JP2001065364A - Power generating system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an efficient power generating system at a low cost while biomass of organic waste, organic sludge, livestock waste, municipal refuse, etc., and low quality fossil fuel of waste of waste plastic or the like, coal, heavy oil, etc., are used as fuel. SOLUTION: This power generating system 20 is provided with a gasifying device 4 making introduced fuel 10 react on water 11 to generate gasified gas. A separation device 5 separating gasified gas, left solid component, and left water component is connected to the gasifying device 4. A power generating set 6 generates electric power by burning the gasified gas separated by the separation device 5. Exhaust gas of the power generating set 6 is guided to the gasifying device 4 by an exhaust gas pipe 16. The gasifying device 4, utilizing heat of exhaust gas guided by the exhaust gas pipe 16, makes the fuel 10 react on the water 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power generation system for generating power using biomass such as organic waste, organic sludge, livestock waste (livestock dung), and municipal waste as fuel.

[0002]

2. Description of the Related Art Livestock waste such as manure discharged from livestock such as cattle, pigs and chickens generates methane gas in the course of digestion treatment by methane fermentation. There is a power generation system that collects this methane gas and uses it for power generation via a prime mover.

[0003] Regarding such a conventional power generation system,
This will be described with reference to FIG. FIG. 5 is a schematic diagram of a methane fermentation / power generation system using livestock waste.

[0005] The power generation system shown in FIG. 5 includes a receiving tank 37 into which manure and diluting water as livestock waste are introduced, and a digestion tank 38 connected to the receiving tank 37. Digestion tank 3
Numeral 8 generates digestion gas from the excrement and dilution water sent from the receiving tank 37 by fermentation (methane fermentation).

A gas pipe 46 and a residue discharge pipe 47 are connected to the digestion tank 38. The gas pipe 46 is connected to the gas engine generator 43 via the gas holder 41 and the desulfurization tower 42.
Extending to A dehydrator 39 is connected to the residue discharge pipe 47. A drain pipe 48 for discharging the dehydrated cake and a drain pipe 49 for discharging the dehydrated desorbed liquid are connected to the dehydrator 39. The drainage pipe 49 is connected to the sewage treatment apparatus 40.

[0006] Such a power generation system operates as follows.

[0007] The collected manure is once stored in a receiving tank 37 together with dilution water. Then, when desired, it is sent to the digestion tank 38 and fermented.

The digestion gas generated by the fermentation is supplied to a gas pipe 4
After being sent to a desulfurization tower 42 through which the sulfur content is removed, it is sent to a gas engine generator 43 for combustion and used for power generation. Excessive digestive gas is stored in gas holder 41
Stored temporarily.

[0009] The residue after fermentation is sent to a dehydrator 39 through a residue discharge pipe 47 to be dehydrated to a water content of about 70%.
The cake is released as a dehydrated cake from the discharge pipe 48 and is made into fertilizer at a composting facility (not shown). The dewatered desorbed liquid squeezed out by the dehydrator 39 is sent to a sewage treatment apparatus 40 via a drain pipe 49, where it is treated with water and then discharged to a river or the like.

[0010] In the power generation system based on methane fermentation shown in FIG. 5, energy recovery of 10 to 150 kWh / t feces is realized by using digestive gas as fuel for the gas engine generator 43.

[0011]

In the power generation system shown in FIG. 5, a large amount of dehydration / desorption liquid is generated. Since a large-scale sewage treatment facility is required for the treatment of the dehydration / desorption liquid, there is a problem that equipment costs are increased. Further, there is a problem that the energy efficiency of the entire system is not good because a large amount of energy is required for processing the dehydration / desorption liquid.

[0012] The present invention has been made in view of the above points, and includes organic waste, organic sludge, livestock waste,
It is an object of the present invention to use biomass such as municipal solid waste, waste such as waste plastic, low-quality fossil fuel such as coal and heavy oil as a fuel, and to provide an efficient power generation system at low cost.

[0013]

SUMMARY OF THE INVENTION The present invention provides a gasifier for reacting introduced fuel with water to generate a gasified gas, a gasifier connected to the gasifier, and a gasified gas and residual solid content. A separation device for separating residual moisture, and connected to the separation device,
A power generator that generates power by burning the gasified gas separated by the separator, and an exhaust gas pipe connected to the power generator and guiding the exhaust gas of the power generator to the gasifier, the gasifier includes:
This is a power generation system characterized in that fuel and water are reacted by utilizing heat of exhaust gas guided by an exhaust gas pipe.

According to the present invention, since the gasifier uses the heat of the exhaust gas guided by the exhaust gas pipe to react the fuel with water, an efficient power generation system is provided at low cost. be able to.

Further, the present invention provides a liquefier for reacting introduced fuel and water to generate a liquid fuel, and a separator connected to the liquefier for separating the liquid fuel, residual solids and residual moisture. A power generation device connected to the separation device and burning the liquid fuel separated by the separation device to generate power, and an exhaust gas pipe connected to the power generation device and guiding exhaust gas of the power generation device to the liquefaction device, Is a power generation system characterized in that fuel and water are made to react using heat of exhaust gas guided by an exhaust gas pipe.

According to the present invention, the liquefaction apparatus utilizes the heat of the exhaust gas guided by the exhaust gas pipe to react fuel with water, so that an efficient power generation system can be provided at low cost. Can be.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a power generation system according to a first embodiment of the present invention. As shown in FIG. 1, the power generation system 20 according to the first embodiment of the present invention includes:
There is provided a gasification device 4 for reacting the introduced fuel 10 and water 13 to generate a gasification gas.

The gasifier 4 is connected to the gasifier 4 through a connection pipe 18.
Separation device 5 for separating gasified gas, residual solids and residual moisture
Is connected.

A gas generator 6 for generating electricity by burning the gasified gas separated by the separator 5 is connected to the separator 5. The gas power generator 6 includes a compressor 6a, a combustor 6
b, a gas turbine 6c and a generator 6d. The gasification gas is supplied to the combustor 6b via the pipe 17.

The gas turbine 6c of the gas generator 6 includes:
An exhaust gas pipe 16 for guiding the exhaust gas to the gasifier 4 is connected. Then, the gasifier 4 uses the heat of the exhaust gas guided by the exhaust gas pipe 16 to generate the fuel 10 and the water 13.
To react with. The gasifier 4 of the present embodiment is configured as an exhaust heat recovery type low temperature gasifier,
It has a reaction tube 4a constituted by a plurality of tubular members to increase the surface area for heat exchange, and an exhaust gas chamber 4c formed around the reaction tube 4a.

In the present embodiment, the introduction of the fuel 10 and the water 13 into the reaction tube 4a of the gasifier 4
And, through the slurry pump 2, it is performed in a state of a water slurry. That is, in the fuel supply device 1, the fuel 10 and the water 13 are mixed in advance to form a water slurry, and the water slurry is
4 to the gasifier 4.

In the present embodiment, the fuel 10 is biomass such as organic waste, organic sludge, livestock waste, and municipal waste.

In the present embodiment, in the fuel supply device 1, sodium hydroxide 13, a nickel-based catalyst containing nickel and an alkali metal catalyst 12 are mixed together with the fuel 10 and water 11. Sodium hydroxide 13 may be potassium hydroxide or the like.

Further, a portion of the pipe 14 on the way from the slurry pump 2 to the reaction tube 4a and a connection tube 18 connecting the reaction tube 4a and the separation device 5 form the heat exchanger 3. High-temperature substances (gasified gas +
The thermal energy of the residual solid content + residual moisture is transferred to a substance (fuel 10 + water 11 + sodium hydroxide 13) passing through the pipe 14.
+ Catalyst 12).

Further, to the separation device 5 of the present embodiment, a recirculation pipe 15 for recirculating the residual water separated by the separation device 5 to the fuel supply device 1 is connected. On the other hand, a discharge pipe 19 for discharging the residual solids separated by the separation device 5 is also connected to the separation device 5.

The gasifier 4 according to the present embodiment has a fuel 10
And water 11 at a temperature of 200-500 ° C. and 10-60
The reaction is performed at a pressure of 0 atm, preferably 100 to 400 atm. Further, the gasifier 4 of the present embodiment is capable of bringing the water 11 into a state of pressurized hot water, supercritical water, or subcritical water.

Next, the operation of the present embodiment having such a configuration will be described.

Fuel 10, water 11, sodium hydroxide 13
When the catalyst 12 and the catalyst 12 are introduced into the fuel supply device 1, the fuel supply device 1 mixes them to form a water slurry. This water slurry is supplied to the slurry pump 2 for 10-6.
The pressure is increased to about 00 atm, preferably about 100 to 400 atm, more preferably about 200 atm, and sent to the reaction tube 4 a of the gasifier 4 via the pipe 14. The water slurry is preheated by the action of the heat exchanger 3 when passing through the pipe 14.

The gasifier 4 includes an exhaust gas chamber 4c.
Utilizing the heat of the exhaust gas filling the inside, the water slurry sent into the reaction tube 4a is heated, and the fuel 10 and the water 11 react. At this time, the fuel 10 and the water 11 are separated by 500% by the heat of the exhaust gas (the temperature of the exhaust gas is about 600 ° C. as described later).
When the temperature is raised to a temperature of about ° C., the water 11 can be in a state of pressurized hot water, supercritical water or subcritical water. Biomass can be converted to gaseous fuel at such a relatively low temperature, and the conversion reaction proceeds rapidly especially in pressurized hot water, supercritical water, and subcritical water.

The reaction between the fuel 10 and the water 11 generates a gasified gas mainly composed of methane, hydrogen, carbon monoxide, carbon dioxide and the like. The gasified gas, residual solids remaining without reacting, and residual moisture are converted into a reaction tube 4a at a high temperature.
From the pipe 18. Then, after the water slurry is preheated by the heat exchanger 3 to lower the temperature, the separation device 5
Sent to

The separation device 5 separates the gasified gas, the remaining solid content, and the remaining moisture. Then, the gasification gas is supplied to the combustor 6b via the pipe 17. On the other hand, the residual water is returned to the fuel supply device 1 through the reflux pipe 15 and
The remaining solids are discharged via. The remaining solids include, in addition to the unreacted organic matter of the fuel 10, sodium sulfide (which has become insoluble in water and precipitates), which is a reaction product of sulfur and sodium hydroxide 13, and biomass. Inorganic solids and the like.

The gas generator 6 burns gasified gas supplied to the combustor 6b together with air compressed by the compressor 6a, and rotates the gas turbine 6c and the generator 6d to generate power. The hot gas turbine exhaust gas after combustion is 6
It has a temperature of about 00 ° C., is sent to the exhaust gas chamber 4c of the gasifier 4 via the exhaust gas pipe 16, and is used for heating water slurry in the reaction tube 4a.

As described above, according to the present embodiment, the gasifier 4 reacts the fuel 10 with the water 11 by using the heat of the exhaust gas guided by the exhaust gas pipe 16. Thus, an efficient power generation system can be provided at low cost.

In particular, since the reaction tube 4a of the gasifier 4 is composed of a plurality of tubular members, the heat exchange efficiency of the gasifier 4 is excellent, and as a result, the efficiency of the power generation system 20 is improved. Furthermore, such a configuration is less expensive than a spouted bed reactor or a fluidized bed reactor. But water 11
Can be in a state of pressurized hot water, supercritical water or subcritical water, so that the gasifier 4 and the connecting pipe 18 need to be configured to withstand such severe conditions.

Since the fuel 10 and the water 11 are supplied in the form of a water slurry, even relatively low-temperature exhaust gas heat can be effectively used for generating gasified gas.

In this embodiment, since the water 11 is recirculated through the recirculation pipe 15, the recirculation flow rate is appropriately adjusted,
The fuel / water ratio can be a value suitable for the reaction.

In this embodiment, the fuel 10 and the water 1
Since the catalyst 12, for example, a nickel-based catalyst and an alkali metal catalyst are mixed in addition to 1, the gasification gas generation reaction is smoothly realized. It is also possible to charge the catalyst in advance in the gasifier instead of supplying the catalyst together with the fuel or water.

Further, in the present embodiment, since sodium hydroxide 13 is mixed in addition to fuel 10 and water 11, sulfur contained in biomass is converted into gasification gas generation reaction in the form of sodium sulfide. It can be removed as residual solids.

In the power generation system according to the present embodiment, the gas power generator 6
Is a high calorie gas (eg natural gas, LNG, LP
G, city gas, propane gas, etc.) are preferably introduced.

As the fuel 10, besides biomass, waste such as waste plastic, low-quality fossil fuel such as coal and heavy oil can be used.

Next, a power generation system according to a second embodiment of the present invention will be described with reference to FIG. FIG. 2 shows the second
1 is a schematic configuration diagram of a power generation system according to an embodiment.

As shown in FIG. 2, in the power generation system 20 according to the present embodiment, a calcium oxide pipe 21 for introducing calcium oxide into the connection pipe 18 is connected to the connection pipe 18. On the downstream side of the calcium tube 21, a heat insulating material is wound to form an adiabatic reactor 22. The adiabatic reactor 22 reacts the carbon dioxide passing through the portion with the calcium oxide introduced from the calcium oxide tube 21, and the unreacted fuel 10
And the reaction of water 11 is promoted.

The discharge pipe 19 is connected to a combustion furnace 23 for burning the residual solids separated by the separator 5 to decompose calcium carbonate contained in the residual solids. A part of the gasified gas is supplied to the combustion furnace 23 from the separation device 5, and a part of the gas turbine exhaust gas is also supplied.

Further, only the alkali metal catalyst 26 is supplied without supplying the nickel-based catalyst to the fuel supply device 1.

The other configuration is substantially the same as that of the power generation system of the first embodiment shown in FIG. In the second embodiment, the same parts as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description is omitted.

In the present embodiment, the pressure of the water slurry is raised to about 300 atm by the slurry pump 2. This is because the temperature of water is further increased by the heat of reaction in which calcium oxide and carbon dioxide react to change into calcium carbonate, and unless pressure is increased, water vapor is generated.

In this embodiment, carbon dioxide and calcium oxide react in the adiabatic reactor 22, and the unreacted fuel 10 and water 1
1 is further heated to about 700 ° C. to further promote a gasification gas generation reaction.

In this case, the residual solids also include calcium carbonate generated by the reaction between carbon dioxide and calcium oxide. The residual solids are burned by the combustion furnace 23 together with a part of the gasified gas and a part of the gas turbine exhaust gas. By this heat of combustion, calcium carbonate is decomposed and calcium oxide is recovered. The recovered calcium oxide is sent to, for example, the calcium oxide tube 21 again.

According to the present embodiment, by utilizing the reaction between carbon dioxide and calcium oxide, it is possible to heat unreacted fuel 10 and water 11 to a temperature equal to or higher than the temperature of the exhaust gas. Generation efficiency is improved.

Further, since it is not necessary to use an expensive nickel catalyst and calcium oxide is inexpensive, an efficient power generation system can be realized at lower cost.

Next, a power generation system according to a third embodiment of the present invention will be described with reference to FIG. FIG.
1 is a schematic configuration diagram of a power generation system according to an embodiment.

As shown in FIG. 3, in the power generation system 20 of the present embodiment, the gasifier 4 is replaced with a liquefier 24, and the gas generator 6 is replaced with a diesel generator 25. The liquefier 24 is substantially the same as the gasifier 4,
It has a reaction tube 24a formed of a tubular member and an exhaust gas chamber 24c provided around the reaction tube 24a. Also,
The exhaust gas from the diesel power generator 25 is introduced into the exhaust gas chamber 24c.

In the present embodiment, the alkali metal catalyst 26
Is supplied to the fuel supply device 1. The separation device 5 separates the liquid fuel, residual solids, and residual moisture generated in the liquefaction device 24.

Other configurations are substantially the same as those of the power generation system of the first embodiment shown in FIG. In the third embodiment, the same parts as those in the first embodiment shown in FIG. 1 are denoted by the same reference numerals, and detailed description is omitted.

The power generation system 20 according to the present embodiment operates as follows.

Fuel 10, water 11, sodium hydroxide 13
When the alkali metal catalyst 26 is introduced into the fuel supply device 1, the fuel supply device 1 mixes them to make a water slurry. This water slurry is pressurized to about 200 atm by the slurry pump 2 and sent to the reaction tube 24 a of the liquefaction device 24 via the pipe 14. Water slurry
When passing through the pipe 14, it is preheated by the action of the heat exchanger 3.

The liquefaction apparatus 24 includes an exhaust gas chamber 24.
The water slurry sent into the reaction tube 24a is heated by utilizing the heat of the exhaust gas filled in c, and the fuel 10 and the water 11 are reacted. At this time, the temperature of the fuel 10 and the water 11 is raised to a temperature of about 450 ° C. by the heat of the exhaust gas, and the water 11 can be in a state of pressurized hot water, supercritical water, or subcritical water. Biomass can be converted to a liquid fuel at such relatively low temperatures, especially pressurized hot water, supercritical water,
In subcritical water, the conversion reaction proceeds quickly.

In this case, due to the action of the alkali metal catalyst 26, the fuel 10 and the water 13 react, and a part of the organic components in the water slurry becomes oil (liquid fuel). This oil, the remaining solids remaining without reacting, and the remaining moisture are extruded from the reaction tube 24a to the pipe 18 at a high temperature. Then, the water slurry is preheated by the heat exchanger 3 to lower the temperature, and then sent to the separation device 5.

The separation device 5 separates the liquefied gas, the residual solid content, and the residual moisture. Then, the liquefied gas is supplied to the diesel power generator 25 via the pipe 17. On the other hand, the residual moisture is circulated to the fuel supply device 1 through the reflux pipe 15, and the residual solid is discharged through the discharge pipe 19. The remaining solids include, in addition to the unreacted organic matter of the fuel 10, sodium sulfide (which has become insoluble in water and precipitates), which is a reaction product of sulfur and sodium hydroxide 13, and biomass. Inorganic solids and the like.

The diesel power generator 25 generates power by burning oil. Exhaust gas after combustion is about 500 ° C (60
Is it not 0 ° C? ), And is sent to the exhaust gas chamber 24c of the liquefaction unit 24 via the exhaust gas pipe 16 to heat the water slurry in the reaction tube 24a.

As described above, according to the present embodiment, the liquefaction apparatus 24 uses the heat of the exhaust gas guided by the exhaust gas pipe 16 to cause the fuel 10 and the water 11 to react with each other. An efficient power generation system can be provided at low cost.

In particular, since the reaction tube 24a of the liquefaction apparatus 24 is composed of a plurality of tubular members, the liquefaction apparatus 24 is excellent in heat exchange efficiency, and as a result, the efficiency of the power generation system 20 is improved. Furthermore, such a configuration is less expensive than a spouted bed reactor or a fluidized bed reactor. But water 11
Can be in the state of hot pressurized water, supercritical water or subcritical water, so that the liquefier 24 and the connecting pipe 18 need to be configured to withstand such severe conditions.

Since the fuel 10 and the water 11 are supplied in the form of a water slurry, even relatively low-temperature exhaust gas heat can be effectively used for generating oil (liquid fuel).

In this embodiment, the fuel 10 and the water 1
Since the alkali metal catalyst 26 is mixed in addition to 1, the generation reaction of the oil is smoothly realized. Instead of supplying the catalyst together with the fuel and water, it is also possible to charge the catalyst in advance in the liquefier.

In the power generation system according to the present embodiment, it is preferable that the diesel power generator 25 be supplied with a high calorie liquid fuel for stable operation at the time of starting or the like. Instead of the diesel power generator, a gas turbine for liquid fuel can be used.

Next, a power generation system according to a fourth embodiment of the present invention will be described with reference to FIG. FIG.
1 is a schematic configuration diagram of a power generation system according to an embodiment.

As shown in FIG. 4, in the power generation system 20 of the present embodiment, the diesel power generator 25 is replaced with a steam cycle power generator 36, and the exhaust gas chamber 24c of the liquefier 24 is replaced with a steam cycle power generator. It is integrated with 36 combustion chambers (one mode of connection). That is, the oil separated by the separation device 5 is introduced into the exhaust gas chamber 24c of the liquefaction device 24 together with the air, and is directly burned there (by which the exhaust gas naturally fills the exhaust gas chamber 24c). In addition to heating the steam of the steam cycle power generator 36, the water slurry in the reaction tube 24a of the liquefier 24 is heated.

The steam cycle power generator 36 includes a steam turbine 36c, a generator 36d, a condenser 36e, and a pump 36 in addition to a combustion chamber 36b integrated with the exhaust gas chamber 24c.
p, and these are connected by piping to form a cycle.

The other configuration is substantially the same as the power generation system according to the third embodiment shown in FIG. In the fourth embodiment, the same portions as those of the third embodiment shown in FIG. 3 are denoted by the same reference numerals, and detailed description is omitted.

According to the present embodiment, since the oil separated by the separation device 5 is burned in the exhaust gas chamber 24c, the temperature of the water slurry in the reaction tube 24a rises to about 700 ° C. For this reason, the production reaction of oil (liquid fuel) is further promoted, and the efficiency of the entire power generation system is improved.

[0072]

According to the present invention, since the gasifier uses the heat of the exhaust gas guided by the exhaust gas pipe to react the fuel with the water, an efficient power generation system can be manufactured at low cost. Can be provided.

Further, according to the present invention, since the liquefaction apparatus uses the heat of the exhaust gas guided by the exhaust gas pipe to react the fuel with water, an efficient power generation system is provided at low cost. can do.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a power generation system according to a first embodiment of the present invention.

FIG. 2 is a schematic configuration diagram illustrating a power generation system according to a second embodiment of the present invention.

FIG. 3 is a schematic configuration diagram illustrating a power generation system according to a third embodiment of the present invention.

FIG. 4 is a schematic configuration diagram illustrating a power generation system according to a fourth embodiment of the present invention.

FIG. 5 is a schematic configuration diagram showing a conventional power generation system.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Fuel supply apparatus 2 Slurry pump 3 Heat exchanger 4 Gasifier 4a Reaction tube 4c Exhaust gas chamber 5 Separation apparatus 6 Gas power generator 6a Compressor 6b Combustor 6c Gas turbine 6d Generator 10 Fuel (biomass) 11 Water 12 Nickel System catalyst and alkali metal catalyst 13 Sodium hydroxide 14 Pipe 15 Recirculation pipe 16 Exhaust pipe 17 Pipe 18 Connection pipe 19 Discharge pipe 20 Power generation system 21 Calcium oxide pipe 22 Adiabatic heater 23 Combustion furnace 24 Liquefier 24a Reaction pipe 24c Exhaust gas chamber 25 Diesel generator 26 Alkali metal catalyst 36 Steam cycle generator 36b Combustor 36c Steam turbine 36d Generator 36e Condenser 36p Pump

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Kenshi Deshi 2-1, Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Inside the Toshiba Hamakawasaki Plant (72) Inventor Yuko Onoda Ukishima-cho, Kawasaki-ku, Kawasaki-shi, Kanagawa No. 2 F-term in Toshiba Hamakawasaki Plant (reference) 3G081 BA02 BA15 BA18 BB00 BC07 BD00 DA04 DA22 DA23 DA24 4H060 AA02 BB05 CC03 CC18 FF02 GG01

Claims (11)

[Claims] 1. A gasifier for reacting introduced fuel with water to generate a gasified gas, and a separator connected to the gasifier for separating gasified gas, residual solids, and residual moisture. A power generator connected to the separator and burning the gasified gas separated by the separator to generate power, and an exhaust gas pipe connected to the generator and guiding the exhaust gas of the power generator to the gasifier, A power generation system, wherein the gasifier reacts fuel and water using heat of exhaust gas guided by an exhaust gas pipe. 2. The power generation system according to claim 1, wherein a recirculation pipe for recirculating residual moisture separated by the separation device to the gasification device is connected to the separation device. 3. The power generation system according to claim 1, wherein the power generation device is configured to introduce high-calorie gas fuel when the power generation system is started. 4. The power generation system according to claim 1, wherein the gasification device is adapted to introduce a catalyst containing nickel. 5. The power generation system according to claim 1, wherein the gasifier is adapted to introduce sodium hydroxide or potassium hydroxide. 6. A liquefier for reacting introduced fuel with water to generate liquid fuel, a separator connected to the liquefier, for separating liquid fuel, residual solids and residual moisture, and a separator. A power generation device connected to the power generation device and burning the liquid fuel separated by the separation device to generate power; and an exhaust gas pipe connected to the power generation device and guiding exhaust gas from the power generation device to the liquefaction device. A power generation system characterized in that fuel and water are reacted by utilizing heat of exhaust gas guided by the fuel cell. 7. The power generation system according to claim 6, wherein a reflux pipe is connected to the separation device so that residual water separated by the separation device is returned to the liquefaction device. 8. The power generation system according to claim 6, wherein the power generation device is configured to introduce a high-calorie liquid fuel when the power generation system is started. 9. The power generation system according to claim 6, wherein the liquefaction apparatus is adapted to introduce sodium hydroxide or potassium hydroxide. 10. The power generation system according to claim 1, wherein the water reacted with the fuel is in a state of pressurized hot water, supercritical water, or subcritical water. 11. The power generation system according to claim 1, wherein said fuel is biomass.