JPWO2019003317A1 - Power generation equipment - Google Patents

Abstract

Providing power generation facilities that can be safely used with ammonia gas as fuel. The power generation facility 1 of the present invention supplies a boiler 6 for burning fuel, a denitration facility 90 for decomposing nitrogen oxides contained in the exhaust gas generated by the combustion, and ammonia gas used in the denitration facility 90 Ammonia gas fuel piping system 3 which is branched from the ammonia gas supply system 2, the piping 130 connecting the ammonia gas supply system 2 and the denitrification system 90, and is connected to the boiler 6, and for the ammonia gas fuel The ammonia gas outflow piping 151a which makes the ammonia gas in the piping installation 3 flow out to the ammonia gas 8 provided in the said denitration equipment 90 is provided.

Description

  The present invention relates to a power generation facility.

Conventionally, a boiler of a power generation facility such as a thermal power plant generates high-temperature high-pressure steam using heat obtained by burning a fossil fuel such as coal, natural gas, light oil, heavy oil or the like with a burner. However, burning these fossil fuels generates carbon dioxide, which causes global warming. For this reason, in recent years there has been a move to curb carbon dioxide in the form of carbon credits (emission allowances).
For example, LNG (liquefied natural gas) produces less carbon dioxide than LPG (liquefied petroleum gas). For this reason, LNG is used as a fuel. Gas fuels, such as LNG, need to be liquefied for convenience in transportation. However, in the case of LNG, liquefaction is not easy because the temperature needs to be in a low temperature state of about -180 degrees in order to liquefy, and equipment cost also increases.
For this reason, utilization of ammonia gas is proposed as fuel which does not generate carbon dioxide (for example, refer to patent documents 1). Ammonia liquefies at around -33 ° C. For this reason, for example, liquefaction is easier as compared to LNG which requires about minus 180 for liquefaction, and the cost of equipment is low.

JP, 2016-183840, A

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

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

The present invention provides the following in order to solve the above-mentioned problems.
(1) A boiler for burning fuel, a NOx removal facility for decomposing nitrogen oxides contained in exhaust gas generated by the combustion, an ammonia gas supply facility for supplying ammonia gas used in the NOx removal facility, and the ammonia Ammonia gas fuel piping equipment for ammonia gas fuel, which is branched from the pipe connecting the gas supply equipment and the denitrification equipment and connected to the boiler, and ammonia gas in the ammonia gas fuel piping equipment are connected to the ammonia gas supply equipment Ammonia gas outflow piping made to flow out to an ammonia gas absorption part provided.

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

(3) The control unit is configured to control the operation of the power generation facility, and the control unit is configured to send the destination of the ammonia gas supplied from the ammonia gas supply facility to the denitration facility or the ammonia gas fuel piping facility. The ammonia gas flows from the ammonia gas supply facility into the ammonia gas fuel piping facility than the pressure setting in the ammonia gas supply facility when the ammonia gas is supplied from the ammonia gas supply facility to the NOx removal facility. The pressure setting in the ammonia gas supply facility may be increased.

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

  According to the present invention, it is possible to provide a power generation facility which can safely use ammonia gas as fuel.

It is the schematic of the power generation equipment of embodiment. It is a figure explaining four gas burners of the top step among 4 steps of 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 replaces with nitrogen gas from ammonia gas in piping installation for ammonia gas fuel. It is a figure explaining the operation at the time of completion of operation which replaces with nitrogen gas from the ammonia gas in piping installation for ammonia gas fuel. It is a figure explaining pressure | voltage rise operation of the piping installation for ammonia gas fuel. It is a figure explaining the ignition operation of the piping installation for ammonia gas fuel. It is a figure explaining flow rate adjustment operation of piping installation for ammonia gas fuel. It is a figure explaining stop operation of piping installation for ammonia gas fuel. It is a figure explaining operation which replaces ammonia gas in piping installation 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 of the embodiment. The power generation facility 1 according to the embodiment is a system capable of combusting ammonia gas, but is a co-fired power generation facility 1 capable of burning other than pulverized coal, oil, natural gas or ammonia gas such as BOG (boil off gas).

  The power generation facility 1 is a gas fuel supply unit that supplies gaseous fuel other than ammonia gas via the ammonia gas supply facility 2, the ammonia gas fuel piping facility 3, the boiler 6, the denitration facility 90, and the gas fuel piping 170. 70, and a control unit 7 that controls the entire system.

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

(Storage tank 10)
The storage tank 10 stores pressurized and liquefied liquid ammonia, and is connected to the vaporizer 20 through a pipe 110. The pipe 110 is branched in two directions along the way. In one branched pipe 110a, a vaporizer start valve 11 and a vaporizer pressure control valve 12 for controlling the pressure in the vaporizer 20 are sequentially disposed from the upstream side. A vaporizer 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, liquid ammonia is heated through the inside of a coiled pipe immersed in warm water and vaporized to be 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 along the way. An accumulator start valve 21 and an accumulator pressure control valve 22 for controlling the pressure in the accumulator 30 are sequentially disposed from the upstream side in one branched pipe 120 a. 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 pipe arrangement 3.

[Header 40]
The pipe 140 is connected to the downstream side of the header 40, and the pipe 140 is branched into a plurality of denitration pipes 141, 142, 143, and the denitration pipes 141, 142, 143 respectively have denitration shutoff valves 41, 42, 43. It is connected to the denitrification equipment 90 through.

[DeNOx Equipment 90]
In the NOx removal facility 90, NOx removal pipes 141, 142 and 143 are connected to NOx removal units 91, 92 and 93, respectively. The exhaust gas generated by combustion from the boiler 6 is fed into the denitration devices 91, 92, 93, and ammonia is introduced from the piping of the denitration piping 141, 142, 143 in which the denitration shutoff valves 41, 42, 43 are open. Using the gas as a reducing agent, nitrogen oxides in the exhaust gas are converted into harmless nitrogen gas and water.

[Ammonia gas fuel piping system 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 arrangement 3. A shutoff valve 31 is provided upstream of the pipe 131. On the downstream side of the shutoff valve 31, a purge pipe 133 extending from a purge gas supply unit 37 capable of flowing a purge gas such as nitrogen gas into the ammonia gas fuel piping installation 3 is connected via a purge valve 36.

  The downstream side of the connection portion of the pipe 131 to which the purge pipe 133 is connected is branched in two directions. A pressure control valve 32 is disposed in one of the branched pipes 131a. A shutoff valve 33 is disposed in the other branched pipe 131b. The pipe 131 a and the pipe 131 b rejoin on the downstream side. The joined pipe 131 is connected to the flow meter 50 via the shutoff 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 piping 150 is branched in two directions along the way. A flow control valve 51 is disposed in one of the branched pipes 150a. A shutoff valve 52 is disposed in the other branched pipe 150b. The pipe 150 a and the pipe 150 b rejoin on the downstream side.

The downstream side of the joined pipe 150 is branched in two directions by the second connection portion 56.
One branched pipe is an ammonia gas outflow pipe 151 a, and is connected to the ammonia gas absorbing unit 80 of the ammonia gas supply facility 2 via an ammonia outflow blocking valve 55. As described above, the ammonia gas absorbing unit 80 is a water storage tank, and dissolves ammonia gas in water.
A burner valve 53 is disposed in the other branched ammonia gas supply pipe 151b. On the downstream side of the burner valve 53 in the pipe 150, a cooling pipe 160 to which cooling air is introduced is connected via a cooling air valve 61.
The ammonia gas outflow piping 151 a may branch downstream of the burner valve 53.
The downstream side of the ammonia gas supply pipe 151 b is connected to the first connection portion 72 of the gas fuel pipe 170 extending from the gas fuel supply unit 70 to the gas burner 62 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, etc., and BOG off gas is generated. In the present embodiment, the gas fuel pipe 170 is a pipe that sends the BOG as a fuel to the gas burner 62A.
The gas fuel pipe 170 is connected to the gas burner 62 A of the boiler 6 at the downstream side of the first connection portion 72. A gas fuel pipe shutoff valve 71 is disposed upstream of the first connection portion 72 in the gas fuel pipe 170.

[Boiler 6]
In the boiler 6, a plurality of stages of burners 62 (four stages in the height direction in the present embodiment (burners 62A, 62B, 62C, 62D) and a plurality of rows (four in each stage in the present embodiment) are arranged There is.
FIG. 2 is a view for explaining the four burners 62A of the uppermost stage among the four stages of the burners 62. As shown in FIG. In the present embodiment, gas fuel is supplied to each of the four burners 62A. In addition, coal (pulverized coal) is supplied as a 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. And this 1st connection part 72 is arrange | positioned in the vicinity of gas burner 62A. That is, the distance from the first connection portion 72 of the gas fuel pipe 170 to the gas burner 62A is short. And between the 1st connection part 72 and gas burner 62A, members, such as packing which are easily corroded by ammonia gas, are not arranged. Further, in the first connection portion 72, a member susceptible to attack by the ammonia gas is not used between the ammonia gas supply pipe 151b and the gas fuel pipe 170. Further, the gas fuel pipe shutoff 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 portion from the first connection portion 72 to the gas burner 62A in the gas fuel piping 170 and the portion from the gas fuel piping shutoff valve 71 to the first connection portion 72 are configured to be easily replaced. In addition, also in the shutoff valve used for the piping installation 3 for ammonia gas fuel mentioned above, and a connection part, the member which is easy to be corroded by ammonia gas is not used.
In the present embodiment, it is possible to switch the gas supplied to the burner 62E between the ammonia gas and the BOG by switching the opening and closing between the shutoff valve 54 and the gas fuel pipe shutoff valve 71.

Next, an example of an operation method of 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. Further, 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 vaporizer start valve 11 is open.
(Ii) The vaporizer bypass valve 13 is closed.
(Iii) The accumulator start valve 21 is open.
(Iv) The accumulator bypass valve 23 is closed.
(V) The shutoff valve 31 is closed.
In the vaporizer pressure control valve 12, for example, the pressure of ammonia is set to 0.25 MPa, and in the accumulator pressure control valve 22, the pressure of ammonia is set to 0.15 MPa.
The liquid ammonia is sent from the storage tank 10 to the vaporizer 20 after the pressure thereof is adjusted to 0.25 MPa in the vaporizer pressure control valve 12 through the piping 110 and the piping 110 a.
The ammonia gas vaporized in the vaporizer 20 is adjusted to a pressure of 0.15 MPa in the accumulator pressure regulating valve 22 and sent to the accumulator 30.
Ammonia gas of 0.15 MPa is sent to the header 40 through the pipe 132. However, the denitration shutoff valves 41, 42, 43 are all closed, and the denitration equipment 90 and the header 40 are separated. Further, since the gas fuel pipe shutoff valve 71 is open, BOG is supplied to the gas burner 62A.

  In addition, when one of the denitration shut off valves 41, 42, 43 provided in each of the denitration pipes 141, 142, 143 is open, the ammonia gas passes through the opened denitration shut off valves 41, 42, 43. , Which are sent to the corresponding ones of the denitrification equipment 90. Exhaust gas produced by combustion from the boiler 6 is sent to the NOx removal devices 91, 92, 93, and the ammonia gas introduced from the NOx removal piping 141, 142, 143 is used as a reducing agent, and nitrogen oxides in the exhaust gas are harmless Converted to nitrogen gas and water.

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

(3) Operation to replace nitrogen gas with ammonia gas (step S3)
FIG. 5 is a view for explaining the operation of replacing the inside of the ammonia gas fuel piping installation 3 with nitrogen gas for the ammonia gas. The control unit 7 performs the following control from the state of FIG.
(I) Close the gas fuel pipe shutoff valve 71. Then, the flow of BOG into the gas burner 62A is shut off.
(Ii) Open the shutoff valve 34 from the closed state.
(Iii) The pressure of the pressure control 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 degree 40%).
(Iv) The shutoff valve 31 is gradually closed and opened. Thus, the ammonia gas flows into the piping 150 of the ammonia gas fuel piping system 3.
(V) The cooling air valve 61 is closed from the open state. The cooling air is cooling the gas burner 62A. By opening and closing the cooling air valve 61, the flow of the cooling air is shut off and mixing of the ammonia gas and the air is prevented.
(Vi) The burner valve 53 is gradually closed and opened. At this time, the nitrogen filling the pipes 150 and the like in advance is released into the boiler in which the fuel is burning, and the insides of the pipes 130 and 150 of the ammonia gas fuel piping installation 3 are replaced with ammonia gas.
In addition, the ammonia outflow blocking valve 55 provided in the ammonia gas outflow pipe 151a confirms the pressure in the pipe, and appropriately opens to flow out the ammonia gas when the pressure becomes higher than a predetermined value.

(4) Operation for completing replacement of nitrogen gas with ammonia gas (step S4)
FIG. 6 is a view for explaining the operation at the completion of the operation of replacing the inside of the ammonia gas fuel piping installation 3 with nitrogen gas for the ammonia gas. The control unit 7 performs the following control from the state of FIG.
(I) Check the flow rate of nitrogen gas of 0.7 kg with the flow meter 50.
The capacity in the piping from the upstream end to the downstream end of the ammonia gas fuel piping installation 3 of the present embodiment is about 1 m ³ . 1 m ³ of nitrogen gas is about 0.7 kg. The fact that 0.7 kg of gas has passed through the flow meter 50 indicates that almost all of the nitrogen gas in the piping within the ammonia gas fuel piping installation 3 has flowed out and has been replaced with ammonia gas. Although not shown at an accurate scale in the drawing, the actual distance from the flow meter 50 to the downstream end of the ammonia gas fuel piping installation 3 is very small compared to the distance to the upstream end. Therefore, the volume in the pipe from the flow meter 50 to the downstream end of the ammonia gas fuel piping system 3 can be ignored.
(Ii) Close the burner valve 53 from the open state.
(Iii) The cooling air valve 61 is closed and opened. The burner valve 53 and the cooling air valve 61 can also be interlocked with each other. 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 shutoff valve 34 is closed from the open state.
In addition, the ammonia outflow blocking valve 55 provided in the ammonia gas outflow pipe 151a confirms the pressure in the pipe, and appropriately opens to flow out the ammonia gas when the pressure becomes higher than a predetermined value.

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

(6) Boost operation (step S6)
FIG. 7 is a view for explaining the pressure increase operation of the ammonia gas fuel piping installation 3. The control unit 7 performs the following control from the state of FIG.
(I) The pressure setting value of the pressure control valve 32 of the ammonia gas fuel piping installation 3 is changed from 0.15 MPa to 0.35 MPa.
(Ii) The pressure setting value of the vaporizer pressure control 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 control valve 12 in front of the vaporizer 20 is 0.45 MPa, which is larger than 0.35 MPa which is the pressure set value of the pressure control valve 32 of the ammonia gas fuel piping installation 3 It is because it is easy to control if there is a pressure gradient.

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

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

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

(10) Replacement Operation FIG. 11 shows the operation in the case where ammonia gas in the ammonia gas fuel piping installation 3 is replaced with nitrogen gas (step S10, YES), for example, when not using for a long period after stopping ammonia combustion. It is a figure explaining. The control unit 7 performs the following control from the state of FIG. 10 (step S11).
(I) The shutoff valve 31 is closed from the open state.
(Ii) The cooling air valve 61 is opened and closed.
(Iii) shut off the shutoff valve 54; (I), (ii), (iii), the ammonia outflow from the ammonia gas fuel piping installation 3 is prevented.
(Iv) The gas fuel pipe shutoff valve 71 is closed and opened. Thereby, BOG is sent to the gas burner 62A.
(V) Open the burner valve 53 from the closed state.
(Vi) Open the shutoff valve 34 from the closed state. The interior of the ammonia gas fuel piping system 3 is communicated by (v) and (vi).
(Vii) Open the ammonia outflow shutoff valve 55 from closed. Thereby, the flow path to ammonia gas absorption part 80 of ammonia is secured.
(Viii) The purge valve 36 of the purge pipe 133 is closed and opened to replace ammonia with nitrogen gas. Ammonia gas is sent from the ammonia gas outflow pipe 151 a to the ammonia gas absorbing 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 the ammonia gas detector, and the replacement is completed. In the case of step 4, the flow rate of 50 kg of nitrogen gas was confirmed by the flow meter 50, but in step S10, the flow meter is doubled. That is to completely replace ammonia gas with nitrogen gas.

As described above, the present embodiment has the following effects.
(1) The power generation facility 1 of the present embodiment includes a boiler 60 for burning fuel, a denitration facility 90 for decomposing nitrogen oxides contained in exhaust gas generated by combustion, and ammonia gas used in the denitration facility 90. Ammonia gas fuel piping equipment 3 which is branched from the ammonia gas supply equipment 2 to be supplied, the piping 130 connecting the ammonia gas supply equipment 2 and the denitrification equipment 90, and is connected to the boiler 60, ammonia gas fuel piping The ammonia gas outflow piping 151a which makes the ammonia gas in the installation 3 flow out to the ammonia gas absorption part 80 provided in the NOx removal equipment 90 is provided.
According to the present embodiment, the ammonia gas can be made to flow out of the ammonia gas fuel piping system 3 into the ammonia gas absorbing unit 80 provided in the ammonia gas supply facility 2, so that the ammonia gas can be discharged into the atmosphere. It can be prevented.
Further, since the ammonia gas is made to flow out to the ammonia gas absorbing unit 80 of the ammonia gas supply facility 2, the ammonia gas absorbing unit 80 can be shared, and no extra cost is incurred.

(2) The power generation facility 1 of the present embodiment is provided with a purge pipe 133 for introducing nitrogen gas as a purge gas to the ammonia gas fuel piping system 3.
According to the present embodiment, the ammonia gas present in the ammonia gas fuel piping system 3 can be sent to the ammonia gas absorbing unit 80 by purging the ammonia gas fuel piping system 3 with nitrogen gas, so ammonia gas fuel Disassembly inspection work etc. of the piping installation 3 can be performed.

(3) In the power generation facility 1 of this 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 in the case of flowing ammonia gas from the ammonia gas supply facility 2 to the ammonia gas fuel piping facility 3 is increased.
Thus, at the time of ammonia gas combustion, the pressure for sending ammonia gas can be increased, so that ammonia gas sufficient for combustion can be sent, and a sufficient injection pressure at the burner portion can be secured.

(4) In the power generation system 1 of the present embodiment, the ammonia gas fuel piping system 3 has the shutoff valves 31 and 54 on the upstream side and the downstream side, respectively. Ammonia gas can be sent to the ammonia gas absorbing unit 80 by closing the shutoff valves 31 and 54 and purging the piping system 3 for ammonia gas fuel with nitrogen gas, so that the ammonia gas flows out to the atmosphere. It is prevented.

(5) The power generation facility 1 of the present embodiment includes the gas burner 61E connected to the gas fuel pipe 170 that supplies gas fuel other than ammonia gas. Then, the ammonia gas fuel piping installation 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 connection portion 72 of the gas fuel pipe 170 to which the ammonia gas fuel pipe arrangement 3 is connected.
According to the present embodiment, the ammonia gas is prevented from flowing into the gas fuel pipe 170 upstream of the gas fuel pipe shut-off valve 71 by closing the gas fuel pipe shut-off valve 71.
Therefore, the deterioration and damage due to the corrosion of the gas fuel supply portion 70 and the upstream side of the gas fuel pipe shutoff valve 71 in the gas fuel pipe 170 due to ammonia are prevented.

(6) The power generation facility 1 of the present embodiment is a co-fired power generation facility equipped with a burner for burning fuel such as coal other than gas fuel. Therefore, various fuels can be burned.

(7) A power generation facility at a power plant, for example, a power generation facility for coal, includes an ammonia gas supply facility and a denitrification facility. Among such power generation facilities, there are cases where a gas burner for burning BOG or natural gas is provided, such as the gas burner 61E of the present embodiment.
According to the present embodiment, ammonia can be burned by adding the ammonia gas fuel piping installation 3 to such existing power generation equipment.

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

(9) In the present embodiment, since ammonia gas having a liquefaction temperature of about -33 degrees at atmospheric pressure can be used as a fuel, liquefaction and storage are relatively easy, and the liquefaction storage facility is compared to liquid hydrogen or LNG. It is cheap.

Reference Signs List 1 power generation facility 2 ammonia gas supply facility 3 piping system for ammonia gas fuel 6 boiler 7 control unit 10 storage tank 11 carburetor start valve 12 carburetor pressure control valve 13 carburetor bypass valve 20 carburetor 21 accumulator start valve 22 accumulator pressure adjustment Valve 23 Accumulator bypass valve 30 Accumulator 31, 33, 34, 52, 54 Cutoff valve 32 Pressure control valve 36 Purge valve 37 Gas supply for purge 40 Header 50 Flow meter 51 Flow control valve 53 Burner valve 55 Ammonia outflow cut off valve 60A Burner 61 Cooling air valve 62A Gas burner 70 Gas fuel supply unit 71 Gas fuel piping shut-off valve 72 1st connection unit 80 Ammonia gas absorption unit 90 Denitrification 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 NOx removal 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 denitrification facility;
A piping system for ammonia gas fuel branched from a pipe connecting the ammonia gas supply facility and the denitrification facility, and connected to the boiler;
Ammonia gas outflow piping for causing ammonia gas in the ammonia gas fuel piping facility to flow out to an ammonia gas absorbing unit provided in the ammonia gas supply facility;
Power generation equipment equipped with The ammonia gas fuel piping system includes a purge pipe for introducing a purge gas other than ammonia gas.
The power generation facility according to claim 1. A control unit that controls the operation of the power generation facility;
The control unit
Switching the destination of the ammonia gas supplied from the ammonia gas supply facility between the denitration facility or the ammonia gas fuel piping facility;
More than the pressure setting in the ammonia gas supply facility when ammonia gas flows from the ammonia gas supply facility to the denitrification 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 system has a shutoff valve on the upstream side and the downstream side, respectively.
The power generation facility according to any one of claims 1 to 3.

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