Combined goal gasifier and fuel cell system and method

A molten carbonate fuel cell is combined with a catalytic coal or coal char gasifier for providing the reactant gases comprising hydrogen, carbon monoxide and carbon dioxide used in the operation of the fuel cell. These reactant gases are stripped of sulfur compounds and particulate material and are then separated in discrete gas streams for conveyance to appropriate electrodes in the fuel cell. The gasifier is arranged to receive the reaction products generated at the anode of the fuel cell by the electricity-producing electrochemical reaction therein. These reaction products from the anode are formed primarily of high temperature steam and carbon dioxide to provide the steam, the atmosphere and the heat necessary to endothermically pyrolyze the coal or char in the presence of a catalyst. The reaction products generated at the cathode are substantially formed of carbon dioxide which is used to heat air being admixed with the carbon dioxide stream from the gasifier for providing the oxygen required for the reaction in the fuel cell and for driving an expansion device for energy recovery. A portion of this carbon dioxide from the cathode may be recycled into the fuel cell with the air-carbon dioxide mixture.

BACKGROUND OF THE INVENTION 
The present invention relates generally to the operation of a molten 
carbonate fuel cell with fuel gas derived from the gasification of coal, 
and more particularly to such an operation wherein steam and carbon 
dioxide in the reaction products generated at the anode in the fuel cell 
by the electricity-producing electrochemical reaction are utilized in a 
coal or coal char gasifier for endothermically reacting coal or char in 
the presence of a catalyst for providing the fuel gas. 
The utilization of fuel cells in relatively large electrical power 
generating applications is becoming of increasing interest to the 
electrical industry. The principal reason for this increased interest is 
primarily due to recent advancements in fuel cell technology which have 
given strong indications that electrical power generation by using fuel 
cells can be achieved at rates which may be highly competitive with many 
existing electrical power producing technologies. 
Of the various types of fuel cells being presently evaluated for possible 
commercial power production applications, molten carbonate fuel cells 
appear to be sufficiently developed to be considered a suitable candidate. 
As with all fuel cells, an electrochemical reaction is utilized in the 
molten carbonate fuel cell to convert the energy of the reaction of 
various chemicals directly into electrical energy. In a typical molten 
carbonate fuel cell there is an anode formed of a suitable material such 
as porous nickel which is separated from a cathode of a suitable material 
such as porous nickel oxide by an electrolyte formed of an alkali metal 
carbonate and mixtures thereof with a suitable material such as 
LiAlO.sub.2. When the electrolyte is heated by any suitable means to a 
temperature sufficient to become liquified or in a molten state, the 
electrochemical reaction in a molten carbonate fuel cell can proceed by 
the simultaneous delivery of hot hydrogen to the anode and hot carbon 
dioxide and oxygen to the cathode. Normally, the electrochemical reaction 
can be effectively achieved in the molten carbonate fuel cell as presently 
available at a temperature in the range of about 1100.degree. to about 
1300.degree. F. and at a pressure greater than atmospheric pressure and in 
the range of about 1.1 to about 6 atmospheres. The electrochemical 
reaction in the fuel cell is provided the reaction H.sub.2 +CO.sub.3.sup.= 
.fwdarw.H.sub.2 O+CO.sub.2 +2e.sup.- at the anode and the reaction O.sub.2 
+2CO.sub.2 +4e.sup.- .fwdarw.2CO.sub.3.sup.= at the cathode. These 
reactions produce H.sub.2 O at the anode while causing a transfer of 
CO.sub.2 from the cathode to the anode with two Faradays of charge with 
each mole of CO.sub.2. The reaction products generated during the 
electrochemical reaction in the molten carbonate fuel cell include the 
H.sub.2 O, primarily in the form of steam, and CO.sub.2 at the anode. If 
air is used as the source of the oxygen for the reaction at the cathode 
some nitrogen will be mixed with the CO.sub.2 in the stream of reactants 
at the cathode. While the efficiency of the electrochemical reaction for 
converting the reactant gases to electricity in a molten carbonate fuel 
cell is relatively high, i.e., in the order of about 80 percent, there is 
an incomplete conversion of all the reactant gases by the reaction. The 
energy in the reaction gases discharged from the fuel cell is primarily in 
the form of heat and must be recovered in order to provide the molten 
carbonate fuel cell with a level of efficiency which will make it 
commercially competitive with known electrical power producing systems. 
Any of several techniques may be utilized to recover the "waste" heat the 
reaction product gases discharged from the fuel cells. These techniques 
include the use of bottoming cycles which use boilers for the generation 
of steam for driving a steam turbine coupled to a generator or another 
suitable load. 
Reactant gases used for the electrochemical reaction in a relatively large 
scale molten carbonate fuel cell system useful for commercial power 
production purposes may be provided by one of several techniques. For 
example, the placing of suitable hydrogen and carbon dioxide producing 
plants in close proximity to one or more fuel cell systems may be one 
approach for providing the necessary reactant gases. A more recent 
approach for supplying the reactant gases believed to be worthwhile for 
consideration is the utilization of a coal or coal char gasifier for 
producing fuel gas which contains the H.sub.2 and CO.sub.2 necessary for 
the electrochemical reaction in a molten carbonate fuel cell. In order to 
use the gaseous products from a coal gasifier in the fuel cell, 
essentially all of the particulate material greater than about sub-micron 
size and the sulfur-bearing compounds must be stripped from the fuel gas. 
After removing the solid particulate material and sulfur-bearing compounds 
from the gases the CO.sub.2 and the H.sub.2 must be separated from one 
another for delivery to the appropriate fuel-cell electrodes. While there 
are several presently known techniques for removing sulfur-bearing 
compounds and particulate material from the stream of product gases from a 
gasifier and for separating hydrogen from carbon dioxide, these techniques 
must be capable providing these functions without excessively reducing the 
temperature of the gases to a level less than that required for effecting 
the electrochemical reaction in the fuel cell and maintaining the 
electrolyte in a liquid state. A discussion pertaining to the use of fuel 
gas from a gasifier in as the fuel gas for a molten carbonate fuel cell is 
set forth in a report entitled, "Analysis of Fuel Cell and Competing Power 
Plant Designs for Utility Base-Load Applications", Argonne National 
Laboratory, November 1985. This report is incorporated herein by 
reference. 
SUMMARY OF INVENTION 
The primary aim or objective or present invention is to provide a molten 
carbonate fuel cell system in which a coal or char gasifier is utilized in 
combination with the fuel cell for providing the reactant gases required 
for the electricity-producing electrochemical reaction in the fuel cell. 
In accordance with the present invention, the fuel cell and the gasifier 
are arranged in a novel combination wherein the steam and carbon dioxide 
generated by the electrochemical reaction at the anode in the fuel cell 
are utilized in a catalytic coal or coal char gasifier for providing the 
steam, reducing atmosphere and the heat utilized in the endothermic 
reaction therein for providing the fuel gases used in the fuel cell 
reaction. The coal gasification and fuel cell system of the present 
invention comprises in combination, a coal gasification means for 
endothermically reacting coal or coal char in the presence of a catalyst 
and steam in a reducing or oxygen-free atmosphere for producing a gaseous 
product stream primarily containing carbon monoxide, carbon dioxide and 
hydrogen. The gasification means are coupled by conduit means to anode 
means and cathode means of a molten carbon fuel cell means. Gas separating 
means are disposed along the conduit means for receiving the gaseous 
product stream and separating the carbon dioxide from the hydrogen. The 
portion of the conduit means between the gas separating means and the fuel 
cell means comprise first and second conduit means. The first conduit 
means are used for conveying hydrogen separated in the gas separating 
means to the anode means and while the second conduit means are for 
conveying carbon dioxide separated in the gas separating means to the 
cathode means. The carbon dioxide and hydrogen introduced into the fuel 
cell means by the conduit means effect an electrochemical reaction in the 
fuel cell means for producing an electrical output while generating 
reaction products including steam at the anode means. Further conduit 
means couple the anode means to the gasification means for conveying steam 
generated in the fuel cell means to the gasification means for providing 
steam and heat utilized for the endothermic reaction in the gasification 
means. In addition to the steam generated at the anode means in the fuel 
cell means, a significant volume of carbon dioxide is also generated at 
the anode means by the electrochemical reaction. This carbon dioxide gas 
is conveyed along with the steam to the coal gasification means for 
providing heat and the reducing or oxygen-free atmosphere utilized in the 
gasification means for the endothermic reaction. The coal or char 
gasification means provides a gaseous product stream containing carbon 
dioxide and hydrogen at a temperature in the range of about 1100.degree. 
F. to about 1300.degree. F. and a pressure in the range of above one 
atmosphere to about six atmospheres. The gasifier is preferably operated 
at a pressure corresponding to the pressure in the fuel cell. When the 
product gases are maintained at essentially these temperatures and 
pressures the gases can be introduced into the fuel cell without further 
heating or pressurization. However, in the event the temperature or the 
pressure of the product gases are excessively reduced in the gas clean-up 
operation or the gas separating operation the gasification means can be 
operated at a higher temperature or pressure to overcome the reductions. 
Preferably, the losses in temperature and/or pressure in product gases is 
held to a minimum in order to maintain a high level of efficiency for the 
overall system. The temperature of the reaction gases discharged from the 
fuel cell means are higher by as much as about 250.degree. to about 
275.degree. F. than the temperature of the reactant gases introduced into 
the fuel cell means due to the heat generated during the electrochemical 
reaction in the fuel cell means. 
One of the principal products of the electrochemical reaction in the fuel 
cell means is water at the anode means which is in the form of saturated 
steam and free water at the pressures and temperatures employed in the 
operation of the fuel cell means. The CO in the gaseous products are 
preferably conveyed to the anode means where the CO reacts with the water 
in the presence of steam to form H.sub.2 and CO.sub.2. In order to assure 
that the quantity of water used in the gasification means in the form of 
steam and present in the product gases discharged from the gasification 
means is maintained at a level wherein satisfactory operation of the 
achieved, the excess water must be removed from the discharge stream of 
reaction gases before the gases are introduced into the gasification 
means. 
The stream of reaction products generated at the cathode means by the 
electrochemical reaction contains carbon dioxide, a portion of which may 
be recycled into the fuel cell means along with the carbon dioxide in the 
above mentioned second conduit means to assure and maintain the 
concentration of the carbon dioxide an acceptable level at the cathode 
means. The temperature of this makeup gas stream can be readily regulated 
and controlled by cooling or heating to assure that the reaction 
temperature at the cathode means is maintained at a satisfactory value. 
The oxygen utilized in the electrochemical reaction at the cathode means in 
the fuel cell means is preferably provided by mixing air with the stream 
of carbon dioxide discharged from the gas separating means. The volume of 
air mixed with the carbon dioxide must be sufficient to provide the oxygen 
requirements for the reaction at the cathode means as described above. 
This stream of air is preferably passed in heat exchange relationship with 
the hot stream of carbon dioxide being discharged from the fuel cell 
before it is admixed with the stream of carbon dioxide to selectively heat 
and maintain the air-carbon dioxide mixture at a temperature desired for 
the operation of the fuel cell means. With air being used as the source 
for the oxygen used in the electrochemical reaction, the stream of 
reaction gases discharged at the cathode means will also include some 
nitrogen. The presence of nitrogen in the fuel cell at relatively low 
concentrations is not harmful. However, if the concentration of nitrogen 
in the fuel cell means tends to become excessive, the nitrogen can be 
separated from the makeup stream of carbon dioxide by using a ceramic 
membrane such as in the gas separating means. The major portion of the 
reaction gases discharged at the cathode means are utilized in the heat 
exchanger for the air and are then passed through a suitable power 
generation system such as a turbine or the like for the recovery of heat 
energy remaining in the gas stream. 
The hydrogen and or the carbon dioxide-air mixture may require 
pressurization in order to be introduced into the fuel cell means at a 
selected pressure within the aforementioned operating range. Also, the 
stream of steam and carbon dioxide conveyed from the fuel cell means to 
the gasification means is pressurized to provide the catalytic 
gasification a the pressure necessary for operating the fuel cell means. 
Other and further objects of the invention will be obvious upon an 
understanding of the illustrative embodiments and method about to be 
described or will be indicated in the appended claims, and various 
advantages not referred to herein will occur to one skilled in the art 
upon employment of the invention in practice.

DETAILED DESCRIPTION OF THE INVENTION 
With reference to the accompanying drawing the molten carbonate fuel cell 
and gasifier combination of the present invention is an arrangement 
capable of operating in a more efficient manner than previously known fuel 
cell-gasifier arrangements. In the drawing a conventional molten carbonate 
fuel cell is generally shown at 10 and comprises an anode 12 and a cathode 
14 with a body of electrolyte 16 therebetween. The anode 12 may be formed 
of any suitable commercially available material such as porous nickel. The 
cathode 14 may also be formed of a suitable available material such as 
nickel oxide. The electrolyte 16 may be of any suitable material such as 
an alkali metal compound and lithium aluminate. The anode, cathode and 
electrolyte are normally maintained in a housing such as generally shown 
at 18. The molten carbonate fuel cells are well known for their operation 
at temperatures of about 1050.degree. to 1150.degree. F. and at pressures 
in the range of about 1.1 to about 6 atmospheres. The fuel cell as 
generally mentioned above generates electricity by an electrochemical 
reaction wherein hydrogen, carbon dioxide and oxygen are the reacting 
gases. These gases are introduced into the fuel cell at the appropriate 
electrodes such as the hydrogen at the anode 12 and carbon dioxide and 
oxygen at the cathode 14 for enabling the above described electrochemical 
reaction to occur for effecting the production of electrical power. 
A coal or coal char gasifier utilized to provide the electrodes 12 and 14 
of the fuel cell 10 with the reactant hydrogen and carbon dioxide gases is 
generally shown at 22. This gasifier 22 is a catalytic-type reactor 
wherein an endothermic reaction is achieved in an essentially oxygen-free 
or reducing atmosphere with coal or char in the presence of a catalyst, 
steam and external source of heat. The endothermic reaction pyrolyzes 
essentially all of the coal or char to provide a stream of product gases 
which are rich in hydrogen, carbon dioxide and carbon monoxide and contain 
lesser quantities of impurities such as hydrogen sulfide and carbonyl 
sulfide. As shown, the coal or char, in particulate form, is introduced 
into the gasifier 28 through line 24. The catalyst may be of any suitable 
type such as potassium/calcium oxides or potassium/nickel oxides with or 
without pyrites and may be combined with the coal or char prior to the 
introduction thereof into the gasifier 22. Alternatively, the catalyst may 
be introduced into the gasifier 22 through a separate line (not shown). It 
may be also desirable to introduce into the gasifier 22 a calcium compound 
such as CaO or CaCO.sub. 3 to provide adsorption of the sulfur as well as 
some additional catalytic activity during the gasification operation. The 
endothermic reaction within the gasifier 22 is achieved by introducing the 
coal or coal char and a catalyst such as mentioned above into the gasifier 
22 while introducing a stream of steam and carbon dioxide through a 
separate feed line 25, as will be discussed in detail below. This stream 
of steam and carbon dioxide provides the high-temperature heat source, the 
steam and the reducing atmosphere necessary to effect the endothermic 
reaction of the coal or char in the gasifier 22. The solid reaction 
products including spent catalyst resulting from the endothermic reaction 
are discharged from the gasifier 22 through line 26 at the base of the 
gasifier 22. The gaseous reaction products are discharged from the 
gasifier 22 through a line or conduit 28 at the top of the gasifier 22 
with these gaseous products preferably being at a temperature in the range 
of about 1050.degree. to about 1150.degree. F. The gasifier 22 is 
preferably operated at a pressure greater than atmospheric and in a range 
of about 1.1 to about 6 atmospheres. These ranges of temperature and 
pressure correspond to those at which the molten carbonate fuel cell will 
satisfactorily operate. However, if some reduction in the temperature or 
pressure is experienced in the gaseous product stream between the gasifier 
22 and the fuel cell 10 such as caused the treatment of the gaseous 
products for the removal of solid particulates and sulfur and/or the 
separation of the reactant gases for use in appropriate electrodes in the 
fuel cell 10, then the gasifier 22 can be operated at higher temperatures 
and/or pressures to satisfy the requirements of the fuel cell. 
The conduit 28 conveys the stream of fuel gas or gaseous reaction products 
from the gasifier 22 into a hot gas cleanup system generally shown at 32 
wherein essentially all solid particulates and sulfur compounds are 
removed from the gas stream prior to the separation of the hydrogen and 
carbon dioxide from the gaseous stream for introduction into the fuel cell 
10 at appropriate electrodes. The removal of essentially all the sulfur 
from the product gas stream is necessary since sulfur concentrations 
greater than about 1-5 ppm have been found to be detrimental to the 
operation of the fuel cell. The removal of the sulfur compounds is 
preferably achieved in any suitable manner while maintaining the gaseous 
product stream in the aforementioned temperature and pressure range. For 
example, a bed of zinc ferrite or other solid adsorbent may be used to 
remove sulfur compounds from the gaseous product stream. 
Essentially all of the solid particulate matter in the product gases must 
also be removed from the reactant gases used in the fuel cell 10. It has 
been found that sufficient particulate material must be removed to provide 
the gaseous stream with a maximum amount of particulate material of less 
than about one milligram per liter of gas with this particulate materials 
being of a size less than about 10 micrometers. The apparatus expected to 
provide satisfactory removal of particulate material from hot gas streams, 
preferably without excessively decreasing the temperature or pressure of 
the gaseous products include cyclones, ceramic filters, and the like. 
The product gases once stripped of the sulfur and particulate material are 
then conveyed via conduit 34 to a gas separating apparatus generally shown 
at 36 which is required for separating the carbon dioxide from the 
hydrogen in the product gases for separate conveyance to appropriate 
electrodes in the fuel cell 10. The separation of the carbon dioxide from 
the hydrogen in the product gas stream should be achieved in a manner with 
little or no losses in temperature or pressure in both of the separated 
gas streams even though some pressure reductions may be experienced in one 
of the separated gas streams. For example, ceramic membranes formed of a 
material such as aluminum oxide have been found to be useful for 
separating CO.sub.2 from H.sub.2 and other lighter gases such as CO in the 
gaseous products. These ceramic membranes are selectively porous to 
CO.sub.2 to provide for the separation of the CO.sub.2 from essentially 
all the other gases present in the gaseous products. However, by using 
such membranes the pressure of the separated stream of CO.sub.2 is reduced 
to or essentially to atmospheric pressure as it is separated in the 
membrane. The pressure of the CO.sub.2 must be increased to a selected 
pressure in the operating range before it can be introduced into the fuel 
cell 10. The stream of CO.sub.2 is conveyed from the separator 36 through 
a separate line 40 to the cathode 14 of the fuel cell 10. 
In accordance with the present invention, a stream of air in line 42 is 
combined with the CO.sub.2 in line 40 in a sufficient concentration to 
provide the oxygen necessary for effecting the portion of the 
electrochemical reaction at the cathode 14. Inasmuch as the CO.sub.2 
stream may undergo a pressure loss to or about to atmospheric pressure in 
the separator 36 the air stream in conduit 42 may be admixed with the 
stream of CO.sub.2 without being pressurized. However, if the pressure in 
the stream of CO.sub.2 from the separator 36 is not at or near atmospheric 
pressure, a simple compressor (not shown) may be employed to pressurize 
the air stream to a value corresponding to that of the CO.sub.2. In the 
embodiment illustrated in the drawing, the stream of CO.sub.2 from the 
separator 36 is reduced to atmospheric pressure and is mixed with air at 
the same pressure. This mixture of CO.sub.2 and air is pressurized in a 
suitable compressor such as shown at 44 to a pressure slightly less than 
that desired for use in the operation of the fuel cell 10. This 
pressurized mixture is conveyed into a further compressor 46 connected in 
conduit 40 downstream of compressor 44 for boosting the pressure of the 
mixed gas stream to the pressure desired for use in the fuel cell 10. The 
utilization of this two-stage compressor arrangement is advantageous for 
the introduction of additional CO.sub.2 into line 40 when the 
concentration of CO.sub.2 from the separator 36 is insufficient to provide 
the desired electrochemical reaction in the fuel cell. In such an instance 
a portion of the CO.sub.2 generated by the reaction at the cathode 14 of 
the fuel cell 10 and discharged from the fuel cell 10 through line 48 may 
be admixed with the CO.sub.2 -air mixture at a location between the 
compressors 44 and 46 for recycling purposes in order to provide the fuel 
cell with appropriate concentration of CO.sub.2. By introducing the 
recycled CO.sub.2 via conduit 50 into conduit 40 at a location between the 
compressors the discharge pressure from the first compressor 44 can be 
adjusted so as to correspond with the pressure of the recycled CO.sub.2 in 
line 50. Another advantage to the utilization of this CO.sub.2 recycling 
arrangement is that a suitable heat exchanger generally shown at 52 may be 
placed in line 50 to regulate the temperature of the CO.sub.2 -air mixture 
being conveyed into the fuel cell. For example, the heat exchanger 52 may 
be used to cool or heat the CO.sub.2 -air mixture to assure that the 
operating temperature of the fuel cell 10 is maintained within the desired 
range. A suitable valve 54 is shown in line 50 for regulating the flow of 
the makeup CO.sub.2 into line 40. 
While the drawing and the above description is directed to an embodiment 
wherein the CO.sub.2 is separated from the H.sub.2, it will appear clear 
that a gas separating mechanism which is capable of preferentially 
separating the H.sub.2 from the other gaseous constituents in the product 
gases may be readily utilized in place of the CO.sub.2 separating 
mechanism 36. The preferential separation of H.sub.2 may be achieved by 
membranes, electrochemical means, hollow fibers of alunina or silica, or 
prsssure swing adsorption. If a pressure drop occurs in the separated 
stream of H.sub.2 due to the separation process, a suitable compressor 
(not shown) may be placed in the line 28 to pressurize the H.sub.2 to the 
appropriate pressure for fuel cell use. Also, in such a separation the 
stream of CO.sub.2 may be at or near the desired pressure for use in the 
fuel cell. In such an event, the air stream to be mixed with the CO.sub.2 
may be pressurized to a pressure corresponding to that of the CO.sub.2 
stream by placing a compressor in the air conduit. If further 
pressurization of the mixture, with or without the makeup CO.sub.2, a 
two-stage compressor arrangement such as shown in the drawing may be used. 
The embodiment shown in the drawing is the preferred embodiment with 
respect to the separation of the reactant gases in that the CO in the 
gaseous products remains with the H.sub.2 and is conveyed into the fuel 
cell at the anode 12 where the water-gas reaction (H.sub.2 
O+CO.revreaction.H.sub.2 +CO.sub.2) takes place in the presence of steam 
without the expenditure of energy to increase the concentration of 
reactant gases for the fuel cell 10 and the gasifier 22. In the event the 
H.sub.2 is preferentially separated the CO must be then separated from the 
CO.sub.2 in any suitable manner such as with a ceramic membrane and 
combined with the H.sub.2 feed to the anode 12. 
The carbon dioxide stream discharged from the cathode 14 through line 48 
may also be used to heat the stream of air in line 42 prior to being mixed 
with the CO.sub.2 in line 40. To accomplish this heating step a suitable 
heat exchanger with appropriate controls as generally shown at 56, may be 
utilized in lines 42 and 48. The air stream thus heated by the CO.sub.2 
stream in line 48 assures that the CO.sub.2 -air mixture conveyed into the 
cathode 14 is at the desired temperature. The heat energy remaining in the 
carbon dioxide after passing through the heat exchanger 56 may be 
extracted in a suitable turbine as generally shown at 58 and which can be 
coupled to a power generator for the purpose of generating electricity for 
further increasing the overall efficiency of the fuel cell system. The gas 
stream discharged through line 48 from the cathode will contain nitrogen 
primarily derived from the air in the air-CO.sub.2 mixture being conveyed 
to the cathode through line 40. The concentration of the nitrogen is 
usually insufficient to detract from the operation of the fuel cell when 
recycled with the makeup CO.sub.2. 
The electrochemical reaction in the fuel cell 10 generates reaction 
products at the anode 12 that are formed primarily of water as steam and 
CO.sub.2. In accordance with a primary feature of the present invention 
these reaction products from the anode 12 are introduced into the gasifier 
22 to provide the heat, steam and reducing atmosphere necessary to effect 
the reactant gas-producing endothermic reaction with coal or char in the 
presence of a catalyst. This stream of reaction products from the anode 
12, like the stream of reaction products from the cathode 14, is at a 
temperature higher than that of the reactant gases entering the electrodes 
12 and 14 of the fuel cell 10. The temperature of the reaction gases from 
the fuel cell 10 is in the range of about 1300.degree. to about 
1375.degree. F., which is about 250.degree. to 275.degree. F. hotter than 
the reactant gases entering the fuel cell 10. Before the stream of 
reaction gases from the anode 12 of the fuel cell are introduced in the 
gasifier 22 through conduit 62 they are first conveyed into a suitable 
water removal system 64 such as a condenser, drying bed or the recycle of 
purge stream from anod effluent through a catalytic combustor to the 
cathode and out through a bottoming cycle through line 58. In the water 
removal system 64 excess water in the steam is removed and discharged 
through line 66. The quantity of excess water that has to be removed from 
the reaction products from the anode 12 depends upon several factors such 
as the volume of steam needed to efficiently effect the endothermic 
reaction in the gasifier 22 and the volume of steam needed for the 
operation of the fuel cell. Normally, the electrochemical reaction in the 
fuel cell generates more water than required to the endothermic reaction 
in the gasifier 22. This excess water is removed from the system through 
the water extracting mechanism 64. The steam and CO.sub.2, which is 
preferably maintained at a temperature in the range of about 1300.degree. 
to 1375.degree. F. during this water removal process, is conveyed through 
line 68 to a suitable compressor 70 where the steam and carbon dioxide are 
pressurized to a pressure corresponding to that desired for use in the 
gasifier 22 and the fuel cell 10. As pointed out above the gasifier 22 may 
be operated at a higher pressure than that utilized in the operation of 
the fuel cell to assure that any pressures losses in the reactant gas 
clean up and gas separating mechanisms are adequately compensated for. 
This pressurized charge of steam and carbon dioxide is then conveyed into 
the gasifier through line 25 to provide and support the endothermic 
reaction with the coal or char in the presence of a catalyst. This 
compressors 70 as well as the compressors 44 and 46 may be coupled to 
turbines driven by a portion of the CO.sub.2 being discharged from the 
cathode 14 through line 48. 
It will be seen that the present invention provides a novel combination of 
a gasifier with a molten carbonate fuel cell wherein the overall 
efficiency of the fuel cell is greatly enhanced since the source of 
reactant gases provided to the fuel cell are produced in a gasifier which, 
in turn, is provided with the reaction gases from anode of the fuel cell 
to provide the steam, the reducing atmosphere and the heat needed in the 
gasifier to support and effect a reactant gas-producing endothermic 
reaction with coal or char in the presence of a catalyst.