JP2015121395A - Cold supply system, cogeneration system, and control method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cold supply system, a cogeneration system, and a control method capable of improving maintainability while improving recovery efficiency of waste heat from a prime mover for use in power generation.SOLUTION: A cold supply system includes: an absorption refrigerating machine 20 driven with exhaust gas discharged from an engine body 12 for driving a generator 13 and hot water circulated via the engine body 12 for cooling the engine body 12 used as a heating source; and an exhaust-gas-hot-water heat exchanger 30 provided outside of the absorption refrigerating machine 20, and implementing heat exchange between the exhaust gas passing through a downstream exhaust gas pipe 17 via the absorption refrigerating machine 20 and the hot water passing through a hot water pipe 18 spreading from the engine body 12 to the absorption refrigerating machine 20.

Description

  The present invention relates to a cold supply system driven by exhaust heat or the like during power generation, a combined heat and power supply system, and control methods thereof.

  There has been proposed a cogeneration system (cogeneration system) that obtains electric power from a power generation unit that drives a generator by an engine or the like and uses the exhaust heat from the power generation unit to efficiently use energy.

  As a technique related to such a cogeneration system, for example, in Patent Document 1 (Japanese Patent Laid-Open No. 2001-183027), a power generation unit and an absorption chiller are combined to generate electric power in the power generation unit. An apparatus is disclosed in which exhaust gas from a power generation unit is led to a high-pressure regenerator, a high re-inlet heat exchanger, a low re-auxiliary heat exchanger, and a low re-inlet heat exchanger in an absorption refrigerator to recover heat to a low temperature.

JP 2001-183027 A

  By the way, the exhaust gas generated from the power generation unit may contain corrosive components such as nitrogen oxides and sulfur oxides caused by the purity of the fuel and the state of combustion in addition to the water vapor component generated by the combustion of hydrocarbons. is there. Therefore, when the exhaust gas from the power generation unit is heat-recovered to a low temperature with an absorption chiller as in the above prior art, the water vapor component is condensed due to the temperature drop of the exhaust gas and adheres as water droplets to the inner surface of the pipe through which the exhaust gas passes. Further, it is considered that the corrosive components of the exhaust gas are dissolved in the water droplets, thereby causing corrosion in a device such as a heat exchanger.

  In addition, when replacing the heat exchanger inside the absorption chiller for reasons such as corrosion, the deterioration of the entire absorption chiller is prevented due to internal corrosion caused by the reaction between oxygen in the atmosphere and the absorption liquid. In addition, it is necessary to recover the absorption liquid in the heat exchanger, and there is a problem that the exchange work becomes complicated and difficult.

  The present invention has been made in view of the above, and provides a cooling / heating supply system, a combined heat and power system, and a control method capable of improving maintainability while improving the efficiency of recovering exhaust heat from a prime mover used for power generation. The purpose is to provide.

  In order to achieve the above object, the present invention uses a generator driven by a prime mover, exhaust gas discharged from the prime mover, and hot water circulated through the prime mover to cool the prime mover as heat sources. A heat-driven refrigerator that is driven, an exhaust gas that is disposed outside the heat-driven refrigerator and passes through an exhaust gas passage on the downstream side via the heat-driven refrigerator, and the heat-driven refrigerator from the prime mover An exhaust gas hot water heat exchanger that exchanges heat with warm water passing through a warm water flow path to the machine is provided.

  ADVANTAGE OF THE INVENTION According to this invention, maintainability can be improved, aiming at the improvement of the collection | recovery efficiency of the waste heat from the motor | power_engine used for electric power generation.

It is a figure showing roughly the whole composition of the cold-heat generation type combined heat and power supply system concerning one embodiment of the present invention. It is a figure which shows roughly the structural example of an absorption refrigerator. It is a functional block diagram which shows the structure of a control apparatus with the peripheral function. It is a figure which shows the content of the operation instruction | indication to each part of the cold-heat generation type cogeneration system in each set operation mode.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram schematically showing an overall configuration of a cold heat generation type combined heat and power supply system according to the present embodiment.

  In FIG. 1, the cold heat generation type combined heat and power supply system 10 controls the operation of the engine power generation unit 100, the cold / hot water supply unit 200 (cold heat supply system), the cooling tower 90, and the cold heat generation type combined heat and power supply system 10. The apparatus 35 is schematically configured.

  The engine power generation unit 100 includes an engine main body 12 as a prime mover that is driven using fuel supplied from a fuel supply unit (fuel tank or the like) (not shown) via a fuel supply path 15, and a generator driven by the engine main body 12. 13 and an engine power generation unit 11 having a heat radiator 14 for radiating engine oil or the like with outside air 19.

  The engine body 12 is provided with a hot water pipe (hot water flow path) 18 for circulating cooling water (hot water) for engine cooling between the engine main body 12 and the cold / hot water supply unit 200. The hot water pipe 18 has a flow path of hot water from the cold / hot water supply unit 200 to the engine body 12 and a flow path of hot water from the engine body 12 to the cold / hot water supply unit 200. The engine body 12 is cooled by hot water supplied from the cold / hot water supply unit 200 side via the hot water pipe 18. The hot water supplied from the cold / hot water supply unit 200 side to the engine main body 12 via the hot water pipe 18 is heated by the heat generated by driving the engine main body 12 and the temperature rises, and the hot / warm water supply is supplied via the hot water pipe 18. Return to section 200.

  The generator 13 generates power by being driven by the engine body 12. The electric power generated by the generator 13 is transmitted to the demand side via the power transmission path 16.

  The radiator 14 is thermally connected to a circulation path of engine oil or the like used in the engine body 12, and the engine oil or the like is cooled by radiating heat through the radiator 14. The radiator 14 includes a blower fan 14 a, and the cooling effect is enhanced by taking outside air 19 by the blower fan 14 a and exhausting it through the radiator 14.

  High-temperature exhaust gas generated by driving the engine body 12 is sent to the cold / hot water supply unit 200 side through the exhaust gas pipe 17 connected to the engine body 12.

  The cold / hot water supply unit 200 is driven by heat using the exhaust gas supplied from the engine power generation unit 100 via the exhaust gas pipe 17 and the heat of hot water supplied from the engine power generation unit 100 via the hot water pipe 18 as heat sources. Absorption refrigerator 20 as a type refrigerator, exhaust gas disposed outside absorption refrigerator 20 and passing through exhaust gas pipe 17 on the downstream side through absorption refrigerator 20, and absorption refrigerator from engine body 12 An exhaust gas hot water heat exchanger 30 for exchanging heat with hot water passing through a hot water pipe 18 to 20 is roughly provided.

  The absorption chiller 20 uses, as heat sources, exhaust gas supplied from the engine body 12 via the exhaust gas pipe 17 and hot water heated by the engine body 12 and the exhaust gas hot water heat exchanger 30 and supplied via the hot water pipe 18. In addition, the cooling water supplied from the cooling tower 90 via the cooling water pipe 95 by the cooling water pump 91 is used as a cooling source, and the water (cold water before cooling) supplied from the cooling water pump 21 via the cold water pipe 25 is used. It is cooled and supplied to the demand side as cold water (water after cooling). A chilled water temperature sensor 25 a that detects the chilled water temperature supplied to the demand side is provided on the downstream side of the chilled water pipe 25 in the absorption refrigerator 20. The detection result of the cold water temperature sensor 25 a is sent to the control device 35.

  The hot water heat recovery unit 23 is provided on the hot water pipe 18 and recovers thermal energy used in the absorption refrigerator 20 from the hot water sent from the engine power generation unit 100 via the hot water pipe 18 (details will be described later). The hot water whose thermal energy has been recovered by the hot water heat recovery unit 23 is sent again to the engine power generation unit 100 via the hot water pipe 18. A flow path from the cold / hot water supply unit 200 of the hot water pipe 18 to the engine main body 12 is provided with a hot water pump 31 for sending out hot water, and between the engine main body 12 and the absorption refrigerator 20 by the operation of the hot water pump 31. Hot water is circulated.

  From the hot water pipe 18 on the upstream side of the absorption refrigerator 20 and the downstream side of the exhaust gas hot water heat exchanger 30 in the hot water pipe 18 that circulates hot water between the engine body 12 and the absorption refrigerator 20, At the branch part of the external heat dissipating hot water bypass pipe 65 for guiding the hot water to the hot water pipe 18 on the downstream side of the absorption refrigerator 20 and the hot water pipe 18 on the upstream side of the absorption refrigerator 20 and the external heat dissipating hot water bypass pipe 65. And an external heat radiating three-way valve 18a that adjusts the flow rate of hot water in the hot water pipe 18 and the external heat radiating hot water bypass pipe. Is provided with an external heat radiating heat exchanger 60 that cools the hot water with the cooling water supplied through the cooling water pipe 96. The cooling water is supplied from the cooling tower 90 to the external heat radiating heat exchanger 60 through the cooling water pipe 96 by the operation of the cooling water pump 91, and is used for cooling the hot water by the external heat radiating heat exchanger 60. Then, it is sent again to the cooling tower 90 and circulated.

  The cooling tower 90 is for cooling the cooling water used in the combined heat and power supply system 10. The cooling tower 90 includes a cooling water pipe 95 for circulating the cooling water between the absorption chiller 20 and a cooling water pipe 96 for circulating the cooling water between the heat exchanger 60 for heat radiation. Are connected in parallel, and cooling water is supplied by the operation of the cooling water pump 91. On the upstream side and downstream side of the cooling tower 90, an on-off valve 90a and an on-off valve 90b are provided.

  The hot water pipe 18 has a hot water pipe 18 upstream of the absorption refrigerator 20 and downstream of the exhaust gas hot water heat exchanger 30 in the hot water pipe 18 that circulates hot water between the engine body 12 and the absorption refrigerator 20. To the hot water pipe 18 on the downstream side of the absorption chiller 20, the hot water bypass pipe 75 for heating the secondary hot water, the hot water pipe 18 on the upstream side of the absorption chiller 20, and the hot water bypass pipe for heating the secondary hot water. 75, a secondary hot water heating three-way valve 18b that adjusts the flow rate of the hot water in the hot water pipe 18 and the hot water bypass pipe 75 for heating the secondary hot water is provided for the secondary hot water heating. The hot water bypass pipe 75 is provided with a secondary hot water heating heat exchanger 70 that heats the secondary hot water supplied to the hot water load system on the demand side. The secondary hot water is supplied to the secondary hot water heating heat exchanger 70 via the secondary hot water pipe 97 by the operation of the secondary hot water pump 71, and is heated by the secondary hot water heating heat exchanger 70. , Sent to the hot water load system on the demand side. On the downstream side of the secondary hot water heating heat exchanger 70 of the secondary hot water pipe 97, a secondary hot water temperature sensor 76a for detecting the temperature of the secondary hot water supplied to the demand side is provided. The detection result of the secondary hot water temperature sensor 76 a is sent to the control device 35.

  An upstream side of a branching section of the hot water pipe 18 with the absorption refrigerator 20 (in other words, the hot water heat recovery section 23), a branching section with the external heat radiating hot water bypass pipe 65, and a branching section with the secondary hot water heating hot water bypass pipe 75; In addition, a hot water temperature sensor 18 c that detects the temperature of the hot water supplied from the exhaust gas hot water heat exchanger 30 is provided on the downstream side of the exhaust gas hot water heat exchanger 30. In addition, on the downstream side of the merged portion with the absorption refrigerator 20 of the hot water pipe 18 (in other words, the warm water heat recovery unit 23), the hot water bypass pipe 65 for external heat dissipation, and the secondary hot water pipe 97, A hot water temperature sensor 18d for detecting the temperature of the hot water supplied to the engine body 12 is provided. The detection results of the hot water temperature sensors 18 c and 18 d are sent to the control device 35.

  The exhaust gas heat recovery unit 22 is provided on the exhaust gas pipe 17 and recovers thermal energy used in the absorption refrigeration machine 20 from the exhaust gas discharged from the engine power generation unit 100 and sent through the exhaust gas pipe 17 (details later). Description). The exhaust gas whose thermal energy has been recovered by the exhaust gas heat recovery section 22 is sent further downstream through the exhaust gas pipe 17, subjected to appropriate processing, and discharged.

  The cold / hot water supply unit 200 includes an exhaust gas main damper 17a that is provided in an exhaust gas pipe 17 between the engine body 12 and the absorption chiller 20 and adjusts the flow rate of the exhaust gas sent to the absorption chiller 20, and an engine. An exhaust gas bypass pipe 55 for guiding exhaust gas from the exhaust gas pipe 17 between the main body 12 and the exhaust gas main damper 17a to the exhaust gas pipe 17 on the downstream side of the exhaust gas hot water heat exchanger 30, and an exhaust gas bypass pipe 55 are provided. An exhaust gas bypass damper 55a for adjusting the flow rate of the exhaust gas passing through is provided. The operations of the exhaust gas main damper 17a and the exhaust gas bypass damper 55a are controlled by the control device 35 along with the operation of the absorption refrigerator 20.

  FIG. 2 is a diagram schematically showing a configuration example of the absorption refrigerator according to the present embodiment.

  In FIG. 2, the absorption chiller 20 includes an exhaust gas heat recovery unit 22, a hot water heat recovery unit 23, an evaporator 26, an absorber 27, and a condenser 28.

  The evaporator 26 is for cooling cold water by evaporating the refrigerant liquid. An evaporation heat transfer tube configured as a part of the cold water piping 25 is passed through the evaporator 26. Refrigerant liquid 26c stays at the bottom of the evaporator 26, and is carried by the operation of the refrigerant pump 26a and dropped (sprayed) onto the surface of the evaporation heat transfer tube from the spray tube 26b disposed above the evaporation heat transfer tube. The The refrigerant liquid on the surface of the evaporation heat transfer tube acts to take heat from the cold water passing through the evaporation heat transfer tube (cold water piping 25) via the evaporation heat transfer tube when evaporating. Thereby, the cold water which passes the inside of the cold water piping 25 is cooled. The refrigerant liquid that has flowed down without evaporating from the surface of the evaporation heat transfer tube stays at the bottom of the evaporator 26, is carried to the spray tube 26b by the refrigerant pump 26a, and is dropped again.

  The absorber 27 is for absorbing the refrigerant (refrigerant vapor) evaporated by the evaporator 26. An absorption heat transfer tube configured as a part of the cooling water pipe 95 is passed through the absorber 27. The absorption heat transfer tube is disposed so as to pass through the absorber 27 and then through the condenser 28 and again through the absorber 27. From the spray tube 27b disposed above the absorption heat transfer tube, the exhaust gas heat recovery unit 22 as a high temperature regenerator and the solution (absorbed liquid) heated and concentrated by the low temperature regenerator 24 are dropped onto the surface of the absorption heat transfer tube ( Sprayed). The solution on the surface of the absorption heat transfer tube absorbs the refrigerant vapor from the evaporator 26 while being cooled by the cooling water passing through the absorption heat transfer tube. Thereby, the refrigerant | coolant vapor pressure inside the evaporator 26 is hold | maintained at the pressure required in order to evaporate a refrigerant | coolant liquid from the surface of an evaporation heat exchanger tube. A solution 27c that has absorbed refrigerant (refrigerant vapor) stays at the bottom of the absorber 27, and is sent to the low-temperature regenerator 24 by the solution pump 27a via the low-temperature solution heat exchanger 29a arranged in the solution piping system. Alternatively, it is sent to the exhaust gas heat recovery unit 22 (high temperature regenerator) via the low temperature solution heat regenerator 29a and the high temperature solution heat exchanger 29b arranged in the solution piping system.

  The exhaust gas heat recovery unit 22 is a high-temperature regenerator, and heats the solution by heating the solution (absorbing liquid) that has absorbed the refrigerant to evaporate and separate the refrigerant (that is, separate the refrigerant from the solution as refrigerant vapor). Concentrate. High-temperature exhaust gas 11 a is passed through the exhaust gas heat recovery unit 22 through the exhaust gas pipe 17. In the exhaust gas heat recovery unit 22, the solution is heated and concentrated by the heat of the exhaust gas 11a through the heat transfer structure 22a. The solution concentrated in the exhaust gas heat recovery unit 22 merges with the solution from the low temperature regenerator 24 via the high temperature solution heat exchanger 29b, and is sent to the spray tube 27b of the absorber 27 via the low temperature solution heat regenerator 29a. It is done. Further, the refrigerant vapor generated when the solution is heated and concentrated in the exhaust gas heat recovery unit 22 is sent to the condenser 28 via the heat transfer tube 24 a passed through the low temperature regenerator 24.

  Similar to the high temperature regenerator, the low temperature regenerator 24 heats and concentrates the solution by heating the solution that has absorbed the refrigerant and evaporating and separating the refrigerant. Inside the low-temperature regenerator 24, a heat transfer tube 24 a through which refrigerant vapor generated in the exhaust gas heat recovery unit 22 passes and a heat transfer tube 23 a configured as a part of the hot water pipe 18 are passed. From the spray tube 24b disposed above the heat transfer tubes 23a and 24a, the solution sent from the absorber 27 via the low-temperature solution heat exchanger 29a is dropped (sprayed) onto the surfaces of the heat transfer tubes 23a and 24a. .

  The solution on the surface of the heat transfer tube 23a is heated and concentrated by hot water passing through the heat transfer tube 23a and flows down, and stays at the bottom of the low temperature regenerator 24 (solution 24c). The heat transfer tube 23 a collects the thermal energy of the hot water and constitutes the hot water heat recovery unit 23. The solution on the surface of the heat transfer tube 24a is heated and concentrated by the refrigerant vapor passing through the heat transfer tube 24a, flows down, and stays at the bottom of the low temperature regenerator 24 (solution 24c). The refrigerant vapor passing through the heat transfer tube 24 a is cooled to a solution on the surface of the heat transfer tube 24 a and sent to the condenser 28. The solution 24c retained at the bottom of the low-temperature regenerator 24 merges with the solution heated and concentrated in the high-temperature regenerator (exhaust gas heat recovery unit 22), and the dispersion tube 27b of the absorber 27 is passed through the low-temperature solution heat regenerator 29a. Sent to.

  The condenser 28 is for condensing the refrigerant (refrigerant vapor) evaporated in the low temperature regenerator 24. A heat transfer pipe 28 a configured as a part of the cooling water pipe 95 is passed through the condenser 28. From above the heat transfer tube 28a, the refrigerant (refrigerant vapor) cooled by the heat transfer tube 24a of the low-temperature regenerator 24 is dropped (sprayed) onto the surface of the heat transfer tube 28a. The refrigerant on the surface of the heat transfer tube 28a is cooled and condensed by the cooling water passing through the heat transfer tube 28a, flows down and stays at the bottom of the condenser 28 (refrigerant liquid 28c). The refrigerant liquid 28c staying at the bottom of the condenser 28 is sent to the evaporator 26 and dropped onto the evaporation heat transfer pipe together with the refrigerant liquid dropped from the spray pipe 26b.

  FIG. 3 is a functional block diagram showing the configuration of the control device together with its peripheral functions.

  In FIG. 3, the control device 35 controls the entire operation of the cold heat generation type combined heat and power supply system 10, and includes an operation control unit 35 a that controls the cold heat generation type combined heat and power supply system 10 according to the set operation mode. .

  Detection results of the cold water temperature sensor 25a, the secondary hot water temperature sensor 76a, and the hot water temperature sensors 18c and 18d and a setting result (detection signal) by the operation setting unit 36 are input to the operation control unit 35a. The operation control unit 35a outputs operation instructions (instruction signals) to the exhaust gas damper 17a, the exhaust gas bypass damper 55a, the external heat radiation three-way valve 18a, the secondary hot water heating three-way valve 18b, and the absorption refrigerator 20. Has been.

  The operation setting unit 36 sets the operation mode of the cold heat generation type thermoelectric supply system 10 to any one of the cold heat generation operation, the cold heat stop operation, and the equipment stop by the operation of the operator, and outputs the setting result to the operation control unit 35a. Further, in each operation mode of the cold heat generation operation and the cold heat stop operation, hot water stop and hot water generation can be set, respectively, and these setting results are also output to the operation control unit 35a.

  FIG. 4 is a diagram showing the contents of operation instructions to each part of the cold-heat generation combined heat and power supply system in each set operation mode.

  In FIG. 4, the setting when operating the absorption refrigerator 20 (when operating the pumps 26a, 27a, etc.) is indicated by “ON”, and the setting when stopping is indicated by “OFF”. In addition, the setting of the external heat dissipation three-way valve 18a when hot water is passed through the absorption refrigerator 20 side is indicated by “open”, and the external heat dissipation three-way valve 18a when warm water is passed through the external heat dissipation hot water bypass pipe 65 side is indicated. The setting is shown as “Closed”. Similarly, the setting of the secondary hot water heating three-way valve 18b when warm water is passed through the absorption refrigerator 20 side is indicated by “open”, and the secondary when warm water is passed through the secondary warm water heating warm water bypass pipe 75 side. The setting of the three-way valve 18b for warm water heating is indicated by “closed”.

  In addition, in the exhaust gas pipe 17, the setting of the exhaust gas main damper 17a when the exhaust gas is passed to the absorption refrigerator 20 side is indicated by "open", and the case where it is shut off is indicated by "closed". Similarly, in the exhaust gas bypass pipe 55, the setting of the exhaust gas bypass damper 55a when the exhaust gas is passed downstream is indicated by “open”, and the case where it is shut off is indicated by “closed”.

  Here, the detail of operation | movement in each operation mode of the cold-heat generation type cogeneration system 10 in a present Example is demonstrated.

  The cold heat generation type combined heat and power supply system 10 is a cold heat generating operation in which generation and supply of electric power and generation and supply of cold heat (that is, supply of cold water) at the same time, and generation and supply of electric power, but no generation of cold heat. There are three types of operation modes: stop operation and device stop to stop the operation of the device body. Furthermore, in each of the cold generation operation and the cold stop operation, hot water is generated simultaneously with the supply of electric power and cold water. It has a function to supply.

  During operation of the cold heat generation combined heat and power supply system 10, as a common operation, fuel is supplied to the engine power generation unit 11 of the engine power generation unit 100 via the fuel supply path 15 and started. At this time, in the engine power generation unit 11, electric power generated by driving the generator 13 connected to the engine body 12 is transmitted to the demand side via the power transmission path 16. On the other hand, warm water as jacket cooling water is supplied to the engine body 12 via a warm water pipe 18. The warm water cools the engine body 12 and rises in temperature and flows out of the engine through the warm water pipe 18. At this time, since the heat of the oil cooler is low and cannot be recovered by hot water, it is radiated from the radiator 14 to the outside air 19.

  When the operation mode is set to cold heat generation operation and hot water stop, as shown in FIG. 4, the absorption chiller 20 is turned on, and the external heat radiation three-way valve 18 a is heated to the engine power generation unit 11. Control (opening control) is performed based on the temperature (detection results of the hot water temperature sensors 18c and 18d), and the secondary hot water heating three-way valve 18b is closed. The exhaust gas main damper 17a and the exhaust gas bypass damper 55a are controlled based on the temperature of the cold water supplied from the absorption chiller 20 (the detection result of the cold water temperature sensor 25a). In the case of cold heat generation), the former is open and the latter is closed.

  During operation of the engine power generation unit 11, exhaust gas of about 500 to 600 ° C. is generated. The exhaust gas is guided to the exhaust gas heat recovery unit 22 of the absorption refrigeration machine 20 through the exhaust gas main damper 17a in the exhaust gas pipe 17. The exhaust gas heat recovery unit 22 is a high-temperature regenerator of the absorption refrigerator 20, and the heat of the exhaust gas recovered by the exhaust gas heat recovery unit 22 is equivalent to the input of the double-effect absorption refrigerator for the generation of cold. It is utilized with high efficiency.

  The exhaust gas whose heat has been released by the exhaust gas heat recovery unit 22 of the absorption chiller 20 is reduced in temperature to about 150 to 200 ° C., and then the exhaust gas hot water heat exchange disposed outside the absorption chiller 20 by the exhaust gas pipe 17. Guided to vessel 30. The exhaust gas hot water heat exchanger 30 is supplied with hot water, which is used as jacket cooling water in the engine body 12 and whose temperature has risen, via a hot water pipe 18. In the exhaust gas hot water heat exchanger 30, by exchanging heat between the exhaust gas and hot water, the exhaust gas is cooled to about 100 to 120 ° C. and becomes a low temperature exhaust gas, which is discharged to the outside through the exhaust gas pipe 18. The hot water rises in temperature and is supplied to the hot water heat recovery unit 23 of the absorption refrigerator 20 through the three-way valves 18a and 18b by the hot water pipe 17.

  The hot water heat recovery unit 23 of the absorption refrigerator 20 constitutes a low temperature regenerator 24 of the absorption refrigerator 20, and the thermal energy of the hot water recovered by the hot water heat recovery unit 23 is It is used with the same thermal efficiency as the input of a single-effect absorption refrigerator. Although the thermal efficiency in this case is low compared with the thermal efficiency in the case of the thermal energy of the exhaust gas recovered by the exhaust gas heat recovery unit 22, it is utilized very effectively.

  In the absorption chiller 20, the cooling water 95 supplied from the cooling tower 90 by the cooling water pump 91 using the exhaust gas from the engine body 12 and the hot water 18 reheated by the exhaust gas hot water heat exchanger 30 as a heat source. As a cooling source, the cold water fed by the cold water pump 21 is cooled and supplied as cold water 25 to the demand side.

  Thus, in the basic state (when the maximum cold heat is generated), the exhaust gas main damper 17a is open and the exhaust gas bypass damper 55a is closed. Accordingly, the entire amount of the exhaust gas is sent to the absorption refrigeration machine 20 and the exhaust gas hot water heat exchanger 30 via the exhaust gas pipe 17, and heat is recovered in each.

  When the cooling load is smaller than the maximum amount of cold heat generated by the absorption chiller 20, the temperature of the chilled water supplied to the demand side from the absorption chiller 20 via the chilled water pipe 25 (detection result of the chilled water temperature sensor 25a) is predetermined. In this case, there is a possibility that the absorption refrigerator 20 may malfunction.

  Therefore, in this case, the exhaust gas bypass damper 55a provided in the exhaust gas bypass pipe 55 bypassed from the exhaust gas pipe 17 is controlled based on the temperature of the cold water (the detection result of the cold water temperature sensor 25a). That is, when the temperature of the cold water passing through the cold water pipe 25 becomes lower than a predetermined target value, the exhaust gas bypass damper 55a is opened to bypass the exhaust gas to the exhaust gas bypass passage 55, and the absorption refrigerator 20 is used as a heat source. The flow rate of the supplied exhaust gas is decreased, and the cold heat generation capacity of the absorption chiller 20 is decreased. Thus, the occurrence of problems in the absorption chiller 20 can be prevented by controlling the exhaust gas bypass damper 55a so that the temperature of the cold water passing through the cold water pipe 25 becomes a predetermined target value.

  Further, even when the exhaust gas bypass damper 55a is fully opened, when the temperature of the cold water becomes lower than a predetermined target value, the exhaust gas main damper 17a that is fully open is controlled to close as the cold water temperature decreases. By doing (that is, opening degree control so that the opening degree becomes smaller), the flow rate of exhaust gas supplied as a heat source of the absorption chiller 20 is further reduced, and the cold heat generation capacity and the supply temperature of cold water are controlled. .

  When the temperature of the cold water becomes lower than a predetermined target value even when the exhaust gas bypass damper 55a is fully opened, the exhaust gas main damper 17a is fully closed instead of controlling the opening degree, and the temperature of the cold water is higher than the predetermined target value. Also, when the difference becomes higher than a certain difference, the control may be performed to fully open again.

  Further, the external heat radiation hot water bypass pipe 65 and the external heat radiation three-way valve 18a connected to the hot water pipe 18 are temperatures of hot water supplied to the engine power generation unit 11 as cooling water for the engine body 12 (detection by the hot water temperature sensor 18d). As a result, the opening degree of the external heat radiating three-way valve 18a is controlled based on the temperature of the hot water so that the upper limit temperature required for cooling the engine body 12 does not exceed the upper limit temperature. That is, when the temperature of the hot water supplied to the engine main body 12 rises, a part of the hot water sent from the engine main body 12 via the hot water pipe 18 through the hot water heat exchanger 30 is passed through the external heat radiating hot water bypass pipe 65. The external heat radiating heat exchanger 60 is cooled by the cooling water guided to the external heat radiating heat exchanger 60 and returned to the upstream side of the engine main body 12 of the hot water pipe 18. To control.

  Furthermore, when the exhaust gas in the exhaust gas pipe 17 is completely bypassed to the exhaust gas bypass pipe 55, when the temperature of the cold water becomes lower than a predetermined target value, the opening degree of the external heat radiation three-way valve 18a is set based on the cold water temperature. By controlling the opening so as to adjust, the flow rate of hot water supplied to the absorption chiller 20 may be controlled to suppress the ability to generate cold. Even in this case, since the hot water led to the external heat radiating hot water bypass pipe 65 is cooled by the cooling water 96, it is prevented that the engine body 12 is cooled.

  When the operation mode is set to cold heat generation operation and hot water generation, as shown in FIG. 4, it is absorbed via the hot water pipe 18 by controlling the opening degree of the secondary hot water heating three-way valve 18b. Part of the hot water supplied to the refrigerating machine 20 is led to the secondary hot water heating heat exchanger 70 via the secondary hot water heating hot water bypass pipe 75, and the secondary hot water led by the secondary hot water pipe 76. The temperature of the secondary hot water is raised by exchanging heat with the hot water supply to the hot water supply on the demand side.

  At this time, the secondary hot water heating three-way valve 18b is configured so that the temperature of the cold water (the detection result of the cold water temperature sensor 25a) and the temperature of the secondary hot water (secondary water) so that the supply heat amount by the hot water to the absorption refrigerator 20 is not insufficient. Control based on both of the detection results of the hot water temperature sensor.

  When the operation mode is set to the cold stop operation, the operation of the absorption refrigerator 20 is stopped as a common operation when the hot water is stopped and the hot water is generated. While the absorption chiller 20 is stopped, the exhaust gas main damper 17a is closed and the exhaust gas bypass damper 55a is closed in order to prevent changes in the internal state such as the concentration of hydraulic fluid due to the temperature rise inside the absorption chiller 20. Is opened, the supply of exhaust gas to the absorption chiller 20 is stopped, and the supply of warm water is also stopped to protect the absorption chiller 20 main body.

  That is, when the operation mode is set to the cold stop operation and the hot water stop, the external heat radiation three-way so that the entire amount of the hot water whose temperature has risen by cooling the engine body 12 is led to the external heat radiation hot water bypass pipe 65 The opening degree of the valve 18a is controlled, and the hot water that has been led to the external heat radiating heat exchanger 60 by the external heat radiating hot water bypass pipe 65 and radiated to the cooling water is again led to the engine body 12. In addition, since there is no flow of warm water at the position of the secondary warm water heating three-way valve 18b, it does not affect the overall operation, but from the viewpoint of protecting the stopped absorption refrigerator 20 through the warm water pipe 18. When the warm water flows in, the opening degree of the secondary warm water overheating three-way valve 18b is set so that the warm water flows to the warm water bypass pipe 75 side for the secondary warm water heating.

  Further, when the operation mode is set to the cold stop operation and the generation of hot water, the secondary water is supplied so that the total amount of the hot water whose temperature has been increased by cooling the engine body 12 is led to the hot water bypass pipe 75 for secondary hot water heating. The degree of opening of the hot water heating three-way valve 18b is controlled, and the hot water heated by the secondary hot water heating heat exchanger 70 through the secondary hot water heating hot water bypass pipe 75 and heated to the engine main body 12 again. Control as you are. The temperature of the secondary hot water supplied to the demand side by the secondary hot water pipe 76 is controlled by controlling the opening of the external heat radiating three-way valve 18a based on the detection result of the secondary hot water temperature sensor 76a. By adjusting the flow rate of hot water that is guided from 18 to the external heat dissipating heat exchanger 60 through the external heat dissipating three-way valve 18a and the external heat dissipating hot water bypass piping 65, This is done by adjusting the flow rate of the warm water sent to the heat exchanger 70 for heating the secondary warm water via the warm water heating three-way valve 18b and the secondary warm water heating warm water bypass pipe 75. As a result, the supply temperature of the secondary hot water is controlled without passing hot water through the absorption refrigerator 20 that has stopped, and the cooling heat of the engine body 12 is released to maintain the cooling of the engine body 12. can do.

  The effect in this Embodiment comprised as mentioned above is demonstrated.

  Generated from a power generation unit in a combined heat and power system (cogeneration system) that seeks to operate energy efficiently by using the heat generated by the power generation unit that drives the generator with an engine, etc., and using the exhaust heat from the power generation unit In addition to the water vapor component produced by the combustion of hydrocarbons, the exhaust gas that is produced may contain corrosive components such as nitrogen oxides and sulfur oxides produced by the purity of the fuel and the state of combustion.

  Therefore, the power generation unit and the absorption chiller are combined to generate electric power in the power generation unit, and the exhaust gas of the power generation unit is discharged from the high pressure regenerator, high re-inlet heat exchanger, low re-auxiliary heat in the absorption chiller. In the case where heat is recovered to a low temperature by introducing it to an exchanger and a low re-entry heat exchanger, when the exhaust gas of the power generation unit is recovered to a low temperature with an absorption chiller, the steam component is reduced due to a decrease in the temperature of the exhaust gas. It is conceivable that corrosion occurs in equipment such as heat exchangers by condensation as it adheres to the inner surface of a pipe or the like through which the exhaust gas passes, and the corrosive component of the exhaust gas dissolves in the water droplet.

  In addition, when replacing the heat exchanger inside the absorption chiller for reasons such as corrosion, the deterioration of the entire absorption chiller is prevented due to internal corrosion caused by the reaction between oxygen in the atmosphere and the absorption liquid. In addition, it is necessary to recover the absorption liquid in the heat exchanger, and there is a problem that the replacement work becomes complicated and difficult.

  In contrast, in the present embodiment, the exhaust gas discharged from the prime mover and the hot water circulated through the prime mover to cool the prime mover are provided outside the heat-driven refrigerator that is driven using a heat source. An exhaust gas hot water heat exchanger for exchanging heat between the exhaust gas passing through the exhaust gas flow path on the downstream side via the heat driven refrigerator and the hot water passing through the hot water flow path from the prime mover to the heat driven refrigerator is disposed. Since it comprised as mentioned above, maintainability can be improved, aiming at the improvement of the collection | recovery efficiency of the exhaust heat from the motor | power_generators used for an electric power generation.

  That is, in the present embodiment, the heat of the exhaust gas is recovered by the exhaust gas heat recovery unit 22 of the absorption refrigeration machine 20 to about 150 to 200 ° C., and then the exhaust gas hot water heat exchange separated from the absorption refrigeration machine 20 is performed. Heat recovery is performed at a temperature as low as about 100 to 120 ° C. in the vessel 30. That is, when a portion having corrosion potential due to condensation of moisture in the exhaust gas component is separated from the absorption refrigerator 20, corrosion occurs in the exhaust gas hot water heat exchanger 30 that is a heat recovery unit up to a low temperature. However, the exhaust gas hot water heat exchanger 30 can be replaced or repaired without affecting the main body of the absorption chiller 20, and the system can be easily maintained and managed, and the entire system centered on the absorption chiller 20. This is very effective in preventing deterioration and maintaining performance and reliability for a long period of time.

  Further, since the exhaust gas hot water heat exchanger 30 is provided in the hot water pipe 18 from the engine power generation unit 11 to the absorption chiller 20, the heat of the exhaust gas is recovered in the hot water without impairing the cooling function of the engine body 12, and It can be effectively used as a heat source for generation.

  Further, an exhaust gas main damper 17a is provided in the exhaust gas pipe 17 from the engine power generation unit 11 to the exhaust gas heat recovery unit 22 of the absorption refrigerator 20, and the exhaust gas inlet side (upstream side) of the exhaust gas main damper 17a is exchanged with exhaust gas hot water heat. The exhaust gas bypass pipe 55 connecting the exhaust gas outlet side (downstream side) of the vessel 30 was provided, and the exhaust gas bypass damper 55 a was provided in the exhaust gas bypass pipe 55. With this configuration, the absorption refrigeration machine 20 is protected by bypassing the exhaust gas during the cold shutdown operation, and when the demand-side cold demand is smaller than the cold heat generation capacity of the cold heat generation combined heat and power supply system 10, By controlling the bypass amount and the supply amount to the absorption chiller 20, it is possible to control the heat generation capacity.

  Further, an external heat dissipating hot water bypass pipe 65 that bypasses the hot water from the inlet side (upstream side) to the outlet side (downstream side) of the absorption chiller 20 is provided in the hot water pipe 18 that circulates the hot water generated from the engine power generation unit 11. An external heat dissipating three-way valve 18a is provided at the branch to the external heat dissipating hot water bypass pipe 65, and the external heat dissipating heat exchange is performed on the external heat dissipating hot water bypass pipe 65 by the cooling water supplied from the outside. Since the cooler 60 is provided, it is possible to protect the absorption refrigeration machine 20 by bypassing the hot water during the cooling stop operation, and to release the cooling heat of the engine body 12 to the cooling water and maintain the cooling of the engine body 12. It becomes.

  Further, a hot water bypass pipe 75 for secondary hot water heating that bypasses the hot water from the inlet side (upstream side) to the outlet side (downstream side) to the absorption refrigerator 20 in the hot water flow path 18 generated from the engine power generation unit 11. The secondary hot water heating three-way valve 18b is disposed at the branch to the hot water bypass pipe 75 for secondary hot water heating, and the secondary hot water supplied to the hot water load system is placed on the hot water bypass pipe 75 for secondary hot water heating. Since the secondary hot water heating heat exchanger 70 to be heated is provided, there is no demand-side cold demand, operation when there is hot water demand, and further, simultaneous supply operation of cold water and hot water is possible.

10 Cold Heat Generation Type Combined Heat and Power System 11 Engine Power Generation Unit 12 Engine Body (Motor)
13 Generator 14 Radiator 14a Fan 15 Fuel supply path 16 Power transmission path 17 Exhaust gas pipe 17a Exhaust gas main damper 18 Hot water pipe 18a External heat dissipation three-way valve 18b Secondary hot water heating three-way valve 18c, 18d Hot water temperature sensor 19 Outside air 20 Absorption type Refrigerator (thermally driven refrigerator)
21 Cold water pump 22 Exhaust gas heat recovery part 22a Heat transfer structure 23 Hot water heat recovery part 23a, 24a, 28a Heat transfer pipe 24 Low temperature regenerator 25 Cold water pipe 25a Cold water temperature sensor 26 Evaporator 26a Refrigerant pumps 24b, 26b, 27b Spreading pipe 27 Absorption 27a Solution pump 28 Condenser 29a Low temperature solution heat exchanger 29b High temperature solution heat exchanger 31 Hot water pump 35 Controller 35a Operation control unit 36 Operation setting unit 55 Exhaust gas bypass pipe 55a Exhaust gas bypass damper 60 External heat dissipation heat exchanger 65 External Heat-dissipating hot water bypass pipe 70 Secondary hot water heat exchanger 71 Secondary hot water pump 75 Secondary hot water bypass pipe 76 Secondary hot water pipe 76a Secondary hot water temperature sensor 90 Cooling tower 90a, 90b On-off valve 91 Cooling water pump 95 , 96 Cooling water piping 100 Engine power generation unit 200 Cold / hot water supply unit Cold supply system)

Claims (8)

A generator driven by a prime mover;
A heat-driven refrigerator that is driven by using exhaust gas discharged from the prime mover and hot water circulated through the prime mover to cool the prime mover; and
Exhaust gas that is disposed outside the heat-driven refrigerator, passes through the exhaust gas flow path on the downstream side through the heat-driven refrigerator, and hot water passes through the hot water flow path from the prime mover to the heat-driven refrigerator. A combined heat and power system comprising an exhaust gas hot water heat exchanger for exchanging heat between the two. In the cogeneration system according to claim 1,
An exhaust gas hot water heat exchanger is provided in the hot water flow path in the vicinity of the prime mover. In the cogeneration system according to claim 1,
An exhaust gas main damper provided in an exhaust gas flow path between the prime mover and the heat-driven refrigerator, and adjusting a flow rate of the exhaust gas sent to the heat-driven refrigerator;
An exhaust gas bypass channel for guiding the exhaust gas from an exhaust gas channel between the prime mover and the exhaust gas main damper to an exhaust gas channel downstream of the exhaust gas hot water heat exchanger;
An exhaust gas bypass damper that is provided in the exhaust gas bypass channel and adjusts the flow rate of the exhaust gas passing through the exhaust gas bypass channel;
Starting the heat-driven refrigerator, opening the exhaust gas main damper to guide the exhaust gas from the prime mover to the heat-driven refrigerator, and closing the exhaust gas bypass damper and passing through the exhaust gas bypass channel A heat generating operation for shutting off the heat, stopping the heat-driven refrigerator, closing the exhaust gas main damper to shut off the exhaust gas led from the prime mover to the heat-driven refrigerator, and disposing the exhaust gas bypass damper A combined heat and power supply comprising: a controller that opens and switches a cooling stop operation that leads the exhaust gas from the prime mover to the exhaust gas flow path downstream of the exhaust gas hot water heat exchanger via the exhaust gas bypass flow path system. In the cogeneration system according to claim 1,
An exhaust gas main damper provided in an exhaust gas flow path between the prime mover and the heat-driven refrigerator, and adjusting a flow rate of the exhaust gas sent to the heat-driven refrigerator;
An exhaust gas bypass channel for guiding the exhaust gas from an exhaust gas channel between the prime mover and the exhaust gas main damper to an exhaust gas channel downstream of the exhaust gas hot water heat exchanger;
An exhaust gas bypass damper that is provided in the exhaust gas bypass channel and adjusts the flow rate of the exhaust gas passing through the exhaust gas bypass channel;
A cold water thermometer for measuring the temperature of the cold water cooled by the heat-driven refrigerator and supplied to the demand side;
The flow rate of the exhaust gas led from the prime mover to the thermally driven refrigerator by starting the thermally driven refrigerator and adjusting the opening of the exhaust gas main damper based on the measurement result of the cold water thermometer And adjusting the opening of the exhaust gas bypass damper based on the measurement result of the cold water thermometer to adjust the flow rate of the exhaust gas passing through the exhaust gas bypass passage, and the heat driven type The refrigerator is stopped, the exhaust gas main damper is closed to shut off the exhaust gas introduced from the prime mover to the heat-driven refrigerator, and the exhaust gas bypass damper is opened to allow the exhaust gas from the prime mover to flow through the exhaust gas bypass flow. A combined heat and power supply comprising a control unit that switches between a cooling stop operation that leads to an exhaust gas flow path downstream of the exhaust gas hot water heat exchanger via a channel Stem. In the cogeneration system according to claim 1,
The heat drive from the hot water flow path upstream of the heat drive refrigerating machine and downstream of the exhaust gas hot water heat exchanger in the hot water flow path for circulating the hot water between the prime mover and the heat driven refrigerating machine An external heat dissipating hot water bypass passage for guiding the hot water to a hot water passage on the downstream side of the refrigerator,
The flow rate ratio of the hot water between the hot water flow channel and the external heat radiating hot water bypass flow channel is provided at a branch portion between the hot water flow channel upstream of the heat-driven refrigerator and the external heat radiating hot water bypass flow channel. A three-way valve for external heat dissipation to be adjusted;
A combined heat and power system, comprising: an external heat dissipation heat exchanger that is provided in the external heat dissipation hot water bypass flow path and cools the hot water using cooling water supplied from outside the combined heat and power system. In the cogeneration system according to claim 1,
The heat drive from the hot water flow path upstream of the heat drive refrigerating machine and downstream of the exhaust gas hot water heat exchanger in the hot water flow path for circulating the hot water between the prime mover and the heat driven refrigerating machine A hot water bypass channel for secondary hot water heating that guides the hot water to the hot water channel downstream of the mold refrigerator,
The hot water in the hot water flow path and the hot water bypass flow path for heating the secondary hot water is provided at a branch portion between the hot water flow path upstream of the heat-driven refrigerator and the hot water bypass flow path for heating the secondary hot water. A three-way valve for secondary hot water heating that adjusts the flow rate ratio of
A combined heat and power system comprising: a secondary hot water heating heat exchanger that is provided in the hot water bypass flow path for heating the secondary hot water and that heats the secondary hot water supplied to the hot water load system on the demand side. A heat-driven refrigerating machine driven by using exhaust gas discharged from a prime mover driving a generator and hot water circulated for cooling the prime mover as a heat source;
Cooling heat, comprising an exhaust gas hot water heat exchanger for exchanging heat between the exhaust gas after passing through the heat driven refrigerator and the hot water supplied from the prime mover to the heat driven refrigerator Supply system. A generator driven by a prime mover, an exhaust gas discharged from the prime mover, and a heat driven refrigerator driven by using hot water circulated through the prime mover to cool the prime mover, and the heat An exhaust gas hot water heat exchanger that exchanges heat between exhaust gas passing through a downstream exhaust gas flow path via a driven refrigerator and hot water passing through a hot water flow path from the prime mover to the thermally driven refrigerator. In the control method of the combined heat and power system,
The flow rate of the exhaust gas that is provided in the exhaust gas flow path between the prime mover and the heat-driven refrigerator and is sent to the heat-driven refrigerator during the execution of the cold heat generation operation in which cold heat is supplied by the heat-driven refrigerator The exhaust gas main damper is adjusted to guide the exhaust gas from the prime mover to the heat-driven refrigerator, and from the exhaust gas flow path between the prime mover and the exhaust gas main damper to the downstream side of the exhaust gas hot water heat exchanger A procedure for closing the exhaust gas bypass damper for adjusting the flow rate of the exhaust gas passing through the exhaust gas bypass channel and shutting off the exhaust gas passing through the exhaust gas bypass channel;
When performing the cooling stop operation to stop the heat-driven refrigerator, the exhaust gas main damper is closed to cut off the exhaust gas led from the prime mover to the heat-driven refrigerator, and the exhaust gas bypass damper is opened to A control method for a combined heat and power system, comprising: a step of guiding exhaust gas from a prime mover to an exhaust gas passage downstream of the exhaust gas hot water heat exchanger through the exhaust gas bypass passage.

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