Wastewater heat recovery system of carbon dioxide transcritical system

Abstract

The utility model provides a waste water heat recovery system of a carbon dioxide transcritical system, which comprises a carbon dioxide compressor, a first condenser, a second condenser, an electromagnetic valve, an expansion valve, an evaporator, a hot water tank, a water pump, a sewage tank, a sewage circulating pump and a sewage discharge pump. The carbon dioxide refrigerant is liquefied in the first condenser and the second condenser to release heat, so that double gradient temperature rise of low-temperature wastewater is realized, high-temperature water is prepared and used in the production field, the efficiency is improved, the power input is reduced, and meanwhile, part of high-temperature wastewater can be discharged after being cooled; dual driving of heating, conveying and utilizing and cooling and discharging of the wastewater can be realized, and the wastewater treatment performance is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of heat recovery of a transcritical carbon dioxide system, in particular to a wastewater heat recovery system of a carbon dioxide transcritical system. Background Art

[0002] Transcritical CO2 refrigeration system is an advanced refrigeration technology widely used in commercial and industrial fields. This system uses CO2 as a refrigerant and compresses it to a state exceeding its critical pressure and temperature to achieve a cooling effect.

[0003] The key features of this refrigeration system include: Environmental friendliness: The transcritical carbon dioxide refrigeration system uses carbon dioxide as a refrigerant, which has less impact on the environment than traditional Freon refrigerants. Carbon dioxide is a natural, non-toxic, harmless, and odorless gas that does not damage the ozone layer of the atmosphere or cause a greenhouse effect.

[0004] High efficiency: Transcritical CO2 refrigeration systems are generally more efficient than conventional refrigeration systems. CO2 has a relatively low critical temperature, so its cycle efficiency is higher than other refrigerants in high temperature environments.

[0005] Wide temperature range: Transcritical carbon dioxide refrigeration system is suitable for a wide temperature range and can achieve refrigeration effects from low temperature to high temperature.

[0006] Safety: Transcritical CO2 refrigeration system is safer than other refrigeration systems. CO2 is a non-toxic and harmless gas with low safety risks during use and handling.

[0007] Stability: Carbon dioxide is a stable refrigerant that is not easily decomposed or degraded, so the system operation stability is relatively high.

[0008] However, in the actual production process, the wastewater coming out of the factory contains the required heat, but due to the low water temperature, its application value is small, and the wastewater heat cannot be effectively applied according to actual production needs. Utility Model Content

[0009] In view of this, the technical problem to be solved by the utility model is: how to provide a wastewater heat recovery system for a carbon dioxide transcritical system to produce high-temperature hot water for process production by utilizing the high efficiency of carbon dioxide transcritical water production.

[0010] To achieve the above-mentioned purpose, the utility model proposes a wastewater heat recovery system for a carbon dioxide transcritical system, which includes: a carbon dioxide compressor, a first condenser, a second condenser, a solenoid valve, an expansion valve, an evaporator, a hot water tank, a water pump, a sewage tank, a sewage circulation pump, and a sewage discharge pump;

[0011] The sewage tank includes a high-temperature chamber and a low-temperature chamber, one end of the high-temperature chamber is connected to the water supply pipe, and the other end of the high-temperature chamber is connected to the sewage circulation pump, and the sewage circulation pump transfers the wastewater in the high-temperature chamber into the low-temperature chamber through the pipeline connected to the evaporator;

[0012] The hot water tank is used to contain water to be heated, and the end of the hot water tank is connected to the water pump, and the water pump heats the water in the hot water tank through the second condenser and the first condenser and then sends it out;

[0013] The first condenser, the second condenser and the evaporator are connected by pipelines and are used to transport carbon dioxide refrigerant. The carbon dioxide compressor is connected between the evaporator and the first condenser, and the solenoid valve and the expansion valve are connected between the second condenser and the evaporator.

[0014] Furthermore, one end of the low-temperature chamber is connected to the sewage discharge pump.

[0015] Furthermore, the carbon dioxide compressor heats and pressurizes the gaseous carbon dioxide refrigerant delivered by the evaporator and delivers it to the first condenser for liquefaction, and part of the carbon dioxide refrigerant is delivered from the first condenser to the second condenser and enters the evaporator through the solenoid valve and the expansion valve.

[0016] Furthermore, a partition is arranged inside the sewage tank, and the partition divides the sewage tank into the high-temperature chamber and the low-temperature chamber.

[0017] Compared with the related art, the utility model proposes a wastewater heat recovery system for a carbon dioxide transcritical system, which has the beneficial effect that: in the wastewater heat recovery system, the carbon dioxide refrigerant is liquefied and releases heat in the first condenser and the second condenser to achieve a double gradient heating of the low-temperature wastewater, so as to produce high-temperature water and use it in the production field, improve efficiency, reduce electricity input, and at the same time, part of the high-temperature wastewater can be cooled and then discharged, which can realize the dual drive of heating, transportation and utilization of wastewater and cooling and discharge, greatly improving the wastewater treatment performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of a wastewater heat recovery system of a carbon dioxide transcritical system in an embodiment of the present utility model. DETAILED DESCRIPTION

[0019] The utility model is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0020] Reference Figure 1As shown, the utility model proposes a wastewater heat recovery system for a carbon dioxide transcritical system, which includes: a carbon dioxide compressor 1, a first condenser 2, a second condenser 3, a solenoid valve 4, an expansion valve 5, an evaporator 6, a hot water tank 7, a water pump 8, a sewage tank 9, a sewage circulation pump 10, and a sewage discharge pump 11.

[0021] A partition is arranged inside the sewage tank 9, and the partition divides the sewage tank 9 into a high-temperature chamber 92 and a low-temperature chamber 91. The sewage tank 9 includes a high-temperature chamber 92 and a low-temperature chamber 91. One end of the high-temperature chamber 92 is connected to the water supply pipe, and the other end of the high-temperature chamber 92 is connected to the sewage circulation pump 10. The sewage circulation pump 10 passes the wastewater in the high-temperature chamber 92 into the low-temperature chamber 91 through the pipeline connected to the evaporator 6, so that part of the high-temperature wastewater can be cooled on the refrigeration side and then transported at a lower temperature to prevent the wastewater temperature from being too high during the discharge process. Among them, the low-temperature chamber 91 and the high-temperature chamber 92 are both arranged in the sewage tank 9, so that the liquid flows on both sides can be heat exchanged, so as to achieve preliminary cooling of the liquid flow in the high-temperature chamber 92.

[0022] The hot water tank 7 is used to contain the water flow to be heated. The end of the hot water tank 7 is connected to the water pump 8. The water pump 8 heats the water flow in the hot water tank 7 through the second condenser 3 and the first condenser 2 and then sends it out, making full use of the transcritical carbon dioxide refrigeration system that is suitable for a wider temperature range, thereby realizing double gradient heating during the flow through the second condenser 3 and the first condenser 2.

[0023] The first condenser 2, the second condenser 3 and the evaporator 6 are connected by pipelines and are used to transport carbon dioxide refrigerant. The carbon dioxide compressor 1 is connected between the evaporator 6 and the first condenser 2, and the solenoid valve 4 and the expansion valve 5 are connected between the second condenser 3 and the evaporator 6.

[0024] One end of the low temperature chamber 91 is connected to a sewage discharge pump 11, and the sewage discharge pump 11 discharges the low temperature waste water after the temperature is reduced.

[0025] The carbon dioxide compressor 1 heats and pressurizes the gaseous carbon dioxide refrigerant delivered by the evaporator 6 and delivers it to the first condenser 2 for liquefaction, and part of the carbon dioxide refrigerant is delivered from the first condenser 2 to the second condenser 3 and enters the evaporator 6 through the solenoid valve 4 and the expansion valve 5, and evaporates and absorbs heat in the evaporator 6, and is compressed by the carbon dioxide compressor 1 to enter the next refrigeration cycle.

[0026] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the utility model, rather than to limit it. Although the utility model has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the various embodiments of the utility model.

Claims

1. A wastewater heat recovery system for a carbon dioxide transcritical system, characterized in that: It includes: a carbon dioxide compressor, a first condenser, a second condenser, a solenoid valve, an expansion valve, an evaporator, a hot water tank, a water pump, a sewage tank, a sewage circulation pump, and a sewage discharge pump; The sewage tank includes a high-temperature chamber and a low-temperature chamber, one end of the high-temperature chamber is connected to the water supply pipe, and the other end of the high-temperature chamber is connected to the sewage circulation pump, and the sewage circulation pump transfers the wastewater in the high-temperature chamber into the low-temperature chamber through the pipeline connected to the evaporator; The hot water tank is used to contain water to be heated, and the end of the hot water tank is connected to the water pump, and the water pump heats the water in the hot water tank through the second condenser and the first condenser and then sends it out; The first condenser, the second condenser and the evaporator are connected by pipelines and are used to transport carbon dioxide refrigerant. The carbon dioxide compressor is connected between the evaporator and the first condenser, and the solenoid valve and the expansion valve are connected between the second condenser and the evaporator.

2. The wastewater heat recovery system of the carbon dioxide transcritical system according to claim 1, characterized in that: One end of the low temperature chamber is connected to the sewage discharge pump.

3. The wastewater heat recovery system of the carbon dioxide transcritical system according to claim 1, characterized in that: The carbon dioxide compressor heats and pressurizes the gaseous carbon dioxide refrigerant delivered by the evaporator and delivers it to the first condenser for liquefaction, and part of the carbon dioxide refrigerant is delivered from the first condenser to the second condenser and enters the evaporator through the solenoid valve and the expansion valve.

4. The wastewater heat recovery system of the carbon dioxide transcritical system according to claim 1, characterized in that: A partition is arranged inside the sewage tank, and the partition divides the sewage tank into the high-temperature chamber and the low-temperature chamber.

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