JP5688748B2 - Dry gas refining equipment and coal gasification combined power generation equipment - Google Patents

Description

  The present invention relates to a dry gas refining facility and a coal gasification combined power generation facility, and in particular, selectively oxidizes ammonia in a combustible gas such as a coal gasification gas (a combustible compound containing carbon atoms, a sulfide, a gas containing ammonia; the same applies hereinafter). It is useful when applied to an apparatus having an ammonia decomposition apparatus that decomposes by reaction.

  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 such coal as a fuel, an integrated coal gas 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 gasification furnace contains impurities such as sulfides and ammonia, impurities that affect subsequent equipment, and trace components, so the gas purification equipment removes impurities from the coal gasification gas. (Hereinafter, the gas supplied to the gas turbine after gas purification is referred to as “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 the evaporation and condensation of moisture, the actual situation is that there is a limit to high 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. Since the coal gasification gas can be purified at a high temperature by refining the coal gasification gas in a dry manner, the high temperature fuel gas after purification can be supplied to the gas turbine while suppressing the temperature and pressure from rising and falling. .

  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 maintenance of temperature and pressure, and in consideration of the influence on subsequent devices, and it has not been put into practical use.

  On the other hand, dry ammonia decomposition method using selective oxidation reaction to remove ammonia content in combustible gas to contribute to efficient operation without reducing thermal efficiency of gasification facilities such as coal gasification combined power generation facilities Has been proposed (see, for example, Patent Document 2). This is the addition of a small amount of oxygen to selectively promote the decomposition reaction of ammonia in combustible gas into nitrogen and water, suppressing the oxidation reaction of carbon monoxide to carbon dioxide and the oxidation reaction of hydrogen to water. At the same time, it is devised to suppress side reactions in which compounds containing carbon atoms such as carbon monoxide are decomposed into carbon on the catalyst surface.

  In the purification of combustible gas, including the above-mentioned coal gasification gas, which contains both flammable components and ammonia, the decomposition reaction of ammonia is promoted and other side reactions that cause deterioration of other combustible gases are suppressed as much as possible. It is important to do. Even in the case disclosed in Patent Document 2, the decomposition reaction of ammonia in the combustible gas is promoted, and at the same time, the side reaction of other combustible components is suppressed, but the deterioration of the combustible gas is more effectively suppressed. The appearance of a technique that can favorably promote the decomposition reaction of ammonia in the combustible gas is awaited.

  Applying dry gas refining considering the maintenance of temperature and pressure and considering the influence on the subsequent equipment together with ammonia decomposition suppressing the side reaction as described above, for example, biomass, heavy oil, municipal waste This problem also exists in the case of refining combustible gas obtained by thermally decomposing a fuel such as a gasification furnace. Since all of these materials contain nitrogen compounds in the raw material, ammonia is generated and mixed into the fuel when the fuel is gasified. However, if the combustible gas mixed with ammonia is burned as it is, This is because fuel NOx is generated by the reaction of nitrogen and oxygen.

JP 2005-171148 A JP 2006-56935 A

  In view of the above prior art, the present invention can perform ammonia decomposition by selective oxidation reaction well, and realizes purification of combustible 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 is an object of the present invention to provide a dry gas purification facility and a coal gasification combined power generation facility having the same.

The first aspect of the present invention for achieving the above object is as follows:
A desulfurization device that removes sulfides in the combustible gas by a dry method in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point, and an ammonia content in the combustible gas desulfurized by the desulfurization device. Is decomposed by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposition catalyst, and a combustible gas disposed on the upstream side of the ammonia decomposition device and on the inlet side of the ammonia decomposition device And a temperature adjusting means for adjusting the temperature of the combustible gas after desulfurization so that the temperature of the deoxidation reaction is a temperature obtained by subtracting a temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction , the catalyst is characterized in that the zeolite 10-membered ring structure or 12-membered ring structure is constructed by by supporting nickel as carrier In the formula gas purification equipment.
Here, the temperature increase due to the ammonia selective oxidation reaction is the temperature increase due to the entire reaction including side reactions such as oxidation of carbon monoxide and hydrogen.

  According to this aspect, the temperature of the combustible gas desulfurized by the dry method is adjusted by the temperature adjusting means, and the selective oxidation reaction in the ammonia decomposition apparatus is performed at a temperature range of 200 ° C. to 500 ° C. where the decomposition efficiency is good. Can be made.

As a result, the combustible gas can be desulfurized while maintaining a high temperature without lowering the temperature of the combustible gas, and ammonia decomposition by selective oxidation can be efficiently performed. In addition, since the combustible gas supplied to the ammonia decomposition apparatus is desulfurized, the ammonia decomposition catalyst is not deteriorated by sulfides.
Furthermore, this aspect provides equipment that uses an ammonia decomposition catalyst that can suppress side reactions such as oxidation of carbon monoxide and hydrogen and carbon deposition as much as possible while also having good ammonia decomposition performance by selective oxidation.
As a result, the degradation of the combustible gas accompanying the ammonia decomposition treatment can be reduced as much as possible at the same time as the highly efficient ammonia decomposition .

The second aspect of the present invention is:
In the dry gas purification facility described in the first aspect, a mercury remover that removes mercury contained in the combustible gas whose ammonia content has been decomposed by the ammonia decomposing apparatus, and the combustible gas introduced into the mercury remover. A dry gas purification facility having a heat exchanger that raises the temperature of the combustible gas after removing mercury as a heat medium.

  In this aspect, since the mercury remover is added together with the heat exchanger on the downstream side of the ammonia decomposing apparatus of the first aspect, not only the mercury removal by the mercury remover is possible, but also the combustible gas for mercury removal. Even when the temperature is lowered, this heat can be recovered by the heat exchanger.

  As a result, heat recovery associated with mercury removal processing can be performed, and mercury can be removed together with sulfide and ammonia without losing the thermal energy of the combustible gas.

The third aspect of the present invention is:
A desulfurization device that removes sulfides in the combustible gas and a temperature of the combustible gas desulfurized by the desulfurization device by a dry method in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point. A temperature adjusting means for adjusting the temperature of the gas, a mercury remover for removing mercury contained in the combustible gas whose temperature is adjusted by the temperature adjusting means, and a combustible gas introduced after the mercury is removed by the mercury remover An ammonia decomposition apparatus that decomposes the ammonia content in the catalyst by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposition catalyst, and the combustible gas introduced into the mercury remover as a heat medium. After the mercury removal so that the temperature of the combustible gas on the inlet side of the cracking apparatus becomes a temperature obtained by subtracting the temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction. Which has a heat exchanger for raising the temperature of the combustible gas, the ammonia decomposition catalyst is dry, characterized in that the zeolite 10-membered ring structure or 12-membered ring structure is constructed by by supporting nickel as carrier Located in gas purification facility.

  According to this aspect, since the mercury remover is added to the upstream side of the ammonia decomposing apparatus of the first aspect together with the heat exchanger, not only the mercury removal by the mercury remover becomes possible, but also for mercury removal. Even when the temperature of the combustible gas is lowered, this heat can be recovered by the heat exchanger.

  Furthermore, since the mercury remover is provided on the upstream side of the ammonia decomposing apparatus, it is possible to effectively prevent deterioration of the ammonia decomposing catalyst due to mercury. Here, the mercury removal system is not affected by the ammonia content in the combustible gas.

As a result, heat recovery associated with mercury removal treatment can be performed while preventing degradation of the ammonia decomposition catalyst due to mercury, and mercury can be removed together with sulfide and ammonia without losing the heat energy of the combustible gas. .
Furthermore, this aspect provides equipment that uses an ammonia decomposition catalyst that can suppress side reactions such as oxidation of carbon monoxide and hydrogen and carbon deposition as much as possible while also having good ammonia decomposition performance by selective oxidation.
As a result, the degradation of the combustible gas accompanying the ammonia decomposition treatment can be reduced as much as possible at the same time as the highly efficient ammonia decomposition .

The fourth aspect of the present invention is:
A desulfurization device that removes sulfides in the combustible gas by a dry method in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point, and an ammonia content in the combustible gas desulfurized by the desulfurization device. Is decomposed by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposition catalyst, and a combustible gas disposed on the upstream side of the ammonia decomposition device and on the inlet side of the ammonia decomposition device A temperature adjusting means for adjusting the temperature of the combustible gas after desulfurization so that the temperature of the gas is a temperature obtained by subtracting the temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction; and upstream of the temperature adjusting means It is arranged on the side, which has a heat exchanger for raising the temperature of the combustible gas after ammonia decomposition of combustible gas to be introduced as heating medium in the temperature control unit, before Ammonia decomposition catalyst is a zeolite of 10-membered ring structure or 12 membered ring structure in a dry gas purification equipment, characterized in that those constituted by supporting nickel as a carrier.

  According to this aspect, a part of the heat that falls between the desulfurization apparatus and the ammonia decomposition apparatus of the first aspect is recovered from the dry gas purification equipment by, for example, the combustible gas supplied to the turbine by the heat exchanger. You can also

As a result, in addition to the operation and effect of the first aspect, there is also an operation and effect that higher temperature combustible gas can be supplied to subsequent devices such as a turbine.
Furthermore, this aspect provides equipment that uses an ammonia decomposition catalyst that can suppress side reactions such as oxidation of carbon monoxide and hydrogen and carbon deposition as much as possible while also having good ammonia decomposition performance by selective oxidation.
As a result, the degradation of the combustible gas accompanying the ammonia decomposition treatment can be reduced as much as possible at the same time as the highly efficient ammonia decomposition .

According to a fifth aspect of the present invention,
In the dry gas purification facility described in the fourth aspect, a mercury remover that removes mercury contained in the combustible gas whose ammonia content has been decomposed by the ammonia decomposing apparatus, and the combustible gas introduced into the mercury remover. A dry gas purification facility having a heat exchanger that raises the temperature of the combustible gas after removing mercury as a heat medium.

  According to this aspect, a part of the heat that falls between the desulfurization apparatus and the ammonia decomposition apparatus of the second aspect is recovered from the dry gas purification facility by, for example, the combustible gas supplied to the turbine by the heat exchanger. You can also

  As a result, in addition to the operation and effect of the second aspect, there is also an operation and effect that higher temperature combustible gas can be supplied to subsequent devices such as a turbine.

The sixth aspect of the present invention is:
A desulfurization device that removes sulfides in the combustible gas and a temperature of the combustible gas desulfurized by the desulfurization device by a dry method in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point. A temperature adjusting means for adjusting the temperature of the gas, a mercury remover for removing mercury contained in the combustible gas whose temperature is adjusted by the temperature adjusting means, and a combustible gas introduced after the mercury is removed by the mercury remover An ammonia decomposition apparatus that decomposes the ammonia content in the catalyst by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposition catalyst, and the combustible gas introduced into the mercury remover as a heat medium. After the mercury removal so that the temperature of the combustible gas on the inlet side of the cracking apparatus becomes a temperature obtained by subtracting the temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction. A first heat exchanger that raises the temperature of the combustible gas and an upstream side of the temperature adjustment means, and raises the temperature of the combustible gas after ammonia decomposition using the combustible gas introduced into the temperature adjustment means as a heat medium. A dry gas refining facility comprising a second heat exchanger and the ammonia decomposition catalyst comprising nickel supported on a zeolite having a 10-membered ring structure or a 12-membered ring structure It is in.

  According to this aspect, a part of the heat that falls between the desulfurization apparatus and the ammonia decomposition apparatus of the third aspect is recovered from the dry gas purification equipment by, for example, the combustible gas supplied to the turbine by the heat exchanger. You can also

As a result, in addition to the operation and effect of the third aspect, there is also an operation and effect that higher temperature combustible gas can be supplied to subsequent equipment such as a turbine.
Furthermore, this aspect provides equipment that uses an ammonia decomposition catalyst that can suppress side reactions such as oxidation of carbon monoxide and hydrogen and carbon deposition as much as possible while also having good ammonia decomposition performance by selective oxidation.
As a result, the degradation of the combustible gas accompanying the ammonia decomposition treatment can be reduced as much as possible at the same time as the highly efficient ammonia decomposition .

The seventh aspect of the present invention is
In the dry gas purification facility described in the first, second, fourth, or fifth aspect, the temperature adjusting means and the ammonia decomposing apparatus have a structure in which both are integrated, and a predetermined number of stages are provided. The dry gas refining equipment is configured to perform temperature adjustment and ammonia decomposition.

  In this embodiment, ammonia decomposition treatment is performed in multiple stages together with temperature adjustment.

  As a result, variations in temperature distribution in the ammonia decomposition catalyst can be leveled as much as possible, and the decomposition reaction can proceed at the most reasonable temperature. Also, the integration can contribute to the overall downsizing of the facility.

According to an eighth aspect of the present invention, in the dry gas purification facility according to any one of the first to seventh aspects, a halide in the combustible gas purified by the dry method is disposed upstream of the desulfurization apparatus. It is in a dry gas refining facility characterized in that a halide removing device for removing is disposed.

  According to this aspect, the halide in the combustible gas is removed in a dry manner and further upstream of the desulfurization apparatus.

  As a result, it is possible to remove the adverse effects of halides on downstream equipment and the like while maintaining high thermal efficiency of the gas purification facility.

The ninth aspect of the present invention provides
The coal gasification furnace which produces | generates coal gasification gas by reaction of coal and an oxidizing agent, and the 1st to 9th aspect which refine | purifies the coal gasification gas produced | generated by the said coal gasification furnace Dry gas purification equipment, combustion means for burning the combustible gas obtained in the dry gas purification equipment, a gas turbine for obtaining power by expanding the combustion gas from the combustion means, and exhaust gas of the gas turbine And a steam turbine for obtaining power by expanding the steam obtained by recovering the heat of the coal gasification combined power generation facility.

  In this aspect, the coal gasification gas is well purified by dry gas purification equipment, and fuel gas in which side reactions such as carbon deposition are suppressed is supplied to the gas turbine, and combined power generation by the steam turbine is performed.

  As a result, high-efficiency power generation can be performed with high-quality and high-temperature fuel gas.

  Since the dry gas purification equipment according to the present invention performs the entire gas purification process in a dry manner, the predetermined good gas purification can be performed while maintaining the high temperature state without reducing the temperature of the combustible gas. Can do. In particular, ammonia can be decomposed by selective oxidation at a reaction temperature of 200 ° C. to 500 ° C., so that the ammonia content in the combustible gas can be decomposed most efficiently.

  Furthermore, compared with wet gas purification, effects such as reduction of facility costs, chemical costs, treatment costs and reduction of environmental burdens due to unnecessary waste treatment and wastewater treatment facilities can be obtained.

  Moreover, the coal gasification combined cycle power generation facility according to the present invention can perform high-efficiency power generation using high-quality, high-temperature coal gasification gas highly purified by the dry gas purification facility.

It is a block diagram which shows the coal gasification gas combined cycle power generation equipment which concerns on embodiment of this invention. It is a block diagram which shows the dry-type gas purification equipment which concerns on the 1st Embodiment of this invention which extracted a part of FIG. It is a block diagram which shows the dry-type gas purification equipment which concerns on the 2nd Embodiment of this invention which extracted a part of FIG. It is a block diagram which shows the dry-type gas purification equipment which concerns on the 3rd Embodiment of this invention which extracted a part of FIG. It is a block diagram which shows the dry-type gas purification equipment which concerns on the 4th Embodiment of this invention which extracted a part of FIG. It is a block diagram which shows the dry-type gas purification equipment which concerns on the 5th Embodiment of this invention which extracted a part of FIG. It is a block diagram which shows the dry-type gas purification equipment which concerns on the 6th Embodiment of this invention which extracted a part of FIG. It is a graph which shows the ammonia decomposition characteristic for every trial manufacture catalyst. Is a graph showing the production characteristics of the N _{2 O} per each test catalyst. It is a graph which shows the production | generation characteristic of HCN for every prototype catalyst. CO for each trial catalyst is a graph showing the reaction-product properties of CO _2. Is a graph showing the reaction-product properties of H _2, CH ₄ for each trial catalyst. It is the schematic which shows the multistage-type ammonia decomposing apparatus which performs ammonia decomposition in multistage.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<Embodiment of coal gasification combined cycle facility>
FIG. 1 is a block diagram showing a coal gasification combined cycle facility according to an embodiment of the present invention. As shown in the figure, the combined coal gasification combined power generation facility 1 includes a coal gasification furnace 2 in which carbon atoms are generated by a reaction between coal and an oxidant (oxygen, air) at a high temperature. A coal gasification gas g, which is a combustible gas containing combustible compounds, sulfides, ammonia and the like, is generated. The coal gasification gas g is dedusted by a dust removing means (not shown), adjusted to a predetermined temperature by the heat exchanger 3, and further purified by removing impurities from the dry gas purification equipment 4. The refined coal gasification gas is supplied to the combustor 6 of the turbine equipment 5 as the fuel gas f. Here, 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, the output of the steam turbine 11 is also added by this steam.

  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 a high-temperature fuel gas f.

  Here, a more specific configuration of the dry gas purification facility will be described based on each embodiment shown in FIGS. Note that, in each embodiment, the same parts are denoted by the same reference numerals, and redundant description is omitted. Moreover, although the temperature shown in each figure is gas temperature, these are an example to the last, and, of course, it is not limited to these temperatures. Furthermore, each temperature is expressed as an ideal state with no heat loss.

<First embodiment of dry gas purification equipment>
FIG. 2 is a block diagram showing the dry gas purification facility according to the first embodiment of the present invention. As shown in the figure, the dry gas refining equipment 41 according to the present embodiment includes a halide removing device 20 that removes halide contained in the coal gasification gas g generated in the coal gasification furnace 2 at the most upstream part. The desulfurization device 21 for removing sulfides contained in the coal gasification gas g from which the halide has been removed, the temperature adjustment device 22 for adjusting the coal gasification gas g after desulfurization to a predetermined temperature, and the temperature are adjusted. An ammonia decomposing apparatus 23 for decomposing ammonia contained in the coal gasification gas g by selective oxidation in the presence of air a (presence of oxygen in an amount that the coal gasification gas g cannot be vapor-phase combusted); And a post-filter 24 that is a physical filtration device (for example, a sintered filter) disposed in the section, from which halides, sulfides, and ammonia are removed in order from the upstream side, and other trace components Including The fuel gas f purified is removed by post filter 24 the particulate matter is arranged to supply to the turbine system 5.

More specifically, in the halide removing apparatus 20, for example, sodium aluminate (NaAlO ₂ ), which is a sodium-based halide absorbent as an alkali-based material, is formed into a pellet and used. Some hydrogen chloride (HCl) and hydrogen fluoride (HF) can be removed simultaneously.

In the desulfurization apparatus 21, a zinc ferrite desulfurization agent, which is a zinc oxide-based desulfurization agent, can be formed into a honeycomb shape and used suitably. By bringing the coal gasification gas g into contact with the zinc ferrite desulfurization agent, sulfur sulfide (H ₂ S), carbonyl sulfide (COS) and the like can be removed to a very low concentration by a dry method. Here, since the zinc ferrite desulfurization agent itself has the function of a hydrogenation catalyst, the performance can be exerted on organic sulfur compounds including carbonyl sulfide (COS).

In the case of this embodiment, the temperature adjusting device 22 functions as a cooler that cools the coal gasification gas g at a high temperature (for example, 450 ° C.) after desulfurization to a coal gasification gas g at a low temperature (220 ° C.). This supplies, for example, steam generated at an arbitrary steam generation source of the coal gasification combined power generation facility 1 (see FIG. 1) and absorbs sensible heat of the high-temperature coal gasification gas g after desulfurization . It can implement | achieve suitably by comprising in this way.

  The ammonia decomposition apparatus 23 is filled with a catalyst for ammonia decomposition by a selective oxidation reaction. As this catalyst, a catalyst having a 10-membered ring structure or a 12-membered ring structure as a support is suitable. Here, the 10-membered ring or 12-membered ring means a membered ring structure having 10 or 12 oxygen atoms. In zeolites having an eight-membered ring structure with a small pore diameter, oxygen having a large molecular size is unlikely to enter the pores, and therefore, selective oxidation reaction with ammonia does not easily occur in the pores. On the other hand, zeolite having a structure with a 10-membered ring or more having a large pore diameter allows oxygen to easily enter the pores, so that the selective oxidation reaction with ammonia in the pores is promoted. However, the larger the pore diameter, the easier the growth of carbon and the polymerization of the carbon-containing compound in the pores, and the easier the carbon deposition occurs. Therefore, in order to promote the decomposition reaction by selective oxidation of ammonia and at the same time suppress the reaction of carbon monoxide and the like being decomposed to carbon on the surface of the catalyst, the pore structure has a 10-membered ring structure or a 12-membered ring structure. Zeolite having a structure is preferable, and zeolite having a 10-membered ring structure is most preferable. Examples of the zeolite having a 10-membered ring structure include ZSM-5 zeolite and ZSM-11 zeolite. Further, Y-type zeolite is suitable as the zeolite having a 12-membered ring structure.

  As the silica / alumina ratio is increased, the crystal stability of the zeolite is improved, and the structure of the zeolite is maintained even under high temperature and high steam conditions, so that the catalyst life is extended. A transition metal such as nickel is suitable as the active substance of the catalyst.

  Other than zeolite, a carrier that can be expected to have a similar function is silica-alumina.

  That is, the catalyst in this embodiment can be suitably formed by supporting nickel with a zeolite having a 10-membered ring structure or a 12-membered ring structure or silica / alumina as a support.

  Here, there is no particular limitation on the shape of the catalyst. Any of a powder form, a pellet form, a honeycomb form and the like may be used. Also, there is no particular limitation on the active substance loading form. That is, a transition metal such as nickel may be supported on at least the surface of a carrier having a predetermined shape, or a transition metal may be supported on a powder carrier and used as it is or in a granular form. Further, it may be formed into a slurry shape, poured into a mold, fired, and formed into a predetermined shape such as a honeycomb.

  Further, it is desirable that the amount of oxygen added for promoting selective oxidation and at the same time suppressing the reaction in which the combustible components are decomposed is 0.75 mol / mol or more and 15 mol / mol or less in terms of a molar ratio with respect to ammonia. In order to avoid gas phase combustion, it is necessary to make the concentration below the critical oxygen concentration. Incidentally, in the case of coal gasification gas containing 1000 ppm of ammonia, the oxygen concentration with a molar ratio to ammonia of 15 mol / mol is 1.5 vol%. Here, the critical oxygen concentration refers to an oxygen concentration at which a combustible gas cannot be vapor-phase combusted at a predetermined temperature and pressure. Hydrogen is 1.5 vol%, carbon monoxide is 5.6 vol%, and methane is 12. 1 vol%, ammonia is more than that. Since this critical oxygen concentration changes depending on the temperature and pressure of the reaction field, it is important to adjust it according to the operating conditions.

  Here, in this embodiment, the temperature adjustment device 22 adjusts the inlet side gas temperature of the ammonia decomposition device 23 to 220 ° C. so that the ammonia decomposition reaction by selective oxidation is performed at 300 ° C., but this is due to selective oxidation. This is because an increase in the surface temperature of the ammonia decomposition catalyst due to the heat of reaction during ammonia decomposition (in this case, 80 ° C. (= 300 ° C.-220 ° C.)) is expected. Therefore, in general, the gas temperature on the inlet side of the ammonia decomposing apparatus 23 by the temperature adjusting apparatus 22 is determined from the temperature of the catalyst layer that decomposes ammonia most efficiently while suppressing the deterioration of fuel and carbon deposition. What is necessary is just to adjust to the temperature which subtracted the temperature rise by a selective oxidation reaction which becomes settled with the addition amount of oxygen or air, and the reaction rate of oxygen.

  Further, the temperature range of the reaction temperature of the ammonia decomposition treatment in this embodiment is preferably 200 ° C. to 500 ° C., and more preferably 200 ° C. to 450 ° C. The grounds for this point will be described in detail later, along with experiments that serve as the basis for the findings.

  In this embodiment configured as described above, the halogen removal and desulfurization treatment is performed at 450 ° C. (operating temperature exceeding the dew point) by a dry method, and the ammonia decomposition treatment by the selective oxidation reaction is performed at 300 ° C. The particulate matter is captured and removed by the stationary filter 24.

  As a result, the temperature and pressure of the coal gasification gas g are maintained, impurities and trace components that adversely affect subsequent equipment such as the turbine equipment 5 are reliably removed, and high-temperature fuel gas is supplied to the turbine equipment 5. Can do. Further, in this embodiment, ammonia decomposition by selective oxidation reaction is performed at 300 ° C., so that side reactions that degrade the combustible components of the coal gasification gas g can be suppressed and ammonia can be decomposed satisfactorily.

That is, when the temperature adjusting device 22 adjusts the inlet side temperature of the ammonia decomposition device 23 to 220 ° C. and the coal gasification gas g supplied together with a predetermined amount of air a comes into contact with the ammonia decomposition catalyst,
4NH ₃ + 3O ₂ → 2N ₂ + 6H ₂ O
The selective oxidation reaction of ammonia is promoted, and at the same time other ammonia reactions (formation of nitrogen compounds such as nitrogen monoxide, nitrogen dioxide, nitrous oxide, hydrogen cyanide) and fuel gas reactions (hydrogen, carbon monoxide) The ammonia content contained in the coal gasification gas g is decomposed satisfactorily while effectively suppressing reactions such as oxidation of carbon, formation of carbon and hydrocarbons.

  In this embodiment, the halide removing device 20 and the post filter 24 may be provided as necessary.

<Second embodiment of dry gas purification equipment>
FIG. 3 is a block diagram showing a dry gas purification facility according to the second embodiment of the present invention. As shown in the figure, the dry gas purification facility 42 according to this embodiment removes mercury contained in the coal gas g after ammonia decomposition on the downstream side of the ammonia decomposition apparatus 23 of the first embodiment shown in FIG. The mercury remover 25 and the heat exchanger 26 to be added are added.

  More specifically, the mercury remover 25 can suitably apply a copper-based absorbent that mainly absorbs mercury and absorbs mercury as a mercury remover, and brings the coal gasification gas g into contact with the copper-based absorbent. To absorb and remove mercury. As the mercury absorbent, it is also possible to use an impregnated activated carbon that carries a chemically reactive component and removes mercury by adsorbing a salt generated by a chemical reaction with mercury. Here, since the copper-based absorbent and the impregnated activated carbon exhibit adsorption performance at a low temperature (for example, 180 ° C.), the mercury remover 25 has a high temperature (for example, the reaction heat when decomposing the ammonia component by selective oxidation). , 300 ° C.), the coal gasification gas g is cooled to 180 ° C. by the heat exchanger 26 and supplied.

  On the other hand, the cooling medium of the heat exchanger 26 is a low-temperature (for example, 180 ° C.) fuel gas f in which impurities are filtered by the post filter 24 and the temperature is raised by the heat exchanger 26. The sensible heat of the coal gasification gas g at a high temperature (about 450 ° C.) before being supplied is used to raise the temperature of the fuel gas f at a low temperature (about 180 ° C.). Can be recovered.

  For this reason, according to this embodiment, not only can the mercury contained in the coal gasification gas g after ammonia decomposition be removed, but also the temperature of the coal gasification gas g introduced into the mercury remover 25 can be controlled. Even when sensible heat is recovered to raise the temperature of the fuel gas f and a copper-based absorbent or the like having a low operating temperature is applied, temperature control for the operating temperature of the mercury remover 25 and high temperature maintenance of the fuel gas f are maintained. Can be made compatible.

<Third embodiment of dry gas purification equipment>
FIG. 4 is a block diagram showing a dry gas purification facility according to the third embodiment of the present invention. As shown in the figure, the dry gas purification equipment 43 according to the present embodiment removes mercury contained in the coal gas g after desulfurization on the upstream side of the ammonia decomposition apparatus 23 of the first embodiment shown in FIG. A mercury remover 25 and a heat exchanger 26 are added. Here, the configuration itself of the mercury remover 25 and the heat exchanger 26 is the same as that of the second embodiment shown in FIG. However, the heat exchanger 26 of this embodiment lowers the coal gasification gas g adjusted to the inlet temperature (for example, 220 ° C.) of the ammonia decomposing device 23 to a predetermined low temperature (for example, 180 ° C.) suitable for the mercury remover 25. Therefore, the coal gas at a low temperature (for example, 180 ° C.) after mercury removal so that the temperature on the inlet side of the ammonia decomposition device 23 becomes a predetermined temperature (for example, 220 ° C.) using the coal gasification gas g as a heat medium. The chemical gas is heated. That is, the heat exchanger 26 collects the sensible heat of the coal gasification gas g that has been cooled for the mercury removal treatment, and transfers the sensible heat to the ammonia decomposition device 23 that performs the treatment at a higher temperature (for example, 300 ° C.). A gasification gas g is supplied.

  In this embodiment, not only can mercury contained in the coal gasification gas g after desulfurization be removed, but also sensible heat for controlling the temperature of the coal gasification gas g introduced into the mercury remover 25 is ammonia. Even when a low-operating temperature copper-based absorbent or the like is recovered to raise the temperature of the coal gasification gas g supplied to the cracking device 23, temperature control with respect to the operating temperature of the mercury remover 25 The high temperature maintenance of the coal gasification gas g can be made compatible.

  Furthermore, in this embodiment, since the mercury remover 25 is disposed on the upstream side of the ammonia decomposition device 23, deterioration of the ammonia decomposition catalyst due to mercury can be effectively prevented.

<Fourth embodiment of dry gas purification equipment>
FIG. 5 is a block diagram showing a dry gas purification facility according to the fourth embodiment of the present invention. As shown in the figure, the dry-type gas purification equipment 44 according to this embodiment is obtained by adding a heat exchanger 27 to the first embodiment shown in FIG. This heat exchanger 27 is disposed upstream of the temperature adjusting device 22, and finally the desulfurized coal gasification gas g introduced into the temperature adjusting device 22 is used as a heat medium, and finally the post filter 24 after ammonia decomposition. The particulate matter is removed and the temperature of the fuel gas f supplied to the turbine equipment 5 is raised.

  According to this embodiment, in addition to the operations and effects of the first embodiment, the fuel that recovers a part of the heat that falls between the desulfurization device 21 and the ammonia decomposition device 23 and supplies it to the turbine equipment 5 is also provided. The temperature of the gas f can be raised. As a result, it can contribute to the efficiency improvement as the whole power generation equipment.

<Fifth embodiment of dry gas purification equipment>
FIG. 6 is a block diagram showing a dry gas purification facility according to the fifth embodiment of the present invention. As shown in the figure, the dry gas purification equipment 45 according to this embodiment is obtained by adding a heat exchanger 27 to the second embodiment shown in FIG. This heat exchanger 27 is disposed on the upstream side of the temperature control device 22, and finally the coal gasification gas g after desulfurization introduced into the temperature control device 22 is used as a heat medium, and finally the post-filter 24 after mercury removal. The particulate matter is removed and the temperature of the fuel gas f supplied to the turbine equipment 5 is raised.

  According to this embodiment, in addition to the operations and effects of the second embodiment, fuel that recovers a part of the heat that falls between the desulfurization device 21 and the ammonia decomposition device 23 and supplies the fuel to the turbine equipment 5 is also provided. The temperature of the gas f can be raised. As a result, similar to the fourth embodiment, it is possible to contribute to improving the efficiency of the entire power generation facility.

<Sixth embodiment of dry gas purification equipment>
FIG. 7 is a block diagram showing a dry gas purification facility according to the sixth embodiment of the present invention. As shown in the figure, a dry gas purification facility 46 according to this embodiment is obtained by adding a heat exchanger 27 to the third embodiment shown in FIG. This heat exchanger 27 is disposed on the upstream side of the temperature adjusting device 22, and the coal gasification gas g after desulfurization introduced into the temperature adjusting device 22 is used as a heat medium, and finally the post filter 24 is used after removing ammonia. The particulate matter is removed and the temperature of the fuel gas f supplied to the turbine equipment 5 is raised.

  According to this embodiment, in addition to the operations and effects of the third embodiment, the fuel that recovers a part of the heat that falls between the desulfurization device 21 and the ammonia decomposition device 23 and supplies it to the turbine equipment 5 is also provided. The temperature of the gas f can be raised. As a result, similar to the fourth and fifth embodiments, it is possible to contribute to improving the efficiency of the entire power generation facility.

<Basic experiments related to ammonia decomposition treatment>
The ammonia decomposition catalyst in the dry gas purification equipment 41 to 46 according to each embodiment as described above has a transition metal (for example, nickel) supported on zeolite or silica / alumina having a 10-membered ring structure or a 12-membered ring structure. Although the fact that it is suitable and that the temperature range of the ammonia decomposition treatment temperature range is preferably 200 ° C. to 500 ° C., more preferably 200 ° C. to 450 ° C., the knowledge that provides the basis for this point has been obtained. The basic experiment and the discussion of the results are mentioned.

Nickel (Ni) is selected as the active component of the ammonia decomposition catalyst, which is a prototype catalyst used in this experiment, and alumina (Al ₂ O ₃ ) and silica-alumina (SiO ₂ · Al ₂ O ₃ ) are used as carriers. ZSM-5 zeolite (ZSM-5), beta zeolite (Beta), and Y-type zeolite (Y) were used. A list of such prototype catalysts is shown in Table 1.

A combustible gas simulating coal gasification gas was formed by contacting the ammonia decomposition catalyst having a particle size of 2 to 3 mm with the prototype catalyst shown in Table 1. More specifically, the composition of the combustible gas is simulated by simulating the gas composition at the outlet of the desulfurization unit of a coal gasification combined power generation facility using a dry-type carbon dioxide enriched air-blown entrained bed gasification furnace. Oxygen was added at an oxygen / fuel ratio (O ₂ / Fuel) of 0.008 mol / mol (approximately 8 mol / mol in molar ratio to NH ₃ ). The experiment was performed under the conditions of a space velocity (SV) of 20000 h ⁻¹ and a pressure of 0.9 MPa.

  Table 2 shows the experimental conditions at this time.

When supplying the combustible gas in this experiment, first, the temperature of the ammonia decomposition catalyst layer was raised to 150 ° C. in a nitrogen (N ₂ ) stream and the temperature was stabilized, and then the combustible gas and oxygen were supplied. Hold until stable. Next, after the temperature of the ammonia decomposition catalyst layer was raised to a predetermined temperature, the operation for maintaining the constant temperature for 20 minutes and acquiring data was repeated up to 600 ° C. every 50 ° C. The data at this time are ammonia (NH ₃ ), hydrogen cyanide (HCN), nitrogen monoxide (NO), nitrogen dioxide (NO ₂ ), dinitrogen monoxide (N ₂ O), hydrogen (H ₂ ) in the cracked gas. ), Methane (CH ₄ ) to butane (C ₄ H ₁₀ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), nitrogen (N ₂ ), and oxygen (O ₂ ).

The experimental results are shown in FIGS. FIG. 8 shows the conversion rate of ammonia (NH ₃ ) to nitrogen (N ₂ ) with respect to the catalyst temperature. Note that the conversion rate was subtracted from decomposed ammonia (NH _3), the resulting hydrogen cyanide (HCN), nitrogen monoxide (NO), nitrogen dioxide (NO ₂₎ and dinitrogen monoxide _(N 2 O) concentration As a calculation using a predetermined calculation formula.

Also, FIG. 9 shows the production rate of dinitrogen monoxide (N ₂ O), FIG. 10 shows the hydrogen cyanide (HCN) production rate with respect to the catalyst temperature, and FIG. 11 shows the carbon monoxide (CO) and carbon dioxide (CO) at the catalyst outlet. the concentration for the catalyst temperature of _2), FIG. 12 shows the respective concentrations to the catalyst temperature of the hydrogen _{(H 2)} and methane (CH _4). Among these, the simultaneous occurrence of a decrease in CO concentration and an increase in CO ₂ concentration in a state where O ₂ has disappeared is evidence that carbon deposition has occurred. Although not shown in the figure, almost no NO, NO ₂ , ethane to butane were produced, and O _{2 at} the catalyst outlet disappeared at 450 to 500 ° C. or higher.

  Accordingly, the characteristics shown in FIGS. 9 to 12 can be regarded as characteristics with respect to the catalyst temperature of the degree of deterioration of the combustible gas in the predetermined selective oxidation reaction, in other words, the degree of suppression of side reactions.

  With reference to the experimental results shown in FIGS. 8 to 12, the ammonia decomposition reaction by selective oxidation in this embodiment is preferably performed at a catalyst temperature of 200 ° C. to 500 ° C., more preferably 200 ° C. to 450 ° C. I understand.

Further, when examining the catalyst itself, the Ni-supported catalyst having both SiO ₂ and Al ₂ O ₃ as the main carrier constituents exhibits good ammonia decomposition activity, and at the same time, consumption of combustible gas, carbon deposition, CH ₄ , It is considered that side reactions such as N ₂ O and HCN generation can be suppressed. In particular, Ni / ZSM-5 has a high NH ₃ decomposition activity and a side reaction suppressing ability. In addition, Ni / Y and Ni / SiO ₂ .Al ₂ O ₃ can suppress side reactions such as ammonia decomposition activity and carbon precipitation in a wide temperature range.

Thus, based on the results of this experiment, where it has become clear that Ni / ZSM-5 has significant NH ₃ selective oxidative decomposition activity and can suppress side reactions such as carbon deposition over a wide temperature range, When using ZSM-5, which is a zeolite with a member ring structure, Y zeolite, which is a zeolite with a 12 member ring structure, and a catalyst in which a transition metal (for example, nickel) is supported on a support which is SiO ₂ · Al ₂ O ₃ It is considered that the ammonia contained can be satisfactorily decomposed while suppressing side reactions in a wide temperature range and suppressing deterioration as a combustible gas as much as possible.

  In addition, the temperature range in which harmful side reactions can be effectively suppressed while maintaining a good decomposition rate of ammonia in the catalyst used in the experiment including the above catalyst is preferably 200 ° C. to 500 ° C., more preferably 200 ° C. to 450 ° C. It has been found that ° C is more preferred.

<Other embodiments>
In general, the temperature of the combustible gas after the desulfurization treatment is preferably higher from the viewpoint of the thermal efficiency of the dry gas purification facility. Therefore, the outlet side temperature of the desulfurization apparatus is often higher than the inlet side temperature of the ammonia decomposition apparatus. In other words, the temperature adjusting device 22 often functions as a cooler. However, the desulfurization by the dry method only needs to be able to treat the combustible gas at a temperature above the dew point, and therefore does not exclude the case where the temperature rises in relation to the inlet temperature of the ammonia treatment apparatus. In short, it may be configured so that it can be adjusted to the inlet temperature of the ammonia decomposition apparatus set from the viewpoint of ammonia decomposition efficiency and the like.

  Furthermore, the ammonia decomposing apparatus may be integrated with the temperature adjusting apparatus and configured in multiple stages. That is, as shown in FIG. 13, from the inlet side, the first-stage temperature adjustment device 28A, the first-stage ammonia decomposition device 28B, the second-stage temperature adjustment device 28C, and the second-stage ammonia decomposition device 28D. Are connected in tandem and integrated.

  In such a multistage ammonia cracker 28, for example, if the amount of catalyst in the first stage ammonia cracker 28B is halved compared to the case where the catalyst is not multistage, the high temperature after desulfurization (on the inlet side of the first stage temperature regulator 28A) When the combustible gas (for example, 450 ° C.) is supplied together with the air a for the selective oxidation reaction, the temperature adjustment device 28A may drop the temperature to a higher temperature (for example, 260 ° C.) than the case where it is not multistage and supply it to the ammonia decomposition device 28B. . As a result, since the amount of catalyst is small in the ammonia decomposing apparatus 28B, the temperature rise due to the reaction is also small, and ammonia is decomposed by selective oxidation at a predetermined temperature (for example, 300 ° C.). Next, as a result, the combustible gas whose temperature has been increased (for example, 300 ° C.) is supplied to the second-stage temperature adjusting device 28C to be lowered to a predetermined temperature (for example, 260 ° C.), and the remaining catalyst amount is filled. If supplied to the second stage ammonia decomposition apparatus 28D, similarly, ammonia is decomposed by selective oxidation at a predetermined temperature (for example, 300 ° C.).

  As a result, in the multistage ammonia decomposing apparatus 28, variations in temperature distribution in the ammonia decomposing apparatuses 28B and 28D can be leveled as much as possible, and the decomposition reaction can proceed at the most reasonable temperature. Also, the integration can contribute to the overall downsizing of the facility.

  Furthermore, although each said embodiment demonstrated the coal gasification combined cycle power generation equipment using coal gasification gas as combustible gas, of course, it is not restricted to this. The combustible gas is not limited to coal gasification gas, and is not particularly limited as long as it contains a combustible compound containing carbon atoms, sulfide, ammonia, etc., and the combustible gas can be used as equipment using this kind of combustible gas. There are no particular restrictions on the equipment that is used for dry purification. The other combustible gas may be, for example, a gas obtained by thermally decomposing fuel such as biomass, heavy oil, and municipal waste in a gasification furnace, as long as it is a facility that purifies and uses this type of gas. Various power generation facilities and gas facilities for chemical synthesis may be used.

  INDUSTRIAL APPLICABILITY The present invention can be effectively used in an industrial field that uses equipment for purifying combustible gas such as coal gasification gas in a dry manner.

DESCRIPTION OF SYMBOLS 1 Coal gasification combined cycle power generation facility 2 Coal gasification furnace 4 Dry-type gas purification facility 5 Turbine facility 6 Combustor 7 Gas turbine 11 Steam turbine 12 Generator 16 Compressor 20 Halide removal device 21 Desulfurization device 22 Temperature adjustment device 23 Ammonia decomposition Equipment 25 Mercury removers 26, 27 Heat exchanger 28 Multistage ammonia cracking equipment 28A, 28C Temperature control equipment 28B, 28D Ammonia cracking equipment 41-46 Dry gas purification equipment

Claims (9)

A desulfurization apparatus for removing sulfides in the combustible gas by a dry process in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point;
An ammonia decomposing apparatus for decomposing an ammonia content in the combustible gas desulfurized by the desulfurizing apparatus by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposing catalyst;
The temperature of the combustible gas disposed on the upstream side of the ammonia decomposing apparatus and the inlet side of the ammonia decomposing apparatus is set to a temperature obtained by subtracting the temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction. Temperature adjusting means for adjusting the temperature of the combustible gas after desulfurization ,
The dry gas refining equipment , wherein the ammonia decomposition catalyst is constituted by supporting nickel with a zeolite having a 10-membered ring structure or a 12-membered ring structure as a carrier . In the dry gas purification equipment according to claim 1,
A mercury remover for removing mercury contained in the combustible gas whose ammonia content has been decomposed by the ammonia decomposition apparatus;
A dry gas refining facility comprising: a heat exchanger that raises the temperature of the combustible gas after mercury removal using the combustible gas introduced into the mercury remover as a heat medium. A desulfurization apparatus for removing sulfides in the combustible gas by a dry process in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point;
Temperature adjusting means for adjusting the temperature of the combustible gas desulfurized by the desulfurization apparatus to a predetermined temperature;
A mercury remover for removing mercury contained in the combustible gas whose temperature is adjusted by the temperature adjusting means;
An ammonia decomposing apparatus that decomposes the ammonia content in the combustible gas introduced after the mercury is removed by the mercury removing device by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposing catalyst;
Using the combustible gas introduced into the mercury remover as a heat medium, the temperature of the combustible gas on the inlet side of the ammonia decomposition apparatus is obtained by subtracting the temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction. And having a heat exchanger that raises the temperature of the combustible gas after mercury removal ,
The dry gas refining equipment , wherein the ammonia decomposition catalyst is constituted by supporting nickel with a zeolite having a 10-membered ring structure or a 12-membered ring structure as a carrier . A desulfurization apparatus for removing sulfides in the combustible gas by a dry process in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point;
An ammonia decomposing apparatus for decomposing an ammonia content in the combustible gas desulfurized by the desulfurizing apparatus by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposing catalyst;
The temperature of the combustible gas disposed on the upstream side of the ammonia decomposing apparatus and the inlet side of the ammonia decomposing apparatus is set to a temperature obtained by subtracting the temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction. Temperature adjusting means for adjusting the temperature of the combustible gas after desulfurization;
A heat exchanger that is disposed upstream of the temperature adjusting means and heats the combustible gas after ammonia decomposition using the combustible gas introduced into the temperature adjusting means as a heat medium ; and
The dry gas refining equipment , wherein the ammonia decomposition catalyst is constituted by supporting nickel with a zeolite having a 10-membered ring structure or a 12-membered ring structure as a carrier . In the dry gas purification facility according to claim 4,
A mercury remover for removing mercury contained in the combustible gas whose ammonia content has been decomposed by the ammonia decomposition apparatus;
A dry gas refining facility comprising: a heat exchanger that raises the temperature of the combustible gas after mercury removal using the combustible gas introduced into the mercury remover as a heat medium. A desulfurization apparatus for removing sulfides in the combustible gas by a dry process in which the temperature of the combustible gas to be purified is maintained at a temperature higher than the dew point;
Temperature adjusting means for adjusting the temperature of the combustible gas desulfurized by the desulfurization apparatus to a predetermined temperature;
A mercury remover for removing mercury contained in the combustible gas whose temperature is adjusted by the temperature adjusting means;
An ammonia decomposing apparatus that decomposes the ammonia content in the combustible gas introduced after the mercury is removed by the mercury removing device by a selective oxidation reaction at a reaction temperature of 200 ° C. to 500 ° C. using an ammonia decomposing catalyst;
Using the combustible gas introduced into the mercury remover as a heat medium, the temperature of the combustible gas on the inlet side of the ammonia decomposition apparatus is obtained by subtracting the temperature increase due to the selective oxidation reaction from the reaction temperature of the selective oxidation reaction. A first heat exchanger for raising the temperature of the combustible gas after mercury removal,
A second heat exchanger that is disposed on the upstream side of the temperature adjusting means and raises the temperature of the combustible gas after ammonia decomposition using the combustible gas introduced into the temperature adjusting means as a heat medium ;
The dry gas refining equipment , wherein the ammonia decomposition catalyst is constituted by supporting nickel with a zeolite having a 10-membered ring structure or a 12-membered ring structure as a carrier . In the dry gas purification facility according to claim 1, claim 2, claim 4 or claim 5,
The dry gas purification, wherein the temperature adjusting means and the ammonia decomposing apparatus have a structure in which both are integrated, and are configured to perform predetermined temperature adjustment and ammonia decomposition in multiple stages. Facility. In the dry-type gas purification facility according to any one of claims 1 to 7 ,
A dry gas purification facility characterized in that a halide removing device for removing halides in combustible gas purified by the dry method is disposed upstream of the desulfurization device. A coal gasifier that generates coal gasification gas by reaction of coal and oxidant;
The dry gas purification equipment according to any one of claims 1 to 8 , wherein the coal gasification gas generated in the coal gasification furnace is purified.
Combustion means for combusting the combustible gas obtained in the dry gas purification facility;
A gas turbine that obtains power by expanding combustion gas from the combustion means;
A coal gasification combined cycle power plant comprising: a steam turbine that obtains power by expanding steam obtained by recovering heat of exhaust gas of the gas turbine.

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