Central air conditioning system

Abstract

The utility model relates to the technical field of refrigeration equipment, and discloses a central air conditioning system. The system comprises an air conditioning box used for refrigeration; the air conditioning box comprises a reheating section used for reheating the cooled fresh air entering the air conditioning box. The cooling tower is used for recovering cooling return water in the central air conditioning system through a water return pipe and cooling the cooling return water; an isolating valve is arranged on the water return pipe and is used for controlling the conduction state of cooling return water; the first end of the first branch pipe is connected with the first end of the partition valve, and the second end of the first branch pipe is connected with a water inlet pipe of the reheating section of the air-conditioning box; the first end of the second branch pipe is connected with a water outlet pipe of the reheating section of the air-conditioning box, and the second end of the second branch pipe is connected with the second end of the partition valve and used for guiding water outlet flow of the reheating section of the air-conditioning box into a water return pipe of the cooling tower. According to the system, cooling return water with the high temperature is introduced into the reheating section of the air conditioner box for heat exchange, and the effect of saving energy consumption is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of refrigeration equipment, and particularly relates to a central air conditioning system. Background Art

[0002] An air handling unit is an important part of an air conditioning system, and its main function is to process and condition air to meet specific comfort or industrial process requirements. After fresh air enters the air handling unit, it is first cooled and then passes through a reheating section, where it is heated to a preset temperature by using hot water or steam for heat exchange to meet the usage requirements. A cooling tower uses water as a circulating coolant to absorb heat from the air conditioning system and discharge it into the atmosphere to reduce the water temperature. The warm water generated after the refrigeration equipment in the air conditioning system is cooled enters the cooling tower through a return pipe, and the cooling tower dissipates the heat of the return water and then supplies it to the refrigeration equipment through a supply pipe.

[0003] In summer, the return water temperature of the cooling tower is relatively high, and directly entering the cooling tower for heat dissipation will consume more heat. Therefore, this application provides a central air conditioning system, which introduces the relatively high-temperature return water of the cooling tower into the reheating section of the air handling unit and returns it to the cooling tower after heat exchange, reducing both the heating consumption of the reheating section of the air handling unit and the heat dissipation consumption of the cooling tower, achieving the effect of energy conservation. Summary of the Utility Model

[0004] In view of this, the utility model provides a central air conditioning system to solve the problem of high energy consumption of the cooling tower in summer. The technical solution is as follows:

[0005] A central air conditioning system is provided, and the system includes:

[0006] An air handling unit for refrigeration; the air handling unit includes a reheating section for reheating the fresh air that has been cooled and processed in the air handling unit.

[0007] A cooling tower that recovers the cooling return water in the central air conditioning system through a return pipe and cools the cooling return water; a cut-off valve is provided on the return pipe to control the conduction state of the cooling return water.

[0008] A first branch pipe, with the first end connected to the first end of the cut-off valve and the second end connected to the water inlet pipe of the reheating section of the air handling unit, for introducing the cooling return water into the reheating section of the air handling unit.

[0009] A second branch pipe, with the first end connected to the water outlet pipe of the reheating section of the air handling unit and the second end connected to the second end of the cut-off valve, for introducing the water flow discharged from the reheating section of the air handling unit into the return pipe of the cooling tower.

[0010] In an alternative embodiment, when the partition valve is open, the cooling return water enters the cooling tower through the return pipe; when the partition valve is closed, the cooling return water enters the reheating section of the air handling unit through the first branch pipe at the first end of the partition valve, and the water flow discharged from the reheating section of the air handling unit sequentially enters the cooling tower through the second branch pipe, the second end of the partition valve, and the return pipe.

[0011] In an alternative embodiment, in summer, the partition valve is closed; in spring, autumn, and winter, the partition valve is open.

[0012] In an alternative embodiment, a cooling tower water pump is provided in the cooling tower for pumping the cooling return water into the reheating section of the air handling unit when the partition valve is closed.

[0013] In an alternative embodiment, a branch pipe water pump is provided on the first branch pipe for cooperating with the cooling tower water pump to pump the cooling return water into the reheating section of the air handling unit.

[0014] In an alternative embodiment, a branch pipe valve is provided on the first branch pipe for controlling the conduction state of the first branch pipe.

[0015] In an alternative embodiment, when the partition valve is open and the branch pipe valve is closed, the cooling return water enters the cooling tower through the return pipe; when the partition valve is closed and the branch pipe valve is open, the cooling return water enters the first branch pipe.

[0016] In an alternative embodiment, the air handling unit further includes a fresh air section, a first filtration section, a preheating section, a precooling section, a humidifying section, a rechilling section, a fan section, a second filtration section, and an air outlet section.

[0017] In an alternative embodiment, after fresh air enters the fresh air section of the air handling unit, it is sequentially subjected to filtration treatment in the first filtration section, preheating treatment in the preheating section / precooling treatment in the precooling section, humidifying treatment in the humidifying section, heating treatment in the reheating section / cooling treatment in the rechilling section, filtration treatment in the second filtration section, and then the air is supplied to the room through the air outlet section.

[0018] In an alternative embodiment, the cooling tower also supplies cooling water to the central air conditioning system through a water supply pipe.

[0019] The technical solution provided by the present utility model may include the following beneficial effects:

[0020] The present utility model provides a central air-conditioning system. When the return water temperature of the cooling tower is relatively high, the partition valve is closed, and the cooling return water is introduced into the reheating section of the air handling unit through the first branch pipe, so that the reheating section of the air handling unit can utilize the temperature of the cooling return water to exchange heat with the fresh air that has been cooled by the air handling unit, making the temperature of the cooled fresh air rise to the required temperature, and the temperature of the cooling return water drops after heat dissipation. Since the heat consumed for heating the cooled fresh air is the heat of the cooling return water, the energy for heating in the reheating section is saved, achieving the effect of energy conservation. The cooling return water with a decreased temperature returns to the cooling tower through the second branch pipe. Since the temperature of the cooling return water has dropped, the energy consumed by the cooling tower for cooling the cooling return water is saved, further improving the energy-saving effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the specific embodiments of the present utility model or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0022] Figure 1 It is a schematic structural diagram of a central air-conditioning system according to an embodiment of the present utility model. SPECIFIC EMBODIMENTS

[0023] The following will clearly and completely describe the technical solutions of the present utility model with reference to the drawings. Obviously, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present utility model without creative efforts fall within the protection scope of the present utility model.

[0024] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present utility model. In addition, the terms "first", "second", "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0025] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0026] In addition, the technical features involved in different embodiments of the present utility model described below can be combined with each other as long as they do not conflict with each other.

[0027] An air handling unit is an important part of an air conditioning system, and its main function is to process and condition air to meet specific comfort or industrial process requirements. After fresh air enters the air handling unit, it is first cooled and then passes through a reheating section, where it is heated to a preset temperature by heat exchange using hot water or steam to meet the usage requirements. A cooling tower uses water as a circulating coolant to absorb heat from the air conditioning system and discharge it into the atmosphere to lower the water temperature. The warm water generated after the refrigeration equipment in the air conditioning system refrigerates enters the cooling tower through a return pipe, and the cooling tower dissipates the heat of the return water and then supplies it to the refrigeration equipment through a supply pipe.

[0028] In summer, the return water temperature of the cooling tower is relatively high, and directly entering the cooling tower for heat dissipation will consume more heat. Therefore, the embodiment of the present utility model provides a central air conditioning system, which introduces the cooling tower return water with a relatively high temperature into the reheating section of the air handling unit and returns it to the cooling tower after heat exchange, which not only reduces the heating consumption of the reheating section of the air handling unit but also reduces the heat dissipation consumption of the cooling tower, achieving the effect of energy conservation.

[0029] Figure 1 is a schematic structural diagram of a central air conditioning system according to an embodiment of the present utility model. As Figure 1 shown, in this central air conditioning system, it includes an air handling unit, a cooling tower, a first branch pipe, and a second branch pipe. The air handling unit is used for refrigeration. The air handling unit includes a reheating section for reheating the fresh air that has entered the air handling unit for cooling treatment. The cooling tower recovers the cooling return water in the central air conditioning system through a return pipe and cools the cooling return water. A cut-off valve is provided on the return pipe to control the on-off state of the cooling return water. The first end of the first branch pipe is connected to the first end of the cut-off valve, and the second end of the first branch pipe is connected to the water inlet pipe of the reheating section of the air handling unit. The first branch pipe is used to introduce the cooling return water into the reheating section of the air handling unit. The first end of the second branch pipe is connected to the water outlet pipe of the reheating section of the air handling unit, and the second end of the second branch pipe is connected to the second end of the cut-off valve. The second branch pipe is used to introduce the water flow out of the reheating section of the air handling unit into the return pipe of the cooling tower.

[0030] Figure 1 The working principle of the central air conditioning system shown is as follows:

[0031] Under normal circumstances, for example, when the temperature is relatively low or moderate, the return water temperature of the cooling tower is relatively low. At this time, the isolation valve on the return water pipe is opened, and the cooling return water enters the cooling tower from the return water pipe. When the temperature is relatively high, the return water temperature of the cooling tower is relatively high. At this time, the isolation valve is closed, and the relatively high-temperature cooling return water is introduced into the water inlet pipe of the reheating section of the air handling unit through the first branch pipe, so that the reheating section of the air handling unit can use the temperature of the cooling return water to exchange heat with the fresh air that has been cooled by the air handling unit, so that the temperature of the cooled fresh air rises to the required temperature, and the temperature of the cooling return water drops after heat dissipation. Since the heat consumed to heat the cooled fresh air is the heat of the cooling return water, the energy for reheating the correspondingly cooled fresh air in the reheating section is saved, achieving the effect of energy conservation. The cooling return water with a decreased temperature is discharged through the water outlet pipe of the reheating section of the air handling unit, then returns to the return water pipe of the cooling tower through the second branch pipe, and enters the cooling tower through the return water pipe. Since the temperature of the cooling return water has dropped, the energy consumed by the cooling tower to cool the cooling return water is saved, further improving the energy-saving effect.

[0032] Optionally, a temperature threshold is set. When the temperature reaches the temperature threshold, the isolation valve is closed, and when the temperature is lower than the temperature threshold, the isolation valve is opened. Temperature sensors, thermometers, etc. can also be set to measure the temperature of the cooling return water, and a water temperature threshold is set for the cooling return water. When the water temperature of the cooling return water reaches the water temperature threshold, the isolation valve is closed, and when the water temperature of the cooling return water is lower than the water temperature threshold, the isolation valve is opened. Since the proportion of the time when the temperature of the cooling return water is relatively high in a year is not long, the opening and closing of the isolation valve can be operated by relevant technicians. In order to improve the degree of automation, a device that automatically controls the opening or closing of the isolation valve according to the air temperature or the water temperature of the cooling return water can also be set.

[0033] It should be noted that the water volume and heat of the relatively high-temperature cooling return water may not match the heating demand of the reheating section of the air handling unit. Therefore, in actual application scenarios, the water volume of the introduced cooling return water can be set according to the demand, an isolation valve with a flow control function can be set, or a water valve with a flow control function can be added to control the flow of the cooling return water introduced into the reheating section of the air handling unit, so as to better meet the heating demand of the reheating section and improve the energy-saving effect.

[0034] In an optional implementation manner, when the isolation valve is opened, the cooling return water enters the cooling tower through the return water pipe; when the isolation valve is closed, the cooling return water enters the reheating section of the air handling unit through the first branch pipe at the first end of the isolation valve, and the outlet water flow of the reheating section of the air handling unit sequentially enters the cooling tower through the second branch pipe, the second end of the isolation valve, and the return water pipe.

[0035] In an alternative embodiment, during summer, the partition valve is closed; during spring, autumn and winter, the partition valve is open. That is to say, when the temperature is high in summer, the temperature of the cooling return water is high, and the partition valve is closed to introduce the cooling return water into the reheating section of the air handling unit for heat exchange; during spring, autumn and winter, the temperature of the cooling return water is low, the partition valve is open, and the cooling return water is not introduced into the reheating section of the air handling unit. In addition, since the seasonal distinction is not obvious in some areas, the opening or closing of the partition valve can also be controlled according to the local temperature, selecting the months with higher temperature. Controlling according to seasons or months can reduce the frequency of adjusting the opening or closing of the partition valve, which is more convenient. If further accuracy needs to be increased, the opening or closing of the partition valve can also be controlled according to the temperature or the temperature of the cooling return water. For details, see the foregoing content and will not be elaborated here.

[0036] In an alternative embodiment, a cooling tower water pump is provided in the cooling tower, which is used to pump the cooling return water into the reheating section of the air handling unit when the partition valve is closed. The parameters of the cooling tower water pump are set according to actual needs. For example, when the amount of the cooling return water is large, the rotation speed of the cooling tower water pump is increased, so that more cooling return water participates in the heat exchange in the reheating section of the air handling unit, achieving a better energy-saving effect.

[0037] In an alternative embodiment, a branch pipe water pump is provided on the first branch pipe, which is used to cooperate with the cooling tower water pump to pump the cooling return water into the reheating section of the air handling unit. When the distance between the cooling tower and the air handling unit is far, the first branch pipe and the second branch pipe are long, and the head of the cooling tower water pump may not be able to meet the requirement of pumping the cooling return water into the air handling unit. Therefore, a branch pipe water pump can be added at the first branch pipe to meet the requirement. Further, a branch pipe water pump can also be added at the second branch pipe to cooperate with the cooling tower water pump to pump the cooled return water after heat exchange (i.e., the outlet water flow of the reheating section of the air handling unit) back to the return pipe of the cooling tower.

[0038] In an alternative embodiment, a branch pipe valve is provided on the first branch pipe, which is used to control the conduction state of the first branch pipe. By providing a branch pipe valve on the first branch pipe, the cooling return water can be introduced only when the conduction states of both the partition valve and the branch pipe valve meet the requirements, improving the accuracy and flexibility of controlling the introduction of the cooling return water. A branch pipe valve with a flow control function can also be set to control the flow rate of the cooling return water. Further, a branch pipe valve can also be provided on the second branch pipe, and its function is similar to that of the branch pipe valve provided on the first branch pipe, and will not be elaborated here.

[0039] In an alternative embodiment, when the partition valve is open and the branch pipe valve is closed, the cooling return water enters the cooling tower through the return pipe; when the partition valve is closed and the branch pipe valve is open, the cooling return water enters the first branch pipe.

[0040] In an alternative embodiment, the air handling unit further includes a fresh air section, a first filtration section, a preheating section, a precooling section, a humidifying section, a reheating section, a fan section, a second filtration section, and an air outlet section.

[0041] In an alternative embodiment, after the fresh air enters the fresh air section of the air handling unit, it sequentially undergoes filtration treatment in the first filtration section, preheating treatment in the preheating section / precooling treatment in the precooling section, humidifying treatment in the humidifying section, reheating treatment in the reheating section / cooling treatment in the reheating section, filtration treatment in the second filtration section, and then is sent to the indoor through the air outlet section.

[0042] In an alternative embodiment, the cooling tower also supplies cooling water to the central air conditioning system through a water supply pipe.

[0043] In summary, in the central air conditioning system provided by the present utility model, when the return water temperature of the cooling tower is relatively high, the partition valve is closed, and the cooling return water is introduced into the reheating section of the air handling unit through the first branch pipe for the reheating section of the air handling unit to utilize the temperature of the cooling return water to exchange heat with the fresh air after being cooled by the air handling unit, so that the temperature of the fresh air after cooling treatment rises to the required temperature, and the temperature of the cooling return water drops after heat dissipation. Since the heat consumed for heating the fresh air after cooling treatment is the heat of the cooling return water, the energy for heating in the reheating section is saved, achieving an energy-saving effect. The cooling return water with a decreased temperature returns to the cooling tower through the second branch pipe. Since the temperature of the cooling return water has dropped, the energy consumed by the cooling tower for cooling the cooling return water is saved, further improving the energy-saving effect.

[0044] Obviously, the above embodiments are merely examples for clear illustration and not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or modifications derived therefrom are still within the protection scope of the present utility model.

Claims

1. A central air conditioning system, characterized in that, The system includes: An air handling unit for refrigeration; the air handling unit includes a reheating section for reheating the fresh air that has been cooled in the air handling unit. A cooling tower that recovers the cooling return water in the central air conditioning system through a return water pipe and cools the cooling return water; a cut-off valve is provided on the return water pipe to control the conduction state of the cooling return water. A first branch pipe, with its first end connected to the first end of the cut-off valve and its second end connected to the water inlet pipe of the reheating section of the air handling unit, for introducing the cooling return water into the reheating section of the air handling unit. A second branch pipe, with its first end connected to the water outlet pipe of the reheating section of the air handling unit and its second end connected to the second end of the cut-off valve, for introducing the water flow discharged from the reheating section of the air handling unit into the return water pipe of the cooling tower.

2. The system according to claim 1, wherein When the cut-off valve is opened, the cooling return water enters the cooling tower through the return water pipe; when the cut-off valve is closed, the cooling return water enters the reheating section of the air handling unit through the first branch pipe at the first end of the cut-off valve, and the water flow discharged from the reheating section of the air handling unit enters the cooling tower through the second branch pipe, the second end of the cut-off valve, and the return water pipe in sequence.

3. The system according to claim 2, wherein In summer, the cut-off valve is closed; in spring, autumn, and winter, the cut-off valve is opened.

4. The system according to claim 2, wherein A cooling tower pump is provided in the cooling tower to pump the cooling return water into the reheating section of the air handling unit when the cut-off valve is closed.

5. The system according to claim 4, characterized in that, The first branch pipe is provided with a branch pipe pump to cooperate with the cooling tower pump to pump the cooling return water into the reheating section of the air handling unit.

6. The system according to any one of claims 1 to 5, characterized in that A branch pipe valve is provided on the first branch pipe to control the conduction state of the first branch pipe.

7. The system according to claim 6, wherein When the cut-off valve is opened and the branch pipe valve is closed, the cooling return water enters the cooling tower through the return water pipe; when the cut-off valve is closed and the branch pipe valve is opened, the cooling return water enters the first branch pipe.

8. The system according to claim 1, wherein The air handling unit further includes a fresh air section, a first filtration section, a preheating section, a precooling section, a humidifying section, a rechilling section, a fan section, a second filtration section, and an air outlet section.

9. The system according to claim 8, wherein After the fresh air enters the fresh air section of the air handling unit, it is sequentially subjected to filtration treatment in the first filtration section, preheating treatment in the preheating section / precooling treatment in the precooling section, humidifying treatment in the humidifying section, heating treatment in the reheating section / cooling treatment in the rechilling section, filtration treatment in the second filtration section, and then sent to the room through the air outlet section.

10. The system according to claim 9, wherein, The cooling tower also supplies cooling water to the central air conditioning system through a supply water pipe.

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