A high efficiency refrigeration system

Abstract

The utility model discloses a kind of efficient refrigeration systems, cooling tower outlet water is connected with the low-temperature zone of cooling side buffer water tank bottom, cooling side buffer water tank bottom low-temperature zone is connected with cooling machine condenser outlet water, cooling machine condenser backwater is connected with the high-temperature zone of cooling side buffer water tank, the high-temperature zone of cooling side buffer water tank is connected with cooling tower backwater, cooling machine evaporator outlet water is connected with the low-temperature zone of refrigeration side buffer water tank, cooling machine evaporator backwater is connected with the medium-temperature zone of refrigeration side buffer water tank, end outlet water is connected with the low-temperature zone of refrigeration side buffer water tank, end backwater is connected with the high-temperature zone of refrigeration side buffer water tank.This scheme when cooling tower and cooling machine synergic cooling mode, cooling tower can be cooled to 26 ℃ by heat exchange of air and water, complete once temperature reduction, this can make cooling machine cooling side inlet water side temperature reduce to 26 ℃ from ambient temperature, make condensing temperature of cooling machine reduce, further make compressor energy consumption reduce.

Description

Technical Field

[0001] This utility model belongs to the field of refrigeration engineering technology, and specifically relates to a high-efficiency refrigeration system. Background Technology

[0002] Current refrigeration systems are mainly divided into three major technical schools: traditional chiller systems based on compression refrigeration cycles, air-source / ground-source heat pump systems, and cooling tower systems utilizing natural cold sources. Traditional chiller systems, operating independently, achieve refrigerant phase change heat transfer through vapor compression cycles and are widely used in large commercial buildings. Their structural characteristic is a series architecture of "chiller-pump-terminal," with typical configurations including a combination of screw chillers and fixed-frequency pumps. Single cooling tower systems rely on sensible heat exchange between air and water, achieving circulating water cooling through a spray-filled packing layer. They are mostly used in industrial circulating cooling scenarios, but their cooling depth is limited by the ambient wet-bulb temperature, typically providing only cooling water above 18°C.

[0003] In recent years, composite systems have begun to emerge, such as switching systems that combine chillers and cooling towers. However, these systems mostly employ simple parallel structures and lack dynamic coordination mechanisms. Domestic and international technological developments exhibit two main trends: European and American companies focus on energy efficiency optimization of magnetic levitation variable frequency chillers, Japanese manufacturers explore the coupled application of radiant cooling and cooling towers, while domestic companies primarily focus on the large-scale application of multi-split systems.

[0004] Existing refrigeration systems have revealed multiple technical bottlenecks in actual operation. In terms of energy consumption, the average annual COP of traditional chiller systems is only 60% of the design value, and the energy efficiency declines significantly under partial load conditions. Single cooling tower systems are significantly constrained by climatic conditions. In the hot and humid environment of summer, the outlet water temperature of the cooling tower is often higher than 28°C, which leads to an increase in the chiller condensing temperature and a decrease in energy efficiency.

[0005] Therefore, this utility model provides a high-efficiency refrigeration system to solve the problems mentioned in the background art. Utility Model Content

[0006] In view of the problems mentioned in the background art, the purpose of this utility model is to provide a high-efficiency refrigeration system. The high-efficiency refrigeration system of this utility model has three refrigeration operation modes, which can reduce compressor energy consumption, improve cooling tower efficiency, reduce system operating energy consumption, and improve adaptability to transitional season conditions.

[0007] To achieve the above-mentioned technical objectives, the technical solution adopted by this utility model is as follows:

[0008] A high-efficiency refrigeration system includes a cooling tower and chiller co-cooling mode: it includes a cooling tower, a cooling-side buffer water tank, a chiller, a refrigeration-side buffer water tank and a terminal connected in sequence, wherein the chiller is equipped with a condenser and a chiller evaporator;

[0009] The chilled side buffer tank is equipped with two porous baffles to form a three-level temperature zone with physical separation. The top is a high-temperature zone, the middle is a medium-temperature zone, and the bottom is a low-temperature zone. The high-temperature zone receives high-load return water from the end, the medium-temperature zone receives return water after heat exchange by the chiller, and the low-temperature zone receives water directly supplied by the chiller.

[0010] The cooling-side buffer water tank also adopts a high-low temperature layered design, with the upper layer being the high-temperature zone and the lower layer being the low-temperature zone, and a porous baffle is set between the high-low temperature zones.

[0011] The cooling tower outlet is connected to the low-temperature zone at the bottom of the cooling-side buffer water tank. The low-temperature zone at the bottom of the cooling-side buffer water tank is connected to the outlet of the chiller condenser. The chiller condenser return water is connected to the high-temperature zone of the cooling-side buffer water tank. The high-temperature zone of the cooling-side buffer water tank is connected to the cooling tower return water. The chiller evaporator outlet is connected to the low-temperature zone of the chilled-side buffer water tank. The chiller evaporator return water is connected to the medium-temperature zone of the chilled-side buffer water tank. The terminal outlet is connected to the low-temperature zone of the chilled-side buffer water tank. The terminal return water is connected to the high-temperature zone of the chilled-side buffer water tank.

[0012] Further specified, the temperature of the high-temperature zone of the frozen side buffer water tank is 18°C, the temperature of the medium-temperature zone is 12°C, and the temperature of the low-temperature zone is 6°C.

[0013] Further specified, the temperature of the high-temperature zone of the cooling-side buffer water tank is 32°C, and the temperature of the low-temperature zone is 26°C.

[0014] Further specified, the end is equipped with an electric three-way regulating valve, which is installed on the end outlet pipe and connected to the end return pipe.

[0015] Further specifying, the high-efficiency refrigeration system also includes a free cooling mode: both the cooling tower outlet and return water are connected to an electric three-way regulating valve, the cooling tower outlet is connected to the medium temperature zone of the chilled side buffer water tank, and the cooling tower return water is connected to the high temperature zone of the chilled side buffer water tank. The electric three-way regulating valve is used to control the part of the cooling tower connected to the chilled side buffer water tank to stop operating, and only the part connected to the cooling tower is operated.

[0016] Furthermore, the high-efficiency refrigeration system also includes a fully open cooling tower mode: the cooling tower outlet water is connected to the low-temperature zone of the cooling-side buffer water tank, the cooling tower return water is connected to the high-temperature zone of the cooling-side buffer water tank, the outlet water of the low-temperature zone of the cooling-side buffer water tank is connected to the outlet water of the low-temperature zone of the freezing-side buffer water tank, and the return water of the low-temperature zone of the cooling-side buffer water tank is connected to the return water of the low-temperature zone of the freezing-side buffer water tank.

[0017] The beneficial effects of this utility model are:

[0018] The high-efficiency refrigeration system of this invention features three refrigeration operation modes:

[0019] In this cooling solution, when the cooling tower and chiller work together for cooling, the cooling tower can naturally cool the chiller's return water from 32°C to 26°C through heat exchange between the air and water, completing one cooling cycle. This lowers the inlet water temperature on the chiller's cooling side from ambient temperature to 26°C, thus reducing the chiller's condensing temperature and further reducing compressor energy consumption.

[0020] In the free cooling mode, during transitional seasons when outdoor humidity and temperature are sufficiently low, the cooling tower can directly cool the system return water to or near the wet-bulb temperature. If this temperature meets the terminal cooling demand, the chiller does not need to be started; the system is cooled solely through the plate heat exchanger. In this mode, there is no chiller power loss, the cooling tower efficiency is at its highest, and the system operating energy consumption is at its lowest.

[0021] In the fully open cooling tower mode, the system does not need to start the chiller. It mainly relies on the cooling tower for cooling and does not depend on a specific low wet-bulb temperature (such as the wet-bulb temperature in the free cooling mode). The system is connected to a dual buffer tank via a water pump, which breaks the environmental limitations of traditional free cooling and improves the adaptability of the system to the transitional season. Attached Figure Description

[0022] This utility model can be further illustrated by the non-limiting embodiments given in the accompanying drawings;

[0023] Figure 1 This is a schematic diagram illustrating the operating principle of a high-efficiency refrigeration system according to an embodiment of the present invention.

[0024] Figure 2 This is a system operation mode diagram of an embodiment of a high-efficiency refrigeration system of this utility model. Detailed Implementation

[0025] In the description of this utility model, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this utility model, unless otherwise stated, "a plurality of" means two or more.

[0026] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0027] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0028] like Figure 1 As shown, this utility model discloses a high-efficiency refrigeration system, which includes a cooling tower and a chiller co-cooling mode: it includes a cooling tower, a cooling-side buffer water tank, a chiller, a refrigeration-side buffer water tank and a terminal connected in sequence, and the chiller is equipped with a condenser and a chiller evaporator.

[0029] The chilled side buffer tank is equipped with two porous baffles to form a three-level temperature zone with physical separation. The top is a high-temperature zone, the middle is a medium-temperature zone, and the bottom is a low-temperature zone. The high-temperature zone receives high-load return water from the end, the medium-temperature zone receives return water after heat exchange by the chiller, and the low-temperature zone receives water directly supplied by the chiller.

[0030] The cooling-side buffer water tank also adopts a high-low temperature layered design, with the upper layer being the high-temperature zone and the lower layer being the low-temperature zone, and a porous baffle is set between the high-low temperature zones.

[0031] The cooling tower outlet is connected to the low-temperature zone at the bottom of the cooling-side buffer water tank. The low-temperature zone at the bottom of the cooling-side buffer water tank is connected to the outlet of the chiller condenser. The chiller condenser return water is connected to the high-temperature zone of the cooling-side buffer water tank. The high-temperature zone of the cooling-side buffer water tank is connected to the cooling tower return water. The chiller evaporator outlet is connected to the low-temperature zone of the chilled-side buffer water tank. The chiller evaporator return water is connected to the medium-temperature zone of the chilled-side buffer water tank. The terminal outlet is connected to the low-temperature zone of the chilled-side buffer water tank. The terminal return water is connected to the high-temperature zone of the chilled-side buffer water tank.

[0032] In the practical application of this embodiment, the temperature of the high-temperature zone of the freezing side buffer tank is 18°C, the temperature of the medium-temperature zone is 12°C, and the temperature of the low-temperature zone is 6°C.

[0033] In the practical application of this embodiment, the temperature of the high-temperature zone of the cooling-side buffer water tank is 32°C, and the temperature of the low-temperature zone is 26°C.

[0034] In the practical application of this embodiment, the end is equipped with an electric three-way regulating valve, which is installed on the end water outlet pipe and connected to the end water return pipe.

[0035] In practical applications of this embodiment, the high-efficiency refrigeration system also includes a free cooling mode, such as... Figure 2 Only module 2 operates: Both the cooling tower's outlet and return water are connected to an electric three-way regulating valve. The cooling tower outlet is connected to the medium-temperature zone of the chilled-side buffer water tank, and the cooling tower return water is connected to the high-temperature zone of the chilled-side buffer water tank. The electric three-way regulating valve controls the portion of the cooling tower connected to the chilled-side buffer water tank to stop operating, allowing only the connection between the chilled-side buffer water tank and the cooling tower to operate. The final outlet water temperature is 12℃ (the two buffer water tanks are interconnected; since there is no chiller supplying 6℃ water to the chilled-side buffer water tank, the low-temperature zone of the chilled-side buffer water tank is also 12℃).

[0036] In practical applications of this embodiment, the high-efficiency refrigeration system also includes a fully open cooling tower mode, such as... Figure 2Only module 3 operates: the cooling tower outlet water is connected to the low-temperature zone of the cooling-side buffer water tank, and the cooling tower return water is connected to the high-temperature zone of the cooling-side buffer water tank. Under this condition, the outlet water temperature of the cooling-side buffer water tank is 6℃, and the return water temperature is 12℃. The outlet water of the low-temperature zone of the cooling-side buffer water tank is connected to the outlet water of the low-temperature zone of the chilled-side buffer water tank, and the return water of the low-temperature zone of the cooling-side buffer water tank is connected to the return water of the low-temperature zone of the chilled-side buffer water tank. The return water temperature at the end remains at 18℃. After entering the chilled-side buffer water tank, this return water exchanges heat with the low-temperature water in the low-temperature zone of the chilled-side buffer water tank, and the temperature in the middle zone of the chilled-side buffer water tank is stably maintained at 12℃.

[0037] like Figure 1 and Figure 2 As shown, the working principle of this utility model is as follows:

[0038] In this scheme, when the cooling tower and chiller work together for cooling, the cooling tower first cools the chiller's return water (32℃) to 26℃. The chiller then performs a second cooling on the water cooled by the cooling tower (supply water 26℃, return water 32℃; supply water 6℃, return water 12℃) before supplying cooling to the end users. Through heat exchange between air and water, the cooling tower naturally cools the chiller's return water from 32℃ to 26℃, completing one cooling cycle. This lowers the chiller's cooling-side inlet water temperature from ambient temperature to 26℃, thus reducing the chiller's condensing temperature and further reducing compressor energy consumption.

[0039] In the free cooling mode, during transitional seasons when outdoor humidity and temperature are sufficiently low, the cooling tower can directly cool the system return water (e.g., 18°C) to or near the wet-bulb temperature (e.g., 12°C; the closer the outlet water temperature is to the wet-bulb temperature, the higher the cooling efficiency). If this temperature meets the terminal cooling demand, the chiller does not need to be started; the system is cooled only through the plate heat exchanger (to avoid contamination of the indoor circulating water by the cooling water). In this mode, there is no chiller power loss, the cooling tower efficiency is the highest, and the system operating energy consumption is the lowest.

[0040] In the fully operational cooling tower mode, this solution may not be suitable for all ambient temperatures during transitional seasons, but the terminal demand is relatively low at these times, eliminating the need to start the chiller. Only the cooling tower needs to be activated to meet terminal demand (supply water 6℃, return water 12℃). In this mode, the pump between the chilled water side buffer tank and the cooling water side buffer tank starts, directly connecting the two. This allows the cooling tower outlet water to be directly used for terminal cooling after passing through a plate heat exchanger. The system does not require chiller activation, relying primarily on the cooling tower for cooling, and it does not depend on specific low wet-bulb temperatures (such as the wet-bulb temperature in free cooling mode). By connecting the two buffer tanks via pumps, it overcomes the environmental limitations of traditional free cooling, improving adaptability to transitional season conditions.

[0041] Terminal Adaptive Adjustment: The inlet pipe of the refrigeration system terminal (inlet water 6℃, outlet water 18℃) is equipped with a three-way valve, which can adjust the supply water temperature according to the actual load requirements of the terminal (for example, if the terminal does not require such a low supply water temperature of 6℃, a portion of the return water can be mixed to raise the temperature). The advantages of this design are: it can utilize the heat from the return water temperature and adjust it according to the terminal load requirements, which can provide a more stable terminal environment and improve terminal comfort; moreover, using the return water temperature adjustment not only allows for full heat recovery and utilization of the system return water, but also reduces the frequency of chiller start-ups and shutdowns, reduces machine wear, and lowers later maintenance costs.

[0042] Dual-buffer water tank regulation: ① The chilled water tank is divided into three temperature zones: 18℃, 12℃, and 6℃. The system terminal mainly obtains cooling capacity from the low-temperature zone (6℃) to meet the cooling demand; the system return water enters the high-temperature zone (18℃), which is suitable for free cooling mode operation; during the heat exchange between the high and low temperature zones, a medium temperature zone (12℃) is naturally formed, and the water in this zone is used as the chiller's chilled side return water. If the system's 18℃ return water is directly used as the chiller's chilled side return water, the temperature difference on the chilled side will be greatly increased, and the chiller will need to start cooling from 18℃, significantly increasing the chiller's energy consumption. ② The cooling-side water tank is divided into two temperature zones: 32°C and 26°C. The cooling tower cools outdoor air and outputs 26°C chilled water into the low-temperature zone, from which the chiller obtains the required 26°C water supply for the cooling side. After condensation and heat exchange within the chiller, the 26°C water is heated to 32°C and becomes return water, entering the high-temperature zone of the cooling side. Simultaneously, it returns to the cooling tower as return water, where it is cooled again to 26°C, thus completing the cooling-side cycle. The advantages of this design are: ① It can significantly reduce system energy consumption. ② It effectively improves system stability: The temperature zone design of the water tank can effectively buffer water flow temperature fluctuations, avoiding the impact of sudden water temperature changes on the cooling quality of the terminal or the operating conditions of the chiller. At the same time, the clear water flow path and temperature zones make the operation of each part of the system more orderly, reduce the risk of failure, and ensure overall operational stability. ③ Optimize energy utilization efficiency: The cooling tower pre-cools the chiller (directly cooling it from the outdoor temperature to 26℃), reducing the chiller's operating energy consumption. Furthermore, the chiller's return water is reused in the cooling tower for cooling, achieving efficient energy recycling and improving the overall energy efficiency of the system.

[0043] In addition, it can be designed as a distributed system: distributed cooling refers to dividing the cooling system into multiple small areas, each operating independently and connected by pipes to achieve cooling. Unlike traditional distributed systems, the areas in this system are connected by buffer tanks, ensuring that each part does not interfere with the others. Therefore, the cold source is not limited to chillers and cooling towers; multiple cold sources can be coupled according to actual project needs, and the cold sources can be distributed according to actual installation requirements. This increases the flexibility and versatility of the cooling system.

[0044] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model are also considered equivalent.

Claims

1. A high-efficiency refrigeration system, characterized in that, The high-efficiency refrigeration system includes a cooling tower and chiller co-cooling mode: it includes a cooling tower, a cooling-side buffer water tank, a chiller, a refrigeration-side buffer water tank and a terminal connected in sequence, and the chiller is equipped with a condenser and a chiller evaporator; The chilled side buffer tank is equipped with two porous baffles to form a three-level temperature zone with physical separation. The top is a high-temperature zone, the middle is a medium-temperature zone, and the bottom is a low-temperature zone. The high-temperature zone receives high-load return water from the end, the medium-temperature zone receives return water after heat exchange by the chiller, and the low-temperature zone receives water directly supplied by the chiller. The cooling-side buffer water tank also adopts a high-low temperature layered design, with the upper layer being the high-temperature zone and the lower layer being the low-temperature zone, and a porous baffle is set between the high-low temperature zones. The cooling tower outlet is connected to the low-temperature zone at the bottom of the cooling-side buffer water tank. The low-temperature zone at the bottom of the cooling-side buffer water tank is connected to the outlet of the chiller condenser. The chiller condenser return water is connected to the high-temperature zone of the cooling-side buffer water tank. The high-temperature zone of the cooling-side buffer water tank is connected to the cooling tower return water. The chiller evaporator outlet is connected to the low-temperature zone of the chilled-side buffer water tank. The chiller evaporator return water is connected to the medium-temperature zone of the chilled-side buffer water tank. The terminal outlet is connected to the low-temperature zone of the chilled-side buffer water tank. The terminal return water is connected to the high-temperature zone of the chilled-side buffer water tank.

2. The high-efficiency refrigeration system according to claim 1, characterized in that: The temperature of the high-temperature zone of the refrigerated buffer tank is 18°C, the temperature of the medium-temperature zone is 12°C, and the temperature of the low-temperature zone is 6°C.

3. The high-efficiency refrigeration system according to claim 1, characterized in that: The temperature of the high-temperature zone of the cooling-side buffer water tank is 32°C, and the temperature of the low-temperature zone is 26°C.

4. The high-efficiency refrigeration system according to claim 1, characterized in that: The end is equipped with an electric three-way regulating valve, which is located on the end outlet pipe and connected to the end return pipe.

5. The high-efficiency refrigeration system according to claim 1, characterized in that, The high-efficiency refrigeration system also includes a free cooling mode: both the outlet and return water of the cooling tower are connected to an electric three-way regulating valve. The outlet water of the cooling tower is connected to the medium temperature zone of the chilled side buffer water tank, and the return water of the cooling tower is connected to the high temperature zone of the chilled side buffer water tank. The electric three-way regulating valve is used to control the part of the cooling tower connected to the chilled side buffer water tank to stop operating, and only the part connected to the cooling tower is operated.

6. The high-efficiency refrigeration system according to claim 1, characterized in that, The high-efficiency refrigeration system also includes a fully open cooling tower mode: the cooling tower outlet water is connected to the low-temperature zone of the cooling-side buffer water tank, the cooling tower return water is connected to the high-temperature zone of the cooling-side buffer water tank, the outlet water of the low-temperature zone of the cooling-side buffer water tank is connected to the outlet water of the low-temperature zone of the freezing-side buffer water tank, and the return water of the low-temperature zone of the cooling-side buffer water tank is connected to the return water of the low-temperature zone of the freezing-side buffer water tank.

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