JP2002195051A - Steam injection gas turbine generator set - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a steam injection gas turbine generator set capable of recovering heart energy of gas turbine waste heat to the maximum, even if necessary power quantity fluctuates, reducing the necessary fuel gas quantity and enhancing the heat efficiency. SOLUTION: This steam injection gas turbine power generator set is provided with a gas turbine power generator 12, comprising a compressor 12a, combustor 12b, turbine 12c, and generator 11, waste heat recovery boiler 14 generating steam by the waste heat of the turbine, mixing device 16 for mixing fuel gas with the steam, reformer 18 positioned between the gas turbine power generator and the waste heat recovery boiler and reforming fuel gas into reformed gas, including hydrogen, reformed gas storage device 20 for storing the reformed gas, and a reformed gas quantity adjuster 21 for adjusting the reformed gas quantity to be fed from the reformed gas storage device to the combustor.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas turbine power generator for generating power and generating steam, and more particularly to a steam injection gas turbine power generator for injecting steam into a gas turbine.

[0002]

2. Description of the Related Art A two-fluid cycle gas turbine for injecting steam into a gas turbine is disclosed in, for example, Japanese Patent Publication No. Sho 54-3.
No. 4865, "Two Working Fluid Heat Engine" is known. This two-fluid cycle gas turbine (hereinafter referred to as a chain cycle from the inventor's name) includes a throttle valve 51, a compressor 52, and a combustion chamber 5 as illustrated in FIG.
3. It is composed of a water treatment device 54, a pump 55, a heat exchanger 56, turbines 57, 58, a condenser 59, etc.
The air sucked from the atmosphere is compressed by a compressor 52 and supplied to a combustion chamber 53. The compressed air burns fuel to generate high-temperature combustion gas. The combustion gas drives turbines 57 and 58 to generate a compressor. 52 and the load, and the heat exchanger 5
The steam is generated at 6, and the moisture is collected at the condenser 59 and released to the atmosphere. In the chain cycle, the steam S generated in the heat exchanger 56 is injected into the combustion chamber 53, so that the flow rate of the combustion gas flowing into the turbine increases, and the specific heat of the combustion gas increases. It has the characteristic that can increase.

The inventor of the present invention has filed and applied for Japanese Patent Publication No. 8-26780 as a two-fluid cycle gas turbine having an improved chain cycle.

As shown in FIG. 3, a "partially regenerating two-fluid gas turbine" disclosed in Japanese Patent Publication No. Hei 8-26780 has a compressor 52 for compressing air and a combustor 5 for burning fuel.
3, a gas turbine comprising a turbine 57 driven by combustion gas and driving a compressor, a mixer 60 for increasing the pressure of compressed air using steam S (saturated steam) as a driving source and mixing both fluids, and a turbine 57 , A superheater 56 provided downstream of the superheater 56 for heating the mixed gas by the turbine exhaust, a waste heat boiler 62 provided downstream of the superheater 56 for evaporating water using the turbine exhaust as a heat source, and a compressor 52. An air line 63 for guiding a part of the compressed air by the exhaust gas to the combustor 53 and a remainder to the mixer 60; a main steam line 64 for sending a part of the steam S from the exhaust heat boiler 62 to the mixer; And a mixed gas line 65 for guiding the mixed gas by the superheater 56 to the combustor 53.

In this partially regenerating two-fluid gas turbine,
Since a part of the compressed air is sucked and mixed with the steam S generated by collecting the exhaust heat of the gas turbine, and the exhaust heat of the gas turbine is further recovered by the superheater 56 and then injected into the combustor, As much as the air whose temperature has been increased by the exhaust heat recovery of the gas turbine, more energy can be recovered than in the chain cycle, and the cycle efficiency can be improved.

FIGS. 4 and 5 are heat recovery diagrams of the above-described chain cycle and two-fluid gas turbine. In these figures, the horizontal axis represents the exchanged heat quantity based on the gas turbine exhaust gas, and the vertical axis represents the temperature. The abscissa specifically corresponds to the enthalpy of gas turbine exhaust gas based on 0 ° C. In these figures, the gas turbine exhaust gas
The water is cooled from about 550 ° C. to about 150, and the heat is used to heat the water to the saturation temperature, evaporate at the saturation temperature into saturated steam, and further heat to superheated steam.

The heat recovery after the evaporation is heating of only steam in the chain cycle of FIG. 4, while heating of a mixed gas of steam and air is performed in the partially regenerating two-fluid gas turbine of FIG. Therefore, in FIG. 5, the temperature rises due to the mixing of the compressed air, and the flow rate of the mixed gas further increases, so that the temperature rise gradient becomes gentle. As a result, the recovery of the effective energy corresponding to the shaded region in FIG. 5 is larger than in the chain cycle, and the cycle efficiency is improved accordingly. As a result, in this example, the generator end efficiency is changed from 41.10% to 4%.
It has risen to 1.18%.

[0008]

In the above-described conventional gas turbine power generator, when the required power generation amount is reduced, the gas turbine turbine inlet temperature must be reduced to a partial load operation. There was a problem that efficient operation could not be performed.

The present invention has been made in order to solve such a problem. That is, an object of the present invention is to enable high-efficiency operation with an increased turbine inlet temperature even when the required power generation amount is reduced, and to store exhaust heat of a gas turbine in the form of a high calorific value fuel (reformed gas). Another object of the present invention is to provide a steam-injection gas turbine power generator that can improve the thermal efficiency as a whole by using the high calorific value fuel when the required power generation amount increases.

[0010]

According to the present invention, a gas turbine generator (12) comprising a compressor (12a), a combustor (12b), a turbine (12c) and a generator (11).
An exhaust heat recovery boiler (14) for generating steam by the exhaust heat of the turbine; a mixer (16) for mixing fuel gas and the steam; and a position between the gas turbine generator and the exhaust heat recovery boiler. A reformer for reforming a fuel gas into a reformed gas containing hydrogen by exhaust heat of a turbine, a reformed gas storage device for storing the reformed gas, and a reformed gas storage device And a reformed gas amount adjuster (21) for adjusting the amount of reformed gas supplied to the combustor from the above.

According to the configuration of the present invention, the mixer (1)
6) and a reformer (18), and the fuel gas is reformed into a reformed gas containing hydrogen by the exhaust heat of the turbine, so that a large amount of heat energy is generated by the reforming reaction which is an endothermic reaction. Heat can be recovered in the form of an increased amount. Therefore, in order to maintain high-efficiency power generation when the required power generation amount is reduced, the heat energy of the exhaust heat of the gas turbine can be recovered to the maximum even if the steam injection to the gas turbine is reduced.

Further, since a reformed gas storage device (20) and a reformed gas amount controller (21) are provided, when the amount of reformed gas generated by exhaust heat recovery is larger than the required amount of the gas turbine, , The excess reformed gas is stored in a reformed gas storage device,
Conversely, if there is a shortage, it can be released from the reformed gas storage device. Therefore, the flow rate of the fuel supplied from the outside can be reduced by increasing the calorific value of the fuel gas and storing the reformed gas.

According to a preferred embodiment of the present invention, the reformed gas storage device (20) is a hydrogen storage device using a high-pressure gas storage tank, a gas accumulator, or a hydrogen storage alloy. By using the gas accumulator, the reformed gas can be stored with a simple structure. Further, by using the hydrogen storage device, only the hydrogen gas in the reformed gas can be selectively stored.

Further, according to the present invention, the fuel mixing line (32) for supplying the steam generated in the exhaust heat recovery boiler (14) to the mixer (16) and the steam directly to the combustor (12b). A steam injection line (33) to supply;
A process steam line (34) for supplying the remaining steam as process steam to the outside, the steam amount of the fuel mixing line is set to an optimum flow rate with respect to the fuel gas amount, and the steam amount of the steam injection line is set to a required power generation output. It changes according to. With this configuration, a sufficient amount of water vapor for reforming the fuel gas amount can be stably supplied from the fuel mixing line (32). In addition, a necessary amount of steam can be supplied from the steam injection line (33) in accordance with the required power generation output, and the power generation output can be secured. The surplus steam is supplied to the outside as process steam from the process steam line (34).

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. Note that the same reference numerals are used for common parts in each drawing. FIG. 1 is an overall configuration diagram of a steam injection gas turbine power generation device of the present invention. As shown in this figure, a steam injection gas turbine power generator 10 of the present invention includes a gas turbine generator 12, an exhaust heat recovery boiler 14, a mixer 16, a reformer 18, and a reformed gas storage device 2.
0 and a reformed gas amount controller 21 are provided.

The gas turbine generator 12 includes a compressor 12
a, a combustor 12b, a turbine 12c, and a generator 11. The intake air 1 is compressed by the compressor 12a, and the fuel gas is burned in the combustor 12b with the compressed air.
To rotate the turbine 12c, and the output thereof
a and the generator 11 are driven.

The exhaust heat recovery boiler 14 is located downstream of the gas turbine generator 12, and heats and evaporates the feed water 2 with the heat of the exhaust gas 4 of the turbine 12c to generate steam.
This steam is saturated steam in this example, but may be further provided with a superheater to generate superheated steam.

In FIG. 1, a steam injection type gas turbine power generator 10 of the present invention further comprises a fuel mixing line 3 for supplying steam generated by an exhaust heat recovery boiler 14 to a mixer 16.
2, a steam injection line 33 for directly supplying the steam to the combustor 12b, and a process steam line 34 for supplying the remaining steam to the outside as process steam.

The mixer 16 mixes the fuel gas with the steam generated in the heat recovery steam generator 14. Fuel gas is C
It is preferably a hydrocarbon gas such as H ₄ , C ₃ H ₈ or CH ₃ OH. The reformer 18 is located between the gas turbine generator 12 and the exhaust heat recovery boiler 14, and reforms the fuel gas 5 into a reformed gas containing hydrogen with the exhaust heat (exhaust gas 4) of the turbine 12c. In addition, this reforming reaction can be represented by equation (1). _{2CnHm + 2nH 2 O → (m} + 2n) H 2 + 2nC
O ₂ . . . (1) Further, this reforming reaction is carried out at about 500 to 9
It is known that it reacts efficiently at a high temperature of 00 ° C. and involves a large amount of endotherm.

The reformed gas storage device 20 is a hydrogen storage device using a high-pressure gas storage tank, a gas accumulator, or a hydrogen storage alloy, and stores the reformed gas. By using the gas accumulator, the reformed gas can be stored with a simple structure. Further, by using the hydrogen storage device, only the hydrogen gas in the reformed gas can be selectively stored.

The reformed gas amount controller 21 is a flow control valve provided in a reformed gas line 36 which communicates the reformed gas storage device 20 with the combustor 12b. Adjust the amount of reformed gas supplied to.

As described above, the steam injection type gas turbine power generating apparatus of the present invention uses a part of the steam generated by the exhaust heat of the gas turbine as CH ₄ , C ₃ H ₈ or CH ₃ OH as the fuel.
After that, the fuel is steam reformed by heating the mixed gas with the exhaust heat of the gas turbine, the reformed gas is injected into the combustor, and the exhaust heat of the gas turbine is used to increase the calorific value of the fuel. To improve the thermal efficiency of the gas turbine.

Further, by adding a device for storing the reformed gas, even if the demand for the exhaust heat recovery steam fluctuates, the exhaust heat recovery by the reforming operation can be maintained substantially constant.
Further, in the reformed gas storage device, when the amount of the reformed gas generated by the exhaust heat recovery is larger than the required amount required from the gas turbine, the surplus reformed gas is stored in the reformed gas storage device. In the opposite case, the shortage is discharged from the reformed gas storage device. With this configuration, in order to maintain high-efficiency power generation when the required power generation amount is reduced, heat energy of gas turbine exhaust heat can be recovered to the maximum even if steam injection to the gas turbine is reduced.

On the other hand, when the required power generation amount increases, the amount of exhaust heat recovered for the reforming operation decreases to increase the steam injection to the gas turbine, but the reformed gas stored from the reformed gas storage device is reduced. Is supplied as a gas turbine fuel, the reformed gas having an increased calorific value can be used even in this case, and the flow rate of the fuel supplied from the outside can be reduced. In other words, in the thermoelectric variable gas turbine cogeneration, even if the ratio of the amount of steam delivered to the process and the amount of power generation, that is, the so-called thermoelectric ratio changes or the required amount of power generation decreases, the amount of waste heat recovered by the reforming operation is adjusted Thereby, the exhaust heat of the gas turbine can be effectively recovered, and the fuel gas supplied from the outside can be reduced as a whole.

It should be noted that the present invention is not limited to the above-described embodiment, but can be variously modified without departing from the gist of the present invention.

[0026]

According to the above-described structure of the present invention, since the mixer 16 and the reformer 18 are provided and the fuel gas is reformed into the reformed gas containing hydrogen by the exhaust heat of the turbine, the reaction is an endothermic reaction. Through the reforming reaction, a large amount of heat energy can be recovered in the form of an increase in the calorific value of the fuel gas. Therefore, even when the required power generation amount fluctuates, it is possible to maximize the heat energy of the exhaust heat of the gas turbine by adjusting the amount of reformed gas generated. Further, since the temperature rise of the fuel gas is suppressed by the endothermic reaction, the apparent specific heat of the gas is increased, so that the temperature rise gradient in FIG. 5 is further reduced, and the recovery amount of the effective energy is further increased. Cycle efficiency is improved. Further, since the apparatus includes the reformed gas storage device 20 and the reformed gas amount controller (21), if the amount of the reformed gas generated by the exhaust heat recovery is larger than the required amount of the gas turbine, the surplus reformed gas Can be stored in the reformed gas storage device, and conversely, if there is a shortage, the portion can be released from the reformed gas storage device. Therefore, the flow rate of the fuel supplied from the outside can be reduced by increasing the calorific value of the fuel gas and storing the reformed gas.

Therefore, the steam-injection gas turbine power generator of the present invention can recover the heat energy of the exhaust heat of the gas turbine to the maximum even if the required power generation amount fluctuates, and reduce the required fuel gas amount. It has excellent effects such as reduction and improvement of thermal efficiency.

[Brief description of the drawings]

FIG. 1 is an overall configuration diagram of a steam injection gas turbine power generation device of the present invention.

FIG. 2 is an overall configuration diagram of a conventional two-fluid cycle gas turbine.

FIG. 3 is an overall configuration diagram of a partially regenerating two-fluid cycle gas turbine of the prior application.

FIG. 4 is an exhaust heat recovery diagram of FIG. 2;

FIG. 5 is an exhaust heat recovery diagram of FIG. 3;

[Explanation of symbols]

1 intake, 2 water supply, 3 combustion gas, 4 exhaust gas, 5
Fuel gas, 10 Steam injection gas turbine power generator, 1
Reference Signs List 1 generator, 12 gas turbine generator, 12a compressor, 12b combustor, 12c turbine, 14 exhaust heat recovery boiler, 16 mixer, 18 reformer, 20 reformed gas storage device, 21 reformed gas amount controller , 32 fuel mixing line, 33 steam injection line, 34 process steam line, 51 throttle valve, 52 compressor (compressor), 53 combustor (combustion chamber), 54 water treatment device, 5
5 pump, 56 superheater, 57, 58 turbine, 5
9 condenser, 60 regenerative steam injection gas turbine power generator, 61 generator (main generator) 62 waste heat recovery boiler, 63 air line, 64 main steam line, 65
Mixed gas line

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) F02C 9/40 F02C 9/40 B // F17C 11/00 F17C 11/00 C

Claims (3)

[Claims] A compressor (12a), a combustor (12b),
A gas turbine generator (12) comprising a turbine (12c) and a generator (11), an exhaust heat recovery boiler (14) for generating steam by exhaust heat of the turbine, and a mixer for mixing a fuel gas and the steam And (16) a reformer (1) located between the gas turbine generator and the exhaust heat recovery boiler, which reforms the fuel gas into a reformed gas containing hydrogen by the exhaust heat of the turbine.
8) and a reformed gas storage device (2) for storing the reformed gas.
0), and a reformed gas amount controller (21) for adjusting the amount of reformed gas supplied from the reformed gas storage device to the combustor. 2. The steam injection gas turbine power generator according to claim 1, wherein the reformed gas storage device (20) is a gas accumulator or a hydrogen storage device using a hydrogen storage alloy. . 3. A fuel mixing line (3) for supplying steam generated in an exhaust heat recovery boiler (14) to the mixer (16).
2), a steam injection line (33) for supplying the steam directly to the combustor (12b), and a process steam line (34) for supplying the remaining steam to the outside as process steam. The steam-injection gas turbine power generator according to claim 1, wherein the amount is set to an optimal flow rate with respect to the fuel gas amount, and the amount of steam in the steam injection line is changed according to a required power generation output.