JP4917467B2 - Refrigerator system - Google Patents

Description

The present invention relates to a refrigeration system for use in such an air conditioner.

Conventionally, this kind of refrigerator system manufactures the cold water used by the air conditioning apparatus of comparatively large capacity | capacitances, such as a central type air conditioning apparatus of an office building, a semiconductor factory, etc. (for example, refer patent document 1).
One example will be described with reference to FIG.
For example, chilled water used in the cooling coil 8 of the air conditioner 7 such as a central air conditioner in an office building or a relatively large capacity air conditioner such as a semiconductor factory is cooled by the evaporator of the refrigerator 1 and the circulation pump 2. As shown by the arrow, it is conveyed on the cold water going path through the going header 5. The cold water heated by the cooling coil 8 of the air conditioner 7 returns from the cold water return path to the refrigerator 1 via the return header 6 as indicated by the arrow. The refrigerator 1 constitutes a refrigeration cycle that uses the latent heat of evaporation of refrigerant gas such as an evaporator, a compressor, a condenser, an expansion valve, and an evaporator, and a cooling water pump from a cooling tower 3 installed outdoors. As shown by the arrow through 4, the cooling water conveyed in the cooling water going path is introduced into the condenser of the refrigerator 1, is heat-exchanged with the refrigerant of the refrigeration cycle, is heated, and is cooled by the cooling water return path. 3 is conveyed. Then, the cooling water which is cooled by exchanging heat with the atmosphere in the cooling tower 3 is conveyed through the cooling water going path via the cooling water pump 4 as indicated by arrows. When a plurality of refrigerators 1 and cooling towers 3 are used in combination, each refrigerator 1 is connected to a forward header 5 and a return header 6 and is connected to a condenser of each refrigerator 1. The forward path and the cooling water return path are each connected to a plurality of cooling towers, or connected together to a large collective cooling tower.
FIG. 3 of JP-A-10-9796

However, in the cooling water system on the condenser side of the conventional refrigerator system, the condenser of the refrigerator 1, the cooling tower 3, and the cooling water pump 4 are connected by a single pipe to form an independent closed circuit. Therefore, even if any device in the circuit malfunctions, the independent system falls into a disconnected state, and even if a plurality of systems are arranged in parallel, there is a possibility that a large output shortage occurs. Further, even if one device in the system is regularly maintained even if the device is not malfunctioning, the entire system must be stopped.
The present invention was made in order to solve such a conventional problem, and its purpose is to provide a refrigerator and a cooling tower via a cooling water tank in the cooling water system on the condenser side of the refrigerator system. Even if a malfunction occurs in any one of a plurality of refrigerators, one of a plurality of cooling towers, or one of a plurality of cooling water pumps. It is an object of the present invention to provide a refrigerator system in which maintenance can be freely performed without causing a large output shortage by rearranging and backing up normal devices of the same type and other devices.

  In the cooling water system on the condenser side of the refrigerator system, the invention according to claim 1 is a refrigerator circuit having a refrigerator and a cooling water pump, a cooling tower circuit having a cooling tower and a cooling tower pump, and low-temperature water. A cooling water tank partitioned into a water tank, a medium-temperature water tank and a high-temperature water tank, the refrigerator circuit is arranged between the medium-temperature water tank and the high-temperature water tank, and the cooling tower circuit is for low-temperature water The tank interval wall, which is arranged between the water tank and the hot water tank and separates the low temperature water tank and the medium temperature water tank, provides an opening for dropping the cooling water from the low temperature water tank to the medium temperature water tank. A shelf that guides cooling water flowing out from the opening of the low temperature water tank between the tank interval wall that partitions the water tank and the intermediate temperature water tank and the tank interval wall that partitions the intermediate temperature water tank and the high temperature water tank Low temperature water tank using the difference in water level between the low temperature water tank and the medium temperature water tank A weir is formed at the tip of the shelf to form a waterfall that drops cooling water into the medium-temperature water tank, and the tank separation wall that separates the medium-temperature water tank and the high-temperature water tank contains cooling water from the high-temperature water tank. For high-temperature water, an opening is provided to drop into the hot water tank, and between the tank interval wall that separates the low-temperature water tank and the medium-temperature water tank, and the tank interval wall that separates the medium- and high-temperature water tanks. In addition to providing a shelf to guide the cooling water flowing out from the tank opening, a waterfall is formed that drops cooling water from the high-temperature water tank to the medium-temperature water tank using the difference in water level between the high-temperature water tank and the medium-temperature water tank. The weir to be provided is provided at the tip of the shelf.

According to a second aspect of the present invention, in the refrigerator system according to the first aspect, the opening provided in the tank interval wall that separates the low temperature water tank and the intermediate temperature water tank includes the high temperature water tank and the intermediate temperature water tank. It is located higher than the opening provided in the tank space | interval wall which partitions off.
The invention according to claim 3 is the refrigerator system according to claim 1 or claim 2, wherein a tank interval wall that partitions the low-temperature water tank and the medium-temperature water tank, a medium-temperature water tank, and a high-temperature water tank. The two shelves provided between the partitioning wall and the partition wall are provided so as to be flush with the lower end of the opening.
According to a fourth aspect of the present invention, in the refrigerator system according to any one of the first to third aspects, a heat exchanger circuit having a heat exchanger and a circulation pump is connected to a high-temperature water tank and a low-temperature water tank. It is characterized by being arranged between.

In the cooling water system on the condenser side of the refrigeration system, the cooling tower capacity changes greatly with the seasonal fluctuation of the outside air temperature, and the cooling water temperature fluctuates greatly. The capacity of the refrigerator, cooling water pump, and cooling tower of the refrigerator system is selected according to the total cooling load during the summer when the building load and the outdoor air load are the highest. Therefore, if the outside air temperature decreases in seasons other than summer, the capacity of the cooling tower using outside air as a heat source will increase, but the building load and outside air load will decrease, resulting in excessive equipment capacity. . Therefore, part of the cooling tower is stopped during the intermediate period and winter period, and the total flow rate of the cooling water pump can be reduced.
Refrigerators increase in efficiency by reducing the capacity of the compressor against the decrease in cooling water temperature introduced into the condenser due to the increased capacity of the cooling tower and the decrease in the outside air temperature at times other than summer, The coefficient of performance (COP) = the amount of heat taken by the evaporator (kcal) / (the amount of power required for the compressor (KW) × 860 (kcal / KW)) is improved, and the power consumption can be reduced.
Therefore, in the present invention, in order to operate the refrigerator with high efficiency with respect to the refrigerator load other than the peak load time in summer, the cooling water system is not a closed system but a cooling water tank is installed to collect the cooling water once. Controlling the number of operating units, including stopping the cooling tower fan and cooling water pump so as to manage the cooling water temperature of the aquarium, enables efficient operation of the cold heat source equipment and energy saving.

Moreover, in a cold heat source system, since normally one independent closed circuit of a refrigerator, a cooling tower, and a pump is formed, the independent system falls into a disconnected state regardless of which device in the circuit is malfunctioning. . In addition, in the case where one device in the system is maintained, the entire system is stopped.
On the other hand, in the cooling water system on the condenser side of the refrigeration system, the present invention divides the chiller and the cooling tower through the cooling water tank so as to be divided and independent for each device. Even if one of the cooling towers, one of the cooling towers, or one of the cooling water pumps malfunctions, the other normal devices of the same type and other devices should be backed up. It is an object of the present invention to provide a refrigerator system and a cooling water tank that do not fall into a large output shortage and can be maintained freely. For this reason, since it can be handled as a refrigerator group including a cooling water pump and a cooling tower group including a cooling water pump, if there is one spare machine in each group, the periodic maintenance can be performed even at the maximum load. It is possible to operate the equipment for the maximum load capacity in total, and it can respond properly, and there is no shortage of output.

According to the present invention, in the winter or intermediate period, in the case where the front heating load for humidifying the outside air in the outdoor air conditioner or the use of hot water occurs, the exhaust heat on the condenser side of the refrigerator is reduced. Since it is collected once in the high temperature water tank of the cooling water tank, it can be used as a heating heat source by connecting the load and the cooling water tank low temperature water tank through a separate circulation path and circulating with a pump. Can be combined with a reduction in the number of cooling towers in operation, reducing energy consumption. Since the exhaust heat on the condenser side of the refrigerator is about 37 ° C., sufficient pre-heating is possible to humidify the outside air in the outdoor air conditioner and to humidify the water up to the 11 ° C. dew point required by semiconductor manufacturing factories. I can cover it.
According to the present invention, the refrigerator and the cooling tower do not form a fixed pair by forming a closed circuit with the piping, and the refrigerator group and the cooling tower group can be formed as separate piping systems. A cooling tower group is formed by combining cooling towers having different characteristics, and white smoke prevention and road surface freezing prevention measures can be efficiently performed according to weather conditions.

  According to the present invention, when the exhaust heat of the by-product generated in the refrigeration cycle condenser of the refrigerator intended for cooling is used as a heating heat source, the exhaust heat remaining without partitioning is dissipated to the atmosphere in the cooling tower. In the case of, etc., a cooling water tank as a buffer that absorbs sudden changes in water temperature is interposed, so that the heat capacity of refrigerators, cooling towers, cooling coils, heating heat exchangers, heating coils, pipes and automatic control of them The risk of disturbance in the heat source system can be avoided due to the characteristics of the control system. Similarly, a cooling water tank as a buffer that absorbs sudden changes in water temperature intervenes to enable switching to maintain the system with high efficiency against fluctuations in load and weather conditions, as well as periodic maintenance and equipment. It is possible to suppress the occurrence of turbulence in the entire cooling water system of the refrigerator system due to switching of operating equipment due to trouble.

Hereinafter, the present invention will be described based on embodiments shown in the drawings.
1 to 5 show a refrigerator system 10 and a cooling water tank 50 according to an embodiment of the present invention.
The refrigerator system 10 according to this embodiment includes three refrigerator circuits 20a, 20b, and 20c, three cooling tower circuits 30a, 30b, and 30c, two heat exchanger circuits 40a and 40b, and a low-temperature water tank. 51, a cooling water tank 50 partitioned into a medium temperature water tank 52 and a high temperature water tank 53.

The three refrigerator circuits 20a, 20b, and 20c have refrigerators 21, 23, and 25 and cooling water pumps 22, 24, and 26, respectively, and are arranged between the medium-temperature water tank 52 and the high-temperature water tank 53. ing. The cooling water pumps 22, 24, and 26 may be driven by a frequency control motor using an inverter that can control the rotational speed in order to adjust the flow rate.
The three cooling tower circuits 30 a, 30 b, 30 c have cooling towers 31, 33, 35 and cooling tower pumps 32, 34, 36, respectively, and are arranged between the low-temperature water tank 51 and the high-temperature water tank 53. Has been. The cooling tower pumps 32, 34, and 36 may be driven by a frequency control motor using an inverter that can control the number of revolutions in order to adjust the flow rate.

  The two heat exchanger circuits 40 a and 40 b have heat exchangers 41 and 43 and circulation pumps 42 and 44, and are arranged between the high temperature water tank 53 and the low temperature water tank 51. Here, the heat exchangers 41 and 43 generally use high-temperature cooling water pumped from a high-temperature water tank as a heating heat source for heating the heat medium (air or water) on the secondary side of the heat exchanger to about 30 ° C. Used for. The temperature of the high-temperature cooling water can be raised to a maximum of about 37 ° C., which is the rated outlet water temperature on the condenser side of a normal refrigerator. In some special refrigerators, the temperature at the outlet of the condenser supplied to the high-temperature water tank is raised to 40 ° C. or higher. By using this, the temperature of the high-temperature cooling water can be raised to about 40 ° C. The heat exchangers 41 and 43 can be used for heating pure water by using this high-temperature cooling water as a heat source and flowing pure water to the secondary side of the heat exchanger. If the intake air flows to the secondary side of the heat exchanger, It can also be used as a heat source for heating the outside air so that the outside air can be heat-insulated and humidified up to the 11 ° C. dew point required by a semiconductor manufacturing plant or the like by humidifying the outside air with an outside air conditioner in winter.

  As shown in FIGS. 2 to 5, the cooling water tank 50 is divided into a low temperature water tank 51, a medium temperature water tank 52, and a high temperature water tank 53 by a tank interval wall 54 and a tank interval wall 56. . An opening 55 for allowing cooling water to flow out from the low temperature water tank 51 to the intermediate temperature water tank 52 is provided in the tank interval wall 54 that partitions the low temperature water tank 51 and the intermediate temperature water tank 52. An opening 57 for allowing cooling water to flow out from the high temperature water tank 53 to the intermediate temperature water tank 52 is provided in the tank interval wall 56 that partitions the intermediate temperature water tank 52 and the high temperature water tank 53. Further, a shelf 58 is provided between the tank spacing wall 54 and the tank spacing wall 56 so as to be flush with the lower end portion of the opening 55, and the shelf 59 is flush with the lower end portion of the opening 57. Provided. The two shelves 58 and 59 are provided so as to cross the upper part of the medium-temperature water tank 52, and serve as running paths for cooling water flowing out from the openings 55 and 57. The two shelves 58 and 59 are provided with weirs 60 and 61 at their tip portions. The weir 60 forms a waterfall that drops cooling water from the low-temperature water tank 51 to the intermediate-temperature water tank 52 using the difference in water level between the low-temperature water tank 51 and the intermediate-temperature water tank 52. The weir 61 forms a waterfall that drops cooling water from the high-temperature water tank 53 to the intermediate-temperature water tank 52 using the difference in water level between the high-temperature water tank 53 and the intermediate-temperature water tank 52. Here, the waterfall drop ΔH between the weir 60 and the weir 61, the difference Δh between the lower end of the weir 60 and the upper end of the weir 61, the interval ΔW between the weir 60 and the weir 61, the upper end of the weir 61 and the liquid level of the medium hot water tank 52 The height ΔHa and the depth ΔD of the cooling water in the intermediate temperature water tank 52 are combined and mixed by a waterfall-shaped falling flow, and the inrush with the velocity into the accumulated water due to the potential energy of the falling water mass Necessary conditions are provided to efficiently cause agitation and mixing caused by convection and bubbles generated by waterfall. For example, it is desirable to satisfy the following conditions. The waterfall drop ΔH between the weir 60 and the weir 61 is about 0.5 m, the difference Δh between the lower end of the weir 60 and the upper end of the weir 61 is about 0.1 to 0.2 m, and the distance ΔW between the weir 60 and the weir 61 is 0. The height ΔHa between the upper end of the weir 61 and the liquid surface of the intermediate temperature water tank 52 is about 0.5 to 1.0 m, and the depth ΔD of the cooling water in the intermediate temperature water tank 52 is about 1 to 0.2 m. It is set to about 0 to 1.5 m. These values are determined according to various conditions in the system.

The low-temperature water tank 51, the medium-temperature water tank 52, and the high-temperature water tank 53 of the cooling water tank 50 are not intended for heat storage, but are associated with changes in the operating conditions of the system due to fluctuations in outside air conditions and load fluctuations. In order to suppress the variation in the water temperature in each tank, it varies somewhat depending on the overall length of the system, but it is about several minutes (2 to 3 minutes) of the circulating water amount at maximum load.
The low-temperature water tank 51 is cooled by cooling towers 31, 33, 35 (cooling tower pumps 32, 34, 36 flow at the rated water amount at the maximum load in summer, and cool if the cooling tower inlet temperature is 37 ° C. The cooling water is cooled to a tower outlet temperature of 32 ° C. In winter, the total flow rate of the cooling tower pump is reduced and the outside air temperature is lowered. For example, if the cooling tower inlet temperature is 37 ° C, the cooling tower outlet temperature is reduced. Cooling water cooled to 27 ° C.) and water in the low-temperature water tank is mixed, so it is averaged to a low temperature as low-temperature cooling water, and between the tanks with the medium-temperature water tank 52 The cooling water cooled to the intermediate temperature water tank 52 is sent to the waterfall tank 52 using waterfall difference between the two tanks through the opening 55 provided in the partition wall 54. In part of the summer and intermediate periods, the cooling water temperature in the low temperature water tank 51 is managed in the operating state of the cooling towers 31, 33, and 35. Further, in the winter season or the like, it is also a cooling water receiving water tank that is used as a heating source that has passed through the heat exchanger circuits 40a and 40b from the high-temperature water water tank 53 to be cooled and returned. In this case, the temperature and flow rate of the return water from the heat exchanger circuits 40 a and 40 b are also used as a management signal for the cooling water temperature in the low temperature water tank 51.

The medium-temperature water tank 52 is a cooling water supply tank that is usually adjusted by the low-temperature water tank 51 to the refrigerators 21, 23, 25. In the winter and intermediate periods, the low-temperature water tank 51 has an opening 55. It has a function of stirring and mixing waterfall-like low-temperature cooling water that falls and flows in and waterfall-like high-temperature cooling water that falls and flows from the high-temperature water tank 53 through the weir 61 and a temperature adjustment function.
The low-temperature cooling water that falls from the opening 55 via the shelf 58 and the weir 60 and the high-temperature cooling water that falls from the opening 57 via the shelf 59 and the weir 61 are generated on the refrigerator side. The cooling water amount is operated while maintaining the temperature difference at the inlet / outlet of the condenser of the refrigerator at 5 ° C., whereas the water temperature difference at the inlet / outlet of the cooling towers 31, 33, and 35 is the cooling tower due to a decrease in the outside air temperature. This is caused by a reduction in cooling load due to an increase in capacity and a decrease in outside air temperature, and a flow rate that is less than half the rated ratio of the cooling tower pumps 32, 34, and 36 due to, for example, a 10 ° C difference instead of a 5 ° C difference in rating. It is. The cooling water flowing through the condensers of the refrigerators 21, 23, 25 has a temperature difference of 5 ° C. even if it is smaller than the rating due to the reduction of the cooling load. If the total flow rate of the refrigerator circuits 20 a +20 b + 20 c at this time is 1, If the inlet / outlet water temperature difference of the towers 31, 33, 35 is 10 ° C. and the flow rates of the heat exchanger circuits 40a, 40b are zero, the total flow rate of the cooling tower circuits 30a + 30b + 30c is 0.5. Therefore, when the refrigerant circuit 20a, 20b, 20c is pumped from the intermediate temperature water tank 52 at a flow rate of 1 and transferred to the high temperature water tank 53, the cooling tower circuits 30a, 30b, 30c start from the high temperature water tank 53. It will be transferred to the low temperature water tank 51 at a flow rate of 0.5, and the remaining 0.5 will be surplus in the high temperature water tank 53 and poured down from the opening 57 to the medium temperature water tank 52 through the shelf 59 and the weir 61. It becomes. The medium-temperature water tank 52 is supplied with 0.5-minute flow of cooling water conveyed from the low-temperature water tank through the cooling tower circuits 30a, 30b, and 30c through the shelf 58 and the weir 6051. Is done.
The high-temperature water tank 53 receives the high-temperature cooling water in which the exhaust heat from the refrigerant in the refrigeration cycle by the condensers of the refrigerators 21, 23, 25 is heat-exchanged, and the cooling tower pumps of the cooling tower circuits 30 a, 30 b, 30 c Refrigerator exhaust heat pumped up by the circulation pumps 42 and 44 of the heat exchanger circuits 40a and 40b is used as a supply source of high-temperature cooling water pumped up by the pumps 32, 34 and 36 and sent to the cooling towers 31, 33 and 35. The high-temperature cooling water to be carried becomes a supply source for supplying water to the heating load as a heat source. Furthermore, the capacity of the cooling towers 31, 33, and 35 increases with a decrease in the outside air temperature in the intermediate period and winter, and a large cooling water temperature difference occurs, so that the number of operating cooling towers 31, 33, and 35 is larger than the number of operating refrigerators. When the water temperature is reduced, the water is dropped into a waterfall using the water level difference between the two tanks from the opening 57 provided in the tank interval wall 56 between the water tank 52 and the warm water tank 52. To control the water temperature of the medium temperature water tank 52 and to secure the amount of water supplied to the refrigerators 21, 23, 25.

  And the opening 55 provided in the tank space | interval wall 54 which divides the low temperature water tank 51 and the intermediate temperature water tank 52 is provided with the opening 57 provided in the tank space wall 56 which partitions the high temperature water tank 53 and the intermediate temperature water tank 52. It is formed to be located at a higher place. Thus, the low-temperature water tank 51, the medium-temperature water tank 52, and the high-temperature water tank 53 can always hold the water level so that the low-temperature water tank 51 becomes high, and the operation of the refrigerator group and the cooling tower group In addition, the intermediate temperature water tank 52 can be held such that the water level is always lower than that of the high temperature water tank 53. Therefore, the flow direction can always be determined from the low temperature water tank 51 to the medium temperature water tank 52 and from the high temperature water tank 53 to the medium temperature water tank 52, and the flow direction is changed inadvertently. Unexpected water temperature mixing can be avoided. Therefore, the functional purpose of each tank is clarified.

The openings 55 and 57 and the weirs 60 and 61 and the waterfall will be described. By providing the openings 55 and 57 and the weirs 60 and 61, the low-temperature water tank 51, the medium-temperature water tank 52, and the high-temperature water tank 53 each maintain a predetermined water level to generate waterfall-like waterfall. Rapid mixing of the two parties (water and water in the medium-temperature water tank 52) or the three parties (low-temperature water, high-temperature water, and water in the medium-temperature water tank 52) by the stirring action caused by the rising of bubbles generated simultaneously with the collision stirring In addition, it is possible to reduce the temperature difference inside the intermediate temperature water tank 52.
The refrigerators 21, 23, and 25 are respectively connected to the inlet and outlet of the evaporator of the refrigerator so that cold water can be supplied to the cold water coil of the air conditioner as in the conventional device shown in FIG. And a pipe line connecting the return header.

Next, the operation of the refrigerator system 10 according to the present embodiment configured as described above will be described.
FIG. 6 shows a normal operation at a cooling peak load in summer.
In the refrigerator system of FIG. 1 and FIG. 6 without a spare machine, the three refrigerators 21, 23, 25 and the three cooling towers 31, 33, 35 are all fully operated, and the three refrigerator circuits 20a. , 20b, 20c and the three cooling tower circuits 30a, 30b, 30c, the cooling water pumps 22, 24, 26 and the cooling tower pumps 32, 34, 36 are operated at rated flow rates. In FIG. 6, the operated circuit is indicated by a bold line. Thereby, the cooling water pumped up from the intermediate temperature water tank 52 by the cooling water pumps 22, 24, and 26 of the three refrigerator circuits 20a, 20b, and 20c passes through the condensers of the refrigerators 21, 23, and 25, respectively. Heat exchange with the refrigerant in the refrigeration cycle results in a high temperature, which is sent to the high temperature water tank 53. The cooling water pumped up from the high-temperature water tank 53 by the cooling tower pumps 32, 34, and 36 of the three cooling tower circuits 30a, 30b, and 30c is cooled by the cooling towers 31, 33, and 35, respectively. 51 is sent out. Here, at the peak load in summer, the wet bulb temperature of the outside air rises to a maximum of about 27 ° C. Therefore, the high-temperature cooling water of 37 ° C. that has been exchanged by the condensers of the refrigerators 21, 23, 25 is removed. The cooling towers 31, 33, and 35 are cooled by introducing them into the cooling tower, but the cooling capacity of the cooling towers 31, 33, and 35 can be cooled only to 32 ° C. even if heat exchange with the outside air is performed. Is 5 ° C. The cooling water at the inlet / outlet of the cooling towers 31, 33, and 35 is approximately equal to the inlet / outlet cooling water temperature difference of 5 ° C. and the absolute values of 32 ° C. and 37 ° C. of the condensers of the refrigerators 21, 23, 25. Therefore, the amount of cooling water pumped by the refrigerator circuits 20a, 20b, and 20c from the medium-temperature water tank 52 is equal to the amount of cooling water pumped by the cooling tower circuits 20a, 20b, and 20c from the high-temperature water tank 53. Therefore, a water flow from the opening 57 of the high-temperature water tank 53 toward the intermediate-temperature water tank 52 does not occur, and the waterfall flows from the opening 55 of the low-temperature water tank 51 toward the intermediate-temperature water tank 52 via the shelf 58 and the weir 60. And fall.
The refrigerators 21, 23, and 25 are capacity-controlled following the load, and the cooling towers 31, 33, and 35 are controlled in number or fan so as to keep the low-temperature water tank 51 at 32 ° C.

FIG. 7 shows normal operation in winter.
Since the outside air becomes a low temperature, the outside air load and the building load decrease, and the outside air of the other party that exchanges heat with the cooling towers 31, 33, 35 becomes low temperature, the capacity of the cooling towers 31, 33, 35 increases. Two refrigerators 21 and 23 and one cooling tower 31 are operated. As a result, the cooling water in the water tank 52 for medium temperature water is pumped up by the cooling water pumps 22 and 24 of the two refrigerator circuits 20a and 20b, and heat is exchanged with the refrigerant of the refrigeration cycle in the condensers of the refrigerators 21 and 23, respectively. It is heated by this and becomes 37 degreeC high temperature cooling water, and is sent out to the water tank 53 for high temperature water. In this case, the amount of cooling water on the refrigerator side is operated while maintaining the temperature difference at the inlet and outlet of the condensers of the refrigerators 21 and 23 at 5 ° C. On the other hand, the water temperature difference at the inlet and outlet of the cooling tower 31 can be 10 ° C. instead of the rated 5 ° C. due to the increase in the cooling tower capacity due to the decrease in the outside air temperature. Can be demonstrated. Therefore, the cooling water in the high temperature water tank 53 is pumped up by the cooling tower pump 32 of one cooling tower circuit 30 a, cooled by the cooling tower 31, and sent to the low temperature water tank 51. The cooling water sent by the cooling tower circuit 30a sent to the low-temperature water tank 51 flows in the direction of the arrow from the opening 55 of the low-temperature water tank 51 using the shelf 58 as a running channel, as shown in FIG. It falls as a waterfall from 60 toward the medium temperature water tank 52. Here, since the cooling tower 31 exhibits a cooling capacity double that of the peak load in summer and the temperature difference of the cooling tower pump 32 can be sent at 10 ° C. instead of 5 ° C., the refrigerator circuit 20a , 20b, the flow rate of one line of the refrigerator circuit that is not pumped into the cooling tower circuit 30a in the cooling water pumped from the medium-temperature water tank 52 to the high-temperature water tank is as shown in FIG. It flows in the direction of the arrow from the opening 57 of the water tank 53 using the shelf 59 as a running water channel, and falls as a waterfall from the weir 61 toward the water tank 52 for medium temperature water. Then, as shown in FIG. 5, cooling water that falls as a waterfall toward the intermediate temperature water tank 52 through the weir 60 and a waterfall from the opening 57 of the high temperature water tank 53 toward the intermediate temperature water tank 52. The cooling water that falls and collides with each other and mixes and falls while falling while colliding with air, collides with the water surface of the intermediate temperature water tank 53 and further mixes, and mixes in the intermediate temperature water tank 53 due to the mixed air. Stir by bubble generation and bubble floating. Then, as shown by the arrow, the intermediate temperature water tank 52 is moved upward.

In the present embodiment, the exhaust heat transferred to the cooling water by heat exchange with the refrigerant of the refrigeration cycle in the condensers of the refrigerators 21 and 23 is transferred to the high temperature water tank 53 by the two heat exchanger circuits 40a and 40b. Cooling water is pumped up by circulating pumps 42 and 44 as a heat source, pure water is used to heat the secondary side of the heat exchanger and used for heating pure water, or outside air is introduced to the secondary side of the heat exchanger and used in winter. It is also used as a heat source for pre-heating of the outside air that can humidify the outside air up to the 11 ° C. dew point required by a semiconductor manufacturing factory etc. by humidifying the outside air with an outside air conditioner.
According to the present embodiment, the cooling capacity of the cooling tower increases with a decrease in the outside air temperature, so that the cooling tower processing heat amount becomes larger than the exhaust heat amount in the condensers of the refrigerators 21, 23, 25. Control of the number of fans or cooling tower pumps 32, 34, and 36 or the number of revolutions of the cooling towers 31, 33, and 35 is performed by the control signal based on the measured temperature 51 (for fan and pump power saving).

  When the operation number control of the cooling tower pumps 32, 34, 36 is performed by the measured temperature control signal of the low temperature water tank 51, the two refrigerators 21, 23 are operated, that is, both the refrigerator circuits 20a, 20b are operated. In some cases, the cooling water pump is operated and only one cooling tower circuit 30a is operated, so that the refrigerator system is established. At this time, when two cooling water pumps 22 and 24 operate and one cooling tower pump 32 works, if the flow rates of the cooling water pumps 22 and 24 and the cooling tower pumps 32, 34 and 36 are the same, Since the amount of cooling water for one cooling tower pump is excessive in the high-temperature water tank 53, water falls and flows from the high-temperature water tank 53 to the intermediate-temperature water tank 52 through the shelf 59 and the weir 61 from the opening 57. In addition, since there is a supply of low-temperature cooling water from the low-temperature water tank 51 through the opening 55 through the shelf 58 and the weir 60, the water in the intermediate-temperature water tank 52 already filled in the intermediate-temperature water tank 52 is cooled to a low temperature. Inflow from the water tank 51 and the high temperature water tank 53 occurs, and it is necessary for these three members to quickly mix and homogenize. If the mixing is not uniform, the temperature of the cooling water pumped to the refrigerator circuits 20a and 20b will fluctuate, which will hinder proper cooling of the cold water by the refrigerators 21 and 23. These mixing and agitation mechanisms are accumulated by the ripples caused by the collision between the cooling water supplied as the falling water from the weirs 60 and 61 and the water stored in the intermediate temperature water tank 52 and the potential energy of the falling water mass. Air bubbles generated in the pooled water in the hot water tank 52 due to air entrainment caused by rushing into the water and convection caused by it, and vortexes generated when the falling water mass flows in and turbulence of the water surface It is used for agitation due to the speed difference from the convection of water due to the water, and is mixed very uniformly.

FIG. 8 shows the normal operation in the intermediate period.
Since the outside air becomes low temperature, the outside air load and the building load decrease, and the outside air of the partner to exchange heat in the cooling tower becomes low temperature, the capacity of the cooling tower increases. For example, three refrigerators 21, 23, 25 And two cooling towers 31 and 33 are operated. As a result, the cooling water in the medium-temperature water tank 52 is pumped up by the cooling water pumps 22, 24, and 26 of the three refrigerator circuits 20a, 20b, and 20C, and the refrigeration cycle of the refrigerators 21, 23, and 25 is respectively performed. It is heated by exchanging heat with the refrigerant and becomes high-temperature cooling water at 37 ° C., and is sent to the high-temperature water tank 53. In this case, the amount of cooling water on the refrigerator side is operated while maintaining the temperature difference at the inlet and outlet of the condensers of the refrigerators 21, 23, 25 at 5 ° C. On the other hand, the water temperature difference between the inlets and outlets of the cooling towers 31 and 33 is not the rated 5 ° C. difference due to the increased capacity of the cooling tower due to a decrease in the outside air temperature. 33 will be able to demonstrate its ability from the peak summer load. Therefore, the cooling water in the high temperature water tank 53 is pumped up by the cooling tower pumps 32 and 34 of the two cooling tower circuits 30 a and 30 b, cooled by the cooling towers 31 and 33, and sent to the low temperature water tank 51. . The cooling water sent by the cooling tower circuits 30 a and 30 b sent to the low-temperature water tank 51 falls from the opening 55 of the low-temperature water tank 51 toward the intermediate-temperature water tank 52 through the shelf 58 and the weir 60. And fall. Here, since the cooling tower 31 exhibits a larger cooling capacity than that at the peak load in summer and the temperature difference of the cooling tower pump 32 can be sent with a large temperature difference instead of 5 ° C., the refrigerator circuit If the cooling water pumps 22 and 24 and the cooling tower pumps 32, 34 and 36 have the same flow rate in the cooling water pumped from the intermediate-temperature water tank 52 to the high-temperature water tank 20a, 20b and 20c, the cooling tower circuit 30a , 30b, 30c, the flow rate for one system of the refrigerator circuit falls as a waterfall from the opening 57 of the hot water tank 53 to the intermediate hot water tank 52 through the shelf 59 and the weir 61. .

During the interim period, the outdoor wet bulb temperature is low, so the capacity of the cooling tower is greater than during summer peak loads. Therefore, the two cooling towers 31 and 33 can be used to cool the exhaust heat exchanged by the condensers of the three refrigerators 21, 23 and 25. In this case, the cooling water inlet / outlet temperature difference between the cooling towers 31 and 33 is larger than 5 ° C., such as 7 ° C. to 9 ° C.
According to the present embodiment, the cooling capacity of the cooling tower increases with a decrease in the outside air temperature, so that the cooling tower processing heat amount becomes larger than the exhaust heat amount in the condensers of the refrigerators 21, 23, 25. Control of the number of fans or cooling tower pumps 32, 34, and 36 or the number of revolutions of the cooling towers 31, 33, and 35 is performed by the control signal based on the measured temperature 51 (for fan and pump power saving).

  When the operation number control of the cooling tower pumps 32, 34, 36 is performed by the measured temperature control signal of the low temperature water tank 51, the three refrigerators 21, 23, 25 are operated, that is, the refrigerator circuit 20a, In some cases, the cooling water pump is operated for both 20b and 20c, and the refrigerator system is established only by operating the two cooling tower circuits 30a and 30b. At this time, when the three cooling water pumps 22, 24, 26 operate and the two cooling tower pumps 32, 34 work, the flow rates of the cooling water pumps 22, 24 and the cooling tower pumps 32, 34, 36 are the same. Then, since the amount of cooling water for one cooling tower pump is excessive in the high temperature water tank 53, the water drops from the high temperature water tank 53 to the medium temperature water tank 52 through the shelf 59 and the weir 61 from the opening 57. Inflow occurs, and there is also a supply of low-temperature cooling water from the low-temperature water tank 51 through the opening 55 through the shelf 58 and the weir 60. Therefore, in the intermediate-temperature water tank 52, the already filled medium-temperature water tank 52 Inflow of water from the low-temperature water tank 51 and the high-temperature water tank 53 occurs in the water, and it is necessary for these three to quickly mix and homogenize. If the mixing is not uniform, the temperature of the cooling water pumped into the refrigerator circuits 20a, 20b, and 20c will fluctuate, which will hinder proper cooling of the cold water by the refrigerators 21, 23, and 25. These mixing and agitation mechanisms are accumulated by the ripples caused by the collision between the cooling water supplied as the falling water from the weirs 60 and 61 and the water stored in the intermediate temperature water tank 52 and the potential energy of the falling water mass. Air bubbles generated in the pooled water in the hot water tank 52 due to air entrainment caused by rushing into the water and convection caused by it, and vortexes generated when the falling water mass flows in and turbulence of the water surface It is used for agitation due to the speed difference from the convection of water due to the water, and is mixed very uniformly.

Next, the case where the exhaust heat exchanged by the condensers of the refrigerators 21, 23, 25 is used (however, the amount of exhaust heat of the refrigerator> the amount of exhaust heat used) will be described.
When using the exhaust heat exchanged by the condensers of the refrigerators 21, 23, 25 in the summer, the intermediate period, and the winter, a part of the heat exhaust to the outside air in the cooling towers 31, 33, 35 is used as the exhaust heat utilization unit That is, since the heat exchanger circuits 40a and 40b are digested, the corresponding cooling towers are stopped, the amount of water in the cooling tower circuits 30a, 30b and 30c is reduced, and the exhaust heat utilization system, that is, the heat exchanger circuits 40a and 40b. However, when the temperature difference of the exhaust heat utilization system is significantly larger than the rated cooling tower inlet / outlet cooling water temperature difference of 5 ° C, the amount of water flowing through the exhaust heat utilization system decreases. Since the amount of cooling water is excessive in the water tank 53, a flow through the opening 57 from the high-temperature water tank 53 to the medium-temperature water tank 52 occurs (the amount of heat is different). At this time, a waterfall-like flow from both the low temperature water tank 51 and the high temperature water tank 53 can be made to the intermediate temperature water tank 52. It is necessary to mix the flow of greatly different water temperatures for a short time in a small space. For this reason, the parabolic line of the falling water by the flow rate of the two cooling tower pumps 32 and 34 falling from the weir 60 intersects the stable water level of the medium temperature water tank 52 and the cooling water pump 22 falling from the weir 61. The tank interval wall 54 and the tank interval wall are arranged so that the parabola of the falling water due to the flow rate of one unit substantially coincides with the point where the water level of the stable medium temperature water tank 52 intersects, or two parabolas intersect in the air. If the distance to 56 is set, falling falling water masses of different temperatures can be mixed well, and mixing and stirring mechanism, that is, cooling water supplied as falling water from the weirs 60 and 61 and the medium temperature water tank 52 Waves caused by collision with accumulated water, rushing into the accumulated water due to potential energy of falling water mass and convection due to it, vortex and water surface turbulence generated when the falling water mass flows in Accompanied by Agitation effect due to the speed difference between the convection of water by bubbles generated in the water which accumulated a medium-temperature water tanks 52 medium by air can maximize.

As described above, when the exhaust heat generated by the refrigeration cycle condenser of the refrigerator is radiated to the atmosphere in the cooling tower, it differs depending on the waterfall falling from the weir provided in the cooling water tank except during summer peak load By mixing the cooling water of the temperature well, the exhaust heat generated in the refrigeration cycle condenser of the refrigerator can be used as a heating heat source while operating according to the load of the refrigerator, or the exhaust heat can be used in the cooling tower. It can be operated by releasing heat to the atmosphere. In addition, if there is a pre-heating heating load for humidifying the outside air in the outdoor air conditioner during the winter or intermediate period, the exhaust heat on the condenser side of the refrigerator is once collected in the high-temperature water tank of the cooling water tank. Therefore, by connecting a load and a high-temperature water tank through a separate circulation path from here and circulating with a pump, this can be used as a heating heat source, and the number of operating boilers and the number of cooling towers can be reduced. In addition, when using the exhaust heat of the by-product generated in the refrigeration cycle condenser of a refrigerator intended for cooling as a heating heat source, if the exhaust heat remaining without partitioning is dissipated to the atmosphere in the cooling tower, the water temperature By interposing a cooling water tank as a buffer that absorbs sudden changes, the heat source from the heat capacity of the refrigerator, cooling tower, cooling coil, heating heat exchanger, heating coil, piping, and the characteristics of the automatic control system that controls them The risk of system disruption can be avoided. Similarly, a cooling water tank as a buffer that absorbs sudden changes in water temperature intervenes to enable switching to maintain the system with high efficiency against fluctuations in load and weather conditions, as well as periodic maintenance and equipment. It is possible to suppress the occurrence of turbulence in the entire cooling water system of the refrigerator system due to switching of operating equipment due to trouble.
Furthermore, according to the present embodiment, the compressor capacity can be reduced with respect to the refrigerators 21, 23, 25 with respect to the high-efficiency operation except during summer peak load, that is, the cooling water temperature being lowered into the condenser. Efficiency, that is, coefficient of performance (COP) = amount of heat taken by the evaporator (kcal) / (electric power required for the compressor (KW) x 860 (kcal / KW)) is improved, and power consumption is reduced. Therefore, the operation of the cooling towers 31, 33, and 35 can be managed so as to lower the cooling water temperature according to the outside air temperature.
Except during summer peak load, when the outdoor wet bulb temperature is low, the cooling water temperature can be set low, and the COP of the refrigerators 21, 23, 25 can be increased.

In the intermediate and winter seasons, the cooling tower capacity increases during periods when the outdoor wet bulb temperature is low, but the refrigerator and cooling tower form a closed circuit with a pipe and are not a fixed pair. Since the cooling tower group can be formed as a separate piping system, the number of fans and cooling tower pumps 32, 34, and 36 provided in the cooling towers 31, 33, and 35, respectively, by a control signal based on the measured temperature of the low-temperature water tank 51. Control or rotational speed control is performed, and if it is unit control, a partial stop is possible.
When troubles occur in the refrigerators 21, 23, 25, the cooling towers 31, 33, 35, pumps, and devices, the flexibility of combinations of the devices increases. In addition, flexibility can be obtained during maintenance.

Refrigerator exhaust heat (refrigerator outlet cooling water) can be used as a heat source, and the power of the cooling tower can be reduced.
The fluctuation of the cooling water temperature at the refrigerator inlet can be reduced, and the refrigerator can be operated stably.
In addition, since the refrigerator and the cooling tower form a closed circuit with a pipe and do not form a fixed pair, the refrigerator group and the cooling tower group can be formed as separate piping systems. Various combinations of cooling tower) method, type, characteristics, etc. are possible, and it is easy to take an appropriate method depending on load conditions, outside air conditions, environmental response (white smoke prevention), etc.

  In the above embodiment, the case where the three refrigerator circuits 20a, 20b, and 20c, the three cooling tower circuits 30a, 30b, and 30c, and the two heat exchanger circuits 40a and 40b are described. The present invention is not limited to this, and it is possible to arbitrarily change the (refrigerator, cooling tower) system, type, characteristics, number, capacity, etc. of each device according to the purpose of use. For example, for a refrigerator, a compression type refrigerator has been described as an example, but naturally, a cooling system that transfers heat to an absorber and a condenser of an absorption refrigerator is also referred to as a “condenser of a refrigerator system”. Needless to say, this is the “cooling water system on the side”.

It is explanatory drawing which shows the refrigerator system which concerns on one Embodiment of this invention. It is a perspective view which shows the cooling water tank used for the refrigerator system of FIG. It is a top view which shows the cooling water tank used for the refrigerator system of FIG. It is sectional drawing which shows the cooling water tank used for the refrigerator system of FIG. It is explanatory drawing which shows the effect | action of the cooling water tank used for the refrigerator system of FIG. It is explanatory drawing which shows the driving | running state of the summer of the refrigerator system of FIG. It is explanatory drawing which shows the driving | running state in the winter of the refrigerator system of FIG. It is explanatory drawing which shows the operation state of the intermediate | middle period of the refrigerator system of FIG. It is explanatory drawing which shows the conventional refrigerator system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Refrigerator system 20a, 20b, 20c Refrigerator circuit 21,23,25 Refrigerator 22,24,26 Cooling water pump 30a, 30b, 30c Cooling tower circuit 31,33,35 Cooling tower 31,33,35 Cooling tower pump 40a, 40b Heat exchanger circuit 41, 43 Heat exchanger 42, 44 Circulating pump 50 Cooling water tank 51 Low temperature water tank 52 Medium temperature water tank 53 High temperature water tank 54, 56 Spacing wall 55, 57 Opening 58, 59 Shelf 60, 61 weir

Claims (4)

In the cooling water system on the condenser side of the refrigerator system,
A refrigerator circuit having a refrigerator and a cooling water pump;
A cooling tower circuit having a cooling tower and a cooling tower pump;
A cooling water tank partitioned into a low temperature water tank, a medium temperature water tank and a high temperature water tank,
The refrigerator circuit is arranged between the medium temperature water tank and the high temperature water tank,
The cooling tower circuit is arranged between the low temperature water tank and the high temperature water tank,
The tank interval wall that partitions the low-temperature water tank and the intermediate-temperature water tank has an opening for dropping cooling water from the low-temperature water tank to the intermediate-temperature water tank,
It flows out from the opening of the low temperature water tank between the tank interval wall that partitions the low temperature water tank and the medium temperature water tank and the tank interval wall that partitions the medium temperature water tank and the high temperature water tank. A weir that provides a shelf for guiding cooling water and forms a waterfall that drops cooling water from the low-temperature water tank to the intermediate-temperature water tank using a difference in water level between the low-temperature water tank and the intermediate-temperature water tank At the tip of the shelf,
The tank interval wall that partitions the intermediate temperature water tank and the high temperature water tank is provided with an opening for dropping cooling water from the high temperature water tank to the intermediate temperature water tank.
It flows out from the opening of the high temperature water tank between the tank interval wall that partitions the low temperature water tank and the intermediate temperature water tank, and the tank interval wall that partitions the intermediate temperature water tank and the high temperature water tank. A weir that provides a shelf for guiding cooling water and forms a waterfall that drops cooling water from the high-temperature water tank to the intermediate-temperature water tank using a difference in water level between the high-temperature water tank and the intermediate-temperature water tank Is provided at the front end of the shelf. The refrigerator system according to claim 1, wherein
The opening provided in the tank interval wall that partitions the low temperature water tank and the intermediate temperature water tank is positioned higher than the opening provided in the tank interval wall that partitions the high temperature water tank and the intermediate temperature water tank. A refrigerator system characterized by that. The refrigerator system according to claim 1 or 2,
Two shelves provided between a tank interval wall that partitions the low temperature water tank and the intermediate temperature water tank, and a tank interval wall that partitions the intermediate temperature water tank and the high temperature water tank, It is provided so that it may become flush with the lower end part of the refrigerator system. The refrigerator system according to any one of claims 1 to 3,
A refrigerator system, wherein a heat exchanger circuit having a heat exchanger and a circulation pump is disposed between the high-temperature water tank and the low-temperature water tank.

Images