JP7305924B2 - steam generator - Google Patents

Description

The present invention relates to steam generation equipment.

Patent Literature 1 listed below discloses a combustion apparatus such as a boiler or a gas turbine that uses ammonia as fuel, and a power generation facility using the same (prior invention). This prior invention generates electricity by driving the steam turbine with steam generated by a heat recovery steam generator operated by the exhaust heat of the gas turbine, and uses the hot water generated by the heat recovery steam generator to generate electricity. vaporizes ammonia (liquid), which is the fuel of

WO2017/187619

By the way, in the above-described prior art, the liquid ammonia stored in the ammonia tank is heated by the heat recovery steam generator to be vaporized using the hot water generated, and the gas turbine is used to burn the gaseous ammonia as fuel. Vaporization requires a large amount of energy input.

SUMMARY OF THE INVENTION The present invention has been made in view of the circumstances described above, and an object of the present invention is to reduce the energy required for vaporizing liquid ammonia.

In order to achieve the above object, in the present invention, as a first solution related to steam generation equipment, a main body for generating steam by burning gaseous ammonia as a part of fuel, a tank for storing liquid ammonia, A means of providing a vaporizer for vaporizing liquid ammonia to generate the gaseous ammonia and a dehydration facility provided between the tank and the vaporizer for reducing the water content of the liquid ammonia is employed.

In the present invention, as a second solving means related to the steam generating equipment, the first solving means is further provided with regeneration equipment for regenerating the dehydration performance of the dehydration equipment.

In the present invention, as a third solution to the steam generation equipment, in the second solution, the regeneration equipment regenerates the dehydration performance by supplying the gaseous ammonia to the dehydration equipment as a regeneration gas. adopt the means of

In the present invention, as a fourth solution for the steam generation equipment, in the third solution, the regeneration equipment generates the regeneration gas by heating the gaseous ammonia. .

In the present invention, as a fifth solution to the problem, in the third or fourth solution, the regeneration gas discharged from the dehydration equipment is the gaseous ammonia supplied from the vaporizer to the main body. A means of supplying to the main body separately from is employed.

In the present invention, as a sixth solution to the steam generation equipment, in the second solution, the regeneration equipment regenerates the dehydration performance by supplying instrumentation air to the dehydration equipment as regeneration gas. adopt the means of

In the present invention, as a seventh solving means relating to the steam generating equipment, in any one of the first to sixth solving means, a means is adopted in which a plurality of the dehydration equipment are provided in parallel.

According to the present invention, as an eighth solving means related to the steam generating equipment, in any one of the first to seventh solving means, the main body adopts means for co-firing the pulverized coal with the gaseous ammonia.

According to the present invention, it is possible to reduce the energy required for vaporizing liquid ammonia as compared with the conventional method.

BRIEF DESCRIPTION OF THE DRAWINGS It is a system block diagram of the power generation equipment which concerns on 1st Embodiment of this invention. FIG. 2 is a system configuration diagram showing procedure 1 of reproduction processing in the first embodiment of the present invention; FIG. 4 is a system configuration diagram showing procedure 2 of reproduction processing in the first embodiment of the present invention; 3 is a system configuration diagram showing procedure 3 of reproduction processing in the first embodiment of the present invention; FIG. FIG. 4 is a system configuration diagram showing procedure 4 of reproduction processing in the first embodiment of the present invention; It is a system block diagram of the power generation equipment which concerns on 2nd Embodiment of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
The power generation facility according to the present embodiment is a facility that generates power using steam obtained by burning pulverized coal and ammonia. More specifically, gaseous ammonia obtained by vaporizing liquid ammonia (liquid ammonia) is co-fired with pulverized coal to generate power.

[First Embodiment]
First, the first embodiment will be described. As shown in FIG. 1, the power generation equipment according to the first embodiment includes a pulverized coal supply device 1, an ammonia supply device 2, a boiler 3 (main body), a steam turbine 4, a generator 5, a condenser 6, and a feed water pump 7. etc. The pulverized coal supply device 1, the ammonia supply device 2, and the boiler 3 (main body) in this power generation facility constitute the steam generation facility in the present invention.

In addition, the ammonia supply device 2 is the most characteristic component in this embodiment, and includes an ammonia tank 2a, a first pump 2b, a dehydration tower 2c (dehydration equipment), an ammonia vaporizer 2d, a second pump 2e, a regeneration It has a gas pipe 2f, a regeneration gas blower 2g and a heat exchanger 2h. Among these components, the regeneration gas pipe 2f, the regeneration gas blower 2g, and the heat exchanger 2h constitute regeneration equipment in the present invention.

The pulverized coal supply device 1 is a device that produces pulverized coal and supplies the pulverized coal to the boiler 3 as one fuel. This pulverized coal supply device 1 grinds coal in a mill to produce pulverized coal having a predetermined particle size, and supplies the pulverized coal to a boiler 3 sequentially and continuously.

The ammonia supply device 2 is a device that generates gaseous ammonia and supplies the gaseous ammonia to the boiler 3 as the other fuel. That is, the ammonia supply device 2 vaporizes liquid ammonia to generate gaseous ammonia, and sequentially and continuously supplies the gaseous ammonia to the boiler 3 . Here, the pulverized coal is the main fuel in the power generation facility, and gaseous ammonia is supplementary fuel supplied to the boiler 3 to the pulverized coal (main fuel).

In such an ammonia supply device 2, the ammonia tank 2a is a container with a predetermined capacity that temporarily stores liquid ammonia. The liquid ammonia contains a certain amount of water, and due to this water, the vaporization temperature is higher than that of pure liquid ammonia. The first pump 2b pumps out such liquid ammonia from the ammonia tank 2a and supplies it to the dehydration tower 2c.

The dehydration tower 2c is a facility for reducing water contained in liquid ammonia to a predetermined amount. The dehydration tower 2c contains a predetermined adsorbent inside, generates low-moisture ammonia by causing the adsorbent to adsorb moisture in the liquid ammonia flowing in from the input port p1, and outputs the low-moisture ammonia from the output port. Output from p2 toward the ammonia vaporizer 2d.

That is, the dehydration tower 2c is a dehydration facility provided between the ammonia tank 2a and the ammonia vaporizer 2d to reduce the water content of liquid ammonia. The low-moisture ammonia has a water content of, for example, 0.01 mol % or less and a vaporization temperature of about 5.degree. A moisture sensor for detecting the moisture content of the low-moisture ammonia is provided at the output port p2 of the dehydration tower 2c.

A plurality of dehydration towers 2c are provided in parallel as shown in the figure, and when the dehydration performance of the tower in operation is lowered, the operation is switched to another tower. Regarding the dehydration tower 2c whose dehydration performance has deteriorated, the dehydration performance is recovered by separately inputting regeneration gas (gaseous ammonia) from the first input/output port p3 or the second input/output port p4. That is, such a dehydration tower 2c is continuously operated while alternately repeating dehydration and regeneration.

The ammonia vaporizer 2d is a device that heats and vaporizes the low-moisture ammonia to generate gaseous ammonia. The ammonia vaporizer 2d heats the low-moisture ammonia to a vaporization temperature or higher by exchanging heat with seawater to generate gaseous ammonia and supplies the gaseous ammonia to the boiler 3 as fuel. The second pump 2e supplies seawater as a heat medium to the ammonia vaporizer 2d.

The regeneration gas pipe 2f is a pipe through which regeneration gas (gaseous ammonia) for regenerating the dehydration performance of the dehydration tower 2c flows. This regeneration gas pipe 2f takes in part of the gaseous ammonia supplied to the boiler 3 from the ammonia vaporizer 2d and supplies it to the ammonia tank 2a and the dehydration tower 2c. Although omitted in FIG. 1 due to space limitations, a plurality of on-off valves for setting the flow direction of the regeneration gas are provided at various locations on the regeneration gas pipe 2f.

The regeneration gas blower 2g is provided in the middle of the regeneration gas pipe 2f, and supplies the regeneration gas toward the ammonia tank 2a and the dehydration tower 2c. The operation timing of the regeneration gas blower 2g will be described later as an explanation of the operation.

The heat exchanger 2h is provided downstream of the regeneration gas blower 2g in the regeneration gas pipe 2f. The heat exchanger 2h heats or cools the regeneration gas by exchanging heat with water vapor, and supplies it to the ammonia tank 2a and the dehydration tower 2c.

The boiler 3 includes a furnace body for co-firing the above-described pulverized coal and gaseous ammonia, and generates steam by heating water flowing through hydrothermal tubes provided in the furnace body with combustion heat. In the above-mentioned furnace body, the lower part provided with a nozzle for injecting pulverized coal inside, a nozzle for injecting gaseous ammonia inside, a nozzle for supplying combustion air inside, etc. Space. Further, in the furnace body, the upper portion where a plurality of hydrothermal tubes are provided on the furnace wall or the like is a heat exchange area where combustion gas generated by combustion exchanges heat with water in the hydrothermal tubes. Such a boiler 3 corresponds to the main body in the present invention.

The steam turbine 4 is a rotary machine that rotates using steam supplied from the boiler 3 as a working fluid, and is axially coupled to the generator 5 . That is, the steam turbine 4 functions as a power source that drives the generator 5 to rotate.

The generator 5 is an electrical machine that generates AC power by being rotationally driven by the steam turbine 4 . The electric power generated by the generator 5 is supplied to consumers through predetermined distribution lines. The condenser 6 condenses the steam discharged from the steam turbine 4, that is, the steam (gas) after power recovery by the steam turbine 4, into condensed water. A water supply pump 7 supplies this condensed water to the boiler 3 . This condensed water is supplied to the hydrothermal tubes of the boiler 3 and becomes steam.

Next, the operation of such power generation equipment will be described in detail.
In this power generation facility, pulverized coal and gaseous ammonia are co-fired in the boiler 3 to generate high-temperature combustion gas, and the heat of the combustion gas is used to generate steam, which is the working fluid of the steam turbine 4 .

The kinetic energy of the steam causes the steam turbine 4 to generate rotational power, which in turn drives the generator 5 to generate power. The steam after power recovery by the steam turbine 4 is condensed into condensed water by the condenser 6 and is returned to the boiler 3 via the feed water pump 7 .

Here, the gaseous ammonia supplied to the boiler 3 as auxiliary fuel is produced by dehydrating liquid ammonia in the dehydration tower 2c and then heating it in the ammonia vaporizer 2d. That is, since the low-moisture ammonia supplied from the dehydration tower 2c to the ammonia vaporizer 2d has a water content of 0.01 mol% or less and a vaporization temperature of about 5°C, it is reliably vaporized by heat exchange with seawater. It becomes gaseous ammonia.

According to such power generation equipment, the vaporization temperature of the liquid ammonia can be lowered by providing the dehydration tower 2c. By comparison, it is possible to reduce the energy required to vaporize liquid ammonia.

Moreover, the regeneration equipment of the dehydration tower 2c starts to operate after a predetermined time has elapsed. Further, when the detected value of the moisture sensor provided in the dehydration tower 2c exceeds a predetermined threshold value, the regeneration equipment may start operating. When the regeneration facility starts operating, liquid ammonia is supplied to the dehydration tower 2c that is not in operation instead of the dehydration tower 2c that is in operation, and low-moisture ammonia is supplied from this dehydration tower 2c to the ammonia vaporizer 2c. Therefore, the supply of low-moisture ammonia from the dehydration tower 2c to the ammonia vaporizer 2c is continuously continued.

Then, for the dehydration tower 2c whose operation has been stopped due to a decrease in dehydration performance, the regeneration gas blower 2g starts operating and each on-off valve provided in the regeneration gas pipe 2f is operated to perform the following procedures 1 to 1. 4 performs dehydration performance recovery processing (regeneration processing).

That is, in procedure 1, as indicated by the dashed arrow in FIG. 2, the regeneration gas discharged from the regeneration gas blower 2g is supplied to the dehydration tower 2c from the second input/output port p4, thereby removing the liquid ammonia in the dehydration tower 2c. It is recovered in the ammonia tank 2a through the first input/output port p3 and the regeneration gas pipe 2f. Such a procedure 1 is a liquid removal process (liquid ammonia waste liquid process) in the dehydration tower 2c.

Subsequently, in step 2, as indicated by the dashed arrow in FIG. 3, the regeneration gas discharged from the regeneration gas blower 2g is supplied to the heat exchanger 2h and heated, and the heated regeneration gas is supplied to the first input/output port. By flowing into the dehydration tower 2c from p3, the water adhering to the adsorbent in the dehydration tower 2c is vaporized into steam, which is supplied to the boiler 3 from the second input/output port p4 together with the regeneration gas. Such procedure 2 is a regeneration process of the adsorbent in the dehydration tower 2c.

Here, the mixed gas of the regeneration gas and steam discharged from the second input/output port p4 is supplied to the boiler 3 through a system different from the gaseous ammonia output from the ammonia vaporizer 2c. That is, since the liquefying temperature of the water vapor is higher than that of gaseous ammonia, there is a risk of dew condensation on the inner wall of the pipe when mixed with gaseous ammonia. In order to prevent such condensation of water vapor, the mixed gas is supplied to the boiler 3 separately from the gaseous ammonia output from the ammonia vaporizer 2d.

Subsequently, in step 3, as indicated by the dashed arrow in FIG. 4, the regeneration gas discharged from the regeneration gas blower 2g is caused to flow into the dehydration tower 2c from the second input/output port p4 and to flow out from the first input/output port p4. and supplied to the boiler 3. That is, in procedure 3, the dehydration tower 2c is cooled by flowing the regeneration gas into the dehydration tower 2c that does not pass through the heat exchanger 2h. Such procedure 3 is a cooling process for the dehydration tower 2c.

Finally, in step 4, as indicated by the dashed arrow in FIG. 5, filling is performed by partially flowing the liquid ammonia discharged from the first pump into the dehydration tower 2c in which steps 1 to 3 have been completed. By this liquid filling process, the dehydration tower 2c, which has completed steps 1 to 3, is ready for the next operation. Such procedure 4 is a preparation process for restarting the dehydration tower 2c. It should be noted that in this procedure 4, the regeneration gas blower 2g has stopped operating.

According to such regeneration treatment of the dehydration tower 2c, continuous dehydration treatment of liquid ammonia can be realized, so that energy required for vaporization of liquid ammonia can be continuously reduced.

[Second embodiment]
Next, a second embodiment will be described. In the first embodiment, the dehydration tower 2c is regenerated using the regeneration gas, but in the second embodiment, instead of the regeneration gas, instrument air is used to regenerate the dehydration tower 2c, as shown in FIG. playback process. That is, the power generation facility according to the second embodiment includes an ammonia supply device 2A instead of the ammonia supply device 2, and the other components are the same as in the first embodiment.

The ammonia supply device 2A includes an ammonia tank 2a, a first pump 2b, a dehydration tower 2c, an ammonia vaporizer 2d, a second pump 2e, a regeneration gas pipe 2f and a heat exchanger 2h (first heat exchanger). 2 heat exchangers 2i. Among these components, the regeneration gas pipe 2f, the heat exchanger 2h and the second heat exchanger 2i constitute the regeneration facility in the present invention.

In the second embodiment, instrumentation air (compressed air) supplied from the outside is supplied to the regeneration gas pipe 2f. The second heat exchanger 2i uses seawater to cool the instrumentation air supplied to the boiler 3 from the second input/output port p4 of the dehydration tower 2c.

In such an ammonia supply apparatus 2A, gaseous ammonia is supplied to the boiler 3 in the same manner as the ammonia supply apparatus 2 of the first embodiment, but the dehydration tower 2c is regenerated by the following procedure.

That is, as the first procedure, instrumentation air taken in from the outside is supplied to the dehydration tower 2c from the second input/output port p4, so that the liquid ammonia in the dehydration tower 2c is removed from the first input/output port p3 and the regeneration gas pipe 2f. to the ammonia tank 2a via the

Then, as a second procedure, the instrumentation air is supplied to the heat exchanger 2h to be heated, and the heated instrumentation air is caused to flow into the dehydration tower 2c from the first input/output port p3, whereby the dehydration tower The water adhering to the adsorbent in 2c is vaporized into water vapor, which is supplied to the boiler 3 from the second input/output port p4 together with the instrumentation air.

Then, as a third procedure, instrumentation air is allowed to flow into the dehydration tower 2c from the second input/output port p4. That is, in the third procedure, the dehydration tower 2c is cooled by allowing instrumentation air that does not pass through the heat exchanger 2h to flow into the dehydration tower 2c. In the third procedure, the instrumentation air flowing out from the first input/output port p3 together with the dehydration tower 2c is cooled by the second heat exchanger 2i and then supplied to the boiler 3.

Finally, in the fourth step, the dehydration tower 2c for which the first to third steps have been completed is partially filled with the liquid ammonia discharged from the first pump. By this liquid filling process, the dehydration tower 2c, which has completed the first to third procedures, is ready for the next operation.

According to such regeneration treatment of the dehydration tower 2c, continuous dehydration treatment of liquid ammonia can be realized, so that energy required for vaporization of liquid ammonia can be continuously reduced.

It should be noted that the present invention is not limited to the above-described embodiments, and for example, the following modifications are conceivable.
(1) In the first and second embodiments, the present invention is applied to power generation equipment, which is an example of equipment that acquires energy by burning gaseous ammonia, that is, equipment that acquires electric power by burning gaseous ammonia. , the invention is not limited to this. The invention is also applicable to other energy harvesting installations.

The present invention is a facility for acquiring steam generated by a boiler 3 as thermal energy, that is, as shown in FIG. 2, from the system configuration of FIGS. It can be applied to a steam generating facility from which the water supply pump 7 is removed.

(2) In the first embodiment, the mixed gas generated in the regeneration process of the dehydration tower 2c is supplied to the boiler 3 separately from the gaseous ammonia output from the ammonia vaporizer 2d, but the present invention is not limited to this. . If condensation of water vapor is not a problem or if condensation can be ignored, the mixed gas and gaseous ammonia may be premixed and supplied to the boiler 3 .

(3) In the above-described second embodiment, the mixed gas of the steam generated in the regeneration process of the dehydration tower 2c and the instrumentation air is supplied to the boiler 3, but the present invention is not limited to this. Since this mixed gas does not contain components such as gaseous ammonia that affect the surrounding environment, it may be released to the atmosphere.

(4) In the first and second embodiments, pulverized coal and gaseous ammonia are co-fired in the boiler 3, but the present invention is not limited to this. Gaseous ammonia alone may be burned as the sole fuel. In addition, biomass fuel may be co-fired with gaseous ammonia instead of pulverized coal or in addition to pulverized coal, if necessary.

1 pulverized coal supply device 2, 2A ammonia supply device 2a ammonia tank 2b first pump 2c dehydration tower (dehydration equipment)
2d ammonia vaporizer 2e second pump 2f regeneration gas pipe (regeneration equipment)
2 g regeneration gas blower (regeneration equipment)
2h heat exchanger (regeneration equipment)
2i second heat exchanger (regeneration equipment)
3 Boiler (body)
4 steam turbine 5 generator 6 condenser 7 feed pump

Claims (8)

a body that burns gaseous ammonia as part of the fuel to generate steam;
a tank for storing liquid ammonia;
a vaporizer that vaporizes liquid ammonia by exchanging heat with seawater to produce the gaseous ammonia;
a dehydration facility provided between the tank and the vaporizer for reducing the water content of the liquid ammonia ;
a regeneration facility that regenerates the dehydration performance of the dehydration facility;
equipped with
The regeneration equipment regenerates the dehydration performance by supplying the gaseous ammonia to the dehydration equipment as regeneration gas,
The regeneration gas discharged from the dehydration equipment is supplied to the main body separately from the gaseous ammonia supplied to the main body from the vaporizer,
A steam generation facility characterized by : a body that burns gaseous ammonia as part of the fuel to generate steam;
a tank for storing liquid ammonia;
a vaporizer that vaporizes liquid ammonia by exchanging heat with seawater to produce the gaseous ammonia;
a dehydration facility provided between the tank and the vaporizer for reducing the water content of the liquid ammonia;
a regeneration facility that regenerates the dehydration performance of the dehydration facility;
with
The regeneration equipment regenerates dehydration performance by supplying instrumentation air as regeneration gas to the dehydration equipment.
A steam generating facility characterized by: 2. The steam generating facility according to claim 1 , wherein the regeneration facility generates the regeneration gas by heating the gaseous ammonia. The steam generation facility according to any one of claims 1 to 3, wherein a plurality of said dehydration facilities are provided in parallel. The steam generating facility according to any one of claims 1 to 4, wherein the main body co-fires the pulverized coal with the gaseous ammonia. a body that burns gaseous ammonia as part of the fuel to generate steam;
a tank for storing liquid ammonia;
a vaporizer for vaporizing liquid ammonia to produce the gaseous ammonia;
a dehydration facility provided between the tank and the vaporizer for reducing the water content of the liquid ammonia;
A regeneration facility that regenerates the dehydration performance of the dehydration facility,
The regeneration equipment regenerates dehydration performance by supplying the gaseous ammonia to the dehydration equipment as regeneration gas,
The steam generating equipment, wherein the regeneration gas discharged from the dehydration equipment is supplied to the main body separately from the gaseous ammonia supplied from the vaporizer to the main body. A body that burns gaseous ammonia as part of the fuel to generate steam, a tank that stores liquid ammonia,
a vaporizer for vaporizing liquid ammonia to produce the gaseous ammonia;
a dehydration facility provided between the tank and the vaporizer for reducing the water content of the liquid ammonia;
A regeneration facility that regenerates the dehydration performance of the dehydration facility,
The regeneration equipment regenerates dehydration performance by supplying the gaseous ammonia to the dehydration equipment as regeneration gas,
The regeneration equipment generates the regeneration gas by heating the gaseous ammonia,
The steam generating equipment, wherein the regeneration gas discharged from the dehydration equipment is supplied to the main body separately from the gaseous ammonia supplied from the vaporizer to the main body. a body that burns gaseous ammonia as part of the fuel to generate steam;
a tank for storing liquid ammonia;
a vaporizer for vaporizing liquid ammonia to produce the gaseous ammonia;
a dehydration facility provided between the tank and the vaporizer for reducing the water content of the liquid ammonia;
A regeneration facility that regenerates the dehydration performance of the dehydration facility,
The steam generating facility, wherein the regeneration facility regenerates dehydration performance by supplying instrumentation air as regeneration gas to the dehydration facility.

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