JP2006000327A - Processing equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a treatment device capable of effectively heating an object of heating whose temperature should be lowered after the heating by heating a fluid to be sterilized by a heat pump device and further cooling the fluid. <P>SOLUTION: A heat-pump type sterilization device 1 is structured to heat and sterilize the object of sterilization flowing in a channel 1A by a heat pump 1B with a refrigerating cycle consisting of a compressor 11, a heat exchanger 31 for heating, an expansion valve 13 as a depression device, and a heat exchanger 33 for cooling, etc. The object of sterilization is heated/sterilized and cooled in the channel 1A, and after that, the object of sterilization is fed to a medium of using the object. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a processing apparatus that heats a fluid containing various bacteria, molds, and the like using a heat pump apparatus including a refrigeration cycle including a compressor, a heat radiating unit, a pressure reducing device, a heat absorbing unit, and the like.

  Conventionally, as a sterilizer for sterilizing fluids such as milk, water and air containing various pathogenic bacteria and molds used in hydroponic cultivation, food processing industry, aquaculture industry, hospitals, etc., compressors, heat dissipation parts In addition, a sterilizer using a heat pump device including a refrigeration cycle configured by sequentially connecting a decompression device, a heat absorption unit, and the like has been proposed. This heat pump type sterilizer is filled with a refrigerant in the heat pump, and heat sterilizes the fluid to be sterilized using heat when the refrigerant gas compressed to high temperature and high pressure by the compressor dissipates heat in the heat radiating unit. It was a thing.

Moreover, the fluid as the sterilization target after being sterilized by heating has been cooled to the temperature before heating by utilizing the endothermic action of the endothermic portion. Thus, the high-temperature fluid sterilized by heat is effectively cooled by the refrigerant of the heat absorption part and can be used after being lowered to a predetermined temperature (see, for example, Patent Document 1).
Japanese Patent No. 2760377

  However, in the conventional heat pump sterilizer, when the sterilization process is completed and the sterilizer is stopped, the flow path in which the fluid to be sterilized flows in the sterilizer is at room temperature, and particularly when the outdoor temperature is high, such as in summer In some cases, a small amount of bacteria remain in the fluid remaining in various places in the flow path, for example, the intermediate temperature section or the cooling section, and a large amount of bacteria grow in the flow path. is there.

  At the time of the next operation, particularly in the initial stage of the operation, there is a possibility that a fluid containing a large amount of bacteria as described above is sent out from the sterilizer.

  Therefore, the present invention has been made to solve the related art technical problem, and before starting the heat sterilization apparatus, a heat treatment apparatus provided with means for heat sterilizing the inside of the flow path in the apparatus, and A sterilizer is provided.

  The processing apparatus of the present invention includes a flow path through which a fluid to be heated circulates, a heating unit that heats the fluid in the flow path, and a utilization unit that uses the fluid heated by the heating unit, After heating the fluid by the heating means, a first heating mode in which a process of supplying the heated fluid to the means is performed across a predetermined pause period, and in the pause period, In the heat treatment apparatus, the second heating mode is performed in which the fluid is heated while the supply to the utilization unit is stopped. The second heating mode is performed in the first half of the pause period. It is characterized by that.

  In addition to the invention according to claim 1, the processing apparatus according to claim 2 further includes a cooling unit that cools the fluid heated by the heating unit before supplying the fluid to the utilization unit. The second heating mode is performed in a state where cooling of the fluid is stopped.

  The processing apparatus according to claim 3 is a refrigeration circuit including a compressor, a heat radiating unit, a heat absorbing unit, and an expansion unit, and a heating target connected to the heat radiating unit using heat radiated from the refrigeration circuit. A heating target flow path including heating means for heating the heating target, and cooling means for cooling the heating target connected to the heat absorbing section and heated by the heating means using heat absorption of the refrigeration circuit, After heating the object to be heated by the heating means, a normal heating operation in which a process for transporting the object to be heated to the cooling means for cooling is performed across a predetermined pause period, and the heat absorption in the pause period And a flow path heating operation for heating the heating target in a state where heat absorption by the unit is reduced or stopped.

  In addition to the invention according to claim 3, the processing apparatus according to claim 4 is characterized in that the flow path heating operation is performed in the first half of the pause period.

  In addition to the invention according to claim 3, the processing device according to claim 5 is a temperature sensor that measures the temperature of the heating object between the heating unit and the cooling unit, and an external device that measures the outside air temperature. An air temperature sensor, and the flow path heating operation is executed before the temperature of the heating object measured by the temperature sensor in the pause period is lowered to the outside air temperature measured by the outside air temperature sensor. It is characterized by.

  The processing apparatus according to claim 6 is a refrigeration circuit including a compressor, a heat radiating unit, a heat absorbing unit, and expansion means, and a heating target connected to the heat radiating unit using heat radiated from the refrigeration circuit. A heating target flow path that includes a heating means that heats the heating target that is connected to the heat absorbing portion and that cools the heating target that is heated by the heating means using the heat absorption of the refrigeration circuit, an outside air temperature sensor, A heat treatment apparatus for performing a normal heating operation in which the heating object is heated by the heating means, and then the heating object is transported to the cooling means and cooled for a predetermined pause period In the above, the outside air temperature is measured by the outside air temperature sensor during the pause period, and when the outside air temperature is equal to or higher than a predetermined value, the heating target is heated in a state where the heat absorption by the heat absorbing unit is reduced or stopped After running, The first operation mode for executing the normal heating operation is executed, and when the outside air temperature is less than a predetermined value, the second operation mode for executing the normal heating operation without performing the flow path heating operation is performed. It is characterized by performing.

  The processing apparatus according to claim 7 is characterized in that, in addition to the invention according to claim 6, the measurement of the outside air temperature by the outside air temperature sensor is performed in the latter half of the suspension period.

  In addition to the inventions described in claims 2 to 7, the processing apparatus described in claim 8 includes a storage unit that can store the heating target between the heating unit and the cooling unit. It is characterized by that.

  The processing apparatus according to claim 9 is a heating object using a refrigeration circuit including a compressor, a heat radiating portion, a heat absorbing portion, and an expansion means, and using heat radiated from the refrigeration circuit connected to the heat radiating portion. A heating target flow path that includes: a heating unit that heats the heating target, and a cooling unit that cools the heating target that is heated by the heating unit by using the heat absorption of the refrigeration circuit. A storage section that can store the heating target disposed between the cooling means and the cooling target after being heated by the heating means and stored in the storage section. It is conveyed to the means and cooled.

  The processing apparatus according to claim 10 is characterized in that, in addition to the inventions according to claims 1 to 9, the heating object includes bacteria, and the bacteria are sterilized by the heating means.

  According to the present invention, the fluid can be heated by the heat pump device and further cooled, so that it is necessary to lower the temperature particularly after heating, for example, nutrient solution, juice, milk, etc. used in hydroponics system A processing apparatus capable of effectively performing a heat treatment of a beverage is provided.

  Next, preferred embodiments of the present invention will be described in detail with reference to the drawings. In addition, the heat pump type sterilization apparatus using the heat pump type heat treatment apparatus in this embodiment performs heat sterilization of nutrient solution used in hydroponic cultivation systems used for hydroponic cultivation such as strawberries and tomatoes as sterilization targets. It is.

  Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1: has shown schematic structure figure of the heat pump type sterilizer 1 as one Example of this invention.

  The heat pump type sterilizer 1 of FIG. 1 determines and controls the flow path portion 1A as a nutrient solution flow path, the heat pump 1B that is a heat pump apparatus equipped with a refrigeration cycle, and the sterilization mode when the flow path is sterilized. And a control unit 80 as a means for performing the above.

  1 in FIG. 1 is a nutrient solution usage side. A nutrient solution tank 2A, a nutrient solution tank 2B, a nutrient solution adjustment tank 2C, fertilizer component addition devices 2D, 2E, and 2F, and an unused nutrient solution A storage tank 2G for storage and a cultivation floor 2H on which crops such as strawberries and tomatoes are planted are included.

  In the nutrient solution tank 2A, a nutrient solution before sterilization containing bacteria that have flowed out without being absorbed by plants etc. on the cultivation floor 2H is stored, and in the nutrient solution tank 2B, the nutrient solution containing the bacteria is heated and sterilized, The nutrient solution after cooling is stored. In addition, the nutrient solution which is not absorbed by the plant or the like and flows out to the nutrient solution tank 2A, that is, the nutrient solution which can be recycled by the heat pump sterilizer 1, is 3 of the total nutrient solution amount used in the cultivation floor 2H. The remaining 70% deficiency is replenished with unused nutrient solution stored in the storage tank 2G. Further, the nutrient solution adjusting tank 2C is used in the cultivation floor 2H, and after the nutrient (fertilizer component) is absorbed by the crop, it is sterilized by the heat pump type sterilizer 1 so that the nutrient solution is insufficient. Is a device that adjusts the amount of nutrients in the nutrient solution by adding nitrogen, phosphorus, iron, etc., and the fertilizer components are stored in the addition devices 2D, 2E, and 2F, respectively, Accordingly, fertilizer components that need to be added are put into the nutrient solution adjusting tank 2C.

  The nutrient solution tank 2A includes a heat absorption side 32A of the heat recovery heat exchanger 32, a heating unit 5 of the heating heat exchanger 31, a buffer tank 6, and a flow path 4 provided with a pump 3. The heat radiation side 32B of the heat recovery heat exchanger 32, the cooling unit 9 of the cooling heat exchanger 33, and the three-way valve 42 as mode switching means are connected. Furthermore, one outlet of the three-way valve 42 is connected to the nutrient solution tank 2B via the flow path 43, thereby forming a nutrient solution circulation cycle. The other outlet of the three-way valve 42 is connected directly to the flow path 4 in which the pump 3 is interposed via the flow path 44. The heat recovery heat exchanger 32 exchanges heat between the nutrient solution before sterilization passing through the heat absorption side 32A and the nutrient solution after sterilization treatment passing through the heat dissipation side 32B. The buffer tank 6 is heated by the heating heat exchanger 31 so that the nutrient solution heated to a predetermined temperature (90 ° C. in the present embodiment) can be maintained at a certain temperature or higher for a certain time. Between the heating unit 5 and the heat radiating unit 32B of the heat recovery heat exchanger 32.

  The heat pump 1B includes a compressor 11, a heat radiating section 12 of a heating heat exchanger 31, an air radiator 46, an electric expansion valve 13 as a pressure reducing device, and a cooling heat exchanger via a refrigerant pipe 15. 33, the heat absorption part 14, the air heat exchanger 60, the bypass circuit 70 that bypasses the cooling heat exchanger 33 and flows the refrigerant to the air heat exchanger 60, and the refrigerant that controls the refrigerant flow to the bypass circuit 70 An electromagnetic valve 72 as a flow path control device is connected. The air heat exchanger 60 provided in the refrigerant circuit from the cooling heat exchanger 33 to the suction side of the compressor 11 is a heat exchanger for exchanging heat between the refrigerant and the air, and this air heat exchange. A blower 60 </ b> F for heat exchange for passing air through the air heat exchanger 60 is installed in the vicinity of the heat exchanger 60. The air radiator 46 is provided on the outlet side of the heat exchanger 31 for heating, and is an auxiliary heat radiating portion for exchanging heat between the refrigerant and the air, and a cooling fan 46F is provided in the vicinity thereof.

Here, in the heat exchanger 31 for heating, the refrigerant flowing through the heat dissipating unit 12 is provided so as to face the nutrient solution flowing through the heating unit 5 through which the nutrient solution circulates. Moreover, also in the heat exchanger 33 for cooling, the refrigerant | coolant which flows through the heat absorption part 14 is provided in heat exchange with the cooling part 9 through which a nutrient solution circulates. The compressor 11 is a rotary compressor in which an electric element (motor) and a rotary compression element driven by the electric element (motor) are housed in an airtight container. In the present embodiment, the heat pump 1B is filled with carbon dioxide (CO ₂ ), which is a natural refrigerant, in consideration of flammability and toxicity as a refrigerant. Further, when carbon dioxide is used as a refrigerant, it is easier to obtain a higher temperature than conventional refrigerants such as chlorofluorocarbon, and in particular, a high temperature required for sterilization of nutrient solution in the heat exchanger 31 for heating, for example, + 90 ° C. Can be easily obtained.

  In FIG. 1, reference numeral 50 denotes a temperature sensor that detects the temperature (temperature B) of the nutrient solution flowing out from the heat exchanger 31 for heating. Based on the temperature of the nutrient solution detected by the temperature sensor 50, the pump 3 It is controlled. Reference numeral 51 denotes a temperature sensor that detects the temperature (temperature A) of the nutrient solution flowing out from the cooling heat exchanger 33. Based on the temperature detected by the temperature sensor 51, the operation control of the blower 46F of the air radiator 46 is performed. Has been done.

  Reference numeral 52 denotes a temperature sensor that detects the temperature of the nutrient solution flowing into the heating heat exchanger 31, and the operation of the compressor 11 is controlled based on the temperature detected by the temperature sensor 52. 53 is a refrigerant temperature sensor that detects the temperature of the refrigerant discharged from the compressor 11, and the opening degree of the expansion valve 13 is controlled based on the temperature detected by the refrigerant temperature sensor 53. Furthermore, 55 detects the temperature of the refrigerant flowing into the air heat exchanger 60.

  Reference numeral 54 denotes an outside air temperature sensor. Based on the temperature (outside air temperature) detected by the outside air temperature sensor 54, the control unit 80 uses a solenoid valve for determining and controlling the sterilization mode in the sterilization of the path to be described in detail later. 72 and the three-way valve 42 are controlled.

  With the above configuration, the operation of the heat pump sterilizer 1 in the present embodiment will be described with reference to FIGS. 1 and 2.

Normal sterilization operation First, the normal sterilization operation will be described. This normal sterilization operation is an operation in which a nutrient solution as a sterilization target is heated and sterilized and then cooled and supplied to the use side (use medium) with a heat pump type sterilizer.

  When a stator coil of the electric element provided in the airtight container of the compressor 11 is energized from a terminal (not shown) provided in the compressor 11 of the heat pump 1B, the electric element is activated and a rotor (not shown) rotates. . By this rotation, a roller fitted in an eccentric portion provided integrally with a rotation shaft (not shown) rotates eccentrically in the cylinder of the rotary compression element. Thus, the low-pressure refrigerant gas sucked into the low-pressure chamber side of the cylinder is compressed by the operation of the roller and the vane to become a high-temperature and high-pressure refrigerant gas of, for example, + 120 ° C., and is discharged from the high-pressure chamber side of the cylinder. At this time, the refrigerant is compressed to the supercritical pressure.

  Here, at the time of starting of the compressor 11, the rotational speed of the blower 60F installed in the vicinity of the air heat exchanger 60 is controlled to be increased for a predetermined time from that during normal operation. That is, when the compressor 11 is stopped after the normal operation is performed, the refrigerant easily collects in the cooling heat exchanger 33 or the air heat exchanger 60 having the lowest temperature in the refrigerant circuit. Is restarted, it takes a considerable amount of time for the liquid refrigerant accumulated in the cooling heat exchanger 33 and the air heat exchanger 60 to vaporize into a normal refrigerant circuit state. In addition, the refrigerant may return as it is in the liquid state at the time of restart, and the compressor 11 may be liquid compressed and damaged.

  However, the refrigerant accumulated in the air heat exchanger 60 can be evaporated at an early stage by increasing the rotational speed of the blower 60F of the air heat exchanger 60 when the compressor 11 is started. Thereby, the state in the refrigerant circuit can be quickly led to a stable state. Further, the liquid refrigerant from the cooling heat exchanger 33 can also be evaporated by the air heat exchanger 60. Accordingly, it is possible to avoid the disadvantage that the liquid refrigerant is sucked into the compressor 11 when the compressor 11 is started.

On the other hand, the refrigerant discharged from the compressor 11 flows into the heat exchanger 31 for heating, where it is deprived of heat and cooled by exchanging heat with the nutrient solution to be sterilized. In this heat pump 1B, since the high pressure side becomes supercritical pressure, the refrigerant (CO ₂ ) is not liquefied in the heat exchanger 31 for heating and the temperature is lowered while maintaining the supercritical state.

  The refrigerant cooled by the heat radiating unit 12 of the heating heat exchanger 31 is further cooled by the air radiator 46 and then reaches the expansion valve 13. Note that the refrigerant is still in a supercritical state at the inlet of the expansion valve 13. The refrigerant is brought into a gas / liquid two-phase mixed state due to the pressure drop in the expansion valve 13 and flows into the cooling heat exchanger 33 in this state. Then, the refrigerant evaporates in the cooling heat exchanger 33, absorbs heat (pumps up heat) from the nutrient solution flowing through the cooling unit 9 of the cooling heat exchanger 33, cools the nutrient solution as a sterilization target, and then air It flows into the heat exchanger 60.

  As a result, the refrigerant discharged from the cooling heat exchanger 33 can be reliably gasified, so that the liquid back into which the liquid refrigerant is sucked into the compressor 11 is prevented, and the compressor 11 is liquid-compressed. The inconvenience of being damaged can be avoided.

  In addition, when the temperature of the nutrient solution flowing through the cooling unit 9 of the cooling heat exchanger 33 is very high, the refrigerant is overheated by absorbing heat from the nutrient solution, and the temperature measured by the temperature sensor 55 may be high. is there. In this case, the air is exchanged with air in the air heat exchanger 60, so that the air is deprived of heat and cooled to about + 20 ° C., which is the air temperature.

  As a result, the temperature of the refrigerant discharged from the cooling heat exchanger 33 can be cooled to the air temperature (about + 20 ° C.) by the air heat exchanger 60, and the temperature of the refrigerant sucked into the compressor 11. However, it is possible to avoid inconvenience that the compressor 11 is overheated or the electric element of the compressor 11 is overheated to cause deterioration or damage of the motor winding.

  In addition, the refrigerant | coolant which came out of the air heat exchanger 60 is again sucked in in the compressor 11, and the cycle compressed is repeated.

  On the other hand, the nutrient solution in the nutrient solution tank 2A is circulated at a rate of, for example, 2 L / min so that the temperature of the nutrient solution (temperature B) detected by the temperature sensor 50 is + 90 ° C. as described above. The pump 3 is operated so that the nutrient solution flows in the flow path portion 1A that is a cycle. That is, when the temperature of the nutrient solution (temperature B) is higher than + 90 ° C., the rotation speed of the pump 3 is increased so that the flow rate of the nutrient solution flowing in the flow path portion 1B becomes faster than 2 L / min. Further, when the temperature of the nutrient solution (temperature B) is lower than + 90 ° C., the rotational speed of the pump 3 is reduced so that the flow rate of the nutrient solution flowing in the flow path portion 1A is slower than 2 L / min. In this way, by controlling the operation of the pump 3 based on the output of the temperature sensor 50, the temperature of the nutrient solution (temperature B) is maintained at a predetermined temperature (in this embodiment, + 90 ° C.). It becomes possible to perform heat sterilization of nutrient solution.

  And the nutrient solution before sterilization of the nutrient tank 2A of the storage tank 2 flows into the heat absorption side 32A of the heat exchanger 32 for heat recovery by the pump 3, where the nutrient solution before sterilization is the heat exchanger for heating. Heat is taken from the nutrient solution flowing on the heat radiation side 32B of the heat recovery heat exchanger 32 after being sterilized by heat at 31, and heated. Then, the nutrient solution flowing out from the heat absorption part 32 </ b> A of the heat recovery heat exchanger 32 is conveyed to the heating heat exchanger 31. In this heating heat exchanger 31, the nutrient solution is heated to + 90 ° C. by exchanging heat with the refrigerant of the heat pump 1B as described above.

  The operation of the compressor 11 is controlled by a temperature sensor 52 that detects the temperature of the nutrient solution flowing into the heating heat exchanger 31. That is, when the nutrient solution temperature detected by the temperature sensor 52 is low, the rotational speed of the compressor 11 is increased. As a result, the temperature of the refrigerant discharged from the compressor 11 rises, so that the temperature of the nutrient solution that exchanges heat with the refrigerant in the heating heat exchanger 31 can be raised to the predetermined temperature (+ 90 ° C.). become.

  Further, when the temperature of the nutrient solution detected by the temperature sensor 52 is high, the rotational speed of the compressor 11 is decreased to suppress the temperature of the refrigerant discharged from the compressor 11. Thereby, the disadvantage that the nutrient solution passing through the heating heat exchanger 31 is overheated to a temperature higher than + 90 ° C. can be avoided.

  Furthermore, since the heat given from the refrigerant to the nutrient solution in the heat exchanger 31 for heating is compressed to a supercritical pressure and is due to a high-temperature refrigerant that does not condense, from the inlet to the outlet of the heat exchanger 31 for heating. The nutrient solution can be heated at a substantially uniform rate. Therefore, the temperature difference between the refrigerant and the nutrient solution is substantially uniform from the inlet to the outlet of the heat exchanger 31 for heating, energy loss during heat exchange is reduced, and efficient heat sterilization can be realized. It becomes like this.

  And the nutrient solution heated by the heat exchanger 31 for heating passes through the heat radiation side 32B of the heat exchanger 32 for heat recovery, where heat is taken away by exchanging heat with the nutrient solution before sterilization, To be cooled.

  As described above, the nutrient solution is heated to a high temperature (+ 90 ° C.) in the heating heat exchanger 31 and sterilized, and the heated nutrient solution is heated in a short time. When the temperature reaches the heat radiation side 32B of 32, there is a fear that the holding time of the nutrient solution at a high temperature is insufficient and sterilization is not sufficiently performed. Therefore, in the flow path portion 1A of the present embodiment, a buffer tank 6 as a nutrient solution storage portion is provided between the heating portion 5 of the heat exchanger 31 for heating and the heat radiation side 32B of the heat exchanger 32 for heat exchange. Arranged. This buffer tank 6 is provided so that the nutrient solution heated to the high temperature (+ 90 ° C.) by the heat exchanger 31 for heating can be maintained at a predetermined temperature (for example, + 85 ° C.) or higher for a certain period of time. Then, when the flow rate of the nutrient solution flowing through the flow path portion 1A is 2 L / min, the nutrient solution can be held at a predetermined temperature (+ 85 ° C.) or more for 3 minutes by setting the capacity of the buffer tank 6 to 6 L. The sterilization time of the nutrient solution at a high temperature can be secured sufficiently.

  Thus, before the nutrient solution is sufficiently sterilized, the temperature of the nutrient solution reaches the heat radiation side 32B of the heat exchanger 32 for heat exchange, and the sterilization process becomes incomplete. Can be avoided. In addition, although the high temperature holding time (sterilization time) of nutrient solution changes with sterilization subjects, the adjustment of the sterilization time should select the capacity of buffer tank 6 to the optimal capacity for the necessary sterilization time according to the kind of sterilization subject. It can be realized by changing the feed amount of the pump 3.

  The nutrient solution radiated on the heat radiation side 32B of the heat recovery heat exchanger 32 then flows into the cooling heat exchanger 33 and is further cooled by exchanging heat with the refrigerant of the heat pump 1B as described above. To a temperature of, for example, + 20 ° C.

  Here, the cooling temperature of the nutrient solution in the cooling heat exchanger 33 controls the operation of the blower 46F of the air radiator 46 based on the temperature sensor 51 that detects the temperature of the nutrient solution flowing out from the cooling heat exchanger 33. By doing so, it is controlled with high accuracy. That is, the operation of the blower 46F is controlled so that the temperature of the nutrient solution (temperature A) detected by the temperature sensor 51 is, for example, + 20 ° C. When the temperature of the nutrient solution (temperature A) is higher than + 20 ° C., the rotational speed of the blower 46F is increased to dissipate the refrigerant in the air radiator 46, and when it is lower than + 20 ° C., Control is performed so that the heat dissipation of the refrigerant in the air radiator 46 is reduced by reducing the rotational speed.

  Thereby, the temperature (temperature A) of the nutrient solution can be maintained at + 20 ° C. In particular, in the hydroponic cultivation system of the present embodiment, the high temperature nutrient solution (sterilization target) cannot be returned as it is to the cultivation floor where the crop is planted, so the heat pump sterilization device of the present invention is used. This is particularly effective when applied.

  The opening of the expansion valve 13 is controlled so that the refrigerant temperature detected by the refrigerant temperature sensor 53 is + 120 ° C.

  As described above, the bypass circuit 70 is a bypass circuit that bypasses the cooling heat exchanger 33 and flows the refrigerant to the air heat exchanger 60, and is controlled by the electromagnetic valve 72. That is, the electromagnetic valve 72 controls whether the refrigerant decompressed by the expansion valve 13 is allowed to flow to the cooling heat exchanger 33 or to the bypass circuit 70. When the temperature of the nutrient solution (heat absorption target) detected by the temperature sensor 51 becomes a predetermined freezing temperature, for example, + 5 ° C. or less, the solenoid valve 72 is opened and the refrigerant flows into the bypass circuit 70. On the other hand, when the temperature of the nutrient solution detected by the temperature sensor 51 is higher than + 5 ° C., the bypass circuit 70 is closed by the electromagnetic valve 72, so that the refrigerant decompressed by the expansion valve 13 is used as a cooling heat exchanger. It flows to 33.

  As described above, when the temperature of the nutrient solution detected by the temperature sensor 51 is + 5 ° C. or lower, the refrigerant decompressed by the expansion valve 13 passes through the bypass circuit 70 without flowing to the cooling heat exchanger 33. As a result, the nutrient solution is not cooled in the cooling heat exchanger 33. That is, it is possible to avoid the disadvantage that the nutrient solution is excessively cooled by the cooling heat exchanger 33 and the temperature of the nutrient solution is lowered to + 5 ° C. or less, which is a freezing temperature. Thereby, the inconvenience that a nutrient solution freezes can be avoided beforehand.

  The refrigerant that has passed through the bypass circuit 70 flows into the air heat exchanger 60 as described above, absorbs heat from the air blown by the blower 60F, evaporates by exhibiting a cooling action, and is then compressed again. Repeat the cycle of being sucked into 11.

  In this way, by allowing the refrigerant decompressed by the expansion valve 13 to flow from the bypass circuit 70 to the air heat exchanger 60, the refrigerant is evaporated without passing through the cooling heat exchanger 33, and a predetermined temperature ( + 20 ° C.) and a gas state. Even in this case, the state of the refrigerant sucked into the compressor 11 can be optimized.

  Further, in the present embodiment, the bypass circuit 70 bypasses only the cooling heat exchanger 33. However, the present invention is not limited to this, and this is a case where the expansion valve 13 is also bypassed simultaneously as shown by a broken line in FIG. It doesn't matter.

  Then, when the sterilization process (normal sterilization operation) of the nutrient solution in the nutrient solution tank 2A and the nutrient solution tank 2B is completed, the operator stops the operation of the pump 3 and stops the operation of the heat pump 1B. At this time, the nutrient solution in the flow path portion 1A such as the flow path 4, the heat recovery heat exchanger 32, the heating heat exchanger 31, and the cooling heat exchanger 33 remains inside due to the pump 3 being stopped. To do. Then, until the pump 3 is operated next time and the sterilization process is resumed, it is normally maintained at room temperature. Therefore, the nutrient solution remaining in these flow paths 1B grows a large amount of bacteria during the rest period until the start of the next sterilization treatment even if only a few bacteria remain at the end of the operation. . And since the nutrient solution mixed with a large amount of bacteria flows into the nutrient solution tank 2B during the next sterilization operation, the effectiveness of the sterilization treatment of the nutrient solution may be lost.

Pre-sterilization (first route sterilization mode)
Therefore, pre-sterilization as the first path sterilization mode will be described next. This pre-sterilization is a path sterilization mode for sterilizing the inside of the flow path portion 1A left at room temperature for a long time, and the heat sterilization in the flow path portion 1A is executed immediately before the start of the above-described normal sterilization operation. Is the method. As in the case of the normal sterilization operation, the heat pump 10 starts operation, compresses the refrigerant to an appropriate supercritical pressure, and then discharges it to the heat exchanger 31 for heating. In the heat exchanger 31 for heating, the refrigerant is cooled by depriving heat by exchanging heat with the nutrient solution.

  The high-pressure side refrigerant cooled by the heating heat exchanger 31 flows into the air radiator 46 and then flows into the expansion valve 13, the cooling heat exchanger 33, or the bypass circuit 70. Here, in this pre-sterilization, the electromagnetic valve 72 is opened or the expansion valve 13 is fully opened. As a result, no endothermic action is generated in the cooling heat exchanger 33 and heat exchange between the refrigerant and the nutrient solution is hardly performed, so that the nutrient solution is not cooled.

  Then, the refrigerant exiting the cooling heat exchanger 33 enters the air heat exchanger 60 where heat is dissipated by exchanging heat with the surrounding air, and the cycle of being sucked into the compressor is repeated.

  On the other hand, the nutrient solution in the flow path section 1A constituted by the flow path 4, the heat recovery heat exchanger 32, the heating heat exchanger 31, and the cooling heat exchanger 33 is the three-way valve 42 in the pre-sterilization. Since it is switched to the flow path 44 side, for example, it flows from the pump 3 to the heat absorption side 32A of the heat recovery heat exchanger 32 at a rate of 2 L / min. Deprived of heat from the heated nutrient solution and receives a heating action. Then, the nutrient solution flowing out from the heat absorption side 32 </ b> A of the heat recovery heat exchanger 32 is conveyed to the heating heat exchanger 31. In the heating heat exchanger 31, the nutrient solution is heated to a predetermined temperature by exchanging heat with the high-temperature refrigerant of the heat pump 1B as described above.

  Even in such pre-sterilization, since the heat given from the refrigerant to the nutrient solution in the heat exchanger 31 for heating is the heat by the high-temperature refrigerant compressed to the supercritical pressure, from the inlet to the outlet of the heat exchanger 31 for heating. The nutrient solution can be heated at a substantially uniform rate. As a result, the temperature difference between the refrigerant and the nutrient solution is substantially uniform from the inlet to the outlet of the heat exchanger 31 for heating, energy loss during heat exchange is reduced, and the buffer tank 6 maintains a high temperature state. Thus, efficient heat sterilization can be realized.

  Then, the nutrient solution heated in this way passes through the heat radiation side 32B of the heat exchanger 32 for heat recovery, where heat is deprived by heat exchange with the nutrient solution before the heat sterilization treatment and is slightly cooled. The Thereafter, the nutrient solution flows into the cooling heat exchanger 33 where heat exchange is not performed as described above, and is sent again to the heat recovery heat exchanger 32 by the pump 3 through the three-way valve 42. As a result, the nutrient solution in the channel portion 1A is heated while circulating as described above. In this embodiment, the nutrient solution in the channel portion 1A is increased until the temperature detected by the temperature sensor 51 reaches + 60 ° C. Circulation heating is performed. At this time, the pressure in the flow path portion 1A rises because the temperature of the internal nutrient solution is raised, but the nutrient solution tank is connected between the pump 3 and the channel 44 connected to the three-way valve 42. Since the 2A channel 4 is open and connected, an excessive pressure rise can be prevented.

  As described above, in the pre-sterilization, the cooling of the nutrient solution is stopped in the cooling heat exchanger 33, and the nutrient solution discharged from the cooling heat exchanger 33 is not returned to the nutrient tanks 2A and 2B. Since it circulates directly to the heat exchanger 32 for heat recovery, the heat exchanger 31 for heating, etc., the nutrient solution remaining in the flow path section 1A can be effectively sterilized by heating.

  Therefore, after the above-described normal sterilization operation is stopped, even if the residual nutrient solution in the channel portion 1A is left to stand and the bacteria grow, the residual nutrient solution in the channel portion 1A is heated by pre-sterilization. After the sterilization is performed, the residual liquid in the flow path portion 1A is sent to the nutrient solution tank 2B, so that it is possible to avoid contamination of the bacteria into the nutrient solution tank 2B and 2A.

  Thereafter, when the temperature detected by the temperature sensor 51 reaches + 60 ° C. as described above, the cooling of the nutrient solution in the cooling heat exchanger 33 is resumed by closing the electromagnetic valve 72. In the cooling of the nutrient solution, the nutrient solution passed through the cooling heat exchanger 33 is directly circulated through the heat recovery heat exchanger 32 and the heating heat exchanger 31 without returning to the nutrient tanks 2A and 2B. Since cooling is performed in the heat exchanger 33, the nutrient solution in the flow path portion 1A heated by the previous sterilization can be brought close to the temperature in the normal sterilization operation.

  As will be described in detail later, when the pre-sterilization is performed, the outside air temperature measured by the outside air temperature sensor 54 is determined by the control unit 80, and it is determined that the outside air temperature is equal to or higher than the predetermined temperature and the pre-sterilization is necessary. At times, the solenoid valve 72 or the expansion valve 13 and the three-way valve 42 are controlled as described above to perform pre-sterilization.

Post sterilization (second route sterilization mode)
Next, post sterilization as the second path sterilization mode will be described. The sterilization after this is different from the above-mentioned pre-sterilization for sterilizing the inside of the flow path portion 1A left at room temperature for a long time, and immediately after the normal sterilization operation, before the nutrient solution is left at room temperature for a long time, the flow path portion 1B. It is a method of performing sterilization inside. That is, post sterilization is a sterilization method of performing sterilization in the flow path portion 1A immediately after the end of the normal sterilization operation described above. In particular, after the end of the normal sterilization operation, the outside air temperature until the next normal sterilization operation is low, This is a path sterilization mode that is preferably used in winter when there is little growth of bacteria in the flow path section 1A.

  In post-sterilization, after the normal sterilization operation as described above is completed and before the operation of the pump 3 and the heat pump 1B is stopped, the three-way valve 42 is first switched to the flow path 44 side in the same manner as the pre-sterilization, and the heat pump 1B. The electromagnetic valve 72 is opened or the expansion valve 13 is fully opened. Thereby, the sterilization process substantially the same as the said pre-processing is performed with respect to a nutrient solution.

  Since the post-sterilization is performed immediately after the end of the normal sterilization operation as described above, the nutrient solution in the flow path portion 1A, particularly the heat exchanger 31 for heating and the heat exchanger 32 for heat recovery, are used at the start of post-sterilization. The nutrient solution between the heat radiation side 32B and the heat release side 32B is at a high temperature. For this reason, since path sterilization can be performed by effectively using the heat (residual heat) applied to the nutrient solution in normal sterilization operation, power consumption can be suppressed compared to pre-sterilization, and more efficient sterilization is possible. At the same time, the route sterilization time can be greatly shortened.

  The operation flow of the heat pump type sterilizer 1 of this embodiment provided with the above three types of sterilization operations, that is, the normal sterilization operation, the pre-sterilization operation, and the post-sterilization will be described in detail below.

  FIG. 2 shows an operation flow of the heat pump sterilizer 1 of this embodiment. The operation of the heat pump sterilizer 1 includes pre-sterilization 101, normal sterilization operation 102, post-sterilization 103, Driving judgment based on the temperature measurement 110. In addition, although a present Example demonstrates from the case where the pre-sterilization 101 is performed first, the heat pump sterilization apparatus 1 of this invention does not necessarily need to start an operation | movement from the pre-sterilization 101. FIG.

  First, after the inside of the flow path portion 1A is sterilized by the pre-sterilization 101, an operation of sterilizing the nutrient solution by heating and cooling and supplying it to the use medium, that is, a normal sterilization operation 102 is performed. When the normal sterilization operation ends, the heat pump sterilizer 1 is left in a stopped state until the next normal sterilization operation 102 is started, for example, at night.

  Thereafter, an outside air temperature measurement 110 is performed by the outside air temperature sensor 54. And when outside air temperature is 15 degreeC or more (for example, summer season etc.), as above-mentioned, the possibility that the microbe propagated in the flow-path part 1A is high while the heat pump type sterilizer 1 stops at night. Therefore, in such a case, the pre-sterilization 101 is performed again, and the normal liquid sterilization operation 102 is performed after the nutrient solution in the flow path portion 1A is sterilized. And after completion | finish of the normal sterilization driving | operation 102, the sterilization process of the nutrient solution by the heat pump type sterilizer 1 is performed in order of the external temperature measurement 110 again (procedure A).

  On the other hand, when the outside temperature is less than 15 ° C. in the outside temperature measurement 110 (for example, in winter), it is determined that there is a high possibility that the bacteria are not growing even when the heat pump sterilizer 1 is stopped at night or the like. The normal sterilization operation 102 is performed without performing the pre-sterilization 102. Even when it is determined that the outside air temperature is low and the growth of the bacteria is small even when the heat pump sterilization apparatus 1 is stopped at night or the like, the cooling heat exchanger 33 or the like is normally used during the sterilization operation 102. Therefore, after the end of the normal sterilization operation 102, the post sterilization 103 is always performed, and then the outside air temperature measurement 110 is performed again (procedure B). ), The nutrient solution is sterilized by the heat pump sterilizer 1.

  In addition, depending on the result of the outside air temperature measurement 110 in the procedure A and the procedure B, when the operation is repeated from the procedure A to the procedure B or from the procedure B to the procedure A, and when only the procedure A or only the procedure B is continuously performed , Will happen.

  Next, with reference to FIG. 3, the 2nd Example of the heat pump type sterilizer of this invention is described. FIG. 3 shows an operation flow of the heat pump type sterilizer in this case. In this embodiment, the same reference numerals as those in the first embodiment have the same or similar functions and effects. Suppose it is a thing.

In FIG. 3, the stop state determination 120 is a determination unit that determines the next driving operation in consideration of various states when the heat pump sterilizer 1 is stopped at night or the like in the first embodiment. The operation of the heat pump sterilizer 1 in this case will be described.

  First, in the same manner as in the first embodiment, after the inside of the flow path portion 1A is sterilized by the pre-sterilization 101, the operation of sterilizing the nutrient solution by heating and cooling it is supplied to the use medium, that is, the normal sterilization operation 102 is performed. To be implemented. When the normal sterilization operation ends, the heat pump sterilizer 1 is left in a stopped state until the next normal sterilization operation 102 is started, for example, at night.

  Thereafter, stop state determination 120 is performed. In the first embodiment, after the heat pump sterilizer 1 is stopped, the next operation is determined by measuring the outside air temperature before the next normal sterilization operation 102 or the previous sterilization 101. Measure and calculate the accumulated outside air temperature and the average outside air temperature, etc., and if this result exceeds a predetermined value, the bacteria may have proliferated in the flow path section 1A while the heat pump sterilizer 1 is stopped at night Judgment is high. Therefore, in such a case, the pre-sterilization 101 is performed again, and the nutrient solution in the flow path portion 1A is sterilized, and then the normal sterilization operation 102 is performed. And after completion | finish of the normal sterilization driving | operation 102, the sterilization process of the nutrient solution by the heat pump type sterilizer 1 is performed in order of the external temperature measurement 110 again (procedure A).

  On the other hand, when the result of measurement and calculation of the accumulated outside air temperature or the average outside air temperature during the stop is less than a predetermined value, it is determined that there is a high possibility that the bacteria are not growing even when the heat pump sterilizer 1 is stopped at night or the like. However, the normal sterilization operation 102 is performed without performing the pre-sterilization 102. In such a case, that is, in the case where it is determined that the growth of the bacteria is small even when the heat pump sterilizer 1 is stopped at night or the like, the cooling heat exchanger 33 and the like are compared during the normal sterilization operation 102. Since there is a possibility that the bacteria may grow in the flow path having a low general nutrient solution temperature, after the normal sterilization operation 102 is finished, the post sterilization 103 is always performed, and then the outside air temperature measurement 110 is performed again (procedure B). Then, the nutrient solution is sterilized by the heat pump sterilizer 1.

  In this embodiment, as in the first embodiment, the operation is repeated from the procedure A to the procedure B or from the procedure B to the procedure A according to the result of the outside air temperature measurement 110 in the procedure A and the procedure B. There are cases where only procedure A or procedure B is always performed.

  Thereby, in this embodiment, since the next operation determination after the normal sterilization operation 102 is determined by the integrated temperature or the average temperature when the heat pump sterilizer 1 is stopped at night or the like, more accurate sterilization is performed. Processing is possible.

  Next, a third embodiment of the heat pump sterilizer of the present invention will be described with reference to FIG. FIG. 4 shows a schematic configuration diagram of the heat pump type sterilizer 1 in this case. In this embodiment, the same reference numerals as those in the first and second embodiments are the same or similar functions. Suppose that it has an effect.

  In FIG. 4, 34 is a heater and is arrange | positioned so that the nutrient solution in the flow-path part 1A can be heated. The heater 34 can be disposed anywhere as long as the nutrient solution in the flow path 1A can be heated, but is preferably provided in the vicinity of the cooling unit 9.

  The heater 34 heats the nutrient solution in the flow path section 1A instead of the heat pump 1B as the nutrient solution heating sterilization means in the pre-sterilization and post-sterilization as the first and second path sterilization modes in each of the above embodiments. Used as a means, but preferably used in post sterilization. As a result, in post-sterilization, after the normal sterilization operation is completed, the pump 3 remains driven, and even if the operation of the heat pump 1B is stopped, the heat (residual heat) applied to the nutrient solution in the normal sterilization operation by the heater 34. ) Can be sterilized by effectively heating the vicinity of the heat exchanger 33 for cooling, which has a particularly low temperature after the normal sterilization operation.

  The heater 34 may be used simultaneously with the heat pump 1B in the pre-sterilization and the post-sterilization. In this case, particularly the vicinity of the cooling heat exchanger 33 is effectively heated by the heater 34, so that the pre-sterilization and post-sterilization operation time can be shortened.

  As described in detail above, according to each of the above embodiments of the present invention, the nutrient solution can be cooled immediately using the heat absorption part of the heat pump after the nutrient solution is heat sterilized. After that, it is very effective in the recirculating hydroponic cultivation system as in each of the above embodiments where the nutrient solution cannot be returned at a high temperature.

  In addition, the heat pump heat treatment apparatus of the present invention is not only used for sterilization of nutrient solution for hydroponic cultivation systems as in the above embodiments, but can also be applied to beverages such as juice and milk. In particular, in beverages such as juice and milk, since sterilization that does not impair the flavor is necessary, it becomes possible to cool immediately after heating by applying a sterilizer using the heat pump heat treatment apparatus of the present invention, The heat sterilization process can be performed without impairing the flavor of the beverage.

  Moreover, in each said Example, although heat sterilization temperature was 90 degreeC, in beverages, such as the above, juice, milk, etc., when sterilization at lower temperature is required, in heat pump 1B, It is possible to easily obtain the necessary heat sterilization temperature by adjusting the expansion valve 13 or changing the charging pressure of the refrigerant.

It is the structure schematic which showed one Embodiment of the processing apparatus of this invention. It is a flowchart which shows the operation | movement flow of 1st Embodiment of the processing apparatus of this invention. It is a flowchart which shows the operation | movement flow of 2nd Embodiment of the processing apparatus of this invention. It is the structure schematic which showed 3rd Embodiment of the processing apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Heat pump type sterilizer 1A Flow path part 1B Heat pump 2 Reservoir 2A, 2B Nutrient solution tank 3 Pump 4 Channel 5 Heating part 6 Buffer tank 9 Cooling part 11 Compressor 12 Heat radiation part 13 Expansion valve 14 Heat absorption part 15 Refrigerant piping 31 Heat exchanger for heating 32 Heat exchanger for heat recovery 33 Heat exchanger for cooling 34 Heater 42 Three-way valve 43, 44 Flow path 46 Air radiator 50, 51, 52, 53, 55 Temperature sensor 54 Outside temperature sensor 60 Air heat Exchanger 80 Control unit

Claims (10)

A flow path through which the fluid to be heated circulates, heating means for heating the fluid in the flow path, and utilization means for using the fluid heated by the heating means,
A first heating mode in which after the fluid is heated by the heating means, a process of supplying the heated fluid to the profit means is performed across a predetermined pause period;
In the heat treatment apparatus, the second heating mode for heating the fluid in a state in which the supply of the fluid to the utilization unit is stopped in the pause period,
The heat treatment apparatus, wherein the second heating mode is performed in the first half of the pause period. A cooling means for cooling the fluid heated by the heating means before supplying the fluid to the utilization means;
The heat treatment apparatus according to claim 1, wherein the second heating mode is executed in a state where cooling of the fluid by the cooling means is stopped. A refrigeration circuit including a compressor, a heat radiating portion, a heat absorbing portion, and an expansion means;
A heating unit that is connected to the heat radiating unit and heats the object to be heated using heat radiation from the refrigeration circuit, and a heating object that is connected to the heat absorption unit and heated by the heating unit using the heat absorption of the refrigeration circuit. A heating means including a cooling means for cooling, and
A normal heating operation in which the heating object is heated by the heating means, and then the heating object is conveyed to the cooling means and cooled, and a predetermined pause period is performed;
And a flow path heating operation for heating the heating target in a state in which the heat absorption by the heat absorption unit is reduced or stopped in the pause period.   The heat treatment apparatus according to claim 3, wherein the flow path heating operation is performed in the first half of the pause period. A temperature sensor that measures the temperature of the heating object between the heating means and the cooling means; and an outside air temperature sensor that measures the outside air temperature,
The flow path heating operation is executed before the temperature of the heating target measured by the temperature sensor during the pause period is lowered to the outside air temperature measured by the outside air temperature sensor. The heat processing apparatus as described in. A refrigeration circuit including a compressor, a heat radiating portion, a heat absorbing portion, and an expansion means;
A heating unit that is connected to the heat radiating unit and heats the object to be heated using heat radiation from the refrigeration circuit, and a heating object that is connected to the heat absorption unit and heated by the heating unit using the heat absorption of the refrigeration circuit. Cooling means for cooling, a heating target flow path including:
An outside air temperature sensor,
In the heat treatment apparatus for performing a normal heating operation in which the heating object is heated by the heating means, and then the heating object is transported to the cooling means and cooled over a predetermined pause period.
Measuring the outside air temperature with the outside air temperature sensor during the rest period,
When the outside air temperature is equal to or higher than a predetermined value, a first operation for performing the normal heating operation is performed after the flow path heating operation for heating the heating target in a state where the heat absorption by the heat absorption unit is reduced or stopped. Run the mode
When the outside air temperature is less than a predetermined value, the second operation mode in which the normal heating operation is performed without performing the flow path heating operation is performed.   The heat treatment apparatus according to claim 6, wherein the measurement of the outside air temperature by the outside air temperature sensor is performed in the latter half of the pause period.   The heat treatment apparatus according to any one of claims 2 to 7, further comprising a storage unit that can store the heating target between the heating unit and the cooling unit. A refrigeration circuit including a compressor, a heat radiating portion, a heat absorbing portion, and an expansion means;
A heating unit that is connected to the heat radiating unit and heats the object to be heated using heat radiation from the refrigeration circuit, and a heating object that is connected to the heat absorption unit and heated by the heating unit using the heat absorption of the refrigeration circuit. Cooling means for cooling, a heating target flow path including:
A storage unit that can store the heating object disposed between the heating unit and the cooling unit;
The heating target is heated by the heating unit, stored in the storage unit, and then transferred to the cooling unit and cooled. The sterilization apparatus using the heat treatment apparatus according to claim 1, wherein the heating target includes bacteria, and the bacteria are sterilized by the heating means.

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