Heat circulation type heating system

Abstract

To provide a heat circulation type heating system capable of suppressing a power supply capacity even from a state where there is no heat source and significantly reducing facility costs in starting the heat circulation type heating system.SOLUTION: After a raw material W is heated through a heat treatment apparatus 1, only gas is recovered to a cooler 2 and the heat of the gas is recovered by hot raw water in the cooler 2 and the gas is condensed and discharged as a distillate R. Heat from the cooler 2 is recovered, and heat raw water S heat-exchanged by the heat exchanger 3 is sent to a heat pump type steam generator 6 operated by recovering heat from the heat raw water S by a pump 5. The hot water U after giving heat to the refrigerant in the heat pump type steam generator 6 is returned to the cooler 2 and circulated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a heat circulation type heating system using a heat pump, which is capable of starting up multiple heat pumps while suppressing peak power consumption by controlling the start-up heat source and the heat circulation of multiple heat pumps when starting up the multiple heat pumps. [Background technology]

[0002] A heat pump uses an evaporator to function as a waste heat recovery device, recovering heat from the hot water heat source into a refrigerant, and then using the recovered heat to heat the water to be heated in a cooler to generate steam.This has the advantage of reducing running costs and CO2 emissions compared to combustion-based steam generation devices that generate steam using boiler equipment, etc.

[0003] Patent Document 1 describes a distillation apparatus that can be stably operated using a heat pump alone without using a heat source such as a heater.

[0004] Furthermore, Patent Document 2 discloses a system configuration that uses a heat pump to produce distilled liquid, and describes the use of a heater to heat and evaporate when the heat pump is started. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Japanese Patent Publication No. 2022-29265 [Patent Document 2] Special Publication No. 6-7881 Summary of the Invention [Problem to be solved by the invention]

[0006] However, if a startup heater that matches the output capacity is used to start a steam generation heat pump that uses heat circulation without using steam and that utilizes conventional boiler equipment, a large-capacity startup heater is required, which increases the peak power consumption at startup.

[0007] The present invention has been made in view of the above, and has an object to provide a heat circulation type heating system that can reduce the power supply capacity and also significantly reduce the equipment costs. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems and achieve the object, the heat circulation type heating system of the present invention comprises a heat treatment device that treats raw materials with steam or hot water, a cooler that recovers gas extracted from the heat treatment device, a heat exchanger that recovers heat from the cooler, a pump that sends heat source water from the heat exchanger to a heat pump type steam generator, and a plurality of heat pump type steam generators that operate by recovering the heat source water from the heat exchanger, and in which the hot water returns to the cooler after giving heat to the refrigerant in the plurality of heat pump type steam generators, a start-up heat source unit is provided between the heat exchanger and the pump, and when the plurality of heat pump type steam generators are started up, the start-up heat source unit is used to start up a first heat pump type steam generator, and the heat output output from the started first heat pump type steam generator is recovered and used as a heat source to start up the heat pump type steam generators other than the first heat pump type steam generator.

[0009] In addition, in the heat circulation type heating system according to the present invention, the startup heat source unit is a heater and a heat source tank.

[0010] Furthermore, in the heat circulation type heating system according to the present invention, in the above invention, the plurality of heat pump type steam generators are arranged in parallel with their inlets and outlets commonly connected.

[0011] Furthermore, the heat circulation type heating system of the present invention comprises a heat treatment device that treats raw materials with steam or hot water, a cooler that recovers gas extracted from the heat treatment device, a heat exchanger that recovers heat from the cooler, a pump that sends heat source water from the heat exchanger to a heat pump type steam generation device, and a plurality of heat pump type steam generation devices that operate by recovering the heat source water from the heat exchanger, and the hot water that has given heat to the refrigerant in the plurality of heat pump type steam generation devices returns to the cooler, and is characterized in that the heat circulation type heating system further comprises a heat storage unit between the heat exchanger and the pump, and the heat storage unit comprises a second heat exchanger for exchanging heat between a heat storage material, the heat source water, and the heat storage material, and the heat storage material stores excess heat during steady-state operation, and at start-up, the stored heat is used as a heat source to start up the plurality of heat pump type steam generation devices.

[0012] Furthermore, the heat circulation type heating system of the present invention is characterized in that, in the above invention, the heat storage unit comprises a low-temperature heat storage tank and a high-temperature heat storage tank, the low-temperature heat storage tank and the high-temperature heat storage tank are connected to the second heat exchanger via a reversible pump, the inlet temperature of the heat source water flowing into the second heat exchanger is obtained, and a temperature at which the excess heat of the heat source water becomes zero is set as a reference temperature, and during the steady-state operation, when the inlet temperature is higher than the reference temperature, the heat storage material is transferred from the low-temperature heat storage tank to the second heat exchanger to recover heat and then stored in the high-temperature heat storage tank, and when the multiple heat pump type steam generation devices are started up, the inlet temperature is lower than the reference temperature, and the heat storage material is transferred from the high-temperature heat storage tank to the second heat exchanger to heat the heat source water and then stored in the low-temperature heat storage tank.

[0013] Furthermore, the heat circulation type heating system of the present invention is characterized in that, in the above invention, the heat storage material is capable of starting one to multiple heat pump steam generation devices based on the heat storage capacity of the surplus heat amount.

[0014] Furthermore, the heat circulation type heating system of the present invention is characterized in that, in the above invention, it further comprises the startup heat source unit between the heat storage unit and the pump, and when the heat storage capacity of the heat storage material is insufficient, the heater of the startup heat source unit is used to start one of the heat pump type steam generating devices, and the steam output from the started first heat pump type steam generating device is used to start the heat pump type steam generating devices other than the first heat pump type steam generating device, and when the heat storage capacity of the heat storage material is sufficient, the heat of the heat storage material in the heat storage unit is used to start the multiple heat pump type steam generating devices.

[0015] Furthermore, in the heat circulation type heating system according to the present invention, the heating treatment device is a distillation apparatus equipped with a distillation column and a reboiler. [Effects of the Invention]

[0016] According to the present invention, a heat circulation type heating system can be started without a heat source, and by controlling the heat circulation of the startup heater and multiple heat pumps, startup operation can be performed with a small-capacity startup heater while reducing peak power consumption. [Brief explanation of the drawings]

[0017] [Figure 1] FIG. 1 is a circuit diagram showing the overall configuration of a heat circulation type heating system according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a diagram showing an example of an operating state in which the power required at startup of the heat circulation type heating system according to the first embodiment of the present invention is minimized. [Figure 3] FIG. 3 is a diagram showing an example of an operating state in which the power consumption at the start of a conventional heat circulation type heating system using only a heater is minimized. [Figure 4] FIG. 4 is a circuit diagram showing the overall configuration of a heat circulation type heating system according to a second embodiment of the present invention. [Figure 5] FIG. 5 is a circuit diagram showing the overall configuration of a heat circulation type heating system according to a third embodiment of the present invention. [Figure 6]FIG. 6 is a diagram showing an example of a heat treatment device. DETAILED DESCRIPTION OF THE INVENTION

[0018] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

[0019] First, the overall configuration of a heat circulation type heating system 100 according to a first embodiment of the present invention will be described.

[0020] FIG. 1 is a diagram showing the overall configuration of a heat circulation heating system 100 according to a first embodiment of the present invention. The heat circulation heating system 100 comprises a heat treatment device 1, a cooler 2, a heat exchanger 3, a startup heat source 4, a pump 5, multiple heat pump steam generators 6, a heat exchanger 31, and a bypass piping LB1. After raw material W is heated in the heat treatment device 1, only the gas is recovered to the cooler 2. The gas loses heat to the heat source water in the cooler 2, condenses, and is discharged as distillate R. Heat is recovered from the cooler 2, and the heat source water S is heat-exchanged in the heat exchanger 3. The heat source water S is then sent to the heat pump steam generator 6, which operates by recovering heat from the heat source water S, by the pump 5. The system is based on the premise that after heat is given to the refrigerant in the heat pump steam generator 6, the hot water U is returned to the cooler 2 and circulated. The heat circulation heating system 100 according to the first embodiment of the present invention has four pumps 5 (5a to 5d) and four heat pump steam generators 6 (6a to 6d), which are connected in parallel with their inlets and outlets commonly connected. Note that, although the first embodiment of the present invention has been described as having four heat pump steam generators 6, two or more may be used. The heat exchanger 31 is a heat exchanger for releasing excess thermal energy to the outside to achieve a heat balance.

[0021] <Example of steady-state operation> As shown in FIG. 1, in the first embodiment of the present invention, raw material W (25°C) is heated by heat treatment device 1, and the extracted gas (70°C to 100°C) has heat recovered to heat source water S in cooler 2 and is discharged as distillate R (75°C). The heat source water S (50°C to 80°C) that has recovered heat from cooler 2 and undergoes heat exchange in heat exchanger 3 is sent to four heat pump steam generators 6a to 6d by four pumps 5a to 5d via heat source tank 9. The four heat pump steam generators 6a to 6d then give heat to the refrigerant, generating hot water U (40°C to 70°C), which returns to cooler 2 in a circulating manner. The distillate R, heat source water S, and hot water U vary depending on the heat treatment temperature of the heat treatment target, the heating capacity of heat treatment device 1, and the cooling capacity of cooler 2.

[0022] In the heat circulation heating system 100, steam output from the four heat pump steam generators 6a to 6d join together to supply steam H at 105 to 150°C to the heat treatment device 1. Condensed water C (80 to 95°C) that has undergone heat exchange in the heat treatment device 1 is configured as a circulation type that returns to the water supply of the four heat pump steam generators 6a to 6d via a tank 7 (a circulation that provides heat). The first embodiment of the present invention is a closed circulation circuit and can be implemented without providing an external water supply, but it is possible to supply water to the tank 7 in advance and store it there in case water supply is required.

[0023] <Example of startup operation> However, when the heat treatment line of the heat circulation heating system 100 is started and operation is stabilized, gas is not discharged from the heat treatment unit 1, and heat recovery by the cooler 2 is not possible. Therefore, the heat source water S for starting the heat pump steam generator 6 cannot be heated. Therefore, in the first embodiment of the present invention, a heater 8 and a heat source tank 9 are provided in the startup heat source unit 4 between the heat exchanger 3 and the pump 5, and the circulating water is heated by the heater 8 to start operation of the heat pump steam generator 6a. The steam H (105°C to 120°C) output from the heat pump steam generator 6a is supplied to the heat treatment unit 1. However, since no raw material W is supplied to the heat treatment unit 1 at the start of operation, the steam passes through the heat treatment unit 1 as steam and flows out into the startup operation bypass pipe LB1. The steam H that passes through the bypass pipe LB1 flows into the heat exchanger 3, where heat is recovered by the circulating water, becoming condensed water C (80°C to 95°C), which returns to the heat pump steam generator 6a via the tank 7. The circulating water from which heat has been recovered in the heat exchanger 3 serves as heat source water S, via a heat source tank 9, as a heat source for activating the heat pump steam generators 6b to 6d other than the heat pump steam generator 6a.

[0024] 1 and 2 show an example of an operating state in which the power required to start the heat pump steam generator 6 according to the first embodiment of the present invention is minimized. First, in step 1, when the heat pump steam generator 6a is started at 60 kW output using a heater 8 with a heater power of 40 kW as a heat source, the power of the heat pump steam generator 6a is 20 kW, and the elapsed time until start-up is 30 minutes. The power consumption in step 1 is 30 kWh. Next, in step 2, when the heat pump steam generators 6b to 6d are started at 30 kW output using the output of the heat pump steam generator 6a as a heat source, the heater power is 40 kW, the power of the heat pump steam generators 6 is 50 kW, and the elapsed time until start-up is 20 minutes. The power consumption in step 2 is 30 kWh. In step 3, the output of the heat pump steam generators 6b to 6d is increased to 60 kWh using the self-exhausted heat of the heat pump steam generator 6 as a heat source, so that the output required for the heating processor is 240 kWh. The power of the heat pump steam generator 6 in step 3 is 80 kW, and the elapsed time of the output increase is 10 minutes. The amount of power in step 3 is 13.3 kWh. The peak power during the operating state where the power is minimum according to the first embodiment of the present invention is 90 kWh, which is the sum of the heater power and the power of the heat pump steam generator.

[0025] Fig. 3 shows the operating state when four conventional heat pump steam generators 6 and heaters 8 are started up simultaneously using them as heat sources (step 1'). To start up the four heat pump steam generators 6a to 6d with an output of 60 kWh each, the heater power required is 160 kWh, and the power of the heat pump steam generator 6 is 80 kWh. The peak power is then 240 kWh, which is the sum of the heater power and the power of the heat pump steam generators. In the first embodiment of the present invention, by controlling the heat circulation of the four heat pump steam generators 6a to 6d using a heater 8, the heater power is reduced to one-fourth of that required in conventional operation in which the four heat pump steam generators 6a to 6d are started using only the heater 8, and the peak power is reduced from 240 kWh to 90 kWh, thereby making it possible to reduce equipment costs and running costs.

[0026] <Second embodiment> Next, a heat circulation type heating system 101 according to a second embodiment of the present invention will be described. In the heat circulation type heating system 101 and the heat circulation type heating systems 102 and 103 described below, the same components as those in the heat circulation type heating system 100 are designated by the same reference numerals, and detailed descriptions thereof will be omitted.

[0027] 4 is a circuit diagram showing the overall configuration of a heat circulation type heating system 101. Compared to the heat circulation type heating system 100, the heat circulation type heating system 101 includes a heat storage unit 10. The heat storage unit 10 replaces the heater 8, and includes a temperature sensor 11 provided at the inlet of the second heat exchanger 12, a reversible pump 13 that operates based on the temperature measured by the temperature sensor 11, a low-temperature heat storage tank 14 to which the heat storage material M is transferred by the reversible pump 13, and a high-temperature heat storage tank 15.

[0028] As shown in FIG. 4 , in the second embodiment of the present invention, the heat storage unit 10 is configured such that a heat exchanger 12 is disposed between the outlet of the heat exchanger 3 and the heat pump steam generator 6 to exchange heat between the recovered heat source water S and a low-temperature heat storage tank 14 and a high-temperature heat storage tank 15. The heat storage tank side of the heat exchanger 12 is connected to the low-temperature heat storage tank 14 and the high-temperature heat storage tank 15 via a reversible pump 13. The inlet temperature at which the heat source water S flows into the heat exchanger 12 is acquired using a temperature sensor 11. The temperature at which the excess heat of the heat source water S becomes zero is set as a reference temperature. During steady-state operation, when the temperature acquired by the temperature sensor 11 is higher than the reference temperature, the reversible pump 13 transfers the heat storage material M from the low-temperature heat storage tank 14 to the heat exchanger 12, where the heat is recovered and then stored in the high-temperature heat storage tank 15. The heat source water S that has passed through the heat exchanger 12 is sent via a heat source tank 9 as a heat source for operating the heat pump steam generator 6. Other steady-state operations are the same as those in the first embodiment of the present invention, and therefore detailed explanations will be omitted.

[0029] On the other hand, during start-up operation in the second embodiment of the present invention, when the temperature acquired by the temperature sensor 11 is lower than the reference temperature, the heat storage material M is transferred by the reversible pump 13 from the high-temperature heat storage tank 15 to the low-temperature heat storage tank 14 via the heat exchanger 12. After the heat storage material M is recovered in the heat exchanger 12 and the heat source water S is heated, it is stored in the low-temperature heat storage tank 14. The heated heat source water S becomes a heat source that starts the heat pump steam generator 6.

[0030] During startup operation of the second embodiment of the present invention, as described above, excess heat generated during steady-state operation is stored in the high-temperature heat storage tank 15, and at the next startup, the heat source water S is heated by heat dissipation from the heat storage material M from the high-temperature heat storage tank 15 to the low-temperature heat storage tank 14, and by controlling the heat circulation of the four heat pump steam generators 6a to 6d, the heater power required for startup to heat the heat source water S is no longer required, making it possible to reduce the power supply capacity and achieve a completely steam boilerless system.

[0031] Furthermore, if there is sufficient heat storage capacity, it becomes possible to start up a plurality of heat pump steam generating devices simultaneously, which makes it possible to significantly reduce the start-up time. <Third embodiment> 5 is a circuit diagram showing the configuration of a heat circulation type heating system 102 according to a third embodiment of the present invention. The heat circulation type heating system 102 includes both a thermal storage unit 10 and a heater 8.

[0032] As shown in Figure 5, when the heat circulation type heating system 102 is started for the first time or when it is started after a certain number of days have passed since the previous start-up and the heat storage capacity on the heat storage tank side is insufficient, it starts up in the same way as the heat circulation type heating system 101 using the heater 8, stores excess heat in the high-temperature heat storage tank 15 during steady-state operation, and from the next start-up onwards, operates in the same way as the heat circulation type heating system 102, thereby making it possible to reduce the power supply capacity. <Heat treatment device> As shown in FIG. 6, in the heat circulation type heating system 103, the heat treatment device 1 is a distillation apparatus having a reboiler 21 and a distillation column 22.

[0033] In the heat circulation type heating system 103 shown in Figure 6, the steam H output from the four heat pump steam generators 6a to 6d is joined together and sent to the reboiler 21 of the distillation apparatus, where heat is given to the raw material W, which becomes condensed water C and is returned to the four heat pump steam generators 6a to 6d as feed water. The raw material W circulating through the reboiler 21 and distillation column 22 is heated and vaporized in the reboiler 21, and returns to the distillation column 22 in a two-phase gas-liquid state where it is separated into gas and liquid. The liquid is returned to the reboiler 21 and heated, and only the distilled gas is sent to the cooler 2 (for example, a condenser).

[0034] The gas recovers heat and is condensed into hot water U in cooler 2, which is then discharged as distillate R via tank 23. The hot water U from which the heat has been recovered is sent as heat source water S to the four heat pump steam generators 6a to 6d, where it operates as a heat source for the four heat pump steam generators 6a to 6d. After that, the hot water U gives heat to the refrigerant in the four heat pump steam generators 6a to 6d, and returns to cooler 2 as hot water U. In addition, the liquid containing a large amount of low-boiling-point substances that flows out from the bottom of the distillation apparatus is discharged to the outside as bottoms V.

[0035] In the present invention, the distillation apparatus is described as performing steam heating on an alcohol such as ethanol as the object to be heated, but the invention is not limited to this and may also be applied to products that require heating and cooling, such as pharmaceuticals, food, and sterilization.

[0036] Furthermore, the above-described embodiment of the present invention is merely an example, and it is clear that any appropriate modifications, alterations, additions, etc. made within the spirit of the present invention in respects other than those described above will also fall within the scope of the claims of the present application. [Explanation of symbols]

[0037] 1 Heat treatment device 2 cooler 3,31 Heat exchanger 4 Heat source for startup 5, 5a~5d Pump 6, 6a to 6d Heat pump steam generator 7,23 Tank 8 Heater 9 Heat source tank 10 Heat storage section 11 Temperature Sensor 12 Second heat exchanger 13 Reversible pump 14 Low temperature heat storage tank 15 High temperature heat storage tank 21 Reboiler 22 Distillation tower 100~103 Heat circulation type heating system LB1 Start-up bypass piping LB2 Bypass piping for normal operation C Condensed water H vapor M Heat storage material R distillate S Thermal raw water U Hot water V Bottoms W raw material

Claims

1. a heat treatment device for treating the raw material with steam or hot water; a cooler that recovers the gas extracted from the heat treatment device; a heat exchanger that recovers heat from the cooler; a pump for sending the heat source water from the heat exchanger to the heat pump steam generator; a plurality of heat pump steam generating devices that operate by recovering heat raw water from the heat exchanger; In a heat circulation type heating system in which the hot water returns to the cooler after heat is given to the refrigerant by the plurality of heat pump type steam generating devices, a startup heat source unit is provided between the heat exchanger and the pump; When the plurality of heat pump steam generating devices are started up, starting up a first heat pump steam generating device using the startup heat source; The heat output output from the activated first heat pump steam generating device is recovered and used as a heat source, A heat circulation type heating system, characterized in that the heat pump type steam generating device other than the first heat pump type steam generating device is started.

2. 2. The heat circulation type heating system according to claim 1, wherein the startup heat source unit is a heater and a heat source tank.

3. The heat circulation type heating system according to claim 1, wherein the plurality of heat pump type steam generating devices are arranged in parallel with their inlets and outlets commonly connected.

4. a heat treatment device for treating the raw material with steam or hot water; a cooler that recovers the gas extracted from the heat treatment device; a heat exchanger that recovers heat from the cooler; a pump for sending the heat source water from the heat exchanger to the heat pump steam generator; a plurality of heat pump steam generating devices that recover the heat raw water from the heat exchanger and operate; In a heat circulation type heating system, the hot water after heat is given to the refrigerant by the plurality of heat pump type steam generating devices is returned to the cooler, a heat storage unit is provided between the heat exchanger and the pump; the heat storage unit includes a heat storage material and a second heat exchanger for exchanging heat between the heat source water and the heat storage material, The heat storage material stores excess heat during steady-state operation, and at startup, the stored heat serves as a heat source to start up the multiple heat pump steam generators.

5. the heat storage unit includes a low-temperature heat storage tank and a high-temperature heat storage tank, the low-temperature heat storage tank and the high-temperature heat storage tank are connected to the second heat exchanger via a reversible pump; acquiring an inlet temperature of the heat source water flowing into the second heat exchanger; The temperature at which the excess heat of the heat source water becomes zero is set as the reference temperature, During the steady operation, when the inlet temperature is higher than the reference temperature, the heat storage material is transferred from the low-temperature heat storage tank to the second heat exchanger to recover heat, and then stored in the high-temperature heat storage tank; When the plurality of heat pump steam generating devices are started up, The inlet temperature becomes lower than the reference temperature, 5. The heat circulation type heating system according to claim 4, wherein the heat storage material is transferred from the high-temperature heat storage tank to the second heat exchanger, where the heat source water is heated, and then stored in the low-temperature heat storage tank.

6. The heat circulation type heating system according to claim 5, wherein the heat storage material is capable of activating one to a plurality of the heat pump type steam generating devices based on the heat storage capacity of the surplus heat amount.

7. The heater is provided in the startup heat source section between the heat storage section and the pump, When the heat storage capacity of the heat storage material is insufficient, the first heat pump steam generator is started using the heater of the start-up heat source unit, and the heat pump steam generators other than the first heat pump steam generator are started using the steam output from the started first heat pump steam generator, The heat circulation type heating system according to claim 5, characterized in that when the heat storage capacity of the heat storage material is sufficient, the heat of the heat storage material in the heat storage section is used to start the first heat pump type steam generating device or the plurality of heat pump type steam generating devices.

8. 8. The heat circulation type heating system according to claim 1, wherein the heating treatment device is a distillation apparatus equipped with a distillation column and a reboiler.

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