WO2019058563A1

WO2019058563A1 - Combustion apparatus and combustion method

Info

Publication number: WO2019058563A1
Application number: PCT/JP2017/034586
Authority: WO
Inventors: 博昭谷川; 泰孝和田; 優大内; 直彦谷口; 輝夫田中
Original assignee: 中国電力株式会社
Priority date: 2017-09-25
Filing date: 2017-09-25
Publication date: 2019-03-28
Also published as: JPWO2019058563A1; JP6296216B1

Abstract

Provided are a combustion apparatus and a combustion method with which it is possible to suppress, as much as possible, generation of nitrogen oxides and incomplete combustion of ammonia. This combustion apparatus 6A is able to co-combust pulverized coal and ammonia within a furnace. The combustion apparatus 6A is provided with a first nozzle 175 and one or more second nozzles 173B. The first nozzle 175 has a first jet orifice 175h through which pulverized coal is jetted out toward the interior of the furnace. The second nozzles 173B are disposed around the first nozzle 175. Each of the second nozzles 173B has a second jet orifice 173h through which ammonia is jetted out toward the interior of the furnace. The second jet orifices 173h of the second nozzles 173B are each opened in such a manner as to cause combustion flames of ammonia to be jetted in a direction tangential to a virtual circle centered on a central axis aligned with the jetting direction of combustion flame of the pulverized coal, and in such a manner as to be slanted toward the jetting direction side of the combustion flame of the pulverized coal.

Description

Combustion apparatus and combustion method

The present invention relates to a combustion apparatus and a combustion method. In particular, the present invention relates to a structure and a combustion method of a combustion apparatus suitable for power generation equipment such as a thermal power plant.

Thermal power plants etc. have installed a boiler as a power generation facility. The boiler generates high-temperature and high-pressure steam using the heat produced by burning a fossil fuel such as coal, natural gas, light oil, heavy oil, etc. 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). Therefore, LNG is used as fuel for thermal power plants. Gas fuels such as LNG need to be liquefied for convenience in transportation. Further, in the case of LNG, it is necessary to set the temperature to a low temperature of about -162 degrees in order to liquefy it, so liquefaction is not easy and there is a problem that the cost of low temperature storage equipment also increases.

From such a thing, utilization of ammonia gas is proposed as fuel which does not generate carbon dioxide (for example, refer to patent documents 1). Ammonia is liquefied at about -33 degrees, so it has the advantage of being easier to liquefy than, for example, LNG requiring about -162 degrees of liquefaction and requiring less expensive equipment.

Further, a multiple fuel burning combustion apparatus is disclosed which has a coaxial burner capable of co-firing mixed gas of natural gas and BOG (boil off gas) and pulverized coal inside the boiler (see, for example, Patent Document 2).

The coaxial burner according to Patent Document 2 comprises an inner pipe for injecting a pulverized coal flame into the interior of a boiler, and surrounding the inner pipe, the flame of a mixed gas of natural gas and BOG being coaxial with the injected direction of the pulverized coal flame. It consists of an outer pipe that jets in the direction.

JP, 2016-183840, A JP 2007-17030 A

However, when ammonia is burned, there is a concern that the nitrogen content contained in the ammonia component will be combined with oxygen to form nitrogen oxides.

Also, ammonia has a low burning rate, specifically, for example, where the burning rate of propane gas is 40 cm / s, the burning rate of ammonia is only 8 cm / s (therefore, when burning ammonia) Flames will be longer).

Therefore, in the case of co-firing ammonia with another fuel, for example, as disclosed in FIG. 3 and FIG. 4 of Patent Document 2, when injecting and burning horizontally coaxially using a coaxial burner, the other fuel Due to the delay of the ammonia flame with respect to the flame, the ammonia may be incompletely burned depending on the size and shape of the combustion space.

From such a thing, the combustion apparatus and the combustion method which can control generation | occurrence | production of nitrogen oxide and incomplete combustion of ammonia as much as possible are calculated | required. And, the above can be said to be the problem of the present invention.

The present invention has been made in view of such problems, and an object thereof is to provide a combustion apparatus and a combustion method capable of suppressing the generation of nitrogen oxides and the incomplete combustion of ammonia as much as possible.

The present inventors are a combustion apparatus for co-firing pulverized coal and ammonia inside a furnace, and a flame in which ammonia is burned is along the tangential direction of a virtual circle whose central axis is the injection direction of the combustion flame of pulverized coal. As described above, it is thought that the generation of nitrogen oxides and the incomplete combustion of ammonia can be suppressed as much as possible by tilting and injecting to the injection direction side of the combustion flame of pulverized coal, and based on this, the following new It came to invent various combustion devices and combustion methods.

(1) A combustion apparatus according to the present invention is a combustion apparatus for co-firing pulverized coal and ammonia inside a furnace, and a first nozzle having a first injection port for injecting pulverized coal toward the inside of the furnace; And one or more second nozzles disposed around the first nozzle and having a second injection port for injecting ammonia toward the inside of the furnace, wherein the second injection port of the second nozzle is The combustion flame of ammonia is inclined and opened in the injection direction side of the combustion flame of pulverized coal along the tangential direction of the imaginary circle whose central axis is the injection direction of the combustion flame of pulverized coal.

(2) In the combustion apparatus according to the present invention, an ammonia gas supply pipe for transporting ammonia toward the second nozzle and the first nozzle are disposed at a central portion, and the ammonia gas is distributed from the ammonia gas supply pipe A first gas ring, wherein the second nozzle comprises a plurality of second nozzles disposed around the first nozzle, wherein the second nozzles are configured to receive ammonia gas from the first gas ring It may be supplied.

(3) In the combustion apparatus according to the present invention, an ammonia gas supply pipe for transporting ammonia toward the second nozzle, a gas fuel pipe for transporting gas fuel, and the first nozzle are disposed at a central portion, A second gas ring to which gas fuel is distributed from a gas fuel pipe, a single second nozzle disposed around the first nozzle, and a second gas ring disposed around the first nozzle and directed toward the inside of the furnace And a burner nozzle connecting the second gas ring to the second nozzle and the third nozzle, wherein the burner nozzle connected to the second nozzle is A gas fuel piping shut-off valve capable of opening and closing the flow path of the burner nozzle is provided, and the ammonia gas supply piping can inject ammonia from the second injection port in a state where the gas fuel piping shut-off valve is closed. To, may be directly bonded to the burner nozzle connected to said second nozzle.

(4) The combustion method according to the present invention is a combustion method used in the combustion apparatus according to any one of (1) to (3), in which pulverized coal and ammonia are co-fired in the furnace, and the first nozzle The mixed combustion rate of ammonia, which is injected so as to be combustible from the second nozzle, is 0.8% or more with respect to pulverized coal which is injected so as to be combustible from the above.

The combustion apparatus according to the present invention is a combustion apparatus in which pulverized coal and ammonia are co-fired inside a furnace, and a flame in which ammonia is burned is a virtual circle whose central axis is the injection direction of the combustion flame in which pulverized coal is burned. Since the injection is performed along the tangential direction and inclined to the injection direction side of the combustion flame of pulverized coal, the combustion time of ammonia can be secured, and the incomplete combustion of ammonia can be suppressed as much as possible.

In the combustion method according to the present invention, the mixed combustion ratio of ammonia injected from the second nozzle to the combustible gas from the second nozzle is 0.8% or more with respect to pulverized coal injected from the first nozzle to the combustible gas, The occurrence of objects can be suppressed as much as possible.

It is a functional block diagram showing composition by one embodiment of a thermal power generation equipment provided with a combustion device by the present invention. It is a perspective view showing composition of a combustion device by a 1st embodiment of the present invention. It is the front view which expanded the 1st gas ring with which the combustion device by a 1st embodiment is provided. It is the longitudinal cross-sectional view which expanded the 1st nozzle with which the combustion apparatus by 1st Embodiment is equipped. It is the longitudinal cross-sectional view which expanded the front-end | tip part of the 1st nozzle with which the combustion apparatus by 1st Embodiment is equipped. It is an X arrow line view of FIG. It is an arrangement | positioning figure of several 2nd nozzle with which the combustion apparatus by 1st Embodiment is equipped, and is the state figure which looked at several 2nd nozzle from the furnace side. It is a perspective view which shows the structure of the combustion apparatus by 2nd Embodiment of this invention. It is the front view which expanded the 2nd gas ring with which the combustion device by a 2nd embodiment is equipped. It is a perspective view which shows the structure of the combustion apparatus by 3rd Embodiment of this invention. It is the front view which expanded the 3rd gas ring with which the combustion device by a 3rd embodiment is equipped. It is an arrangement | positioning figure of the 2nd nozzle and 4th nozzle with which the combustion apparatus by 3rd Embodiment is equipped, and is the state figure which looked at the 2nd nozzle and 4th nozzle from the furnace side. It is a graph which shows the time change of the amount of ammonia combustion used when carrying out the combustion test using the combustion apparatus by a 3rd embodiment. It is a figure which shows the time change of coal usage-amount used when carrying out the combustion test using the combustion apparatus by 3rd Embodiment, and FIG. 14 (a) is a graph which shows the time change of coal usage-amount per unit time Fig. 14 (b) is a table showing the time change of the amount of coal used per unit time, and Fig. 14 (c) is a table showing the time change of the average output of the power generation facility. It is a figure which shows the measurement point which measured the ammonia concentration of the exit of a combustion apparatus using the combustion apparatus by 3rd Embodiment. It is a figure which shows the time change of the NOx value of the exit of a combustion apparatus using the combustion apparatus by 3rd Embodiment, FIG. 16 (a) is a graph which shows the time change of a NOx value, FIG.16 (b) is. FIG. 16C is a table showing the time change of NOx value, and FIG. It is a figure which shows the time change of CO2 content in the exhaust gas discharged | emitted from a combustion apparatus using the combustion apparatus by 3rd Embodiment, and Fig.17 (a) is the ammonia injection amount per unit time, and CO2 content The graph which shows the time change of quantity, FIG.17 (b) is a table which shows the time change of the amount of ammonia injection per unit time, and CO2 content.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[Composition of thermal power plant]
First, a configuration according to an embodiment of a thermal power plant provided with a combustion apparatus according to the present invention will be described. FIG. 1 is a functional block diagram showing a configuration according to an embodiment of a thermal power plant equipped with a combustion apparatus according to the present invention.

Referring to FIG. 1, the thermal power generation facility 1 of one embodiment is a system capable of burning ammonia gas, but it is also possible to burn other than ammonia gas such as pulverized coal, oil, natural gas, or BOG.

Referring to FIG. 1, the thermal power generation facility 1 includes an ammonia gas supply facility 2 and an ammonia gas fuel piping facility 3. Further, the thermal power generation facility 1 includes a boiler (furnace) 6, a denitration facility 90, and a gas fuel supply unit 70. The gas fuel supply unit 70 can supply gas fuel other than ammonia gas to the boiler 6 via the gas fuel pipe 170. Furthermore, the thermal power generation facility 1 includes a control unit 7. The control unit 7 controls the whole of these devices.

(Composition of ammonia gas supply equipment)
Next, the configuration of the ammonia gas supply facility 2 according to the embodiment will be described. Referring to FIG. 1, the ammonia gas supply facility 2 includes a storage tank 10 and a vaporizer 20. Further, the ammonia gas supply facility 2 includes an accumulator 30 and an ammonia gas absorbing unit 80. In addition, the ammonia gas absorption part 80 is a water storage tank which stored water as a reality. The ammonia gas absorbing unit 80 can absorb the ammonia gas discharged from the blow valve 81 provided in the ammonia gas supply facility 2 into water.

(Configuration of storage tank)
Next, the configuration of the storage tank 10 according to the embodiment will be described. Referring to FIG. 1, the storage tank 10 stores pressurized and liquefied liquid ammonia. The storage tank 10 is connected to the vaporizer 20 through a pipe 110. The pipe 110 bifurcates in two directions on the way to the vaporizer 20. 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.

(Configuration of vaporizer)
Next, the configuration of the vaporizer 20 according to the embodiment will be described. Referring to FIG. 1, the vaporizer 20 heats and vaporizes liquid ammonia supplied from the storage tank 10. The liquid ammonia inside the vaporizer 20 can be heated and vaporized through the inside of the coiled pipe immersed in the hot water to generate ammonia gas. The downstream side of the vaporizer 20 is connected to the accumulator 30 via a pipe 120.

Referring to FIG. 1, the pipe 120 bifurcates in two directions on the way to the accumulator 30. An accumulator start valve 21 and an accumulator pressure control valve 22 for controlling the pressure in the accumulator 30 are sequentially arranged from the upstream side in one branched pipe 120a. An accumulator bypass valve 23 is disposed in the other branched pipe 120b.

(Structure of accumulator)
Next, the configuration of the accumulator 30 according to the embodiment will be described. Referring to FIG. 1, the accumulator 30 is a device that accumulates ammonia gas and stabilizes pressure. A pipe 130 extends from the downstream side of the accumulator 30. The pipe 130 branches 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.

(Structure of header)
Next, the configuration of the header 40 according to the embodiment will be described. Referring to FIG. 1, the header 40 has a pipe 140 connected downstream thereof. The pipe 140 is branched into a plurality of

NOx removal pipes

141, 142, and 143. These

denitration pipes

141, 142 and 143 are connected to the denitration equipment 90 via

denitration shutoff valves

41, 42 and 43.

(Configuration of NOx removal facility)
Next, the configuration of the NOx removal facility 90 according to the embodiment will be described. Referring to FIG. 1, the denitration equipment 90 is composed of three

denitration devices

91, 92, 93. The

NOx removal pipes

141, 142 and 143 are connected to the three

NOx removal devices

91, 92 and 93, respectively. The exhaust gas produced by combustion from the combustion device 6 is fed into the NOx removal piping 141, 142, 143, and ammonia gas introduced from the piping in which the NOx

removal shutoff valve

41, 42, 43 of 141, 142, 143 is opened. As a reducing agent, nitrogen oxides in exhaust gas can be converted to harmless nitrogen gas and water.

(Composition of piping system for ammonia gas fuel)
Next, the configuration of the ammonia gas fuel piping installation 3 according to the embodiment will be described. Referring to FIG. 1, the pipe 131 branched from the pipe 130 extending from the accumulator 30 is connected to the ammonia gas fuel pipe arrangement 3. The shutoff valve 31 is provided on the upstream side of the pipe 131. The purge pipe 133 is connected to the downstream side of the shutoff valve 31 via the purge valve 36. A purge gas supply unit 37 is connected to the end of the purge pipe 133. The purge gas supply unit 37 can flow a purge gas such as nitrogen gas into the ammonia gas fuel piping installation 3.

Referring to FIG. 1, the downstream side of the connecting 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 branched pipe 131a. The shutoff valve 33 is disposed in the other branched pipe 131 b. 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.

Referring to FIG. 1, the flow meter 50 measures the flow rate of gas flowing through the pipe 131. A pipe 150 extends from the downstream side of the flow meter 50. The piping 150 branches 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.

Referring to FIG. 1, the downstream side of the joined pipe 150 branches in two directions at 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 shutoff valve 55. As described above, the ammonia gas absorbing unit 80 is a water storage tank, and can dissolve ammonia gas in water.

Referring to FIG. 1, a burner valve 53 is disposed in the other branched ammonia gas supply pipe 151 b. On the downstream side of the burner valve 53 in the pipe 150, a cooling pipe 160 into which cooling air is introduced is connected via a cooling air valve 61. The ammonia gas outflow pipe 151 a may be branched downstream of the burner valve 53.

Referring to FIG. 1, 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 burner 62 A of the boiler 6 via the shutoff valve 54. ing.

(Configuration of gas fuel supply unit)
Next, the configuration of the gas fuel supply unit 70 according to the embodiment will be described. Referring to FIG. 1, 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 for transporting the BOG as a fuel to a burner described later.

Referring to FIG. 1, the gas fuel pipe 170 is connected to the burner of the combustion device 6 on the downstream side of the first connection portion 72. A gas fuel pipe shutoff valve 71 is disposed on the upstream side of the first connection portion 72 in the gas fuel pipe 170.

Referring to FIG. 1, BOG can be supplied to the burner 62A by closing the shutoff valve 54 and opening the gas fuel pipe shutoff valve 71. By opening the shutoff valve 54 and closing the gas fuel piping shutoff valve 71, ammonia can be supplied to the burner.

(Composition of a boiler)
Next, the configuration of the boiler 6 will be described. Referring to FIG. 1, the boiler 6 has a plurality of burners arranged in rows and columns. In the embodiment, the four

stage burners

62A, 62B, 62C, 62D are arranged in the height direction. Also, these burners are arranged in four rows in the horizontal direction.

Referring to FIG. 1, coal (dust coal) as a fuel is supplied from the coal storage unit 75 to the four-

stage burners

62A, 62B, 62C, and 62D. Gas fuel or ammonia can be supplied to the top four burners 62A.

Referring to FIG. 1, the combustion apparatus according to the present invention is, as a substance, four burners 62A disposed at the top of the boiler 6. And embodiment is different by supplying ammonia to all or one part of four top burners 62A. Hereinafter, the combustion apparatus according to the first embodiment is a combustion apparatus 6A, the combustion apparatus according to the second embodiment is a combustion apparatus 6B, and the combustion apparatus according to the third embodiment is a combustion apparatus 6C. explain.

First Embodiment
(Composition of combustion device)
Next, the configuration of the combustion apparatus according to the first embodiment will be described. The combustion apparatus according to the first embodiment does not include the gas fuel supply unit 70 disclosed in FIG. 1.

FIG. 2 is a perspective view showing the configuration of the combustion apparatus according to the first embodiment of the present invention. FIG. 3 is an enlarged front view of a gas ring provided in the combustion apparatus according to the first embodiment.

FIG. 4 is an enlarged vertical sectional view of a first nozzle provided in the combustion apparatus according to the first embodiment. FIG. 5 is an enlarged vertical cross-sectional view of the tip of the first nozzle provided in the combustion apparatus according to the first embodiment. 6 is a view on arrow X in FIG.

FIG. 7 is a layout view of the plurality of second nozzles provided in the combustion apparatus according to the first embodiment, and is a state diagram when viewing the plurality of second nozzles from the furnace side.

Referring to FIG. 2 or 3, the combustion apparatus 6A according to the first embodiment includes an arc-shaped first gas ring 171. The first gas ring 171 forms a cylindrical pipe member in an arc shape. The first gas ring 171 is partially interrupted. The first gas ring 171 closes its both ends. The first gas ring 171 is supplied with ammonia gas from an ammonia gas supply pipe 151 b.

Referring to FIG. 3 or 4, the first gas ring 171 has a long first nozzle 175 disposed at the center. Around the first nozzle 175, five long

second nozzles

173A, 173B, 173C, 173D and 173E are disposed. Since these

second nozzles

173A, 173B, 173C, 173D, and 173E are the same, the second nozzle 173B may be described as a representative.

Referring to FIG. 3 or 4, the first gas ring 171 projects five

burner nozzles

172A, 172B, 172C, 172D and 172E toward the center. These

burner nozzles

172A, 172B, 172C, 172D, 172E are connected to the

second nozzles

173A, 173B, 173C, 173D, 173E.

Referring to FIG. 3 or 4, when ammonia gas is supplied to the first gas ring 171, ammonia gas is supplied from the second injection port 173h provided at the tip of these

second nozzles

173A, 173B, 173C, 173D, 173E. Can be injected (see FIG. 5 or FIG. 6).

Thus, the combustion apparatus 6A according to the first embodiment supplies ammonia gas to the four first gas rings 171 disposed at the uppermost stage of the boiler 6, and the five second nozzles connected to the first gas rings 171 Ammonia gas can be injected from 173A, 173B, 173C, 173D and 173E. That is, ammonia gas can be injected from the one second nozzle 173B toward the inside of the furnace.

Referring to FIG. 3, the

burner nozzle

172A, 172B, 172C, 172D, 172E is provided with a gas fuel pipe shutoff valve 71B. By opening the gas fuel pipe cutoff valve 71B, ammonia gas can be injected from the second injection port 173h (see FIG. 5 or FIG. 6). By closing the gas fuel pipe shutoff valve 71B, it is possible to stop the injection of the ammonia gas from the second injection port 173h.

Referring to FIG. 4, the first nozzle 175 opens the first injection port 175 h at its tip. The first injection port 175 h can inject pulverized coal horizontally toward the inside of the furnace of the combustion device 6 A. Also, the first nozzle 175 holds the heavy fuel oil burner 174 inside. The heavy fuel oil burner 174 can inject misty heavy oil or diesel toward the inside of the furnace of the combustion apparatus 6A. The pulverized coal injected from the first nozzle 175 can be burned by igniting this heavy oil or light oil. Further, the ammonia gas injected from the second injection port 173 h can be mixedly burned.

Referring to FIG. 5, the second nozzle 173 B is disposed such that its axial direction is substantially parallel to the first nozzle 175. The second injection port 173 h of the second nozzle 173 B has a smaller inner diameter than the inner diameter of the second nozzle 173 B. Thereby, the ammonia gas flowing to the second nozzle 173B can be accelerated, and the ammonia gas can be injected from the second injection port 173h.

Further, referring to FIG. 5 or FIG. 6, the second injection port 173 h is in the flow direction C0 of ammonia gas flowing inside the second nozzle 173 B (that is, in the injection direction of pulverized coal injected from the first nozzle 175). The injection direction C of the ammonia gas is bent and injected with respect to the substantially parallel direction).

More specifically, referring to FIG. 5, the second injection port 173 h opens along a tangential direction B of a virtual circle whose central axis is the injection direction of the combustion flame of pulverized coal. Thus, the ammonia gas injected from the second injection port 173 h is injected along the tangential direction B of the imaginary circle whose central axis is the injection direction of the combustion flame of pulverized coal.
In the present specification, “along the tangential direction B” means that the injection direction C (the angle θ shown in FIG. 6) in which the ammonia gas is actually injected to the tangential direction B is about ± 30 degrees Represents a state that falls within the range of
Arrows A shown in FIGS. 6 and 7 indicate the direction from the second injection port 173 h toward the center of the first injection port 175 h.

Further, referring to FIG. 5, the injection direction C of the ammonia gas is inclined with respect to the tangential direction B at a predetermined angle α toward the injection direction side of the combustion flame of pulverized coal. In other words, when the second nozzle 173B is viewed from the front as shown in FIG. 6, the ammonia gas injection direction C follows the tangential direction B and at a predetermined angle α on the front side of the paper surface in FIG. It is inclined.
It is preferable to have an inclination angle α to the injection direction side of the combustion flame of pulverized coal in the injection direction C of ammonia gas.

Referring to FIG. 7, the combustion apparatus 6A burns the pulverized coal so that the flame in which the ammonia is burned is along the tangential direction B of the imaginary circle whose central axis is the injection direction of the combustion flame in which the pulverized coal is burned. Since the fuel is inclined and injected toward the flame injection direction, the combustion time of ammonia can be secured, and the incomplete combustion of ammonia can be suppressed as much as possible.

(Function of combustion device)
Next, the operation and effects of the combustion apparatus according to the first embodiment will be described.

Referring to FIGS. 2 to 7, the combustion apparatus 6A according to the first embodiment is a combustion apparatus 6A that co-fires pulverized coal and ammonia in the furnace, and the flame in which the ammonia is burned is a combustion flame of pulverized coal. Ammonia is injected from the

second nozzles

173A, 173B, 173C, 173D, and 173E along the tangential direction of the imaginary circle whose central axis is the injection direction, so incomplete combustion of ammonia can be minimized by the combustion flame of pulverized coal. , Can be suppressed.

Referring to FIG. 7, ammonia is injected from the

second nozzles

173A, 173B, 173C, 173D and 173E along the tangential direction of the combustion flame of pulverized coal, so a swirling flow is made around the combustion flame of pulverized coal. It is also possible to form.

As disclosed in FIG. 3 and FIG. 4 of Patent Document 2, when a coaxial burner is used to inject and burn horizontally coaxially, the ammonia flame is delayed with respect to other fuel flames, Depending on the size and shape of the combustion space, ammonia may be incompletely burned.

In the combustion apparatus 6A according to the first embodiment, the flame in which ammonia is burned is made to be along the tangential direction of a virtual circle whose center axis is the injection direction of the combustion flame of pulverized coal around the flame in which pulverized coal is burned. And, since the ammonia is injected by being inclined to the injection direction side of the combustion flame of the pulverized coal, the incomplete combustion of the ammonia can be suppressed as much as possible by securing the combustion time of the ammonia. In addition, although 6 A of combustion apparatuses by 1st Embodiment can suppress generation | occurrence | production of nitrogen oxide, the feasibility is demonstrated by 3rd Embodiment.

Second Embodiment
(Composition of combustion device)
Next, the configuration of the combustion apparatus according to the second embodiment will be described.

FIG. 8 is a perspective view showing the configuration of a combustion apparatus according to a second embodiment of the present invention. FIG. 9 is an enlarged front view of a gas ring provided in the combustion apparatus according to the second embodiment.

Referring to FIG. 8, the combustion device 6 B according to the second embodiment includes an arc-shaped second gas ring 178. Referring to FIG. 9, the second gas ring 178 has a long first nozzle 175 disposed at the center. A long second nozzle 173B is disposed around the first nozzle 175. In addition, long

third nozzles

178A, 178C, 178D, 178E are disposed around the first nozzle 175.

Referring to FIG. 9, the second gas ring 178 projects five

burner nozzles

172A, 172B, 172C, 172D and 172E toward the center. The burner nozzle 172B is connected to the second nozzle 173B. The burner nozzles 172A, 172C, 172D and 172E are connected to the

third nozzles

178A, 178C, 178D and 178E.

Referring to FIG. 9, the ammonia gas is supplied to the burner nozzle 172B from the ammonia gas supply pipe 151b. When the ammonia gas is supplied to the burner nozzle 172B, the ammonia gas can be injected from the second injection port 173h provided at the tip of the second nozzle 173B (see FIG. 5 or FIG. 6). And pulverized coal and ammonia can be co-fired inside the furnace.

As described above, the combustion apparatus 6B according to the second embodiment supplies ammonia gas to the burner nozzles 172B of the four second gas rings 178 disposed at the uppermost stage of the boiler 6, and one second nozzle connected to the burner nozzle 172B. Ammonia gas can be injected from 173B. That is, ammonia gas can be injected from the four second nozzles 173B toward the inside of the furnace.

Referring to FIG. 9, a gas fuel pipe shutoff valve 71B is provided on the upstream side of the connecting portion of the burner nozzle 172B with the ammonia gas supply pipe 151b.

Referring to FIG. 9, the second gas ring 178 connects the gas fuel pipe 170 (see FIG. 1). In the state where the gas fuel pipe shutoff valve 71B is closed, the gas fuel can be supplied to the

third nozzles

178A, 178C, 178D, 178E via the

burner nozzles

172A, 172C, 172D, 172E. And gas fuel can be injected toward the inside of a furnace from the tip part of

3rd nozzle

178A, 178C, 178D, and 178E, and gas fuel can be burned.

Referring to FIG. 9, in a state where the shutoff valve 54 is closed and the gas fuel pipe shutoff valve 71B is opened, the gaseous fuel can also be injected from the second nozzle 173B via the burner nozzle 172B. Thus, the combustion apparatus 6B according to the second embodiment can also burn gaseous fuel with the topmost burner 62A. In this case, it is preferable to burn the pulverized coal with the

burners

62B, 62C and 62D without co-firing the pulverized coal and the gas fuel inside the furnace with the topmost burner 62A.

With reference to FIGS. 2 to 9, the first gas ring 171 and the second gas ring 178 are structurally the same, but are distinguished by changing the sign because the flowing combustion is different. Similarly, although the second nozzle 173B and the

third nozzle

178A, 178C, 178D, 178E are structurally the same, they are distinguished by changing the sign because the flowing combustion is different.

Comparing FIG. 3 and FIG. 9, the combustion apparatus 6A according to the first embodiment injects ammonia gas from all the

first nozzles

173A, 173B, 173C, 173D and 173E, while according to the second embodiment. The difference is that the combustion device 6B can inject ammonia gas from the specific second nozzle 173B.

With reference to FIGS. 5 to 7, the combustion flame of ammonia injected from the second injection port 173 h follows the tangential direction of the imaginary circle whose central axis is the injection direction of the combustion flame of pulverized coal, and By opening the periphery of the injection hole 175 h at a predetermined inclination angle α, the combustion time of ammonia can be secured, and the ammonia can be completely burned.

Referring to FIG. 9, the second gas ring 178 may be connected to an air supply line (not shown) instead of the gas fuel pipe 170. In this case, referring to FIG. 7, air is injected from the

second nozzles

173A, 173B, 173C, 173D and 173E along the tangential direction of the combustion flame of pulverized coal, so the periphery of the combustion flame of pulverized coal It is also possible to form a swirling flow on the

Referring to FIG. 8, the ammonia gas injected from the burner nozzle 173B of the second gas ring 178 disposed at the right end (A) of the uppermost stage of the boiler 6 and the third from the right (C) swirls in the clockwise direction R On the other hand, the ammonia gas injected from the burner nozzle 178C of the second gas ring 178 disposed at the left end (D) of the uppermost stage of the boiler 6 and the third from the left (B) can swirl in the counterclockwise direction L. Also, this makes it possible to burn the ammonia gas uniformly without deviation.

(Function of combustion device)
Next, the operation and effects of the combustion apparatus according to the second embodiment will be described.

Referring to FIG. 8 or FIG. 9, in the combustion apparatus 6B according to the second embodiment, the flame in which the ammonia is burned is in the tangential direction B of the imaginary circle whose central axis is the injection direction of the combustion flame in which the pulverized coal is burned. Since the fuel is injected along the injection direction side of the combustion flame of pulverized coal at a predetermined angle α, the combustion time of the ammonia can be secured, and the incomplete combustion of the ammonia can be suppressed as much as possible.
Third Embodiment
(Composition of combustion device)
Next, the configuration of the combustion apparatus according to the third embodiment will be described.

FIG. 10 is a perspective view showing the configuration of a combustion apparatus according to a third embodiment of the present invention. FIG. 11 is an enlarged front view of a third gas ring provided in the combustion apparatus according to the third embodiment. FIG. 12 is a layout view of the second nozzle and the fourth nozzle provided in the combustion apparatus according to the third embodiment, in which the second nozzle and the fourth nozzle are viewed from the furnace side.

With reference to FIG. 10 or FIG. 11, the combustion apparatus 6C according to the third embodiment is disposed on the rightmost side of the topmost burner 62A. Then, in the left three rows of the uppermost stage burner 62A, a combustion device 6D to which ammonia gas is not supplied is disposed. While the combustion device 6C injects ammonia, the combustion device 6D can inject only gas fuel. The

combustion devices

6C and 6D include a third gas ring 179. Referring to FIG. 11, the third gas ring 179 has a long first nozzle 175 disposed at the center.

With reference to FIG. 10 or FIG. 11, the combustion device 6 C arranges a long second nozzle 173 B around the first nozzle 175. Further, the combustion device 6C has long

fourth nozzles

179A, 179C, 179D, 179E arranged around the first nozzle 175. The combustion device 6D has long

fourth nozzles

179A, 179B, 179C, 179D, 179E arranged around the first nozzle 175.

Referring to FIG. 11, the third gas ring 179 of the combustion device 6D protrudes five

burner nozzles

172A, 172B, 172C, 172D and 172E toward the central portion. The burner nozzle 172B is connected to the second nozzle 173B. The burner nozzles 172A, 172C, 172D, 172E are connected to the

fourth nozzles

179A, 179C, 179D, 179E.

Referring to FIG. 11, the ammonia gas is supplied to the second nozzle 173B from the ammonia gas supply pipe 151b. When the ammonia gas is supplied to the second nozzle 173B, the ammonia gas can be injected from the second injection port 173h provided at the tip of the second nozzle 173B (see FIG. 5 or FIG. 6). And pulverized coal and ammonia can be co-fired inside the furnace.

Thus, the combustion apparatus 6C according to the third embodiment supplies ammonia gas to the burner nozzle 172B of one third gas ring 179 disposed at the right end of the uppermost stage of the boiler 6, and connects one burner nozzle 172B to the burner nozzle 172B. The ammonia gas can be injected from the two nozzles 173B.

Referring to FIG. 12, the third gas ring 179 of the combustion apparatus 6C connects the gas fuel pipe 170 (see FIG. 1). In the state where the gas fuel piping shutoff valve 71B is closed, the gas fuel can be supplied to the

fourth nozzles

179A, 179C, 179D, 179E via the

burner nozzles

172A, 172C, 172D, 172E. And gas fuel can be injected toward the inside of a furnace from the tip part of the

4th nozzle

179A, 179C, 179D, and 179E, and gas fuel can be burned.

Referring to FIG. 11, a gas fuel pipe shutoff valve 71B is provided on the upstream side of the connecting portion of the burner nozzle 172B with the ammonia gas supply pipe 151b.

Referring to FIG. 11, in the state where the shutoff valve 54 is closed and the gas fuel pipe shutoff valve 71B is opened, gaseous fuel can also be injected from the second nozzle 173B via the burner nozzle 172B. Thus, the combustion apparatus 6C according to the third embodiment can also burn gaseous fuel. In this case, it is preferable to burn the pulverized coal with the

burners

62A, 62B, 62C and 62D without co-firing the pulverized coal and the gas fuel inside the furnace with the combustion apparatus 6C.

With reference to FIGS. 2 to 11, the first gas ring 171 and the third gas ring 179 are structurally the same, but are distinguished by changing the sign because the flowing combustion is different. Similarly, although the second nozzle 173B and the

fourth nozzle

179A, 179B, 179C, 179D, 179E are structurally the same, they are distinguished by changing the sign because the circulating combustion is different.

Referring to FIG. 11, the ammonia gas supply pipe 151 b is provided with a shutoff valve 54. A return pipe 176 branches off upstream of the shutoff valve 54. In the return pipe 176. A shutoff valve 177 is provided. The return pipe 176 is a pipe used when the ammonia gas is not supplied to the burner nozzle 172B from the ammonia gas supply pipe 151b. When the return gas is not supplied, the shutoff valve 54 is closed and the shutoff valve 177 is opened.

Referring to FIG. 11, when the ammonia gas is supplied to the burner nozzle 172B, the shutoff valve 54 is opened, and the gas fuel pipe shutoff valve 71B and the shutoff valve 177 are closed.

When FIG.8, FIG.9, and FIG.10 are contrasted, the combustion apparatus 6B by 2nd Embodiment injects ammonia gas from the 2nd nozzle 173B of all the 2nd gas rings 178, but 3rd implementation The combustion apparatus 6C according to the embodiment has a difference that the ammonia gas is injected from the second nozzle 173B of the specific third gas ring 179.

Comparing FIG. 8 and FIG. 10, the combustion apparatus 6B and the combustion apparatus 6C are the same, and the second embodiment arranges the four combustion apparatuses 6B, while the third embodiment performs the combustion. There is a difference that only one device 6B is arranged.

With reference to FIGS. 5 to 7, the combustion device 6C is arranged such that the flame in which ammonia is burned is along the tangential direction B of a virtual circle whose central axis is the injection direction of the combustion flame in which pulverized coal is burned and Since the injection is performed with the predetermined angle α inclined to the injection direction side of the combustion flame of pulverized coal, the combustion time of ammonia can be secured, and the incomplete combustion of ammonia can be suppressed as much as possible.

Referring to FIG. 11, the third gas ring 179 may be connected to an air supply line (not shown) instead of the gas fuel pipe 170. In this case, if FIG. 7 is used, air is injected from the

fourth nozzles

179A, 179C, 179D, 179E along the tangential direction of the combustion flame of pulverized coal, so the swirling flow around the combustion flame of pulverized coal It is also possible to form

(Function of combustion device)
Next, the operation and effects of the combustion apparatus according to the third embodiment will be described.

Referring to FIGS. 10 to 12, a combustion apparatus 6C according to the third embodiment is a combustion apparatus 6C for co-firing pulverized coal and ammonia inside a furnace, and a flame in which ammonia is burned causes the pulverized coal to be burned. The ammonia is injected at a predetermined angle α to the injection direction side of the combustion flame of the pulverized coal so that the periphery of the flame is along the tangential direction of the imaginary circle whose central axis is the injection direction of the combustion flame of the pulverized coal Therefore, the incomplete combustion of ammonia can be suppressed as much as possible by securing the combustion time of ammonia.

Referring to FIG. 12, the shutoff valve 54 provided in the ammonia gas supply pipe 151 b is opened, and ammonia is closed by closing the gas fuel pipe shutoff valve 71 B provided in the burner nozzle 172 B and the shutoff valve 177 provided in the return pipe 176. The gas is supplied to the second nozzle 173B via the ammonia gas supply pipe 151b → the first connection portion 72 → the burner nozzle 172B. Furthermore, when the cross section perpendicular to the length direction of the pulverized coal flame injected from the first nozzle 175 is approximated to a circle, as shown by the arrow in FIG. 12, the second injection port 173h of the second nozzle 173B is , Ammonia is injected in the tangential direction of this circle.

Referring to FIG. 12, the ammonia is placed along the tangential direction of the imaginary circle centered on the injection direction of the combustion flame of the pulverized coal around the periphery of the pulverized coal flame and on the injection direction side of the combustion flame of the pulverized coal Since ammonia is injected at a predetermined angle α, the combustion distance of ammonia is increased, whereby the combustion time of ammonia can be secured and the ammonia can be completely burned.

[Combustion test]
Next, the result of the combustion test using the combustion apparatus 6C according to the third embodiment will be described. FIG. 13 is a graph showing the time-dependent change of the ammonia combustion amount used when the combustion test was performed using the combustion apparatus according to the third embodiment.

FIG. 14 is a diagram showing the time change of the amount of used coal when the combustion test was performed using the combustion apparatus according to the third embodiment, and FIG. 14 (a) is a timing of the used amount of coal per unit time The graph which shows change, FIG.14 (b) is a table | surface which shows the time change of the amount of coal consumption per unit time, FIG.14 (c) is a table | surface which shows the time change of the average output of power generation equipment.

FIG. 15 is a view showing measurement points at which the ammonia concentration at the outlet of the combustion apparatus is measured using the combustion apparatus according to the third embodiment.

FIG. 16 is a diagram showing the time change of the NOx value at the outlet of the combustion device using the combustion device according to the third embodiment, and FIG. 16 (a) is a graph showing the time change of the NOx value; b) is a table showing the time change of the NOx value, and FIG. 16 (c) is a table showing the time change of the average output of the power generation facility.

FIG. 17 is a diagram showing the time change of the CO 2 content in the exhaust gas discharged from the combustion apparatus using the combustion apparatus according to the third embodiment, and FIG. 17 (a) is an ammonia injection per unit time The graph which shows the time change of quantity and CO2 content, FIG.17 (b) is a table which shows the time change of the amount of ammonia injection per unit time, and CO2 content.

In the thermal power generation facility 1 disclosed in FIG. 1, the following combustion test was performed by ammonia mixed combustion.

As shown in FIG. 13, the test period is 7 days, from 13 o'clock to 17 o'clock on the first day, 10 o'clock to 17 o'clock on the second day to the 6th day, and 10 o'clock to 13 o'clock on the 7th day In the above, a maximum of 450 kg / h of ammonia (note that this is the maximum flow rate of the vaporizer 20 and corresponds to 400 kg of coal) was used.

More specifically, 100 kg / h of ammonia is burned from 13 o'clock to 15 o'clock on the first day, and 200 kg / h of ammonia is burned from 15 o'clock to 16 o'clock on the first day. From the hour to 17: 00, 400 kg / h of ammonia was burned, and from the second day on, 450 kg / h of ammonia was burned.

Also, basically, since the boiler was operated at a load of 155 MW, the mixed combustion rate of ammonia was about 0.6% (equivalent to 1 MW), but only on the fifth day, the boiler was operated at a load of 120 MW The mixed combustion rate of ammonia was about 0.8%. In addition, ammonia was burned in the range where there is no excess of exhaust gas.

In addition, liquid ammonia used for combustion has a purity of 99.98%, water content of 0.016%, and an oil content of less than 1.0 ppm, and coal species co-fired with ammonia is 60% for mount oren, and Bocabri premium Is 40%.

(Boiler metal temperature)
Referring to FIG. 15, the temperature of metal parts such as piping provided in the boiler 6, that is, the boiler metal temperature was measured at the time of coal-only combustion and at the time of mixed combustion of ammonia and coal. There are six measurement points: a primary superheater outlet, a reheater outlet, a secondary superheater inlet, a secondary superheater middle, and a secondary superheater outlet.

Referring to FIG. 15, as a result of measurement, when the load of the boiler is 155 MW, the boiler metal temperature at the primary superheater outlet is 400 to 450 ° C., and the boiler metal temperature at the reheater outlet is 500 to 550 ° C. The boiler metal temperature at the secondary superheater inlet is 400 to 450 ° C, the boiler metal temperature at the middle of the secondary superheater is 450 to 500 ° C, and the boiler metal temperature at the secondary superheater outlet is 500 to 600 ° C. And, there was almost no change at the time of co-firing of ammonia and coal.

Similarly, when the load on the boiler is 120 MW, the boiler metal temperature at the primary superheater outlet is 400 to 450 ° C, the boiler metal temperature at the reheater outlet is 500 to 600 ° C, and the boiler metal at the secondary superheater inlet The temperature is 400 to 450 ° C, the boiler metal temperature in the middle of the secondary superheater is 450 to 550 ° C, and the boiler metal temperature at the outlet of the secondary superheater is 500 to 600 ° C. And there was almost no change.

That is, in the temperature distribution in the boiler 6, the effect of co-firing ammonia with coal was hardly observed.

(Coal amount evaluation)
FIG. 14 shows the amount of coal used per hour before and after mixed combustion, and the difference between the amounts of coal used. The table in FIG. 14 (b) shows the numerical values used in the graph of (a) in the form of a table, and the table in FIG. 14 (c) Indicates the average value of

Referring to FIG. 14, the reduction in the amount of used coal after mixed firing compared with that before mixed firing was 0.50 T / h on average for 7 days. That is, 450 kg / h of the amount of ammonia combustion became almost the same as 500 kg / h (anhydrous) of the amount of reduction of coal. Also, comparing the 1st to 7th days, the amount of reduction of coal on the 5th day became the maximum value of 1.96T / h. As mentioned above, the coal type of coal used for the combustion is 60% of Mount Oen and 40% of Boca-Bri Premium.

(Boiler outlet NOx value)
Referring to FIG. 15, as indicated by crosses in the sectional views shown by [system A] and [system B], ECO (at a total of 48 points of system A 24 points and system B 24 points at the boiler outlet) The economizer) NOx value of the outlet gas was measured.

FIG. 16 shows NOx values at the boiler outlet before and after mixed combustion. In addition, since adjustment of various devices was performed on the 1st day and the NOx meter was checked on the 3rd day, it is excluded from the data. The table of FIG. 16 (b) shows the numerical values used in the graph of FIG. 16 (a) in the form of a table, and the table of FIG. 16 (c) shows the power plant output, mixed combustion rate, and FIG. 16 (c) The average value of the day difference shown in the leftmost column of Further, the value before mixed combustion is a value 30 minutes before the injection of ammonia, and the value after mixed combustion is an average value of data of 4 to 5 points taken every 30 minutes after the injection of ammonia.

Referring to FIG. 16 (c), on the fifth day when the mixed combustion rate of ammonia is about 0.8%, the mixed combustion rate of ammonia is about 0.6% to about 0.8 as compared to other days. It was confirmed that the NOx value at the boiler outlet after co-firing decreased significantly as compared to before co-firing, contrary to the increase to%.

Further, referring to FIG. 16 (c), on the second, fourth, sixth and seventh days, the mixed burning rate of ammonia was about 0.6%, compared to the mixed burning before mixed burning. While the increase in NOx value after that was not stable, the average value showed a positive value of 0.17 ppm, while the mixed combustion rate of ammonia was about 0.8% on the 5th, before mixed combustion It was confirmed that the amount of increase in NOx value after mixed combustion compared to the above became a negative value of -13.75 ppm.

Thus, when ammonia is co-fired with coal, the ammonia co-firing rate is desirably 0.8% or more, and it has been suggested that the NOx value can be reduced as the ammonia supply amount is increased.
this is,
4NO + 4 NH 3 + O 2 → 4 N 2 + 6 H 2 O
It is presumed that the noncatalytic denitrification reaction has progressed as shown in the chemical reaction formula.

(Boiler outlet ammonia concentration)
Referring to FIG. 15, when the ammonia concentration of ECO (coal economizer) outlet gas was measured at a total of 10 points at the boiler outlet, the ammonia concentration before ammonia injection into the fuel was 0.3 ppm, and the ammonia into the fuel was The ammonia concentration after injection was 0.1 to 0.4 ppm. That is, even after the ammonia injection into the fuel, almost no ammonia remained at the boiler outlet, and it was confirmed that the ammonia was completely burned.

This is because ammonia is injected in the tangential direction of the pulverized coal flame so that the ammonia draws a spiral locus around the pulverized coal flame, and the combustion time of the ammonia is secured by taking a long combustion distance of the ammonia. It is estimated that

(CO2 analysis)
Referring to FIG. 15, the composition of the exhaust gas from the boiler was measured at the two outlet points of the boiler. FIG. 17 shows the output of the boiler, the amount of injected ammonia, and the amount of CO 2 in the exhaust gas from the boiler. The table of (b) shows the numerical values used in the graph of (a) in the form of a table.

Referring to FIG. 17, when the initial CO 2 amount is 12.8%, the mixed combustion rate of ammonia is 0.6% to 0.8%, so the CO 2 amount is the product of those numerical values, 0. It was predicted to decrease by as little as 1%, but in practice it decreased by 0.2 to 1.3%.

Also, the annual carbon dioxide reduction amount when the mixed combustion rate is about 0.6% is about 3.99 (thousand t-CO 2 / year), and the annual carbon dioxide reduction when the mixed combustion rate is about 0.8% The amount was about 4.12 (thousand t-CO 2 / year). (In calculation, the carbon dioxide emission factor was calculated using the emission factor by electric power company in FY2015 (China Electric Power: 0.0007t-CO2 / kWh) and the facility operation rate as 70%.) It is considered that carbon dioxide emissions can be reduced according to the rate of mixed combustion, since all mixed ammonia could be burned in the boiler.

As described above, the present embodiment has the following effects.
(1) The combustion apparatus according to the present invention is a combustion apparatus for co-firing pulverized coal and ammonia inside a furnace, and a flame in which ammonia is burned burns pulverized coal around a flame in which pulverized coal is burned. Ammonia is injected by tilting to the injection direction side of the combustion flame of pulverized coal so as to be along the tangential direction of a virtual circle whose central axis is the injection direction, so by securing the combustion time of ammonia, incompleteness of ammonia Combustion can be suppressed as much as possible.

According to the present embodiment, the ammonia is injected in the tangential direction around the pulverized coal flame, and the combustion distance of the ammonia is increased, whereby the combustion time of the ammonia is secured and the ammonia is completely burned.

(2) In the combustion method according to the present invention, the mixed combustion ratio of ammonia injected from the second nozzle to the combustible from the second nozzle is 0.8% or more with respect to pulverized coal injected to the combustion from the first nozzle. And the generation of nitrogen oxides can be suppressed as much as possible.

According to the present embodiment, the ammonia used for the combustion simultaneously has an effect of denitrifying NOx in the exhaust gas generated by the combustion, so that the ammonia can be effectively used.

1 Thermal power generation facility 2 Ammonia gas supply facility 3 Ammonia gas fuel piping facility 6 Boiler (fire furnace)
6A, 6B, 6C, 6D burner (combustion device)
DESCRIPTION OF SYMBOLS 7 control part 10 storage tank 11 vaporizer start valve 12 vaporizer pressure control valve 13 vaporizer bypass valve 20 vaporizer 21 accumulator start valve 22 accumulator pressure control valve 23 accumulator bypass valve 30

accumulator

31, 33, 34, 52, 54 interruption | blocking Valve 32 Pressure adjusting valve 36 Purge valve 37 Gas supply for purging 40 Header 50 Flow meter 51 Flow adjusting valve 53 Burner valve 54 Shutoff valve 55 Ammonia outflow cut off valve 60A Burner 61 Cooling air valve 62

Burner

62A, 62B, 62C, 62D Gas burner 70 Gas

fuel supply unit

71, 71B Gas fuel piping shut-off valve 72 First connection unit 80 Ammonia gas absorption unit 90

Denitrification equipment

110, 110a, 110b, 120, 120a, 120b, 130, 131, 131a, 131b, 132, 1 0, 150, 150a, 150b Piping 133 Purge piping 151a Ammonia gas outflow piping 151b Ammonia supply piping 160 Cooling piping 170 Gas fuel piping 171

1st gas ring

172, 172A, 172B, 172C, 172D, 172E Burner nozzle 173A to 173E 2nd nozzle 173h 2nd injection port 174 heavy fuel oil burner 175 1st nozzle 175h 1st injection port 176 return piping 177 shutoff valve 178

2nd gas ring

178A, 178C, 178D, 178E 3rd nozzle 179

3rd gas ring

179A, 179B, 179C. 179D · 179E fourth nozzle

Claims

A combustion apparatus for co-firing pulverized coal and ammonia inside a furnace,
A first nozzle having a first injection port for injecting pulverized coal toward the inside of the furnace;
One or more second nozzles disposed around the first nozzle and having a second injection port for injecting ammonia toward the inside of the furnace;
In the second injection port of the second nozzle, the combustion flame of ammonia is along the tangential direction of a virtual circle whose central axis is the injection direction of the combustion flame of pulverized coal, and the injection direction side of the combustion flame of pulverized coal The burner is inclined and open.
Ammonia gas supply piping for transporting ammonia toward the second nozzle;
And a first gas ring disposed at a central portion of the first nozzle, the ammonia gas being distributed from the ammonia gas supply pipe,
The second nozzle comprises a plurality of second nozzles disposed around the first nozzle,
The combustion apparatus according to claim 1, wherein ammonia gas is supplied from the first gas ring to the second nozzles.
Ammonia gas supply piping for transporting ammonia toward the second nozzle;
Gas fuel piping to which gas fuel is transported;
A second gas ring in which the first nozzle is disposed at the center and the gas fuel is distributed from the gas fuel pipe;
A single second nozzle disposed around the first nozzle;
One or more third nozzles disposed around the first nozzle and injecting gas fuel toward the inside of the furnace;
And a burner nozzle connecting the second gas ring and the second and third nozzles.
The burner nozzle to which the second nozzle is connected has a gas fuel pipe shutoff valve capable of opening and closing the flow path of the burner nozzle.
The ammonia gas supply pipe according to claim 1, wherein the ammonia gas supply pipe is directly connected to a burner nozzle connected to the second nozzle so as to be capable of injecting ammonia from the second injection port in a state where the gas fuel pipe shutoff valve is closed. Combustion equipment.
It is a combustion method which is used for the combustion device according to any one of claims 1 to 3 and which co-fires pulverized coal and ammonia inside a furnace,
A combustion method, wherein a mixed combustion rate of ammonia injected from the second nozzle to be combustible from the second nozzle is 0.8% or more with respect to pulverized coal to be combusted from the first nozzle.