JP2009085540A - Steam generation device and steam generation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a steam generation device capable of reducing a supply cost of superheated steam and suppressing an increase in environmental load. <P>SOLUTION: The steam generation device is provided with a turbo compressor 2 for compressing a refrigerant R134a to a supercritical state, a steam generating part 3 for generating superheated steam by performing heat exchange with the R134a in the supercritical state, a high pressure side decompression part 4H for reducing pressure of the R134a that flowed out of the steam generation part 3, an intermediate part 5 for separating the R134a decompressed by the high pressure side decompression part 4H into a gaseous phase and a liquid phase, and supplying the R134a in the gaseous phase to the turbo compressor 2 in the middle of the compression process, a low pressure side decompression part 4L for further reducing the pressure of the R134a in the liquid phase flowing out of the intermediate part 5, and an evaporator 7 for evaporating the R134a in the liquid phase decompressed by the low pressure side decompression part 4L and supplying the evaporated R134a to the turbo compressor 2. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a steam generation apparatus and a steam generation method using a heat pump suitable for supplying steam.

In recent years, it has become common to use a heat pump as a cooling or heating means in an air conditioner, a hot water supply facility, or the like. As heat pumps, those using a vapor compression cycle and those using a supercritical cycle using carbon dioxide as a refrigerant are known (for example, see Patent Document 1).
Thus, by using a heat pump as the heating means, it is possible to reduce the amount of carbon dioxide emission compared to the conventional method of supplying heat by burning oil or gas.

On the other hand, in order to supply steam, a once-through steam boiler that generates steam by using combustion heat of oil or gas is generally used. In the case of supplying steam, it is supplied as superheated steam, for example, 120 ° C superheated steam, for preventing steam liquefaction.
Japanese Patent Publication No. 7-18602

In the case of a heat pump using a vapor compression cycle, the heat exchanger that exchanges heat with water transitions from the superheated steam region of the refrigerant on the high-pressure side to the gas-liquid two-phase region, and exchanges heat with the refrigerant mainly through condensation heat transfer. Is used to generate superheated steam.
When superheated steam is generated, since the temperature of superheated steam is higher than that of hot water, the saturation temperature required for the refrigerant in the high-pressure side gas-liquid gas-liquid two-phase region also increases, and the high-pressure side gas-liquid gas-liquid The saturation pressure of the refrigerant in the phase region also increases. For this reason, high pressure resistance is required for the heat exchanger that performs heat exchange between the refrigerant and the steam, and the apparatus becomes expensive, so that there is a problem that the supply cost of the superheated steam increases.

  In the case of a supercritical cycle heat pump that uses carbon dioxide as the refrigerant, the supercritical refrigerant pressure at the temperature required to generate superheated steam is high, so the heat exchanger that generates superheated steam by heat exchange is high. Pressure resistance is required. Then, there was a problem that the heat exchanger becomes expensive and the entire apparatus becomes expensive.

On the other hand, when steam is supplied using a once-through steam boiler or the like, there is a problem that the efficiency of the boiler is as low as 1 or less compared to the case where a heat pump is used, and superheated steam cannot be supplied efficiently.
Furthermore, the exhaust gas discharged by the combustion of oil or gas contains carbon dioxide, which has a problem of high environmental load.

  The present invention has been made to solve the above-described problem, and an object of the present invention is to provide a steam generator capable of reducing the supply cost of superheated steam and suppressing an increase in environmental load. .

In order to achieve the above object, the present invention provides the following means.
The steam generator of the present invention includes a turbo compressor that compresses R134a, which is a refrigerant, into a supercritical state, a steam generation unit that generates superheated steam by exchanging heat between the supercritical state R134a, and the steam A high-pressure side decompression unit that decompresses the pressure of R134a that has flowed out of the generation unit; and R134a decompressed by the high-pressure side decompression unit is separated into a gas phase and a liquid phase; The intermediate portion supplied in the middle, the low pressure side pressure reducing portion for further reducing the pressure of the liquid phase R134a flowing out from the intermediate portion, and the liquid phase R134a reduced by the low pressure side pressure reducing portion were evaporated and evaporated. And an evaporator for supplying R134a to the turbo compressor.

  According to the present invention, by using R134a (HFC134a) having a critical point temperature near 100 ° C. as a refrigerant, superheated steam can be efficiently generated using R134a in a supercritical state. That is, the temperature of R134a in the supercritical state can be easily set to a temperature suitable for generating superheated steam by heating water, specifically, a temperature several tens of degrees higher than the temperature of the generated superheated steam. And superheated steam can be generated efficiently.

  On the other hand, the pressure of R134a in the supercritical state at the above-described temperature is about 4 MPa, and the pressure of R134a supplied to the steam generation unit is lower than that in the supercritical cycle using carbon dioxide. Therefore, the pressure resistance required for the steam generation unit is reduced, and an inexpensive heat exchanger can be used as compared with a heat exchanger used in a supercritical cycle using carbon dioxide. That is, since the manufacturing cost of a steam generation part can be suppressed, the supply cost of superheated steam can be suppressed.

Since the superheated steam is generated by the heat pump using R134a as the refrigerant, the generation efficiency of the superheated steam is higher than that of the superheated steam using a boiler such as a once-through boiler. Moreover, compared with the case where a boiler is used, the quantity of the carbon dioxide released when producing | generating superheated steam decreases.
Furthermore, the amount of carbon dioxide released when superheated steam is generated can be further reduced by driving the turbo compressor with system power that emits less carbon dioxide.

  In the above invention, it is desirable that the steam generating unit is provided with a feed water pump for supplying water for generating superheated steam, and the supply of superheated steam is controlled by the feed water pump.

  According to the present invention, the supply of water to the steam generation unit is controlled by controlling the operation of the feed water pump. When the supply of water to the steam generation unit is controlled, the generation of superheated steam in the steam generation unit is also controlled, so the supply of superheated steam is controlled.

For example, the heat pump compressor is controlled to adjust the heat amount of R134a with respect to the required steam amount. However, in order to keep the output steam in the overheated region of the specification, adjustment of R134a is not sufficient, and the amount of water in the feed pump is appropriately adjusted. That is, when the temperature of the superheated steam is lowered, the amount of water supplied to the steam generating unit is reduced according to the temperature of the superheated steam, the temperature of the superheated steam is kept at a predetermined temperature, and the amount of supplied superheated steam is reduced.
On the other hand, when the temperature of the superheated steam rises, the amount of water supplied to the steam generator is increased in accordance with the temperature of the superheated steam, the temperature of the superheated steam is kept at a predetermined temperature, and the amount of supplied superheated steam is increased.

  In the above-mentioned invention, it is desirable that an intermediate heat exchanging section for exchanging heat between R134a in the liquid phase flowing out from the intermediate section and R134a evaporated in the evaporating section is provided.

  According to the present invention, by performing heat exchange between the liquid phase R134a flowing out from the relatively high temperature intermediate portion and the R134a evaporated in the relatively low temperature evaporation portion, the turbo compressor can be The temperature of R134a to be inhaled can be increased. When the intake refrigerant temperature in the turbo compressor rises, the discharged refrigerant temperature also rises, so that the temperature of the supercritical state R134a supplied to the steam generation unit can be increased.

  In the above invention, the intermediate part is provided with a liquid level detecting part for detecting the position of the liquid level of R134a, and the low pressure side pressure reducing part is controlled based on the detection result of the liquid level detecting part. Is desirable.

According to the present invention, since the low pressure side pressure reducing unit can control the flow rate of R134a flowing out from the intermediate part, the liquid level of R134a in the intermediate part is controlled by being controlled based on the detection result of the liquid level detecting part. Can be controlled. In other words, the liquid phase R134a can be controlled to be always present in the intermediate portion, and the liquid phase R134a can be stably supplied to the intermediate heat exchanger.
Therefore, the flow rate of R134a supplied from the intermediate part to the intermediate heat exchanger can be stabilized, and the temperature of R134a sucked into the turbo compressor can be stabilized.

  In the above invention, a bypass flow path for guiding a part of R134a supplied to the intermediate heat exchange section between the low pressure side decompression section and the evaporation section, and a flow rate of R134a flowing through the bypass flow path are controlled. And a suction temperature detection unit that detects the temperature of R134a sucked into the turbo compressor, and the flow rate of R134a flowing through the bypass control unit depends on the detection result of the suction temperature detection unit. It is desirable that the flow rate of R134a flowing through the low pressure side pressure reducing unit is controlled based on the flow rate of R134a flowing through the bypass flow path.

According to the present invention, by controlling the flow rate of R134a flowing through the bypass flow path, the flow rate of the liquid phase R134a flowing into the intermediate heat exchanger is controlled. Therefore, the amount of heat exchanged in the intermediate heat exchanger is controlled, and the temperature of R134a sucked into the turbo compressor is controlled.
That is, the temperature of R134a sucked into the turbo compressor can be controlled by controlling the bypass control unit based on the detection result of the suction temperature detection unit.

On the other hand, by controlling the flow rate of R134a flowing through the low pressure side decompression unit, the flow rate of R134a in the liquid phase flowing out from the intermediate unit is controlled. Therefore, the liquid level of R134a can be held in the intermediate portion, and the liquid phase R134a can be stably supplied to the intermediate heat exchanger.
That is, by controlling the flow rate of R134a flowing through the low pressure side decompression unit based on the flow rate of R134a flowing through the bypass flow path, the liquid phase R134a can be stably supplied to the intermediate heat exchanger. Thereby, the temperature of R134a sucked into the turbo compressor can be stably controlled.

  In the said invention, it is desirable to provide the intermediate heat exchange part which performs heat exchange between R134a which flowed out from the said steam production | generation part, and R134a evaporated in the said evaporation part.

  According to the present invention, by performing heat exchange between the R134a in the liquid phase flowing out from the steam generation section having a relatively high temperature and the R134a evaporated in the evaporation section having a relatively low temperature, the turbo compressor The temperature of R134a sucked in can be increased. When the intake refrigerant temperature in the turbo compressor rises, the discharged refrigerant temperature also rises, so that the temperature of the supercritical state R134a supplied to the steam generation unit can be increased.

  In the above-described invention, a part of R134a supplied to the intermediate heat exchange part is led between the high-pressure side pressure reducing part and the intermediate part, and the flow rate of R134a flowing through the bypass channel is controlled. And a bypass temperature detection unit that detects the temperature of R134a sucked into the turbo compressor, and the bypass control unit is controlled based on the detection result of the suction temperature detection unit, The high pressure side decompression unit is preferably controlled based on the flow rate of R134a flowing through the bypass flow path.

According to the present invention, by controlling the flow rate of R134a flowing through the bypass flow path, the flow rate of the liquid phase R134a flowing into the intermediate heat exchanger is controlled. Therefore, the amount of heat exchanged in the intermediate heat exchanger is controlled, and the temperature of R134a sucked into the turbo compressor is controlled.
That is, the temperature of R134a sucked into the turbo compressor can be controlled by controlling the bypass control unit based on the detection result of the suction temperature detection unit.

On the other hand, by controlling the flow rate of R134a flowing through the high pressure side decompression unit, the flow rate of the liquid phase R134a flowing out from the steam generation unit is controlled, and the temperature of R134a flowing out can be controlled.
That is, by controlling the flow rate of R134a flowing through the high pressure side decompression unit based on the flow rate of R134a flowing through the bypass flow path, the temperature of R134a flowing out from the steam generation unit can be stabilized. Thereby, the temperature of R134a sucked into the turbo compressor can be stably controlled.

  The steam generation method of the present invention includes a compression step of compressing R134a, which is a refrigerant, into a supercritical state, a steam generation step of generating superheated steam by heat exchange with the supercritical state R134a, and the R134a after the heat exchange. A high pressure side pressure reducing step for reducing the pressure, an intermediate step for supplying the gas phase R134a in the middle of the compression step among the reduced pressure R134a separated into the gas phase and the liquid phase, and a liquid in the separated R134a A low-pressure side pressure reducing step for further reducing the pressure of the phase R134a, and an evaporation step for evaporating the pressure-reduced liquid phase R134a and supplying the evaporated R134a to the compression step. And

  According to the present invention, by using R134a (HFC134a) having a critical point temperature near 100 ° C. as a refrigerant, superheated steam can be efficiently generated using R134a in a supercritical state.

  On the other hand, the pressure of R134a in the supercritical state at the above-described temperature is lower than the pressure of R134a supplied to the steam generation process compared to the supercritical cycle using carbon dioxide, and the heat exchanger used in the steam generation process Since the manufacturing cost of can be suppressed, the supply cost of superheated steam can be suppressed.

  Since the superheated steam is generated by the heat pump using R134a as the refrigerant, the generation efficiency of the superheated steam is higher than that of the superheated steam using a boiler such as a once-through boiler. Moreover, compared with the case where a boiler is used, the quantity of the carbon dioxide released when producing | generating superheated steam decreases.

According to the steam generator of the present invention, the superheated steam can be efficiently generated by using R134a (HFC134a) having a critical point temperature near 100 ° C. as a refrigerant, and the supply cost of the superheated steam can be suppressed. There is an effect that can be. Furthermore, since the pressure of R134a in the supercritical state at the above-described temperature is about 4 MPa, there is an effect that the supply cost of the superheated steam can be suppressed.
Since superheated steam is generated by a heat pump using R134a as a refrigerant, the amount of carbon dioxide released when generating superheated steam is reduced compared with the case where a boiler is used, thereby suppressing an increase in environmental load. There is an effect that can be.

[First Embodiment]
Hereinafter, a first embodiment of the present invention will be described with reference to FIGS. 1 and 2.
FIG. 1 is a schematic diagram for explaining the outline of the steam generator according to the present embodiment.
The steam generator 1 of this embodiment supplies superheated steam using a supercritical cycle heat pump using R134a (HFC134a) as a refrigerant as a heat source. As the supercritical cycle, a supercritical cycle that performs two-stage compression and two-stage expansion is used.

  As shown in FIG. 1, the steam generator 1 includes a turbo compressor 2, a steam generation unit 3, a high-pressure expansion valve (high-pressure side decompression unit) 4 </ b> H, an intermediate cooling unit (intermediate unit) 5, and a low-pressure expansion. A valve (low pressure side expansion section) 4L and an evaporation section 7 are provided, and a heat pump through which R134a flows is configured in this order, and superheated steam is generated by the steam generation section 3 described above.

The turbo compressor 2 is a compressor that sucks low-pressure R134a from the evaporator 51 and compresses it to high-pressure (HP), and then discharges the supercritical R134a to the steam generator 23.
The turbo compressor 2 rotationally drives the inlet vane portion 11 that controls the flow rate of the sucked gas phase R134a, the low-pressure impeller 12L and the high-pressure impeller 12H that compress the sucked R134a, and both impellers 12L and 12H. A motor 13 and an inverter unit 14 are provided.

The inlet vane portion 11 is disposed upstream of the low pressure impeller 12L, and controls the flow rate of the gas-phase R134a flowing into the low pressure impeller 12L.
The low-pressure impeller 12L sucks low-pressure R134a from the evaporator 51 and raises it to an intermediate pressure (MP). The low pressure impeller 12L is disposed between the inlet vane portion 11 and the high pressure impeller 12H and is rotatably supported by the motor 13.
The high-pressure impeller 12H sucks the intermediate pressure R134a from the low-pressure impeller 12L and the intermediate cooling unit 5 and boosts it to a high pressure. The high-pressure impeller 12H is disposed on the downstream side of the low-pressure impeller 12L, and is rotatably supported by the motor 13 similarly to the low-pressure impeller 12L.

The motor 13 is connected to the high-pressure impeller 12H and the low-pressure impeller 12L via the rotating shaft 15, and rotationally drives both the impellers 12H and 12L. In the present embodiment, the motor 13 will be described when applied to a sealed motor.
Electric power is supplied to the motor 13 from the inverter unit 14, and the rotation speed is controlled.
The inverter unit 14 controls the number of revolutions of the motor 13 by controlling the power supplied to the motor 13. System power is supplied to the inverter unit 14.

The steam generator 3 generates superheated steam by exchanging heat with the supercritical R134a compressed by the turbo compressor 2. In the present embodiment, description will be made by applying the present invention to an example in which steam or hot water condensed with steam is circulated with a steam supply target 20 to which superheated steam is supplied.
The steam generation unit 3 is provided with a feed water pump 21, a feed water temperature sensor 22, a steam generator 23, and a steam temperature sensor 24. Further, the steam generating unit 3 is provided with a water softening device (not shown) that softens hot water that generates superheated steam.

  The feed water pump 21 is a pump that is used in the steam supply target 20 and sends condensed hot water to the steam generator 23. The water supply pump 21 is provided with an inverter unit 25, and the rotation of the water supply pump 21 is controlled by the inverter unit 25.

The feed water temperature sensor 22 is disposed between the feed water pump 21 and the steam generator 23 and measures the temperature of the hot water supplied to the steam generator 23.
The steam temperature sensor 24 is disposed between the steam generator 23 and the steam supply target 20 and measures the temperature of superheated steam generated in the steam generator 23.

The steam generator 23 is a heat exchanger that performs heat exchange between the supercritical state and liquid phase R134a, hot water, and steam to generate superheated steam. The steam generator 23 is configured such that the flow direction of R134a and the flow directions of hot water and steam face each other. In other words, the piping through which the hot water and steam flow is arranged so as to enter the container of the steam generator 23 from the downstream side of the R134a flow and exit from the upstream side to the outside of the container.
The upstream side in the steam generator 23 is a region where gas-phase R134a exists in the supercritical state, and the downstream side is a region where liquid-phase R134a exists. The piping through which hot water and steam flow is arranged over both regions.

The steam generator 23 is provided with a steam generator pressure sensor 26H that measures the pressure of the internal R134a and a hot gas bypass unit 27 that bypasses the R134a in the steam generator 23 to the evaporator 51.
The hot gas bypass unit 27 is provided with a hot gas valve 28 for controlling the flow rate of R134a to be bypassed.

  The high-pressure expansion valve 4H is a pressure control valve that reduces the high-pressure R134a flowing out from the steam generator 23 to an intermediate pressure, and is disposed between the steam generator 23 and the intermediate cooling unit 5. The high-pressure expansion valve 4H controls the flow rate of R134a passing through the high-pressure expansion valve 4H based on the output of the high-pressure temperature sensor 31H that measures the temperature of R134a that has flowed out of the steam generator 23.

  The intermediate cooling unit 5 separates R134a reduced to an intermediate pressure into a gas phase and a liquid phase, supplies the gas phase R134a to the turbo compressor 2, and supplies the liquid phase R134a to the evaporation unit 7. . The intermediate cooling unit 5 is provided with a separation unit 41, a liquid level detection sensor 42, a gas supply unit 43, and a liquid supply unit 44.

The separation unit 41 is a container that separates R134a decompressed to the supplied intermediate pressure into a gas phase and a liquid phase.
The separation unit 41 is connected to a pipe to which R134 decompressed to an intermediate pressure by the high pressure expansion valve 4H is connected, and to the gas supply unit 43 and the evaporator 51 for supplying the gas phase R134a to the turbo compressor 2. A liquid supply unit 44 that supplies R134a in the liquid phase is connected.

  The liquid level detection sensor 42 is a sensor that detects the position of the liquid level of the liquid phase R134a separated in the separation unit 41. The output of the liquid level detection sensor 42 is input to the low pressure expansion valve 4L.

  The gas supply unit 43 is a pipe that supplies gas-phase R134a to the high-pressure impeller 12H of the turbo compressor 2. The gas supply unit 43 is connected to the vicinity of the upper end (upper end in FIG. 1) of the separation unit 41. In other words, the separator 41 is connected to a region where the gas phase R134a exists.

The liquid supply unit 44 is a pipe that supplies the liquid phase R134a to the evaporator 51. The liquid supply unit 44 is connected to the lower end of the separation unit 41. In other words, the separator 41 is connected to a region where the liquid phase R134a exists.
The liquid supply unit 44 is provided with an intermediate cooling unit pressure sensor 45 that measures the pressure of the liquid-phase R134a flowing inside.

  The low-pressure expansion valve 4L is a pressure regulating valve that reduces the pressure of the liquid phase R134a flowing out from the intermediate cooling unit 5 to a low pressure (LP), and is disposed between the intermediate cooling unit 5 and the evaporation unit 7. . The low pressure expansion valve 4L controls the flow rate of R134a passing through the low pressure expansion valve 4L based on the output of the liquid level detection sensor 42.

The evaporating unit 7 exchanges heat between the liquid phase R134a and the hot water supplied from the heat source 50 to evaporate R134a. In the present embodiment, description will be made by applying to an embodiment in which hot water for evaporating R134a in the liquid phase is circulated with the heat source 50.
The evaporator 7 is provided with an evaporator 51, an evaporator pressure sensor 52L, an inflow temperature sensor 53, and an outflow temperature sensor 54.

The evaporator 51 is a heat exchanger that performs heat exchange between the liquid-phase R134a and hot water to evaporate the liquid-phase R134a. The inside of the evaporator 51 has a region where the liquid phase R134a exists (lower region in FIG. 1) and a region where the gas phase R134a exists (upper region in FIG. 1), and is supplied from the heat source 50. The pipe through which the warm water flows is arranged only in the region where the liquid phase R134a exists.
The evaporation unit pressure sensor 52L is a sensor that measures the pressure of R134a inside the evaporation unit 7.

The heat source 50 is a heat source that supplies hot water that exchanges heat with the liquid phase R134a. For example, an air-cooled heat pump can be used. In the present embodiment, description will be made by applying to a chiller that receives hot water of about 50 ° C. and supplies hot water of about 55 ° C. In addition, the temperature of the hot water supplied should just be the range of about 40 degreeC to about 55 degreeC, and is not specifically limited.
The inflow temperature sensor 53 is a sensor that measures the temperature of the hot water flowing from the heat source 50 toward the evaporator 51, and the outflow temperature sensor 54 is a sensor that measures the temperature of the hot water that flows from the evaporator 51 toward the heat source 50. is there.

Next, the vapor | steam production | generation method in the steam generator 1 which consists of said structure is demonstrated.
When superheated steam is generated by the steam generator 1, a heat pump including the turbo compressor 2 and the like is operated, and the superheated steam is generated by the heat supplied from the heat pump.
Hereinafter, generation of superheated steam will be described while explaining the operation of the heat pump.

  As shown in FIG. 1, electric power is supplied to the motor 13 of the turbo compressor 2 from the inverter unit 14, and the motor 13 is driven to rotate. The rotational driving force of the motor 13 is transmitted to the low pressure impeller 12L and the high pressure impeller 12H via the rotating shaft 15, and R134a is compressed to a supercritical state (compression process).

FIG. 2 is a Mollier diagram for explaining the state change of R134a in the steam generator of FIG.
Specifically, the low-pressure impeller 12L sucks the gas-phase R134a by being rotationally driven and compresses it to an intermediate pressure (A → B in FIG. 2). The high-pressure impeller 12H sucks and compresses R134a compressed by the low-pressure impeller 12L and the gas-phase R134a supplied from the separation unit 41 to high pressure (C → in FIG. 2). D).
R134a discharged from the high-pressure impeller 12H is in a supercritical state as shown in FIG. 2, and its temperature is about 150 ° C. and the pressure is about 5 MPa.

  R134a compressed to the supercritical state by the turbo compressor 2 is supplied to the steam generation unit 3 as shown in FIG. In the steam production | generation part 3, heat exchange is performed between high temperature R134a, a steam, and warm water, and a superheated steam is produced | generated (steam production | generation process).

Specifically, about 140 ° C. R134a flowing into the steam generator 23 exchanges heat with the already evaporated steam to generate 120 ° C. superheated steam. The generated superheated steam is supplied from the steam generator 23 to the steam supply target 20.
R134a in the supercritical state flows from the upstream side to the downstream side of the steam generator 23, exchanges heat with steam and hot water, and the temperature decreases (D → E in FIG. 2). At this time, the pressure of R134a also slightly decreases due to the flow resistance of the steam generator 23 and the like.
R134a flowing in the steam generator 23 changes from the supercritical state close to the gas phase to the liquid phase in the vicinity region below the critical point temperature. Therefore, in the downstream region of the steam generator 23, the liquid phase R134a is about 95 ° C.

The superheated steam of about 120 ° C. supplied to the steam supply target 20 as described above is condensed and liquefied by being used in the steam supply target 20, and is further cooled to about 90 ° C. to be heated from the steam supply target 20. Return to the steam generator 23.
The hot water of about 90 ° C. returning to the steam generator 23 first flows into the region where the liquid phase R134a of about 100 ° C. is present, and is heat-exchanged. Thereafter, as the hot water flows toward the upstream side of the steam generator 23, the hot water is heat-exchanged with the higher-temperature R 134 a and heated to evaporate into steam. Eventually, as described above, the superheated steam at about 120 ° C. is supplied to the steam supply target 20 again.

For example, the heat pump compressor is controlled to adjust the heat amount of R134a with respect to the required steam amount. However, in order to keep the output steam in the overheated region of the specification, adjustment of R134a is not sufficient, and the amount of water in the feed pump is appropriately adjusted. That is, when the temperature of the superheated steam is lowered, the amount of water supplied to the steam generating unit is reduced according to the temperature of the superheated steam, the temperature of the superheated steam is kept at a predetermined temperature, and the amount of supplied superheated steam is reduced.
The flow rate of the hot water supplied to the steam generator 23 is controlled by the feed water pump 21 so as to supply superheated steam to the steam supply target 20.
For example, when the amount of heat of R134a in the supercritical state is insufficient with respect to the steam supply target 20 in the steam generation unit 3, the heat pump compressor 2 is controlled to increase the thermal power. However, in order to keep the output steam in the overheated region of the specification, adjustment of R134a is not sufficient, and the amount of water in the feed pump 21 is adjusted appropriately. The amount of water supplied to the steam generator 3 is reduced in accordance with the amount of heat exchanged, the temperature of the superheated steam is kept at a predetermined temperature, and the amount of superheated steam supplied to the steam supply target 20 is reduced.

On the other hand, when the amount of heat of R134a in the supercritical state with respect to the steam supply target 20 is excessive, the heat power is reduced by controlling the heat pump compressor 2. However, in order to keep the output steam in the overheated region of the specification, adjustment of R134a is not sufficient, and the amount of water in the feed pump 21 is adjusted appropriately. While maintaining the temperature of the superheated steam at a predetermined temperature, the amount of superheated steam supplied to the steam supply target 20 is increased.
The amount of heat exchanged with the supercritical state R134a in the steam generation unit 3 can be estimated from, for example, the load applied to the turbo compressor 2 and the rotation speed, and the feedwater pump 21 may be controlled from these values. .

As shown in FIG. 1, the liquid phase R134a flowing out of the steam generator 23 is reduced to an intermediate pressure by the high pressure expansion valve 4H (high pressure side pressure reducing step).
Specifically, the high-pressure R134a is reduced to an intermediate pressure by passing through the high-pressure expansion valve 4H that is a throttle valve whose opening degree can be adjusted (E → F in FIG. 2). The opening degree of the high-pressure expansion valve 4H is controlled so that the temperature becomes constant based on the temperature of R134a detected by the high-pressure temperature sensor 31H.
By controlling in this way, the position of the liquid surface of the liquid phase R134a in the steam generator 23 is kept constant.

  As shown in FIG. 1, the decompressed R134a flows into the separation unit 41 of the intermediate cooling unit 5. In the separation unit 41, R134a is separated into a gas phase and a liquid phase, and the gas phase R134a is supplied to the high-pressure impeller 12H of the turbo compressor 2 via the gas supply unit 43 (intermediate step, F in FIG. 2). → C). The gas phase R134a supplied to the high-pressure impeller 12H is compressed again by the high-pressure impeller 12H as shown in FIG. 1, and the above-described cycle is repeated.

On the other hand, the liquid-phase R134a is cooled in the separation unit 41 (F → G in FIG. 2), then flows out through the liquid supply unit 44, and is decompressed to a low pressure by the low-pressure expansion valve 4L (low-pressure side decompression). Step, G → H in FIG. Specifically, the low pressure expansion valve 4L is feedback-controlled based on the detection signal of the liquid level detection sensor 42 so that the liquid level of the liquid phase R134a in the separation unit 41 is located within a predetermined range.
As described above, the low pressure expansion valve 4L may be feedback controlled so as to keep the liquid level of the liquid phase R134a in the separation unit 41 substantially constant, or may be controlled by feedforward control based on a preset parameter. There is no particular limitation.

  The decompressed R134a flows into the evaporator 51 as shown in FIG. The liquid-phase R134a that has flowed into the evaporator 51 undergoes heat exchange with the hot water supplied from the heat source 50 to evaporate into a gas-phase R134a (evaporation step).

  Specifically, the liquid-phase R134a flows into the evaporator 51 from the vicinity of the lower end (the lower end portion in FIG. 1), and forms a region where the liquid-phase R134a exists below the evaporator 51. The liquid-phase R134a in this region is evaporated by exchanging heat with hot water of about 55 ° C. supplied from the heat source 50 to become gas-phase R134a. The gas-phase R134a flows out from the vicinity of the upper end of the evaporator 51, is sucked into the low-pressure impeller 12L of the turbo compressor 2, and repeats the above cycle.

  The hot water whose temperature has been reduced to about 50 ° C. by exchanging heat with the liquid phase R 134 a is returned from the evaporator 51 to the heat source 50. The heat source 50 heats the returned hot water of about 50 ° C. to hot water of about 55 ° C. and supplies it to the evaporator 51.

  When the operation of the steam generator 1 in the present embodiment is started, control is performed to change the time from the stop state to the steady operation state according to the temperature of the refrigerant or the like.

For example, when the stop period of the steam generator 1 is relatively long and the temperature of the refrigerant or component equipment is at room temperature (about room temperature), the time until the steady operation is longer than the hot operation described later. Cold operation is performed.
By controlling in this way, the steam generator 1 can be started safely while balancing the temperature and pressure in the steam generator 1.

On the other hand, when the operation that repeats the operation stop is performed, the stop period of the steam generator 1 is relatively short, and the temperature of the refrigerant or the like is close to the temperature at the time of the normal operation, the operation from the cold operation to the normal operation is performed. Hot operation with shorter time is performed.
By controlling in this way, the time required for starting the steam generator 1 can be shortened, and the time required for supplying superheated steam can be shortened.

  According to said structure, supercritical steam can be efficiently produced | generated using R134a of a supercritical state by using R134a (HFC134a) whose temperature of a critical point is 100 degreeC vicinity as a refrigerant | coolant. That is, the temperature of R134a in the supercritical state is set to a temperature suitable for heating water to generate superheated steam, specifically, a temperature several tens of degrees higher than the temperature of the generated superheated steam (about 120 ° C.) ( About 150 ° C.). Therefore, the steam generator 1 of this embodiment can generate | occur | produce superheated steam efficiently, and can suppress the supply cost of superheated steam.

  On the other hand, the pressure of R134a in the supercritical state at about 150 ° C. is about 4 MPa, and the pressure of R134a supplied to the steam generator 23 of the steam generation unit 3 is lower than that in the supercritical cycle using carbon dioxide. can do. Therefore, the pressure resistance required for the steam generator 23 is reduced, and an inexpensive heat exchanger can be used as compared with a heat exchanger used in a supercritical cycle using carbon dioxide. That is, since the manufacturing cost of the steam generation part 3 can be suppressed, the supply cost of superheated steam can be suppressed.

Since the steam generator 1 of the present embodiment generates superheated steam by a heat pump using R134a as a refrigerant, the generation efficiency of superheated steam is higher than that of superheated steam using a boiler such as a once-through boiler. . Moreover, compared with the case where a boiler is used, the quantity of the carbon dioxide released when producing | generating superheated steam can be decreased.
Furthermore, the amount of carbon dioxide released when superheated steam is generated can be further reduced by driving the turbo compressor 2 with system power that emits less carbon dioxide.

  By controlling the operation of the feed water pump 21, the supply of water to the steam generator 3 is controlled. When the supply of water to the steam generation unit 3 is controlled, the generation of superheated steam in the steam generation unit 3 is also controlled, so that the superheated steam having a predetermined temperature can be supplied to the steam supply target 20.

[Second Embodiment]
Next, a second embodiment of the present invention will be described with reference to FIG. 3 and FIG.
The basic configuration of the steam generator of the present embodiment is the same as that of the first embodiment, but the first embodiment is an interface that performs heat exchange between R134a of the intercooler and R134a of the evaporation unit. The difference is that a cooler is provided. Therefore, in the present embodiment, the configuration around the intercooler will be described with reference to FIGS. 3 and 4 and description of other components and the like will be omitted.
FIG. 3 is a schematic diagram for explaining the outline of the steam generator according to this embodiment.
In addition, about the component same as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 3, the steam generator 101 includes a turbo compressor 2, a steam generation unit 3, a high-pressure expansion valve 4 </ b> H, an intermediate cooling unit 5, an intermediate pressure intercooler (intermediate heat exchange unit) 110, and The low pressure expansion valve 4L and the evaporation unit 7 are provided, and a heat pump in which R134a flows in this order is configured.

The intermediate pressure intercooler 110 performs heat exchange between the liquid phase R134a flowing out from the intermediate cooling unit 5 and the R134a evaporated in the evaporation unit 7, and the temperature of the gas phase R134a sucked into the turbo compressor 2 Is set to a predetermined temperature.
The intermediate pressure intercooler 110 is provided with a heat exchange unit 111, a bypass flow path 112, and a bypass expansion valve (bypass control unit) 113.

  The heat exchange unit 111 performs heat exchange between the R134a in the liquid phase that has flowed out of the intermediate cooling unit 5 and the R134a that has evaporated in the evaporation unit 7. The heat exchanging unit 111 is arranged in a region (upper region in FIG. 3) where the gas phase R134a exists inside the evaporator 51. As the heat exchange unit 111, a liquid-gas heat exchanger, for example, a fin-and-tube heat exchanger or a laminated heat exchanger can be used.

  The bypass passage 112 and the bypass expansion valve 113 control the temperature of the gas-phase R134a sucked into the turbo compressor 2 to a predetermined temperature by controlling the flow rate of the liquid-phase R134a flowing into the heat exchange unit 111. To do.

The bypass flow path 112 is a pipe having one end connected between the intermediate cooling unit 5 and the low pressure expansion valve 4L and the other end connected between the low pressure expansion valve 4L and the evaporator 51. .
The bypass expansion valve 113 is provided in the bypass flow path 112, and controls the flow rate of the liquid phase R 134 a flowing through the bypass flow path 112. The bypass expansion valve 113 controls the flow rate of the liquid phase R134a flowing through the bypass flow path 112 based on an output signal output from the suction temperature sensor 114 that measures the temperature of the R134a sucked into the turbo compressor 2. It is.

  The low pressure expansion valve 4L controls the flow rate of R134a passing through the low pressure expansion valve 4L based on the output of the liquid level detection sensor 42 and the opening degree of the bypass expansion valve 113. In other words, the opening degree of the low pressure expansion valve 4L is controlled according to the opening degree of the bypass expansion valve 113, and controls the entire flow rate of the liquid phase R134a flowing out from the intermediate cooling section 5.

Next, a steam generation method in the steam generator 101 having the above-described configuration will be described.
FIG. 4 is a Mollier diagram for explaining the state change of R134a in the steam generator of FIG.
First, the description starts with the operation of the intermediate pressure intercooler 110, which is a feature of the present embodiment, and then the operation of the heat pump in the steam generator 101 of the present embodiment is described.

The liquid phase R134a is cooled at a predetermined temperature (for example, about 70 ° C.) in the separation unit 41, and then flows out through the liquid supply unit 44, and a part thereof is led to the heat exchange unit 111 of the intermediate pressure intercooler 110. (F → G in FIG. 4).
The liquid-phase R134a flowing into the heat exchanging section 111 exchanges heat with the R134a evaporated in the evaporator 51, and raises the temperature of the evaporated R134a (O → A1 in FIG. 4). On the other hand, the temperature of R134a in the liquid phase after heat exchange decreases (G → G1 in FIG. 4).

R134a that has flowed out of the heat exchange unit 111 is decompressed to a low pressure by the bypass expansion valve 113 (low pressure side decompression step, G1 → H1 in FIG. 4).
The bypass expansion valve 113 controls the flow rate of the liquid phase R134a flowing through the bypass flow path 112 based on the detection signal of the suction temperature sensor 114, thereby reducing the flow rate of the liquid phase R134a guided to the intermediate pressure intercooler 110. I have control. By controlling the flow rate of the liquid phase R134a guided to the intermediate pressure intercooler 110, the amount of heat exchanged in the intermediate pressure intercooler 110 is controlled, and the temperature of the gas phase R134a sucked into the turbo compressor 2 is controlled. It is controlled to a predetermined temperature, for example, about 70 ° C.

  On the other hand, the remainder of the liquid phase R134a that has flowed out of the separation unit 41 is guided to the low-pressure expansion valve 4L (F → G in FIG. 4). In the low-pressure expansion valve 4L, the liquid-phase R134a is reduced to a low pressure and flows into the evaporator 51 together with R134a that has passed through the bypass expansion valve 113 (G → H in FIG. 4). Specifically, in the low pressure expansion valve 4L, the liquid level of the liquid phase R134a in the separation unit 41 is located within a predetermined range based on the detection signal of the liquid level detection sensor 42 and the opening degree of the bypass expansion valve 113. Feedback control is performed.

R134a that has passed through the low-pressure expansion valve 4L and the bypass expansion valve 113 flows into the evaporator 51 and exchanges heat with the hot water supplied from the heat source 50, thereby evaporating to R134a in the gas phase (H → O in FIG. 4). ).
The vaporized R134a is heated to a predetermined temperature (for example, about 70 ° C.) by exchanging heat with the liquid-phase R134a flowing out from the separation section 41 as described above in the intermediate pressure intercooler 110 (FIG. 4). O → A1).

The heated R134a is sucked into the low-pressure impeller 12L of the turbo compressor 2 and is increased to an intermediate pressure (A1 → B1 in FIG. 4). R134a that has been boosted to an intermediate pressure is sucked into the high-pressure impeller 12H, boosted to a high pressure (C1 → D1 in FIG. 4), and supplied to the steam generator 3.
Since the temperature of R134a sucked into the turbo compressor 2 is raised to about 70 ° C., the temperature of R134a discharged can be easily set to about 140 ° C.
Since the subsequent cycles are the same as those in the first embodiment, description thereof is omitted.

  According to the above configuration, by performing heat exchange between the R134a in the liquid phase flowing out from the intermediate cooling unit 5 having a relatively high temperature and the R134a evaporated in the evaporation unit 7 having a relatively low temperature, The temperature of R134a sucked into the turbo compressor 2 can be increased. When the temperature of the R134a sucked into the turbo compressor 2 rises, the temperature of the discharged R134a also rises, so that the temperature of the supercritical state R134a supplied to the steam generation unit 3 can be increased.

Since the low-pressure expansion valve 4L can control the flow rate of R134a flowing out from the intermediate cooling unit 5, the low-pressure expansion valve 4L is controlled based on the detection result of the liquid level detection sensor 42 and the opening degree of the bypass expansion valve 113. The position of the liquid surface of R134a of the part 5 can be controlled. In other words, it is possible to control the intermediate cooling unit 5 so that the liquid phase R134a always exists, and the intermediate pressure intercooler 110 can be stably supplied with the liquid phase R134a.
Therefore, the flow rate of R134a supplied from the intermediate cooling unit 5 to the intermediate pressure intercooler 110 can be stabilized, and the temperature of R134a sucked into the turbo compressor 2 can be stabilized.

By controlling the flow rate of R134a flowing through the bypass passage 112, the flow rate of the liquid phase R134a flowing into the intermediate pressure intercooler 110 is controlled. Therefore, the amount of heat exchanged in the intermediate pressure intercooler 110 is controlled, and the temperature of R134a sucked into the turbo compressor 2 is controlled.
That is, by controlling the bypass expansion valve 113 based on the detection result of the suction temperature sensor 114, the temperature of R134a sucked into the turbo compressor 2 can be controlled.

On the other hand, by controlling the flow rate of R134a flowing through the low pressure expansion valve 4L, the flow rate of the liquid phase R134a flowing out from the intermediate cooling unit 5 is controlled. Therefore, the liquid level of R134a can be held in the intermediate cooling unit 5, and the liquid phase R134a can be stably supplied to the intermediate pressure intercooler 110.
That is, by controlling the flow rate of R134a flowing through the low pressure expansion valve 4L based on the flow rate of R134a flowing through the bypass flow path 112, the liquid phase R134a can be stably supplied to the intermediate pressure intercooler 110. Thereby, the temperature of R134a sucked into the turbo compressor 2 can be stably controlled.

[Third Embodiment]
Next, a third embodiment of the present invention will be described with reference to FIGS.
The basic configuration of the steam generator of the present embodiment is the same as that of the first embodiment, but the first embodiment is an interface that performs heat exchange between R134a of the steam generator and R134a of the evaporator. The difference is that a cooler is provided. Therefore, in the present embodiment, the configuration around the intercooler will be described with reference to FIGS. 5 and 6, and description of other components and the like will be omitted.
FIG. 5 is a schematic diagram for explaining the outline of the steam generator according to this embodiment.
In addition, about the component same as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 5, the steam generator 201 includes a turbo compressor 2, a steam generation unit 3, a high-pressure expansion valve 4 </ b> H, a high-pressure intercooler (intermediate heat exchange unit) 210, an intermediate cooling unit 5, A low pressure expansion valve 4L and an evaporation unit 7 are provided, and a heat pump in which R134a flows in this order is configured.

The high-pressure intercooler 210 performs heat exchange between the liquid-phase R134a that has flowed out of the steam generator 23 and the R134a that has evaporated in the evaporator 7, and the temperature of the gas-phase R134a that is sucked into the turbo compressor 2 is set. A predetermined temperature is set.
The high-pressure intercooler 210 is provided with a heat exchanging unit 211, a bypass channel 212, and a bypass expansion valve (bypass control unit) 213.

  The heat exchange unit 211 performs heat exchange between the liquid-phase R134a that has flowed out of the steam generator 23 and the R134a that has evaporated in the evaporation unit 7. The heat exchanging section 211 is arranged in a region (upper region in FIG. 5) where the gas phase R134a exists inside the evaporator 51. As the heat exchanger 211, a liquid-gas heat exchanger, for example, a fin-and-tube heat exchanger or a laminated heat exchanger can be used.

  The bypass channel 212 and the bypass expansion valve 213 control the flow rate of the liquid-phase R134a flowing into the heat exchange unit 211, thereby controlling the temperature of the gas-phase R134a sucked into the turbo compressor 2 to a predetermined temperature. To do.

The bypass passage 212 is a pipe having one end connected between the steam generator 23 and the high-pressure expansion valve 4H, and the other end connected between the high-pressure expansion valve 4H and the intermediate cooling unit 5. is there.
The bypass expansion valve 213 is provided in the bypass passage 212 and controls the flow rate of the liquid phase R134a flowing through the bypass passage 212. The bypass expansion valve 213 controls the flow rate of the liquid phase R134a flowing through the bypass passage 212 based on the output signal output from the suction temperature sensor 114 that measures the temperature of the R134a sucked into the turbo compressor 2. It is.

  The high pressure expansion valve 4H controls the flow rate of R134a passing through the high pressure expansion valve 4H based on the output of the high pressure temperature sensor 31H and the opening degree of the bypass expansion valve 213. In other words, the opening degree of the high-pressure expansion valve 4H is controlled according to the opening degree of the bypass expansion valve 213, and the high-pressure expansion valve 4H is the total flow rate of the liquid-phase R134a flowing out from the steam generator 23. The temperature is controlled.

Next, the vapor | steam production | generation method in the steam generator 201 which consists of said structure is demonstrated.
FIG. 6 is a Mollier diagram for explaining the state change of R134a in the steam generator of FIG.
First, the description starts with the action of the high-pressure intercooler 210, which is a feature of the present embodiment, and then the operation of the heat pump in the steam generator 201 of the present embodiment is described.

The liquid-phase R134a is cooled at a predetermined temperature (for example, about 100 ° C.) in the steam generator 23 and then flows out of the steam generator 23, and a part thereof is guided to the heat exchange section 211 of the high-pressure intercooler 210 ( E → E1 in FIG.
The liquid phase R134a flowing into the heat exchanging section 211 exchanges heat with the R134a evaporated in the evaporator 51, and the temperature of the evaporated R134a is raised (O → A1 in FIG. 6). On the other hand, the temperature of R134a in the liquid phase after heat exchange decreases to about 80 ° C. (E → E1 in FIG. 6).

R134a that has flowed out of the high pressure intercooler 210 is reduced to an intermediate pressure by the bypass expansion valve 213 (high pressure side pressure reducing step, E1 → F1 in FIG. 6).
On the other hand, the remainder of the liquid phase R134a flowing out of the steam generator 23 is led to the high pressure expansion valve 4H, and the liquid phase R134a is reduced to an intermediate pressure in the high pressure expansion valve 4H (E → F in FIG. 6). .

Specifically, the opening of the high pressure expansion valve 4H is determined from the steam generator 23 based on the temperature of R134a detected by the high pressure temperature sensor 31H and the opening of the bypass expansion valve 213. The temperature of the flowing out R134a is controlled to be constant.
By controlling in this way, the position of the liquid surface of the liquid phase R134a in the steam generator 23 is kept constant.
The decompressed R134a flows into the separation unit 41 together with R134a that has passed through the bypass expansion valve 213.

  In the separation unit 41, R134a is separated into a gas phase and a liquid phase, and the gas phase R134a is supplied to the high-pressure impeller 12H of the turbo compressor 2 via the gas supply unit 43 (intermediate step, F1 in FIG. 6). → F → C1). The gas phase R134a supplied to the high pressure impeller 12H is compressed again into the high pressure impeller 12H.

  On the other hand, the liquid phase R134a is cooled in the separation unit 41 (F → F1 → G in FIG. 6), then flows out through the liquid supply unit 44, and is reduced to a low pressure by the low pressure expansion valve 4L (low pressure). Side decompression step, G → H in FIG. Specifically, the low pressure expansion valve 4L is feedback-controlled based on the detection signal of the liquid level detection sensor 42 so that the liquid level of the liquid phase R134a in the separation unit 41 is located within a predetermined range.

The decompressed R134a flows into the evaporator 51 as shown in FIG. The liquid-phase R134a that has flowed into the evaporator 51 undergoes heat exchange with the hot water supplied from the heat source 50 to evaporate into a gas-phase R134a (evaporation process, H → O in FIG. 6).
The vaporized R134a is heated to a predetermined temperature (for example, about 70 ° C.) by exchanging heat with the liquid-phase R134a flowing out of the steam generator 23 as described above in the high-pressure intercooler 210 (FIG. 4). O → A1).

The heated R134a is sucked into the low-pressure impeller 12L of the turbo compressor 2 and increased to an intermediate pressure (A1 → B1 in FIG. 6). R134a that has been boosted to an intermediate pressure is sucked into the high-pressure impeller 12H, boosted to a high pressure (C1 → D1 in FIG. 6), and supplied to the steam generation unit 3.
Since the temperature of R134a sucked into the turbo compressor 2 is raised to about 70 ° C., the temperature of R134a discharged can be easily set to about 150 ° C.
Since the subsequent cycles are the same as those in the first embodiment, description thereof is omitted.

  According to the above configuration, by performing heat exchange between the R134a in the liquid phase that has flowed out of the steam generator 3 having a relatively high temperature and the R134a that has evaporated in the evaporator 7 having a relatively low temperature, The temperature of R134a sucked into the turbo compressor 2 can be increased. When the temperature of R134a sucked into the turbo compressor 2 rises, the temperature of the discharged R134a also rises, so that the temperature of the supercritical state R134a supplied to the steam generation unit 3 can be increased.

By controlling the flow rate of R134a flowing through bypass channel 212, the flow rate of liquid-phase R134a flowing into high-pressure intercooler 210 is controlled. Therefore, the amount of heat exchanged in the high-pressure intercooler 210 is controlled, and the temperature of R134a sucked into the turbo compressor 2 is controlled.
That is, by controlling the bypass expansion valve 213 based on the detection result of the high pressure temperature sensor 31H, the temperature of R134a sucked into the turbo compressor 2 can be controlled.

On the other hand, by controlling the flow rate of R134a flowing through the high-pressure expansion valve 4H, the flow rate of the liquid-phase R134a flowing out from the steam generating unit 3 is controlled, and the temperature of the flowing out R134a can be controlled.
That is, by controlling the flow rate of R134a flowing through the high-pressure expansion valve 4H based on the flow rate of R134a flowing through the bypass channel 212, the temperature of R134a flowing out from the steam generating unit 3 can be stabilized. Thereby, the temperature of R134a sucked into the turbo compressor 2 can be stably controlled.

It is a mimetic diagram explaining the outline of the steam generator concerning a 1st embodiment of the present invention. It is a Mollier diagram explaining the state change of R134a in the steam generator of FIG. It is a schematic diagram explaining the outline of the steam generator which concerns on the 2nd Embodiment of this invention. It is a Mollier diagram explaining the state change of R134a in the steam generator of FIG. It is a schematic diagram explaining the outline of the steam generator which concerns on the 3rd Embodiment of this invention. It is a Mollier diagram explaining the state change of R134a in the steam generator of FIG.

Explanation of symbols

1,101,210 Steam generator 2 Turbo compressor 3 Steam generating part 4H High pressure expansion valve (high pressure side pressure reducing part)
4L low pressure expansion valve (low pressure side expansion part)
5 Intermediate cooling part (intermediate part)
7 Evaporating section 110 Intermediate pressure intercooler (intermediate heat exchange section)
112, 212 Bypass channel 113, 213 Bypass expansion valve (bypass control unit)
210 High pressure intercooler (intermediate heat exchanger)

Claims (8)

A turbo compressor that compresses the refrigerant R134a into a supercritical state;
A steam generator that generates superheated steam by exchanging heat with R134a in a supercritical state;
A high-pressure side decompression unit that decompresses the pressure of R134a flowing out of the steam generation unit;
An intermediate portion for separating R134a decompressed by the high-pressure side decompression unit into a gas phase and a liquid phase, and supplying the gas phase R134a during the compression process of the turbo compressor;
A low-pressure side decompression section for further decompressing the pressure of the liquid phase R134a flowing out from the intermediate section;
An evaporation section for evaporating R134a in the liquid phase decompressed by the low pressure side decompression section and supplying the evaporated R134a to the turbo compressor;
The steam generator characterized by being provided. The steam generation unit is provided with a water supply pump that supplies water for generating superheated steam,
The steam generator according to claim 1, wherein supply of superheated steam is controlled by the feed water pump.   3. The steam according to claim 1, wherein an intermediate heat exchanging section is provided that exchanges heat between R134a in a liquid phase flowing out from the intermediate section and R134a evaporated in the evaporating section. Generator. The intermediate part is provided with a liquid level detection unit for detecting the position of the liquid level of R134a,
4. The steam generator according to claim 3, wherein the low-pressure side decompression unit is controlled based on a detection result of the liquid level detection unit. A bypass flow path for guiding a part of R134a supplied to the intermediate heat exchange section between the low pressure side decompression section and the evaporation section, and a bypass control section for controlling the flow rate of R134a flowing through the bypass flow path; A suction temperature detection unit for detecting the temperature of R134a sucked into the turbo compressor,
The flow rate of R134a flowing through the bypass control unit is controlled based on the detection result of the suction temperature detection unit,
The steam generator according to claim 3 or 4, wherein the flow rate of R134a flowing through the low-pressure side decompression unit is controlled based on the flow rate of R134a flowing through the bypass flow path.   The steam generator according to claim 1 or 2, further comprising an intermediate heat exchange section that exchanges heat between R134a that has flowed out of the steam generation section and R134a that has evaporated in the evaporation section. . A bypass flow path for guiding a part of R134a supplied to the intermediate heat exchange section between the high pressure side pressure reduction section and the intermediate section; a bypass control section for controlling the flow rate of R134a flowing through the bypass flow path; A suction temperature detection unit for detecting the temperature of R134a sucked into the turbo compressor,
Based on the detection result of the suction temperature detection unit, the bypass control unit is controlled,
The steam generation apparatus according to claim 6, wherein the high pressure side decompression unit is controlled based on a flow rate of R134a flowing through the bypass flow path. A compression step of compressing the refrigerant R134a into a supercritical state;
A steam generation step for generating superheated steam by heat exchange with R134a in a supercritical state;
A high pressure side pressure reducing step for reducing the pressure of R134a after the heat exchange;
Among R134a decompressed and separated into a gas phase and a liquid phase, an intermediate step of supplying gas phase R134a in the middle of the compression step;
A low pressure side pressure reducing step for further reducing the pressure of the liquid phase R134a of the separated R134a;
An evaporation step of evaporating R134a in the liquid phase further reduced in pressure and supplying the evaporated R134a to the compression step;
A steam generation method characterized in that is provided.

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