JP5875067B2 - Fuel gas purification device, power generation system, and fuel synthesis system - Google Patents

Description

  The present invention relates to a fuel gas purification device, a power generation system, and a fuel synthesis system, and in particular, uses a fuel gas obtained by removing, purifying, and purifying unburned components, ash, impurities, etc. contained in a combustible gas. It is useful to apply to cases.

  In recent years, the use of biomass as energy has attracted attention. As a method of using the energy of biomass, a method of directly burning biomass to obtain heat / electric energy, a method of obtaining fuel gas by thermal decomposition, or the like is known. The crude gas obtained by pyrolyzing biomass with a carbonizer or the like contains ash and impurities. Therefore, the fuel gas is purified from the crude gas by removing impurities and the like with the fuel gas purification device.

  As a fuel gas refining device, for example, a porous body is disposed in a container to which a crude gas is supplied, molten carbonate is supplied to the porous body, and the crude gas is circulated through the porous body. Some are purified (see, for example, Patent Document 1).

  However, although the molten carbonate is retained in the pores of the porous body, it gradually falls to the lower part of the container due to its own weight. For this reason, in order to maintain the state by which the molten carbonate was hold | maintained at the porous body, the problem that the frequency which supplies molten carbonate must be raised arises.

  In order to increase the supply frequency of the molten carbonate, it is necessary to have an apparatus configuration in which the molten carbonate collected in the lower part of the container is recovered and supplied again. This complicates the configuration of the fuel gas purification device and increases the cost.

  Moreover, it is possible to make it easy to hold | maintain molten carbonate by making the void | hole of a porous body fine. However, if the pores of the porous body are made fine, the flow resistance of the crude gas is increased. For this reason, making the pores of the porous body fine in order to hold the molten carbonate is not a means that can be practically adopted.

  Such a problem exists not only in the pyrolysis gas derived from biomass but also in the case of removing impurities and the like from the combustible gas.

JP 2010-184972 A

  In view of such circumstances, an object of the present invention is to provide a fuel gas purification device, a power generation system including the fuel gas purification device, and a fuel synthesis system that can more reliably purify the combustible gas with carbonate. .

In order to achieve the above object, a first aspect of the present invention includes a gas purification container into which a combustible gas is introduced, and a porous structure provided in the gas purification container so that the combustible gas flows. And a carbonate supply means for supplying carbonate to the porous structure, wherein the gas purification vessel is obtained by purifying the combustible gas that has flowed through the porous structure by reaction with the carbonate. The porous structure includes a porous body that partitions a plurality of cells, and particles formed from a functional material, and is smaller than the diameter of the particles. The fuel gas purification apparatus, wherein the particles are held inside the cell having an opening diameter, and the functional material is at least one selected from the group consisting of metal oxide, metal, alloy, and carbon. It is in.

  In the first aspect, the state in which the carbonate (or molten carbonate) is held on the surfaces of the porous body and the particles constituting the porous structure and the gap between the porous body and the particles is maintained. . That is, since a sufficient amount of molten carbonate is retained in the porous structure, impurities in the combustible gas can be more reliably removed. Moreover, since molten carbonate is hold | maintained in a porous structure over a long period of time, the supply frequency of molten carbonate can be reduced.

According to a second aspect of the present invention, in the fuel gas purification device described in the first aspect, a plurality of the porous structures are disposed in the gas purification container, and the adjacent porous structures are disposed between the porous structures. to, in the fuel gas purification apparatus characterized by reaction agent formed from said functional material is retained.

  In the second aspect, more molten carbonate can be held by the plurality of porous structures and the reactants held by the porous structures. Therefore, impurities can be more reliably removed from the combustible gas.

  A third aspect of the present invention is the fuel gas purification apparatus according to the first or second aspect, wherein the porous body is formed of the functional material. is there.

  In the third aspect, the functionality can be exhibited also on the porous body side.

According to a fourth aspect of the present invention, in the fuel gas purification apparatus according to any one of the first to third aspects, the cell is an open pore.

In the fourth aspect, a communication hole in which a plurality of cells as open pores communicate with each other is formed in the porous structure, and fluid can come into contact with particles through the communication hole.

According to a fifth aspect of the present invention, in the fuel gas purification device according to any one of the first to third aspects, the cell is opened in communication with other closed pores because a part of the closed pores are cracked. The fuel gas purification apparatus is characterized in that it has pores.

In the fifth aspect, the porous structure is provided with a plurality of cells that are closed pores. The porous structure is compressed, thermally distorted, or chemically reacts, so that some of the closed pores are cracked, and when the other closed pores communicate with each other, a communication hole is formed in which each cell communicates. Is done. The fluid can come into contact with the particles through the communication hole. For example, it is possible to prevent the particles from coming into contact with outside air until the porous structure is transported to the site where it is actually used. And it becomes possible for the particles to come into contact with the fluid only after compression or the like at the site. Thereby, it is possible to prevent the function of the particles from being chemically reacted before being transported to the site.

According to a sixth aspect of the present invention, there is provided the fuel gas purification apparatus according to any one of the first to fifth aspects, and power generation means for generating electric power using the fuel gas from the fuel gas purification apparatus. The power generation system is characterized by

In the sixth aspect, power can be generated using the fuel gas purified by the fuel gas purification device.

According to a seventh aspect of the present invention, there is provided the fuel gas purification device according to any one of the first to fifth aspects and a pyrolysis gas obtained by pyrolyzing biomass to the fuel gas purification device. The carbonizer, the liquid fuel synthesizer for synthesizing the liquid fuel from the fuel gas from the fuel gas refining device, and the carbonizer so that the ratio of the moisture of the fuel gas supplied to the liquid fuel synthesizer can be adjusted. Alternatively, the fuel synthesizing system includes a water supply means for supplying water into the gas purification vessel.

In the seventh aspect, the ratio of the fuel gas carbon monoxide to hydrogen can be adjusted to a ratio suitable for the liquid fuel to be synthesized by adjusting the water supply means. Thereby, a desired liquid fuel can be manufactured.

  ADVANTAGE OF THE INVENTION According to this invention, the fuel gas refiner | purifier which can refine | purify combustible gas with high purity is provided. Furthermore, a power generation system having the fuel gas purification device and a fuel synthesis system are provided.

1 is a schematic configuration diagram of a power generation system according to Embodiment 1. FIG. 1 is a schematic configuration diagram of a fuel gas purification device according to Embodiment 1. FIG. 1 is a cross-sectional view illustrating a schematic configuration of a porous structure according to Embodiment 1. FIG. It is sectional drawing to which a part of FIG. 3 was expanded. 3 is a schematic configuration diagram of a fuel gas purification apparatus according to Embodiment 2. FIG. 6 is a cross-sectional view showing a schematic configuration of a porous structure according to Embodiment 3. FIG. It is sectional drawing which shows the manufacturing method of a porous structure. It is sectional drawing which shows the manufacturing method of a porous structure.

<Embodiment 1>
Hereinafter, the best mode for carrying out the present invention will be described. The description of the present embodiment is an exemplification, and the present invention is not limited to the following description.

  FIG. 1 is a schematic configuration diagram of a power generation system including a fuel gas purification device according to the first embodiment. As shown in the figure, a power generation system according to Embodiment 1 includes a carbonizer 1 that pyrolyzes biomass, a furnace 2 that burns carbides, and a fuel gas purification device 10 that purifies pyrolysis gas that is an example of combustible gas. And an introduction pipe 5 for introducing pyrolysis gas from the carbonizer 1 into the fuel gas purification apparatus 10, a carbide introduction pipe 7 for introducing carbide from the carbonizer 1 into the furnace 2, and fuel purified by the fuel gas purification apparatus 10. A fuel gas supply pipe 6 that supplies gas to the power generation means 20 and a power generation means 20 that generates power using the fuel gas as fuel are provided.

  The carbonizer 1 is supplied with woody biomass, waste biomass such as municipal waste, and mixed biomass thereof. The carbonizer 1 steams and burns biomass and pyrolyzes it to generate pyrolysis gas and carbide. Pyrolysis gas is composed of volatile components in biomass, and is mainly composed of carbon monoxide, hydrogen, water, hydrocarbons, tar, and the like. On the other hand, the carbide is a so-called char such as carbon or charcoal.

  The furnace 2 includes a lower gasification / combustion unit 2a and an upper container arrangement unit 2b. Carbide is supplied to the gasification / combustion unit 2 a from the carbonizer 1 through the carbide introduction pipe 7. Air or oxygen is separately introduced into the gasification / combustion unit 2a, and the carbide is combusted. As a result, high-temperature gas is generated in the gasification / combustion section 2a, and the high-temperature gas is guided to the upper container arrangement section 2b. Note that ash having a relatively low melting point in the burned carbide is discharged as molten slag from the bottom of the furnace 2.

  A gas purification container 11 constituting the fuel gas purification apparatus 10 is disposed in the container arrangement portion 2 b of the furnace 2. The fuel gas purification apparatus 10 purifies pyrolysis gas into fuel gas. That is, the gas purification vessel 11 is supplied with the pyrolysis gas generated in the carbonizer 1 through the introduction pipe 5, purifies the pyrolysis gas into fuel gas, and supplies the fuel gas to the power generation means 20 outside the furnace 2. Supply.

  The power generation means 20 is composed of, for example, a molten carbonate fuel cell (MCFC) provided with a fuel electrode to which fuel gas from the fuel gas supply pipe 6 is sent. MCFC is generally one that is highly efficient and can use carbon monoxide as a fuel among fuel cells.

  The power generation means 20 is not particularly limited as long as it generates power using the fuel gas from the fuel gas supply pipe 6. For example, the power generation means 20 may be composed of a gas engine that is operated by fuel gas from the fuel gas supply pipe 6 and a generator that is activated by the operation of the gas engine. In addition, the power generation means 20 includes a turbine combustor that combusts the fuel gas from the fuel gas supply pipe 6, and a gas turbine that drives the generator by obtaining power by expansion of the combustion gas from the turbine combustor. It may be comprised from these.

  The power generation means 20 and the carbonizer 1 are configured such that waste heat generated in the power generation means 20 becomes a heat source for the carbonizer 1 that heats biomass via a heat exchanger (not shown) or the like. ing. Thereby, the energy efficiency of the whole power generation system can be improved. Further, the furnace 2 and the carbonizer 1 are configured such that the waste heat generated in the furnace 2 becomes a heat source for the carbonizer 1 that heats the biomass via a heat exchanger (not shown) or the like. . Thereby, the energy efficiency of the whole power generation system can be further improved.

  The fuel gas purification apparatus 10 according to the present embodiment will be described in detail. FIG. 2 is a schematic configuration diagram of the fuel gas purification apparatus according to the first embodiment.

  As shown in the figure, the fuel gas purification apparatus 10 includes a gas purification container 11, a porous structure 30 disposed inside the gas purification container 11, and a carbonate supply means for supplying carbonate to the porous structure 30. 13.

  The gas purification container 11 is provided with a porous structure 30 so that a pyrolysis gas flows in the center thereof. More specifically, the introduction pipe 5 is disposed below the gas purification container 11, that is, below the porous structure 30, and above the gas purification container 11, that is, above the porous structure 30, A fuel gas supply pipe 6 is provided. In the gas purification container 11 having such a configuration, the pyrolysis gas introduced into the lower part of the gas purification container 11 flows through the porous structure 30 and is purified, and then discharged to the outside through the fuel gas supply pipe 6. It has become. In the present embodiment, the gas purification vessel 11 stores the molten carbonate 4 in the lower part thereof, and the pyrolysis gas is introduced into the molten carbonate 4, so that the pyrolysis gas is After the molten carbonate 4 is circulated, the porous structure 30 is circulated.

  Further, the gas purification vessel 11 is provided with carbonate supply means 13 for supplying the molten carbonate 17 to the porous structure 30. Specifically, the carbonate supply means 13 includes a carbonate container 14 that stores the carbonate in a molten state, a pump 15 that pumps the molten carbonate (molten carbonate 17) to the gas purification container 11, The nozzle 16 is configured to spray the molten carbonate 17 onto the porous structure 30. In the present embodiment, the carbonate supply unit 13 supplies the molten carbonate to the porous structure 30, but solid carbonate may be supplied to the porous structure 30. In this case, the solid carbonate is made into molten carbonate on the porous structure 30 by setting the temperature in the gas purification vessel 11 to be equal to or higher than the melting point of the carbonate.

The molten carbonate 17, lithium carbonate _(Li 2 _CO 3), sodium carbonate _(Na 2 _CO 3), the various alkali metal carbonate such as potassium carbonate _(K 2 CO _3), using those alone or mixed be able to. In addition to the alkali metal carbonates, carbonates such as magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and cerium (Ce) can be used as the molten carbonate. .

  The porous structure 30 will be described in detail with reference to FIGS. 3 and 4. As shown in the figure, the porous structure 30 according to this embodiment includes a porous body 31 and particles 33 held in the cells 32 thereof. The porous structure 30 is formed in a flat plate shape so as to contact the inner surface of the gas purification container 11. Of course, the porous structure 30 is not limited to such a shape, and may have an arbitrary shape. Moreover, it does not need to contact the inner surface of the gas purification container 11.

  The particles 33 are particles formed from a functional material. The shape of the particle 33 is not particularly limited, and details will be described later, but the particle 33 is held inside the cell 32 (may be fixed to the inner surface of the cell 32), and the size is from the inside of the cell 32 to the outside. So that it is not discharged.

  The functional material is at least one selected from the group consisting of metal oxides, metals and inorganics. These are appropriately selected according to the impurities to be removed from the pyrolysis gas. In the present embodiment, the particles 33 are formed of a material that acts as a catalyst in order to remove impurities in the pyrolysis gas using the molten carbonate 17.

  Examples of metals include nickel (Ni), copper (Cu), iron (Fe), vanadium (V), tungsten (W), titanium (Ti), cobalt (Co), ruthenium (Ru), palladium (Pd) , Zirconium (Zr), platinum (Pt), gold (Au), and the like. An alloy consists of two or more of these metals.

  The metal oxide is a compound oxide in which the above metals are oxidized or a composite oxide in which two or more of these metals are oxidized. Other metal oxides include single oxides such as alumina, zirconia, lithium aluminate, beta alumina, magnesium oxide, nickel oxide, calcium oxide or combinations comprising at least one of the foregoing. it can. Moreover, carbon can be mentioned as an inorganic substance.

  The porous body 31 refers to a structure having innumerable minute cells 32 (pores) inside, and further connecting these cells 32 from one surface to the other surface to form a communication hole. As the material of the porous body 31, the above-described functional material can be used.

  3 and 4 show a spherical structure as an ideal cell 32 structure. In the plurality of cells 32, adjacent cells 32 are connected to each other. The insides of the adjacent cells 32 communicate with each other through a connection port 34 that is an opening in which the cells 32 are connected. That is, most cells 32 of the porous body 31 are open pores (open cells). When the cells 32 communicate with each other, a large number of communication holes serving as pyrolysis gas flow paths as shown by arrows in FIG. 4 are formed. Note that not all cells 32 need to be open cells. It may be a porous body 31 partially including cells (closed pores) not communicating with the outside.

  The cell 32 is a pore formed in the porous body 31, and has a space large enough to hold the particles 33 therein. However, the particles 33 do not have to be held inside all the cells 32 included in the porous body 31. Further, the porosity of the porous body 31 is not particularly limited, but it is preferable to set the porosity so that the amount of particles 33 capable of sufficiently exhibiting the function corresponding to the use of the porous structure 30 can be held. The porosity is the ratio of the volume of the space occupied by the cells 32 to the volume of the porous body 31.

  The cell 32 has one or more connection ports 34 connected to the adjacent cells 32. The opening diameter of the connection port 34 is smaller than the diameter of the particles 33 held inside the cell 32. In other words, the particles 33 held inside the cell 32 do not escape from the connection port 34 to the outside.

  However, the opening diameters of all the connection ports 34 included in the cell 32 need not be smaller than the particles 33. For example, a connection port 34 having an opening diameter larger than that of the particle 33 may be provided in a certain cell 32, and the particle 33 can move to the other cell 32 side through such a connection port 34. May be. Finally, in any of the cells 32, a connection port 34 having an opening diameter smaller than that of the particle 33 (or an opening appearing on the outer surface of the porous body 31 (hereinafter referred to as an external opening)) is provided. It is only necessary that the particles 33 do not move outside the cell 32 from the connection port 34 (or external opening).

  By holding the particles 33 inside the cells 32 having such connection ports 34 (or external openings), the particles 33 are prevented from coming out of the cells 32 of the porous body 31.

  The molten carbonate 17 is supplied to the porous structure 30 from the nozzle 16 described above. The molten carbonate 17 supplied to the porous structure 30 permeates the entire cell 32 of the porous body 31. The molten carbonate 17 is held on the inner surface of the cell 32 in the cell 32 without the particles 33. In addition, the surface tension is increased by holding the particles 33 in the cells 32, and the molten carbonate is well held in the gap between the inner surfaces of the cells 32 and the particles 33. That is, the ability of the porous structure 30 to hold the molten carbonate 17 is higher than that of the porous body 31 that does not hold the particles 33.

  Furthermore, as described above, the porous structure 30 is configured such that the particles 33 are held in the cells 32 and are not easily dropped. Thereby, even if the pyrolysis gas flows through the porous structure 30, the particles 33 are maintained, so that the molten carbonate 17 is not easily spilled off. For this reason, the porous structure 30 maintains the impurity removal function for a long time.

  Further, when the functional material is simply coated on the surface of the porous body 31, the coated functional material may be peeled off together with the pyrolysis gas. However, according to the present invention, since the particles 33 formed from the functional material are physically held by the porous body 31, the porous structure 30 that maintains the functionality for a long period of time is provided. The

  Furthermore, the porous structure 30 can form the porous body 31 and the particles 33 with different functional materials. According to this, two types of catalytic actions can be realized simultaneously in one porous structure 30. Furthermore, with such a configuration, in the porous structure 30 according to the present invention, one type of functional material occupies the entire surface of the porous body 31, and the other type of functional material includes all the surfaces of the particles 33. Can occupy. That is, the porous structure 30 can sufficiently secure the contact area of various functional materials as compared with the case where two types of functional materials are applied to the porous body 31 without using the particles 33.

  Here, the mechanism by which impurities are removed by the reaction between the molten carbonate 17 and the pyrolysis gas will be described. As shown in FIG. 2, the molten carbonate 17 is supplied from the nozzle 16 to the porous structure 30 and held in the cells 32 and the particles 33. In this state, pyrolysis gas is supplied from the lower surface side of the porous structure 30. The following reaction is performed in the process in which the pyrolysis gas flows in the cell 32 from below to above.

Examples of impurities contained in the pyrolysis gas include sulfur (S) content, halogen (F, Cl) content, and nitrogen (N). From these elements, hydrogen sulfide (H ₂ S) is used in a high-temperature reducing atmosphere. ), Hydrogen chloride (HCl), hydrogen fluoride (HF), ammonia (NH ₃ ), and the like.

H ₂ S produced in a reducing atmosphere is taken into molten carbonate 17 as S ²⁻ , and HCl and HF are taken into molten carbonate 17 as Cl ⁻ and F ⁻ as alkali metal sulfide (M ₂ S). The chlorine content is captured as alkali metal chloride (MCl) and the fluorine content is captured as alkali metal fluoride (MF). As a result, the pyrolysis gas has its impurities removed by the molten carbonate 17 in the porous structure 30 and is purified to a fuel gas mainly composed of carbon monoxide and hydrogen. In such a reaction, the particles 33 act as a catalyst. When removing such impurities in the pyrolysis gas with the molten carbonate 17, it is preferable to form the particles 33 with a metal oxide such as zirconia.

  In addition, although the particle | grains 33 were formed with the functional material and it was set as the catalyst, it is not limited to such an aspect. The porous body 31 may be formed of a functional material and act as a catalyst, or both the particles 33 and the porous body 31 may be formed of a functional material as a catalyst.

  As described above, in the fuel gas purification apparatus 10 according to the present invention, the state in which the molten carbonate 17 is held in the porous structure 30 is maintained, so that impurities in the pyrolysis gas are efficiently performed. be able to. Incidentally, in the porous structure 30 that does not include the particles 33, the molten carbonate 17 is spilled and reacted with a small amount of the molten carbonate 17, so that the efficiency of removing impurities is lower than that of the present invention. .

  Further, in the prior art, it was necessary to form the cells 32 finely in order to hold the molten carbonate in the porous body. However, in the present invention, since the molten carbonate 17 is held by the cells 32 and the particles 33, the cells 32 themselves do not need to be fine. Therefore, the flow path resistance of the porous structure 30 with respect to the pyrolysis gas flowing in the gas purification vessel 11 can be made smaller than before. Thereby, the fuel gas refiner | purifier 10 can refine | purify the pyrolysis gas of more flow rates efficiently.

  In addition, if the reaction between the pyrolysis gas and the molten carbonate 17 continues, the porous structure 30 accumulates sulfur alkali metal and the like, and the molten carbonate 17 decreases. However, in the fuel gas purification apparatus 10 of the present invention, the carbonate supply means 13 is provided, so that the state in which the carbonate is held in the porous structure 30 can be maintained. Pyrolysis gas can be continuously purified to fuel gas. Furthermore, the supply frequency of the molten carbonate 17 by the carbonate supply means 13 can be reduced. This is because the molten carbonate 17 is well retained in the porous structure 30 as described above.

  In addition, the fuel gas purification apparatus 10 has the following characteristics. The molten carbonate 4 is stored in the lower part of the gas purification container 11. The molten carbonate 4 may be stored in the gas purification container 11 in advance, or may be spilled off from the porous structure 30. A pyrolysis gas is introduced into the molten carbonate 4 from an introduction pipe 5. At this time, impurities from the pyrolysis gas are removed by reaction with the molten carbonate 4. This reaction is the same as the reaction between the molten carbonate 17 and the pyrolysis gas in the porous structure 30.

  Thus, prior to reacting the pyrolysis gas with the molten carbonate 17 in the porous structure 30, the pyrolysis gas is reacted with the molten carbonate 4 stored in the gas purification vessel 11, thereby causing the pyrolysis. Impurities are more reliably removed from the gas, and a high-purity pyrolysis gas is obtained.

  It should be noted that the ash content 50 (hereinafter collectively referred to as the ash content 50) contained in the pyrolysis gas introduced from the carbonizer 1 is a gas purification vessel 11 because the molten carbonate 4 is liquid. It is possible to collect dust inside. Furthermore, tar contained in the pyrolysis gas also reacts with the molten carbonate 4 and is decomposed. The ash 50 is discharged to the outside through a discharge pipe 18 provided at the lower part of the gas purification container 11.

  The gas purification vessel 11 is provided with a mist trap 19. The mist trap 19 is disposed between the porous structure 30 and the fuel gas supply pipe 6, and traps a low melting point molten salt contained in the fuel gas purified through the porous structure 30. To do. Examples of such a molten salt include sodium hydroxide, sodium chloride, and potassium chloride. The molten salt is removed from the fuel gas by the mist trap 19, and a fuel gas purified to a higher purity is obtained.

  Although not particularly illustrated, the fuel gas purification device 10 may be provided with sodium hydroxide supply means (hydroxide supply means) for supplying sodium hydroxide (hydroxide) to the molten carbonate 4. When sodium hydroxide is supplied to the molten carbonate 4, the carbon dioxide in the molten carbonate 4 reacts with sodium hydroxide to produce sodium carbonate (carbonate).

  Incidentally, if the reaction between the molten carbonate 4 and the pyrolysis gas is continued without supplying sodium hydroxide, sulfur alkali metal or the like is accumulated in the gas purification vessel 11 and the molten carbonate 4 is reduced. It is necessary to replace the molten carbonate 4 in the container 11 as appropriate. For example, it is necessary to discharge the molten carbonate 4 and sulfur alkali metal in the gas purification container 11 to the outside through the discharge pipe 18 and supply new carbonate to the gas purification container 11. However, in the fuel gas purification apparatus 10 of the present invention, the carbonate is supplied to the gas purification vessel 11 while the fuel gas is purified by the molten carbonate 4 by appropriately supplying sodium hydroxide to the molten carbonate 4. The same effect can be obtained. Furthermore, since carbon dioxide contained in the molten carbonate 4 or the fuel gas (pyrolysis gas) is absorbed by sodium hydroxide and becomes sodium carbonate, the amount of carbon dioxide emitted can be reduced.

  Further, when the molten carbonate 4 in the gas purification vessel 11 is replaced, it is not limited to the case where the carbonate is supplied indirectly by supplying hydroxide to the molten carbonate 4 as described above. May be supplied into the gas purification vessel 11 to form the molten carbonate 4. The carbonate referred to here may contain water or baking soda.

  The hydroxide supply means is not limited to one supplying sodium hydroxide, and lithium hydroxide, magnesium hydroxide, potassium hydroxide, calcium hydroxide, strontium hydroxide, barium hydroxide, or cerium hydroxide is used. It may be supplied. In short, the hydroxide supply means is configured to supply a hydroxide capable of reacting with carbon dioxide in the molten carbonate 4 to form a carbonate to the molten carbonate 4 in the gas purification vessel 11. That's fine.

  In the power generation system including the fuel gas purification device 10 having the above-described configuration, pyrolysis gas and carbide are generated from biomass by the carbonizer 1, and the carbide melts the carbonate in the fuel gas purification device 10, or The molten carbonates 4 and 17 are burned to maintain a molten state. On the other hand, the pyrolysis gas is freed of impurities by the molten carbonate 4 and purified by the molten carbonate 17 of the porous structure 30 to become a fuel gas, and the power generation means 20 uses this highly purified fuel gas. Can generate electricity.

  Since the pyrolysis gas is purified by the molten carbonate 17 held in the porous structure 30 and the molten carbonate 4 stored in the gas purification vessel 11 in this way, more pyrolysis gas is used. It can be reacted with the molten carbonate 17, and the high purity fuel gas can be purified by sufficiently removing impurities from the pyrolysis gas.

  In addition, since the pyrolysis gas is purified in the gas purification vessel 11 disposed in the furnace 2, there is no need to provide an apparatus for purifying the fuel gas outside the furnace 2. Thereby, space saving of a power generation system can be achieved. In addition, since an apparatus having a complicated configuration as in the conventional gas purification apparatus is not required, the operability of the facility can be improved, and furthermore, the cost associated with the power generation system is reduced by the necessity of such an apparatus. it can.

  In the present embodiment, the gas purification container 11 is disposed in the furnace 2, but it is not necessarily disposed in the furnace 2. For example, the gas purification container 11 is disposed entirely or partially outside the furnace 2, and the thermal energy of carbides burned in the furnace 2 is disposed outside the furnace 2 via a heat exchanger or the like. 11 may be supplied. Even in this case, high-calorie fuel gas is refined and electric power can be generated using this fuel gas.

  Further, since the pyrolysis gas is refined into fuel gas inside the gas purification vessel 11 separated from the space inside the furnace 2, the fuel gas is not diluted with air or nitrogen used for the combustion of carbides. Absent. Further, as described above, impurities are removed from the fuel gas. From these things, the fuel gas whose calorie per unit volume is higher than before can be supplied from the fuel gas supply pipe 6. Thus, since the fuel gas purification apparatus 10 of the present invention purifies high-calorie fuel gas, in particular, a high-temperature fuel cell such as a molten carbonate fuel cell (MCFC) or a solid oxide fuel cell ( It is useful when applied to a power generation system using SOFC) as a power generation means.

  Further, the furnace 2 and the carbonizer 1 are configured such that the waste heat generated in the furnace 2 becomes a heat source for the carbonizer 1 that heats the biomass via a heat exchanger (not shown) or the like. . Thereby, the whole energy efficiency can be improved.

<Embodiment 2>
Although one porous structure 30 is provided in the fuel gas purification device 10 according to the first embodiment, the present invention is not limited to such a mode. FIG. 5 is a schematic configuration diagram of a fuel gas purification apparatus according to the second embodiment. In addition, the same code | symbol is attached | subjected to the same thing as Embodiment 1, and the overlapping description is abbreviate | omitted.

  As shown in the figure, three porous structures 30 are arranged in the gas purification container 11 at a predetermined interval. Each porous structure 30 is formed in a flat plate shape so as to be in contact with the inner surface of the gas purification container 11.

  A reactant 40 is held between the porous structures 30. The reactant 40 is made of a functional material. The specific functional material is the same as that used for the particles 33 of the porous structure 30. What is necessary is just to select suitably according to the impurity of the object removed from pyrolysis gas.

The shape of the reactant 40 is not particularly limited, but it is preferable that there is a void that does not hinder the flow of the pyrolysis gas supplied to the gas purification vessel 11. As a result, the flow path resistance of the reactant 40 with respect to the pyrolysis gas flowing in the gas purification vessel 11 becomes small, so the fuel gas purification device 10 efficiently purifies the pyrolysis gas with a larger flow rate. be able to.
In addition, the reactant 40 preferably has a shape that does not pass through the cell 32 and is retained on the porous structure 30. In the present embodiment, granular zirconia having a size that does not flow into the cell 32 of the porous structure 30 is used as the reactant 40.

  The molten carbonate 17 is supplied from the nozzle 16 to the plurality of porous structures 30 holding the reactant 40 in this way. As described in the first embodiment, the molten carbonate 17 is held in each porous structure 30 and the reactant 40. By providing a plurality of such porous structures 30, it is possible to more reliably prevent the molten carbonate 17 from spilling into the lower portion of the gas purification container 11.

  The pyrolysis gas supplied from the introduction pipe 5 (see FIG. 1) flows through each porous structure 30 and the reactant 40 held by them. In the porous structure 30, as described in the first embodiment, the pyrolysis gas is purified by the molten carbonate 17 and the particles 33 acting as a catalyst to become a fuel gas. Since the porous structure 30 is multi-staged, more impurities in the fuel gas can be removed.

  Further, the reactant 40 held between the porous structures 30 is zirconia that acts as a catalyst, like the particles 33. Therefore, impurities from the pyrolysis gas are also removed by the molten carbonate 17 and the reactant 40 held in the gap between the reactants 40. Then, the purified fuel gas is discharged out of the gas purification container 11 from the fuel gas supply pipe 6 (see FIG. 1).

  Thus, according to the fuel gas purification apparatus 10 according to the present embodiment, it is possible to hold more molten carbonate 17 by the plurality of porous structures 30 and the reactants 40 held thereby. Thus, the pyrolysis gas can be purified more reliably.

  When a plurality of porous structures 30 are used, it is not necessary to hold the reactant 40. That is, it is only necessary to install a plurality of porous structures 30 in the gas purification container 11.

<Embodiment 3>
The porous structure 30 according to the first embodiment and the second embodiment is configured such that the cell 32 communicates with the outside, but is not necessarily limited to such a mode. FIG. 6 is an enlarged cross-sectional view of a schematic configuration of a porous structure according to this embodiment and a part thereof. In addition, the same code | symbol is attached | subjected to the same thing as Embodiment 1, and the overlapping description is abbreviate | omitted.

  As shown in FIG. 6A, the porous structure 30 according to this embodiment includes a porous body 31 and particles 33 held in the cell 32 thereof.

  The porous body 31 has innumerable minute cells 32 (pores) inside, and these cells 32 are formed as closed pores (closed cells). As the material of the porous body 31, the above-described functional material can be used. However, not all cells 32 need to be closed pores. As in the first embodiment, the porous body 31 may include some open pores.

  FIG. 6A shows a spherical structure as an ideal cell 32 structure. The plurality of cells 32 are not connected to other adjacent cells 32.

  The cell 32 is a pore formed in the porous body 31, and has a space large enough to hold the particles 33 therein. That is, the particles 33 are confined in the space inside the cell 32.

  In such a porous structure 30, a part of the cell 32 is broken and communicates with another cell 32. For example, a part of the cell 32 is broken due to physical compression, thermal strain or chemical reaction, and communicates with the other cells 32. By such an action such as compression, most of the cells 32 of the porous body 31 become open pores, and the cells 32 communicate with each other, for example, a communication hole that becomes a fluid flow path as indicated by an arrow in FIG. Are formed in large numbers.

  The porous structure 30 formed in this way has the same effect as that of the first embodiment. For example, since the opening diameter of the connection port 34 is smaller than the diameter of the particle 33 held inside the cell 32 as in the first embodiment, the particles 33 held inside the cell 32 are connected to each other. The mouth 34 is prevented from coming out to the outside. Further, the state in which the molten carbonate is held by the cells 32 and the particles 33 can be maintained for a long time.

  In the porous structure 30 of the present embodiment, the particles 33 are initially held in the cells 32 as closed pores, and the fluid contacts the particles 33 in the cells 32 by an action such as compression of the porous structure 30. A communication hole that can be formed is formed. By adopting such a structure, it is possible to prevent the particles 33 from being exposed to the outside air until the porous structure 30 is transported to the site where it is actually used. The particles 33 can contact the fluid only when the cells 32 communicate with each other at the site. Thereby, it can prevent that the particle | grains 33 carry out a chemical reaction before conveying to a spot, and the function will deteriorate.

  The porous structure 30 according to Embodiment 3 can be manufactured, for example, as follows. First, a slurry in which a powdery functional material forming the porous body 31 is slurried is prepared, and particles 33 are mixed into the slurry. The porous structure 30 can be manufactured by heating and sintering while injecting bubbles into the slurry (bubbling).

As another manufacturing method, CaCO ₃ , MgCO ₃ or the like is used as a foaming agent, and these are coated on the particles 33. Then, the coated particles 33 are mixed with the molten metal. Thereafter, the temperature is raised to a foaming temperature at which the foaming agent foams and then rapidly cooled, whereby a closed cell is formed in the solid metal, and a porous structure in which the particles 33 are held in the closed cell is obtained.

  According to the method for manufacturing the porous structure 30 described above, it is possible to manufacture the porous structure 30 that can surely prevent the particles having the functionality held in the cells from falling off by a simple method. .

<Method for producing porous structure>
A method for manufacturing the porous structure 30 will be described. FIG. 7 is a cross-sectional view showing a method for manufacturing a porous structure according to the present embodiment.

  First, as shown in FIG. 7A, the periphery of the particles 33 is covered with a spacer material 56. The spacer material 56 is preferably melted by heating, and for example, an alkali metal compound is preferable. Examples of the alkali metal compound include sodium chloride, potassium chloride, sodium carbonate, potassium carbonate and the like.

  Next, as shown in FIG. 7B, the powdery functional material forming the porous body 31 and the particles 33 covered with the spacer material 56 are mixed and molded into a predetermined shape. For example, the particles 33 and the metal powder are mixed at a ratio such that a desired porosity is obtained, and formed into a flat plate shape.

  And as shown in FIG.7 (c), the shape | molded mixture is sintered. The spacer material 56 is melted by heating by this sintering, and is removed by washing with water. Thereby, the region where the spacer material 56 originally existed becomes the cell 32, and the porous structure 30 in which the particles 33 are held inside the cell 32 is formed. A portion where the adjacent spacer members 56 are in contact with each other serves as a connection port 34 between the cells 32.

  A manufacturing method of the porous structure 30 different from the manufacturing method described above will be described. FIG. 8 is a cross-sectional view showing a method for manufacturing a porous structure according to the present embodiment.

  First, as shown in FIG. 8A, a template material 57 in which a large number of cells 32 are defined is prepared. Particles 33 are mixed in a portion (partition wall) that defines the cell 32 of the template material 57. The template material 57 is preferably porous and melted by heating, and examples thereof include a material in which polyurethane is formed in a porous shape (urethane foam). Specifically, it is formed by mixing the particles 33 together with the foaming agent in the polyurethane raw material and foaming.

  Next, as shown in FIG. 8B, a template material 57 is impregnated with a slurry 58 obtained by slurrying a powdery functional material forming the porous body 31. As a result, the slurry 58 is held in the cell 32 of the template material 57.

  Then, as shown in FIG. 8C, the template material 57 impregnated with the slurry 58 is dried and heated. Thereby, the template material 57 is melted and removed to form the porous structure 30. As shown in FIG. 8D, in the porous structure 30 according to this manufacturing method, the powdered functional material sintered in the cell 32 portion of the template material 57 is located, and the gap is A cell 32 is formed, and the particles 33 are held in the cell 32. In this case, the portion where the template material 57 (partition wall) was originally located becomes a gap and becomes the connection port 34 between the cells 32.

  According to the method for manufacturing the porous structure 30 described above, it is possible to manufacture the porous structure 30 that can surely prevent the particles having the functionality held in the cells from falling off by a simple method. .

<Other embodiments>
In the first embodiment, the power generation system configured to supply the fuel gas produced by the fuel gas purification apparatus 10 to the power generation means 20 has been described. However, the fuel gas purification apparatus 10 synthesizes liquid fuel using the fuel gas as a raw material. It may be applied to a fuel synthesis system.

  Specifically, the fuel synthesis system includes a fuel gas purification device 10 and a liquid fuel synthesis device to which fuel gas purified by the fuel gas purification device 10 is supplied.

  The liquid fuel synthesizing apparatus is an apparatus that synthesizes a hydrocarbon liquid fuel such as methanol, dimethyl ether, or light oil from a fuel gas. This liquid fuel is generally known to be obtained by synthesizing a gas mainly composed of hydrogen and carbon monoxide at a temperature and pressure suitable for the reaction in the presence of a catalyst.

  The fuel synthesizing system may be provided with water supply means for supplying water into the carbonizer 1. By adjusting the amount of water supplied into the carbonizer 1, the ratio of the water content of the fuel gas supplied from the fuel gas supply pipe 6 to the liquid fuel synthesizing apparatus can be adjusted. By adjusting the moisture ratio in this way, the ratio of carbon monoxide and hydrogen constituting the fuel gas can be set to a desired ratio.

  Which type of liquid fuel to synthesize is determined by the ratio of carbon monoxide and hydrogen as raw materials. Therefore, when synthesizing a specific liquid fuel, the water supply means may be adjusted so that the ratio of carbon monoxide to hydrogen in the fuel gas is a ratio suitable for the liquid fuel. As described above, the fuel synthesizing system according to the present embodiment has the flexibility to produce a desired type of liquid fuel.

  The water supply means is not limited to supplying water into the carbonizer 1, and may be, for example, in the gas purification container 11 or may supply water to the introduction pipe 5 or the fuel gas supply pipe 6. Good. In short, the water supply means may be configured so that water can be added to the fuel gas (pyrolysis gas) before the fuel gas is supplied to the liquid fuel synthesizing apparatus.

  In Embodiments 1 to 3, the biomass-derived pyrolysis gas is the target of gas purification. However, the present invention is not limited to this, and the present invention can be widely applied to all combustible gases including combustible components. Examples of such combustible gas include coal gasification gas generated by gasification of coal in a gas furnace, digestion gas generated by decomposition of sludge by microorganisms, boil-off gas generated by evaporation of LNG and LPG, and the like. It is done.

  It can be used effectively in the industrial field in which equipment that generates electricity by burning a combustible gas such as biomass or equipment that is used as a raw material for liquid fuel is used, manufactured, and sold.

DESCRIPTION OF SYMBOLS 1 Carbonizer 2 Furnace 2a Gasification / combustion part 2b Container arrangement | positioning part 4,17 Molten carbonate 5 Introduction pipe 6 Fuel gas supply pipe 7 Carbide introduction pipe 10 Fuel gas refiner 11 Gas purification container 13 Carbonate supply means 14 Carbonate Container 15 Pump 16 Nozzle 18 Discharge pipe 19 Mist trap 20 Power generation means 30 Porous structure 31 Porous body 32 Cell 33 Particle 34 Connection port 40 Reagent 56 Spacer material 57 Template material 58 Slurry

Claims (7)

A gas purification container into which a flammable gas is introduced;
A porous structure provided in the gas purification container so that the combustible gas flows;
Carbonate supply means for supplying carbonate to the porous structure,
The gas purification container is configured to discharge a fuel gas, which is purified by a reaction with the carbonate, from a combustible gas that has circulated through the porous structure,
The porous structure includes a porous body that partitions a plurality of cells, and particles formed of a functional material, and the particles are held inside the cells having an opening diameter smaller than the diameter of the particles. ,
The fuel gas purifier according to claim 1, wherein the functional material is at least one selected from the group consisting of metal oxide, metal, alloy and carbon . The fuel gas purification apparatus according to claim 1, wherein
A plurality of the porous structures are disposed in the gas purification container,
A fuel gas purification apparatus, wherein a reactant formed from the functional material is held between the adjacent porous structures. In the fuel gas purification device according to claim 1 or 2,
The said porous body is formed from the said functional material. The fuel gas refiner | purifier characterized by the above-mentioned. In the fuel gas purification apparatus as described in any one of Claims 1-3 ,
The fuel gas refining device, wherein the cell is an open pore. In the fuel gas purification apparatus as described in any one of Claims 1-3 ,
The cell is a fuel gas refining device, wherein a part of the closed pores is broken and communicated with other closed pores to become open pores. A fuel gas purification device according to any one of claims 1 to 5 ,
A power generation system comprising: power generation means for generating power using the fuel gas from the fuel gas purification device. A fuel gas purification device according to any one of claims 1 to 5 ,
A carbonizer for supplying a pyrolysis gas obtained by pyrolyzing biomass to the fuel gas purification device;
A liquid fuel synthesizing device for synthesizing liquid fuel from the fuel gas from the fuel gas purification device;
A fuel synthesizing system comprising water supplying means for supplying water into the carbonizer or the gas refining vessel so as to adjust a moisture ratio of fuel gas supplied to the liquid fuel synthesizing apparatus. .

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