JP6564710B2 - Compressor system - Google Patents

Description

  The present disclosure relates to a compressor system and a waste heat recovery power generation method.

  Since the compressor generates heat in the compression process, the compressed gas is heated to a high temperature state. The compressed gas can be passed through a cooler and cooled. The heat removed from the compressed gas is transferred to the cooling water by heat exchange in the cooler. This cooling water is cooled through a cooling tower or the like. Thus, the heat removed from the compressed gas can eventually be released into the atmosphere as energy.

  As described in Patent Document 1, as a background art, there is known a device that passes cooling water through a cooler for cooling compressed gas, takes out water vapor in the cooler, and drives the steam turbine to recover energy as electric power. Yes.

JP 2005-315244 A

  In the conventional apparatus described above, the compressor efficiency can be improved. However, some of the energy output from the compressor is still discarded. That is, there is room for improvement in energy recovery from the compressor.

  The present disclosure describes a compressor system and a waste heat recovery power generation method that can increase the efficiency of energy recovery from the compressor.

  A compressor system according to an aspect of the present disclosure includes a compressor that generates compressed gas, a cooler that transfers heat from the compressed gas to water by heat exchange between the compressed gas generated by the compressor and water, and a cooler A binary power generation device including an evaporator that heats the working medium by exchanging heat between the water heated by the working medium and the working medium, and a generator that generates power using the working medium that is heated and evaporated by the evaporator. The evaporator includes a water outlet through which water flowing out of the cooler passes, and the binary power generator evaporator includes a water inlet through which water flows into the evaporator, and the water outlet of the cooler and the water inlet of the evaporator are Connected through a hot water line.

  According to the compressor system concerning one mode of this indication, the efficiency of energy recovery from a compressor can be raised.

It is a figure showing a schematic structure of a compressor system concerning a 1st embodiment of this indication. It is a flowchart which shows the execution procedure of the water temperature control in the compressor system of FIG. It is a figure which shows the 1st modification of 1st Embodiment. It is a figure which shows the 2nd modification of 1st Embodiment. It is a figure which shows schematic structure of the compressor system which concerns on 2nd Embodiment of this indication. It is a figure which shows the 1st modification of 2nd Embodiment. It is a figure which shows the 2nd modification of 2nd Embodiment. It is a figure which shows schematic structure of the compressor system which concerns on 3rd Embodiment of this indication. It is a flowchart which shows the execution procedure of the water temperature control in the compressor system of FIG. It is a figure which shows the modification of 3rd Embodiment.

A compressor system according to an aspect of the present disclosure includes a compressor that generates compressed gas, a cooler that transfers heat from the compressed gas to water by heat exchange between the compressed gas generated by the compressor and water, and a cooler in an evaporator for heating the working medium by heat exchange with the heated water and the working medium, a binary power plant comprising a generator for generating electric power by heated by vaporized working medium in the evaporator, it flows out from the evaporator A cooling source capable of cooling water to be cooled, and the cooler includes a water outlet through which water flowing out of the cooler passes and a water inlet through which water flowing into the cooler passes , a water inlet through which water flowing into the evaporator, and a water outlet the water passes flowing from the evaporator, and the water outlet of the cooler the evaporator water inlet is connected via a hot water line The cooling source and the water inlet of the cooler are connected via a water line The water outlet of the evaporator and the cooling source are connected via a first return line, and the hot water line or water line is provided with a hot water pump for passing water through the evaporator. The line is provided with a first valve for adjusting the heat utilization based on the flow of water from the water outlet of the cooler into the evaporator, and the cooling source is connected to the cooler via the water line. Including a hot water tank connected to the water inlet, the cooler being connected to the hot water tank via a bypass line and a first return line branching between the water outlet of the cooler and the first valve; The bypass line is provided with a second valve for adjusting a bypass amount based on returning water from the water outlet of the cooler to the hot water tank .

According to this compressor system, the heat of the compressed gas is transferred to water in the cooler. The water heated by the cooler flows through the water outlet of the cooler, the hot water line, and the water inlet of the evaporator into the binary power generator evaporator. In the evaporator, the working medium is heated and evaporated. As a result, the generator generates power. The binary power generation apparatus uses the thermal energy of hot water of less than 100 ° C. to evaporate the working medium having a low boiling point, and generates power with the generator. By combining a binary power generation device that enables effective use of low heat with a compressor, the thermal energy of the compressed gas that was conventionally discarded is recovered and used for power generation. Therefore, the efficiency of energy recovery from the compressor can be increased. The water used for heating the working medium in the evaporator is sent to the cooling source via the first return line and cooled in the cooling source. And the comparatively low temperature water produced with the cooling source can be sent to a cooler via a water line, and can be used as cooling water. The heat utilization amount and the bypass amount can be adjusted by opening and closing the first valve and the second valve. Thereby, the temperature of the water flowing into the cooler can be adjusted as desired. As a result, the amount of heat exchange in the cooler can be set appropriately. The relatively low temperature water stored in the hot water tank can be used as cooling water for the cooler. Moreover, the heat utilization amount based on sending the warm water from a cooler to an evaporator, and the bypass amount based on sending the said warm water to a hot water storage tank can be adjusted easily. According to the compressor system provided with the hot water storage tank, the amount of heat can be easily managed.

  In some embodiments, the binary power generation device includes a medium circulation line for circulating the working medium and a condenser that cools the working medium by heat exchange between the working medium and water, the medium circulation line being an evaporator. Through the generator and condenser, the cooling source includes a cooling device connected to the condenser to cool the water. According to the cooling device, it is easy to cool the working medium in the binary power generation device. The cooling device contributes to stable operation of the binary power generation device.

  In some embodiments, further comprising a controller that obtains a temperature of water through the hot water line or the water line, the controller based on the temperature of the water through the hot water line or the water line, or the first valve, the second valve, or Control the hot water pump. In this case, the controller adjusts the amount of water supplied to the cooler and the evaporator by controlling the first valve, the second valve, or the hot water pump. The heat exchange state in the cooler can be controlled by adjusting the amount of water supplied based on the temperature of water passing through the hot water line or the water line. According to this, flexible control becomes possible.

  In some aspects, the compressor system further comprises a controller that obtains the temperature of the hot water line or the water passing through the water line, the hot water tank and the cooling device being a supply for supplying water from the cooling device to the hot water tank. Connected via a line and connected via a second return line for returning water from the hot water tank to the cooling device, the supply line adjusts the amount of water supplied from the cooling device to the hot water tank A possible temperature regulating valve is provided and the controller controls the temperature regulating valve based on the temperature of the hot water line or the water passing through the water line. In this case, the controller adjusts the amount of water supplied to the hot water tank by controlling the temperature adjustment valve. By adjusting the supply amount of water based on the temperature of the hot water line or the water passing through the water line, the water temperature in the hot water tank can be maintained at a water temperature suitable for heat exchange in the cooler. Moreover, when the amount of stored water in the hot water tank is excessive, water can be returned to the cooling device via the second return line.

  Embodiments of the present invention will be specifically described below with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted.

  First, a compressor system 1 according to the first embodiment will be described with reference to FIG. As shown in FIG. 1, the compressor system 1 is a system in which a binary power generation device 3 is combined with a compressor unit 2. The compressor system 1 has a configuration capable of recovering heat generated by the compressor 6 of the compressor unit 2 with high efficiency.

  Hereinafter, in each figure showing the configuration of the compressor system, the electrical wiring is shown by a thick solid line, the gas system line is shown by a broken line, the water system line is shown by a solid line, and the working medium system line is two. It is shown with a dotted line. In the present specification, the “line” means a pipe or conduit through which a fluid flows, or a space. Also, “via” means that a line is interposed between the two devices. When a fluid flows between two devices via a line, it means that the fluid flows via that line.

  The compressor system 1 includes a compressor unit 2 that generates compressed air, a binary power generation device 3 that generates power using waste heat of the compressor unit 2, and heat used in the compressor unit 2 and the binary power generation device 3. And a cooling device (cooling source) 4 for cooling water as a medium. The water used in the compressor system 1 is not particularly limited. Tap water may be used, and industrial water may be used. In the compressor system 1, water serves both as cooling water that cools the working medium of the binary power generation device 3, and waste heat recovery of the compressor unit 2 and a heat medium as a heat source of the binary power generation device 3.

  The compressor system 1 includes a connection unit 5 that connects the compressor unit 2, the binary power generation device 3, and the cooling device 4. The connection unit 5 includes a plurality of lines that connect the devices, and a pump or a valve provided in the lines. The line may be provided with a temperature sensor that measures the temperature of air or water, a flow sensor that measures the flow rate of air or water, and the like.

  The compressor unit 2 includes one or more compressors 6 and one or more coolers for cooling the compressed air generated in the compressors 6. In the compressor system 1, the compressor unit 2 includes one compressor 6 and three coolers.

  The compressor 6 is a turbo compressor, for example. The compressor 6 includes one electric motor 7, a gear 8 connected to the electric motor 7, and three compression units driven by the gear 8. The compressor 6 includes a first stage compression unit 9a, a second stage compression unit 9b, and a third stage compression unit 9c. A gas suction line L1 is connected to the gas inlet of the first stage compression unit 9a. Both ends of the first compressed gas line L2 are connected to the first stage compression unit 9a and the second stage compression unit 9b, respectively. Both ends of the second compressed gas line L3 are connected to the second-stage compression unit 9b and the third-stage compression unit 9c, respectively. A third compressed gas line L4 is connected to the gas outlet of the third stage compression unit 9c.

  The type of the compressor 6 is not particularly limited. The compressor 6 may be a screw compressor or a reciprocating compressor. Any compressor may be applied as long as it generates heat in the compression step.

  The cooler of the compressor unit 2 transfers heat from the compressed air to the water by heat exchange between the compressed air generated by the compressor 6 and the water. The compressor unit 2 includes a first cooler 11, a second cooler 12, and a third cooler 13 corresponding to the three-stage compression unit of the compressor 6.

  A first compressed gas line L2 is connected to the first cooler 11. The first compressed gas line L2 includes a first heat exchange part L2a in the first cooler 11. In the 1st cooler 11, the 1st heat exchange part L11a is provided. A second compressed gas line L3 is connected to the second cooler 12. The second compressed gas line L3 includes a second heat exchange part L3a in the second cooler 12. In the second cooler 12, a second heat exchange part L12a is provided. A third compressed gas line L4 is connected to the third cooler 13. The third compressed gas line L4 includes a third heat exchange part L4a in the third cooler 13. In the third cooler 13, a third heat exchanging part L13a is provided. The compressed air is cooled by the first cooler 11, the second cooler 12, and the third cooler 13, and at the same time, the water is heated (heated).

  The compressor unit 2 may include a housing that accommodates each device and line described above. The first cooler 11 (compressor unit 2) includes a first water inlet 2a through which water flowing into the first cooler 11 passes, and a first water outlet 2b through which water flowing out from the first cooler 11 passes. . The second cooler 12 (compressor unit 2) includes a second water inlet 2c through which water flowing into the second cooler 12 passes and a second water outlet 2d through which water flowing out of the second cooler 12 passes. . The third cooler 13 (compressor unit 2) includes a third water inlet 2e through which water flowing into the third cooler 13 passes and a third water outlet 2f through which water flowing out from the third cooler 13 passes. .

  The air sucked into the compressor 6 through the gas suction line L1 is compressed by the compressor 6, cooled by the first cooler 11, the second cooler 12, and the third cooler 13, and from the compressor unit 2. Discharged. The temperature of the compressed air is, for example, 100 ° C. or more at the respective outlets of the first stage compression unit 9a, the second stage compression unit 9b, and the third stage compression unit 9c. The temperature of the compressed air is, for example, less than 50 ° C. at each air outlet of the first cooler 11, the second cooler 12, and the third cooler 13. On the other hand, the first cooler 11, the second cooler 12, and the third cooler 13 heat water to such an extent that the water does not boil at atmospheric pressure (so that the water temperature is less than 100 ° C.). ing.

  Next, the binary power generator 3 will be described. The binary power generator 3 is configured to be able to generate power using hot water heated by the first cooler 11 and the second cooler 12 as a heat source. The binary power generator 3 is a small power generator capable of generating power with an output of about 5 to 20 kW, for example. The binary power generation device 3 is a device that employs, for example, an organic rankine cycle (ORC). In the binary power generation device 3, heat exchange is performed between the hot water heated by the first cooler 11 and the second cooler 12 and the working medium in the binary power generation device 3. The working medium used for the binary power generator 3 is, for example, an inert gas.

  The binary power generator 3 includes one evaporator 21, one turbine generator 20, one condenser 22, and a medium circulation line L <b> 20 passing through the evaporator 21, the turbine generator 20, and the condenser 22. The evaporator 21 heats the working medium by heat exchange between the hot water heated by the first cooler 11 and the second cooler 12 and the working medium. The turbine generator 20 includes a turbine 20a, for example. The turbine generator 20 generates electricity by rotating the turbine 20a with the working medium heated and evaporated by the evaporator 21. The condenser 22 cools and condenses the working medium by heat exchange between the working medium and the cooling water, and liquefies. A power converter 23 is connected to the turbine generator 20. The power converter 23 includes devices such as an AC-DC converter, a grid interconnection converter, and an insulation transformer, for example.

  The medium circulation line L20 includes a first medium line L21 and a second medium line L22. The first medium line L21 and the second medium line L22 constitute a loop-shaped medium circulation line L20. The first medium line L21 includes an evaporation heat exchange part L21a provided in the evaporator 21. The second medium line L22 includes a heat exchanger L22a for condensation provided in the condenser 22. The first medium line L21 connects the condenser 22 and the evaporator 21 on the low temperature side. The first medium line L21 is provided with a circulation pump 24 for circulating the working medium. The second medium line L22 connects the evaporator 21 and the condenser 22 on the high temperature side. In the middle of the second medium line L22, the turbine 20a of the turbine generator 20 is connected.

  A shutoff valve 25 is provided in the second medium line L22 between the evaporator 21 and the turbine 20a. A medium bypass line L23 that bypasses the turbine generator 20 and the shutoff valve 25 is connected to the second medium line L22. A bypass valve 26 is provided in the medium bypass line L23. The binary power generation device 3 includes a controller 30 that comprehensively controls power generation in the binary power generation device 3. The controller 30 is a computer composed of hardware such as a CPU (Central Processing Unit), ROM (Read Only Memory), and RAM (Random Access Memory), and software such as a program stored in the ROM. .

  The controller 30 is electrically connected to the power converter 23. The controller 30 inputs information related to the generated power from the power converter 23. The controller 30 is electrically connected to the circulation pump 24, the shutoff valve 25, and the bypass valve 26. The controller 30 can control the circulation pump 24, the shutoff valve 25, and the bypass valve 26 based on information input from the power converter 23. During normal power generation, the controller 30 activates the circulation pump 24, opens the shut-off valve 25, and closes the bypass valve 26. When preventing the turbine 20a from over-rotating, the controller 30 stops the circulation pump 24, closes the shut-off valve 25, and opens the bypass valve 26. When stopping the power generation in the binary power generation device 3, the controller 30 stops the circulation pump 24, fully closes the shutoff valve 25, and fully opens the bypass valve 26.

  The binary power generation device 3 may include a housing that accommodates each device and line described above. The evaporator 21 (binary power generator 3) includes a first water inlet 3a through which hot water flowing into the evaporator 21 passes and a first water outlet 3b through which hot water flowing out of the evaporator 21 passes. The condenser 22 (binary power generation device 3) includes a second water inlet 3c through which cooling water flowing into the condenser 22 passes, and a second water outlet 3d through which water flowing out of the condenser 22 passes.

  Next, the cooling device 4 that is a cooling source will be described. The cooling device 4 is, for example, a cooling tower. A cooling air line L40 is connected to the cooling device 4. The cooling device 4 is connected to the condenser 22 of the binary power generation device 3 through a circulation channel. A cooling water line LW passes through the cooling device 4. The cooling device 4 includes a water inlet 4a through which water flowing into the cooling device 4 passes and a water outlet 4b through which water flowing out of the cooling device 4 passes. The cooling device 4 cools water by heat exchange between the heat exchange unit LWa in the cooling device 4 and the heat exchange unit L40a of the cooling air line L40.

  More specifically, the cooling device 4 cools water for liquefying the working medium. In the compressor system 1, the cooling device 4 also cools water (hot water) flowing out from the evaporator 21 of the binary power generation device 3. The cooling device 4 also cools water (hot water) that flows out of the first cooler 11 and the second cooler 12 of the compressor unit 2 and bypasses without passing through the evaporator 21 of the binary power generation device 3. The cooling device 4 also cools water (hot water) flowing out from the third cooler 13 of the compressor unit 2. The cooling device 4 functions as a cooling source for all water used in the compressor system 1. The type of the cooling device 4 is not particularly limited.

  The compressor unit 2, the binary power generation device 3, and the cooling device 4 described above are connected to each other by a connection unit 5. Hereinafter, the connection unit 5 will be described in detail.

  A cooling water pump 36 is provided in the cooling water line LW connected to the cooling device 4. The cooling water line LW branches to the supply line L10 and the cooling water line L19 on the downstream side of the cooling water pump 36. The water outlet 4b of the cooling device 4 and the second water inlet 3c of the condenser 22 are connected via a cooling water line L19. The second water outlet 3d of the condenser 22 and the water inlet 4a of the cooling device 4 are connected via a cooling water line L19. The cooling water line L19 includes a heat exchanger L19a for condensation provided in the condenser 22. Heat exchange is performed between the heat exchanger L19a for condensation and the heat exchanger L22a for condensation.

  The supply line L <b> 10 connects the cooling device 4 and the compressor unit 2. A first water temperature sensor 37 is provided in the supply line L10. The supply line L10 branches to the first cooling line L11, the second cooling line L12, and the third cooling line L13 on the downstream side of the first water temperature sensor 37.

  The water outlet 4b of the cooling device 4 and the first water inlet 2a of the first cooler 11 are connected via a supply line L10 and a first cooling line L11. The first cooling line L11 includes a first heat exchange part L11a provided in the first cooler 11. Heat exchange is performed between the first heat exchange unit L11a and the first heat exchange unit L2a. The water outlet 4b of the cooling device 4 and the second water inlet 2c of the second cooler 12 are connected via a supply line L10 and a second cooling line L12. The second cooling line L12 includes a second heat exchange part L12a provided in the second cooler 12. Heat exchange is performed between the second heat exchange unit L12a and the second heat exchange unit L3a. The water outlet 4b of the cooling device 4 and the third water inlet 2e of the third cooler 13 are connected via a supply line L10 and a third cooling line L13. The third cooling line L13 includes a third heat exchange part L13a provided in the third cooler 13. Heat exchange is performed between the third heat exchange unit L13a and the third heat exchange unit L4a.

  The connection unit 5 is configured such that waste heat can be supplied from the first cooler 11 and the second cooler 12 to the binary power generation device 3. The first water outlet 2b of the first cooler 11 and the second water outlet 2d of the second cooler 12 are connected to the first water inlet 3a of the evaporator 21 via a hot water line L15. That is, the first cooling line L11 and the second cooling line L12 merge at the downstream side of the first cooler 11 and the second cooler 12, and are connected to one hot water line L15. A hot water pump 31 for passing hot water through the condenser 22 is provided in the hot water line L15. The hot water line L15 includes an evaporation heat exchange section L15a provided in the evaporator 21. Heat exchange is performed between the evaporation heat exchange section L15a and the evaporation heat exchange section L21a. With these configurations, in the compressor system 1, the waste heat generated in the compressor unit 2 can be used by the binary power generation device 3.

  The warm water line L15 is provided with a first valve 32 on the upstream side of the warm water pump 31. The opening degree of the first valve 32 can be adjusted by the control of the controller 60 described later. A second water temperature sensor 38 and a first flow rate sensor 39 are provided in the first cooling line L11 and the second cooling line L12 that merge on the downstream side of the first cooler 11 and the second cooler 12. The second water temperature sensor 38 and the first flow rate sensor 39 may be provided in the hot water line L15.

  The first water outlet 3b of the evaporator 21 of the binary power generation device 3 and the water inlet 4a of the cooling device 4 are connected via a first return line L16. The first return line L16 merges with the cooling water line L19 from the second water outlet 3d of the condenser 22. The third water outlet 2f of the third cooler 13 and the water inlet 4a of the cooling device 4 are connected.

  On the other hand, the first water outlet 2b of the first cooler 11 and the second water outlet 2d of the second cooler 12 are connected to the water inlet 4a of the cooling device 4 via the first return line L16. More specifically, the first cooling line L11 and the second cooling line L12 that merge on the downstream side of the first cooler 11 and the second cooler 12 are connected via a bypass line L14 that branches at a position different from the hot water line L15. And connected to the first return line L16. The first water outlet 2b of the first cooler 11 and the second water outlet 2d of the second cooler 12 are connected to the water inlet 4a of the cooling device 4 via the bypass line L14 and the first return line L16. ing. A second valve 33 is provided in the bypass line L14. The opening degree of the second valve 33 can be adjusted by the control of the controller 60 described later.

  The first valve 32 on the hot water line L15 uses heat based on flowing warm water from the first water outlet 2b of the first cooler 11 and the second water outlet 2d of the second cooler 12 into the evaporator 21. It is provided to adjust the amount. The second valve 33 on the bypass line L14 is based on the amount of bypass based on returning the hot water from the first water outlet 2b of the first cooler 11 and the second water outlet 2d of the second cooler 12 directly to the cooling device 4. Is provided to adjust.

  The compressor system 1 further includes a controller 60 for controlling the amount of heat transferred between the compressor unit 2, the binary power generation device 3, and the cooling device 4. The controller 60 is a computer composed of hardware such as a CPU, ROM, and RAM, and software such as a program stored in the ROM.

  The controller 60 is capable of information communication with the first water temperature sensor 37, and sequentially acquires the temperature of water passing through the supply line L10. In other words, the controller 60 acquires the temperature Tb of the cooling water flowing into the first cooler 11, the second cooler 12, and the third cooler 13. The controller 60 can communicate with the second water temperature sensor 38 and sequentially acquires the temperature of water passing through the hot water line L15. In other words, the controller 60 acquires the temperature Ta of the hot water flowing out from the first cooler 11 and the second cooler 12, that is, the temperature Ta of the hot water flowing into the evaporator 21. The controller 60 can communicate information with the first flow rate sensor 39, and acquires the flow rate of water passing through the hot water line L15. In other words, the controller 60 acquires the total flow rate F of hot water flowing out from the first cooler 11 and the second cooler 12, that is, the flow rate F of hot water flowing into the evaporator 21. The controller 60 can transmit control signals to the hot water pump 31, the first valve 32, and the second valve 33. The controller 60 performs a predetermined calculation using information acquired from each sensor, and controls the hot water pump 31, the first valve 32, and the second valve 33 based on the calculation result. The controller 60 can communicate information with the controller 30 of the binary power generator 3.

  The controller 60 may perform control based on information output from any one or two of the first water temperature sensor 37, the second water temperature sensor 38, and the first flow rate sensor 39. The controller 60 may control any one or two of the hot water pump 31, the first valve 32, and the second valve 33. The hot water pump 31 or the first valve 32 may be replaced with a manual valve or an orifice.

  Next, a waste heat recovery power generation method in the compressor system 1 will be described with reference to FIG. More specifically, the water temperature control (thermal control) performed by the controller 60 will be described. First, compressed air is generated using the compressor 6 of the compressor unit 2. At this time, the cooling device 4 and the cooling water pump 36 are operated to send the cooling water to the compressor unit 2. The compressed air generated in the compressor 6 is passed through the first cooler 11, the second cooler 12, and the third cooler 13, and heat is transferred from the compressed air to water by heat exchange between the compressed air and water. Thereby, simultaneously with cooling of compressed air, water is heated and becomes warm water.

  And the heated warm water is transferred via the warm water line L15. The hot water passes through the evaporator 21 of the binary power generation device 3 to heat and evaporate the working medium by heat exchange between the hot water and the working medium. So-called binary power generation is performed by the evaporated working medium. During this time, the controller 60 sequentially acquires the sensor values output from the first water temperature sensor 37, the second water temperature sensor 38, and the first flow rate sensor 39 (step S01). That is, the controller 60 acquires the temperature Tb from the first water temperature sensor 37, the temperature Ta from the second water temperature sensor 38, and the flow rate F from the first flow sensor 39. The controller 60 can acquire such information every predetermined time.

  The controller 60 receives the information output from the controller 30, and determines whether or not the binary power generation apparatus 3 is generating power (step S02). When it is determined that the binary power generation device 3 is not generating power (step S02: No), the controller 60 performs bypass control (step S04). In this bypass control, the controller 60 stops the hot water pump 31, fully closes the first valve 32, and fully opens the second valve 33. This bypass control stops binary power generation. The hot water does not flow into the evaporator 21 of the binary power generation device 3 but is returned to the cooling device 4 through the first return line L16. In the compressor system 1, the compressed air can be cooled while the power generation in the binary power generation device 3 is stopped.

  When it is determined that the binary power generation device 3 is generating power (step S02: Yes), the controller 60 determines whether to increase the temperature Ta (step S03).

  In step S03, the controller 60 determines whether or not to increase the temperature Ta using a predetermined formula. For example, the controller 60 stores in advance a threshold value related to the temperature of the cooling water flowing into the cooler of the compressor unit 2. This threshold is a water temperature that does not significantly reduce the performance of the compressor when the compressor 6 compresses air. This threshold value can be determined based on the temperature of the air sucked into the compressor 6, the pressure or flow rate of the compressed gas, or the like.

  If it is determined in step S03 that the temperature Ta is to be lowered (step S03: No), the controller 60 performs water temperature drop control (step S05). In this water temperature drop control, the controller 60 increases the flow rate of the hot water pump 31, opens the first valve 32 fully, and opens the second valve 33 (opens the second valve 33 somewhat). By this water temperature drop control, binary power generation is continuously performed, and the flow rate of hot water flowing through the hot water line L15 is increased. The amount of hot water returned directly to the cooling device 4 through the bypass line L14 increases.

  On the other hand, if it is determined in step S03 that the temperature Ta is to be increased (step S03: Yes), the controller 60 performs water temperature increase control (step S06). In this water temperature increase control, the controller 60 reduces the flow rate of the hot water pump 31, fully opens the first valve 32, and closes the second valve 33 (the second valve 33 is slightly closed). By this water temperature increase control, binary power generation is continuously performed, and the flow rate of the hot water flowing through the hot water line L15 is reduced. The amount of hot water returned directly to the cooling device 4 through the bypass line L14 decreases.

  By carrying out the above control, the controller 60 allows the temperature Ta to fall within a range that does not significantly reduce the performance of the compressor when the compressor 6 compresses air against the cooling water entering the cooler at the temperature Tb. Can be kept as high as possible. Thereby, the temperature of the hot water entering the evaporator 21 of the binary power generator 3 is increased. This means that the waste heat recovery efficiency from the compressor 6 is enhanced. For example, the temperature Tb of the cooling water supplied from the cooling device 4 is controlled to 30 to 40 ° C., and the temperature Ta of the hot water flowing into the evaporator 21 is controlled to 80 to 90 ° C. In addition, since the controller 60 performs a calculation regarding heat energy, the water temperature also depends on the state of the flow rate F.

  According to the compressor system 1 and the waste heat recovery power generation method described above, the heat of the compressed air is transmitted to water in the first cooler 11, the second cooler 12, and the third cooler 13. The water heated by the first cooler 11 and the second cooler 12 evaporates the binary power generator 3 through the first water outlet 2b and the second water outlet 2d, the hot water line L15, and the first water inlet 3a. Flows into the vessel 21. In the evaporator 21, the working medium is heated and evaporated. Thereby, the turbine generator 20 generates electric power. The binary power generator 3 uses the thermal energy of hot water below 100 ° C. to evaporate the working medium having a low boiling point, and generates power by the turbine generator 20. By combining the binary power generation device 3 that enables effective use of lower heat with the compressor 6, the heat energy of the compressed air that has been discarded in the past is recovered and used for power generation. Therefore, the efficiency of energy recovery from the compressor 6 is increased. Conventional systems have been difficult to apply to existing compressors. Existing compressors heated water and recovered thermal energy in the form of steam, which was insufficient to increase the efficiency of energy recovery. According to the compressor system 1 of the present disclosure in which the binary power generation device 3 is combined, the energy recovery efficiency is comprehensively improved. In addition, it is not necessary to change the configuration of the compressor 6, and the existing compressor 6 can be used.

  The compressor system 1 further includes a cooling device 4 that is a cooling source. The cooling device 4, the first cooler 11, the second cooler 12, and the third cooler 13 are connected via a supply line L10. The 1st cooler 11, the 2nd cooler 12, and the cooling device 4 are connected via the 1st return line L16. Therefore, the water used for heating the working medium in the evaporator 21 is sent to the cooling device 4 via the first return line L <b> 16 and is cooled in the cooling device 4. And the comparatively low temperature water produced with the cooling device 4 is sent to the 1st cooler 11, the 2nd cooler 12, and the 3rd cooler 13 via the supply line L10, and is used as a cooling water. .

  The amount of heat utilization related to the hot water discharged from the first cooler 11 and the second cooler 12 by opening and closing the first valve 32 provided in the hot water line L15 and the second valve 33 provided in the bypass line L14 The amount of bypass is adjusted. Thereby, the temperature of the water flowing into the first cooler 11, the second cooler 12, and the third cooler 13 is adjusted as desired. As a result, the heat exchange amount in the first cooler 11, the second cooler 12, and the third cooler 13 can be appropriately set.

  According to the cooling device 4 as one aspect of the cooling source, it is easy to cool the working medium in the binary power generation device 3. The cooling device 4 contributes to stable operation of the binary power generation device 3.

  The controller 60 controls the first valve 32, the second valve 33, and the hot water pump 31 (or any one or two of them), so that the first cooler 11, the second cooler 12, and the second cooler 31 3 The amount of water supplied to the cooler 13 and the evaporator 21 is adjusted. Since the supply amount of water is adjusted based on the temperature Tb of the water passing through the supply line L10, the heat exchange state in the first cooler 11, the second cooler 12, and the third cooler 13 can be controlled. . According to this, flexible control is possible.

  A first modification of the first embodiment is shown in FIG. The compressor system 1A shown in FIG. 3 is different from the compressor system 1 shown in FIG. 1 in that a compressor unit including a compressor 6A including a two-stage first-stage compressor 9a and a second-stage compressor 9b. The point provided with 2A, and the point provided with the connection part 5A which connects the cooling device 4 and two coolers (the 1st cooler 11 and the 2nd cooler 12). Thus, the same operation and effect as the compressor system 1 can be obtained also by the compressor system 1A in which the binary power generation device 3 is applied to the two-stage compression type compressor unit 2A.

  A second modification of the first embodiment is shown in FIG. The compressor system 1B shown in FIG. 4 is different from the compressor system 1 shown in FIG. 1 in that a compressor unit 2B including a compressor 6B including a first stage compression unit 9a is provided. It is the point provided with the connection part 5B which connects the cooling device 4 and one cooler (1st cooler 11). Thus, the same operation and effect as the compressor system 1 can be obtained also by the compressor system 1B in which the binary power generation device 3 is applied to the single-stage compression type compressor unit 2B.

  Next, a compressor system according to a second embodiment will be described with reference to FIGS. The compressor system 1C shown in FIG. 5 differs from the compressor system 1 shown in FIG. 1 in that a hot water tank 40 is provided in addition to the cooling device 4 as a cooling source, and the hot water tank 40 and the compressor unit. It is provided with a connecting portion 5C for connecting 2C. The hot water storage tank 40 is connected to the water outlet 4b of the cooling device 4 through the supply line L10. A temperature adjustment valve 44 is provided in the supply line L10. The hot water tank 40 is connected to the water inlet 4a of the cooling device 4 via the second return line L33. A return pump 43 is provided in the second return line L33. The supply line L <b> 10 is a line for supplying cooling water from the cooling device 4 to the hot water storage tank 40. The second return line L <b> 33 is a line for returning the water in the hot water tank 40 to the cooling device 4. The temperature adjustment valve 44 is controlled by the controller 60 and can adjust the supply amount of the cooling water supplied from the cooling device 4 to the hot water tank 40.

  In the connecting portion 5C, water is supplied from the hot water storage tank 40 to the first cooler 11 and the second cooler 12, and waste heat is supplied from the first cooler 11 and the second cooler 12 to the binary power generator 3. It is comprised so that it can be supplied. The hot water tank 40 is connected to the first water inlet 2a of the first cooler 11 and the second water inlet 2c of the second cooler 12 through the water line L30. A hot water pump 31 is provided in the water line L30. The first cooling line L11 and the second cooling line L12 merge at the downstream side of the first cooler 11 and the second cooler 12, and are connected to the hot water line L31. The hot water line L31 includes an evaporating heat exchange part L31a provided in the evaporator 21. Heat exchange is performed between the evaporation heat exchange unit L31a and the evaporation heat exchange unit L21a.

  A first valve 41 is provided in the hot water line L31. The opening degree of the first valve 41 can be adjusted under the control of the controller 60. The first water outlet 3b of the evaporator 21 of the binary power generator 3 and the hot water storage tank 40 are connected via a first return line L35. On the other hand, the first water outlet 2b of the first cooler 11 and the second water outlet 2d of the second cooler 12 are connected to the hot water storage tank 40 via the first return line L35. More specifically, the first cooling line L11 and the second cooling line L12 that merge on the downstream side of the first cooler 11 and the second cooler 12 are connected via a bypass line L32 that branches at a position different from the hot water line L31. And connected to the first return line L35. The first water outlet 2b of the first cooler 11 and the second water outlet 2d of the second cooler 12 are connected to the hot water storage tank 40 via a bypass line L32 and a first return line L35. A second valve 42 is provided in the bypass line L32. The opening degree of the second valve 42 can be adjusted by the control of the controller 60 described later. The compressor 6C is the same as the compressor 6 of the compressor system 1.

  In the waste heat recovery power generation method in the compressor system 1C, the controller 60 controls the hot water pump 31, the temperature adjustment valve 44, the return pump 43, the first valve 41, and the second valve 42. The water temperature control (thermal control) performed by the controller 60 is the same as the flow shown in FIG. In the bypass control in step S04, the controller 60 maintains the flow rate of the hot water pump 31 at a specified value, fully opens the second valve 42 and the temperature adjustment valve 44, and fully closes the first valve 41. In the water temperature drop control in step S05, the controller 60 increases the flow rate of the hot water pump 31, fully closes the second valve 42, fully opens the first valve 41, and opens the temperature adjustment valve 44 (temperature adjustment). Open valve 44 slightly). Thereby, the temperature of the water sent to the 1st cooler 11, the 2nd cooler 12, and the 3rd cooler 13 falls. In the water temperature increase control in step S06, the controller 60 decreases the flow rate of the hot water pump 31, fully closes the second valve 42, fully opens the first valve 41, and closes the temperature adjustment valve 44 (temperature adjustment). The valve 44 is closed a little). In the compressor system 1C, the water temperature in the hot water tank 40 is maintained at, for example, about 50 to 75 ° C. The controller 60 operates the return pump 43 so that the hot water tank 40 does not overflow regardless of the temperature.

  Also with the compressor system 1C using the hot water tank 40, the same operation and effect as the compressor system 1 of the first embodiment can be obtained.

  In the compressor system 1 </ b> C, a hot water storage tank 40 as one aspect of a cooling source is provided. The relatively low temperature water stored in the hot water storage tank 40 is sent to the first cooler 11, the second cooler 12, and the third cooler 13 via the water line L30, and is used as cooling water. The amount of heat utilization related to the hot water discharged from the first cooler 11 and the second cooler 12 by opening and closing the first valve 41 provided in the hot water line L31 and the second valve 42 provided in the bypass line L32. The amount of bypass is adjusted. According to the compressor system 1C provided with the hot water storage tank 40, the amount of heat can be easily managed.

  The controller 60 controls the temperature adjustment valve 44 to adjust the amount of water supplied to the hot water tank 40. Since the supply amount of water is adjusted based on the temperature of the water passing through the hot water line L31 or the water line L30, the water temperature in the hot water storage tank 40 is the first cooler 11, the second cooler 12, and the third cooler. 13 can be kept at a water temperature suitable for heat exchange. When the amount of stored water in the hot water storage tank 40 increases too much, the water can be returned to the cooling device 4 via the second return line L33.

  A first modification of the second embodiment is shown in FIG. The compressor system 1D shown in FIG. 6 is different from the compressor system 1C shown in FIG. 5 in that a compressor unit including a compressor 6D including a two-stage first-stage compressor 9a and a second-stage compressor 9b. The point provided with 2D and the point provided with the connection part 5D which connects the hot water storage tank 40 and two coolers (the 1st cooler 11 and the 2nd cooler 12). As described above, the compressor system 1D in which the hot water tank 40 and the binary power generation device 3 are applied to the two-stage compression type compressor unit 2D can provide the same operations and effects as those of the compressor system 1C.

  A second modification of the second embodiment is shown in FIG. The compressor system 1E shown in FIG. 7 is different from the compressor system 1C shown in FIG. 5 in that a compressor unit 2E including a compressor 6E including a first stage compression unit 9a is provided. This is a point provided with a connecting portion 5E that connects the hot water storage tank 40 and one cooler (first cooler 11). As described above, the compressor system 1E in which the hot water storage tank 40 and the binary power generator 3 are applied to the single-stage compression type compressor unit 2E can provide the same operations and effects as those of the compressor system 1C.

  Next, a compressor system according to a third embodiment will be described with reference to FIGS. The compressor system 1F shown in FIG. 8 is different from the compressor system 1C shown in FIG. 5 in that two binary power generators 3F and 3F are provided, and these binary power generators 3F and 3F and the compressor. It is the point provided with the connection part 5F which connects the unit 2C and the hot water storage tank 40. FIG. Thus, you may use several binary electric power generating apparatus 3F according to the number of coolers. Corresponding to the first cooler 11, a first binary power generator 3F is provided. Corresponding to the second cooler 12, a second binary power generator 3F is provided. The connecting portion 5F is configured such that water is supplied from the hot water tank 40 to the first cooler 11, and waste heat can be supplied from the first cooler 11 to the first binary power generation device 3F. . Further, the connecting portion 5F is configured such that waste heat can be supplied from the second cooler 12 to the second binary power generation device 3F. The compressor unit 2F and the compressor 6F are the same as the compressor unit 2C and the compressor 6C of the compressor system 1C. In the first binary power generation device 3F, a temperature adjustment valve 46 is provided in the bypass line L32.

  A cooling water line L50 is branched from the supply line L10 and the cooling water line L19. The cooling water line L50 is branched into a first cooling line L51 and a second cooling line L52. The second cooler 12 and the evaporator 21 of the second binary power generation device 3F are connected via a first cooling line L51. The first cooling line L51 includes a second heat exchange part L51a provided in the second cooler 12. The second cooling line L52 includes a third heat exchange part L52a provided in the third cooler 13. The first cooling line L51 and the second cooling line L52 merge at the downstream side of the second cooler 12 and the third cooler 13. The first cooling line L51 is provided with a hot water pump 53 and a third water temperature sensor 57 on the upstream side of the second cooler 12. A fourth water temperature sensor 58 and a second flow rate sensor 59 are provided in the first cooling line L51 and the second cooling line L52 that merge on the downstream side of the second cooler 12 and the third cooler 13.

  The first cooling line L51 is connected to the first water outlet 3b of the evaporator 21 on the upstream side of the second cooler 12. The first cooling line L51 is provided with a valve 50 on the upstream side of this connection point. The first cooling line L51 is connected to the first water inlet 3a of the evaporator 21 on the downstream side of the second cooler 12. The first cooling line L51 includes an evaporating heat exchange part L51b provided in the evaporator 21. The first cooling line L51 is provided with a third valve 51 on the downstream side of the second cooler 12. The opening degree of the valve 50 and the third valve 51 can be adjusted by the control of the controller 60. The second cooling line L <b> 52 is connected to the cooling device 4 on the downstream side of the third cooler 13. A second valve 52 is provided in the second cooling line L52. The opening degree of the second valve 52 can be adjusted under the control of the controller 60.

  In the waste heat recovery power generation method in the compressor system 1F, the controller 60 relates to the first binary power generation apparatus 3F, the cooling water temperature Tb1 from the first water temperature sensor 37, and the hot water temperature Ta1 from the second water temperature sensor 38. The flow rate F1 of hot water is acquired from the first flow rate sensor 39. The controller 60 obtains the temperature Tb2 of the cooling water from the third water temperature sensor 57, the temperature Ta2 of the hot water from the fourth water temperature sensor 58, and the flow rate F2 of the hot water from the second flow sensor 59 regarding the second binary power generation device 3F. To do. The controller 60 controls the hot water pump 31, the temperature adjustment valve 44, the temperature adjustment valve 46, the return pump 43, and the first valve 41 with respect to the first binary power generator 3F. The controller 60 controls the hot water pump 53, the valve 50, the second valve 52, and the third valve 51 with respect to the second binary power generation device 3F.

  With reference to FIG. 9, the waste heat recovery power generation method in the compressor system 1F will be described. The water temperature control (thermal control) performed by the controller 60 is the same as the flow shown in FIG. Steps S11 to S16 shown in FIG. 9 correspond to steps S01 to S06 shown in FIG. In the bypass control in step S14, the controller 60 maintains the flow rate of the hot water pump 31 at a specified value, fully opens the temperature adjustment valve 44 and the temperature adjustment valve 46, and fully closes the first valve 41. The controller 60 maintains the flow rate of the first valve 41 at a specified value, fully opens the valve 50 and the second valve 52, and fully closes the third valve 51.

  In the water temperature drop control in step S15, the temperature Ta1 and / or the temperature Ta2 is lowered. When lowering the temperature Ta1, the controller 60 increases the flow rate of the hot water pump 31, fully opens the first valve 41, opens the temperature adjustment valve 44 (opens the temperature adjustment valve 44 slightly), and adjusts the temperature adjustment valve. The opening of 46 is maintained at a specified value. Instead of this control, the controller 60 maintains the flow rate of the hot water pump 31 at a specified value, opens the first valve 41 fully, opens the temperature adjustment valve 44 (opens the temperature adjustment valve 44 slightly), and adjusts the temperature. The valve 46 may be closed (the temperature adjustment valve 46 may be closed somewhat). Thereby, the temperature of the water sent to the 1st cooler 11 falls. When the temperature Ta2 is lowered, the controller 60 increases the flow rate of the hot water pump 53, opens the third valve 51 fully, and opens the valve 50 and the second valve 52 (valves 50 and 2). 52 is slightly opened). Thereby, the temperature of the water sent to the 2nd cooler 12 falls.

  In the water temperature increase control in step S16, the temperature Ta1 and / or the temperature Ta2 is increased. When raising the temperature Ta1, the controller 60 decreases the flow rate of the hot water pump 31, fully opens the first valve 41, closes the temperature adjustment valve 44 (closes the temperature adjustment valve 44), and adjusts the temperature adjustment valve. The opening of 46 is maintained at a specified value. Instead of this control, the controller 60 maintains the flow rate of the hot water pump 31 at a specified value, fully opens the first valve 41, closes the temperature adjustment valve 44 (closes the temperature adjustment valve 44), and adjusts the temperature. The valve 46 may be open (the temperature adjustment valve 46 may be opened somewhat). Thereby, the temperature of the water sent to the 1st cooler 11 rises. When the temperature Ta2 is increased, the controller 60 decreases the flow rate of the hot water pump 53, fully opens the third valve 51, and fully closes the valve 50 and the second valve 52. Thereby, the temperature of the water sent to the 2nd cooler 12 rises.

  In the above control, the controller 60 operates the return pump 43 so that the hot water tank 40 does not overflow regardless of the temperature.

  The compressor system 1F including the plurality of binary power generation devices 3F can also provide the same operations and effects as the compressor system 1 of the first embodiment and the compressor system 1C of the second embodiment.

  A first modification of the third embodiment is shown in FIG. The compressor system 1G shown in FIG. 10 is different from the compressor system 1F shown in FIG. 8 in that a compressor unit including a compressor 6G including a two-stage first-stage compressor 9a and a second-stage compressor 9b. The point provided with 2G, and the point provided with the connection part 5G which connects the hot water storage tank 40 and two coolers (the 1st cooler 11 and the 2nd cooler 12). As described above, the compressor system 1G in which the hot water storage tank 40 and the two binary power generation devices 3F and 3F are applied to the two-stage compression type compressor unit 2G can provide the same operations and effects as those of the compressor system 1F.

  The embodiments of the present disclosure have been described above, but the present invention is not limited to the above embodiments. For example, the amount of water in the hot water storage tank 40 may be adjusted by opening or closing a valve without providing the return pump 43 in the second return line L33 of the hot water storage tank 40. In this case, the hot water tank 40 is provided at a position higher than at least the cooling device 4.

  The present invention is not limited to the case where compressed air is generated by the compressor 6. The compressor 6 may compress a gas other than air.

1, 1A, 1B, 1C, 1D, 1F, 1G Compressor system 2, 2A, 2B, 2C, 2D, 2F, 2G Compressor unit 2a First water inlet (water inlet)
2b 1st water outlet (water outlet)
2c Second water inlet (water inlet)
2d Second water outlet (water outlet)
2e 3rd water inlet (water inlet)
2f 3rd water outlet (water outlet)
3, 3F Binary power generator 3a First water inlet (water inlet)
3b 1st water outlet (water outlet)
3c 2nd water inlet (water inlet)
3d 2nd water outlet (water outlet)
4 Cooling device 5, 5A, 5B, 5C, 5D, 5F, 5G Connection part 6, 6A, 6B, 6C, 6D, 6F, 6G Compressor 11 1st cooler (cooler)
12 Second cooler (cooler)
13 Third cooler (cooler)
20 Turbine generator (generator)
21 Evaporator 22 Condenser 31 Hot Water Pump 32 First Valve 33 Second Valve 40 Hot Water Tank 44 Temperature Adjustment Valve 51 Third Valve 52 Second Valve 53 Hot Water Pump 60 Controller L10 Supply Line (Water Line)
L11 First cooling line L12 Second cooling line L14 Bypass line L15 Hot water line L16 First return line L20 Medium circulation line L30 Water line L31 Hot water line L32 Bypass line L33 Second return line L35 First return line L51 First cooling line L52 Second cooling line

Claims (4)

A compressor for generating compressed gas;
A cooler that transfers heat from the compressed gas to the water by heat exchange between the compressed gas generated in the compressor and water;
Binary power generation comprising: an evaporator that heats the working medium by heat exchange between the water heated by the cooler and the working medium; and a generator that generates power using the working medium evaporated and heated by the evaporator Equipment ,
A cooling source capable of cooling the water flowing out of the evaporator ,
The cooler includes a water outlet through which the water flowing out from the cooler passes, and a water inlet through which the water flowing into the cooler passes ,
The evaporator of the binary power generation device includes a water inlet through which the water flowing into the evaporator passes, and a water outlet through which the water flowing out from the evaporator passes ,
The water outlet of the cooler and the water inlet of the evaporator are connected via a hot water line ,
The cooling source and the water inlet of the cooler are connected via a water line, the water outlet of the evaporator and the cooling source are connected via a first return line,
The hot water line or the water line is provided with a hot water pump for passing the water through the evaporator,
The hot water line is provided with a first valve for adjusting a heat utilization amount based on flowing the water from the water outlet of the cooler into the evaporator,
The cooling source includes a hot water tank connected to the water inlet of the cooler via the water line,
The cooler is connected to the hot water storage tank via a bypass line and the first return line that branch between the water outlet of the cooler and the first valve,
The compressor system , wherein the bypass line is provided with a second valve for adjusting a bypass amount based on returning the water from the water outlet of the cooler to the hot water storage tank . The binary power generation device includes a medium circulation line for circulating the working medium, and a condenser that cools the working medium by heat exchange between the working medium and the water, and the medium circulation line includes the evaporation medium. Through the condenser, the generator and the condenser,
The compressor system according to claim 1 , wherein the cooling source further includes a cooling device connected to the condenser to cool the water. A controller for obtaining a temperature of the water passing through the hot water line or the water line;
The compressor system according to claim 1 or 2 , wherein the controller controls the first valve, the second valve, or the hot water pump based on the temperature of the hot water line or the water passing through the water line. . A controller for obtaining a temperature of the water passing through the hot water line or the water line;
The hot water storage tank and the cooling device are connected via a supply line for supplying the water from the cooling device to the hot water storage tank, and are used for returning the water from the hot water storage tank to the cooling device. Connected through two return lines,
The supply line is provided with a temperature adjustment valve capable of adjusting the supply amount of the water supplied from the cooling device to the hot water storage tank,
The compressor system according to claim 2 , wherein the controller controls the temperature adjustment valve based on the temperature of the hot water line or the water passing through the water line.

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