JP2021060012A - Humid air utilization power generating system and operation method of the same - Google Patents

Abstract

To provide a humid air utilization power generating system which extends a range of a usable fuel without limiting its fuel to relatively clean gas fuels, such as liquefaction natural gas, and deals with diversification of the fuel including, for example, oil fuels.SOLUTION: A humid air utilization power generating system of the invention has: a gas turbine 2 which is driven by using combustion gas 9 supplied from a combustor 3; an exhaust heat recovery boiler 11 which generates steam using exhaust gas 10 exhausted from the gas turbine 2 as a heat source; and a water recovery device 20 which recovers a water component from the exhaust gas 14 exhausted from the exhaust heat recovery boiler 11. The humid air utilization power generating system supplies the steam generated by the exhaust heat recovery boiler 11 to the combustor 3 and includes: a water quality inspection device 30 which inspects a water quality of recovery water 15 recovered by the water recovery device 20; and a recovery water storage tank 31 which stores the recovery water 15 according to water quality conditions of the recovery water 15 inspected by the water quality inspection device 30.SELECTED DRAWING: Figure 1

Description

The present invention relates to a high-humidity air-based power generation system and a method for operating a high-humidity air-based power generation system.

In recent years, the environment surrounding the electric power industry has changed in various ways, and various power generation systems have been proposed. As one of such power generation systems, there is a high humidity air power generation system.

As a background technique in this technical field, there is Japanese Patent Application Laid-Open No. 2017-15019 (Patent Document 1).

Patent Document 1 describes a high-humidity air-based power generation system. The high-humidity air-utilizing power generation system described in Patent Document 1 uses the exhaust gas discharged from the gas turbine and recovers from the exhaust heat recovery boiler that generates steam and the exhaust gas discharged from the exhaust heat recovery boiler. A water recovery device that collects water, a recovery water system that circulates a part of the recovered water as circulating water to the water recovery device, and another part of the recovered water as water supply for the exhaust heat recovery boiler. A first pH adjusting device that adjusts the water supply system to be supplied and the reclaimed water flowing through the recovery water system to the first pH value, and a second pH adjusting device that adjusts the reclaimed water flowing through the water supply system to the second pH value. It has a pH adjusting device of the above, and a control device 100 for controlling a first pH adjusting device and a second pH adjusting device (see summary).

JP-A-2017-15019

The high-humidity air-utilizing power generation system described in Patent Document 1 uses a sealed component device (for example, a gas turbine, an exhaust heat recovery boiler, a water recovery device, a combustor) for a working fluid (for example, exhaust gas, recovery). Water, water supply, steam, combustion gas) circulates.

However, in the high-humidity air-utilizing power generation system described in Patent Document 1, since the working fluid circulates in the sealed component equipment, for example, the combustion gas generated by the combustion of fuel and air is chemically converted into combustion gas. If stable impurities are generated, the impurities may circulate in the sealed components and increase in the sealed components.

In particular, when this impurity is an impurity that damages a component device such as a gas turbine, such as sulfur, it becomes difficult to ensure the mechanical reliability of the component device such as a gas turbine, resulting in high humidity. The operation of the separated air power generation system may be restricted.

For this reason, in a high-humidity air-utilizing power generation system, a relatively clean gas fuel such as liquefied natural gas, which is less likely to generate impurities in the combustion gas, is generally used as the fuel.

Therefore, the present invention expands the range of fuels that can be used without being limited to relatively clean gas fuels such as liquefied natural gas, and diversifies fuels including oil fuels, for example. Provide an operation method of a high-humidity air-utilizing power generation system and a high-humidity air-using power generation system corresponding to the change.

In order to solve the above problems, the high-humidity air-utilizing power generation system of the present invention generates steam by using a gas turbine driven by using combustion gas supplied from a combustor and exhaust gas discharged from the gas turbine as a heat source. It has an exhaust heat recovery boiler and a water recovery device that recovers water from the exhaust gas discharged by the exhaust heat recovery boiler, and supplies steam generated by the exhaust heat recovery boiler to the combustor. It is characterized by having a water quality inspection device for inspecting the quality of the recovered water collected by the water recovery device, and a recovery water storage tank for storing the recovered water depending on the water quality conditions of the recovered water inspected by the water quality inspection device. ..

Further, in order to solve the above problems, the operation method of the high humidity air utilization power generation system of the present invention uses the combustion gas supplied from the combustor, drives the gas turbine, and exhaust gas discharged from the gas turbine. Is used as a heat source, steam is generated by the exhaust heat recovery boiler, water is recovered from the exhaust gas discharged by the exhaust heat recovery boiler by the water recovery device, and the steam generated by the exhaust heat recovery boiler is supplied to the combustor. The quality of the recovered water collected by the water recovery device is inspected by the water quality inspection device, and the recovered water is stored in the recovery water storage tank according to the water quality conditions of the recovered water inspected by the water quality inspection device. It is characterized by that.

According to the present invention, the range of fuels that can be used is expanded without being limited to relatively clean gas fuels such as liquefied natural gas, and a variety of fuels including oil fuels, for example. It is possible to provide an operation method of a high-humidity air-utilizing power generation system and a high-humidity air-using power generation system corresponding to the change.

Issues, configurations, and effects other than those described above will be clarified by the explanation of the examples below.

It is explanatory drawing explaining the schematic structure of the high humidity air utilization power generation system described in Example 1. FIG. It is explanatory drawing explaining the operation method of the high humidity air utilization power generation system described in Example 1. FIG. It is explanatory drawing explaining the schematic structure of the water recovery apparatus of the high humidity air utilization power generation system described in Example 2. FIG. It is explanatory drawing explaining the operation method of the high humidity air utilization power generation system described in Example 2. FIG.

Hereinafter, the operation method of the high-humidity air-utilizing power generation system and the high-humidity air-using power generation system of the present invention will be described with reference to the drawings. In addition, substantially the same or similar configurations are designated by the same reference numerals, and when the explanations are duplicated, the explanations may be omitted.

First, a schematic configuration of the high-humidity air-based power generation system described in Example 1 will be described.

FIG. 1 is an explanatory diagram illustrating a schematic configuration of a high-humidity air-utilizing power generation system described in the first embodiment.

The high-humidity air-utilizing power generation system described in Example 1 includes a gas turbine 2, an exhaust heat recovery boiler 11, and a water recovery device 20.

The gas turbine 2 is driven by using the combustion gas 9 supplied from the combustor 3. In the combustor 3, steam 12 is added to the compressed air 7 supplied from the compressor 1, and the compressed air 7, steam 12, and gas fuel 8a are combined with a relatively clean gas fuel 8a such as liquefied natural gas. To generate combustion gas 9. The compressor 1 sucks in air 6 and compresses it to generate compressed air 7.

That is, the compressor 1 compresses the air 6 to generate the compressed air 7, the combustor 3 burns the compressed air 7 and the gas fuel 8a, and the steam 12 is added to the combustion field of the combustor 3. Combustion gas 9 is generated, and the gas turbine 2 uses and drives the combustion gas 9.

As described above, in the high humidity air utilization power generation system described in the first embodiment, steam (humidity) 12 is added to the compressed air (combustion air) 7 supplied to the combustor 3 to humidify the compressed air 7. However, this is a power generation system that uses the humidified compressed air 7 (high-humidity air) and can generate power with high efficiency with simple components.

Then, in the high-humidity air-utilizing power generation system described in the first embodiment, the combustion gas 9 (gas turbine) generated by the combustor 3 by adding the steam 12 to the combustion field where the compressed air 7 and the gas fuel 8a are burned. The flow rate of the combustion gas 9) supplied to 2 is increased, the output of the gas turbine 2 is increased, and the amount of power generated by the generator 5 is increased.

In the high humidity air power generation system described in the first embodiment, the steam 12 is supplied to the combustion field, but the present invention is not limited to this, and the compressed air 7 flows down from the compressor 1 to the combustor 3. The steam 12 may be supplied to the flow path through which the combustion gas 9 flows from the compressor 3 to the gas turbine 2.

Further, the compressor 1 is connected to the starting device (starting motor) 4. The compressor 1 is activated by the activation of the activation device 4, compresses the air 6, and produces the compressed air 7. Further, the gas turbine 2 is connected to the generator 5, and when the gas turbine 2 is driven, the generator 5 is driven to generate electricity. The gas turbine 2 is also connected to the starter 4 and is started by starting the starter 4.

Further, in the high humidity air utilization power generation system described in the first embodiment, the oil fuel 8b is supplied to the combustor 3, and the gas fuel 8a and the oil fuel 8b can be switched and used. That is, the combustor 3 can burn the compressed air 7 and the oil fuel 8b, add the steam 12 to the combustion field, and generate the combustion gas 9. The gas fuel 8a is supplied from the gas fuel supply system, and the oil fuel 8b is supplied from the oil fuel supply system to the combustor 3.

That is, the high-humidity air-utilizing power generation system described in the first embodiment can be used by switching between the gas fuel 8a and the oil fuel 8b.

Further, the exhaust heat recovery boiler 11 generates steam 12 using the exhaust gas 10 discharged from the gas turbine 2 (the exhaust gas 10 contains water (moisture)) as a heat source. A steam generator 13 is installed inside the exhaust heat recovery boiler 11, and heat is exchanged between the exhaust gas 10 discharged from the gas turbine 2 and the water supply 17. Then, the exhaust heat recovery boiler 11 generates the compressed air 7 or the steam 12 to be added to the combustion gas 9 from the water supply 17.

The exhaust gas 10 discharged from the gas turbine 2 is supplied to the exhaust heat recovery boiler 11, and the steam generator 13 exchanges heat with the water supply 17, and the temperature is low (lower than the exhaust gas 10). It becomes the exhaust gas 14 and is discharged from the exhaust heat recovery boiler 11. That is, the exhaust gas 10 is heat-exchanged by the exhaust heat recovery boiler 11 (steam generator 13) to become the low-temperature exhaust gas 14, and is supplied to the water recovery device 20. Then, the steam 12 generated by the exhaust heat recovery boiler 11 is added to the compressed air 7 and supplied to the combustor 3.

Further, the water recovery device 20 has a watering device 21 and a filling 22 installed therein, and the watering device 21 cools the filling 22 by sprinkling circulating water 18 on the filling 22. That is, the water recovery device 20 recovers water from the exhaust gas 14 discharged from the exhaust heat recovery boiler.

The exhaust gas 14 is gas-liquid separated by contacting with the filling 22 cooled by the watering device 21. The separated gas component is discharged to the atmosphere as exhaust gas 19. The liquid component to be separated falls as the recovered water 45 in the direction of gravitational action and is recovered at the bottom of the water recovery device 20.

The recovered water 15 (hereinafter, referred to as “reclaimed water 15”) collected at the bottom of the water recovery device 20 is supplied to the circulating water cooler 24 by the circulating water pump 23. The recovered water 15 supplied to the circulating water cooler 24 is cooled by the cooling water 16 in the circulating water cooler 24.

The recovered water 15 cooled by the circulating water cooler 24 is supplied to the watering device 21 as circulating water (water for sprinkling) 18, and is sprinkled from the watering device 21. Further, the recovered water 15 cooled by the circulating water cooler 24 is supplied to the exhaust heat recovery boiler 11 as water supply 17, and heat is exchanged with the exhaust gas 10. Then, steam 12 is generated from the water supply 17.

That is, the recovered water 15 cooled by the circulating water cooler 24 is the circulating water 18 sprinkled on the sprinkler 21 and the water supply 17 supplied to the exhaust heat recovery boiler 11 after being cooled by the circulating water cooler 24. Used for.

The water supply 17 is used as the water supply 17 that is once stored in the circulating water storage tank (replenishment water tank) 25 and supplied to the exhaust heat recovery boiler 11. The water supply 17 stored in the circulating water storage tank 25 is supplied to the exhaust heat recovery boiler 11 by the water supply pump 26.

Further, a circulating water storage tank inlet valve 35 is installed in the pipe to which the water supply 17 is supplied to the exhaust heat recovery boiler 11. The circulating water storage tank inlet valve 35 is installed between the branch point between the circulating water 18 and the water supply 17 and the circulating water storage tank 25.

The high-humidity air-utilizing power generation system described in Example 1 has a water quality inspection device 30 for inspecting the water quality of the recovered water 15 (for example, the concentration of impurities contained in the recovered water 15). As a result, the water quality of the recovered water 15 can be monitored (inspected).

The water quality inspection device 30 monitors whether or not the water quality of the recovered water 15 exceeds a predetermined allowable value (hereinafter, referred to as a “allowable value”) (water quality condition of the recovered water 15). For example, when the oil fuel 8b is used as the fuel, it is monitored whether or not impurities such as sulfur are generated in the recovered water 15 in excess of the permissible value.

Further, the high-humidity air-utilizing power generation system described in Example 1 has a recovered water storage tank 31 for storing the recovered water 15. Then, the recovered water 15 is supplied to the recovered water storage tank 31 by the circulating water pump 23.

The recovered water storage tank 31 is connected to a branch pipe 32 in which the recovered water 15 is branched from the pipe supplied to the circulating water cooler 24. That is, the branch pipe 32 supplies the recovered water 15 to the recovered water storage tank 31. Further, the branch pipe 32 is branched from the downstream (backflow) side of the inspection point (installation point where the water quality inspection device 30 is installed) in which the water quality of the recovered water 15 is inspected by the water quality inspection device 30.

The circulating water pump 23 is installed on the downstream (wake) side of the installation point where the water quality inspection device 30 is installed, and the branch pipe 32 is located on the downstream (wake) side of the circulating water pump 23. Branched. That is, the water quality inspection device 30 is installed on the suction side of the circulating water pump 23, and the branch pipe 32 is installed on the discharging side of the circulating water pump 23.

A recovered water circulation water valve 34 is installed in the pipe to which the recovered water 15 is supplied to the circulating water cooler 24, and a recovered water storage tank valve 33 is installed in the branch pipe 32. The recovered water circulation water valve 34 is installed between the branch point of the branch pipe 32 and the circulating water cooler 24, and the recovered water storage tank valve 33 is a branch point of the branch pipe 32 and the recovered water storage tank 31. It will be installed in between.

Then, in the high humidity air utilization power generation system described in the first embodiment, when the water quality of the recovered water 15 exceeds the permissible value, the recovered water circulation water valve 34 is closed and the recovered water storage tank valve 33 is closed. It is opened and the recovered water 15 is stored in the recovered water storage tank 31.

That is, according to the water quality condition of the recovered water 15 inspected by the water quality inspection device 30, the recovered water 15 is stored in the recovered water storage tank 31 as the recovered water 15 supplied to the recovered water storage tank 31.

In this way, when the water quality inspection device 30 detects that impurities are generated in the recovered water 15 in excess of the permissible value, the recovered water storage tank valve 33 is opened based on the detection result. Then, the recovered water circulation water valve 34 is closed.

For example, a control device (not shown) may instruct the opening / closing of the recovered water storage tank valve 33 and the recovered water circulating water valve 34 based on the detection result. The recovery water storage tank valve 33 and the recovery water circulation water valve 34 are opened and closed artificially or automatically.

When the water quality of the recovered water 15 does not exceed the permissible value (if it is less than the permissible value), the recovered water circulation water valve 34 is opened and the recovered water 15 is supplied to the circulating water cooler 24.

Then, when the water quality of the recovered water 15 is equal to or less than the permissible value, first, a sprinkling operation (the recovered water 15 supplied to the circulating water cooler 24 is used as the circulating water 18 and supplied to the water recovery device 20. Operation: The operation of driving the circulating water pump 23) is executed.

After that, at the timing when a certain period of time elapses, the recovered water storage tank valve 33 is closed, the circulating water storage tank inlet valve 35 is opened, and the water recovery operation (recovered water supplied to the circulating water cooler 24) is performed together with the sprinkling operation. Operation of using 15 as water supply 17 and supplying it to the exhaust heat recovery boiler 11: operation of driving the circulating water pump 23 and the water supply pump 26: In the first embodiment, the water recovery operation is a humidification operation (compressed air 7 and steam 12). Has the same meaning as the operation) to which is added and supplied to the combustor 3.

Further, the high-humidity air-utilizing power generation system described in Example 1 is connected to the circulating water storage tank 25, and the recovered water 15 (recovered surplus water in the circulating water storage tank 25) is stored in the surplus circulating water storage tank 25. ) Is discharged to the outside of the system (outside the system). As a result, this recovered surplus water can be discharged to the outside of the system.

Further, the high-humidity air-utilizing power generation system described in Example 1 is connected to the recovered water storage tank 31, and the recovered water 15 (recovered surplus water in the recovered water storage tank 31) is stored in the surplus recovered water storage tank 31. ) Is discharged to the outside of the system. When the recovered water 15 stored in the recovered water storage tank 31 is discharged to the outside of the system, the recovered water 15 stored in the recovered water storage tank 31 is appropriately treated for environmental pollution, and the system is used. Discharge to the outside. As a result, this recovered surplus water can be discharged to the outside of the system.

Further, the high-humidity air-utilizing power generation system described in the first embodiment has a pipe 36 that is connected to the recovered water storage tank 31 and supplies the recovered water 15 stored in the recovered water storage tank 31 to the water recovery device 20. .. A pump 37 is installed in the pipe 36. As a result, the recovered water 15 stored in the recovered water storage tank 31 is supplied to the water recovery device 20.

As described above, the high-humidity air-utilizing power generation system described in the first embodiment uses the combustion gas 9 supplied from the combustor 3 to drive the gas turbine 2 and the exhaust gas 10 discharged from the gas turbine 2. It has an exhaust heat recovery boiler 11 that generates steam 12 as a heat source and a water recovery device 20 that recovers water from the exhaust gas 14, and supplies the steam 12 generated by the exhaust heat recovery boiler 11 to the combustor 3. It is a thing. Then, the water quality inspection device 30 for inspecting the water quality of the recovered water 15 (recovered water 15 collected at the bottom of the water recovery device 20) collected by the water recovery device 20 and the recovered water 15 (recovered water 15) inspected by the water quality inspection device 30. The bottom of the water recovery device 20 has a recovered water storage tank 31 for storing the recovered water 15 depending on the water quality conditions of the recovered water 15).

Further, in the operation method of the high humidity air utilization power generation system described in the first embodiment, the combustion gas 9 supplied from the combustor 3 is used to drive the gas turbine 2 and the exhaust gas discharged from the gas turbine 2. Using 10 as a heat source, steam 12 is generated by the exhaust heat recovery boiler 11, water is recovered from the exhaust gas 14 by the water recovery device 20, and the steam 12 generated by the exhaust heat recovery boiler 11 is used in the combustor 3. It is to supply. Then, the water quality of the recovered water 15 (recovered water 15 collected at the bottom of the water recovery device 20) collected by the water recovery device 20 is inspected by the water quality inspection device 30, and the recovered water inspected by the water quality inspection device 30. The recovered water 15 is stored in the recovered water storage tank 31 according to the water quality conditions of (recovered water 15 collected at the bottom of the water recovery device 20).

As a result, even when oil fuel 8b is used as the fuel and impurities are generated in the recovered water 15 in excess of the permissible value, impurities are generated in excess of the permissible value. The recovered water 15 (working fluid) does not circulate in the constituent equipment such as the gas turbine 2 constituting the power generation system.

Then, it is possible to prevent impurities from damaging the constituent equipment such as the gas turbine 2 and ensure the mechanical reliability of the constituent equipment such as the gas turbine 2.

That is, the high-humidity air-based power generation system described in Example 1 is not limited to the relatively clean gas fuel 8a such as liquefied natural gas, and the range (options) of usable fuels is expanded. It is possible to cope with the diversification of fuels including oil fuel 8b.

In this way, since the water quality of the recovered water 15 is inspected by the water quality inspection device 30, the choices of fuels that can be used are expanded, and various operation methods of the high humidity air utilization power generation system can be executed. ..

Next, an operation method of the high-humidity air-based power generation system described in the first embodiment will be described.

FIG. 2 is an explanatory diagram illustrating an operation method of the high-humidity air-utilizing power generation system described in the first embodiment.

Here, in particular, the gas turbine 2 is operated from the start to the low load state with the oil fuel 8b, the oil fuel 8b is switched to the gas fuel 8a in the low load state, and the rated load state is operated with the gas fuel 8a. The operation method of the high-humidity air-based power generation system will be explained.

FIG. 2A is a schematic diagram simplifying the generator output (output of the generator 5) in the operation method of switching from the oil fuel 8b to the gas fuel 8a.

FIG. 2B is a schematic view simply showing the open state of the recovered water circulation water valve 34.

FIG. 2C is a schematic view simply showing the open state of the recovered water storage tank valve 33.

Further, in FIG. 2, t1 is the timing of starting (parallel) of the gas turbine 2 in the oil fuel 8b (the gas turbine 2 is connected to the generator 5), and t2 reaches the low load state in the oil fuel 8b. At the timing, t4 is the timing when the oil fuel 8b is switched to the gas fuel 8a in a low load state and the water quality of the recovered water 15 becomes equal to or less than the allowable value, and at t5, the load increase of the gas turbine 2 is started with the gas fuel 8a. At the same time, a certain time elapses after the quality of the recovered water 15 becomes equal to or less than the allowable value, t6 is the timing when the gas fuel 8a reaches the rated load state, and t7 is the load drop from the rated load state. The start timing and t8 indicate the timing of stopping (disconnecting) the gas turbine 2 (the gas turbine 2 is disconnected from the generator 5), respectively.

As shown in FIG. 2A, at t1, the output of the generator 5 starts the load operation of the gas turbine 2 with the oil fuel 8b, reaches the low load state with the oil fuel 8b at t2, and has a constant load. At t4, the oil fuel 8b is switched to the gas fuel 8a, the water quality of the recovered water 15 becomes less than the permissible value, and at t5, the load of the gas turbine 2 starts to increase with the gas fuel 8a and is recovered. After a certain period of time has passed since the water quality of the water 15 became less than the permissible value, at t6, the gas fuel 8a reached the rated load state and was operated at a constant load, and at t7, the load dropped from the rated load state. It is started, and at t8, the load operation of the gas turbine 2 ends.

That is, the period from t1 to t4 is the operation of the oil fuel 8b, and the period from t4 to t8 is the operation of the gas fuel 8a.

As shown in FIG. 2B, the recovered water circulation water valve 34 is closed from t1 to t4 and opened from t4 to t8.

As shown in FIG. 2C, the recovered water storage tank valve 33 is opened from t1 to t5 and closed from t5 to t8.

In the first embodiment, the oil fuel 8b is used between t1 and t4. Generally, when oil fuel 8b is used, impurities that damage constituent equipment such as the gas turbine 2 may be generated. Therefore, during t1 to t4, water recovery operation and watering operation are performed. Without executing, the recovered water 15 is stored in the recovered water storage tank 31.

On the other hand, the gas fuel 8a is used between t4 and t8. In general, since the gas fuel 8a is a relatively clean gas fuel, it is unlikely that impurities that damage constituent equipment such as the gas turbine 2 will be generated. Therefore, the water recovery operation and the watering operation are executed from t5 to t8.

During the period from t4 to t5, impurities may be attached to the filling 22 with which the exhaust gas 14 is in contact. Therefore, an operation of removing the impurities adhering to the filling 22 is executed. That is, from t4 to t5, the recovered water storage tank valve 33 and the recovered water circulation water valve 34 are opened. Then, from t4 to t5, the circulating water storage tank inlet valve 35 is closed. That is, from t4 to t5, the watering operation is executed, but the water recovery operation is not executed.

Further, from t4 to t5, the water quality of the recovered water 15 is equal to or less than the permissible value, but the water recovery operation is not executed until the predetermined value is lower than the permissible value. That is, the time until the predetermined value falls below the permissible value is a fixed time. The predetermined value is set in advance according to the power generation system. Further, from t4 to t5, the ratio of the recovered water 15 supplied to the recovered water storage tank 31 and the recovered water 15 supplied to the circulating water cooler 24 is appropriately set according to the power generation system.

From t1 to t4, the circulating water 18 is not supplied to the watering device 21, the watering device 21 does not sprinkle the filling 22, and the filling 22 is not cooled. Since the filler 22 is in a heated state above the water dew point, gas-liquid separation is not performed even if the exhaust gas 14 comes into contact with the filler 22. That is, the exhaust gas 14 is not gas-liquid separated and is discharged to the atmosphere as the exhaust gas 19. Therefore, the possibility that impurities are mixed in the recovered water 15 is small.

Further, since the recovered water circulation water valve 34 and the water storage tank inlet valve 35 are closed between t1 and t4, when impurities are mixed in the recovered water 15 due to an unexpected event corresponding to the diversification of fuel. Even so, the recovered water 15 containing impurities does not circulate in the constituent equipment such as the gas turbine 2.

Further, when the oil fuel 8b is switched to the gas fuel 8a and the gas fuel 8a is used, the concentration of impurities contained in the exhaust gas 14 decreases. Then, depending on the operating conditions of the power generation system, the amount of recovered water 15 may increase and surplus recovered water may be generated. In this case, the recovered surplus water is discharged to the outside of the system from the pipe 27 connected to the circulating water storage tank 25.

Even when the water quality of the recovered water 15 is less than the permissible value, the recovered surplus water contains some impurities. Therefore, by discharging the recovered surplus water from the pipe 27 to the outside of the system, it is possible to reduce the concentration of impurities contained in the recovered water 15 when operating with the oil fuel 8b.

Further, in the first embodiment, when the water quality of the recovered water 15 exceeds the permissible value, the recovered water 15 is stored in the recovered water storage tank 31.

Then, when the recovered surplus water is generated, first, the recovered water 15 stored in the recovered water storage tank 31 whose water quality of the recovered water 15 exceeds the permissible value is appropriately treated for environmental pollution. Then, the recovered water is discharged to the outside of the system through the pipe 46, and then the recovered surplus water whose quality of the recovered water 15 is equal to or lower than the permissible value can be stored in the recovered water storage tank 31. As a result, the concentration of impurities contained in the recovered water 15 stored in the recovered water storage tank 31 can be reduced.

Further, in the first embodiment, depending on the operating conditions of the power generation system, the recovered water 15 may be less than the water supply 17 supplied to the exhaust heat recovery boiler 11. In this case, the recovered surplus water stored in the recovered water storage tank 31 and whose water quality of the recovered water 15 is equal to or lower than the permissible value is supplied to the water recovery device 20 by the pump 37 via the pipe 36. As a result, it is not necessary to replenish the water supply 17 from outside the system, and the power generation cost of the power generation system can be reduced.

Further, in the first embodiment, since the water quality inspection device 30 for inspecting the water quality of the recovered water 15 is installed, the recovered water 15 is caused by an unexpected event corresponding to the diversification of the fuel even during the operation of the gas fuel 8a. Even when impurities are mixed in the gas turbine 2, the recovered water 15 in which the impurities are mixed does not circulate in the constituent equipment such as the gas turbine 2, and the corresponding processing can be promptly executed. It is possible to ensure the mechanical reliability of the constituent devices such as.

Further, in the first embodiment, the case where the exhaust gas 14 contains impurities during the operation of the oil fuel 8b has been described.

However, some oil fuels are relatively clean oil fuels (for example, biofuels) whose use has not been considered in the past, and whether or not such oil fuels contain impurities in the exhaust gas 14. , There are also unknown oil fuels. Even in such a case, since the water quality inspection device 30 can be installed and the water quality of the recovered water 15 can be monitored, the options of the fuel that can be used for the combustor 3 are expanded.

As described above, in the high-humidity air-utilizing power generation system described in the first embodiment, by monitoring the water quality of the recovered water 15, the options of the fuel that can be used for the combustor 3 are expanded, and the gas turbine 2 is expanded. It is possible to ensure the mechanical reliability of the constituent devices such as.

Then, according to the first embodiment, the range of usable fuels is expanded without being limited to the relatively clean gas fuel 8a such as liquefied natural gas as the fuel, and for example, the oil fuel 8b is also used. It is possible to respond to the diversification of fuels including.

In the first embodiment, the relatively clean gas fuel 8a and the oil fuel 8b are switched and used. For example, instead of the oil fuel 8b, a gas fuel secondarily produced in another plant is used. You can also do it. That is, it is possible to switch between the relatively clean gas fuel 8a and the gas fuel produced as a by-product.

Next, a schematic configuration of the water recovery device of the high-humidity air-based power generation system described in Example 2 will be described.

FIG. 3 is an explanatory diagram illustrating a schematic configuration of a water recovery device of the high humidity air utilization power generation system described in the second embodiment.

Compared with the high-humidity air-utilizing power generation system described in Example 1, the high-humidity air-utilizing power generation system described in the second embodiment further includes an intermediate water storage tank 40, a pipe 41, an intermediate reclaimed water pump 42, and an intermediate. It has a recovery water valve 43 and a pipe 44.

In the high-humidity air-utilizing power generation system described in the second embodiment, an intermediate water storage tank 40 for storing the recovered water 45 is installed inside the water recovery device 20.

When the oil fuel 8b is supplied to the combustor 3 as fuel, the exhaust gas 14 may contain impurities that damage constituent equipment such as the gas turbine 2 depending on the type of the oil fuel 8b.

The exhaust gas 14 containing impurities is supplied to the water recovery device 20 and comes into contact with the filler 22 installed inside the water recovery device 20 to achieve gas-liquid separation. The separated gas component is discharged to the atmosphere as exhaust gas 19, the separated liquid component is liquefied, and the separated liquid component falls as recovered water 45 in the direction of gravity action.

Then, the recovered water 45 in which the exhaust gas 14 is liquefied is stored in the intermediate water storage tank 40 installed inside the water recovery device 20.

A pipe 41 is connected to the bottom of the intermediate water storage tank 40, and the pipe 41 is connected to the branch pipe 32. The pipe 41 is connected to the downstream (backflow) side of the recovered water storage tank valve 33 installed in the branch pipe 32.

As a result, the recovered water 45 stored in the intermediate water storage tank 40 is supplied to the recovered water storage tank 31 via the pipe 41 and the branch pipe 32. Further, the intermediate recovery water pump 42 and the intermediate recovery water valve 43 are installed in the pipe 41.

As described above, the high-humidity air-utilizing power generation system described in the second embodiment contains impurities generated inside the water recovery device 20, and the recovered water 45 stored in the intermediate water tank 40 is mixed with the recovered water 15. It is possible to discharge the water to the outside of the water recovery device 20 without doing so.

Further, a pipe 44 that branches from the pipe 41 and supplies the recovered water 45 stored in the intermediate water storage tank 40 to the water quality inspection device 30 is installed.

That is, in the second embodiment, the water quality inspection device 30 determines whether or not the quality of the recovered water 45 stored in the intermediate water tank 40 exceeds the permissible value, that is, the recovery stored in the intermediate water tank 40. It is possible to monitor whether or not impurities are generated in the water 45 in excess of the permissible value.

Next, an operation method of the high-humidity air-based power generation system described in the second embodiment will be described.

FIG. 4 is an explanatory diagram illustrating an operation method of the high humidity air utilization power generation system described in the second embodiment.

Here, in particular, the gas turbine 2 is operated from the start to the low load state with the oil fuel 8b, the oil fuel 8b is switched to the gas fuel 8a in the low load state, and the rated load state is operated with the gas fuel 8a. The operation method of the high-humidity air-based power generation system will be explained.

FIG. 4A is a schematic diagram simply showing the generator output (output of the generator 5) in the operation method of switching from the oil fuel 8b to the gas fuel 8a.

FIG. 4B is a schematic diagram simply showing the output of the water quality inspection device (output of the water quality inspection device 30).

FIG. 4C is a schematic view simply showing the open state of the intermediate reclaimed water valve 43.

FIG. 4D is a schematic view simply showing the open state of the recovered water circulation water valve 34.

FIG. 4 (e) is a schematic view simply showing an open state of the circulating water storage tank inlet valve 35.

As shown in FIG. 4A, the output of the generator 5 is T1, the load operation of the gas turbine 2 is started by the oil fuel 8b, the load operation of the gas turbine 2 is reached by the oil fuel 8b at T2, and the constant load is reached. At T3, the oil fuel 8b is switched to the gas fuel 8a, at T4, the load increase of the gas turbine 2 is started at the gas fuel 8a, and at T5, the rated load state is reached at the gas fuel 8a and is constant. It is operated with a load, and at T6, the load drop starts from the rated load state, and at T7, the load operation of the gas turbine 2 ends. That is, the period from T1 to T3 is the operation of the oil fuel 8b, and the period from T3 to T7 is the operation of the gas fuel 8a.

Note that T1 is the timing of starting (parallel) the gas turbine 2 in the oil fuel 8b, T2 is the timing of reaching the low load state in the oil fuel 8b, and T3 is the timing from the oil fuel 8b to the gas fuel 8a in the low load state. The switching timing, T4 is the timing when a certain time elapses after switching from the oil fuel 8b to the gas fuel 8a, T5 is the timing when the gas fuel 8a reaches the rated load state, and T6 is the load drop from the rated load state. The start timing and T7 indicate the stop (disconnection) timing of the gas turbine 2, respectively.

As shown in FIG. 4B, the output of the water quality inspection device 30 rises at T1, shows a peak value between T2 and T3, and then falls. Then, the water quality tolerance value (the water quality tolerance value of the recovered water 45 stored in the intermediate water tank 40) is exceeded (exceeded) between T1 and T2, and is below the water quality tolerance value between T3 and T4.

In this way, at T3, the oil fuel 8b is switched to the gas fuel 8a, and the concentration of impurities contained in the exhaust gas 14 decreases. Therefore, the concentration of impurities contained in the recovered water 45 stored in the intermediate recovery tank 40 also increases. It decreases, and the output of the water quality inspection device 30 also decreases.

As shown in FIG. 4C, in the intermediate recovery water operation (operation of supplying the recovery water 45 stored in the intermediate water storage tank 40 to the recovery water storage tank 31: operation of driving the intermediate recovery water pump 42), The intermediate recovery water valve 43 is opened from the middle of T1 and T2 to T4, and closed from the middle of T1 to T1 and T2, and from T4 to T7. That is, at the timing when the reclaimed water 45 is stored in the reclaimed water tank 40 (in the middle of T1 and T2), the reclaimed water pump 42 is activated and the reclaimed water valve 43 is opened. Then, at the timing (T4) when a certain time elapses after the oil fuel 8b is switched to the gas fuel 8a, the intermediate recovery water pump 42 is stopped and the intermediate recovery water valve 43 is closed.

In this way, at T3, the oil fuel 8b is switched to the gas fuel 8a, and the water quality inspection device 30 confirms that the water quality of the recovered water 45 stored in the intermediate water tank 40 is equal to or less than the permissible value (T4). Then, the intermediate recovery water valve 43 is closed.

As shown in FIG. 4D, in the sprinkling operation, the recovered water circulation water valve 34 is opened from T1 to T7.

As shown in FIG. 4 (e), in the humidification operation, the circulating water storage tank inlet valve 35 is opened from T1 to T7.

The recovered water storage tank valve 33 is closed from T1 to T7.

As described above, in the second embodiment, the recovered water circulation water valve 34 and the circulation water storage tank inlet valve 35 are opened during T1 to T7, and the watering operation and the humidification operation are executed.

That is, in the second embodiment, the circulating water pump 23 is started, the recovered water circulating water valve 34 is opened, and the recovered water 15 is sprinkled from the timing (T1) when the load operation of the gas turbine 2 is started with the oil fuel 8b. Water is sprinkled from 21 to the filling 22 to execute the sprinkling operation, the circulating water storage tank inlet valve 35 is opened, the recovered water 15 is supplied to the exhaust heat recovery boiler 11, and the humidification operation is executed.

In the second embodiment, the watering operation and the humidifying operation are also executed during the operation of the oil fuel 8b. Therefore, the output of the gas turbine 2 increases. On the other hand, since the circulating water 18 used for the watering operation and the water supply 17 used for the humidifying operation are the recovered water 15, in the second embodiment, depending on the conditions of the time of the watering operation or the humidifying operation and the flow rate of the recovered water 15. , It is necessary to supply the circulating water 18 and the water supply 17 from outside the system.

Further, when the intermediate recovery water valve 43 is closed at T4, the recovered water 45 stored in the intermediate water storage tank 40 increases, overflows the intermediate water storage tank 40, and mixes with the recovered water 15. However, since the water quality of the reclaimed water 45 overflowing the intermediate water storage tank 40 is equal to or less than the permissible value, even if the reclaimed water 45 is mixed with the reclaimed water 15, the water quality of the reclaimed water 15 does not deteriorate.

As described above, in the second embodiment, during the operation of the oil fuel 8b, the recovered water 45 exceeding the water quality allowable value is discharged to the outside of the water recovery device 20 without being mixed with the recovered water 15, and the gas fuel 8a is operated. At this time, the recovered water 45, which is below the allowable water quality, is mixed with the recovered water 15.

Further, according to the second embodiment, the concentration of impurities contained in the recovered water 15 can be reduced without mixing the recovered water 45 exceeding the allowable water quality with the recovered water 15. In addition, the flow rate of the recovered water 15 containing impurities does not increase. That is, the water quality of the recovered water 15 is not more than the permissible value, and the flow rate of the recovered water 15 containing impurities can also be reduced.

As described above, in the high-humidity air-utilizing power generation system described in Example 2, the options of fuels that can be used for the combustor 3 are expanded by monitoring the water quality of the recovered water 15 and the water quality of the recovered water 45. At the same time, the mechanical reliability of the constituent equipment such as the gas turbine 2 can be ensured.

The present invention is not limited to the above-described examples, and includes various modifications. For example, the above-described embodiment has been specifically described in order to explain the present invention in an easy-to-understand manner, and is not necessarily limited to those having all the described configurations. In addition, a part of the configuration of one embodiment can be replaced with a part of the configuration of another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. Further, it is possible to add, delete, or replace a part of the other configurations with respect to a part of the configurations of each embodiment.

1 ... Pump, 2 ... Gas turbine, 3 ... Combustor, 4 ... Starter, 5 ... Generator, 6 ... Air, 7 ... Compressed air, 8a ... Gas fuel, 8b ... Oil fuel, 9 ... Combustion gas, 10 ... Exhaust gas, 11 ... Exhaust heat recovery boiler, 12 ... Steam, 13 ... Steam generator, 14 ... Exhaust gas, 15 ... Recovery water, 16 ... Cooling water, 17 ... Water supply, 18 ... Circulating water, 19 ... Exhaust gas, 20 ... Water recovery device, 21 ... Sprinkler, 22 ... Filling, 23 ... Circulating water pump, 24 ... Circulating water cooler, 25 ... Circulating water storage tank, 26 ... Water supply pump, 27 ... Piping, 30 ... Water quality inspection device , 31 ... Recovery water storage tank, 32 ... Branch pipe, 33 ... Recovery water storage tank valve, 34 ... Recovery water circulation water valve, 35 ... Circulation water storage tank inlet valve, 36 ... Piping, 37 ... Pump, 40 ... Intermediate water storage tank , 41 ... Piping, 42 ... Intermediate recovery water pump, 43 ... Intermediate recovery water valve, 44 ... Piping, 45 ... Recovery water, 46 ... Piping.

Claims (8)

From a gas turbine driven by using combustion gas supplied from a combustor, an exhaust heat recovery boiler that generates steam using the exhaust gas discharged from the gas turbine as a heat source, and an exhaust gas discharged by the exhaust heat recovery boiler. A high-humidity air-utilizing power generation system having a water recovery device for recovering water and supplying the steam generated by the exhaust heat recovery boiler to the combustor.
It has a water quality inspection device for inspecting the quality of the recovered water collected by the water recovery device, and a recovery water storage tank for storing the recovered water according to the water quality conditions of the recovered water inspected by the water quality inspection device. A high-humidity air-based power generation system featuring. The high-humidity air-based power generation system according to claim 1.
The water recovery device is characterized by having a filler for gas-liquid separation of the exhaust gas discharged from the exhaust heat recovery boiler and an intermediate water storage tank for storing the recovered water falling from the filler. Moisture air power generation system. The high-humidity air-based power generation system according to claim 2.
The water quality inspection device is a high-humidity air-utilizing power generation system characterized in that it inspects the quality of the recovered water stored in the intermediate water storage tank. The high-humidity air-based power generation system according to claim 1.
It has a pipe for supplying the recovered water collected by the water recovery device to the watering device installed inside the water recovery device, and a branch pipe for branching from the pipe and supplying the recovered water to the recovered water storage tank. A high-humidity air-based power generation system featuring. The high-humidity air-based power generation system according to claim 4.
A high-humidity air-utilizing power generation system characterized in that a recovered water circulation water valve is installed in the pipe and a recovered water storage tank valve is installed in the branch pipe. A gas turbine is driven using the combustion gas supplied from the combustor, steam is generated by an exhaust heat recovery boiler using the exhaust gas discharged from the gas turbine as a heat source, and a water recovery device is used from the exhaust gas. It is an operation method of a high-humidity air-utilizing power generation system that recovers water in the above and supplies the steam generated by the exhaust heat recovery boiler to the combustor.
The quality of the recovered water collected by the water recovery device is inspected by the water quality inspection device, and the recovered water is stored in the recovery water storage tank according to the water quality conditions of the recovered water inspected by the water quality inspection device. How to operate a high-humidity air-based power generation system. The method of operating the high-humidity air-based power generation system according to claim 6.
A method for operating a high-humidity air-utilizing power generation system, which comprises storing the recovered water in a recovered water storage tank when the quality of the recovered water exceeds an allowable value. The method of operating the high-humidity air-based power generation system according to claim 7.
A method for operating a high-humidity air-utilizing power generation system, which comprises performing a sprinkling operation and a humidifying operation when the quality of the recovered water is equal to or less than an allowable value.

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