JP5601659B2 - Dry gas refining equipment and coal gasification combined power generation equipment - Google Patents

Description

  The present invention relates to a dry gas purification facility and a coal gasification combined power generation facility.

  Coal exists in a large area of the world, has a large recoverable reserve, and has a stable price, so it has a high supply stability and a low price per calorific value. As one method of thermal power generation using coal as a fuel, an integrated coal gasfication combined cycle (IGCC) is known. In coal gasification combined cycle power generation, electric power is obtained by driving a gas turbine using coal gasification gas as fuel, exhaust gas from the gas turbine is recovered to generate steam, and the generated steam drives the steam turbine to generate electric power. (See, for example, Patent Document 1).

  The coal gasification gas generated in the coal gasifier contains impurities such as sulfur compounds (sulfides), impurities that affect the following equipment, and trace components. Impurities are removed to make fuel gas.

  As gas purification equipment, wet gas purification equipment in which a water washing tower, a COS converter, and the like are installed is widely used. The wet gas purification equipment is capable of precision removal of trace components in the coal gasification gas, and is an equipment that takes into account the influence on subsequent equipment such as a gas turbine. However, since the wet gas purification equipment has a large loss of latent heat due to evaporation and condensation of moisture, there is a limit to increasing the efficiency when it is used for coal gasification combined power generation.

  On the other hand, various dry-type gas refining facilities that suppress the rise and fall of temperature and pressure, mainly remove sulfides, and purify high-temperature coal gasification gas have been studied. By refine | purifying coal gasification gas by dry type, since coal gasification gas can be refine | purified with high temperature, the raise and lower of temperature and pressure can be suppressed, and fuel gas can be obtained.

  In dry gas purification equipment, fuel gas can be obtained while maintaining temperature and pressure (suppressing pressure loss), but impurities and trace components that affect subsequent equipment have not been reliably removed. Is the current situation. For this reason, it is necessary to establish the operation of a remover for various impurities in consideration of the maintenance of temperature and pressure and the influence on subsequent equipment, and the actual situation is that it has not been put into practical use. .

  In dry gas refining equipment that purifies coal gasification gas, considering the maintenance of temperature and pressure, and taking into consideration the effects on subsequent equipment are not limited to fuel gas purification for power generation equipment, but also fuel gas for chemical synthesis The same problem exists in purification.

JP 2005-171148 A

  The present invention has been made in view of the above situation, and provides a dry gas purification facility capable of purifying coal gasification gas in a dry manner in consideration of the influence on the rise and fall of temperature and pressure and the influence on subsequent equipment. With the goal.

  In addition, the present invention has been made in view of the above situation, and includes a dry gas purification facility capable of purifying coal gasification gas in a dry manner in consideration of the influence on the rise and fall of temperature and pressure and the influence on subsequent equipment. The purpose is to provide a combined coal gasification combined power generation facility.

Dry gas purification equipment of the present invention according to claim 1 for achieving the above object, a halide by a dry method to operate while maintaining the coal gasification gas produced in the coal gasification furnace 4 50 ° C. of temperature A halide removing device for removing slag and a coal gasification gas from which the halide has been removed by the halide removing device is introduced, and the sulfide is removed by a dry process in which the coal gasification gas is maintained at a temperature of 450 ° C. A desulfurization apparatus that removes sulfur, and a coal gasification gas from which sulfides have been removed by the desulfurization apparatus, and a dry process in which the coal gasification gas is maintained at a temperature of 400 ° C. An ammonia decomposing apparatus for decomposing, and a heat exchange in which the coal gasified gas whose ammonia component is decomposed by the ammonia decomposing apparatus is introduced and the temperature of the coal gasified gas is lowered to 180 ° C. A device, the heat exchanger 1 80 coal gasification gas is cooled to ° C. is introduced in a mercury removal apparatus for removing mercury by a dry method to operate while maintaining the coal gasification gas to a temperature of 1 80 ° C. The coal gasification gas from which mercury has been removed by the mercury removal device is introduced, and the coal gasification gas is maintained at a temperature of 180 ° C. to remove impurities contained in the coal gasification gas by physical filtration. The fuel gas from which impurities are removed by the physical filtration device is sent to the heat exchange device, the coal gasification gas is used as a heat medium, and the fuel gas is 4 characterized in that it is heated to 00 ° C. or et 4 50 ° C..

  In the present invention according to claim 1, the halide of the coal gasification gas generated in the coal gasification furnace is removed by a dry method using a halide removal device, and the sulfide of the coal gasification gas from which the halide has been removed is desulfurized. It is removed dry by the device.

  For this reason, it is possible to remove the halogen compounds and sulfides of the coal gasification gas while maintaining a high temperature state, taking into consideration the influence on the rise and fall of temperature and pressure, and the influence of corrosion caused by the halide on the subsequent equipment. Coal gasification gas can be refined dry.

Moreover, the ammonia component of coal gasification gas is decomposed | disassembled by a dry type with an ammonia decomposition apparatus, and the fuel gas which suppressed the ammonia component can be obtained. As a result, nitrogen oxides in the exhaust gas discharged from the subsequent equipment are also suppressed, and for example, it is possible to reduce the load of the flue gas denitration equipment of the subsequent equipment.
Further, mercury contained in the coal gasification gas can be removed by a dry method by the mercury removing device.
Further, at the most downstream portion, impurities including solid precipitates, fine particles, and powder can be removed from the coal gasification gas by physical filtration.

The mercury removing agent used in the mercury removing apparatus, it is preferable to use a copper-based absorbent to remove mercury by absorbing mercury mainly of copper. Further, as the mercury removing agent, it is preferable to use an impregnated activated carbon that removes mercury by supporting a chemically reactive component and adsorbing a salt generated by a chemical reaction with mercury.

  Because copper-based absorbents and impregnated activated carbon exhibit absorption performance at low temperatures, the temperature of the coal gasification gas introduced into the mercury removal equipment is controlled to a temperature suitable for the operation of the mercury removal agent by means of heat exchange. Is done. The heat exchange means raises the temperature of the fuel gas from the physical filtration device by the sensible heat of the coal gasification gas introduced into the mercury removal device, and the temperature of the coal gasification gas introduced into the mercury removal device. The temperature drop can be controlled to the operation temperature of the mercury removing agent.

  For this reason, even when sensible heat for controlling the temperature of the coal gasification gas introduced into the mercury removal apparatus is recovered to raise the temperature of the fuel gas, and a mercury removal agent with a low operating temperature is applied. In addition, it is possible to achieve both temperature control with respect to the operating temperature of the mercury removal apparatus and high temperature maintenance of the fuel gas with a minimum loss of heat energy.

Things as the physical filtration device, in accordance with the temperature of the coal gasification gas to be introduced, it is possible to apply the ceramic filter or a bag filter or the like.

The dry gas purification facility of the present invention according to claim 2 is the dry gas purification facility according to claim 1, wherein the halide removing device is made of an alkaline halide absorbent formed into a pellet and made of coal. The coal gasification gas is distributed along the gasification gas introduction direction, the coal gasification gas circulates the halide absorbent in a direction crossing the introduction direction, and the desulfurization device is a honeycomb-shaped zinc oxide-based desulfurization agent. Are packed in a plurality of reaction towers, the reaction towers in which the desulfurization treatment is performed, the desulfurization agent is reduced by a part of the coal gasification gas from which the halogen compound has been removed. The reaction tower, the reaction tower for performing a sulfur component release process from the reduced desulfurizing agent, are arranged in parallel, and the desulfurization process, the reduction process, and the release process are sequentially switched, and the release is performed. Wherein the sulfur component recovery means for recovering the released sulfur components in management are provided.

In the present invention according to claim 2 , an alkali-based, preferably sodium-based halide absorbent formed into pellets is used, and the coal gasification gas is converted into a halide in a direction crossing the coal gasification gas introduction direction. Since it distribute | circulates to an absorber, coal gasification gas can be distribute | circulated to a halide absorber by what is called a radial flow format. For this reason, in the state which suppressed the pressure loss of coal gasification gas to the minimum, coal gasification gas can be made to contact the wide area of a halide absorber, and a halide can be removed reliably.

In addition, in the desulfurization apparatus, at the same time as performing the desulfurization process, the reduction process and the release process, which are regeneration of the desulfurization agent, can be performed online, and the desulfurization agent can be reused, and the released sulfur component can be recovered. it can. Further, since the desulfurizing agent has a honeycomb shape, a large capacity gas processing capability can be obtained in a state where pressure loss is suppressed, and waste can be greatly reduced by reusing the desulfurizing agent. As the sulfur component recovery means, means for recovering as sulfur itself or means for recovering sulfur as gypsum by the lime / gypsum method can be applied.

In order to achieve the above object, a combined coal gasification combined cycle facility according to the present invention according to claim 3 is produced by a coal gasification furnace that generates coal gasification gas by a reaction of coal and an oxidant, and the coal gasification furnace. 3. A dry gas refining facility according to claim 1 or 2 , wherein said coal gasification gas is purified to obtain a fuel gas, combustion means for burning the fuel gas obtained by said dry gas refining facility, and said combustion A gas turbine that obtains power by expanding the combustion gas from the means, and a steam turbine that obtains power by expanding the steam obtained by recovering the heat of the exhaust gas of the gas turbine. And

In the present invention according to claim 3 , combined power generation is performed by a gas turbine and a steam turbine using fuel gas obtained by refining coal gasification gas in a dry gas purification facility as fuel for the gas turbine. In the coal gasification furnace, a part of the high-pressure air on the gas turbine side is used as an oxidizing agent, and in the steam turbine, the steam generated by the sensible heat of the coal gasification gas is used as a part of the output source.

  For this reason, it can be set as the coal gasification combined cycle power generation equipment provided with the dry-type gas purification equipment which can refine the coal gasification gas by the dry type in consideration of the influence on the rise and fall of temperature and pressure and the influence on the subsequent equipment. .

  The dry gas purification equipment of the present invention can refine coal gasification gas in a dry manner in consideration of the influence on the rise and fall of temperature and pressure and the influence on the subsequent equipment.

  Further, the coal gasification combined power generation facility of the present invention is a coal equipped with a dry gas purification facility capable of purifying coal gasification gas in a dry manner in consideration of the influence on the rise and fall of temperature and pressure and the influence on the subsequent equipment. It becomes possible to use a combined gasification power generation facility.

1 is an overall configuration diagram of a combined coal gasification combined cycle facility according to an embodiment of the present invention. It is a schematic system diagram of the dry gas purification equipment 4 according to the first reference example of the present invention. It is a schematic system diagram of the dry gas purification equipment 4 according to the second reference example of the present invention. It is a schematic system diagram of the dry gas purification equipment 4 according to the third reference example of the present invention. It is a general | schematic systematic diagram of the dry-type gas purification equipment 4 which concerns on the 4th reference example of this invention. It is a general | schematic systematic diagram of the dry-type gas purification equipment 4 which concerns on the 5th reference example of this invention. 1 is a schematic system diagram of a dry gas purification facility 4 according to an embodiment of the present invention. It is a specific block diagram of a dry gas purification facility.

  The coal gasification combined power generation facility will be described with reference to FIG.

  FIG. 1 shows a schematic system for explaining the overall configuration of a combined coal gasification combined power generation facility according to an embodiment of the present invention equipped with a dry gas purification facility.

  The combined coal gasification combined power generation facility 1 shown in the figure includes a coal gasification furnace 2, and a coal gasification gas g is generated in the coal gasification furnace 2 by a reaction between coal and an oxidizing agent (oxygen, air). The coal gasification gas g is dedusted by a dust removing means (not shown), adjusted to a predetermined temperature by the heat exchanger 3, impurities are removed by the dry gas refining equipment 4, and the fuel gas f is obtained.

  The fuel gas f is sent to the combustor 6 of the turbine equipment 5. That is, the turbine equipment 5 includes a compressor 16 and a gas turbine 7, and compressed air and fuel gas f compressed by the compressor 16 are sent to the combustor 6. In the combustor 6, the fuel gas f is combusted, and the combustion gas is sent to the gas turbine 7 and expanded to obtain power. The exhaust gas from the gas turbine 7 is heat recovered by the exhaust heat recovery boiler 8, and after nitrogen oxides are removed by the flue gas denitration device 9, the exhaust gas is discharged from the chimney 10 to the atmosphere.

  On the other hand, the compressor 16 and the gas turbine 7 and the steam turbine 11 are connected in a coaxial state, and the generator 12 is connected to the steam turbine 11. The exhaust heat recovery boiler 8 is supplied with condensate obtained by condensing the exhaust steam of the steam turbine 11 with a condenser (not shown), and the exhaust heat recovery boiler 8 generates steam by the exhaust gas of the gas turbine 7. The steam generated in the exhaust heat recovery boiler 8 is sent to the steam turbine 11 to obtain power.

  The generator 12 is driven by the power of the gas turbine 7 and the steam turbine 11 connected in series, and combined power generation by the gas turbine 7 and the steam turbine 11 is performed.

  In the coal gasification combined power generation facility 1 described above, the compressed air of the compressor 16 is extracted and supplied as the oxidant of the coal gasification furnace 2 (A). A part of the condensate sent to the exhaust heat recovery boiler 8 is supplied to the heat exchanger 3 (B), steam is generated by heat exchange with the coal gasification gas, and the generated steam is sent to the steam turbine 11. (C). For this reason, a part of the compressed air of the turbine equipment 5 is used as an oxidant, and the output of the steam turbine 11 can be obtained with the steam generated from the exhaust heat recovery boiler 8 and the heat exchanger 3.

  In the combined coal gasification combined power generation facility 1 having the above-described configuration, the coal gasification gas g is purified by the dry gas refining facility 4 by dry refining to obtain the fuel gas f.

  The dry gas purification equipment 4 will be described with reference to FIGS.

FIGS. 2 to 6 show schematic systems of the dry gas purification equipment 4 according to the first to fifth reference examples as references for the present invention, and FIG. 7 shows the dry gas purification equipment according to one embodiment of the present invention. 4 schematic systems are shown. The same members as those shown in FIG. 1, common members from the first reference example to the fifth reference example, and one embodiment are denoted by the same reference numerals. Further, although the configurations of the first reference example to the fifth reference example and one embodiment are different, they correspond to the dry gas purification equipment 4 shown in FIG. In the example, the dry gas purification equipment 4 is described.

A first reference example will be described with reference to FIG.

As shown in the figure, the dry gas refining equipment 4 of the first reference example is a halogen that removes halide from the coal gasification gas g produced in the coal gasification furnace 2 at about 450 ° C. (operating temperature above the dew point). Desulfurization that removes sulfide at a temperature of about 450 ° C. (operating temperature above the dew point) with the removal of halide 21 and the coal gasification gas g from which the halide has been removed by the halide removal device 21. A device 22 is provided. The sulfide is removed by the desulfurization device 22 to obtain the fuel gas f, and the fuel gas f in a high temperature state (for example, about 450 ° C.) is sent to the combustor 6 (see FIG. 1) of the turbine equipment 5.

In the halide removing device 21, sodium aluminate (NaAlO ₂ ), which is a sodium-based halide absorbent, is used as an alkali-based material in the form of pellets, and halides such as hydrogen chloride (HCl) and hydrogen fluoride ( HF) is removed simultaneously.

In the desulfurization apparatus 22, a zinc ferrite desulfurization agent, which is a zinc oxide-based desulfurization agent, is used after being formed into a honeycomb shape, and by bringing the coal gasification gas g into contact with the zinc ferrite desulfurization agent, sulfur sulfide (H ₂ S) or Carbonyl sulfide (COS) and the like are removed to a very low concentration. Since the zinc ferrite desulfurizing agent itself has the function of a hydrogenation catalyst, the performance can be exerted on organic sulfur compounds including carbonyl sulfide (COS).

In the first reference example , the halide of the coal gasification gas g generated in the coal gasification furnace 2 is removed by the dry method using the halide removal device 21, and the sulfide of the coal gasification gas g from which the halide has been removed is obtained. The fuel gas f in a high temperature state (for example, about 450 ° C.) can be obtained by being removed dry by the desulfurization device 22. For this reason, it becomes possible to refine | purify the coal gasification gas g by a dry type in consideration of the influence with respect to raising / lowering of a temperature or a pressure, and the influence of the halide and sulfide to a subsequent apparatus.

A second reference example will be described with reference to FIG.

The dry gas purification equipment 4 of the second reference example is configured to include an ammonia decomposition device 23 downstream of the desulfurization device 22 with respect to the first reference example . The gasification gas g from which the sulfide has been removed by the desulfurization device 22 is introduced into the ammonia decomposition device 23, which decomposes the ammonia component at about 400 ° C. (operating temperature above the dew point). Due to the exothermic reaction, the fuel gas f in a high temperature state (for example, about 500 ° C.) is obtained.

In the ammonia decomposing apparatus 23, the Ni / Al ₂ O ₃ catalyst is used in the form of pellets, and the ammonia component contained in the coal gasification gas g is decomposed into nitrogen (N ₂ ). For this reason, the fuel gas f which suppressed the ammonia component can be obtained, the nitrogen oxide in the exhaust gas of the gas turbine 7 (refer FIG. 1) is suppressed, and the load of the flue gas denitration apparatus 9 (refer FIG. 1) is reduced. It becomes possible to reduce.

A third reference example will be described with reference to FIG.

The dry gas purification equipment 4 of the third reference example is configured to include a high-temperature filter (for example, a ceramic filter) 24 as a physical filtration device downstream of the desulfurization device 22 (most downstream portion) with respect to the first reference example. Yes. The high-temperature filter 24 is introduced with the coal gasification gas g from which the sulfide has been removed by the desulfurization device 22, and the impurities including solid precipitates, fine particles, and powder contained in the coal gasification gas g are physically filtered. The fuel gas f in a high temperature state (for example, about 450 ° C.) is obtained. Therefore, the fuel gas f can be obtained by removing impurities from the coal gasification gas g by physical filtration at the most downstream portion.

A fourth reference example will be described with reference to FIG.

The dry gas purification equipment 4 of the fourth reference example is provided with an ammonia decomposition device 23 downstream of the desulfurization device 22 with respect to the first reference example, and a high-temperature filter (for example, a ceramic filter) downstream of the ammonia decomposition device 23 (most downstream part). ) 24. For this reason, the ammonia component of the coal gasification gas g is suppressed, and furthermore, a fuel gas f in a high temperature state (for example, about 500 ° C.) from which impurities are removed by physical filtration at the most downstream portion can be obtained.

A fifth reference example will be described with reference to FIG.

As shown in the figure, the dry gas refining facility 4 of the fifth reference example is a halogen that removes halide from the coal gasification gas g produced in the coal gasification furnace 2 at about 450 ° C. (operating temperature above the dew point). Desulfurization that removes sulfide at a temperature of about 450 ° C. (operating temperature above the dew point) with the removal of halide 21 and the coal gasification gas g from which the halide has been removed by the halide removal device 21. A device 22 is provided.

  A heat exchange device 25 is provided downstream of the desulfurization device 22, and the temperature of the coal gasification gas g from which the sulfide has been removed is lowered to, for example, about 180 ° C. by the heat exchange device 25. A mercury removing device 26 is provided downstream of the heat exchange device 25, and the mercury removing device 26 removes mercury contained in the coal gasification gas g at an operating temperature of about 180 ° C.

  A bag filter 27 as a physical filtration means is provided downstream (most downstream portion) of the mercury removing device 26, and solid precipitates, fine particles, and the like contained in the coal gasification gas g from which mercury has been removed by the mercury removing device 26. Impurities including powder are filtered by the bag filter 27. The coal gasified gas g is filtered into the fuel gas f by impurities being filtered by the bag filter 27, and is heated by the heat exchange device 25 by the sensible heat of the coal gasified gas g sent from the desulfurization device 22 to a high temperature (for example, about The fuel gas f is 400 ° C. to about 450 ° C.).

  In the mercury removal apparatus 26, a copper-based absorbent that absorbs mercury mainly using copper is used, and the mercury gas is absorbed and removed by bringing the coal gasification gas g into contact with the copper-based absorbent. Since the temperature suitable for the reaction of the copper-based absorbent is, for example, about 180 ° C., the high-temperature (about 450 ° C.) coal gasified gas g from which sulfide has been removed is heated to about 180 ° C. by the heat exchange device 25. The temperature is lowered.

  The cooling medium of the heat exchange device 25 is a low-temperature (about 180 ° C.) fuel gas f in which impurities are filtered by the bag filter 27 and the temperature is raised by the heat exchange device 25. The sensible heat of the coal gasification gas g at a high temperature (about 450 ° C.) can be used to raise the temperature of the fuel gas f at a low temperature (about 180 ° C.) to recover thermal energy in the system.

  For this reason, when the sensible heat for controlling the temperature of the coal gasification gas g introduced into the mercury removing device 26 is recovered to raise the temperature of the fuel gas f, and a copper-based absorbent having a low operating temperature is applied Even so, it is possible to achieve both temperature control with respect to the operating temperature of the mercury removing device 26 and high temperature maintenance of the fuel gas f with a minimum loss of heat energy.

Based on FIG. 7, the dry-type gas purification equipment 4 which concerns on one Example of this invention is demonstrated .

The dry gas purification facility according to one embodiment of the present invention is provided with an ammonia decomposition device 23 downstream of the desulfurization device 22 with respect to the facility described in the fifth reference example. The ammonia component of the gasification gas g is suppressed. Therefore, removal of halides and sulfides, suppression of ammonia components, removal of mercury and impurities can be performed dry, minimizing heat energy loss, removing various impurities dry, and high temperature The fuel gas f maintained at can be obtained.

Accordingly, the dry gas purification equipment 4 of the above-described embodiment includes the features of the first reference example to the fifth reference example, suppresses the loss of thermal energy, considers the influence on the rise and fall of temperature and pressure, It is possible to obtain the fuel gas f maintained at a high temperature by refining the coal gasification gas g in a dry manner in a state where the impurities are removed and the influence on the subsequent equipment is taken into consideration.

  In the dry gas purification facility 4 described above, the fuel gas f maintained at a high temperature obtained by refining the coal gasification gas g is supplied to the combustor 6 (see FIG. 1) of the turbine facility 5 (see FIG. 1). The fuel gas f to be supplied has been described as an example. However, the fuel gas f can be applied to other uses. For example, the fuel gas f can be applied as a fuel for a facility for performing fuel synthesis or as a fuel for a molten carbonate fuel cell. .

Based on FIG. 8, the specific structure of the dry-type gas purification equipment 4 which concerns on one Example of this invention is demonstrated.

FIG. 8 shows a system for explaining a specific configuration of the dry gas purification facility. The system configuration shown in FIG. 8 is a specific configuration of the dry gas purification equipment 4 of the embodiment shown in FIG. For this reason, the same members as those shown in FIG.

The halide removing device 21 into which the coal gasification gas g adjusted to a predetermined temperature by the heat exchanger 3 (see FIG. 1) is introduced is configured by arranging halide removers 31 and 32 in parallel. The introduction of the coal gasification gas g into the halide removers 31 and 32 is performed by switching to one of the switching means. The halide removers 31 and 32 are filled with sodium aluminate (NaAlO ₂ ) pellets, which are sodium halide absorbers, as alkalis, and the halide absorbents 33 formed into pellets are used to remove halides. The insides of the cylinders of the vessels 31 and 32 are filled along the introduction direction of the coal gasification gas g (up and down direction).

  Coal gasification gas g is introduced into the center of the inside of the cylinder from the upper part of the halide removers 31 and 32 downward, and the halide absorbent 33 disposed around the inside of the cylinder in a direction crossing the introduction direction. In contrast, coal gasification gas g circulates. The coal gasification gas g from which the halide has been removed through the halide absorbent 33 is sent to the desulfurization device 22 from the lower part of the halide removers 31 and 32.

Since sodium aluminate molded into pellets is used as the halide absorbent 33, hydrogen chloride and hydrogen fluoride in the coal gasification gas g react with sodium aluminate to cause harmless and low toxicity sodium chloride ( NaCl) and thiolite (Na ₅ Al ₃ F ₁₄ ) are removed. As a result, the halide in the coal gasification gas g is reduced to 1 ppm or less.

  In the halide removing device 21, the coal gasification gas g is circulated through the halide absorbent 33 in a direction crossing the introduction direction of the coal gasification gas g. The absorbent 33 can be distributed. For this reason, the coal gasification gas g can be brought into contact with a wide area of the halide absorbent 33 in a state where the pressure loss of the coal gasification gas g is suppressed to the minimum, and the halide can be removed without causing pressure loss. It can be removed reliably.

  In the halide removers 31 and 32, the coal gasification gas g normally circulates on either one side. On the other side where the coal gasification gas g is not circulated, a hopper (not shown) is used, and the used halide absorbent 33 is discharged from the lower part, and a new halide absorbent 33 is filled from the upper part. The By switching the flow of the coal gasification gas g to the halide removers 31, 32, the flow of the coal gasification gas g and the exchange of the halide absorbent 33 can be performed simultaneously, and the halide can be stopped without stopping the operation. It is possible to carry out the removal continuously.

  The coal gasification gas g from which the halide has been removed by the halide removing device 21 is sent to the desulfurization device 22.

  In the desulfurization apparatus 22, three reaction towers 35, 36, and 37 are arranged in parallel. In the reaction towers 35, 36, and 37, a catalyst block 38 in which a catalyst in which a zinc ferrite desulfurizing agent is formed into a honeycomb shape is assembled is provided. Each is filled with a plurality (four in the illustrated example). The introduction of the coal gasification gas g into the three reaction towers 35, 36, and 37 is performed by switching to any one by a switching means (not shown).

  That is, the three reaction towers 35, 36, and 37 are subjected to the reduction treatment of the zinc ferrite desulfurization agent by the reaction tower in which the desulfurization treatment is performed and a part of the coal gasification gas g from which the halogen compound has been removed. A reaction tower and a reaction tower in which a sulfur component is released from the reduced zinc ferrite desulfurization agent are arranged side by side. Then, the desulfurization process, the reduction process, and the release process are sequentially switched by a switching unit (not shown).

In the desulfurization treatment, the coal gasification gas g comes into contact with the zinc ferrite desulfurization agent (catalyst block 38), thereby removing sulfur sulfide (H ₂ S), carbonyl sulfide (COS), and the like. The zinc ferrite desulfurization agent exhibits a high-performance desulfurization function by synergism between zinc ferrite (ZnFe ₂ O ₄ ) iron and zinc. For example, the temperature of the coal gasification gas g is 450 ° C., the pressure is 0.98 MPa, and the sulfur content can be reduced to a low concentration of 1 ppm or less.

  In the three reaction towers 35, 36, and 37, for example, most of the coal gasification gas g from which the halide has been removed is sent to the reaction tower 35, and desulfurization processing is performed in the reaction tower 35. A part (small amount) of the coal gasification gas g is sent to the reaction tower 36, and reduction treatment is performed in the reaction tower 36. Further, the coal gasification gas g containing sulfur dioxide that has been subjected to the reduction treatment in the reaction tower 36 is supplied to the middle part of the reaction tower 37, and the sulfur treatment of the reaction tower 37 is performed. In the three reaction towers 35, 36, and 37, the gas flow state is sequentially switched every predetermined period, and the desulfurization treatment is performed in any of the reaction towers 35, 36, and 37.

  The released sulfur component is sent to the sulfur component recovery means 39 and recovered as gypsum by, for example, the lime / gypsum method. As the sulfur component recovery means 39, a means for recovering sulfur itself from the sulfur component can also be used.

  In the desulfurization apparatus 22 described above, the desulfurization process is performed, and simultaneously, the reduction process and the release process, which are regeneration of the zinc ferrite desulfurization agent, are performed online, and the zinc ferrite desulfurization agent is regenerated and reused in the process of continuous operation. Can do. As a result, the amount of waste discharged can be greatly reduced and the environmental load can be reduced. Further, since the zinc ferrite desulfurizing agent is formed into a honeycomb shape, a large volume of coal gasification gas g can be processed with a small pressure loss.

  Although a honeycomb-shaped catalyst is used as the desulfurizing agent, other forms of catalyst can be used depending on the scale of the apparatus and equipment and the flow rate of the coal gasification gas g.

  The coal gasification gas g from which the sulfur component has been removed by the desulfurization device 22 is sent to the ammonia decomposition device 23.

In the ammonia decomposition apparatus 23, reaction vessels 41 and 42 are arranged in parallel. The coal gasification gas g is introduced into the reaction vessels 41 and 42 by switching to one of the switching means. The reaction vessels 41 and 42 are filled with pellets of Ni / Al ₂ O ₃ catalyst, and the catalyst 43 formed into pellets is introduced around the inside of the cylinders of the reaction vessels 41 and 42 in the direction in which the coal gasification gas g is introduced. (Up and down direction) is filled.

  Coal gasification gas g is introduced from the upper part of reaction vessels 41 and 42 downward into the center of the inside of the cylinder, and coal gas is applied to catalyst 43 disposed around the inside of the cylinder in a direction crossing the introduction direction. Gasified gas g circulates. The coal gasification gas g in which the ammonia component has been decomposed into nitrogen through the catalyst 43 is sent to the heat exchange device 25 from the lower part of the reaction vessels 41 and 42.

  In the ammonia decomposing apparatus 23, the coal gasification gas g is circulated through the catalyst 43 in a direction crossing the direction of introduction of the coal gasification gas g, so that the coal gasification gas g is circulated through the catalyst 43 in a so-called radial flow format. Can do. Therefore, the coal gasification gas g can be brought into contact with a wide area of the catalyst 43 in a state where the pressure loss of the coal gasification gas g is suppressed to the minimum, and the ammonia component is reliably decomposed without accompanying the pressure loss. can do.

  In the reaction vessels 41 and 42, the coal gasification gas g normally circulates on either side. The catalyst 43 can be used repeatedly, but either side is arranged as a spare. If a problem occurs in the catalyst 43 on one side during operation, the circulation of the coal gasification gas g is switched to the spare catalyst 43 so that the continuous operation is continued. The desulfurization device 22 may be configured with a single reaction vessel 41.

  The coal gasification gas g in which the ammonia component has been decomposed into nitrogen is cooled by the heat exchange device 25 and sent to the mercury removal device 26.

  In the mercury removing device 26, the removal container 45 is filled with a copper-based absorbent 46 that mainly absorbs copper and absorbs mercury. For example, a coal gasification gas g of about 180 ° C. is introduced to absorb mercury. Since the coal gasification gas g of about 180 ° C. at which the water contained in the coal gasification gas g does not condense is introduced at the optimum operating temperature of the copper-based absorbent 46, the copper absorption capacity is secured to condense the moisture. Can be suppressed.

  The mercury removing device 26 is provided with mercury recovery means 47, which releases mercury absorbed by the copper-based absorbent 46 and restores mercury absorption performance. For example, mercury absorbed by a high-temperature gas is released, and the released mercury is absorbed by activated carbon at room temperature, so that a large amount of mercury can be absorbed and recovered with respect to a minimum amount of activated carbon.

  The coal gasification gas g from which mercury has been removed by the mercury removing device 26 is sent to the bag filter 27.

  In the bag filter 27, impurities including solid precipitates, fine particles, and powder contained in the coal gasification gas g from which mercury has been removed by the mercury removing device 26 are physically filtered. That is, in the bag filter 7, the dust including the powdered copper-based absorbent 46, the dust containing the material powdered on the upstream side, the tar content, the trace material, and various solid precipitated particles condensed at about 180 ° C. are the best. It is filtered and removed in the downstream part.

  The fuel gas f from which impurities are physically filtered by the bag filter 27 is heated from 400 ° C. to 450 ° C. by the sensible heat of the coal gasification gas g from which ammonia has been decomposed, and is heated to a high temperature. The fuel gas f is used. The high-temperature fuel gas f is supplied to the combustor 6 (see FIG. 1) of the turbine equipment 5 (see FIG. 1).

  In the dry gas refining equipment 4 shown in FIG. 8, the coal gasification gas g generated in the coal gasification furnace 2 is removed by the dry method using the halide removal device 21, and the coal gasification from which the halide has been removed is removed. The sulfide of the gas g is removed by the desulfurization device 22 in a dry manner. Thereafter, the ammonia component of the coal gasification gas g is decomposed in a dry manner by the ammonia decomposition device 23, mercury is removed by the mercury removal device 26, and impurities including solid precipitates, fine particles, and powder by the bag filter 27 at the most downstream portion. Are removed by physical filtration.

  For this reason, since various impurities of the coal gasification gas g can be removed while maintaining a high temperature state, impurities that cause corrosion of components of the gas turbine 7, cooling holes of the blades, and flow of fluid Impurities that cause blockages can be removed in a dry manner. Therefore, it is possible to obtain the high-temperature fuel gas f in a state in which the coal gasification gas g is purified by a dry method while the influence on the subsequent equipment is suppressed and no drainage is realized.

  In the halide removing device 21, the coal gasification gas g is circulated through the halide absorbent 33 in a radial flow format. In the desulfurization device 22, the coal gasification gas g is circulated through the honeycomb-shaped desulfurization agent, In the ammonia decomposing apparatus 23, the coal gasification gas g is circulated through the catalyst 43 in the radial flow format, so that the pressure loss of the coal gasification gas g can be greatly reduced, and the high-pressure fuel gas f is obtained. be able to.

  Furthermore, since the sensible heat of the coal gasification gas g obtained by decomposing the ammonia component in the ammonia decomposition device 23 is used as a heat source for raising the temperature of the fuel gas f by the heat exchange device 25, the heat energy is recovered in the system. Thus, the operating temperature in the mercury removing device 26 can be controlled to an optimum temperature at which water does not condense, and a high temperature fuel gas f can be obtained.

  Further, the halide removing device 21 and the ammonia decomposing device 23 can be replaced by extracting and filling the pellet-shaped halide absorbent 33 and the catalyst 43, so that the operability, maintainability and operability are improved. Can build high equipment.

  In addition, since the desulfurization unit 22 and the mercury removal unit 26 perform online regeneration of the catalyst and the copper-based absorbent and recover the sulfur component and mercury, the discharged waste can be reduced. Combined with the drainage facility, it is possible to greatly reduce the pollutants discharged to the environment and to make the facility simple and compact.

  In the combined coal gasification combined power generation facility 1 provided with the dry gas purification facility 4 described above, the fuel gas f, which is maintained in a high temperature and high pressure state by removing various impurities in a dry manner, is supplied to the turbine facility 5. For this reason, the efficiency of the entire power generation facility can be improved. For example, the power generation efficiency is about several percent compared to the power generation efficiency of about 45% obtained by a coal gasification combined power generation facility to which a wet gas purification facility is applied. For example, the power generation efficiency of about 48% can be achieved. In addition, the environmental load is reduced, and waste treatment facilities and wastewater treatment facilities are no longer required, making it possible to reduce the cost of construction facilities by making the facilities compact.

  The present invention can be used in the industrial fields of dry gas refining equipment and coal gasification combined power generation facilities.

DESCRIPTION OF SYMBOLS 1 Coal gasification combined cycle power generation equipment 2 Coal gasification furnace 3 Heat exchanger 4 Dry-type gas purification equipment 5 Turbine equipment 6 Combustor 7 Gas turbine 8 Waste heat recovery boiler 9 Flue gas denitrification device 10 Chimney 11 Steam turbine 12 Generator 16 Compression Machine 21 Halide removal device 22 Desulfurization device 23 Ammonia decomposition device 24 High temperature filter 25 Heat exchange device 26 Mercury removal device 27 Bag filter 31, 32 Halide removal device 33 Halide absorber 35, 36, 37 Reaction tower 38 Catalyst block 39 Sulfur component recovery means 41, 42 Reaction vessel 43 Catalyst 45 Removal vessel 46 Copper-based absorbent 47 Mercury recovery means

Claims (3)

A halide removal device for removing the halide by a dry method to operate while maintaining the coal gasification gas produced in the coal gasification furnace 4 50 ° C. of temperature,
A desulfurization apparatus for removing sulfides by a dry method in which a coal gasification gas from which halide has been removed by the halide removal apparatus is introduced, and the coal gasification gas is operated while being maintained at a temperature of 450 ° C .;
An ammonia decomposing apparatus for decomposing an ammonia component by a dry process using a dry process in which a coal gasification gas from which sulfides have been removed by the desulfurization apparatus is introduced and the coal gasification gas is maintained at a temperature of 400 ° C.
A heat exchange device for introducing a coal gasification gas in which the ammonia component has been decomposed by the ammonia decomposition device, and lowering the coal gasification gas to 180 ° C .;
The heat exchange device 1 80 coal gasification gas is cooled to ° C. is introduced in a mercury removal apparatus for removing mercury by a dry method to operate while maintaining the coal gasification gas to a temperature of 1 80 ° C.,
The coal gasification gas from which mercury has been removed by the mercury removal device is introduced, the coal gasification gas is maintained at a temperature of 180 ° C., and impurities contained in the coal gasification gas are removed by physical filtration. A physical filtration device for obtaining fuel gas,
The fuel gas from which impurities have been removed by physical filtration device is sent to the heat exchanger, said fuel gas coal gasification gas is a heat transfer medium is heated to 4 00 ° C. or et 4 50 ° C. Dry gas purification equipment characterized by The dry gas purification equipment according to claim 1,
The halide removing device is:
Alkaline halide absorbent formed into pellets is arranged along the introduction direction of the coal gasification gas, and the coal gasification gas flows through the halide absorbent in a direction crossing the introduction direction,
The desulfurization apparatus includes:
A plurality of reaction towers are filled with a honeycomb-shaped zinc oxide-based desulfurization agent,
The plurality of reaction towers are subjected to reduction treatment, the reaction tower in which desulfurization treatment is performed, the reaction tower in which reduction treatment of the desulfurization agent is performed by a part of the coal gasification gas from which the halogen compound has been removed. The reaction tower in which the sulfur component is released from the desulfurization agent is installed in parallel, and the desulfurization treatment, the reduction treatment, and the release treatment are sequentially switched,
A dry gas refining facility comprising a sulfur component recovery means for recovering the sulfur component released in the release process . A coal gasifier that generates coal gasification gas by reaction of coal and oxidant;
The dry gas purification facility according to claim 1 or claim 2, wherein the coal gasification gas generated in the coal gasification furnace is purified to obtain a fuel gas;
Combustion means for burning the fuel gas obtained in the dry gas purification facility;
A gas turbine that obtains power by expanding combustion gas from the combustion means;
A steam turbine for obtaining power by expanding the steam obtained by recovering the heat of the exhaust gas of the gas turbine.
Coal gasification combined power generation facility characterized by that.

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