JPH0783005A - Compound refuse power generation plant - Google Patents

Abstract

PURPOSE:To maintain a temperature and a steam flow quantity at constant levels for a power generation steam turbine. CONSTITUTION:A steam flow quantity to be generated from a gas turbine discharged heat recovering evaporator 23 is sought by calculation and estimation by detecting a steam flow quantity from the evaporator of a refuse incinerator 20 and detecting a pouring water flow quantity to be supplied to a pouring water temperature reducer 28 interposed between a first superheater 18 and a second superheater 19, thereby, the additional burning quantity of a combustion assisting burner 17 provided in the exhaust gas passage of a gas turbine 11 is controlled. Also, steam temperature from the first superheater 18 is detected, and the pouring water flow quantity is controlled so that this temperature may become constant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combined refuse power generation plant constructed by combining a refuse incinerator and a gas turbine.

[0002]

2. Description of the Related Art Electric power generated from a combined refuse power generation plant combined with a gas turbine is desired to be sent back to a commercial power grid for sale. In this case, it is expected that the smaller the power fluctuation, the higher the quality of the power and the higher the power selling price. The flow rate of steam generated by the waste heat recovery evaporator provided in a refuse incinerator for municipal waste, etc. constantly fluctuates greatly depending on the amount of heat generated by the refuse, for example, as shown in FIG. 6, and sometimes 60 ~ 100%
Also, the steam flow rate may change. If such steam is supplied to the steam turbine as it is to generate electric power, the output of the steam turbine changes by 50% or more in combination with the efficiency decrease due to the partial load. Further, since the fluctuation of the generated electric power is large, poor quality electric power is obtained, and when the electric power is sent back to the commercial electric power network, the commercial electric power network is adversely affected.

In one prior art solution to this problem, the steam coming from the evaporator in the refuse incinerator is
If a gas turbine with a capacity considerably larger than the capacity required to superheat to a prescribed steam temperature is installed and the exhaust heat from this gas turbine is used to obtain a constant amount of steam from the high-pressure evaporator, waste incineration will be achieved. It is possible to reduce fluctuations in the flow rate of steam sent from the evaporator of the furnace. This prior art uses a gas turbine with a large capacity as described above, and thus is not a good solution for maximizing the energy of waste.

FIG. 7 is a system diagram of another prior art combined refuse power generation plant. A superheater 2 is provided in a duct that forms an exhaust gas passage from the gas turbine 1. Steam from the exhaust heat recovery evaporator 3 of the refuse incinerator is supplied to the superheater 2, and the superheated steam is steam. It is supplied to the turbine 4 to generate electric power and is condensed in the condenser 5. A hot water boiler 6 is arranged downstream of the superheater 2 in the exhaust gas passage of the gas turbine 1.

In the prior art shown in FIG. 7, the steam sent from the evaporator 3 of the refuse incinerator is only superheated in the superheater 2 by the exhaust gas of the gas turbine 1,
The flow rate of steam entering the steam turbine 4 is the same as the flow rate of steam sent from the evaporator 3 of the refuse incinerator, and the latent heat amount when steam is condensed by the condenser 5 is the same as that of the gas turbine 1. Not the same as in the conventional refuse power plant, the repowering effect is the best. The problem with this prior art is that the output of the steam turbine 4 fluctuates almost in proportion to the steam flow rate of the evaporator 3 of the refuse incinerator as shown in FIG. Machine 6
As a result, the amount of power generated by the power supply fluctuates greatly as in FIG.

Another prior art is shown in FIG. In this prior art, the same reference numerals are given to the portions corresponding to the above-mentioned prior art in FIG. In this prior art, a high-pressure evaporator 8 is arranged on the gas turbine exhaust gas downstream side of the superheater 2, and a constant vapor flow rate is generated from the high-pressure evaporator 8.
As a result, the output of the steam turbine 4 is correspondingly increased, and the fluctuation rate of power generation is reduced. A hot water boiler 9 is further arranged downstream of the high pressure evaporator 8.

The new problem of the prior art shown in FIG. 8 is that
The amount of heat released from the condenser 5 is reduced by the flow rate of the steam generated from the high-pressure evaporator 8, and thus the thermal efficiency of the steam turbine plant is decreased. That is, the repowering effect becomes small.

Another prior art is, for example, Japanese Patent Laid-Open No. 5-599.
05. This prior art also has a configuration in which a refuse incineration boiler and a gas turbine are combined, but no measures have been taken to keep the temperature and flow rate of steam to the steam turbine driving the generator constant. As with the prior art, the rate of change in power generation is still large.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to reduce the rate of change in the amount of power generation and improve thermal efficiency even if the evaporation flow rate from the evaporator of a refuse incinerator changes greatly. Is to provide a combined refuse power generation plant.

[0010]

The present invention is directed to a gas turbine, an auxiliary combustion burner provided in an exhaust gas passage from the gas turbine, and a first superheat provided in an exhaust gas passage from the gas turbine downstream of the auxiliary combustion burner. Incinerator, a second superheater provided in the exhaust gas passage from the gas turbine on the downstream side of the first superheater, and a waste heat recovery evaporator, and incinerates the waste by supplying the steam to the second superheater. A gas turbine exhaust heat recovery evaporator, which is provided in the exhaust gas passage from the furnace and the gas turbine, on the downstream side of the second superheater and supplies the steam to the second superheater, and the steam from the second superheater. Flow rate of steam from the water injection desuperheater, which supplies water to the first superheater, the steam turbine to which steam from the first superheater is applied, the generator driven by the steam turbine, and the waste heat recovery evaporator. Flow rate detection to detect Means, a water injection flow rate control valve for supplying water to the water injection desuperheater, a water injection flow rate detection means for detecting the flow rate of water supplied to the water injection desuperheater, a steam flow rate detection means, and a water injection flow rate detection means In response to each output, the steam flow rate from the gas turbine exhaust heat recovery evaporator is estimated by the sum of the steam mass flow rate and the water injection mass flow rate, and the steam flow rate from the first superheater is approximately constant. Control means for controlling the fuel flow rate so that the value becomes a value to operate the auxiliary burner, and temperature detection means for detecting the temperature of the steam from the first superheater,
A composite waste power generation plant comprising: a control unit that responds to the output of the temperature detection unit and controls the opening degree of the water injection flow control valve so that the detected steam temperature reaches a predetermined temperature.

The present invention is also directed to a gas turbine, an auxiliary combustion burner provided in an exhaust gas passage from the gas turbine, a first superheater provided in the exhaust gas passage from the gas turbine downstream of the auxiliary combustion burner, and the gas turbine. In the exhaust gas passage from the first superheater, a second superheater provided downstream of the first superheater, and a waste heat recovery evaporator, and a waste incinerator for supplying the steam to the second superheater; and a gas turbine. In the exhaust gas passage from the second superheater, and the gas turbine exhaust heat recovery evaporator for supplying the steam to the second superheater and the steam from the second superheater are injected with the first A water injection desuperheater to be given to the superheater, a steam turbine to which the steam of the first superheater is given, a generator driven by the steam turbine,
First to detect the flow rate of steam from the waste heat recovery evaporator
From the steam flow rate detection means, the water injection flow rate control valve that supplies water to the water injection desuperheater, the water injection flow rate detection means that detects the flow rate of the water supplied to the water injection desuperheater, and the gas turbine exhaust heat recovery evaporator Of the second and second steam flow rate detecting means for detecting the steam flow rate of each of the first and second steam flow rate detecting means, and the water injection flow rate detecting means, and the sum of the respective steam mass flow rate and the water injection mass flow rate. The control means for controlling the fuel flow rate so that the steam flow from the first superheater becomes a predetermined substantially constant value to operate the auxiliary burner, and the temperature detecting means for detecting the temperature of the steam from the first superheater. A composite waste power generation plant comprising: a control unit that responds to the output of the temperature detection unit and controls the opening degree of the water injection flow control valve so that the detected steam temperature reaches a predetermined temperature.

[0012]

According to the present invention, the flow rate of steam from the waste heat recovery evaporator provided in the waste incinerator is detected by the steam flow rate detecting means, and is interposed between the first and second superheaters. Based on the flow rate of water detected by the water injection flow rate detecting means supplied to the water injection desuperheater, the flow rate of steam generated from the gas turbine exhaust heat recovery evaporator is calculated and estimated, thus obtaining the first flow rate. The flow rate of fuel supplied to the auxiliary combustion burner is controlled so that the flow rate of steam supplied from the superheater to the steam turbine becomes a substantially constant value set in advance. The temperature and flow rate of the exhaust gas from the gas turbine are kept constant.
Further, in order to keep the temperature of the steam supplied to the steam turbine constant, the temperature of the steam from the first superheater is detected by the temperature detecting means, and this temperature is set to a predetermined temperature. , Controls the opening of the water injection flow rate control valve that supplies water to the water injection desuperheater.

By actually detecting the steam flow rate from the gas turbine exhaust heat recovery evaporator, it is not necessary to estimate the steam flow rate from the gas turbine exhaust heat recovery evaporator by the above-mentioned calculation, and the auxiliary combustion burner is added. It is possible to accurately determine the amount of heating.

When the flow rate of steam sent from the waste heat recovery evaporator provided in the waste incinerator is reduced in this way, it is provided in front of the first superheater for recovering the waste heat to the gas turbine. Further, the flow rate of the fuel injected into the auxiliary combustion burner is increased to a high temperature gas, and the flow rate of steam generated by the gas turbine exhaust heat recovery evaporator which is a high pressure evaporator provided after the second superheater is increased. Further, by increasing the water injection amount of the water injection desuperheater interposed between the first and second superheaters, the first superheater outlet steam temperature is kept constant and the first superheater outlet steam flow rate is increased. This makes it possible to compensate for the decrease in the steam flow rate from the waste heat recovery evaporator. The steam flow generated from the high-pressure evaporator, which is an evaporator for recovering heat from the gas turbine, has a second superheater that evaporates waste heat from the waste incinerator at the maximum calorific value when the waste quality is set to the highest quality. About 10% of the flow rate of steam sent from the vessel, 20% at maximum
The steam flow rate shall be kept to improve the thermal efficiency and enhance the repowering effect. That is, when incinerating high-quality waste, it is possible to minimize the increase in the amount of heat released from the condenser of steam from the steam turbine, that is, to enhance the repowering effect as much as possible and to reduce the fluctuation rate of power generation.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a system diagram showing the overall construction of the present invention. The gas turbine 11 supplies the compressed air from the air compressor 12 together with the fuel to the combustor 13, and the gas turns the turbine 14 to drive the generator 15.
Exhaust gas from the gas turbine 11 is guided through a duct 16 that forms the exhaust gas passage. An auxiliary combustion burner 17 is arranged in this exhaust gas passage, a first superheater 18 is arranged downstream thereof, and a second superheater 19 is arranged further downstream thereof. The waste incinerator 20 has an evaporator 21 for incinerating municipal waste and recovering the waste heat of the waste. This evaporator 21
The steam from is led to the second superheater 19 via the line 22.

In the exhaust gas passage from the gas turbine 11,
A gas turbine exhaust heat recovery high-pressure evaporator 23 is disposed downstream of the second superheater 19. The evaporator 23 has a structure in which a large number of water pipes 26 are connected between a water drum 24 and a steam drum 25, and the steam generated in the evaporator 23 passes through a pipe line 27 and then the above-mentioned evaporator. It joins with the steam from 21 and is given to the 2nd superheater 19. Second superheater 1
A water injection desuperheater 28 is interposed between 9 and the first superheater 18, and the water from the pipe 29 is supplied to the steam from the second superheater 19.

The steam of the first superheater 18 is given to a steam turbine 31 via a pipe 30, and the steam turbine 31 drives a generator 32. The steam from the steam turbine 31 is condensed in the condenser 33.

The mass flow rate of steam from the waste heat recovery evaporator 21 is detected by the steam flow rate detecting means 34. A water injection flow rate control valve 35 for controlling the flow rate of water supplied to the water injection desuperheater 28 is interposed in the pipeline 29, and the mass flow rate of the water injection is detected by the water injection flow rate detection means 36. The detection output signals of these detecting means 34 and 36 are given to the calculating means 37. When the mass flow rate of steam detected by the steam flow rate detecting means 34 is F34 and the mass flow rate of water detected by the water injection flow rate detecting means 36 is F36, the calculating means 37 is the sum of these mass flow rates (= F34 + F3).
Based on 6), the temperature tg2 at the inlet position 38 of the evaporator 23 in the gas turbine exhaust gas passage is calculated and estimated, and the mass of steam generated by the evaporator 23 and supplied from the pipeline 27 from the gas temperature tg2. The flow rate F23 is calculated and obtained. The calculation means 37 is provided with a memory 39.

As shown in FIG. 2, the memory 39 stores the flow rate (= F34 + F36) and the gas temperature tg2 at the inlet of the evaporator 23 as a table. The gas temperature tg2 is as described above. Corresponds to the mass flow rate F23 of the vapor generated from the evaporator 23. The calculation means 37 responds to the target vapor mass flow rate F0 set by the setter 40, and when the equation 1 is satisfied, the calculation means 37 determines the fuel flow rate intervening in the middle of the fuel 41 supplied to the auxiliary burner 17. The auxiliary burner 17 is controlled by controlling the opening degree of the control valve 42.
The refueling amount is controlled by adjusting the flow rate of fuel supplied to.

(F34 + F36 + F23) <F0 (1) Thus, the sum of the mass flow rates of steam on the left side of the equation 1 is (= F34
The reheating amount of the auxiliary burner 17 is adjusted so that + F36 + F23) becomes the target value F0. As a result, the mass flow rate of steam supplied from the first superheater 18 to the steam turbine 31 via the pipe 30 is maintained at the target value F0 (= F34 + F36 + F23).

When the expression 1 is not satisfied, that is, when (F34 + F36 + F23) ≧ F0 (2), the fuel flow rate control valve 42 is made to have a very small opening degree or is kept closed. The flow rate of fuel supplied according to the set opening degree of the fuel flow rate control valve 42 is detected by the fuel flow rate detecting means 43, and the subtractor 44
The negative feedback control is performed.

The temperature of the steam supplied from the first superheater 18 to the conduit 30 is detected by the temperature detecting means 45, and the detected temperature is set at the target temperature ts set by the temperature setting device 46.
The subtracting means 47 operates to control the opening degree of the water injection flow control valve 35 so as to be zero, and when the detected temperature is low, the opening degree is controlled to be small. In this way, the temperature of the steam supplied to the steam turbine 31 via the conduit 30 is kept constant at the target temperature ts0.

To explain further, the steam sent from the evaporator 21 of the refuse incinerator 20 enters the second superheater 19. Exhaust gas from the gas turbine 11 is exhaust gas duct 1
After entering 6, the first and second superheaters 18, 19 are entered. First
An auxiliary combustion burner 17 that superheats exhaust gas is provided in the duct 16 upstream of the second superheaters 18 and 19, and a fuel flow rate control valve 42 is installed on the fuel inlet side of the auxiliary combustion burner 17. Fuel is constantly sent to the auxiliary burner 17. However, when the vapor flow rate sent from the evaporator 21 of the refuse incinerator 20 is the maximum, the fuel flow rate is very small and does not hinder the thermal efficiency of the power generation plant of the present case. The turndown ratio of the auxiliary burner 17 is 1 /
It is about 100.

An evaporator 23 is provided downstream of the second superheater 19, and high-pressure saturated steam is generated by the exhaust heat of the gas turbine,
This saturated steam merges with the steam from the evaporator 21 of the refuse incinerator 20 and enters the second superheater 19. This high-pressure saturated steam flow rate differs depending on the gas turbine capacity and the waste incinerator plant scale. The capacity of the gas turbine 11 is selected so that the flow rate of the high-pressure saturated steam from the evaporator 23 is minimized when the flow rate of the steam sent from the evaporator 21 of the refuse incinerator plant to the first superheater 19 is maximum. . The gas heat exchange state in this case is shown by the solid line L1 in FIG. 3, and the vapor heat exchange state is shown by the solid line L2 in FIG. In the description given with reference to FIG. 3, the auxiliary combustion burner 17 has an extremely small amount of reheating or is zero. The exhaust gas temperature tg11 of the gas turbine 11 is, for example, 550 ° C., which is a constant value, and the exhaust gas flow rate thereof is a constant value. The gas having this temperature tg11 enters from the first superheater 18, the outlet temperature of the second superheater 19 becomes tg21, and the outlet temperature of the evaporator 23 becomes gas temperature tg31. The temperature tg21 is, for example, 430 ° C., and the temperature tg31
Is 350 ° C., for example. On the other hand, the mass flow rate Gr1 (kg of the steam sent from the evaporator 21 of the refuse incinerator 20 (kg
/ H) steam merges with the steam from the evaporator 23, the temperature at this time is ts11, and the temperature is once reduced by the water injection cooling valve 28, and at the outlet of the first superheater 18, the steam temperature becomes ts21. Sent to the steam turbine 31. The temperature ts21 is
For example, it is 500 ° C. The steam from the evaporator 23 is saturated steam having a pressure Ps (ata), and the steam sent from the evaporator 21 of the waste incinerator 20 plant has the same pressure p.
Although it is s (ata), it may be slightly overheated and the temperatures of the two may be different, but the temperatures are the same here for convenience of description.

Next, the evaporator 2 of the plant of the refuse incinerator 20
It is assumed that the flow rate of steam sent from No. 1 is reduced to the mass flow rate Gr2 (kg / h) as indicated by the broken line L3 in FIG. At this time, if the gas temperature at the inlet of the first superheater 18 is tg11 as described above, the state of heat exchange of steam is as shown by the broken line L4 in FIG. That is, the amount of heat collected in the first and second superheaters 18 and 19 is reduced, and the gas temperature at the outlet of the second superheater 19 is t.
It rises from g21 to tg22, and the steam temperature at the outlet of the first superheater 18 rises to ts21. On the other hand, the evaporator 2
Since the inlet gas temperature of No. 3 also rises to tg22 as described above, the evaporation flow rate of the evaporator 23 slightly increases, but the vapor flow rate fluctuation ΔGr (=) sent from the evaporator 21 of the refuse incinerator 20 plant. It is negligible as compared with Gr1-Gr2).

Therefore, the state of heat exchange when the additional heating amount of the auxiliary burner 17 is increased will be described with reference to FIG. By burning the auxiliary combustion burner 17,
When the inlet gas temperature of the superheater 18 is increased from tg11 to tg12, the state of the one-dot chain line L5 is established.
The gas temperature at the outlet of the evaporator 23 can be reduced to the same temperature tg31 as described in connection with FIG. When the temperature of the gas contacting the water pipe 26 of the evaporator 23 is ts, tg3 = ts + Δt (3), and the temperature t is calculated from the minimum terminal temperature difference Δt of the evaporator 23.
g31 is the lowest temperature.

In this case, the gas temperature at the inlet of the evaporator 23 naturally rises, so that the evaporation flow rate by the evaporator 23 increases. If this evaporation flow rate is the vapor flow rate variation difference ΔG sent from the evaporator 21 of the plant of the refuse incinerator 20.
If it can be made equal to r (= Gr1−Gr2), the steam flow rate entering the steam turbine 31 will always be constant, and the steam turbine 31 will have a constant load. Waste incinerator 20 as described above
The flow rate of steam sent from the evaporator 21 of the plant
The time of Gr0 (kg / h) is considered as the planned point, and the gas temperature at the outlet of the evaporator 23 is tg30 (° C) at this time. When the steam flow rate Gr (kg / h) is sent from the evaporator 21 of the plant of the refuse incinerator 20, what is the gas temperature tg11 at the inlet to the first superheater 18, that is, the auxiliary combustion burner 18? It is possible to previously determine how much the flow rate of the fuel to be sent should be set to the predetermined outlet gas temperature of the evaporator 27 to be tg30 [° C]. The steam flow rate sent from the evaporator 21 of the refuse incinerator 20 is detected by the steam flow rate detection means 34, and the calculation means 37 sends a signal commensurate with the detected steam flow rate. A signal is sent to the fuel flow rate control valve 42 together with the signal to control the fuel flow rate so that the set fuel flow rate is achieved. In this case, the outlet steam temperature ts22 of the first superheater 18 becomes high as shown by the one-dot chain line L6 in FIG.
At this time, no water is injected into the water injection desuperheater 28. Therefore, the superheaters 18 and 19 are divided into two as shown in the embodiment of FIG. 1, and the steam temperature is detected by the steam temperature detecting means 45.
Sending to a subtractor 47 for steam temperature control, setting means 46
The temperature of the water injection desuperheater 2 is adjusted by collating it with the set temperature ts0 set in step 3 and sending a deviation signal to the water injection flow control valve 35.
The flow rate of water injection into 8 is adjusted to control the steam temperature at the outlet of the first superheater 18 to be the set value ts0.

Of course, since the amount of the water injection flow rate Gw from the water injection flow rate control valve 35 is added to the generated steam flow rate from the evaporator 23, the fuel flow rate supplied to the auxiliary burner 17 and the evaporator 23.
The relationship with the supply steam flow rate generated and supplied by the above is stored in the memory 39 of the calculating means 37 as described above, the water injection flow rate is detected by the water injection flow rate detecting means 36, and the amount is calculated as a correction term. It will send the output signal of the means 37.

According to a trial calculation by the present inventor, the waste incinerator 2
0 is 500 tons / day, and when the auxiliary combustion burner 17 is not provided, the output fluctuation range of the power generation amount by the steam turbine 31 is large at 100% to 60%, but the auxiliary combustion burner 17 is provided according to the present invention, as described above. With this configuration, the fluctuation range of the power generation output can be significantly reduced to 100% to 80%, and it is confirmed that high-quality power can be supplied. At this time, the auxiliary burner 1
It was confirmed that the flow rate of the fuel supplied to No. 7 was 0.6 t / h, which was within a range with almost no problem.

FIG. 5 is a system diagram of another embodiment of the present invention. This embodiment is similar to the previous embodiment, and corresponding parts bear the same reference numerals. In the embodiment described above, the evaporator 2
The steam flow rate of No. 3 was calculated and estimated by the calculation means 37, but in the embodiment of FIG. 5, the steam flow rate detection means 49 is provided in the pipeline 27 to actually detect and calculate the mass flow rate F23. It is given to the means 37. As a result, the memory 39 is omitted. The control of the fuel flow rate control valve 42 is the same as that of the above-described embodiment.

[0031]

As described above, according to the present invention, the flow rate of steam from the waste heat recovery evaporator provided in the waste incinerator and the water injection reduction interposed between the second and first superheaters. The steam flow rate from the gas turbine exhaust heat recovery evaporator is calculated and estimated based on the flow rate of water injected into the warmer, and the additional heating amount of the auxiliary combustion burner is controlled, thus making the steam turbine the first superheater. The flow rate of steam supplied from is kept almost constant. In addition, the temperature of the steam supplied from the first superheater to the steam turbine is detected to control the flow rate of water injection to the water injection desuperheater,
This keeps the temperature of the steam supplied to the steam turbine constant. Further, the amount of steam to be reheated by the auxiliary combustion burner is determined by actually detecting the flow rate of steam generated from the gas turbine exhaust heat recovery evaporator. As a result, it is necessary to use a gas turbine having a very large capacity from the gas turbine capacity that is thermodynamically appropriate, that is, the capacity of the gas turbine that maximizes the repowering effect that increases the output of the conventional refuse power generation plant most efficiently. Therefore, the thermal efficiency will be improved.

According to the present invention, the output fluctuation range of the steam turbine is reduced even when the quality of the waste in the waste incinerator is reduced and the amount of evaporation from the waste heat recovery evaporator provided in the waste incinerator is decreased. Can be kept low, for example, on the order of 10%, and high-quality power can be generated.

[Brief description of drawings]

FIG. 1 is a system diagram of an embodiment of the present invention.

FIG. 2 is a diagram for explaining a table stored in a memory 39 provided in a calculation means 37 of the embodiment shown in FIG.

FIG. 3 is a diagram showing a state of heat exchange when the amount of additional heating of the auxiliary combustion burner 17 in the embodiment of FIG. 1 is very small or zero.

FIG. 4 is a diagram showing a heat exchange state for explaining the operation of the present invention by operating the auxiliary burner 17.

FIG. 5 is a system diagram of another embodiment of the present invention.

FIG. 6 is a graph showing a change over time in the flow rate of steam generated by a waste heat recovery evaporator in a waste incinerator.

FIG. 7 is a prior art system diagram.

FIG. 8 is a system diagram of another prior art.

[Explanation of symbols]

 11 Gas Turbine 16 Exhaust Duct 17 Auxiliary Burner 18 First Superheater 19 Second Superheater 20 Waste Incinerator 21 Waste Waste Heat Recovery Evaporator 23 Gas Turbine Waste Heat Recovery Evaporator 28 Water Injection Desuperheater 31 Steam Turbine 32 Power Generation Machine 34 Steam flow rate detection means 35 Water injection flow rate control valve 36 Water injection flow rate detection means 37 Calculation means 39 Memory 42 Fuel flow rate control valve 44 Subtractor 45 Steam temperature detection means 46 Temperature setter 47 Subtractor

Claims (2)

[Claims] 1. A gas turbine, an auxiliary combustion burner provided in an exhaust gas passage from the gas turbine, a first superheater provided in the exhaust gas passage from the gas turbine downstream of the auxiliary combustion burner, and an exhaust gas from the gas turbine. In the passage, there is a second superheater provided on the downstream side of the first superheater, a waste heat recovery evaporator, and a waste incinerator that supplies the steam to the second superheater, and exhaust gas from the gas turbine. A gas turbine exhaust heat recovery evaporator, which is provided in the passage downstream of the second superheater and supplies the steam to the second superheater, and the steam from the second superheater is injected into the first superheater. A water injection desuperheater to be given, a steam turbine to which the steam of the first superheater is given, a generator driven by the steam turbine, and a steam flow rate detection means for detecting the flow rate of steam from the waste heat recovery evaporator. , Water cooling In response to each output of the water injection flow rate control valve that supplies water to the The steam flow rate from the gas turbine exhaust heat recovery evaporator is estimated by the sum of the steam mass flow rate and the water injection mass flow rate, and the fuel flow rate is adjusted so that the steam flow rate from the first superheater becomes a predetermined constant value. Control means for controlling the burner burner to operate the auxiliary combustion burner, temperature detecting means for detecting the temperature of the steam from the first superheater, and the detected steam temperature in response to the output of the temperature detecting means reaches a predetermined temperature. And a control means for controlling the opening degree of the water injection flow control valve. 2. A gas turbine, an auxiliary combustion burner provided in an exhaust gas passage from the gas turbine, a first superheater provided in the exhaust gas passage from the gas turbine downstream of the auxiliary combustion burner, and exhaust gas from the gas turbine. In the passage, there is a second superheater provided on the downstream side of the first superheater, a waste heat recovery evaporator, and a waste incinerator that supplies the steam to the second superheater, and exhaust gas from the gas turbine. A gas turbine exhaust heat recovery evaporator, which is provided in the passage downstream of the second superheater and supplies the steam to the second superheater, and the steam from the second superheater is injected into the first superheater. The water injection desuperheater to be given, the steam turbine to which the steam of the first superheater is given, the generator driven by the steam turbine, and the flow rate of steam from the waste heat recovery evaporator
From the steam flow rate detection means, the water injection flow rate control valve that supplies water to the water injection desuperheater, the water injection flow rate detection means that detects the flow rate of the water supplied to the water injection desuperheater, and the gas turbine exhaust heat recovery evaporator In response to the outputs of the second steam flow rate detecting means for detecting the steam flow rate, the first and second steam flow rate detecting means, and the water injection flow rate detecting means, and the sum of the respective steam mass flow rate and water injection mass flow rate. Control means for controlling the fuel flow rate to operate the auxiliary burner so that the steam flow rate from the first superheater becomes a predetermined substantially constant value, and temperature detection means for detecting the temperature of the steam from the first superheater, A composite refuse power generation plant comprising: a control unit that responds to the output of the temperature detection unit and controls the opening degree of the water injection flow control valve so that the detected steam temperature becomes a predetermined temperature.