Power Generation Unit

Abstract

To provide a power generation device capable of preventing generation of cavitation and reducing an entire size.SOLUTION: A power generation device includes a vaporizer, a turbine, a liquefier, a circulation pump and a jet pump. The vaporizer generates a gas by vaporizing liquid. The turbine is driven by causing the gas generated by the vaporizer to flow in as a working medium. The liquefier generates liquid by cooling and liquefying the gas discharged from the turbine. The circulation pump transmits the liquid generated by the liquefier to the vaporizer. The jet pump is configured to increase a pressure of the liquid generated by the liquefier and then discharge the liquid to the circulation pump.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present invention relate to a power generation device.

Background Art

[0002] FIG. 4 is a diagram schematically showing a main part of a power generation device 1J according to the related art.

[0003] As shown in FIG. 4, the power generation device 1J includes a vaporizer 10, a turbine 30, a liquefier 40, and a circulation pump 50. In the power generation device 1J, a flow path is interposed between each part so as to constitute a cycle in which a medium (including water, a low-boiling point medium, a solution, etc.) circulates and flows through each part.

[0004] Specifically, in the power generation device 1J, the gas F10 generated in the vaporizer 10 flows into the turbine 30 as a working medium, expands in the turbine 30, and performs work. Here, power generation is performed in the generator 31 by driving the turbine 30. Then, in the power generation device 1J, the gas F30 exhausted from the turbine 30 is liquefied into a liquid F40 in the liquefier 40. Thereafter, the liquefied liquid F40 is pressurized by the circulation pump 50. The liquid F50 pressurized by the circulation pump 50 is returned to the vaporizer 10.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0006] The liquid F40 liquefied by the liquefier 40 has a low pressure and is close to the saturated state. Therefore, in the circulation pump 50 for circulating the liquefied liquid F40, since the pressure on the suction side (inlet side) is close to the saturated state, a part of the liquid F40 may vaporize in the circulation pump 50, and cavitation may occur. As a result, there is a possibility of damage to the components (for example, the impeller) constituting the circulation pump 50.

[0007] In order to prevent the occurrence of cavitation, for the circulation pump 50, it is necessary to increase the NPSHa (available NPSH (Net Positive Suction Head)). To achieve this, it is necessary to raise the water level on the suction side of the circulation pump 50 higher than the NPSHr ((required NPSH) (NPSHa > NPSHr)). For this reason, since the overall height of the power generation device 1J becomes high and the whole may become large, there are restrictions on the installation space.

[0008] As described above, in the power generation device, it is not easy to effectively prevent cavitation from occurring in the circulation pump and to miniaturize the overall size. The same problem exists when the power generation device constitutes another cycle such as a Kalina cycle other than when it constitutes a Rankine cycle.

[0009] Therefore, the problem to be solved by the present invention is to provide a power generation device capable of preventing the occurrence of cavitation and realizing miniaturization of the overall size.

Means for Solving the Problem

[0010] The power generation device of the embodiment includes a vaporizer, a turbine, a liquefier, a circulation pump, a jet pump, and Gas-liquid separator andIt includes. The vaporizer generates a gas by vaporizing a liquid. The turbine is driven by the gas generated in the vaporizer flowing in as a working medium. The liquefier generates a liquid by cooling and liquefying the gas exhausted from the turbine. As forms of liquefaction, in addition to the condensation of the gas by a phase change, there is absorption of the gas into the liquid, etc. The circulation pump sends the liquid generated in the liquefier to the vaporizer. The jet pump is configured to boost the pressure of the liquid generated in the liquefier and discharge it to the circulation pump. The gas-liquid separator separates the liquid contained in the gas generated in the vaporizer. The turbine is driven by the gas from which the liquid has been separated in the gas-liquid separator flowing in as the working medium, and the jet pump uses the liquid separated in the gas-liquid separator to boost the pressure of the liquid generated in the liquefier. The liquid whose pressure has been boosted by the jet pump is configured to flow directly into the circulation pump.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0012] <First Embodiment> [A] Configuration, etc. FIG. 1 is a diagram schematically showing the main part of the power generation device 1 according to the first embodiment.

[0013] As shown in FIG. 1, the power generation device 1 of this embodiment includes a vaporizer 10, a turbine 30, a liquefier 40, and a circulation pump 50, similar to the case of the related art (see FIG. 4). In addition to this, the power generation device 1 of this embodiment further includes a jet pump 60. In the power generation device 1, a flow path is interposed between each part so as to form a cycle in which a medium (including water, a low-boiling medium, a mixed medium, a solution, etc.) circulates and flows through each part.

[0014] Each part constituting the power generation device 1 of the present embodiment will be sequentially described.

[0015] The vaporizer 10 is, for example, a cross-flow type evaporator and is configured to generate a gas F10.

[0016] The turbine 30 is configured to be driven by the gas F10 generated in the vaporizer 10 flowing in as a working medium. The gas F10 flowing into the turbine 30 as a working medium expands inside the turbine 30 to perform work, thereby rotating the rotating shaft of the turbine 30. As the rotating shaft of the turbine 30 rotates, the rotating shaft of the generator 31 connected to the rotating shaft of the turbine 30 rotates, and power generation is performed in the generator 31.

[0017] The liquefier 40 is, for example, an indirect contact type condenser and is configured to generate a liquid F40 by cooling and liquefying the gas F30 exhausted from the turbine 30. The liquefier 40 cools the gas F30 using, for example, a cooling medium CF flowing in from the outside, and discharges the cooling medium CF40 used for cooling to the outside. When the power generation device constitutes, for example, a Kalina cycle, the liquefier 40 may be an absorber that absorbs and liquefies the gas exhausted from the turbine 30 into a liquid. Alternatively, the liquefier 40 may be configured to function as both a condenser and an absorber.

[0018] The circulation pump 50 is provided to send the liquid F40 generated in the liquefier 40 to the vaporizer 10. In the present embodiment, the liquid F40 generated in the liquefier 40 flows into the circulation pump 50 via the jet pump 60. That is, the circulation pump 50 boosts the pressure of the liquid F60 flowing in from the jet pump 60, and discharges the pressurized liquid F50 toward the vaporizer 10.

[0019] In this embodiment, the liquid F50 discharged from the circulation pump 50 toward the vaporizer 10 branches and flows to the side of the vaporizer 10 and the side of the jet pump 60 at the branch portion J50. The liquid F50a that branches and flows to the side of the vaporizer 10 is vaporized in the vaporizer 10 by being heated as described above, and flows out of the vaporizer 10 as the gas F10. On the other hand, the liquid F50b that branches and flows to the side of the jet pump 60 flows into the jet pump 60 as a driving fluid via the flow rate adjustment valve V60.

[0020] The jet pump 60 is driven using the liquid F50b that has flowed in as a driving fluid, boosts the pressure of the liquid F40 generated in the liquefier 40, and discharges it to the circulation pump 50.

[0021] Specifically, the jet pump 60 sucks in the liquid F40 generated in the liquefier 40 by the liquid F50b that has flowed in as a driving fluid. In the jet pump 60, the liquid F40 sucked in as a suction fluid from the liquefier 40 and the liquid F50b that has flowed in as a driving fluid are mixed, and momentum exchange occurs between the two. As a result, the pressure of the liquid F40 sucked in from the liquefier 40 increases by the diffuser (not shown) according to the momentum of the liquid F50b that has flowed in as a driving fluid. Then, the mixed medium of the liquid F40 and the liquid F50b is discharged from the jet pump 60 to the circulation pump 50 as the pressurized liquid F60.

[0022] [B]Summary As described above, in the power generation device 1 of the present embodiment, the jet pump 60 boosts the pressure of the liquid F40 generated in the liquefier 40 and discharges it to the circulation pump 50. Therefore, at the inlet of the circulation pump 50, a liquid F60 with a higher pressure flows in than in the case where the jet pump 60 is not installed (see FIG. 4). As a result, in the present embodiment, it is possible to ensure that NPSHa of the circulation pump 50 is in a state where it is greater than NPSHr (NPSHa > NPSHr), and the occurrence of cavitation can be easily suppressed. Along with this, in the present embodiment, since it is not necessary to raise the suction-side water level of the circulation pump 50 higher than in the case where the jet pump 60 is not installed (see FIG. 4), the overall height of the power generation device 1 is reduced, and the whole can be miniaturized.

[0023] In the above embodiment, the case where the vaporizer 10 is a through-flow type evaporator has been described, but the present invention is not limited to this.

[0024] Also, in the above embodiment, it may be configured to control the opening degree of the flow rate adjustment valve V60. For example, the pressure of the medium flowing from the jet pump 60 to the circulation pump 50 may be detected by a pressure sensor (not shown), and a control device (not shown) may control the opening degree of the flow rate adjustment valve V60 according to the detected pressure data. Specifically, when the detected pressure data is higher than a predetermined set range, the opening degree of the flow rate adjustment valve V60 is narrowed. On the other hand, when the detected pressure data is lower than a predetermined set range, the opening degree of the flow rate adjustment valve V60 is widened. Thereby, it is possible to control the pressure of the medium flowing from the jet pump 60 to the circulation pump 50 to be within the set range.

[0025] <Second Embodiment> [A] Configuration, etc. FIG. 2 is a diagram schematically showing a main part of a power generation device 1b according to the second embodiment.

[0026] As shown in FIG. 2, unlike the case of the first embodiment (see FIG. 1), the power generation device 1b of this embodiment further includes a gas-liquid separator 110, an intermediate heat exchanger 120, and a cooling heat exchanger 130 (first cooling heat exchanger). Except for these points and related points, this embodiment is the same as the case of the first embodiment. Therefore, regarding overlapping matters, the description will be omitted as appropriate. In the power generation device 1b of this embodiment, the gas-liquid separator 110 is installed to separate the liquid F110b mixed and contained in the gas F10 generated in the vaporizer 10.

[0027] The gas F110a from which the liquid F110b has been separated in the gas-liquid separator 110 flows into the turbine 30 as a working medium. On the other hand, the liquid F110b separated from the gas F110a in the gas-liquid separator 110 flows into the jet pump 60 as a driving fluid via the intermediate heat exchanger 120 and the cooling heat exchanger 130.

[0028] The intermediate heat exchanger 120 is installed to cool the liquid F110b flowing from the gas-liquid separator 110 via the cooling heat exchanger 130 to the jet pump 60 using the liquid F50 flowing from the circulation pump 50 to the vaporizer 10.

[0029] In the intermediate heat exchanger 120, heat exchange is performed between the liquid F50 flowing in from the circulation pump 50 and the liquid F110b flowing in from the gas-liquid separator 110. The intermediate heat exchanger 120 is, for example, a counter-flow type heat exchanger, and the flow direction of the liquid F50 flowing in from the circulation pump 50 and the flow direction of the liquid F110b flowing in from the gas-liquid separator 110 are opposite.

[0030] In the intermediate heat exchanger 120, the temperature of the liquid F50 flowing in from the circulation pump 50 is lower than the temperature of the liquid F110b flowing in from the gas-liquid separator 110. Therefore, the liquid F110b flowing in from the gas-liquid separator 110 is cooled by the heat exchange in the intermediate heat exchanger 120, and the liquid F120a cooled in the intermediate heat exchanger 120 flows out to the cooling heat exchanger 130.

[0031] In contrast, the liquid F50 flowing in from the circulation pump 50 is heated by heat exchange in the intermediate heat exchanger 120, and the liquid F120b heated in the intermediate heat exchanger 120 flows out to the vaporizer 10.

[0032] The cooling heat exchanger 130 is installed to further cool the liquid F120a cooled in the intermediate heat exchanger 120.

[0033] In the cooling heat exchanger 130, heat exchange is performed between the liquid F120a cooled in the intermediate heat exchanger 120 and the cooling medium CF flowing in from the outside.

[0034] In the cooling heat exchanger 130, the temperature of the liquid F120a cooled in the intermediate heat exchanger 120 is higher than the temperature of the cooling medium CF flowing in from the outside. For this reason, the cooling medium CF flowing in from the outside is heated by heat exchange in the cooling heat exchanger 130. And the cooling medium CF130 heated in the cooling heat exchanger 130 flows out to the liquefier 40. In the liquefier 40, the gas F30 is cooled using the cooling medium CF130 flowing in from the cooling heat exchanger 130, and the cooling medium CF40 used for cooling is discharged to the outside.

[0035] In contrast, the liquid F120a cooled in the intermediate heat exchanger 120 is further cooled by heat exchange in the cooling heat exchanger 130. And the liquid F130 further cooled in the cooling heat exchanger 130 flows out to the jet pump 60 via the flow rate adjustment valve V60. The jet pump 60 uses the liquid F130 further cooled in the cooling heat exchanger 130 as a driving fluid, sucks in the liquid F40 generated in the liquefier 40 as a suction fluid, and boosts the pressure.

[0036] [B]Summary As described above, in the power generation device 1b of the present embodiment, the jet pump 60 uses the liquid F110b separated by the gas-liquid separator 110 and supplied via the intermediate heat exchanger 120 and the cooling heat exchanger 130 as the driving fluid to boost the pressure of the liquid F40 generated in the liquefier 40. Then, the liquid F60 pressurized by the jet pump 60 flows into the circulation pump 50. Therefore, also in the present embodiment, as in the case of the first embodiment, at the inlet of the circulation pump 50, a liquid F60 with a higher pressure flows in than in the case where the jet pump 60 is not installed (see FIG. 4). As a result, it is possible to ensure that NPSHa is greater than NPSHr for the circulation pump 50 (NPSHa > NPSHr), and the occurrence of cavitation can be easily suppressed. Along with this, also in the present embodiment, since it is not necessary to raise the suction-side water level of the circulation pump 50 higher than in the case where the jet pump 60 is not installed (see FIG. 4), the overall height of the power generation device 1 becomes lower, and the whole can be miniaturized.

[0037] In the present embodiment, different from the case of the first embodiment, a part of the liquid F50b of the liquid F50 discharged from the circulation pump 50 to the vaporizer 10 is not supplied as the driving fluid to the jet pump 60. Therefore, in the present embodiment, it is not necessary to increase the flow rate corresponding to the liquid F50b supplied from the circulation pump 50 to the jet pump 60 with respect to the flow rate of the liquid F50 discharged from the circulation pump 50.

[0038] <Third Embodiment> [A] Configuration, etc. FIG. 3 is a diagram schematically showing the main part of the power generation device 1c according to the third embodiment.

[0039] As shown in FIG. 3, different from the case of the first embodiment (see FIG. 1), the power generation device 1c of the present embodiment further includes a sub-circulation pump 210 and a cooling heat exchanger 220 (second cooling heat exchanger). Except for these points and related points, the present embodiment is the same as the case of the first embodiment. Therefore, regarding overlapping matters, the description will be omitted as appropriate.

[0040] The auxiliary circulation pump 210 is configured to boost the pressure of a part of the liquid F60b among the liquid F60 boosted in pressure by the jet pump 60.

[0041] The cooling heat exchanger 220 is configured to cool the liquid F210 boosted in pressure by the auxiliary circulation pump 210.

[0042] Specifically, in the cooling heat exchanger 220, heat exchange is performed between the liquid F210 flowing in from the auxiliary circulation pump 210 and the cooling medium CF flowing in from the outside.

[0043] In the cooling heat exchanger 220, the temperature of the liquid F210 flowing in from the auxiliary circulation pump 210 is higher than the temperature of the cooling medium CF flowing in from the outside. For this reason, the cooling medium CF flowing in from the outside is heated by the heat exchange in the cooling heat exchanger 220, and the cooling medium CF220 heated in the cooling heat exchanger 220 flows out to the outside.

[0044] On the other hand, the liquid F210 flowing in from the auxiliary circulation pump 210 is cooled by the heat exchange in the cooling heat exchanger 220. Then, the liquid F220 cooled in the cooling heat exchanger 220 branches and flows to the side of the liquefier 40 and the side of the jet pump 60 at the branch portion J220.

[0045] The liquid F220a that branches and flows to the side of the liquefier 40 is used to cool and liquefy the gas F30 exhausted from the turbine 30 in the liquefier 40. In the present embodiment, the liquefier 40 is, for example, of a direct contact type, and is configured to execute the liquefaction of the gas F30 exhausted from the turbine 30 by spraying the liquid F220a that branches and flows to the side of the liquefier 40. Then, the liquid F40 liquefied in the liquefier 40 is supplied to the jet pump 60.

[0046] On the other hand, the liquid F220b that branches off and flows toward the jet pump 60 flows into the jet pump 60 as a driving fluid via the flow rate adjustment valve V60. The jet pump 60 uses the liquid F220b cooled in the cooling heat exchanger 220 as a driving fluid, sucks in the liquid F40 generated in the liquefier 40 as a suction fluid, and boosts the pressure.

[0047] After that, the liquid F60 discharged by the jet pump 60 after boosting the pressure branches off and flows toward the side of the circulation pump 50 and the side of the auxiliary circulation pump 210 at the branch portion J60. The liquid F60b that branches off and flows toward the side of the auxiliary circulation pump 210 is supplied to the liquefier 40 via the auxiliary circulation pump 210 as described above. On the other hand, the liquid F60a that branches off and flows toward the side of the vaporizer 10 is pressurized by the circulation pump 50, flows into the vaporizer 10, is vaporized by being heated in the vaporizer 10, and flows out of the vaporizer 10 as the gas F10.

[0048] [B]Summary As described above, in the power generation device 1c of the present embodiment, the liquefier 40 cools and liquefies the gas F30 exhausted from the turbine 30 using a part of the liquid F220a of the liquid F220 cooled in the cooling heat exchanger 220. Then, the jet pump 60 sucks in and boosts the pressure of the liquid F40 generated in the liquefier 40 using the remaining liquid F220b of the liquid F220b cooled in the cooling heat exchanger 220 as a driving fluid. Then, the liquid F60 (F60a) boosted by the jet pump 60 flows into the circulation pump 50. Therefore, also in the present embodiment, as in the case of the first embodiment, at the inlet of the circulation pump 50, a liquid F60 (F60a) with a higher pressure flows in than when the jet pump 60 is not installed (see FIG. 4). As a result, it is possible to ensure that NPSHa is greater than NPSHr for the circulation pump 50, and the occurrence of cavitation can be easily suppressed. Along with this, also in the present embodiment, since it is not necessary to raise the suction side water level of the circulation pump 50 more than when the jet pump 60 is not installed (see FIG. 4), the overall height of the power generation device 1 becomes lower, and the whole can be miniaturized.

[0049] <Others> Although some embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. These embodiments and their modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Description of Reference Numerals

[0050] 1: Power generation device, 1J: Power generation device, 1b: Power generation device, 1c: Power generation device, 10: Vaporizer, 30: Turbine, 31: Generator, 40: Liquefier, 50: Circulation pump, 60: Jet pump, 110: Gas-liquid separator, 120: Intermediate heat exchanger, 130: Cooling heat exchanger, 210: Sub-circulation pump, 220: Cooling heat exchanger, CF: Cooling medium, CF130: Cooling medium, CF220: Cooling medium, CF40: Cooling medium, F10: Gas, F110a: Gas, F110b: Liquid, F120a: Liquid, F120b: Liquid, F130: Liquid, F210: Liquid, F220: Liquid, F220a: Liquid, F220b: Liquid, F30: Gas, F40: Liquid, F50: Liquid, F50a: Liquid, F50b: Liquid, F60: Liquid, F60a: Liquid, F60b: Liquid, J220: Branch portion, J50: Branch portion, J60: Branch portion, V60: Flow rate adjustment valve

Claims

1. a vaporizer for generating a gas by vaporizing a liquid; A turbine driven by the gas generated in the carburetor flowing in as a working medium; a liquefier for cooling and liquefying the gas exhausted from the turbine to produce a liquid; a circulation pump for sending the liquid produced in the liquefier to the vaporizer; A power generating device comprising: a jet pump configured to pressurize the liquid produced in the liquefier and discharge the liquid to the circulation pump; a gas-liquid separator for separating liquid contained in the gas produced by the vaporizer; having The turbine is driven by the gas from which the liquid has been separated in the gas-liquid separator flowing in as a working medium, The jet pump uses the liquid separated in the gas-liquid separator to pressurize the liquid produced in the liquefier, The liquid pressurized by the jet pump is configured to directly flow into the circulation pump. Power generating device.

2. an intermediate heat exchanger that cools liquid flowing from the gas-liquid separator to the jet pump by using liquid flowing from the circulation pump to the vaporizer; a first cooling heat exchanger for further cooling the liquid cooled in the intermediate heat exchanger; having The jet pump is configured to pressurize the liquid produced in the liquefier by using the liquid cooled in the first cooling heat exchanger.

2. The power generating device according to claim 1.

3. A vaporizer that generates a gas by vaporizing a liquid; A turbine driven by the gas generated in the carburetor flowing in as a working medium; a liquefier for cooling and liquefying the gas exhausted from the turbine to produce a liquid; a circulation pump for sending the liquid produced in the liquefier to the vaporizer; A power generating device comprising: a jet pump configured to pressurize the liquid produced in the liquefier and discharge the liquid to the circulation pump; a sub-circulation pump for further pressurizing a portion of the liquid pressurized by the jet pump; having The liquefier cools and liquefies the gas exhausted from the turbine using a portion of the liquid driven by the secondary circulation pump, The jet pump is configured to pressurize the liquid produced in the liquefier by using the remainder of the liquid driven by the secondary circulation pump. Power generating device.

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