, processes and examine their applications,
performance, economics, major technical problems, develop-
mental status, by-products, and raw materials.
NOX and NOX/SO2 Technical and
Economic Study Underway
The first phase of a technical assessment and economic
evaluation study of NOX and simultaneous NO,/SO, flue gas
treatment processes has been completed. The report, "Technical
Assessment of NO, Removal Processes for Utility Application,"
EPA-600/7-77-127 {PB 276 637), November 1977, gives a
technical evaluation of 48 processes including detailed
description, simplified block flow diagram, current developmental
status, raw material and utility requirements, published
economics, technical and environmental considerations, and
overall advantages and disadvantages of each process. Eight
processes are recommended as candidates for preliminary
economic analysis in the next phase of the study. This analysis
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FGD QUARTERLY REPORT/WINTER 1977-18
will enable one to compare the approximate costs of major types
of processes for highly efficient control of NO, and SO,', i.e. dry
or wet simultaneous NOx/SOt or NOx-only plus FGD. The
second phase of the study is scheduled to be complete in Sep-
tember 1978. The overall study is being performed by the Ten-
nessee Valley Authority and is being cofunded by EPA and the
Electric Power Research Institute.
For additional information on NO, or simultaneous NO,/SO|
flue gas treatment technology, contact J. D. Mobley, (919) 541-
2915.
SURVEY REPORTS AVAILABLE
ON FGD APPLICATIONS
Since 1974, EPA has sponsored publication of a bimonthly
survey of FGD units operating on utility boilers. In 1977, a
quarterly survey of FGD units on industrial boilers was initiated.
The reports have been prepared and distributed by PEDCo En-
vironmental Specialists, Inc.
Data in the reports are supplied voluntarily by utility and in-
dustrial boiler representatives, regulatory personnel, and FGD
system designers, vendors, and suppliers. Information is
presented on the control system design, economics, operating
experience, problems and solutions, waste disposal techniques,
and maintenance practices. The number of operational, under
construction, and planned FGD units is also presented.
These reports will be continued in 1978 but in a different
format. The Initial report of the year will contain background
information and a complete description of the boiler and FGD
facilities. Periodic updates of the reports wilt contain only sup-
plementary information. The updates will be cumulative, so that
it will be necessary only to retain the latest and first issue of the
year to have all available information.
EPA's distribution of the reports (generally one copy per
company) is limited to organizations and individuals indicating a
specific interest in the field of FGD technology. Persons receiving
the reports in the past will continue to receive the reports under
the new format.
The first issues of the reports in 1978 are: "EPA Utility FGD
Survey: December 1977 - January 1978" EPA-600/7-78-051a,
March 1978, Project Officer, N. Kaplan; and "EPA Industrial
Boiler FGD Survey: First Quarter 1978" EPA-600/7-78-052a,
March 1978, Project Officer, J. D. Mobley.
OTHER IERL-RTP QUARTERLY
REPORTS AVAILABLE
Coal Cleaning
A recently initiated report, "Coal Cleaning Review," presents
information on: (1) the assessment of pollution from coal
cleaning, coal transportation, and coal storage, (2) the
development of physical and chemical processes for removing
contaminants from coal, and (3) the development of pollution
control technology for coal preparation processes. To obtain a
free subscription to this quarterly report, send a written request
to: J. D. Kilgroe. MD-61, IERL-RTP, U. S. Environmental
Protection Agency, Research Triangle Park, N. C. 27711.
NOx Control
A quarterly report, "NO, Control Review," is available which
presents detailed information on NO, control technology. The
report features: (1) research and development on combustion
control, (2) research and development on flue gas treatment, (3)
control implementation, (4) alternate concepts, and (5) regulatory
strategy. To obtain a free subscription to this publication, send a
written request to: D. G. Lachapelle, MD-65, 1ERL-RTP, U. S.
Environmental Protection Agency, Research Triangle Park, N. C.
27711.
Synthetic Fuels
The first issue of a periodic report, "Environmental Review of
Synthetic Fuels," has recently been released. The report focuses
on: (1) activities of the EPA contractors, (2) summaries of major
symposia, (3) a calendar of upcoming meetings, and (4) a list of
major publications. To obtain a free subscription to this report,
send a written request to: W. J. Rhodes, MD-61, IERL-RTP,
U. S. Environmental Protection Agency, Research Triangle Park,
N. C. 27711.
Fluidized-Bed Combustion
Another quarterly report, "FBC Environmental Review," will
soon be released. The report will address research and
development activities on: (1) environmental assessment, (2)
control technology development, (3) application studies, and (4)
regulatory considerations. To obtain a free subscription to this
report, send a written request to: D. B. Henschel, MD-61, IERL-
RTP, U. S. Environmental Protection Agency, Research Triangle
Park, N. C. 27711.
FIFTH FGD SYMPOSIUM
The next FGD Symposium is currently being planned for
Spring 1979. Comments are solicited on the overall symposium
and session formats and session topics. In addition, any com-
ments or suggestions regarding the last symposium (November
1977, Hollywood, Florida) would be helpful. You can help us
make the Fifth FGD Symposium the best ever. Please contact
C. J. Chatlynnc,either by telephone (919) 541-2915 or by
letter, with your comments and suggestions.
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FGO QUARTERLY REPORT/WINTER 1977-78
FGD REPORTS AND ABSTRACTS
This section of the FGD Quarterly Report contains abstracts of
recently completed reports relating to flue gas desulfurization.
Each listing includes date of the report. National Technical
Information Service (NTIS) accession number, and EPA Office of
Research and Development number.
Each report with an NTIS number can be ordered from NTIS,
The cost of paper copies varies by page count ($4.00 minimum);
microfiche copies are $3. Payment must accompany order. The
address is: National Technical Information Service
U. S. Department of Commerce
Springfield, Virginia 22161
Reports which do not have an NTIS number are available,
as supplies permit, through IERL-RTP*s Technical Information
Service (T1S). The address is:
W. W. Whelan, MD-64
Technical Information Service
Industrial Environmental Research Laboratory
U. S. Environmental Protection Agency
Research Triangle Park, NC 27711
(919) 541-2216
(FTS) 629-2216
Final Report: Dual Alkali Test and Evaluation
Program: Volume I. Executive Summary
C. R. LaMantia, R. R. Lunt, J. E. Oberholtzer, E. L. Field,
and J. R. Valentine, Arthur D. Little, Inc., Cambridge,
Massachusetts, May 1977. EPA-600/7-77-050a. PB 269 904.
Project Officer: N. Kaplan, IERL-RTP.
Volume 1 of the report is an executive summary of the results of a
three-task program to investigate, characterize, and evaluate the
basic process chemistry and the various operating modes of
sodium-based dual alkali scrubbing processes. The tasks were: I,
laboratory studies at both Arthur D. Little, Inc. (ADL) and IERL-
RTP; II, pilot plant operations in a 0.56 NmVs (1200 sc/m)
system at ADL; and III, a prototype test program on a 20 MW
dual alkali system at Plant Scholz. Dual alkali system operating
modes on high and low sulfur fuel applications investigated in-
cluded: concentrated and dilute dual alkali systems, lime and
limestone regeneration, and slipstream sulfate treatment
schemes. For each mode, the dual alkali process was charac-
terized in terms of SO, removal, chemical consumption,
oxidation, sulfate precipitation and control, waste solids
characteristics, and soluble solids losses.
Laboratory Study of Limestone Regeneration in
Dual Alkali Systems
J. E. Oberholtzer, L. N. Davidson, R. R. Lunt, and S. P.
Spelfenberg, Arthur D. Little, Inc., Cambridge, Massachusetts,
July 1977. EPA-600/7-77-074. PB 272 111. Project Officer: N.
Kaplan, IERL-RTP.
The report describes a series of open- and closed-loop laboratory
bench scale experiments which were carried out to study
parameters which affect the reaction of limestone with dual alkali
flue gas desulfurization system process liquors. It gives details of
several sets of operating conditions which permitted good
limestone utilization to be achieved and product solids with good
dewatering properties to be produced. It discusses the effects of
temperature and soluble magnesium on the behavior of the
regeneration reaction as well as the effects of total sulfur
concentration, ionic strength, acidity of the solutions, and reactor
system configuration. It presents date which suggest that
regenerated liquors may have been unsattirated with respect to
magnesium sulfite as a result of its coprecipitatlon with the
calcium sulfite product solids.
Final Report: Dual Alkali Test and Evaluation
Program; Volume II. Laboratory and Pilot Plant
Programs.
C. R. LaMantia, R. R. Lunt, J. E. Oberholtzer, E. L. Field, and
J. R. Valentine, Arthur D. Little, Inc., Cambridge,
Massachusetts, May 1977. EPA-600/7-77-050b. PB 272 770.
Project Officer; N. Kaplan, IERL-RTP.
See EPA 600/2-76-136a, PB 269 904, for abstract.
Final Report: Dual Alkali Test and Evaluation
Program; Volume HI. Prototype Test Program
Plant Scholz.
C. R. LaMantia, R. R. Lunt, J. E. Oberholtzer, E. L. Field, and
J. R. Valentine, Arthur D. Little, Inc., Cambridge,
Massachusetts, May 1977. EPA-600/7-77-050c. PB 272 109.
Project Officer: N. Kaplan, IERL-RTP.
See EPA-600/7-77-050a, PB 269 904 , for abstract.
Project Manual for Full Scale Dual Alkali
Demonstration at Louisville Gas and Electric
Company Preliminary Design and Cost Estimate.
R. P. VanNess, R. C. Somers, T. Frank, J. M. Lysaght, I. L.
Jashnani, R. R. Lunt, and C. R. LaMantia, Louisville Gas and
Electric Company, Louisville, Kentucky, January 1978. EPA-
600/7-78-010. Project Officer: N. Kaplan, IERL-RTP.
The report is the project manual for the dual alkali system,
designed by Combustion Equipment Associates, Inc./Arthur D.
Little, Inc., and being installed to control SO, emissions from
Louisville Gas and Electric Company's Cane Run Unit No. 6
boiler. The project consists of four phases: (1) preliminary design
and cost estimates; (2) engineering design, construction, and
mechanical testing; (3) startup and performance testing; and
(4) 1 year operation and testing. Developed as part of Phase 1,
the project manual includes a detailed description of the dual
alkali process chemistry, the design of the demonstration system
at LG&E, material and energy balances for the system,
specifications of major equipment items and offsites, and capital
and operating costs. Costs for this application have been
generalized for new applications on 500 and 1000 MW high-sulfur
coal-fired boilers.
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FGD QUARTERLY REPORT/WINTER t977-78
TVA's 1-MW Pilot Plant: Final Report on High
Velocity Scrubbing and Vertical Duct Mist
Elimination
G, Hoillnden, R. Robards, N. Moore, T. Kelso and R. Cole,
TVA, Power Research Staff, Chattanooga, Tennessee, and
TVA, Office of Agricultural and Chemical Development, Muscle
Shoals, Alabama, March 1977. EPA-600/7-77-019. PB 269-
850. Project Officer: J. E. Williams, IERL-RTP.
The report describes the systematic test program that led to the
development of washing techniques that maintain continuous
mist eliminator performance for lime/limestone closed-loop
scrubbing systems. TVA recently demonstrated the techniques at
its 1-MW pilot plant at the Colbert Power Plant. The report also
describes high-velocity scrubbing tests performed in conjunction
with the mist eliminator tests. Continuous operation of the
chevron mist eliminator, positioned horizontally in a vertical
duct, in the limestone system was maintained (after extensive
testing at 3.8 m/sec (12.6 ft/sec) by washing the bottom of the
mist eliminator intermittently with all the available clarified
liquor, immediately followed by an allocated amount of makeup
water. The top of the mist eliminator was washed intermittently
with the remaining allocation of allowable makeup water. At a
gas velocity of 4.9 m/sec (16 ft/sec), the scrubber operated more
efficiently and mist eliminator performance was improved.
Continuous mist eliminator performance in the lime system was
maintained at 3.8 and 4.9 m/sec (12.5 and 16 ft/sec) by washing
the bottom of the mist eliminator intermittently with an allocated
amount of allowable makeup water. The remainder of the
allocated makeup water was used to intermittently wash the top
of the mist eliminator.
Flue Gas Desulfurization Using Fly Ash Alkali
Derived from Western Coals
H. M. Ness, E. A. Sondreal, F. Y. Murad (Combustion
Equipment Associates), and K. S. Vig (Square Butte Electric
Co-op), U. S. Energy Research and Development
Administration, Grand Forks, North Dakota, July 1977. EPA-
600/7-77-075. PB 270 572. Project Officer: N. Kaplan, IERL-
RTP.
The report gives results of tests investigating the use of Western
coal fly ash for scrubbing SO, from power plant flue gas, on a
0.06 NmVs (130-scfm) pilot scrubber at the Grand Forks (ND)
Energy Research Center and on a 2.4 NmVs (5000-acfm) pilot
scrubber at the Milton R. Young Generating Station (Center,
ND). Tests of the 0.06 NmVs (130-scfm) unit were designed to
investigate the effects of increased sodium concentration on SOi
removal and rate of scaling. Parameters investigated included
!iquid-to-gas ratios (L/G), stoichiometric ratios (CaO/SO,) and
sodium concentration. Results indicate increased SOj removal
and decreased rate of scaling as sodium concentration increases.
Tests of the 2.4 NmVs (5000 acfm) unit generated design and
operating data for a full-scale 450 MW fly ash alkali scrubber to
be constructed at the same station. Results indicate that suf-
ficient Sd can be removed to meet NSPS requirements, using
only fly ash alkali when burning 0.75% sulfur lignite. An 8-week
reliability test was also performed. Fly ash alkali scrubbing tests
of flue gas SO» were also performed, using a subbituminous-
derived fly ash and other various lignite-derived fly ashes. A
detailed analysis is presented of capital investment and operating
costs for 100, 500, and 1000 MW scrubbers using the fly ash
alkali process.
Economics of Disposal of Lime/Limestone
Scrubbing Wastes: Untreated and Chemically
Treated Wastes.
J. W. Barrier, H. L. Faucett, and L. J. Henson, Tennessee Valley
Authority, Muscle Shoals, Alabama, February 1978. EPA-600/7-
78-023a. Project Officer: J. W. Jones, IERL-RTP.
The report gives results of a comparative economic evaluation of
four alternatives to electric utilities for flue gas desulfurization
(FGD) systems. The alternatives are untreated sludge (pond or
landfill) and sludge chemically treated by commercial processes
offered by Dravo (pond and landfill), 1U Conversion Systems
(landfill), and Chemflx (landfill). The base case for each alter-
native is a new 500 MW power plant burning coal (3.5% sulfur,
16% ash) using a limestone scrubber to meet New Source
Performance Standards for fly ash and SO,. A total of 121 system
design and operating variables were examined for the alternative
processes. Investment and revenue requirements vary con-
siderably for the 121 cases. Capital Investments range from
$10,717,000 ($21.4/kW) to $24,114,000 ($48.2/kW) for the four
base cases; annual revenue requirements for the base cases are
between $3,280,000 (0.94 mills kWh) and $6,988,000 {2.00
mills/kWh). (The capital investment for the base-case FGD
system without sludge dewatering and disposal is $36,368,000
[$7.27/kW]; annual revenue requirements are $11,841,500 [3.38
mills kWh].) The most economical alternative is a function of
site-specific variables such as plant size, remaining life, land
costs, and coal analysis.
EPA Alkali Scrubbing Test Facility:
Advanced Program: Third Progress Report.
Harlan N. Head, Bechtet Corporation, San Francisco, California,
September 1977. EPA-600/7-77-105. PB 274 544. Project
Officer: J. E. Williams, IERL-RTP.
The report gives results of advanced testing from February
through November 1976 of 30,000 acfm (10 MW equivalent)
lime/limestone wet scrubbers for SO, and paniculate removal at
TVA's Shawnee Power Station. Short-term factorial tests (6-8
hours each) with lime, limestone, and Hmestone/MgO were
conducted on both systems to determine SO, removal as a
function of operating parameters. Longer tests (averaging 190
hours each) were conducted on the venturi/spray tower with lime
and lirne/MgO. both with and without % ash in the flue gas. On
the turbulent contact absorber, longer tests (averaging 180 hours
each) were conducted with Hmestone/MgO, lime, and lime/MgO
on flue gas containing fly ash. Adding MgO improved SO,
removal but, in some cases, created a scaling problem. On the
venturi/spray tower, particulate mass loading, site distribution,
and sulfuric acid mist were measured as a function of operating
conditions. Mathematical models fitted to the Shawnee data are
presented for predicting SO, removal as a function of operating
parameters. A simplified procedure is presented for calculating
gypsum saturation from analytical data.
Precipitation Chemistry of Magnesium Sulfite
Hydrates in Magnesium Oxide Scrubbing
P. S. Lowell, F. B. Meserole, and T. B. Parsons, Radian
Corporation. Austin, Texas, September 1977. EPA-600/7-77-109.
Project Officer: C. J. Chatlynne, IERL-RTP.
Laboratory studies were done to define the precipitation
chemistry of magnesium sulfite hydrates. The results are ap-
plicable to the design of magnesium-based scrubbing processes
for SO, removal from combustion flue gas. In magnesium-based
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FDD QUARTERLY REPORT/WINTER 1977-78
scrubbing processes, magnesium sulflte precipitates as either the
trihydrate or the hexahydrate. Equipment design and conditions
depend on which hydrate is formed. Theoretical predictions that
were verified experimentally indicated that MgSO, trihydrate is
the thermodynamicatly stable hydrate formed at scrubbing
process conditions. MgSOj hexahydrate is formed as a
metastable solid due to kinetic phenomena. Nucleation and
crystal growth rates are much faster for hexahydrate than for
trihydrate. The time scales observed in kinetic experiments at
scrubbing process conditions are: hexahydrate precipitation (tens
of minutes), hexahydrate dissolution and trihydrate precipitation
(hundreds of minutes), and attainment of trihydrate equilibrium
(thousands of minutes). Nucleation plays a dominant role in the
formation of trihydrate solids. These results indicate that
magnesium-based scrubbing processes can be designed to
precipitate a majority of either hydrate form. Important design
variables include scrubbing liquor composition and temperature,
seed crystal composition, slurry volume, equipment residence
times, and energy inputs to the slurry that influence nucleation.
Magnesia FGD Process Testing On A Coal-Fired
Power Plant
Diane K. Sornmerer, York Research Corporation, Stamford,
Connecticut, August 1977. EPA-600/2-77-165. PB 272 952.
Project Officer: C. J. Chatlynne, IERL-RTP.
The report gives results of a field measurement program to
determine the operability of the Chemico magnesium oxide
venturi scrubber operating at Potomac Electric Power Company's
Dickerson Generating Station, Frederick, MD. A continuous
source-monitoring station was installed at the scrubber, com-
plemented by a field analytical laboratory intended for the
measurement and analysis of various process streams. These
facilities continuously monitored process and emission variables
between October 1974 and January 1975 and during August
1975. Scrubber operation was evaluated during steady-state and
transient operation, the latter including startups, shutdowns, and
malfunctions. During the tests, the scrubber was available about
48% of the time, including all levels of operation. Approximately
80% of system availability was steady-state, with the system
operating normally. The test showed that, although scrubber
availability was not ideal (due to logistics problems in supplying
raw materials (MgO), and to mechanical problems mainly at-
tributable to under-design in such areas as piping, slurry pumps,
and other auxiliary equipment), the basic scrubber content and
design should meet critical criteria once these problems are
eliminated.
Magnesia Scrubbing Applied to a Coal-Fired Power
Plant.
George Koehler, Chemico Air Pollution Control Company, New
York, New York, March 1977. EPA-600/7-77-018. PB 226 228.
Project Officer: C. J. Chatlynne, IERL-RTP.
The report gives results of a full-size demonstration of the
magnesia wet-scrubbing system for flue gas desulfurization (FGD)
on a coal-fired boiler. The system was designed to desulfurize
half the flue gas from a 190-MW rated capacity generating unit
firing 3.5% sulfur coal. The FGD installation was equipped with a
first-stage wet scrubber for particle emissions control, followed by
the magnesia unit. The FGD system was able to remove 90% of
the SO, over 2,800 hours of operation logged at the generating
station. Its particle control capability was also demonstrated by
reducing particle emissions to less than 0.02 g/Nm' (0.01 gr/scf)
with the unit operated in series with an electrostatic precipitator.
A test program, using only the wet-scrubbing unit for particle
emissions control, achieved a collection efficiency of 99.6%.
Magnesia was regenerated and recycled successfully. The SO,
produced during regeneration was used to manufacture com-
mercial grade sulfuric acid which was marketed. Correlations
were developed to determine SOj removal for varying boiler loads
and fuel sulfur content, and to control regeneration of acceptable
alkali. Several other studies of the process technology and
process chemistry were undertaken as part of the work.
Ammonia Absorption/Ammonium Bisulfate
Regeneration Pilot Plant for Flue Gas
Desulfurization
P. C. Williamson and E. J. Puschaver, Tennessee Valley
Authority, Muscle Shoals, Alabama, August 1977. EPA-600/2-
77-149. PB 272 304. Project Officer: W. H. Ponder, IERL-RTP.
The report gives results of a pilot-plant study of the ammonia
absorption/ammonium bisulfate regeneration process for
removing SO, from the stack gas of coal-fired power plants. Data
were developed on the effects of such operating variables in the
absorption of SO, by ammoniacal liquor as: temperature and
flyash content of inlet flue gas, pH of recirculating absorber
liquor, and oxidation of sulflte to sulfate in absorber liquor. An
equation was developed for operating conditions that should
prevent plume formation in the absorber; however, consistent
ptumeless pilot-plant operation was not achieved. Acidulating and
stripping equipment and operating conditions were developed for
recovering 99 + % of the SO, in the absorber product liquor as a
gas of suitable concentration for processing to sulfuric acid or
elemental sulfur. The proposed study of electrical decomposition
of ammonium sulfate to recover ammonia and ammonium
bisulfate for recycling was not undertaken because of indicated
high energy requirements and unfavorable economics. It is
recommended that any further work involving SO, removal with
ammonia be directed toward a noncyclic process with production
of ammonium sulfate.
Demonstration of Wellman-Lord/Allied Chemical
FGD Technology: Boiler Operating Characteristics
R. C. Adams, T. E. Eggleston, J. L. Haslbeck, R. C. Jordan
and Ellen Pulaski, TRW, Inc., Vienna, Virginia, February 1977.
EPA-600/7-77-014. PB 269 885. Project Officer: W. H. Ponder,
IERL-RTP.
The report gives results of an intensive examination and
characterization of a coal-fired boiler prior to retrofit of a full
scale flue gas desulfurization (FGD) unit employing the Wellman-
Lord/Allied process. The test established a baseline profile of the
boiler for later comparison both with design and operating
conditions of other boilers for which the Wellman-Lord/Allied
process is potentially applicable, and with operating performance
after retrofit of the FGD unit. It also established a baseline profile
during operation of the boiler at conditions other than normal
which have the potential for affecting the performance of the
Wellman-Lord/Allied FGD unit. Boiler operating performance
was examined for its economic performance, overall energy
balance, and the performance of auxiliaries. Detailed profiles of
the flue gas at the proposed boiler/FGD unit interface were
determined at varying boiler control settings including operation
at below normal sulfur, higher than normal flue gas volumes, and
higher than normal grain loadings. The tests were performed on
Boiler No. 11 of Northern Indiana Public Service Company's
Mitchell Power Station.
10
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FGD QUARTERLY REPORT/WINTER 1977-78
SO, Abatement for Stationary Sources in Japan.
J. Ando and B. A. Laseke, PEDCo Environmental, Inc.,
Cincinnati, Ohio, September 1977. EPA-600/7-77-103a, PB 272-
986. Project Officer: J. D. Mobley, IERL-RTP.
The report describes the status of SO, abatement technology for
stationary sources in Japan as of June 1976. It presents the
current status of desulfurization technologies including
hydrodesulfurtzarion of oil, decomposition of residual oil,
gasification of coal and oil, and flue gas desulfurization (FGD). It
examines the major Japanese FGD processes with respect to
their applications, performance, economics, major technical
problems, developmental status, by-products, and raw materials.
It also contains background information on energy usage, fuel
resources, ambient concentration of pollutants, and emission
regulations in Japan. It describes processes for the simultaneous
removal of SO» and NO« from flue gases. It presents a com-
parative evaluation of flue gas cleaning technologies in the
United States and Japan.
The Status of Flue Gas Desulfurization Applications
in the United States: A Technological Assessment.
Report in Full.
Federal Power Commission, Washington, D. C., July 1977. PB-
271 362/6GA.
The report presents a historical survey of the research,
development, and demonstration of flue gas desulfurization
(FGD). The costs of installing, operating, and maintaining FGD
systems are examined. The report discusses alternative
technologies for meeting air pollution control regulations, in-
cluding the use of low sulfur coal and coalwashing, sup-
plementary control systems and tall stacks, solvent refined coal,
coal gasification, and fluldized-bed combustion. The report
compares the cost of FGD with present and future alternatives. It
analyzes the chemistry and equipment used in FGD systems
currently in full scale commercial application. The report presents
the results of a survey of FGD systems in planning stages, under
construction, and operating, and discusses eight discontinued,
full scale scrubber applications in detail.
EPA PROJECT OFFICERS FOR CURRENT FGD RD&D PROJECTS
Robert H. Borgwardt, MD-65
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919) 541-2234
(FTS) 629-2234
Ted G. Brna, MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919) 541-2683
(FTS) 629-2683
C. J. Chatiynne, MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919) 541-2915
(FTS) 629-2915
Julian W. Jones, MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919) 541-2489
(FTS) 629-2489
Norman Kaplan. MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919) 541-2556
(FTS) 629-2556
Robert E. Landreth
USEPA, MERL-Cinn
26 West St. Claire St.
Cincinnati, OH 45268
Phone: (513)684-7871
(FTS) 684-7871
J. David Mobley, MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919)541-2915
(FTS) 629-2915
Michael C. Osborne, MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919) 541-2898
(FTS) 629-2898
Warren D. Peters, MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919) 541-2915
(FTS) 629-2915
Wade H. Ponder, MD-61
USEPA, IERL-RTP
Research Triangle Park, NC 27711
Phone: (919)541-2915
(FTS) 629-2915
Michael H. Rouiier
USEPA, MERL-Cinn
26 West St. Claire St.
Cincinnati, OH 45268
Phone: (513) 684-7871
(FTS) 684-7871
Donald E. Sanning
USEPA, MERL-Cinn
26 West St. Claire St.
Cincinnati, OH 45268
Phone: (513)684-7871
(FTS) 684-7871
John E. Williams, MD-61
USEPA, IERL-RTP
Research Triangle Park. NC 27711
Phone: (919) 541-2483
(FTS) 629-2483
The FGD Quarterly Report is prepared by Radian Corporation under EPA Contract No. 68-02-2608. The EPA Project Officer is J. David
Mobley (address above). The Radian Project Director is Charles E. Hudak, P. O. Box 9948, Austin, Texas 78766, (512) 454-4797. The
Radian Task Director for preparation of this issue is Elizabeth D. Gibson. Comments on this issue, suggested topics for inclusion in future
issues, and requests for subscriptions should be addressed to them.
The views expressed in the FGD Quarterly Report do not necessarily reflect the views and policies of the Environmental Protection
Agency. Mention of trade names or commercial products does not constitute an endorsement or recommendation for use by EPA.
11
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ENVIRONMENTAL PROTECTION AGENCY
Office of Research and Development
Industrial Environmental Research Laboratory
Research Triangle Park, N, C. 27711
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OFFICIAL BUSINESS
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