Outdoor air treatment air conditioner, and air conditioning system equipped therewith

Abstract

To save energy of an outdoor air conditioner, and to reduce power consumption of the outdoor air conditioner by stably supplying cold / hot water adjusted in temperature by a heat pump chiller to the outdoor air conditioner while keeping the cold / hot water at a predetermined temperature.SOLUTION: An outside air processing air conditioner 2 includes: a flow path switching valve for switching a flow path of hot water supplied from a condenser to a hot water tank 3, to a flow path for cooling the hot water by a second heat exchanger 73 with underground water 6 as a heat source, which circulates between the condenser and the second heat exchanger 73, when the temperature of the hot water tank 3 becomes equal to or higher than a predetermined temperature; and a flow path switching valve for switching a flow path of cold water supplied from an evaporator to a cold water tank 4, to a flow path for increasing the temperature of the cold water by a third heat exchanger 91 with waste heat as a heat source, which circulates between the evaporator and the third heat exchanger 91, when the temperature of the cold water tank 4 becomes equal to or lower than a predetermined temperature.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a heat pump chiller (cooling and heating chiller), an outdoor air-conditioning unit using ground heat or waste heat (unused energy) as a heat source, and an air-conditioning system equipped with the same.

Background Art

[0002] Conventionally, an outdoor air-conditioning unit (hereinafter referred to as an outdoor unit) that uses a heat pump chiller and ground heat as heat sources has been known.

[0003] For example, Patent Document 1 below discloses an air-conditioning system that directly or indirectly uses groundwater pumped from a production well as a heat source water in a heat exchanger (cooling coil, heating coil, heating and cooling coil, etc.) of an air conditioner. By using the heat of groundwater, the power consumption can be kept lower than that of a conventional air-conditioning system.

[0004] In addition, Patent Document 2 below discloses an air-conditioning system that combines an absorption chiller with a heat pump, cools the cooling coil of the outdoor unit by the heat pump, eliminates the need for producing low-temperature chilled water by the absorption chiller, improves the operating efficiency of the absorption chiller, and responds to rapid load fluctuations of the outdoor unit with the heat pump.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0006] The air conditioning system described in Patent Document 1 below achieves energy conservation by utilizing groundwater, which is geothermal energy, as a heat source. On the other hand, large amounts of hot water (unused energy) are discharged from semiconductor manufacturing plants, seafood processing plants, and nursing care facilities, etc. If this unused energy can be used as an air conditioning system (hereinafter also referred to as an air conditioning system), further energy conservation can be achieved.

[0007] Patent Document 2, described below, discloses an air conditioning system that combines an absorption chiller with a heat pump to improve the operating efficiency of the absorption chiller and respond to load fluctuations. However, the technology described in Patent Document 2 requires a heat pump in addition to the absorption chiller, and also requires piping and control equipment to connect them, resulting in a complex and costly system.

[0008] This invention has been made in view of the above-mentioned problems, and aims to provide an air conditioning unit that is robust to fluctuations in outside air load and energy-saving, and an air conditioning system equipped therewith, by utilizing unused energy such as geothermal energy from groundwater and hot water discharged from factories and facilities, and by utilizing the property of water that has a large heat capacity. [Means for solving the problem]

[0009] The present invention provides an outdoor air processing air conditioner comprising: a pre-cooling unit that cools outdoor air to a first outdoor air of a predetermined temperature; a cooling unit that cools the first outdoor air to a second outdoor air of a predetermined temperature; and a heating unit that heats the second outdoor air to a third outdoor air of a predetermined temperature, and supplies the third outdoor air to a building space. The pre-cooling section includes a first radiator-type heat exchanger that cools the first outside air by heat exchange between groundwater supplied from a groundwater supply device and heat-exchanged heat source water. The cooling unit includes a second radiator-type heat exchanger that cools to the second outside air by heat exchange with cooling water from a chilled water tank having a heat storage buffer function, in which chilled water cooled by the evaporator of an indirect heat pump chiller is stored. The heating unit includes a third radiator-type heat exchanger that heats up to the third outside air through heat exchange with hot water from a hot water tank having a heat storage buffer function in which hot water heated by the condenser of the heat pump chiller is stored. When the temperature of the hot water tank exceeds a predetermined temperature, a first flow path switching valve switches the flow path of the hot water supplied from the condenser to the hot water tank to a circulating flow path that circulates between the condenser and the groundwater heat exchanger, which is interposed by a groundwater heat exchanger to which the hot water is cooled by heat exchange with the groundwater in the groundwater heat exchanger. When the temperature of the chilled water tank falls below a predetermined temperature, a second flow path switching valve is provided to switch the flow path of chilled water supplied from the evaporator to the chilled water tank to a flow path that circulates between the evaporator and the exhaust heat exchanger, which is interposed by an exhaust heat heat exchanger to which waste hot water is supplied, and the chilled water is heated in the exhaust heat heat exchanger by heat exchange with the waste hot water. .

[0010] When the temperature of the hot water tank exceeds a predetermined temperature, a first flow path switching valve is provided to switch the flow path of the hot water supplied from the condenser to the hot water tank to a circulating flow path that circulates between the condenser and the groundwater heat exchanger, which is supplied with groundwater and cools the hot water by heat exchange with the groundwater in the groundwater heat exchanger. This prevents the temperature of the hot water tank from rising more than necessary.

[0011] If the temperature of the chilled water tank falls below a predetermined temperature, a second flow path switching valve is provided to switch the flow path of the chilled water supplied from the evaporator to the chilled water tank to a flow path that circulates between the evaporator and the exhaust heat exchanger, which is interposed by an exhaust heat heat exchanger to which waste hot water is supplied, and the chilled water is heated up in the exhaust heat heat exchanger by heat exchange with the waste hot water. This prevents the temperature of the chilled water tank from dropping more than necessary.

[0012] The air conditioning system of the present invention is An outdoor air processing air conditioner comprising: a radiator-type precooling unit equipped with a first radiator-type heat exchanger that uses groundwater to cool outside air to a first outside air at a predetermined temperature; a radiator-type cooling unit equipped with a second radiator-type exchanger that cools the first outside air to a second outside air at a predetermined temperature; and a radiator-type heating unit equipped with a third radiator-type exchanger that raises the temperature of the second outside air to a third outside air at a predetermined temperature; A chilled water tank having a heat storage buffer function that supplies chilled water, which is the heat source water, to the second radiator-type heat exchanger, A hot water tank having a heat storage buffer function that supplies hot water, which is the heat source water, to the third radiator-type heat exchanger, The system includes an indirect heat pump chiller that supplies chilled water to the chilled water tank and hot water to the hot water tank, When the temperature of the hot water tank exceeds a predetermined temperature, a first flow path switching valve switches the flow path of the hot water supplied from the condenser of the heat pump chiller to the hot water tank to a circulating flow path that circulates between the condenser and the groundwater heat exchanger, which is interposed by a groundwater heat exchanger to which the hot water is cooled by heat exchange with the groundwater in the groundwater heat exchanger. When the temperature of the chilled water tank falls below a predetermined temperature, the chilled water flow path supplied from the evaporator of the heat pump chiller to the chilled water tank is switched to a flow path that circulates between the evaporator and the exhaust heat exchanger, which is interposed by an exhaust heat exchanger to which waste heat water, using waste heat as a heat source, is supplied, and the chilled water is heated in the exhaust heat exchanger by heat exchange with the waste heat water. A second flow path switching valve is also provided to switch the flow path of the chilled water supplied from the evaporator of the heat pump chiller to the chilled water tank to a flow path that circulates between the evaporator and the exhaust heat exchanger. [Effects of the Invention]

[0013] According to the outdoor air processing air conditioner of the present invention, the power consumption of the outdoor air handling unit is reduced by a pre-cooling section that processes the outside air into a first outside air using a first heat exchanger that uses groundwater as a heat source. Furthermore, a chilled water tank is provided to store chilled water cooled by the evaporator of the heat pump chiller, and a hot water tank is provided to store hot water heated by the condenser of the heat pump chiller, so that a large amount of heat is stored in the chilled water tank and the hot water tank. As a result, even if the temperature of the chilled and hot water fluctuates due to load fluctuations of the heat pump chiller, the temperature of the chilled and hot water stored in each tank does not fluctuate rapidly. Therefore, complex control is unnecessary, and chilled and hot water can be supplied stably to the outdoor air handling unit.

[0014] Furthermore, when the temperature of the hot water tank reaches or exceeds a predetermined temperature, the flow path of the hot water supplied from the condenser to the hot water tank is cooled by a ground heat exchanger using groundwater as a heat source and then returned to the condenser. Also, when the temperature of the cold water tank drops below a predetermined temperature, the flow path of the cold water supplied from the evaporator to the cold water tank is heated by a waste heat exchanger using waste heat as a heat source and then returned to the evaporator. By doing so, cold and hot water can be stably supplied from the cold and hot water tank to the outdoor unit, and energy conservation can be achieved by utilizing geothermal heat and unused energy.

Brief Description of the Drawings

[0015] [Figure 1] It is a diagram showing the heat exchange flow of the air conditioning system according to an embodiment of the present invention. [Figure 2] It is a diagram showing the air conditioning system according to the first embodiment of the present invention. [Figure 3] It is a diagram showing the air conditioning system according to the second embodiment of the present invention. [Figure 4] It is a diagram showing the air conditioning system according to the third embodiment of the present invention. [Figure 5] It is a diagram showing the power reduction effect for each usage period of a facility equipped with the air conditioning system according to an embodiment of the present invention. [Figure 6] It is a diagram showing the result of estimating the power reduction effect of a facility equipped with the air conditioning system according to an embodiment of the present invention.

Modes for Carrying Out the Invention

[0016] (First Embodiment) Hereinafter, referring to FIGS. 1 to 6, an air conditioning system 10 according to an embodiment of the present invention and an outdoor unit 2 included in the air conditioning system 10 will be described. The air conditioning system 10 includes a heat pump chiller 1 serving as a heat source facility, a hot water tank 3 that is a heat storage tank connected to it by piping, a cold water tank 4, and an outdoor unit 2 connected to these tanks by piping.

[0017] The hot water tank 3 and the chilled water tank 4 store chilled and hot water that have been conditioned by the heat pump chiller 1, thereby accumulating a large amount of heat with minimal temperature fluctuations. In addition, the chilled and hot water stored in the hot water tank 3 and the chilled water tank 4 are subjected to heat exchange by heat exchangers 73 and 91, which use waste heat discharged from factories, etc., or groundwater as a heat transfer medium (heat source water).

[0018] In the air conditioning system 10, the hot water tank 3 and the chilled water tank 4 function as buffers to absorb temperature changes due to load fluctuations, and stably supply hot and chilled water to the air handling unit 2. The air handling unit 2 uses the hot and chilled water from the hot water tank 3 and the chilled water tank 4 as heat source water, and also utilizes groundwater 6 as a heat source water to achieve energy savings. In addition, the hot water stored in the hot water tank 3 is supplied as a heat source water for boilers and underfloor heating, for example, and the chilled water stored in the chilled water tank 4 is supplied as a heat source water for processing rooms (workrooms) for fresh food and for floor cooling, for example.

[0019] In Figure 1, the hot water stored in the hot water tank 3 is supplied to the air handling unit 2 at a temperature of 30°C, which can be controlled, for example, by installing a flow control valve in the piping route connecting the hot water tank 3 and the air handling unit 2. In this embodiment, the temperature of the hot water stored in the hot water tank 3 is 50°C, and the temperature of the chilled water stored in the chilled water tank 4 is 5°C. However, in order to optimize the air conditioning system 10 as a whole, the temperature of the hot water may be higher or lower than 50°C, and the temperature of the chilled water may be lower or higher than 5°C.

[0020] A first embodiment of the present invention will be described using the air conditioning system 10 shown in Figure 2. The heat pump chiller 1 has heat exchangers (not shown) on both the evaporator side and the condenser side. The heat exchanger on the evaporator side produces chilled water by heat exchange between the refrigerant and water. The heat exchanger on the condenser side produces hot water by heat exchange between the refrigerant and water.

[0021] The heat pump chiller 1 is further connected to the seventh and eighth pipes 40 and 50, which are supply lines for chilled water, as well as the ninth and 22nd pipes 51 and 43, which are return lines for chilled water from the air handling unit 2. These supply and return lines form a pipeline through which chilled water circulates between the heat pump chiller 1 and the cooling section 12 of the air handling unit 2.

[0022] The heat pump chiller 1 is provided with a third pipe 20 and a fifth pipe 30, which are hot water supply pipes, and a sixth pipe 32 and a fourth pipe 23, which are hot water return pipes from the outdoor air handling unit 2. These supply and return pipes form a pipeline through which hot water circulates between the heat pump chiller 1 and the heating unit 13.

[0023] The air handling unit 2 uses chilled and hot water supplied from the heat pump chiller 1 as a heat source to adjust the temperature and humidity of the outside air before supplying it to the work area and other areas. As shown in Figure 1, in the factory that is the target of the air conditioning system 10 of this embodiment, the chilled and hot water conditioned by the heat pump chiller 1 is used not only by the air handling unit 2 but also by multiple devices such as boilers, floor heating, and floor cooling.

[0024] The air handling unit 2 is equipped with a filter 9 that captures dust and purifies the outside air 17, a pre-cooling section 11 that utilizes the heat of groundwater, a cooling section 12 to which chilled water cooled by the heat pump chiller 1 is supplied, a heating section 13 to which hot water heated by the heat pump chiller 1 is supplied, and a fan 14 for blowing air.

[0025] The pre-cooling section 11, the cooling section 12, and the heating section 13 are each provided with a heat exchanger (not shown). In the air conditioning system 10 of this embodiment, a radiator is used as the heat exchanger. Because a radiator has a large heat transfer surface area, it enables highly efficient heat exchange. In this embodiment, water is used as the heat transfer medium for the radiator. Water has a high specific heat and high thermal conductivity, and by using a radiator, highly efficient heat exchange can be performed.

[0026] The cooling section 12 is connected to an eighth pipe 50 extending from a chilled water tank 4. The heating section 13 is connected to a fifth pipe 30 extending from a hot water tank 3. The eighth pipe 50 supplies chilled water from the chilled water tank 4, cooled by the heat pump chiller 1, to the cooling section 12. Heat exchange using chilled water takes place in a radiator (not shown) located inside the cooling section 12. The fifth pipe 30 supplies hot water from the hot water tank 3, heated by the heat pump chiller 1, to the heating section 13. Heat exchange using hot water takes place in a radiator (not shown) located inside the heating section 13.

[0027] The air handling unit 2 of this embodiment 1 is equipped with a well 5, a 15th pipeline 70 extending from the well 5, a first heat exchanger 71 utilizing groundwater 6 supplied from the well 5, a 16th pipeline 72, a second heat exchanger 73 utilizing groundwater 6, and a 17th pipeline 74.

[0028] Well 5 provides a stable supply of groundwater 6 at approximately 15°C throughout the year. The groundwater 6 is drained through the 15th pipeline 70, the 16th pipeline 72, and then through the 17th pipeline 74. The groundwater 6 is used as heat source water in the first heat exchanger 71 and the second heat exchanger 73, which are located along the above pathways. Between the first heat exchanger 71 and the precooling section 11, there are the first pipeline 15 and the second pipeline 16. The first pipeline 15 and the second pipeline 16 form a pipeline that circulates between the first heat exchanger 71 and the precooling section 11. The heat source water flowing through the pipeline is cooled in the first heat exchanger 71 and cools the outside air 17 in the precooling section 11. In this way, heat exchange using the heat of the groundwater is performed in the precooling section 11.

[0029] The outside air 17 is cooled in the pre-cooling section 11 by heat exchange using groundwater 6 to become the first outside air 17a (see Figure 5). In the cooling section 12, which is downstream of the pre-cooling section 11, it is further cooled and dehumidified by heat exchange with chilled water from the heat pump chiller 1 to become the second outside air 17b. After that, it is heated and temperature-controlled in the heating section 13 to become the third outside air 17c, which is supplied to the workroom.

[0030] Between the supply line connecting the heat pump chiller 1 and the cooling unit 12, a chilled water tank 4 is provided to store chilled water cooled by the evaporator of the heat pump chiller 1. The seventh pipeline 40, which is a chilled water supply line, is connected to the chilled water tank 4, and chilled water cooled by the evaporator of the heat pump chiller 1 is stored in it. The capacity of the chilled water tank 4 is appropriately determined according to the capacity of the heat pump chiller 1. By setting the capacity of the chilled water tank 4 to be large in proportion to the output of the heat pump chiller 1, a large amount of heat can be stored in the tank.

[0031] A first chilled water tank-side flow path switching valve 41 is provided between the seventh pipe 40, which is the chilled water supply pipeline, and the chilled water tank 4. The first chilled water tank-side flow path switching valve 41 acts as a switching valve to direct the chilled water supplied from the heat pump chiller 1 to the chilled water tank 4 or to the 18th pipe 80. A second chilled water tank-side flow path switching valve 42 is provided between the chilled water tank 4 and the 22nd pipe 43, which is the chilled water return pipeline. The second chilled water tank-side flow path switching valve 42 acts as a switching valve to direct the chilled water supplied from the chilled water tank 4 back to the heat pump chiller 1 or to the 19th pipe 81. The first chilled water tank-side flow path switching valve 41 and the second chilled water tank-side flow path switching valve 42 form a pipeline through which chilled water circulates between the heat pump chiller 1, the chilled water tank 4, and the cooling unit 12.

[0032] Between the heat pump chiller 1 and the heating unit 13, a hot water tank 3 is provided to store the hot water heated by the condenser of the heat pump chiller 1. A third pipe 20, which is a hot water supply pipe, is connected to the hot water tank 3, and the hot water heated by the condenser of the heat pump chiller 1 is stored in the hot water tank 3. The capacity of the hot water tank 3 is determined appropriately according to the capacity of the heat pump chiller 1. By increasing the capacity of the hot water tank 3, the amount of heat stored in the tank can be increased.

[0033] A first hot water tank side flow path switching valve 21 is provided between the third pipe 20, which is a hot water supply pipeline, and the hot water tank 3. The first hot water tank side flow path switching valve 21 acts as a switching valve that directs the hot water supplied from the heat pump chiller 1 either to the hot water tank 3 or to the tenth pipe 60.

[0034] A second hot water tank-side flow path switching valve 22 is provided between the hot water tank 3 and the fourth pipe 23, which is the return pipe for the hot water. The second hot water tank-side flow path switching valve 22 acts as a switching valve that determines whether the hot water supplied from the hot water tank 3 is returned to the heat pump chiller 1 or directed to the 14th pipe 66. The first hot water tank side flow path switching valve 21 and the second hot water tank side flow path switching valve 22 form a pipeline through which hot water circulates between the heat pump chiller 1 and the heating unit 13.

[0035] Next, the operation of this embodiment will be explained with reference to Figure 2. When a pump (not shown) installed in the well 5 is operated, groundwater 6 flows sequentially from the 15th pipeline 70 to the first heat exchanger 71, the 16th pipeline 72, the second heat exchanger 73, and the 17th pipeline 74. Between the precooling section 11 and the first heat exchanger 71, a circulating pipeline is formed by the first pipeline 15 and the second pipeline 16. When a pump (not shown) installed in the precooling section 11 is operated, the heat source water circulates within the above-mentioned circulating pipeline. The heat source water is cooled (heat is released) in the first heat exchanger 71, lowering the temperature of the outside air 17 passing through the precooling section 11. For example, in the summer, as shown in Figure 5(a), outside air 17 with a dry-bulb temperature of 35°C and a relative humidity of 60% is adjusted to a first outside air 17a with a dry-bulb temperature of 17°C and a relative humidity of 100% by passing through the pre-cooling section 11.

[0036] When the heat pump chiller 1 is in operation, chilled water cooled by the evaporator of the heat pump chiller 1 is supplied to the chilled water tank 4 via the seventh pipe 40, which is the chilled water supply pipe. A circulating pipeline is formed between the heat pump chiller 1 and the chilled water tank 4 by the seventh pipe 40, the first chilled water tank side flow path switching valve 41, the second chilled water tank side flow path switching valve 42, and the 22nd pipe 43. As a result, the water in the chilled water tank 4 is cooled. At the same time, hot water heated by the condenser of the heat pump chiller 1 is supplied to the third pipe 20, which is the hot water supply pipe. A circulating pipeline is formed between the heat pump chiller 1 and the hot water tank 3 by the third pipe 20, the first hot water tank side flow path switching valve 21, the second hot water tank side flow path switching valve 22, and the fourth pipe 23. As a result, the water in the hot water tank 3 is heated. In this way, the heat pump chiller 1 simultaneously cools the chilled water tank 4 and raises the temperature of the hot water tank 3.

[0037] A circulating pipeline is formed between the chilled water tank 4 and the cooling unit 12 via the eighth pipeline 50 and the ninth pipeline 51. Therefore, when a pump (not shown) installed in the cooling unit 12 operates, heat exchange takes place between the chilled water tank 4 and the cooling unit 12. Now, let's explain the heat exchange. Chilled water supplied from the heat pump chiller 1 is stored inside the chilled water tank 4 via the seventh pipeline 40 and returned to the heat pump chiller 1 via the 22nd pipeline 43. On the other hand, chilled water returned from the cooling unit 12 is stored inside the chilled water tank 4 via the ninth pipeline 51 and supplied to the cooling unit 12 via the eighth pipeline 50. In other words, the heat exchange referred to here means that the chilled water supplied from the heat pump chiller 1 and the chilled water returned from the cooling unit 12 mix inside the chilled water tank 4. Alternatively, a heat exchanger may be installed inside the chilled water tank 4 without mixing the chilled water. The chilled water cooled by the chilled water tank 4 is supplied to the cooling unit 12, where it exchanges heat with the first outside air 17a to lower the temperature of the outside air 17. For example, in summer, as shown in Figure 5(a), the first outside air 17a with a dry-bulb temperature of 17°C and a relative humidity of 100% is adjusted by the cooling unit 12 to the second outside air 17b with a dry-bulb temperature of 7°C and a relative humidity of 95%.

[0038] A circulating pipeline is formed between the hot water tank 3 and the heating unit 13 via the fifth pipeline 30 and the sixth pipeline 32. Therefore, when a pump (not shown) installed in the heating unit 13 operates, hot water circulates between the hot water tank 3 and the heating unit 13. To explain the heat exchange in the hot water tank, the hot water supplied from the heat pump chiller 1 is stored inside the hot water tank 3 via the third pipeline 20 and returned to the heat pump chiller 1 via the fourth pipeline 23. On the other hand, the hot water returned from the heating unit 13 is stored inside the hot water tank 3 via the sixth pipeline 32 and supplied to the heating unit 13 via the fifth pipeline 30. In other words, heat exchange here refers to the mixing of the hot water supplied from the heat pump chiller 1 and the hot water returned from the heating unit 13 inside the hot water tank 3. Alternatively, a heat exchanger may be installed inside the hot water tank 3 without mixing the hot water. The hot water heated by the hot water tank 3 exchanges heat with the outside air 17 in the heating unit 13, thereby lowering the temperature of the second outside air 17b. For example, in summer, as shown in Figure 5(a), the second outside air 17b, with a dry-bulb temperature of 7°C and a relative humidity of 95%, is adjusted by the heating unit 13 to a third outside air 17c with a dry-bulb temperature of 15°C and a relative humidity of 56%, and supplied to the workroom. The 50°C hot water in the hot water tank 3 is then supplied to the heating unit 13 at 30°C by the flow rate being restricted by the third hot water tank side flow path switching valve 31.

[0039] The following embodiments differ from the air handling unit 2 according to the first embodiment in the respects described below, but otherwise have the same configuration as the air handling unit 2 according to the first embodiment. Therefore, the same reference numerals are used for the same components, and detailed explanations are omitted.

[0040] (Second Embodiment) A second embodiment of the present invention, the summer air conditioning system 10A shown in Figure 3, will be described. As shown in Figure 3, the summer air conditioning system 10A has a first hot water tank side flow path switching valve 21 between the heat pump chiller 1 and the second heat exchanger 73 (also called the groundwater heat exchanger 73) that switches the third pipeline 20, which is the hot water supply pipeline to the hot water tank 3, to the second heat exchanger 73.

[0041] The hot water from chiller 1 is cooled by a second heat exchanger 73 that exchanges heat with groundwater 6, via a first hot water tank side flow switching valve 21, which connects the third pipe 20 to the tenth pipe 60, and the first heat exchanger side flow switching valve 61. The hot water cooled by groundwater then returns to chiller 1 via a thirteenth pipe 64, a second heat exchanger side flow switching valve 65, a fourteenth pipe 66, and a second hot water tank side flow switching valve 22, which connects to the fourth pipe 23.

[0042] Specifically, the first hot water tank-side flow path switching valve 21 and the second hot water tank-side flow path switching valve 22, as well as the first heat exchanger-side flow path switching valve 61 and the second heat exchanger-side flow path switching valve 65, separate the hot water supply pipeline from the hot water tank 3 and form a pipeline that circulates between it and the second heat exchanger 73.

[0043] In the summer, the increased demand for heat exchange in the cooling section 12 leads to a greater volume of chilled water being cooled by the heat pump chiller 1. Consequently, the temperature of the hot water in the hot water tank 3 rises, and the temperature of the hot water in the hot water tank 3 may exceed the target temperature. However, by switching the hot water supply pipeline to a pipeline that circulates between the hot water tank 3 and the second heat exchanger 73, the hot water flowing through the pipeline exchanges heat with the groundwater 6 in the second heat exchanger 73, causing the temperature of the hot water to decrease. At this time, the supply of hot water from the heat pump chiller 1 to the hot water tank 3 is stopped. However, as mentioned above, the hot water tank 3 stores hot water that has been heated in advance by the heat pump chiller 1, so even if hot water is not supplied from the chiller 1, the temperature fluctuation is minimal, and hot water at a predetermined temperature can be stably supplied to the heating section 13.

[0044] Furthermore, by controlling the switching valve, the second heat exchanger 73 can also lower the temperature of the chilled water tank 4 to the temperature of the groundwater 6 in the summer by forming a pipeline through which chilled water circulates between it and the chilled water tank 4. The pipeline through which chilled water circulates between the second heat exchanger 73 and the chilled water tank 4 can be formed by the first chilled water tank side flow path switching valve 41, the 18th pipeline 80, the first heat exchanger side flow path switching valve 61, the 11th pipeline 62, the second heat exchanger 73, the 12th pipeline 63, the 13th pipeline 64, the second heat exchanger side flow path switching valve 65, the 19th pipeline 81, and the second chilled water tank side flow path switching valve 42.

[0045] (Third embodiment) A third embodiment of the present invention, the winter air conditioning system 10B shown in Figure 4, will be described. As shown in Figure 4, the winter air conditioning system 10B is provided with a drain basin 7 in which factory wastewater 8 is stored, a 20th pipeline 90 through which the factory wastewater 8 is supplied from the drain basin 7, and a third heat exchanger 91 through which the factory wastewater 8 is circulated. The 20th pipeline 90 and the 21st pipeline 92 form a pipeline that circulates between the drain basin 7 and the third heat exchanger 91. Factory wastewater 8 at approximately 30°C is stored in the drain basin 7, and heat exchange between the factory wastewater 8 and chilled water takes place in the third heat exchanger 91.

[0046] As shown in Figure 4, the winter air conditioning system 10B is provided with the following between the heat pump chiller 1 and the third heat exchanger 91: a seventh pipe 40 which is a chilled water supply pipe to the chilled water tank 4; a first chilled water tank side flow path switching valve 41 which switches the supply pipe to the third heat exchanger 91; an eighteenth pipe 80; a first heat exchanger side flow path switching valve 61; an eleventh pipe 62; a twelfth pipe 63; a third heat exchanger 91 in which chilled water and factory waste heat exchange heat; a thirteenth pipe 64; a second heat exchanger side flow path switching valve 65; a nineteenth pipe 81; a second chilled water tank side flow path switching valve 42 which switches the chilled water supply pipe to the heat pump chiller 1; and a twenty-second pipe 43. The first heat exchanger-side flow path switching valve 61, the 11th pipeline 62, the 12th pipeline 63, the 13th pipeline 64, and the second heat exchanger-side flow path switching valve 65 are pipelines common to the summer air conditioning system 10A. In summer, hot water is supplied to and used through these common pipelines in the summer air conditioning system 10A. In winter, chilled water is supplied to and used through these common pipelines in the winter air conditioning system 10B.

[0047] The first chilled water tank-side flow path switching valve 41 and the second chilled water tank-side flow path switching valve 42, as well as the first heat exchanger-side flow path switching valve 61 and the second heat exchanger-side flow path switching valve 65, separate the chilled water supply pipeline from the chilled water tank 4 and form a pipeline that circulates between it and the third heat exchanger 91.

[0048] In winter, the increased demand for heat exchange in the heating section 13 leads to a greater heating load in the heat pump chiller 1. In this case, the chilled water tank 4 is also cooled simultaneously, which may cause the temperature of the chilled water supplied to the chilled water tank 4 to fall below the target temperature. However, by switching the chilled water supply pipeline to a pipeline that circulates between the chilled water tank 4 and the third heat exchanger 91, the chilled water flowing through the pipeline exchanges heat with the factory wastewater 8 in the third heat exchanger 91, causing the temperature of the chilled water to rise. At this time, the supply of chilled water from the heat pump chiller 1 to the chilled water tank 3 is stopped. However, as mentioned above, the chilled water tank 4 stores chilled water that has been cooled in advance by the heat pump chiller 1 and has accumulated a large amount of heat, so its temperature does not change much. For this reason, a stable supply of chilled water to the cooling section 12 continues.

[0049] The third heat exchanger 91 (also called the waste heat exchanger 91) can raise the temperature of the hot water tank 3 to the temperature of the factory wastewater 8 in winter by forming a pipeline through which hot water circulates between it and the hot water tank 3. The pipeline through which hot water circulates between the third heat exchanger 91 and the hot water tank 3 can be formed by the first hot water tank side flow path switching valve 21, the tenth pipeline 60, the first heat exchanger side flow path switching valve 61, the eleventh pipeline 62, the twelfth pipeline 63, the third heat exchanger 91, the thirteenth pipeline 64, the fourteenth pipeline 66, and the second hot water tank side flow path switching valve 22.

[0050] As described above, the air handling unit 2 adjusts the temperature and humidity of the outside air 17 by utilizing the heat of the groundwater 6 in the precooling section 11. Since the groundwater 6 is continuously supplied as a heat source at approximately 15°C throughout the year, the power load on the air handling unit 2 can be reduced by utilizing the heat of the groundwater 6 in the precooling section 11.

[0051] Furthermore, the air handling unit 2 utilizes the heat from the factory wastewater 8 in its heating section 13. In the factory that is the target of the air conditioning system 10 of this embodiment, the factory wastewater 8 at approximately 30°C can be used throughout the year, which significantly reduces the power load on the air handling unit 2.

[0052] Furthermore, the air conditioning system 10 can lower the temperature of the chilled water in the chilled water tank 4 to the temperature of the groundwater by passing the chilled water from the chilled water tank 4 through the second heat exchanger 73. In addition, the air conditioning system 10 can raise the temperature of the hot water in the hot water tank 3 by passing the hot water from the hot water tank 3 through the third heat exchanger 91. In this way, energy savings for the air handling unit 2 are achieved by utilizing the heat from the groundwater 6 and the factory wastewater 8.

[0053] The air conditioning system 10 is equipped with a chilled water tank 4 and a hot water tank 3, both of which have a heat storage buffer function, in the supply pipelines for chilled and hot water. Because the chilled and hot water stored in both tanks has a large heat capacity, the temperature of the chilled and hot water supplied to the outdoor air handling unit 2 can be kept constant without complex control.

[0054] Figure 5(a) shows an example of temperature control in the air conditioning system 10 of this embodiment during the summer. For example, in the pre-cooling section 11, the dry-bulb temperature is 35°C, relative humidity is 60%, and the temperature is 4000m 3 When adjusting the outside air 17 at / h to a first outside air 17a with a dry-bulb temperature of 17°C and relative humidity of 100%, conventional methods using only a heat pump chiller consume 48kW of power. In contrast, the air conditioning system 10 uses groundwater 6 at 15°C, resulting in a power consumption of 0kW. The cooling section 12, located downstream of the pre-cooling section 11, consumes 34kW of power, as in conventional methods. In the heating section 13, when adjusting the second outside air 17b with a dry-bulb temperature of 7°C and relative humidity of 95% to a third outside air 17c with a dry-bulb temperature of 15°C and relative humidity of 56%, conventional methods using only a heat pump chiller consume 12kW of power. In contrast, the air conditioning system 10 uses factory wastewater 8 at 30°C, resulting in a power consumption of 0kW.

[0055] As shown in Figure 6, when the power reduction effect of the air conditioning system 10 of this embodiment was confirmed, it was found that the power consumption was reduced from 94 kW in the conventional system to 34 kW by adopting the air conditioning system 10 of this embodiment, resulting in a power reduction effect of 63.8%.

[0056] Figure 5(b) shows an example of temperature control during winter. For example, in the pre-cooling section 11, the dry-bulb temperature is 0°C, relative humidity is 55%, and the temperature is 4000m 3 When adjusting the outside air 17 at / h to a first outside air 17a with a dry-bulb temperature of 11°C and a relative humidity of 26%, conventional methods using only a heat pump chiller consume 14kW of power. In contrast, the air conditioning system 10 uses groundwater 6 at 15°C, resulting in a power consumption of 0kW. In the cooling section 12 downstream of the pre-cooling section 11, power is not consumed in winter, as in conventional systems. In the heating section 13, when adjusting the second outside air 17b with a dry-bulb temperature of 11°C and a relative humidity of 26% to a third outside air 17c with a dry-bulb temperature of 15°C and a relative humidity of 20%, conventional methods using only a heat pump chiller consume 5kW of power. In contrast, the air conditioning system 10 uses factory wastewater 8 at 30°C, resulting in a power consumption of 0kW. As shown in Figure 6, it has been confirmed that the air conditioning system 10 of this embodiment does not consume power in winter.

[0057] Figure 5(c) shows an example of temperature control during spring and autumn. For example, in the pre-cooling section 11, the dry-bulb temperature is 20°C, relative humidity is 50%, and the temperature is 4000m 3 When adjusting the outside air 17 at / h to a first outside air 17a with a dry-bulb temperature of 16°C and relative humidity of 64%, conventional methods using only a heat pump chiller consume 5kW of power. In contrast, the air conditioning system 10 uses groundwater 6 at 15°C, resulting in a power consumption of 0kW. In the cooling section 12 downstream of the pre-cooling section 11, when adjusting the first outside air 17a with a dry-bulb temperature of 16°C and relative humidity of 64% to a second outside air 17b with a dry-bulb temperature of 15°C and relative humidity of 50%, conventional methods using only a heat pump chiller consume 8kW of power. In contrast, the air conditioning system 10 uses groundwater 6 at 15°C, resulting in a power consumption of 0kW. In the heating section 13, as with conventional methods, no power is consumed during the spring and autumn seasons. As shown in Figure 6, it has been confirmed that the air conditioning system 10 of this embodiment does not consume power during the spring and autumn seasons.

[0058] Although one embodiment of the air conditioning system according to the present invention has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the invention. [Explanation of Symbols]

[0059] 1. Heat pump chiller 2 External conditioning machine 3. Hot water tank 4. Cold water tank 5 wells 6 Groundwater 7. Drainage manhole 8. Industrial wastewater 9 filters 10. Air conditioning system 10A Summer Air Conditioning System 10B Winter Air Conditioning System 11. Pre-cooling section 12 Cooling section 13 Heating section 14 Fans 15 1st pipeline 16 2nd pipeline 17 Outside air 17a First outside air 17b Second outside air 17c Third outside air 20 3rd pipeline 21. First hot water tank side flow path switching valve 22. Second hot water tank side flow path switching valve 23 4th pipeline 30 5th pipeline 31. Third hot water tank side flow path switching valve 32 6th pipeline 40 Pipeline 7 41. First chilled water tank side flow path switching valve 42. Second chilled water tank side flow path switching valve 43 22nd pipeline 50 Pipeline 8 51 Pipeline 9 60 Pipeline 10 61 1st heat exchanger side flow path switching valve 62 Pipeline 11 63 Pipeline 12 64 Pipeline No. 13 65. Flow path switching section on the second heat exchanger side. 66 Pipeline 14 70 Pipeline No. 15 71. First heat exchanger 72 Pipeline 16 73. Second heat exchanger (groundwater heat exchanger) 74 Pipeline 17 80 Pipeline 18 81 Pipeline No. 19 90 Pipeline No. 20 91. The third heat exchanger (exhaust heat exchanger) 92 Pipeline 21

Claims

1. An outdoor air processing air conditioner having a pre-cooling unit that cools outside air to a first outside air of a predetermined temperature, a cooling unit that cools the first outside air to a second outside air of a predetermined temperature, and a heating unit that heats the second outside air to a third outside air of a predetermined temperature, and supplying the third outside air to a building space, The pre-cooling section includes a first radiator-type heat exchanger that cools the first outside air by heat exchange between groundwater supplied from a groundwater supply device and heat-exchanged heat source water. The cooling unit includes a second radiator-type heat exchanger that cools to the second outside air by heat exchange with cooling water from a chilled water tank having a heat storage buffer function, in which chilled water cooled by the evaporator of an indirect heat pump chiller is stored. The heating unit includes a third radiator-type heat exchanger that heats up the third outside air by heat exchange with hot water from a hot water tank having a heat storage buffer function in which hot water heated by the condenser of the heat pump chiller is stored. When the temperature of the hot water tank exceeds a predetermined temperature, a first flow path switching valve switches the flow path of the hot water supplied from the condenser to the hot water tank to a circulating flow path that circulates between the condenser and the groundwater heat exchanger, which is interposed by a groundwater heat exchanger to which the hot water is cooled by heat exchange with the groundwater in the groundwater heat exchanger. An outdoor air processing air conditioner characterized by comprising a second flow path switching valve that, when the temperature of the chilled water tank falls below a predetermined temperature, switches the flow path of chilled water supplied from the evaporator to the chilled water tank to a flow path that circulates between the evaporator and the exhaust heat exchanger, which is interposed by an exhaust heat heat exchanger to which waste heat water, using waste heat as a heat source, is supplied, and the chilled water is heated in the exhaust heat heat exchanger by heat exchange with the waste heat water.

2. An outdoor air processing air conditioner comprising: a radiator-type precooling unit equipped with a first radiator-type heat exchanger that uses groundwater to cool outside air to a first outside air of a predetermined temperature; a radiator-type cooling unit equipped with a second radiator-type heat exchanger that cools the first outside air to a second outside air of a predetermined temperature; and a radiator-type heating unit equipped with a third radiator-type heat exchanger that raises the temperature of the second outside air to a third outside air of a predetermined temperature; A chilled water tank having a heat storage buffer function that supplies chilled water, which is the heat source water, to the second radiator-type heat exchanger, A hot water tank having a heat storage buffer function that supplies hot water, which is the heat source water, to the third radiator-type heat exchanger, The system includes an indirect heat pump chiller that supplies chilled water to the chilled water tank and hot water to the hot water tank, When the temperature of the hot water tank exceeds a predetermined temperature, a first flow path switching valve switches the flow path of the hot water supplied from the condenser of the heat pump chiller to the hot water tank to a circulating flow path that circulates between the condenser and the groundwater heat exchanger, through which the groundwater heat exchanger is interposed and the hot water is cooled by heat exchange with the groundwater in the groundwater heat exchanger. An air conditioning system characterized by comprising a second flow path switching valve that, when the temperature of the chilled water tank falls below a predetermined temperature, switches the flow path of chilled water supplied from the evaporator of the heat pump chiller to the chilled water tank to a flow path that circulates between the evaporator and the exhaust heat exchanger, which is interposed by an exhaust heat heat exchanger to which waste heat water, using waste heat as a heat source, is supplied, and the chilled water is heated in the exhaust heat heat exchanger by heat exchange with the waste heat water.

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