A refrigerant liquefier based on an ejector

Abstract

The utility model discloses a kind of based on the refrigerant liquefaction device of injection, belong to refrigerant liquefaction technical field.Aiming at the problem of higher energy consumption when refrigerant liquefaction in prior art, the utility model recycles liquid storage tank flash gas pressure energy by ejector, reduces compressor load and system energy consumption.Main heat exchanger realizes the heat exchange between injection backflow and main liquid stream, completes internal cold circulation utilization.Coil pipe type main heat exchanger is wound in liquid storage tank outer wall, directly utilizes low-temperature refrigerant in tank, reduces pipeline cold loss, realizes device compactification.Coil pipe and tank wall are filled with heat-conducting material to strengthen heat transfer.Adjusting valve is arranged at the outlet of injection path of three-way flow divider, to facilitate optimizing injection working condition.Upright cylindrical liquid storage tank promotes gas-liquid separation, guarantees injection gas dryness.The device effectively improves refrigerant liquefaction energy efficiency through the above-mentioned structure synergistic effect.

Description

Technical Field

[0001] This utility model belongs to the field of refrigerant liquefaction technology, specifically relating to a refrigerant liquefaction device based on ejection. Background Technology

[0002] In traditional small-scale refrigerant liquefaction devices, high-pressure refrigerant is liquefied by absorbing heat in the storage tank after throttling. This process inevitably generates some low-temperature, low-pressure flash gas. Currently, the common approach is to directly return this flash gas to the compressor's suction port. This direct return method has significant energy efficiency drawbacks: the flash gas pressure is extremely low, requiring the compressor to expend additional power to recompress it to the condensing pressure, increasing the overall system energy consumption. Simultaneously, there is a lack of effective heat exchange between this directly returned low-temperature gas and the high-temperature, high-pressure liquid flowing from the condenser, resulting in insufficient utilization of the system's internal cooling capacity. Furthermore, direct return may cause liquid to be carried into the compressor suction, affecting operational stability. Therefore, there is an urgent need in existing technology for a liquefaction device structure that can effectively recover the pressure energy of the flash gas and achieve efficient utilization of internal cooling capacity to solve the core problem of high system energy consumption.

[0003] This invention aims to reduce energy consumption by providing a refrigerant liquefaction device based on ejection. Utility Model Content

[0004] In view of one or more of the above-mentioned defects or improvement needs of the prior art, this utility model provides a refrigerant liquefaction device based on ejector, which has the advantage of energy saving.

[0005] To achieve the above objectives, this utility model provides a refrigerant liquefaction device based on an ejector, including a compressor, a condenser, a throttling element and a liquid storage tank connected by pipelines, and also including an ejector and a main heat exchanger; The outlet of the condenser is connected to the inlet of a three-way distributor. The first outlet of the three-way distributor is connected to the first channel inlet of the main heat exchanger via a pipeline, and the second outlet of the three-way distributor is connected to the high-pressure working fluid inlet of the ejector via a pipeline. The top gas phase space of the liquid storage tank is connected to the low-pressure ejector fluid inlet of the ejector through a flash gas recovery pipe, and the mixed fluid outlet of the ejector is connected to the second channel inlet of the main heat exchanger through a mixed fluid return pipe. The first channel outlet of the main heat exchanger is connected to the inlet of the throttling element through a pipeline, and the outlet of the throttling element leads to the interior of the liquid storage tank. The second channel outlet of the main heat exchanger is connected to the suction port of the compressor through a compressor return branch pipe.

[0006] As a further improvement of this utility model, the main heat exchanger is a coil heat exchanger, and the coil is tightly wound around the outer wall of the liquid storage tank.

[0007] As a further improvement of this utility model, a thermally conductive material is filled between the coil and the outer wall of the liquid storage tank.

[0008] As a further improvement of this utility model, an adjustable valve is provided at the second outlet of the three-way diverter.

[0009] As a further improvement of this utility model, the liquid storage tank is a vertical cylindrical structure.

[0010] As a further improvement of this utility model, the throttling element is a capillary tube or a thermostatic expansion valve.

[0011] As a further improvement of this utility model, the main heat exchanger is a plate heat exchanger.

[0012] In summary, the beneficial effects of the above-described technical solutions conceived by this utility model compared with the prior art include: This invention discloses a refrigerant liquefaction device based on an ejector. The ejector recovers the pressure energy of the flash gas in the storage tank and converts it into useful ejector power, reducing the compressor load and system energy consumption. A main heat exchanger is used to exchange heat between the low-temperature mixed fluid output from the ejector and the mainstream high-pressure liquid, achieving the recycling of internal cooling capacity and improving the pre-cooling degree of the main liquid flow and the refrigeration efficiency after throttling. The main heat exchanger is designed as a coil wound around the outer wall of the storage tank, allowing the heat exchange process to directly utilize the low temperature of the liquid refrigerant inside the tank, reducing the pipe heat loss present in traditional independent heat exchangers, while also achieving a compact and modular device. Filling the space between the main heat exchanger coil and the outer wall of the storage tank with thermally conductive material further reduces contact thermal resistance and enhances the heat transfer process. A regulating valve is installed at the ejector outlet of the three-way distributor to facilitate optimization of the ejector's operating state according to working conditions. The upright cylindrical storage tank facilitates gas-liquid separation, ensuring the dryness of the gas drawn into the ejector. Plate heat exchangers, as an alternative to the main heat exchanger, provide another high-efficiency heat exchange option for the plant. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the refrigerant liquefaction device based on ejector according to this utility model; Figure 2 This utility model Figure 1 Schematic diagram of the structure at point A in the middle; Figure 3 This utility model Figure 1 Schematic diagram of the structure at point B; Figure 4 This utility model Figure 1 Schematic diagram of the structure at point C; Figure 5 This is a schematic diagram of the structure of the second embodiment of the present utility model.

[0014] In all the accompanying drawings, the same reference numerals denote the same technical features, specifically: 1. Compressor; 2. Condenser; 3. Three-way distributor; 4. Ejector; 5. Main heat exchanger; 6. Liquid storage tank; 7. Throttling element; 8. Flash gas recovery pipe; 9. Mixed fluid return pipe; 10. Compressor return gas branch pipe; 11 First Exit; 12 Second Exit; First Channel 51; Second Channel 52. Detailed Implementation

[0015] 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.

[0016] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The terms “comprising,” “including,” etc., as used herein indicate the presence of the stated features, steps, operations, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, or components.

[0017] All terms used herein (including technical and scientific terms) have the meanings commonly understood by those skilled in the art, unless otherwise defined. It should be noted that the terms used herein are to be interpreted in a manner consistent with the context of this specification, and not in an idealized or overly rigid way.

[0018] Example 1

[0019] This embodiment provides a refrigerant liquefaction device based on an ejector. Its core is to recover the pressure of flash gas through an ejector and to achieve efficient cold energy recovery through an integrated main heat exchanger.

[0020] As shown in the figure Figure 1-4 As shown, the device includes a compressor 1, a condenser 2, a three-way distributor 3, an ejector 4, a main heat exchanger 5, a liquid receiver 6, a throttling element 7, a flash gas recovery pipe 8, a mixed fluid return pipe 9, and a compressor return branch pipe 10.

[0021] The connection relationships and functions of each component are as follows: The outlet of the compressor 1 is connected to the inlet of the condenser 2 via a pipeline, which is used to compress the refrigerant and deliver it to the condenser 2.

[0022] The outlet of the condenser 2 is connected to the inlet of the three-way distributor 3. The three-way distributor 3 has a first outlet 11 and a second outlet 12.

[0023] The first outlet 11 of the three-way distributor 3 is connected to the inlet of the first channel 51 of the main heat exchanger 5 through a pipeline, forming the main refrigeration flow path.

[0024] The second outlet 12 of the three-way diverter 3 is connected to the high-pressure working fluid inlet of the ejector 4 through a pipeline, providing a power source for the ejector 4.

[0025] The top gas phase space of the storage tank 6 is connected to the low-pressure ejector fluid inlet of the ejector 4 through the flash gas recovery pipe 8, for recovering the flash gas generated in the tank.

[0026] The mixed fluid outlet of the ejector 4 is connected to the inlet of the second channel 52 of the main heat exchanger 5 via the mixed fluid return pipe 9.

[0027] The outlet of the first channel 51 of the main heat exchanger 5 is connected to the inlet of the throttling element 7 via a pipeline, and the outlet of the throttling element 7 leads to the interior of the liquid storage tank 6.

[0028] The outlet of the second channel 52 of the main heat exchanger 5 is connected to the suction port of the compressor 1 through the compressor return branch pipe 10 to complete the system circulation.

[0029] As a preferred embodiment, the main heat exchanger 5 is a coil-type heat exchanger, with the coil tightly wound around the outer wall of the liquid storage tank 6 to form an integrated structure. To further improve heat exchange efficiency, a high-performance thermally conductive material (such as thermally conductive silicone grease or thermally conductive epoxy resin) can be filled between the coil and the outer wall of the liquid storage tank 6.

[0030] The throttling element 7 is preferably a capillary tube or a thermostatic expansion valve. The liquid storage tank 6 is preferably a vertical cylindrical structure to facilitate gas-liquid separation. To optimize the ejection effect, an adjustable valve can be installed at the second outlet 12 of the three-way diverter 3 to precisely control the flow rate of the high-pressure liquid leading to the ejector 4.

[0031] Example 2

[0032] The main difference between this embodiment and Embodiment 1 lies in the specific form of the main heat exchanger 5 and its installation method.

[0033] like Figure 5As shown, in this embodiment, the main heat exchanger 5 is a plate heat exchanger. Since the plate heat exchanger is an independent rigid module and cannot be wound around the liquid storage tank like a coil, it is fixedly installed near the liquid storage tank 6 by a bracket.

[0034] In this embodiment, all components except the main heat exchanger 5 and their connections are the same as in the first embodiment. That is, the main high-pressure liquid from the first outlet 11 of the three-way distributor 3 and the mixed fluid from the ejector 4 transported through the mixed fluid return pipe 9 are respectively connected to the two independent channel inlets of the plate heat exchanger 5; after heat exchange is completed, the outlet of the first channel 51 of the plate heat exchanger 5 is connected to the throttling element 7, and the outlet of its second channel 52 is connected back to the compressor 1 through the compressor return branch pipe 10.

[0035] Although this embodiment does not achieve the ultimate compact integration of the first embodiment, it utilizes the high heat exchange efficiency of the plate heat exchanger itself, and can also effectively realize the core functions of refrigerant liquefaction and energy recovery, providing another feasible way to implement the device.

[0036] Working Principle: When this device is in operation, compressor 1 compresses the refrigerant gas into a high-temperature, high-pressure state and sends it to condenser 2, where the refrigerant condenses into a high-pressure liquid. This liquid flows out of condenser 2 and enters a three-way distributor 3, where it is divided into two paths: one path serves as the main refrigeration flow, passing through the first outlet 11 and entering the first channel 51 of the main heat exchanger 5; the other path serves as the power flow, passing through the second outlet 12 and entering the high-pressure working fluid inlet of ejector 4. Ejector 4 utilizes the high pressure of the power flow to generate an ejector effect, continuously drawing the low-temperature, low-pressure flash gas from the top of the liquid storage tank 6 to its low-pressure ejector fluid inlet through flash gas recovery pipe 8. The two fluids mix within ejector 4, forming a medium-pressure gas-liquid mixture, which enters the second channel 52 of the main heat exchanger 5 through mixed fluid return pipe 9. Inside the main heat exchanger 5, the low-temperature mixture from the ejector in the second channel 52 undergoes counter-current heat exchange with the high-pressure main refrigerant liquid flow in the first channel 51, achieving deep pre-cooling of the main refrigerant liquid flow. The pre-cooled high-pressure liquid is throttled and depressurized by the throttling element 7, becoming a low-temperature, low-pressure mist fluid that is injected into the liquid storage tank 6 to complete the refrigeration liquefaction process. Meanwhile, the fluid in the second channel 52, which has completed its heat exchange task, is transformed into a low-temperature, low-pressure gas and returns to the suction port of the compressor 1 through the compressor return branch pipe 10, thus forming a complete energy-saving cycle.

[0037] In summary, this invention recovers the pressure energy of the flash gas in the storage tank via an ejector, converting it into useful ejector power, thus reducing the compressor load and system energy consumption. The main heat exchanger facilitates heat exchange between the low-temperature mixed fluid output from the ejector and the mainstream high-pressure liquid, enabling the recycling of internal cooling capacity and improving the pre-cooling degree of the main liquid flow and the refrigeration efficiency after throttling. Designing the main heat exchanger as a coil wound around the outer wall of the storage tank allows the heat exchange process to directly utilize the low temperature of the liquid refrigerant inside the tank, reducing the pipe heat loss present in traditional independent heat exchangers, while also achieving a compact and modular design. Filling the space between the main heat exchanger coil and the outer wall of the storage tank with thermally conductive material further reduces contact thermal resistance and enhances the heat transfer process. A regulating valve is installed at the ejector outlet of the three-way distributor to facilitate optimization of the ejector's operating state according to working conditions. The upright cylindrical storage tank facilitates gas-liquid separation, ensuring the dryness of the gas drawn into the ejector. Plate heat exchangers, as an alternative to the main heat exchanger, provide another high-efficiency heat exchange option for the plant.

[0038] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A refrigerant liquefaction device based on ejector, comprising a compressor (1), a condenser (2), a throttling element (7), and a liquid receiver (6) connected by pipelines, characterized in that: It also includes an ejector (4) and a main heat exchanger (5); The outlet of the condenser (2) is connected to the inlet of a three-way distributor (3), the first outlet (11) of the three-way distributor (3) is connected to the inlet of the first channel (51) of the main heat exchanger (5) through a pipeline, and the second outlet (12) of the three-way distributor (3) is connected to the high-pressure working fluid inlet of the ejector (4) through a pipeline. The top gas phase space of the liquid storage tank (6) is connected to the low-pressure ejector fluid inlet of the ejector (4) through a flash gas recovery pipe (8), and the mixed fluid outlet of the ejector (4) is connected to the inlet of the second channel (52) of the main heat exchanger (5) through a mixed fluid return pipe (9). The outlet of the first channel (51) of the main heat exchanger (5) is connected to the inlet of the throttling element (7) through a pipeline. The outlet of the throttling element (7) leads to the interior of the liquid storage tank (6). The outlet of the second channel (52) of the main heat exchanger (5) is connected to the suction port of the compressor (1) through a compressor return branch pipe (10).

2. The refrigerant liquefaction device according to claim 1, characterized in that: The main heat exchanger (5) is a coil heat exchanger, and the coil is tightly wrapped around the outer wall of the liquid storage tank (6).

3. The refrigerant liquefaction device according to claim 2, characterized in that: The space between the coil and the outer wall of the liquid storage tank (6) is filled with a thermally conductive material.

4. The refrigerant liquefaction device according to claim 1, characterized in that: An adjustable valve is provided at the second outlet (12) of the three-way diverter (3).

5. The refrigerant liquefaction device according to claim 1, characterized in that: The liquid storage tank (6) is a vertical cylindrical structure.

6. The refrigerant liquefaction device according to claim 1, characterized in that: The throttling element (7) is a capillary tube or a thermostatic expansion valve.

7. The refrigerant liquefaction device according to claim 1, characterized in that: The main heat exchanger (5) is a plate heat exchanger.

Images