JP6319526B1 - Power generation equipment - Google Patents

Abstract

Provide power generation facilities that can safely use ammonia gas as fuel. The power generation facility 1 of the present invention supplies a boiler 6 that burns fuel, a denitration facility 90 that decomposes nitrogen oxides contained in the exhaust gas generated by the combustion, and ammonia gas that is used in the denitration facility 90. Ammonia gas supply equipment 2, a pipe 130 connecting the ammonia gas supply equipment 2 and the denitration equipment 90, branching from the ammonia gas fuel pipe equipment 3 connected to the boiler 6, and the ammonia gas fuel use An ammonia gas outflow pipe 151a for allowing the ammonia gas in the pipe equipment 3 to flow out to the ammonia gas 8 provided in the denitration equipment 90;

Description

  The present invention relates to a power generation facility.

Conventionally, boilers of power generation facilities such as thermal power plants generate high-temperature and high-pressure steam using heat obtained by burning fossil fuels such as coal, natural gas, light oil, and heavy oil in a burner. However, burning these fossil fuels generates carbon dioxide, which causes global warming. For this reason, in recent years, there has been a movement to suppress carbon dioxide in the form of carbon credits (emission allowances).
For example, LNG (liquefied natural gas) has less carbon dioxide emissions than LPG (liquefied petroleum gas). For this reason, LNG is used as a fuel. A gas fuel such as LNG needs to be liquefied for convenience during transportation. However, in the case of LNG, since it is necessary to make a low temperature state of about -180 degrees in order to liquefy, liquefaction is not easy and equipment costs are also required.
For this reason, utilization of ammonia gas has been proposed as a fuel that does not generate carbon dioxide (see, for example, Patent Document 1). Ammonia liquefies at about minus 33 degrees. For this reason, for example, liquefaction is easy compared to LNG that requires about minus 180 for liquefaction, and the cost of equipment is low.

Japanese Patent Laid-Open No. 2006-183840

In the combustor in which gas such as coal gasification gas is burned as the main fuel, the apparatus described in Patent Document 1 is used to input ammonia gas used for the denitration apparatus as additional fuel when the output is reduced. is there.
However, ammonia gas is erosive and toxic. For this reason, when using the ammonia gas used in a denitration apparatus for combustion, the device which prevents the outflow etc. of ammonia gas to the atmosphere is required.

  An object of the present invention is to provide a power generation facility that can safely use ammonia gas as a fuel.

The present invention provides the following to solve the above-described problems.
(1) A boiler that burns fuel, a denitration facility that decomposes nitrogen oxides contained in exhaust gas generated by the combustion, an ammonia gas supply facility that supplies ammonia gas used in the denitration facility, and the ammonia Branching from a pipe connecting the gas supply facility and the denitration facility, the ammonia gas fuel piping facility connected to the boiler, and the ammonia gas in the ammonia gas fuel piping facility are supplied to the ammonia gas supply facility. A power generation facility comprising: an ammonia gas outflow pipe for flowing out into an ammonia gas absorption portion provided.

(2) The ammonia gas fuel pipe facility may include a purge pipe into which a purge gas other than ammonia gas flows.

(3) A control unit that controls the operation of the power generation facility is provided, and the control unit sets the destination of the ammonia gas supplied from the ammonia gas supply facility to the denitration facility or the ammonia gas fuel piping facility. When the ammonia gas flows from the ammonia gas supply facility to the denitration facility, the ammonia gas flows from the ammonia gas supply facility to the ammonia gas fuel piping facility rather than the pressure setting in the ammonia gas supply facility. In this case, the pressure setting in the ammonia gas supply facility may be increased.

(4) The ammonia gas fuel piping facility may have shutoff valves on the upstream side and the downstream side, respectively.

  According to the present invention, it is possible to provide a power generation facility that can be safely used by using ammonia gas as a fuel.

It is the schematic of the power generation equipment of embodiment. It is a figure explaining four gas burners of the uppermost step among four burners. It is a flowchart explaining operation of the power generation equipment by a control part. It is a figure explaining bypass operation of ammonia gas supply equipment at the time of ammonia gas combustion. It is a figure explaining operation which substitutes for nitrogen gas from ammonia gas in piping equipment for ammonia gas fuel. It is a figure explaining operation at the time of completion of operation which replaces nitrogen gas into ammonia gas in piping equipment for ammonia gas fuel. It is a figure explaining the pressure | voltage rise operation of the piping installation for ammonia gas fuels. It is a figure explaining ignition operation of piping equipment for ammonia gas fuel. It is a figure explaining flow volume adjustment operation of piping equipment for ammonia gas fuel. It is a figure explaining stop operation of piping equipment for ammonia gas fuel. It is a figure explaining operation which replaces ammonia gas in piping equipment for ammonia gas fuel with nitrogen gas.

  Hereinafter, the power generation equipment 1 of the embodiment of the present invention will be described. FIG. 1 is a schematic view of a power generation facility 1 according to an embodiment. The power generation facility 1 of the embodiment is a system capable of combusting ammonia gas, but is a co-firing power generation facility 1 capable of combusting other than ammonia gas such as pulverized coal, oil, natural gas or BOG (boil off gas).

  The power generation facility 1 includes an ammonia gas supply facility 2, an ammonia gas fuel piping facility 3, a boiler 6, a denitration facility 90, and a gas fuel supply unit that supplies gas fuel other than ammonia gas via the gas fuel piping 170. 70, and a control unit 7 for controlling the whole.

[Ammonia gas supply equipment 2]
The ammonia gas supply facility 2 includes a storage tank 10, a vaporizer 20, an accumulator 30, an ammonia gas absorption unit 80, and the like. The ammonia gas absorption unit 80 is a water storage tank that absorbs ammonia gas emitted from the blow valve 81 and the like provided in the ammonia gas supply facility 2 into water.

(Storage tank 10)
The storage tank 10 stores liquid ammonia that has been pressurized and liquefied, and is connected to the vaporizer 20 via a pipe 110. The pipe 110 is branched in two directions on the way. A vaporizer start valve 11 and a vaporizer pressure adjustment valve 12 for controlling the pressure in the vaporizer 20 are sequentially arranged in the branched one pipe 110a from the upstream side. The carburetor bypass valve 13 is disposed in the other branched pipe 110b.

(Vaporizer 20)
The vaporizer 20 heats and vaporizes the liquid ammonia supplied from the storage tank 10. In the vaporizer 20, the liquid ammonia is heated and vaporized through a coiled pipe immersed in warm water, and becomes ammonia gas. The downstream side of the vaporizer 20 is connected to the accumulator 30 via a pipe 120.
The pipe 120 is branched in two directions on the way. In one branched pipe 120a, an accumulator starting valve 21 and an accumulator pressure adjusting valve 22 for controlling the pressure in the accumulator 30 are sequentially arranged from the upstream side. An accumulator bypass valve 23 is disposed in the other branched pipe 120b.

(Accumulator 30)
The accumulator 30 is a device that accumulates ammonia gas and stabilizes the pressure. A pipe 130 extends from the downstream side of the accumulator 30. The pipe 130 is branched in two directions. One branched pipe 132 is connected to the header 40. The other branched pipe 131 is connected to the ammonia gas fuel piping facility 3.

[Header 40]
A pipe 140 is connected to the downstream side of the header 40, the pipe 140 is branched into a plurality of denitration pipes 141, 142, and 143, and each of the denitration pipes 141, 142, and 143 has a denitration cutoff valve 41, 42, 43. To the denitration facility 90.

[Denitration equipment 90]
In the denitration facility 90, the denitration pipes 141, 142, and 143 are connected to denitration apparatuses 91, 92, and 93, respectively. The denitration devices 91, 92, and 93 are fed with exhaust gas generated by combustion from the boiler 6, and the ammonia that flows into the denitration pipings 141, 142, and 143 from the piping in which the denitration shutoff valves 41, 42, and 43 are open Using the gas as a reducing agent, nitrogen oxides in the exhaust gas are converted into harmless nitrogen gas and water.

[Piping equipment for ammonia gas fuel 3]
As described above, the pipe 131 branched from the pipe 130 extending from the accumulator 30 is connected to the ammonia gas fuel pipe equipment 3. A shutoff valve 31 is provided on the upstream side of the pipe 131. A purge pipe 133 extending from a purge gas supply unit 37 through which purge gas such as nitrogen gas can flow into the ammonia gas fuel pipe facility 3 is connected via the purge valve 36 on the downstream side of the shutoff valve 31.

  The downstream side of the pipe 131 connected to the purge pipe 133 is branched in two directions. A pressure regulating valve 32 is arranged in one of the branched pipes 131a. A shutoff valve 33 is arranged on the other branched pipe 131b. The pipe 131a and the pipe 131b merge again on the downstream side. The joined pipe 131 is connected to the flow meter 50 via the shut-off valve 34.

  The flow meter 50 measures the flow rate of the gas flowing through the pipe 131. A pipe 150 extends from the downstream side of the flow meter 50. The pipe 150 is branched in two directions. A flow rate adjusting valve 51 is disposed in one branched pipe 150a. A shutoff valve 52 is arranged in the other branched pipe 150b. The pipe 150a and the pipe 150b merge again on the downstream side.

The downstream side of the joined pipe 150 is branched in two directions by the second connection portion 56.
One of the branched pipes is an ammonia gas outflow pipe 151a, and is connected to the ammonia gas absorption unit 80 of the ammonia gas supply facility 2 through the ammonia outflow shutoff valve 55. The ammonia gas absorption unit 80 is a water storage tank as described above, and dissolves ammonia gas in water.
A burner valve 53 is disposed in the other branched ammonia gas supply pipe 151b. A cooling pipe 160 into which cooling air flows is connected via the cooling air valve 61 to the downstream side of the burner valve 53 in the pipe 150.
The ammonia gas outflow pipe 151 a may be branched downstream of the burner valve 53.
The downstream side of the ammonia gas supply pipe 151 b is connected to the first connection part 72 of the gas fuel pipe 170 extending from the gas fuel supply part 70 to the gas burner 62 </ b> A of the boiler 6 via the shutoff valve 54.

[Gas fuel supply unit 70]
The gas fuel supply unit 70 stores LNG (liquefied natural gas). When LNG is liquefied and stored, LNG is vaporized due to natural heat input from the outside, and BOG gas (boil off gas) is generated. In the present embodiment, the gas fuel pipe 170 is a pipe that sends this BOG as fuel to the gas burner 62A.
The gas fuel pipe 170 is connected to the gas burner 62 </ b> A of the boiler 6 on the downstream side of the first connection portion 72. A gas fuel pipe cutoff valve 71 is disposed on the upstream side of the first connection portion 72 in the gas fuel pipe 170.

[Boiler 6]
The boiler 6 is provided with a plurality of burners 62 (in this embodiment, four stages in the height direction (burners 62A, 62B, 62C, 62D) and a plurality of rows (four in each stage in this embodiment). Yes.
FIG. 2 is a diagram for explaining the uppermost four burners 62 </ b> A among the four-stage burners 62. In the present embodiment, gas fuel is supplied to each of the four burners 62A. In addition, coal (pulverized coal) is supplied as fuel from the coal storage unit 75 to the other three-stage burners 62B, 62C, and 62D shown in FIG.

As shown in FIG. 2, the ammonia gas supply pipe 151 b is connected to the gas fuel pipe 170 at the first connection portion 72. The first connection portion 72 is disposed in the vicinity of the gas burner 62A. That is, the distance from the 1st connection part 72 of the gas fuel piping 170 to the gas burner 62A is short. And between the 1st connection part 72 and gas burner 62A, members, such as packing which is easy to be corroded by ammonia gas, are not arranged. Further, in the first connection portion 72, a member that is easily eroded by ammonia gas is not used between the ammonia gas supply pipe 151 b and the gas fuel pipe 170. Further, the gas fuel pipe cutoff valve 71 is disposed in the vicinity of the first connection portion 72 on the upstream side of the first connection portion 72.
Furthermore, the part from the 1st connection part 72 to the gas burner 62A in the gas fuel piping 170 and the part from the gas fuel piping shut-off valve 71 to the 1st connection part 72 are comprised so that it can replace | exchange easily. In addition, a member that is easily corroded by ammonia gas is not used in the shut-off valve and the connection part used in the above-described ammonia gas fuel piping facility 3.
In the present embodiment, the gas supplied to the burner 62E can be switched between ammonia gas and BOG by switching between opening and closing between the cutoff valve 54 and the gas fuel pipe cutoff valve 71.

Next, an example of a method for operating the power generation facility 1 of the present embodiment via the control unit 7 will be described.
(1) Initial state (step S1)
FIG. 1 illustrates an initial state of the power generation facility 1 of the present embodiment. FIG. 3 is a flowchart for explaining the operation of the power generation facility 1 by the control unit 7.
In the initial state,
(I) The carburetor start valve 11 is open.
(Ii) The carburetor bypass valve 13 is closed.
(Iii) The accumulator activation valve 21 is open.
(Iv) The accumulator bypass valve 23 is closed.
(V) The shut-off valve 31 is closed.
In the vaporizer pressure regulating valve 12, for example, the ammonia pressure is set to 0.25 MPa, and in the accumulator pressure regulating valve 22, the ammonia pressure is set to 0.15 MPa.
The liquid ammonia is sent from the storage tank 10 through the pipe 110 and the pipe 110 a to the vaporizer 20 with the pressure adjusted to 0.25 MPa in the vaporizer pressure regulating valve 12.
The ammonia gas vaporized in the vaporizer 20 is sent to the accumulator 30 after the pressure is adjusted to 0.15 MPa in the accumulator pressure regulating valve 22.
0.15 MPa ammonia gas is sent to the header 40 via the pipe 132. However, the denitration shut-off valves 41, 42, 43 are all closed, and the denitration equipment 90 and the header 40 are cut off. Further, since the gas fuel pipe shutoff valve 71 is open, the BOG is being supplied to the gas burner 62A.

  When any of the denitration shutoff valves 41, 42, 43 provided in the denitration pipes 141, 142, 143 is open, the ammonia gas passes through the open denitration shutoff valves 41, 42, 43. The denitration equipment 91, 92, 93 is sent to the corresponding denitration equipment 90. Exhaust gas generated by combustion is sent from the boiler 6 to the denitration apparatuses 91, 92, and 93. Ammonia gas flowing in from the denitration pipes 141, 142, and 143 is used as a reducing agent, and nitrogen oxides in the exhaust gas are harmless. Nitrogen gas and water.

(2) Bypass operation (step S2)
FIG. 4 is a diagram for explaining a bypass operation of the ammonia gas supply facility 2 during ammonia gas combustion. The control unit 7 performs the following control from the state shown in FIG.
(I) The accumulator bypass valve 23 is gradually opened from the closed state.
(Ii) The accumulator starting valve 21 is closed from the open position. Note that the accumulator bypass valve 23 and the accumulator activation valve 21 may be interlocked.
Thereby, the ammonia gas vaporized by the vaporizer 20 is bypassed so as to pass through the pipe 120b without passing through the accumulator pressure regulating valve 22.
The reason for preventing the ammonia gas from passing through the accumulator pressure regulating valve 22 is as follows. The upper limit of the adjustable pressure of the accumulator pressure adjusting valve 22 is 0.3 MPa. When ammonia gas is burned, the ammonia gas pressure at the position where the accumulator pressure regulating valve 22 is arranged is higher than that used in the denitration equipment 90, being 0.3 MPa or more, for example, about 0.45 MPa. It is because it is preferable.

(3) Operation for replacing nitrogen gas with ammonia gas (step S3)
FIG. 5 is a diagram for explaining the operation of replacing the ammonia gas fuel piping facility 3 from nitrogen gas to ammonia gas. The control unit 7 performs the following control from the state of FIG.
(I) The gas fuel pipe shutoff valve 71 is closed. Then, the flow of BOG into the gas burner 62A is blocked.
(Ii) Open the shut-off valve 34 from closed.
(Iii) The pressure of the pressure regulating valve 32 is set to 0.15 MPa. The flow rate of the flow rate adjustment valve 51 is adjusted to 100 kg / h (opening 40%).
(Iv) The shutoff valve 31 is gradually opened from the closed state. As a result, ammonia gas flows into the pipe 150 of the ammonia gas fuel pipe facility 3.
(V) The cooling air valve 61 is closed from open. The cooling air cools the gas burner 62A. By closing the cooling air valve 61 from the open state, the flow of the cooling air is cut off and mixing of the ammonia gas and the air is prevented.
(Vi) The burner valve 53 is gradually opened from the closed state. At this time, the nitrogen previously filled in the pipe 150 and the like is released into the boiler in which the fuel is burning, and the pipes 130 and 150 of the ammonia gas fuel pipe facility 3 are replaced with ammonia gas.
In addition, the ammonia outflow shut-off valve 55 provided in the ammonia gas outflow pipe 151a checks the pressure in the pipe, and when the pressure becomes higher than a predetermined value, it is appropriately opened to let out the ammonia gas.

(4) Operation for completing replacement of nitrogen gas with ammonia gas (step S4)
FIG. 6 is a diagram for explaining the operation at the time of completion of the operation of substituting the ammonia gas fuel piping facility 3 from nitrogen gas to ammonia gas. The control unit 7 performs the following control from the state shown in FIG.
(I) The flow rate of the nitrogen gas is checked with the flow meter 50 to 0.7 kg.
The capacity of the piping from the upstream end to the downstream end of the ammonia gas fuel piping facility 3 of this embodiment is about 1 m ³ . 1 m ³ of nitrogen gas is about 0.7 kg. The passage of 0.7 kg of gas through the flow meter 50 indicates that almost all of the nitrogen gas in the piping in the ammonia gas fuel piping facility 3 has flowed out and replaced with ammonia gas. Although not shown in an accurate scale in the figure, the actual distance from the flow meter 50 to the downstream end of the ammonia gas fuel piping facility 3 is very small compared to the distance to the upstream end. Therefore, the capacity in the pipe from the flow meter 50 to the downstream end of the ammonia gas fuel piping facility 3 is negligible.
(Ii) The burner valve 53 is closed from open.
(Iii) The cooling air valve 61 is opened from the closed state. In addition, the burner valve 53 and the cooling air valve 61 can be interlocked. By closing the burner valve 53 and opening the cooling air valve 61, the cooling air is sent to the gas burner 62A.
(Iv) The shut-off valve 34 is closed from open.
In addition, the ammonia outflow shut-off valve 55 provided in the ammonia gas outflow pipe 151a checks the pressure in the pipe, and when the pressure becomes higher than a predetermined value, it is appropriately opened to let out the ammonia gas.

(5) Interlock setting change (step S5)
When the ammonia gas generated in the ammonia gas supply facility 2 of the power generation facility 1 is used in the denitration facility 90, the ammonia gas supply facility 2 may be provided with an interlock. In this case, the set pressure of the interlock is relatively low, and when ammonia gas is used as the fuel as in the present embodiment, the set pressure may be too low. Therefore, the control unit 7 appropriately changes the interlock pressure setting of the ammonia gas supply facility 2.

(6) Step-up operation (step S6)
FIG. 7 is a diagram for explaining the pressure increasing operation of the ammonia gas fuel piping facility 3. The control unit 7 performs the following control from the state of FIG.
(I) The pressure set value of the pressure regulating valve 32 of the ammonia gas fuel piping facility 3 is changed from 0.15 MPa to 0.35 MPa.
(Ii) The pressure set value of the vaporizer pressure regulating valve 12 before the vaporizer 20 is changed from 0.25 MPa to 0.45 MPa.
Here, the pressure set value of the vaporizer pressure regulating valve 12 before the vaporizer 20 is 0.45 MPa, which is larger than 0.35 MPa which is the pressure set value of the pressure regulating valve 32 of the ammonia gas fuel piping equipment 3. This is because it is easier to control when the pressure is inclined.

(7) Ignition operation (step S7)
FIG. 8 is a diagram for explaining the ignition operation of the ammonia gas fuel piping facility 3. The control unit 7 performs the following control from the state of FIG.
(I) The shut-off valve 34 is opened from the closed state.
(Ii) The cooling air valve 61 is closed from open.
(Iii) The burner valve 53 is slowly opened from the closed state to ignite the gas burner 62A. At this time, it is assumed that the pressure is reduced by about 0.2 MPa.
(Iv) Ignit the gas burner 62A.

(8) Flow rate adjustment (step S8)
FIG. 9 is a view for explaining the flow rate adjusting operation of the ammonia gas fuel piping facility 3. The control unit 7 performs the following control from the state of FIG.
(I) After confirming that combustion is stable, the flow rate is adjusted appropriately. The supply amount of the ammonia gas varies depending on the number of burners for burning ammonia. For example, the flow rate when supplying ammonia gas to one burner is about 450 kg / h.

(9) Stop operation (step S9)
FIG. 10 is a diagram for explaining a stop operation of the ammonia gas fuel piping facility 3. The control unit 7 performs the following control from the state of FIG.
(I) Lower the flow rate setting of the flow rate adjustment valve 51 to a flow rate of 100 kg / h.
(Ii) The pressure setting of the pressure adjustment valve 32 is returned from 0.35 MPa to 0.1 MPa.
(Iii) The burner valve 53 is closed from open. As a result, the supply of ammonia gas is stopped, and the gas burner 62A is extinguished. At this time, the pressure of ammonia gas may rise to 0.3 MPa.
(Iv) The cooling air valve 61 is opened from the closed state. Thereby, cooling air is sent to the gas burner 62A, and the gas burner 62A is cooled.
(V) The shutoff valve 34 is closed from the open state to stop the inflow of ammonia gas into the ammonia gas fuel piping facility 3.
(Vi) The vaporizer starting valve 11 is closed from open to stop the vaporization of liquid ammonia.
Here, when the ammonia gas is again supplied from the ammonia gas fuel piping facility 3 to the gas burner 62A to burn the ammonia gas (NO in step S10), the vaporizer start valve 11 is opened and the process returns to step S6. .
Further, when the ammonia combustion operation is not performed for a certain period of time at night or the like, the ammonia outflow shutoff valve 55 may be opened. By doing so, ammonia gas can be released when the pressure in the ammonia gas fuel piping facility 3 rises.

(10) Replacement Operation FIG. 11 shows the operation when the ammonia gas in the ammonia gas fuel piping facility 3 is replaced with nitrogen gas when the ammonia combustion is stopped, for example, when it is not used for a long time (step S10, YES). It is a figure explaining. The control unit 7 performs the following control from the state shown in FIG. 10 (step S11).
(I) The shutoff valve 31 is closed from open.
(Ii) The cooling air valve 61 is closed from open.
(Iii) The shut-off valve 54 is changed from open to closed. (I), (ii), and (iii) prevent the ammonia outflow from the ammonia gas fuel piping facility 3.
(Iv) The gas fuel pipe shutoff valve 71 is opened from the closed state. Thereby, BOG is sent to the gas burner 62A.
(V) The burner valve 53 is opened from the closed state.
(Vi) The shut-off valve 34 is opened from the closed state. The inside of the piping facility 3 for ammonia gas fuel communicates by (v) and (vi).
(Vii) The ammonia outflow shutoff valve 55 is opened from the closed state. Thereby, the flow path to the ammonia gas absorption part 80 of ammonia is ensured.
(Viii) The purge valve 36 of the purge pipe 133 is opened from the closed state, and ammonia is replaced with nitrogen gas. The ammonia gas is sent from the ammonia gas outflow pipe 151a to the ammonia gas absorption unit 80. At this time, after confirming 1.4 kg (corresponding to 2 m ³ ) with the flow meter 50, 25 ppm or less is confirmed with an ammonia gas detector, and the replacement is completed. In step 4, the flow rate of 50 kg of nitrogen gas was confirmed by the flow meter 50, but in step S10, the flow rate is doubled by the flow meter. This is to completely replace the ammonia gas with nitrogen gas.

As described above, this embodiment has the following effects.
(1) The power generation facility 1 of the present embodiment includes a boiler 60 that burns fuel, a denitration facility 90 that decomposes nitrogen oxides contained in exhaust gas generated by combustion, and ammonia gas that is used in the denitration facility 90. Ammonia gas fuel piping facility 3 branched from the piping 130 connecting the ammonia gas supply facility 2 to be supplied, the ammonia gas supply facility 2 and the denitration facility 90, and connected to the boiler 60, and a piping for ammonia gas fuel An ammonia gas outflow pipe 151 a is provided for allowing the ammonia gas in the facility 3 to flow out to the ammonia gas absorption unit 80 provided in the denitration facility 90.
According to the present embodiment, ammonia gas can be caused to flow out from the ammonia gas fuel piping facility 3 into the ammonia gas absorption part 80 provided in the ammonia gas supply facility 2, so that the ammonia gas can be prevented from flowing out into the atmosphere. Can be prevented.
Moreover, since ammonia gas flows out into the ammonia gas absorption part 80 of the ammonia gas supply equipment 2, the ammonia gas absorption part 80 can be shared, and there is no extra cost.

(2) The power generation facility 1 of the present embodiment includes a purge piping 133 into which nitrogen gas flows as a purge gas in the ammonia gas fuel piping facility 3.
According to the present embodiment, by purging the ammonia gas fuel piping facility 3 with nitrogen gas, the ammonia gas present in the ammonia gas fuel piping facility 3 can be sent to the ammonia gas absorbing portion 80, so that the ammonia gas fuel Disassembling and inspection work for the piping equipment 3 can be performed.

(3) In the power generation facility 1 of the present embodiment, the control unit 7 performs the pressure setting in the ammonia gas supply facility 2 when ammonia gas flows from the ammonia gas supply facility 2 to the denitration facility 90 in step S2 and step S6. The pressure setting in the ammonia gas supply facility 3 when the ammonia gas flows from the ammonia gas supply facility 2 into the ammonia gas fuel piping facility 3 is increased.
As a result, the ammonia gas feed pressure can be increased during ammonia gas combustion, so that sufficient ammonia gas can be sent for combustion and a sufficient injection pressure in the burner section can be secured.

(4) In the power generation facility 1 of the present embodiment, the ammonia gas fuel piping facility 3 has shutoff valves 31 and 54 on the upstream side and the downstream side, respectively. By closing these shut-off valves 31 and 54 and purging the ammonia gas fuel piping 3 with nitrogen gas, the ammonia gas can be sent to the ammonia gas absorption unit 80, so that the ammonia gas can be prevented from flowing into the atmosphere. Is prevented.

(5) The power generation facility 1 of this embodiment includes a gas burner 61E connected to a gas fuel pipe 170 that supplies gas fuel other than ammonia gas. The ammonia gas fuel piping facility 3 is connected to the gas fuel piping 170. Further, a gas fuel pipe shutoff valve 71 is provided on the upstream side of the first connecting portion 72 to which the ammonia gas fuel pipe equipment 3 is connected in the gas fuel pipe 170.
According to the present embodiment, closing the gas fuel pipe shutoff valve 71 prevents ammonia gas from flowing into the gas fuel pipe 170 upstream of the gas fuel pipe shutoff valve 71.
Therefore, deterioration and damage due to erosion of the gas fuel pipe 170 in the gas fuel pipe 170 upstream of the gas fuel pipe cutoff valve 71 and the gas fuel supply unit 70 due to ammonia are prevented.

(6) The power generation facility 1 of this embodiment is a mixed combustion power generation facility including a burner that burns fuel such as coal other than gas fuel. Therefore, various fuels can be burned.

(7) A power generation facility in a power plant, for example, a power generation facility for coal, includes an ammonia gas supply facility and a denitration facility. Some of such power generation facilities are provided with a gas burner that burns BOG or natural gas, such as the gas burner 61E of the present embodiment.
According to this embodiment, ammonia can be combusted by adding the ammonia gas fuel piping facility 3 to such an existing power generation facility.

(8) When fossil fuel is burned, carbon dioxide is generated. However, in this embodiment, ammonia gas can be used as fuel, so that the amount of carbon dioxide emitted from the power generation facility can be reduced. In particular, by applying the present invention to a power generation facility that burns coal with a large amount of carbon dioxide emission as a fuel, it can help to prevent global warming and provide a more environmentally friendly power generation facility.

(9) In this embodiment, ammonia gas having a liquefaction temperature of about minus 33 degrees at atmospheric pressure can be used as a fuel. Therefore, liquefaction and storage are relatively easy, and the liquefaction storage equipment is compared with liquid hydrogen or LNG. And cheap.

DESCRIPTION OF SYMBOLS 1 Power generation equipment 2 Ammonia gas supply equipment 3 Piping equipment for ammonia gas fuel 6 Boiler 7 Control part 10 Storage tank 11 Vaporizer starting valve 12 Vaporizer pressure regulating valve 13 Vaporizer bypass valve 20 Vaporizer 21 Accumulator starting valve 22 Accumulator pressure regulation Valve 23 Accumulator bypass valve 30 Accumulator 31, 33, 34, 52, 54 Shutoff valve 32 Pressure adjustment valve 36 Purge valve 37 Purge gas supply unit 40 Header 50 Flow meter 51 Flow control valve 53 Burner valve 55 Ammonia outflow shutoff valve 60A Burner 61 Cooling air valve 62A Gas burner 70 Gas fuel supply part 71 Gas fuel piping shutoff valve 72 First connection part 80 Ammonia gas absorption part 90 Denitration equipment 110, 110a, 110b, 120, 120a, 120b, 130, 131, 131a 131b, 132,140,150,150a, 150b piping 133 purge pipe 151a ammonia gas outlet pipe 151b ammonia supply pipe 160 cooling pipe 170 gas fuel pipe

Claims (4)

A boiler that burns fuel;
A denitration facility for decomposing nitrogen oxides contained in the exhaust gas generated by the combustion;
An ammonia gas supply facility for supplying ammonia gas used in the denitration facility;
Branching from a pipe connecting the ammonia gas supply equipment and the denitration equipment, and piping equipment for ammonia gas fuel connected to the boiler;
An ammonia gas outflow pipe for causing the ammonia gas in the ammonia gas fuel piping equipment to flow out to an ammonia gas absorption section provided in the ammonia gas supply equipment;
Power generation equipment comprising. The ammonia gas fuel piping equipment includes a purge pipe for flowing a purge gas other than ammonia gas,
The power generation facility according to claim 1. A control unit for controlling the operation of the power generation facility,
The controller is
The destination of the ammonia gas supplied from the ammonia gas supply facility is switched between the denitration facility or the ammonia gas fuel piping facility,
Than the pressure setting in the ammonia gas supply facility when ammonia gas flows into the denitration facility from the ammonia gas supply facility,
Increasing the pressure setting in the ammonia gas supply facility when ammonia gas flows from the ammonia gas supply facility to the ammonia gas fuel piping facility;
The power generation facility according to claim 1 or 2. The ammonia gas fuel piping equipment has shutoff valves on the upstream side and the downstream side,
The power generation facility according to any one of claims 1 to 3.

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