EPA-600/2-76-085
March 1976 Environmental Protection Technology Series
/C0II BHO-eYll SYSTIi FOR
ELECTRIC POWER GENERATION
Office of Energy, Minerals, and Industry
Office of Research and Development
U.S. Environmental Protection Agency
Washington, U.C, 204SO
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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 five series.
These five broad categories were established to facilitate further
development and application of environmental technology. Elimination
of traditional grouping was consciously planned to foster technology
transfer and a maximum interface in related fields. The five series
are:
1. Environmental Health Effects Research
2. Environmental Protection Technology
3. Ecological Research
4. Environmental Monitoring
5. Socioeconomic Environmental Studies
This report has been assigned to the ENVIRONMENTAL PROTECTION TECH-
NOLOGY series. This series describes research performed to develop
and demonstrate instrumentation, equipment, and methodology to repair
or prevent environmental degradation from point and non-point sources
of pollution. This work provides the new or improved technology
required for the control and treatment of pollution sources to meet
environmental quality standards.
This document is available to the public through the National Tech-
nical Information Service, Springfield, Virginia 22161.
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EPA-600/2-76-085
March 1976
GASIFICATION/COMBINED-CYCLE SYSTEM
FOR ELECTRIC POWER GENERATION
by
J. Bruce Truett
MITRE Corporation
McLean, Virginia 22101
Contract Number 68-01-3188
Task Officer
Gary Foley
Energy Processes Division
Office of Energy, Minerals, and Industry
Washington, D.C 20460
PREPARED FOR
U.S. ENVIRONMENTAL PROTECTION AGENCY
OFFICE OF RESEARCH AND DEVELOPMENT
OFFICE OF ENERGY, MINERALS, AND INDUSTRY
WASHINGTON, D.C. 20460
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DISCLAIMER
This report has been reviewed by the Office of Energy, Minerals, and
Industry, U.S. Environmental Protection Agency, and approved for pub-
lication. Approval does not signify that the contents necessarily
reflect the views and policies of the U.S. Environmental Protection
Agency, nor does mention of trade names or commercial products consti-
tute endorsement or recommendation for use.
ii
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ABSTRACT
This report describes a type of gasification/combined cycle system being
considered for construction by a consortium of Louisiana cities that own
electrical utility systems. The 115 mw system is expected to employ the
Texaco Synthesis Gas Generation Process (TSGGP) to produce a fuel gas by
partial oxidation of a hydrocarbon feedstock. The gas is cleaned to
remove sulfur compounds, ash, and particulates, then burned as fuel for
the gas turbine in a combined-cycle power system.
The commercially-proven TSGGP process accepts a large variety of hydro-
carbons as feedstocks. The initial feedstock for this application is
expected to be heavy petroleum residues, although the potential exists
for utilization of coal and lignite. Other features of the proposed
system include (1) high thermal efficiency (relative to conventional
steam generators) resulting in part from efficient recovery of thermal
energy from the gasification of feedstock; and (2) extremely low levels
of gaseous pollutants (SOX, NOX) in emissions to the atmosphere.
The five participating municipalities have established a joint com-
mission, "Louisiana Municipal Power Commission" (LAMPCO), which has
retained the services of bond counsel and investment banking firms and
is proceeding with plans to implement the proposed power generation
facility.
This report is submitted in fulfillment of Task Assignment Number 14,
Contract 68-01-3188, by The MITRE Corporation under sponsorship of the
U.S. Environmental Protection Agency. The work was completed in Decem-
ber, 1975.
ill
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ACKNOWLEDGEMENTS
The writer is pleased to acknowledge the use of information from tech-
nical reports and other materials made available by personnel of Texaco
Development Corporation and Beard Engineering, Inc., in the preparation
of this report, and to express his gratitude to those who provided this
material. He is especially grateful to Mr. F. B. Sellers of Texaco
Development Corporation and Mr. Harold Beard of Beard Engineering, Inc.,
for their cooperation during preparation of the report. He wishes to
thank the four persons who reviewed the draft report. Their comments
contributed to substantial improvements in the form of presentation and
accuracy of content. Any inaccuracies that may have persisted to the
present version are solely the responsibility of the writer.
iv
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TABLE OF CONTENTS
Page
Abstract iii
Acknowledgement iv
List of Exhibits vii
I INTRODUCTION 1
II SUMMARY 3
III CONCLUSIONS 4
IV RECOMMENDATIONS 5
V OVERVIEW OF THE GASIFICATION/COMBINED-CYCLE SYSTEM 6
SYSTEM DESCRIPTION 6
TYPES OF FUELS 8
ENERGY AND EFFICIENCY RELATIONSHIPS 9
CHARACTERISTICS OF FUEL GAS PRODUCED 10
POLLUTANTS IN WASTE DISCHARGES 10
Nitrogen and Nitrogen Compounds 10
Soot and Unburned Fuel 12
Metals and Metallic Compounds 12
Sulfur and Sulfur Compounds 12
INTEGRATION OF THE GASIFICATION AND COMBINED CYCLE
SUBSYSTEMS 14
DEVELOPMENTAL STATUS OF THE GASIFIER/COMBINED CYCLE
SYSTEM 14
System Cost 15
COMPARISON WITH CAFB PROCESS 16
POTENTIAL OPPORTUNITIES FOR ENVIRONMENTAL R&D;
RECOMMENDATIONS 17
VI REFERENCES 18
VII APPENDICES 22
APPENDIX A. THE TEXACO SYNTHESIS GAS GENERATION PROCESS 22
A-l. Current Use of the Texaco Process 22
v
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TABLE OF CONTENTS (Continued)
A-2. Operational Considerations; Variety of Products 22
A-3. Coal as Feedstock 28
APPENDIX B. SYSTEM COST ESTIMATION 28
Design Criteria 32
Capital Costs for Various Types of Electric
Power Plants 32
Estimated Fuel Costs 32
Estimated Savings Using Texaco System 32
Cost of Producing Electricity 32
vi
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LIST OF EXHIBITS
Page
Exhibit Number
1 Location of Participating Louisiana
Municipalities 2
2 Air Gasification With Combined Cycle
(Simplified Diagram) 7
3 Compositions and Heating Values of Gases
Produced 11
4 Soot Recovery and Recycle System 13
5 Synthesis Gas Generation Process Plant
Owners and Locations 23
6 Recent Texaco Synthesis Gas Generation
Plants: Location, Feedstock, and Final
Product 26
7 Texaco Synthesis Gas Generation Plans Using
Heavy Oils as Feedstock 27
8 Chemical Reactions in the Partial Oxidation
of a Hydrocarbon 29
9 Compositions of Solid Feedstocks 30
10 Compositions of Gases Produced from Solid
Feedstocks 31
11 Design Criteria: Gasification, Purification,
and Combined Cycle Power Plant 33
12 Estimated Fuel Costs for Selected Types of
Electric Power Plants 34
13 Estimated Savings Using Texaco System
@ 12.99 M/KWH 35
14 Cost of Producing Electricity 36
15 Clean Fuel Gas Manufacture-Economics 38
vii
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SECTION I
INTRODUCTION
A group of Louisiana cities that own electric utility systems are
forming a joint authority, under recently enacted State legislation, to
build a 115-mw gasifier/combined-cycle generating plant and to arrange
for the transmission of the electrical energy to the participating
municipalities. The participants in this joint undertaking are the
cities of Morgan City, Natchitoches, Opelousas, Thibodaux, and Frank-
lin. 4,13* Present plans contemplate the distribution of electrical
energy from the generation site to the participating municipalities via
existing commercial transmission facilities. Airline distance between
the two most widely-separated towns, Thibodaux and Natchitoches, is
approximately 190 miles (see Exhibit 1). Current estimates place to-
day's cost of the plant at about $50 million or $435 per kw of capa-
city, although this figure is sensitive to inflation factors.17
Because of apparent similarities between the proposed Louisiana plant
and another low-emission gasification/cleanup/combustion system for use
in electric power generation that has been the subject of EPA-sponsored
research (the chemically active fluid bed (CAFB) process^)t the Office
of Energy, Minerals, and Industry of the U.S. Environmental Protection
Agency asked the MITRE Corporation to prepare a description of the
proposed Louisiana electric power generation system, with emphasis on
the gasifier and gas clean-up portions of the overall system.
The following sections of this report present, first, an overview of the
total system for producing electric power from carbonaceous or hydro-
carbon fuels, and second, more detailed information on the operation and
performance of certain of the major components in the gas production and
cleanup portions of the system.
-'Superscripts denote information sources identified in the References
(Section VI).
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NATCHITOCHES
OPELOUSAS
FRANKLIN
THIBODAUX
MORGAN CITY
0
i-
25 50
100
SCALE OF MILES
Exhibit 1. Location of participating Louisiana municipalities
2
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SECTION II
SUMMARY
The gasification/combined-cycle system proposed to generate 115 mw
electric power employs a gasifier that is widely used in industry the
Texaco Synthesis Gas Generation System. The operational characteristics
of gasifier are well established. The gasifier accepts a variety of
low-grade petroleum residues or almost any "pumpable" hydrocarbon as
feedstock, and forms a low-Btu fuel gas (100-150 Btu/ sfc) by partial
oxidation. Sensible heat from the fuel is recovered in the form of
high-pressure steam that is used to drive a steam turbine in the com-
bined-cycle portion of the system. The cooled fuel gas is then cleansed
of soot and particulate matter (by water wash) and sulfur compounds (by
an absorption system) before being burned to drive the gas turbine of
the combined cycle. Overall thermal efficiency of the system is esti-
mated at about 38 to 40 percent.
Overall costs of the proposed system are estimated at about $50 mil-
lion. For a hypothetical system of this size, about 37 percent is for
the gasification and gas cleanup portions, 46 percent for the electric
generations section, and 17 percent for offsite facilities (fuel storage,
cooling towers, etc.).
The interface between the gasification/cleanup sections and the turbine
combustor has been successfully demonstrated on a pilot-scale system.
Tests indicate that NOX emissions are lower than those produced by
natural gas firing and CO emissions are about the same. The ability of
a gasification/combined-cycle system to respond to fluctuations in
electric power demand has been investigated by means of computer models
which indicate that load changes can be successfully followed.
The joint commission of five municipalities in Louisiana is currently
proceeding with plans to implement the 115 mw power generation facility.
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SECTION III
CONCLUSIONS
The proposed gasification/combined-cycle system is an
innovative approach for meeting the specified electric
power generation requirements. The technical and econo-
mic feasibility of the system has been investigated in
detail by a series of studies that take into account
environmental impacts of the system's operation.
The proposed system provides potential for utilizing
a variety of low-grade petroleum fractions and possibly
coals as fuel feedstocks for meeting the specified
power demands.
The proposed system bears similarity to the chemically
active fluid bed (CAFB) system being investigated by
EPA in that it exhibits relatively high overall effi-
ciency (compared with conventional systems), accepts
a range of liquid hydrogen feedstocks, and is modular
in size. However the proposed system differs from the
CAFB in that it employs pressurized partial oxidation
instead of atmospheric pressure and requires post-gasi-
fication removal of sulfur compounds instead of direct
removal by solid sorbent during the combustion step.
The proposed Lousiana facility has the potential for
producing valuable data on operational parameters and
pollutant emissions during start-up, load-change, and
steady-state conditions.
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SECTION IV
RECOMMENDATIONS
MITRE recommends that EPA consider, in its planning,
communication with organizations participating in the
development of the Louisiana facility, with a view
toward acquiring data from the testing and operation
of the facility and its component processes and equip-
ment.
MITRE recommends that this action be taken immediately
so that any special instrumentation needed for measure-
ments of interest to EPA might be installed during con-
struction of the facility rather than retrofitted.
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SECTION V
OVERVIEW OF THE GASIFICATION/COMBINED-CYCLE SYSTEM
SYSTEM DESCRIPTION
The overall system converts heavy hydrocarbon fuels such as residual
petroleum products, possibly with high sulfur content, into a clean,
low-Btu gas that is used to fire a gas turbine in a combined-cycle elec-
trical generation system. Heat from the gasification step is recovered
in the form of steam, which is combined with steam generated from the
gas turbine exhaust to drive the steam turbine of the combined-cycle
system.
The more important interrelations within the overall system are shown by
the simplified flow diagram in Exhibit 2. (This diagram, adapted from
Figure 9 of Reference 7 and Figure 1 of Reference 9, is essentially
similar to a block diagram for the proposed Louisiana facility as pre-
sented in an early report on this facility.-')
Hydrocarbon fuel is pumped into a gasifier vessel (B)* where it is
partially oxidized under elevated pressures (typically 10 to 40 atmo-
spheres) and temperatures (1800 to 3000 F) to yield a low-Btu fuel gas
mixture. The oxidant is atmospheric oxygen in the compressed air that
is fed to the gasifier at a controlled rate to maintain an oxygen-to-
fuel ratio of about half the value required for complete combustion.
Under these conditions, the hydrocarbon is converted principally to
carbon monoxide and hydrogen with some formation of carbon dioxide,
steam, and carbon (soot). About 98 percent of the carbon content of the
fuel is gasified in a single pass.
In the highly reducing environment of the gasifier, sulfur in the fuel
reacts to form hydrogen sulfide (H2S), carbonyl sulfide (COS), and
carbon disulfide (82) Nitrogen in the fuel reacts to form ammonia
(NH3) and molecular nitrogen (N2). Conditions in the gasifier do not
promote the formation of oxides of sulfur (SOX) or of nitrogen (NOX).
The fuel gas mixture that emerges from the gasifier contains soot and
ash and may contain sulfur compounds; these materials must be removed
before the mixture is suitable as a gas turbine fuel. Metals in the
fuel feedstock are present in the ash as sulfides, suboxides, and
possibly other forms. The ash is partially sequestered in the soot
^Letters in parentheses refer to items of equipment in Exhibit 2.
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g
H
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within the gas stream. After the fuel gas stream emerges from the waste
heat boiler (C), it is water-scrubbed in a soot recovery system (D),
which operates effectively on the high pressure gas to remove soot, ash,
and any ammonia that was formed in the gasifier. The soot/water stream
is then contacted with naphtha whereupon the soot is transferred to the
naphtha phase. The (immiscible) naphtha phase and water phase are sepa-
rated by decanting and the water is recycled for use in the gas scrubber.
Soot is separated from the naphtha by flashing. Ash is removed from the
soot by a process proprietary to Texaco Development Corporation, and is
accumulated for disposal or for possible recovery of metallic values.
(A flow chart of the soot recovery system is shown in Exhibit 4, page
13.)
The gas stream leaving the soot recovery system is cooled but still
under high pressure. It is sent to a cleanup system for removal of sul-
fur compounds. Several candidate cleanup systems have been evaluated,
but the final selection for use in the Louisiana power plant has not
been made. Sulfur compounds (principally H2S) separated from the gas
stream are sent to a Glaus unit where the sulfur is converted to the
elemental form. The cleaned fuel gas stream is now ready for use in the
combustor (G) and the gas turbine. It is emphasized that the fuel gas
in this stream must be virtually free of particulate matter and H2S
because of possible damage to the gas turbine by these materials.
After adjustment of the temperature and pressure of the fuel gas stream,
the gas enters a combustor unit (G) where it is burned with compressed
air as the oxidant. The hot exhaust gases drive a gas turbine (H),
which in turn drives an electric generator (I) and an air compressor
(J), which supplies compressed air to the turbine. A portion of the
compressed air is bled off and used as input to the gasifier. Because
of the higher pressures in the gasifier, boost compression of the side
stream is necessary (P).
Sensible heat is recovered from the turbine exhaust gases by a waste
heat boiler (K), which generates high pressure steam that is used, in
combination with steam produced by the gasifier/waste heat boiler (C),
to drive a steam turbine (L) which, in turn, drives a second electrical
generator (N). Partially cooled exhaust gases emerging from the low-
temperature side of the waste heat boiler (K) are used to pre-heat feed
water to the boiler. The cooled exhaust gases are then vented to the
atmosphere. Exhaust steam from turbine (L) is condensed, used for
cooling in the soot extraction system (D), ars recycled for boiler feed.
TYPES OF FUELS
The gasification portion of the proposed Louisiana system employs the
Texaco Synthesis Gas Generation Process (TSGGP) which will accept a
variety of hydrocarbon feedstocks. Most liquid hydrocarbons that can be
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pumped (including low-cost refinery residues that do not meet commercial
fuel oil specifications) can be used as feedstock, since sulfur and
metals content are not critical. There is a recommended limit on the
salt level in the feedstock (not to exceed 10 pounds of salt per 1000
barrels) which may require desalting of some feedstocks prior to gasi-
fication. This is because sodium in the salt is generally deleterious
to the refractory lining of the gasifier. The use of a great range of
petroleum derived feedstocks has been amply demonstrated in TSGGP units
around the world (See Appendix A).
During the first two years' operation of the proposed Louisiana facility,
it is expected that the operating agency will have a base commitment for
vacuum residuum fuels, with potential for later utilization of other
fuel types.^ The indicated flexibility of the TSGGP process in utilizing
different fuels for the clean production of electric power can be of
great advantage to the utility organization facing a choice of fuel
sources. In addition, the potential for using coal in the form of oil
or water slurry appears promising for this gasification system. A
Texaco patent describes a gasifier designed to operate on a water slurry
of petroleum coke.° A commercial gasifier that operated on coal was
installed for use in ammonia synthesis at an Olin Mathieson plant in
West Virginia over 17 years ago.8 if this potential for utilizing coals
as fuel is realized in commercial practice, it could offer great advan-
tage to the operators of the proposed Louisiana facility by permitting
the utilization of low cost lignite from deposits in the northern part
of the State.
ENERGY AND EFFICIENCY RELATIONSHIPS
The overall plant efficiency for converting chemical energy of the fuel
into electrical energy is estimated at 38 percent. This estimate is
based on a detailed design analysis of a 294-megawatt plant employing
today's off-the-shelf machinery and components. Substantial improve-
ments in overall thermal efficiency are expected as allowable inlet
temperatures for gas turbines can be increased.
The key to the efficiency and the economics of the gasification/combined-
cycle system is the efficient utilization of sensible heat. Typically,
the gas produced by the gasifier contains about 70 percent of the gross
heating value of the fuel as chemical energy, principally in the form of
carbon monoxide and hydrogen, with a heating value of about 100 to 150
Btu per cubic foot (cold gas basis). Most of the remaining 30 percent
is in the form of sensible heat of the product gas stream. Most of the
sensible heat is recovered in the form of steam at about 1000 to 1500
psi by means of an appropriately designed heat exchanger (waste heat
boiler). Burner efficiency in the turbine combustor is typically
greater than 99 percent.
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In the analysis of the 294 megawatt system alluded to above, just under
half of the electrical energy output (145 mw) is produced by two gas
turbines and just over half (149 mw) by a steam turbine.7
The difference in overall thermal efficiency of a system employing
gasification instead of direct burning of fuel is a decrease of about
1.5 percent, which reflects minor losses of mass in the gas purification
steps and some loss of low quality heat. This penalty is more than off-
set by the advantages offered by gasification, including flexibility in
fuel supply, increased reliability, and decreased maintenance of tur-
bines resulting from the use of ultraclean gas in the .gas turbine com-
bustor.7
CHARACTERISTICS OF FUEL GAS PRODUCED
Composition and heating values of typical fuel gases produced by the
Texaco Synthesis Gas Generation Process and used as combustor fuel in a
combustor test program conducted at Texaco's Montebello Research Labora-
tory are given in Exhibit 3.
The Texaco Synthesis Gas Generation Process has the capability of
producing a range of gas compositions to meet different product require-
ments. (See Appendix A.) For the purpose of generating a clean fuel
for a nearby combined cycle operation, there is no advantage to pro-
ducing a medium-to-high energy content fuel rich in hydrogen or methane.
In fact, there may be some disadvantage from the standpoint of energy
penalty and increased NOX formation in the turbine combustor. Composi-
tions of gases produced under different conditions with different fuels
are given in Appendix A.
POLLUTANTS IN WASTE DISCHARGES
The proposed gasification/combined-cycle system, while not totally
pollution free, is expected to operate well within all applicable
environmental standards. The system itself imposes strict requirements
that the fuel gas be essentially free of particulates and acidic sulfur
compounds before it is burned as turbine fuel. (The concentration of
particles of various sizes expected to remain in the gas stream after
cleanup was not determined in the present study.)
Nitrogen and Nitrogen Compounds
The strong reducing environment in the gasifier converts virtually all
fixed nitrogen in the fuel to ammonia or free nitrogen. Measurements on
the raw fuel gas from the gasifier reveal a nitric oxide (NO) content of
only a few parts per billion, and other oxides of nitrogen in even
lower concentrations. Ammonia produced in the gasifier is removed by
the water wash in the soot extraction process. The potential exists for
the formation of nitrogen oxides during combustion of the fuel in the
10
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turbine combustor unit. However, because of the low-heating value of
the fuel gas and the relatively low combustion temperatures, the rate of
NOX formation is significantly lower than with conventional fuels.
Tests of NOX emissions at Texaco's semi-works scale gasifier coupled
with a combustor for a gas turbine indicated the concentration of NOX in
end-of-system emissions from the combustion of low heating value gas
(110-150 Btu/cu. ft.) is about one-third of that produced by burning No. 2
fuel oil and one-half of that from natural gas.7
Soot and Unburned Fuel
Particulate and amorphous carbon and other unburned fuel is removed from
the gas stream by a water wash. It is separated from the water by
additional processing steps (see Exhibit 4), and mixed with the feed-
stock supply to the gasifier. The solid carbon is thus "recycled to
extinction".
Metals and Metallic Compounds
Metals in the feedstock are converted to sulfides, lower oxides, or the
elemental state by the strong reducing conditions of the gasifier.
These emerge in the gasifier output as ash, or under some conditions may
form a slag in the gasifier. Under the present system concept and
design, metals are removed with other ash components in the gas stream
during the water-wash step of the soot removal system, and are separated
from the soot by a proprietary process before the soot is recycled to
the gasified feed.
Sulfur and Sulfur Compounds
Sulfur in the feedstock emerges from the gasifier in the form of t^S,
COS, and possibly CS2- The greater part of these materials remain in
the fuel gas stream as it goes through the waste heat boiler and soot
removal system, and are removed thereafter by acid gas clean-up pro-
cedures. Several such procedures have been evaluated for this purpose,
including those based on a physical absorption approach (such as the
Rectisol or the Selexol process) and those based on chemical absorption
(such as the Benfield or the Catacarb process). It is recognized that
for the combined cycle operation, there would be some advantage to a
process that operates at elevated temperatures so that the fuel gas
would not have to be cooled to a low temperature before clean-up; also,
to a process that removes the acidic sulfur compounds while leaving
carbon dioxide in the gas stream, since expansion work could be realized
from the carbon dioxide as it goes through the gas turbine.
12
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When the acid gases are removed from the fuel gas, the hydrogen sulfide
is sent to a Glaus unit for recovery of the sulfide values as elemental
sulfur with a conversion efficiency of about 99 percent. Most of the
remaining sulfur is in the exhaust gas from the Glaus unit in the form
of S02, and can be removed by a conventional scrubber. The volume of
exhaust gas from the Glaus unit is miniscule in comparison with the
exhaust from the gas turbine, hence it can be cleaned with much less
expense and greater efficiency than could the entire throughput of the
turbine.
INTEGRATION OF THE GASIFICATION AND COMBINED CYCLE SUBSYSTEMS
In addition to the use of clean fuel from the gasifier to fire the
turbine combustor, there are .several points at which the gasification
portion and the combined-cycle portion of the overall system depicted in
Exhibit 2 are interrelated to enhance overall system efficiency. In
particular:
Part of the air from the turbine compressor is bled off,
boosted in pressure, and fed to the gasifer. Since most
of the mass of air removed for use in the gasifier is re-
turned to the turbine with the fuel gas, there is little
if any change in net turbine mass flow using fuel gas
from air gasification relative to the mass flow through
the turbines if conventionally fueled. Hence existing
turbines can use this fuel gas without aerodynamic modi-
fications to the blading. Some changes are required in
the flow control system.
Condensate from the steam turbine is used for cooling
in the gas purification step and is recycled to the
feedwater in the combined-cycle.
DEVELOPMENTAL STATUS OF THE GASIFIER/COMBINED CYCLE SYSTEM
An experimental/developmental program was conducted in 1972-73 as a
cooperative effort by Texaco, Inc., and two component organizations of
United Aircraft Corporation (Turbo Power and Marine Systems, Inc., and
Pratt and Whitney Aircraft) to assess the feasibility of using fuel gas
from the TSGG gasifier in industrial gas turbines and to evaluate dif-
ferent combustion chambers and fuel injection arrangements over a range
of operating parameters. Gas with heating value of 100 to 150 Btu per
standard cubic foot was burned in one can (i.e., a 1/8 segment) of a
PWA FT4 combustor.
Test results demonstrated that low Btu gas can be efficiently used in a
gas turbine, that NOX emissions will be lower than those produced by
firing with natural gas, and CO emissions will be about the same as with
14
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natural gas firing. The tests also indicate which modifications are
required for the fuel introduction system, combustion chambers, and air
bleed rates relative to those in a natural gas fired system.9
In addition to the large scale experimentation and demonstration by
Texaco and others, a mathematical model of major portions of this type
of system (the gasifier, gas cleanup, gas turbine/generator and booster
compressor) has been developed by C.F. Braun & Co. for dynamic simula-
tion studies. Since gasification processes normally operate at a steady
state over long periods and gas turbine/generators can experience rapid
fluctuations in load and require varying fuel demands, the question
arises of the ability of the gasification section of the system to
respond to changing fuel flow requirements when there is no inter-
mediate fuel storage. The C.F. Braun model facilitates investigation of
the dynamic response of various system components under conditions of
changing load. The simulation study indicates that "... the combined
plant is a stable system and that the fuels plant can follow load fluc-
tuations in the power generating system without upsets. It shows fur-
ther than the system can be automated by conventional control equipment
to operate with a minimum of manual supervision. "-1-
In the latter half of 1974, Beard Engineering, Inc., of Baton Rouge
published reports of two studies that indicate the feasibility of using
a gasifier/combined-cycle system to power electrical generating facili-
ties in Louisiana (References 2 and 3). On the basis of these and sub-
sequent studies, plans have been developed for building a gasification/
combined-cycle electric power plant to serve five municipalities in
Louisiana. Enabling legislation has been enacted by the State Legisla-
ture which permits local governments to enter jointly into such an
enterprise. The five municipalities identified in Section I estab-
lished, in October 1975, a joint commission names "Louisiana Municipal
Power Commission" (LAMPCO). This commission has retained the services
of bond counsel and investment banking firms, and is proceeding with
plans to implement the proposed 115 raw central power facility on which
a study is now being completed.^
System Cost
According to a 1973 cost estimation procedure prepared by Texaco, Inc.,
the cost of a 294 mw plant is estimated at $70.5 million, or about $240
per kw capacity (Appendix B). At this rate, the 115 mw Louisiana
facility would cost about $28 million. Capital costs are, of course,
highly sensitive to inflation. Current estimates place the cost at
about $50 million, although it is recognized that additional inflation-
ary effects can occur before bids are received.-'-'
15
-------
The gasification and gas cleanup portions of a hypothetical 150 mw
system are estimated to account for 37 percent of the overall invest-
ment, the electric generation section about 46 percent, and the offsite
facilities (fuel storage, cooling water distribution, cooling towers,
etc.) for about 17 percent of the overall system capital costs.20
In the proposed Louisiana facility, the sulfur removal portion of the
system is estimated to account for about five to six percent of the
overall system costs.4
The present study revealed no up-to-date estimates for the cost of
electrical energy from a gasification/combined-cycle system. Texaco's
cost estimation procedure (reproduced in Appendix B) is based on 1973
costs of equipment, labor, and fuel; hence its estimated cost of elec-
tricity produced (given in Appendix B) is not applicable to current
conditions. The procedure could be used with updated inputs to yield
new estimates of product electricity costs that more nearly reflect
current conditions. The procedure can also be used for estimating
equipment, labor, fuel, etc. It is noted that the value assigned to the
feedstock accounts for a large part of the cost of producing clean fuel
gas. For example, residual oil at a cost of $8 per barrel represents
about 80 percent of the cost of clean fuel gas produced using air as the
oxidant.? Relations between the cost of producing fuel gas and the cost
of residuum feedstock are given in Exhibit 15 of Appendix B.
COMPARISON WITH CAFB PROCESS
The TSGGP process has certain points of similarity with the CAFB process
of ESSO Ltd., being investigated by EPA. Both can be used with a variety
of low grade petroleum fractions to generate fuel gas for electric power
generation while releasing relatively low quantities of atmospheric
pollutants. Both exhibit relatively high overall thermal efficiency,
and both are essentially modular in size, in that there is an effective
upper limit to the capacity of existing units. Multiple units can be
combined to obtain large plant capacity for steam or electrical energy
generation without loss in efficiency.
There are, however, several dissimilarities between the TSGGP and the
CAFB approaches. Principal among these are the pressurized partial
combustion in the gasification/combined-cycle system employing the
TSGGP, with its requirement for scrubbing of H2S and its production of
ultra-clean fuel gas to fire a gas turbine. The CAFB process, on the
other hand, employs atmospheric partial combustion with direct removal
of sulfur components by fluidized solid sorbent. The CAFB approach has
potential for retrofit to existing steam-to-electric generators. When
used in a retrofit mode, the CAFB could not be expected to attain as
high a thermal efficiency as the gasifier/combined-cycle system.
16
-------
POTENTIAL OPPORTUNITIES FOR ENVIRONMENTAL R&D; RECOMMENDATIONS
The proposed Louisiana facility has the potential for producing valuable
data on the operational parameters and pollutant emissions during steady-
state operation as well as startup and load change conditions. Such
information would be useful not only to indicate the efficiency and
cleanliness of operation of this overall facility and its component
processes, but to permit comparison of this system with others that
serve similar markets, such as the CAFB process.
The design engineer has indicated that operational data would routinely
be recorded during the operation of the facility and that test data
would be developed. He expressed the opinion that such data would be
available to EPA and other organizations having legitimate interests in
the facility's operations.^ A member of the management of the Texaco
Development Corporation also has indicated that, under proper circum-
stances, the Corporation might be receptive to EPA's request that EPA
representatives be allowed to visit the gasification facility at Texaco's
Montebello Research Laboratory.22
In view of EPA's interest in demonstrating new methods for utilizing
fossil fuels in an environmentally acceptable manner, its involvement in
R&D of processes for accomplishing this aim, and the above-cited expres-
sions of cooperation by organizations involved in the proposed full-
scale Louisiana plant, MITRE strongly recommends that EPA consider in
its planning the initiation of communications with organizations parti-
cipating in the development of the Louisiana facility in an effort to
acquire data from the testing and operation of this facility and its
component processes and equipment. MITRE further recommends that this
action be undertaken immediately in order that any special instrumenta-
tion needed for measurements of interest to EPA, but not routinely taken
by the owners/operators of the facility, might be installed during the
construction of the plant rather than retrofitted after construction is
completed.
17
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SECTION VI
REFERENCES
1. Balekjiam, Garen, "Compatibility of Partial Oxidation Plant and
Combined Cycle Power Plant Dynamics," C.F. Braun and Co., Prepared
for presentation at EPRI Conference, Monterey, California, April
8-10, 1974.
2. Beard Engineering, Inc., "Engineering and Economic Feasibility
Study of a Texaco Synthesis-Gas Combined-Cycle Generating Plant
for a Typical Louisiana Municipal Electric Utility System," Pre-
pared for the State of Louisiana Department of Conservation by
Beard Engineering, Inc., Baton Rouge, August 1974.
3. Beard Engineering, Inc., "Engineering and Economic Feasibility
Study of a Proposed Central Synthesis-Gas Power Plant for Munici-
pal Electric Generation for the Cities of Morgan City, Louisiana,
Natchioches, Louisiana, Opelousas, Louisiana, and Thibodaux,
Louisiana," Prepared by Beard Engineering, Inc., Baton Rouge,
December 1974.
4. Beard, Harold, Beard Engineering, Inc., Baton Rouge, Louisiana,
Personal communications, October 6 and December 8, 1975.
5. Child, E.T., "Texaco: Heavy Oil Gasification," Texaco Develop-
ment Corporation, New York City, Prepared for presentation at
the University of Pittsburgh Symposium on Coal Gasification
and Liquefaction, August 6-8, 1974, Pittsburgh, Pennsylvania.
6. Child, E.T., Technical Associate, Texaco Development Corporation,
New York, New York, Personal communication, September 17, 1975.
7. Child, E.T., and R. McGann, "Gasification of Residual Oils for
Use in Combined Cycle Power Generation," Texaco Development
Corporation, New York, N.Y., for presentation at the Japan
Petroleum Institute Refining Committee Meeting, Tokyo, May 8-9,
1975.
8. Conn, A.L., "Low B.t.u. Gas for Power Plants," Chemical Engineering
Progress, December 1973.
18
-------
REFERENCES (Continued)
9. Crouch, W.B., W.G., Schlinger, R.D. Klapatch, and G.E. Vitti,
"Recent Experimental Results on Gasification and Combustion of
Low BTU gas for Gas Turbines," Contributed by Gas Turbine Division
of ASME for presentation at Gas Turbine Conference and Product
Show, Zurich, Switerland, March 30-April 4, 1974, ASME Publica-
tion No. 74-GT-ll, American Society of Mechanical Engineers, New
York, N.Y., (A somewhat modified version of this paper was pub-
lished in Combustion, April 1974).
10. Crouch, W.B., W.G. Schlinger, and C.P. Marion, "Partial Combustion
of High-Sulfur Fuels for Electric-Power Generation," Texaco, Inc.,
Montebello, California (Undated).
11. Eastman, deBois, "Synthesis Gas by Partial Oxidation," Industrial
and Engineering Chemistry, July 1956.
12. Eastman, de Bois, "The Production of Synthesis Gas by Partial
Oxidation," Section IV, Paper 13, Proceedings of 1959 World
Petroleum Congress.
13. "Five La. Towns Organize to Build 115-MW Gasifier/Combined-Cycle
Plant," Electrical Week, McGraw-Hill, August 11, 1975.
14. "Gas Processing Handbook," Summary of processes for sulfur removal,
tail gas cleanup, SNG production, and other processes, Hydrocarbon
Processing, April 1975.
15. Keairns, D.L., R.A. Newby, E.J. Vidt, E.P. O'Neill, C.H. Patterson,
C.C. Sun, C.D. Buscaglia, and D.H. Archer, Fluidized Bed Combustion
Evaluation, Volume ISummary, Prepared for Westinghouse Research
Laboratories for the U.S. Environmental Protection Agency, Office
of Research and Development, (EPA-650/2-75-027a), Washington, D.C.
20460, March 1975.
16. Keairns, D.L., R.A. Newby, E.J. Vidt, E.P. O'Neill, C.H. Patterson,
C.C. Sun, C.D. Buscaglia, and D.H. Archer, Fluidized Bed Combustion
Evaluation, Volume IIAppendices, Prepared for Westinghouse Re-
search Laboratories for the U.S. Environmental Protection Agency,
Office of Research and Development, EPA-650/2-75-027b, Washington,
D.C., March 1975.
19
-------
REFERENCES (Continued)
17. Kron, Harry, City Clerk, Thibodaux, Louisiana, Personal communica-
tion, October 2, 1975.
18. Marion, C.P. and W.L. Slater, "Manufacture of Tonnage Hydrogen
by Partial CombustionThe Texaco Process," Prepared for delivery
at the Sixth World Petroleum Congress, Section III, Paper 22-PD9,
pp. 373-382, of Proceedings of that Congress, 1963.
19. McCrea, D.H., and H.E. Benson, "Benfield Processes for SNG and
Fuel Gas Purification," The Benfield Corporation, Prepared for
presentation at the 165th National Meeting of the American
Chemical Society, Dallas, Texas, April 8-13, 1973.
20. Patterson, R. Dean, "Gasification Power Generation System," Turbo
Power and Marine Systems, Inc., Farmington, Connecticut, Prepared
for delivery at American Power Conference, Chicago, April 29-May 1,
1974.
21. Schlinger, W.G., and W.L. Slater, "Application of the Texaco Syn-
thesis Gas Generation Process Using High Sulfur Residual Oils as
Feedstock," Texaco Inc., Montebello Research Laboratories, Monte-
bello, California (Undated).
22. Sellers, F.B., Manager, Process Division, Texaco Development Cor-
poration, New York, N.Y., Personal communications, September 17
and October 3, 1975.
23. Slater, W.L., A.M. Robin, and W.G. Schlinger, "Partial Combustion
of High Sulfur Residual Fuels for Direct Production of Methane-
Rich Fuel Gas," Texaco, Inc., Prepared for publication in the
Japanese Journal of the Petroleum Institute, Paper No. 1733,
(Undated).
24. "SNG Process Description: Benfield Corporation C02 Removal Process
for SNG Plants," Pipeline and Gas Journal, October 1972.
25. Texaco Development Corporation, "Coal Gasification Process,"
(Brochure) Texaco Development Corporation, New York, N.Y.,
August 27, 1974.
26. Texaco Development Corporation, "Low-Btu Gas/Combined-Cycle Power
GenerationPower Production from High-Sulfur High-Ash Fuels With-
out Pollution," (Informal Brochure), New York, N.Y., January 1974.
20
-------
REFERENCES (Concluded)
27. Texaco Development Corporation, "High-Pressure Hydrogen by Partial
Combustion of High Sulfur Residual Oils," Texaco Development Cor-
poration, New York, N.Y. (Undated).
21
-------
SECTION VII
APPENDICES
APPENDIX A. THE TEXACO SYNTHESIS GAS GENERATION PROCESS
A-l. Current Uses of the Texaco Process
The Texaco Synthesis Gas Generation Process (TSGGP) is a widely used,
well established process for converting hydrocarbon feedstocks to a
variety of gaseous products, principally high purity hydrogen for ammo-
nia production and synthesis gas (mixtures of carbon monoxide and hydro-
gen) for use in the manufacture of chemicals. Currently, the TSGGP is
used in over 60 commercial plants around the world. Exhibit 5 is a
partial listing of companies that use the process, their locations, and
the feedstock used. Single commercially-proven TSGGP units can produce
up to 110 million SCFD of hydrogen plus carbon monoxide. Exhibit 6
shows the final product as well as feedstock of 16 recent installations.
Exhibit 7 summarizes capacity, feedstock, and product information for
plants in which heavy oils are used as feedstock. Such oils are planned
to be used as feedstock in the initial operation of the proposed Louis-
iana plant.
A-2 Operational Considerations; Variety of Products
In the TSGGP process, the partial oxidation reaction takes place within
a refractory-lined pressure vessel. It is basically a non-catalytic
flame-type reaction involving the incomplete oxidation of a hydrocarbon
feedstock with air, oxygen-enriched air, or oxygen introduced in less-
than-stoichiometric quantities. An excessive ratio of oxidant to hydro-
carbon will cause an undesired degree of complete oxidation, producing
carbon dioxide and water. To keep the production of soot at acceptably
low levels when oxygen or enriched air is used as the oxidant, it is
necessary to operate at oxygen rates that yield reaction temperatures
higher than can be handled by commercially available refractories.
Hence when these oxidants are used, steam is added to the reaction as a
temperature moderator. The steam may also serve as a source of hydrogen
when a high-hydrogen-content product is desired. When air is the oxi-
dant, the nitrogen content serves as the temperature moderator.
22
-------
Exhibit 5. SYNTHESIS GAS GENERATION PROCESS PLANT OWNERS AND LOCATIONS*
OWNER
ANIC S.p.A.
ANIC S.p.A.
Asahi Chemical Industry Co.,Ltd.
PLANT LOCATION
Gela, Sicily
Bavenna, Italy
Nobeoka, Japan
RAW MATERIAL
Natural Gas
Natural Gas
Crude Oil
Badische Anilin & Soda Fabrlk A.G.
BASF (Plant II)
Borden International (Alba, S.A.)
Brockville Chemicals, Ltd.
Ludwigshafen/Rhein,
Germany
Ludwi gshafen/Rhein,
Germany
Cubatao, Brazil
Maitland,-Ontario
Heavy Fuel Oil
Heavy Fuel Oil
Heavy Fuel Oil
Natural Gas
Compania Insular del Nitrogeno,S.A.
Courrie re s-Kuhlmann
C.S.R. Chemicals Ltd.
Las Palmas,
Canary Islands
Harnes, France
Sydney, Australia
Heavy Fuel Oil,
Naphtha
By-product Gas
Heavy Fuel Oil
E. I. duPont de Nemours & Co.,Inc.
Huron, Ohio
Natural Gas
The Fertilizers & Chemicals
Travancore Ltd. (Stage II)
The Fertilizers & Chemicals
Travancore Ltd. (Stage III)
Alwaye, Kerala
State, South India
Alwaye, Kerala
State, South India
Naphtha
Naphtha, Heavy
Fuel Oil
W. R. Grace & Company
.(Nitrogen Products Div, )
VToodstock, Tennessee
Natural Gas
Hemijska Industrija Pancevo
(Invest-Import representing
Fabrika Azotnih Djubriva - HIP)
Pancevo, Yugoslavia
Natural Gas or
Heavy Fuel Oil
*As of 4/1/70
SOURCE: Reference 22
Page 1 of 3
23
-------
Exhibit 5. (Continued)
Imperial Chemical Industries, Ltd.
Imperial Oil Co. (Esso1!
Kaohsiung Ammonium Sulfate Corp.,
Ltd.
PLANT LOCATION
Billingham, England
Dartmouth, N.S.
Kaohsiung, Taiwan
Government of the Republic of Korea Chung-Ju, Korea
Establisseroents Kuhlmann
La Madeleine Les
Lille, France
RAW MATERIAL
Heavy Fuel Oil,
Naphtha
LPG
Heavy Fuel Oil
Navy Special
Fuel Oil
Naphtha
Nippon Steel Corporation
Nitratos de Castilla, S.A.
Nitto Chemical Industry Co., Ltd.
Nitto Chemical Industr" Co., Ltd.
NV Nederlandse Staatsmi.lnen
Hirohata, Japan
Valladolid, Spain
Hachinohe, Aomori,
Japan
Yokohama, Japan
Geleen, Netherlands
Heavy Fuel Oil
Heavy Fuel Oil,
Naphtha
Crude Oil
Crude Oil
Natural Gas
Petroleo Brasileiro, S.A.
Phosphoric Fertilizers Industry
Sociedade Portuguesa de
Petroquiraica, S.A.R.L.
Manifattura Ceramica Pozzi,S.p.A.
Cubatao, Brazil
Kaval^a, Greece
Lisbon, Portugal
Ferrandina, Italy
Refinery Gas
Crude Oil
Naphtha
Acetylene Tail
Gas, Natural Gas
Resins Inc.
Rohm and Haas Co.T.nany
Cayagande, Oro, P.I.
De<=>r Park, Texas
Heavy Fuel Oil
Natural Gas,
Acetylene Tail
Gas
Page 2 of 3
24
-------
Exhibit 5. (Continued)
Seitetsu Kagaku Company, Ltd.
(Formerly Befu Chemical Co., Ltd.)
Showa Denko K.K. - Plant 1
Showa Denko K.K. - Plant 2
Aktiebolaget Svenska
Salpeterverken - Plant I
Aktiebolaget Svt-.iska
Salpeterverker - Plant II
Standard Oil Co. of California
PLANT LOCATION
Hyogo-Pref., Japan
Kawasakl-shi,
Kanagawa-ken, Japan
Kawasaki-shi,
Kanaga,wa-ken, Japan
Kvarntorp, Sweden
Kvarntorp, Sweden
El Segundo, Calif.
RAW MATERIAL
Crude Oil
Refinery Gas,
Crude Oil
Crude Oil,
Refinery Gas
Heavy Fuel Oil,
Shale Oil
Heavy Fuel Oil
Vacuum Resid
Taiwan Fertilizer Corporation,
Factory No. 7
Texaco Inc.
Tokuyama Soda Company, Ltd.
Toyo Soda Manufacturing Co.,Ltd.
Toyo Koatsu Industries, Inc.
Ube Industries, Ltd. - Plant 1
Ube Industries, Ltd. - Plant 2
Hualien, Taiwan
Los Angeles, Calif.
Yamaguchi-Pref.
Ja,pan
Yamaguchi-ken,
Japan
Omuta, Japan
Ube, Yamaguchi-
Pref., Japan
Ube, Yamagu chi-
Pref., Japan
Heavy Fuel Oil
Heavy Fuel Oil
or Vacuum
Residuum
Crude Oil
Crude Oil
Crude Oil
Crude Oil
Crude Oil
Page 3 of 3
25
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Exhibit 7. TEXACO SYNTHESIS GAS GENERATION PLANTS
USING HEAVY OILS AS FEEDSTOCK
Country
U.S.A.
Japan
Spain
Germany
Taiwan
No. of
Plants
11
3
2
France, 1 each
Canada, Brazil,
Belgium, England,
Italy, Korea,
Sweden, Denmark,
Yugoslavia, India,
Greece, Australia
Total
Capac.
MMSCFD
H2+CO
130.3
132'. 9
46.4
51.9
10.3
183.2
Feedstocks
Hvy. Fuel Oil,
Crude Oil,
Vac. Bottoms
Hvy. Fuel Oil,
Crude Oil
Hvy. Fuel Oil
Hvy. Fuel Oil,
Crude Oil
Hvy. Fuel Oil
Hvy. Fuel Oil,
Crude Oil
Final
Products
Ammonia
Refg. Hydrogen
Ammonia,
Reducing Gas
Ammonia
Ammonia,
Oxo
Ammonia
Ammonia,
Methanol,
Oxo
Totals
35
555.0
SOURCE: Reference 22
27
-------
The gasifier equipment has proven highly reliable in long-term opera-
tion. Commercial experience reveals that refractory lining last three
to five years and burners in the gasifier have lives of several years.
Pilot units indicate no burner problems at high pressures or with highly
viscous feedstock.'
The gasifier can be operated at 10 percent of design capacity; turndown
to 50 percent or less of normal system capacity is practiced in commer-
cial units.
The partial oxidation products of a pure hydrocarbon may include carbon
monoxide, hydrogen, methane, carbon dioxide, and carbon (as soot) (see
Exhibit 8 for reactions) in addition to nitrogen and trace quantities of
nitrogen oxides if air is the oxidant. Metals, other ash components,
and sulfur compounds in the fuel may enter into side reactions to yield
byproduct materials as discussed in Section V of this report. The
composition of the product gas can be varied by controlling the oxida-
tion rate and other reaction conditions to favor a high methane content,
high hydrogen content, etc. , depending on the intended use of the pro-
duct gas, e.g., as fuel, as a source of pure hydrogen, or as a synthesis
gas for subsequent chemical processing. Considering the product gases
as a fuel, their heating value is typically in the range of 100-150
Btu/SFC if air is the oxidant, or around 300 Btu/SFC is oxygen is the
oxidant. (See Exhibit 3.)
A-3 Coal as Feedstock
The lists of current applications of the TSGGP in Exhibits 5 through 7
indicates that all of these units use gases or liquid petroleum deriva-
tives as feedstocks. Extensive experimentation on the use of coal
slurries and petroleum coke feedstocks has been conducted at Texaco"s
pilot and semi-works experimental facilities. Exhibit 9 shows ultimate
analyses and heating values of some of the solid materials that have
been gasified continuously. Exhibit 10 shows the compositions of the
gaseous products.25 Some 90 to 98 percent of the feedstock carbon is
gasified in single pass, with potential for recycling carbon extracted
from the gas stream by the soot recovery system. A commercial unit
which apparently used an earlier version of the TGSSP process, was con-
structed more than 17 years ago for use at an Ol.in Mathieson plant in
West Virginia to produce synthesis gas from coal, for use in ammonia
manufacture.&
APPENDIX B. SYSTEM COST ESTIMATION
Reproduced below are excerpts from a Texaco brochure which show cost
elements and relationships that can be used to estimate the operating
costs of a gasification/combined-cycle system and cost of products.
28
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Cost data in Exhibits 12 through 14 are from the 1973-1974 time period.
If updated costs of equipment, fuel, and labor were used, current costs
could be estimated from the relationships that follow:^"
Design Criteria - The design study was based on a fuel con-
sumption rate of 10,000 barrels per day of heavy residual
oil, using representative, rather than the most favorable,
parameters from present commercial gas turbine state of the
art as listed. (Exhibit 11.)
Capital Costs for Various Types of Electric Power Plants - The
capital costs of the various types of power plants considered
in the study are reliable in a gross sense since there are
available cost data. The costs are not precise in that such
costs vary considerably with plant location and design specifics.
For the Texaco combined-cycle plant, there are cost data for
the various plant sections or components even though the plant
being studied has not been built. None of the equipment requires
new design or development.
Estimated Fuel Costs - Fuel costs were taken from the January
15, 1974 Platt's Oilgram. While such costs have changed and
are changing rapidly, price differentials, between distillate
and low sulfur fuels on one hand and high sulfur residua on the
other, are likely to remain. This chart also gives calculated
system performance for the previously stated design criteria.
The Texaco combined-cycle plant gives very respectable perfor-
mance with higher pressure ratio, higher turbine inlet tempera-
ture and higher compression and turbine efficiencies presently
available in some units. Steam plants have been built with
thermal efficiencies of 40+ percent, but such plants are high
cost, relatively inflexible, and generally not favored by the
utility industry. The fuel costs per KWH for the various types
of plants and for the fuels and prices listed are given at the
bottom of the chart. (Exhibit 12.)
Estimated Savings Using Texaco System - The estimated savings
listed (in Exhibit 13) are for fuel charges alone, based on
the fuel costs per kwh of the previous chart (Exhibit 12).
These savings leave substantial cushion to _absorb the higher
capital investment and for differences in operating expenses
of the Texaco system as compared to the alternate systems re-
quiring low sulfur fuels.
Cost of Producing Electricity - The final chart (Exhibit 14)
estimates the cost of producing electricity by the Texaco
combined-cycle system. This estimate was made some time ago
and is based on a fuel cost of only $3.00 per barrel. However,
32
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labor and indirect operating costs are indicated in sufficient
detail so that current local unit prices could be assigned to
fuel oil, the utilities and the direct and indirect operating
costs to produce a revised cost estimate which would be appro-
priate for your particular circumstances.
Another cost relationship of interest appears in Exhibit 15. This shows
the effect of fuel prices (in this case, residual oil) on the cost of
producing clean fuel gas using air or oxygen as the oxidant.?
37
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38
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1
4.
7.
9.
12
15
16
17.
REPORT NO. 2.
TITLE AND SUBTITLE
Gasification/Combined-Cycle System for Electric
Power Generation
AUTHOR(S)
J. Bruce Truett
PERFORMING ORGANIZATION NAME AND ADDRESS
MITRE Corporation
Westgate Research Park
McLean, Virginia 22101
. SPONSORING AGENCY NAME AND ADDRESS
Office of Energy, Minerals, and Industry
U.S. Environmental Protection Agency
Washington, D.C. 20460
. SUPPLEMENTARY NOTES
3. RECIPIENT'S ACCESSION-NO.
5. REPORT DATE
.Tanuarv 1 976 ("Approval rlat-p^l
e. PERFORMING ORGANIZATION CODE
8. PERFORMING ORGANIZATION REPORT NO.
MTR-7176
10. PROGRAM ELEMENT NO.
EHE-626
11. CONTRACT/GRANT NO.
68-01-3118
13. TYPE OF REPORT AND PERIOD COVERED
Subtask Report (Final)
14. SPONSORING AGENCY CODE
. ABSTRACT
This report describes a type of gasification/combined cycle system being
considered for construction by a consortium of Louisiana cities that own electrical
utility systems. The 115 KW system is expected to employ the Texaco Synthesis Gas
Generation Process (TSGGP) to produce a fuel gas by partial oxidation of a hydro-
carbon feedstock. The gas is cleaned to remove sulfur compounds, ash, and particu-
lates, then burned as fuel for the gas turbine in a combined-cycle power system.
The commercially-proven TSGGP process accepts a large variety of hydrocarbons
as feedstocks. The initial feedstock for this application is expected to be heavy
petroleum residues, although the potential exists for utilization of coal and
lignite. Other features of the proposed system include (1) high thermal efficiency
(relative to conventional steam generators) resulting in part from efficient
recovery of thermal energy from the gasification of feedstock; and (2) extremely
low levels of pollutants (SOx, NOx) in emissions to the atmosphere.
The five participating municipalities have established a joint commission,
"Louisiana Municipal Power Commission" (LAMPCO) , which has retained the services
of bond counsel and investment banking firms, and is proceeding with plans to imple-
ment the proposed power generation facility.
KEY WORDS AND DOCUMENT ANALYSIS
a DESCRIPTORS
Electric Power Generator
Fuels
Gas Purification
Gasification
Turbogenerators
1 3
DISTRIBUTION STATEMENT
Unlimited
b. IDENTIFIERS/OPEN ENDED TERMS C. COSATI Field/Group
Partial Oxidation 13/07
Louisiana
Texaco Synthesis Gas
Generation Process
19. SECURITY CLASS (This Report) 21. NO. OF PAGES
Unclassified ^'
20. SECURITY CLASS (This page) 22. PRICE
Unclassified
EPA Form 2220-1 (9-73)
39
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