An evaporator oil collection device and refrigeration unit for purifying high-temperature refrigeration oil
By designing an evaporator oil collection device for high-temperature refrigeration oil purification, the problem of difficult recovery of refrigeration oil in flooded evaporators is solved, achieving efficient oil return and normal operation of the evaporator, and reducing additional configuration costs.
Patent Information
- Application Number
- CN202522630979.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-11
- Publication Date
- 2026-11-06
- Estimated Expiration
- 2035-12-11
AI Technical Summary
In existing technologies, refrigeration oil is difficult to recover efficiently in refrigeration systems, especially in flooded evaporators, leading to problems such as abnormal compressor operation and reduced evaporator heat exchange efficiency.
Design an evaporator oil collection device that uses high-temperature refrigeration oil for purification, including an oil-gas separation chamber, a liquid inlet zone, a purification zone, and an oil storage zone. A float device is used to control the liquid inlet pipe to float at the liquid surface position. Combined with a high-temperature oil pipe, the oil-liquid mixture is purified and recovered. The oil return process is controlled by a solenoid valve.
It achieves efficient recovery of refrigeration oil, improves oil return efficiency, reduces additional configuration costs, ensures normal operation and heat exchange efficiency of the evaporator, and prioritizes cooling capacity when operating conditions change.
Smart Images
Figure CN224945044U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of refrigeration technology, specifically to an evaporator oil collection device and refrigeration unit that utilizes high-temperature refrigeration oil purification. Background Technology
[0002] When refrigeration equipment is running, the refrigerant oil in the compressor is carried out of the compressor by the high-speed flowing gaseous refrigerant and enters the entire refrigerant circulation system. For refrigeration systems using flooded evaporators, because the boiling point of the refrigerant oil is much higher than that of the refrigerant, the refrigerant oil will not evaporate along with the refrigerant after entering the evaporator. If no oil return measures are taken, the refrigerant oil will accumulate inside the evaporator, significantly impacting the normal operation of the compressor and the heat exchange efficiency inside the evaporator. Installing an oil separator between the compressor and condenser can filter out most of the refrigerant oil entrained in the gaseous refrigerant, but the oil separator cannot achieve 100% filtration; a small amount of refrigerant oil will still enter the evaporator. Because the density of refrigeration oil is less than that of liquid refrigerant, the refrigeration oil entering the evaporator mainly concentrates at the liquid refrigerant level and mixes with it. The conventional method for separating the refrigeration oil from the evaporator is to set a liquid sampling port at approximately the liquid level in the evaporator and guide the mixture of refrigerant and refrigeration oil back into the compressor. However, this method is not very efficient in terms of oil return. First, the solution sampled is a mixture of refrigerant and refrigeration oil, and the oil content in the mixture cannot be guaranteed, thus compromising the oil return efficiency. Second, during unit operation, the liquid refrigerant level inside the evaporator varies under different heat exchange conditions. Furthermore, the refrigerant level inside the evaporator constantly fluctuates with the evaporation reaction, causing the sampling port to be too high to collect any liquid, or too low to collect a solution containing only a very small amount of refrigeration oil. Utility Model Content
[0003] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an evaporator oil collection device and refrigeration unit that utilizes high-temperature refrigeration oil for purification. This device can effectively collect the refrigeration oil that enters the evaporator. It can effectively collect the oil-liquid mixture at the liquid refrigerant level in the evaporator, while maximizing the refrigeration oil content in the mixture. The collected oil-liquid mixture can be further purified using the high-temperature refrigeration oil separated by an oil separator, thereby improving oil return efficiency.
[0004] The purpose of this utility model is achieved through the following technical solution: an evaporator oil collection device for purifying high-temperature refrigeration oil, comprising a device shell and an oil-gas separation chamber disposed within the device shell, wherein a heat exchange baffle and a liquid inlet partition plate are fixed inside the oil-gas separation chamber, wherein a liquid inlet area is formed between the liquid inlet partition plate and the inner wall of the oil-gas separation chamber, a purification area is formed between the liquid inlet partition plate and the area above the heat exchange baffle plate, and an oil storage area is formed below the heat exchange baffle plate; A liquid inlet pipe is slidably installed on the outer casing of the device corresponding to the liquid inlet zone, and an exhaust pipe is fixedly installed on the outer casing of the device corresponding to the purification zone. A float device is set between the liquid inlet pipe and the exhaust pipe. This float device is used to float on the liquid surface of the liquid refrigerant in the flooded evaporator, thereby driving the liquid inlet pipe to float up and down in the flooded evaporator. The liquid inlet zone and the purification zone are connected by an intermediate liquid pipe. A high-temperature oil pipe is provided in the purification zone above the heat exchange baffle. Both ends of the high-temperature oil pipe extend out of the gas-oil separation chamber. The purification zone and the oil storage zone are connected by a lower oil port opened on the heat exchange baffle. An oil outlet set at the bottom of the oil storage zone extends out of the gas-oil separation chamber.
[0005] As a further technical solution, the float device includes a float, an L-shaped tie rod installed at the bottom of the float, the other end of the L-shaped tie rod facing the liquid inlet pipe and fixed to the outer wall at the inlet pipe opening, and a float sleeve installed on the side of the float facing the exhaust pipe, the float sleeve slidingly fitted onto the exhaust pipe.
[0006] As a further technical solution, two positioning blocks, one high and one low, are set on the outer wall of the inlet pipe to limit the vertical sliding stroke of the inlet pipe.
[0007] As a further technical solution, the float is located above the liquid inlet of the liquid inlet pipe, and a gap is set between the float and the liquid inlet to ensure that after the liquid inlet pipe is placed into the flooded evaporator, the liquid inlet is always 1-2 cm below the liquid surface of the liquid refrigerant inside the flooded evaporator, so that the oil-liquid mixture in the flooded evaporator enters the liquid inlet area through the liquid inlet.
[0008] As a further technical solution, the inlet of the intermediate liquid pipe is located at the lower part of the inlet area, the outlet of the intermediate liquid pipe passes through the outer shell of the device and is located above the high-temperature oil pipe in the purification area, and the lower oil outlet is located on the side of the heat exchange baffle away from the outlet of the intermediate liquid pipe.
[0009] As a further technical solution, a solenoid valve is installed on the intermediate liquid pipe located outside the housing of the device. When the compressor of the unit where the flooded evaporator is located is running, the solenoid valve remains energized and open, and the solenoid valve controls the opening and closing according to the suction superheat of the unit.
[0010] As a further technical solution, the inlet of the high-temperature oil pipe extends into the purification zone from above the lower oil port, and the outlet of the high-temperature oil pipe extends out of the purification zone from the side where the exhaust pipe is located. The high-temperature refrigeration oil separated by the unit's oil separator exchanges heat with the oil mixture in the purification zone through the high-temperature oil pipe.
[0011] As a further technical solution, the exhaust pipe is set at the top of the purification zone, so that after the exhaust pipe is placed in the flooded evaporator, the outlet of the exhaust pipe is higher than the highest liquid level of the liquid refrigerant inside the flooded evaporator.
[0012] A refrigeration unit includes an evaporator oil collection device, a flooded evaporator, a high-efficiency oil separator, a compressor, a condenser, and several connecting pipes. The evaporator oil collection device A is an evaporator oil collection device that utilizes high-temperature refrigeration oil for purification, as described above. The evaporator oil collection device is installed at the bottom of the flooded evaporator. A high-efficiency oil separator is installed on the connecting pipe between the compressor suction port and the condenser. The high-efficiency oil separator is connected to the high-temperature oil pipe inlet on the evaporator oil collection device through a first oil return pipe, and the high-temperature oil pipe outlet is connected to the compressor through a second oil return pipe, so that the high-temperature refrigeration oil filtered by the high-efficiency oil separator returns to the compressor through the evaporator oil collection device.
[0013] As a further technical solution, the oil outlet of the evaporator oil collection device is connected to the compressor through the evaporator oil return pipeline, and the compressor exhaust port is connected to the condenser through the oil return ejector pipeline. An ejector pump is installed on the oil return ejector pipeline, and the evaporator oil return pipeline and the oil return ejector pipeline are connected after the ejector pump, so that the high-purity liquid refrigeration oil collected in the oil storage area is ejected back into the compressor through the evaporator oil return pipeline.
[0014] The beneficial effects of this utility model are as follows: 1. The oil collection device A inlet of the evaporator can continuously extract oil-liquid mixture, and will not fail to extract liquid due to changes in operating conditions, thus ensuring the continuity of oil return. 2. The collected oil mixture is evaporated and purified using high-temperature refrigeration oil, which further improves the oil return efficiency. The structure is simple, requires no additional materials, and saves costs. 3. For units operating under harsh conditions, the temperature of the refrigeration oil collected by the oil separator is also too high due to the high exhaust temperature. In this case, additional equipment is needed to cool the high-temperature refrigeration oil collected by the oil separator. This evaporator oil collection device can effectively reduce the temperature of the high-temperature refrigeration oil collected by the oil separator while purifying the refrigeration oil collected in the evaporator, thus reducing the cost of additional equipment. 4. When the evaporator's cooling capacity is temporarily insufficient, the evaporator oil collection device can stop collecting liquid by closing the solenoid valve, prioritizing the use of liquid refrigerant to provide cooling capacity, and then restarting it after the situation is relieved. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structure of this utility model.
[0016] Figure 2 This is a three-dimensional structural diagram of the present invention (the outer shell of the device is made transparent for ease of display).
[0017] Figure 3 This is a schematic diagram of the internal area of the gas-oil separation chamber in this utility model.
[0018] Figure 4 This is a schematic diagram of the installation structure of the evaporator oil collection device on a flooded evaporator in this utility model.
[0019] Figure 5 This is a schematic diagram of the float device in this utility model.
[0020] Figure 6 This is a schematic diagram of the heat exchange baffle in this utility model.
[0021] Figure 7 This is a schematic diagram of the piping connection structure of the refrigeration unit in this utility model.
[0022] Explanation of reference numerals in the attached drawings: A. Evaporator oil collection device; B. Flooded evaporator; C. High-efficiency oil separator; D. Compressor; E. Condenser; F1. First oil separator return line; F2. Second oil separator return line; G. Return oil ejector line; G1. Evaporator return line; H. Gas-oil separation chamber; A1. Liquid inlet zone; i. Purification zone; ii. Oil storage zone; iii. Liquid inlet pipe; A2. Positioning block; A21. Float device; A3. Float; A31. L-shaped pull rod; A32. Float sleeve; A33. Exhaust pipe; A4. High-temperature oil pipe; A5. Heat exchange baffle; A6. Lower oil port; A61. Oil outlet; A7. Liquid inlet separator; A8. Intermediate liquid pipe; A9. Solenoid valve; A10. Detailed Implementation
[0023] The present invention will now be described in detail with reference to the accompanying drawings: Example 1: As shown in the attached document Figures 1-6 As shown, an evaporator oil collection device for purifying high-temperature refrigeration oil includes an oil-gas separation chamber A1, a liquid inlet zone i, a purification zone ii, an oil storage zone iii, a liquid inlet pipe A2, a positioning block A21, a float device A3, a float A31, an L-shaped pull rod A32, a float sleeve A33, an exhaust pipe A4, a high-temperature oil pipe A5, a heat exchange baffle A6, a lower oil port A61, an oil outlet A7, a liquid inlet separator A8, an intermediate liquid pipe A9, and a solenoid valve A10.
[0024] Reference Appendix Figure 4 The oil collection device is installed at the bottom of the flooded evaporator B, such as... Figure 1 , 2As shown in Figure 3, the oil collecting device includes a housing (the housing is made transparent for ease of demonstration) and a gas-oil separation chamber A1 located within the housing. An inlet baffle plate A8 (L-shaped cross-section) and a heat exchange baffle plate A6 (circular with a notch) are fixed within the gas-oil separation chamber A1. Figure 3 As shown, an inlet zone i is formed between the liquid inlet partition plate A8 and the inner wall of the gas-oil separation chamber A1, a purification zone ii is formed between the liquid inlet partition plate A8 and the upper part of the heat exchange baffle plate A6, and an oil storage zone iii is formed below the heat exchange baffle plate A6.
[0025] A liquid inlet pipe A2 is slidably installed on the outer casing of the device corresponding to liquid inlet zone i, and an exhaust pipe A4 is fixedly installed on the outer casing of the device corresponding to purification zone ii. A float device A3 is installed between the liquid inlet pipe A2 and the exhaust pipe A4. This float device A3 can float at the liquid refrigerant surface level in the flooded evaporator B, thereby causing the liquid inlet pipe A2 to float up and down within the flooded evaporator B. Further, as... Figure 5 As shown, the float device A3 includes a float A31, an L-shaped pull rod A32 installed at the bottom of the float A31, the other end of the L-shaped pull rod A32 facing the liquid inlet pipe A2 and fixed to the outer wall at the opening of the liquid inlet pipe A2, and a float sleeve A33 installed on the side of the float A31 facing the exhaust pipe A4. The float sleeve A33 is slidably fitted onto the exhaust pipe A4 to fix the float device A3 in the horizontal direction, so that it can only move in the vertical direction, thus avoiding damage to the internal structure of the flooded evaporator B.
[0026] Preferably, such as Figure 1 , 2 As shown, two positioning blocks A21, one higher and one lower, are set on the outer wall of the liquid inlet pipe A2. The positioning blocks A21 can limit the vertical sliding stroke of the liquid inlet pipe A2. Preferably, the float A31 is located above the liquid inlet of the liquid inlet pipe A2, and a certain gap (spacing) is set between the float A31 and the liquid inlet. This gap (spacing) ensures that after the liquid inlet pipe A2 is placed into the flooded evaporator B, the liquid inlet is always 1-2 cm below the liquid refrigerant level inside the flooded evaporator B, so that the oil-liquid mixture in the flooded evaporator B enters the liquid inlet zone i through the liquid inlet.
[0027] Furthermore, the inlet zone i and the purification zone ii are connected by an intermediate liquid pipe A9 (part of which is located outside the device casing, and the other part extends into the purification zone ii). A high-temperature oil pipe A5 is located in the purification zone ii above the heat exchange baffle A6, with both ends of the high-temperature oil pipe A5 exiting the gas-oil separation chamber A1. The purification zone ii and the oil storage zone iii are connected by a lower oil outlet A61 located on the heat exchange baffle A6. An oil outlet A7 located at the bottom of the oil storage zone iii extends out of the gas-oil separation chamber A1. The inlet of the intermediate liquid pipe A9 is located at the lower part of the inlet zone i, and the outlet of the intermediate liquid pipe A9 passes through the device casing and is located above the high-temperature oil pipe A5 in the purification zone ii. The lower oil outlet A61 is located on the side of the heat exchange baffle A6 away from the outlet of the intermediate liquid pipe A9. In addition, a solenoid valve A10 is installed on the intermediate liquid pipe A9 located outside the device casing. When the compressor D of the unit where the flooded evaporator B is located is running, the solenoid valve A10 remains energized and open. The solenoid valve A10 controls the opening and closing according to the suction superheat of the unit. When the suction superheat is greater than T1 (generally 5°C), it closes. When the suction superheat is less than T2 (generally 2°C), the solenoid valve A10 opens again.
[0028] like Figure 2 , 3 As shown, the inlet of high-temperature oil pipe A5 extends into purification zone ii from above the lower oil port A61, and the outlet of high-temperature oil pipe A5 extends out of purification zone ii from the side where exhaust pipe A4 is located. The high-temperature refrigeration oil separated by the unit's oil separator exchanges heat with the oil mixture in purification zone ii through high-temperature oil pipe A5. Exhaust pipe A4 is located at the top of purification zone ii, so that after exhaust pipe A4 is placed in the flooded evaporator B, the outlet of exhaust pipe A4 is higher than the highest liquid level of the liquid refrigerant inside the flooded evaporator B.
[0029] During unit operation, the oil-liquid mixture at the liquid refrigerant level inside evaporator B enters the inlet zone i inside the oil-gas separator A1 through inlet pipe A2, and then enters the purification zone ii through intermediate liquid pipe A9. In purification zone ii, the oil-liquid mixture exchanges heat with the high-temperature refrigeration oil inside high-temperature oil pipe A5. The liquid refrigerant in the oil-liquid mixture absorbs heat and evaporates into gaseous refrigerant, which returns to the flooded evaporator B through exhaust pipe A4. The remaining liquid refrigeration oil enters the oil storage zone iii through the lower oil port A61 of heat exchange baffle A6, and finally returns to the compressor through the oil outlet A7 at the bottom of the oil-gas separator A1.
[0030] During unit operation, a temporary shortage of cooling capacity may occur in the flooded evaporator B due to a lack of liquid refrigerant. In this situation, the suction superheat of the unit will increase. If the evaporator oil collection device A continues to continuously draw oil mixture from the flooded evaporator B, the insufficient cooling capacity will inevitably worsen. To address this issue, a solenoid valve A10 is installed on the intermediate liquid line A9. The solenoid valve A10 remains energized and open during compressor D operation. When the suction superheat exceeds T1 (typically 5°C), it closes, preventing the oil mixture in the flooded evaporator B from entering the evaporator oil collection device A, thus ensuring sufficient liquid refrigerant in the flooded evaporator B to provide cooling capacity. When the suction superheat falls below T2 (typically 2°C), the solenoid valve A10 reopens.
[0031] To further improve the purification efficiency of the evaporator oil collecting device A and ensure more thorough evaporation of the liquid refrigerant in the oil mixture, the following design was adopted: Design 1: The lower oil inlet A61 of the heat exchange baffle A6 is located on the side away from the outlet of the intermediate liquid pipe A9, allowing sufficient heat exchange time between the oil mixture entering purification zone ii and the high-temperature refrigeration oil. 2. The oil outlet of the high-temperature oil pipe A5 is located on the side of the exhaust pipe A4, and the oil inlet of the high-temperature oil pipe A5 is located above the lower oil inlet A61 of the heat exchange baffle A6.
[0032] Example 2: A refrigeration unit, such as Figure 7 As shown, the evaporator oil collection device using high-temperature refrigeration oil purification described in Example 1 is used. This refrigeration unit includes an evaporator oil collection device A, a flooded evaporator B, a high-efficiency oil separator C, a compressor D, a condenser E, and several connecting pipes. The evaporator oil collection device A is installed at the bottom of the flooded evaporator B. The high-efficiency oil separator C is installed on the connecting pipe between the suction port of the compressor D and the condenser E. The high-efficiency oil separator C is connected to the oil inlet of the high-temperature oil pipe A5 on the evaporator oil collection device A through the first oil return pipe F1. The oil outlet of the high-temperature oil pipe A5 is connected to the compressor D through the second oil return pipe F2, so that the high-temperature refrigeration oil filtered by the high-efficiency oil separator C returns to the compressor D through the evaporator oil collection device A.
[0033] Furthermore, the oil outlet A7 of the evaporator oil collection device A is connected to the compressor D through the evaporator oil return line H, and the discharge port of the compressor D is connected to the condenser E through the oil return ejector line G. An ejector pump G1 is installed on the oil return ejector line G. The evaporator oil return line H and the oil return ejector line G are connected after the ejector pump G1, so that the high-purity liquid refrigeration oil collected in the oil storage area iii is ejected back into the compressor D through the evaporator oil return line H.
[0034] The working process of this utility model: When the unit is running, the refrigerant oil in compressor D is carried out of compressor D by the high-speed flowing gaseous refrigerant and enters the entire refrigerant circulation system. Most of the refrigerant oil carried out of compressor D is filtered and separated in oil separator C, and returns to compressor D through the first oil return line F1, high-temperature oil line A5, and the second oil return line F2. A small portion of the refrigerant oil, along with the refrigerant circulation, eventually enters the flooded evaporator B. Because the density of refrigerant oil is less than that of liquid refrigerant, the refrigerant oil entering the evaporator is mainly concentrated at the liquid refrigerant level.
[0035] The evaporator oil collecting device A is equipped with an intermediate liquid pipe A9, which connects the inlet zone i and purification zone ii of the oil-gas separation chamber A1. An electromagnetic valve A10 is mounted on the intermediate liquid pipe A9, which remains energized and open during compressor D operation. It closes when the suction superheat exceeds T1 (typically 5°C), preventing the oil-liquid mixture in the flooded evaporator B from entering the evaporator oil collecting device A, thus ensuring sufficient liquid refrigerant in the flooded evaporator B to provide cooling capacity. When the suction superheat falls below T2 (typically 2°C), the electromagnetic valve A10 reopens. The float device A3 on the evaporator oil collecting device A always floats at the liquid refrigerant level due to buoyancy. When the electromagnetic valve A10 is open, the inlet of the liquid inlet pipe A2 is driven by the float device A3, maintaining it at a position close to the liquid level. Here, the oil-liquid mixture with a high oil content continuously enters the inlet zone i of the oil-gas separation chamber A1 through the liquid inlet pipe A2. The oil mixture then enters purification zone ii via intermediate liquid pipe A9, where it exchanges heat with the high-temperature refrigeration oil in high-temperature oil pipe A5. A heat exchange baffle A6 is installed below high-temperature oil pipe A5 to extend the heat exchange time. In purification zone ii, the liquid refrigerant in the oil mixture absorbs heat and evaporates into a gaseous state, returning to the flooded evaporator B through the exhaust pipe A4 located above the evaporator oil collecting device A. The liquid refrigeration oil, on the other hand, enters the oil storage zone iii of the gas-oil separation chamber A1 through the lower oil port A61 on the heat exchange baffle A6. Conversely, the high-temperature refrigeration oil in high-temperature oil pipe A5 releases heat, achieving effective cooling.
[0036] An oil outlet A7 is provided on the bottom plate of the gas-oil separation chamber A1. The connecting pipe between the oil outlet A7 and the compressor D is the evaporator oil return pipe H. The connecting pipe between the condenser E and the compressor D is the oil return ejector pipe G. Under the drive of the high and low pressure difference of the system, the gaseous refrigerant in the condenser E flows spontaneously from the condenser E to the compressor D. An ejector pump G1 is provided in the oil return ejector pipe G. When the gaseous refrigerant flows through the ejector pump G1, the flow velocity increases rapidly. The evaporator oil return pipe H and the oil return ejector pipe G are connected after the ejector pump G1. Relying on the negative pressure generated around the high-speed fluid, the high-purity liquid refrigeration oil collected in the oil storage area iii is ejected back into the compressor D through the evaporator oil return pipe H.
[0037] It is understood that, for those skilled in the art, any equivalent substitutions or modifications to the technical solutions and inventive concepts of this utility model should fall within the protection scope of the appended claims.
Claims
1. An evaporator oil collection device for purifying high-temperature refrigeration oil, installed at the bottom of a flooded evaporator (B), characterized in that: The device includes a housing and a gas-oil separation chamber (A1) disposed within the housing. A heat exchange baffle (A6) and a liquid inlet partition plate (A8) are fixed inside the gas-oil separation chamber (A1). A liquid inlet zone (i) is formed between the liquid inlet partition plate (A8) and the inner wall of the gas-oil separation chamber (A1). A purification zone (ii) is formed between the liquid inlet partition plate (A8) and the area above the heat exchange baffle plate (A6). An oil storage zone (iii) is formed below the heat exchange baffle plate (A6). A liquid inlet pipe (A2) is slidably installed on the outer casing of the device corresponding to the liquid inlet zone (i), and an exhaust pipe (A4) is fixedly installed on the outer casing of the device corresponding to the purification zone (ii). A float device (A3) is installed between the liquid inlet pipe (A2) and the exhaust pipe (A4). This float device (A3) is used to float on the liquid refrigerant surface in the flooded evaporator (B), thereby causing the liquid inlet pipe (A2) to float up and down in the flooded evaporator (B). i) is connected to the purification zone (ii) through an intermediate liquid pipe (A9). A high-temperature oil pipe (A5) is provided in the purification zone (ii) above the heat exchange baffle (A6). Both ends of the high-temperature oil pipe (A5) extend out of the gas-oil separation chamber (A1). The purification zone (ii) is connected to the oil storage zone (iii) through an oil outlet (A61) opened on the heat exchange baffle (A6). An oil outlet (A7) set at the bottom of the oil storage zone (iii) extends out of the gas-oil separation chamber (A1).
2. The evaporator oil collection device for purifying high-temperature refrigeration oil according to claim 1, characterized in that: The float device (A3) includes a float (A31), an L-shaped pull rod (A32) installed at the bottom of the float (A31), the other end of the L-shaped pull rod (A32) facing the inlet pipe (A2) and fixed to the outer wall at the inlet of the inlet pipe (A2), and a float sleeve (A33) installed on the side of the float (A31) facing the exhaust pipe (A4), and the float sleeve (A33) is slidably fitted onto the exhaust pipe (A4).
3. The evaporator oil collection device for purifying high-temperature refrigeration oil according to claim 2, characterized in that: Two positioning blocks (A21) are set at different heights on the outer wall of the inlet pipe (A2) to limit the vertical sliding stroke of the inlet pipe (A2).
4. The evaporator oil collection device for purifying high-temperature refrigeration oil according to claim 2, characterized in that: The float (A31) is located above the liquid inlet of the liquid inlet pipe (A2), and a gap is provided between the float (A31) and the liquid inlet to ensure that after the liquid inlet pipe (A2) is placed into the flooded evaporator (B), the liquid inlet is always 1-2 cm below the liquid surface of the liquid refrigerant inside the flooded evaporator (B), so that the oil-liquid mixture in the flooded evaporator (B) enters the liquid inlet area (i) through the liquid inlet.
5. The evaporator oil collection device for purifying high-temperature refrigeration oil according to claim 1, characterized in that: The inlet of the intermediate liquid pipe (A9) is located at the lower part of the inlet area (i), the outlet of the intermediate liquid pipe (A9) passes through the outer shell of the device and is located above the high-temperature oil pipe (A5) in the purification area (ii), and the lower oil port (A61) is located on the side of the heat exchange baffle (A6) away from the outlet of the intermediate liquid pipe (A9).
6. The evaporator oil collection device for purifying high-temperature refrigeration oil according to claim 5, characterized in that: A solenoid valve (A10) is installed on the intermediate liquid pipe (A9) located outside the housing of the device. When the compressor (D) of the unit where the flooded evaporator (B) is located is running, the solenoid valve (A10) remains energized and open, and the solenoid valve (A10) controls the opening and closing according to the suction superheat of the unit.
7. The evaporator oil collection device for purifying high-temperature refrigeration oil according to claim 6, characterized in that: The inlet of the high-temperature oil pipe (A5) extends into the purification zone (ii) from above the lower oil port (A61), and the outlet of the high-temperature oil pipe (A5) extends out of the purification zone (ii) from the side where the exhaust pipe (A4) is located. The high-temperature refrigeration oil separated by the unit oil separator exchanges heat with the oil mixture in the purification zone (ii) through the high-temperature oil pipe (A5).
8. The evaporator oil collection device for purifying high-temperature refrigeration oil according to claim 1, characterized in that: The exhaust pipe (A4) is located at the top of the purification zone (ii). After the exhaust pipe (A4) is placed into the flooded evaporator (B), the outlet of the exhaust pipe (A4) is higher than the highest liquid level of the liquid refrigerant inside the flooded evaporator (B).
9. A refrigeration unit, comprising an evaporator oil collecting device (A), a flooded evaporator (B), a high-efficiency oil separator (C), a compressor (D), a condenser (E), and a plurality of connecting pipes, wherein the evaporator oil collecting device A is an evaporator oil collecting device using high-temperature refrigeration oil purification as described in any one of claims 1 to 8, characterized in that: The evaporator oil collection device (A) is installed at the bottom of the flooded evaporator (B). A high-efficiency oil separator (C) is installed on the connecting pipe between the compressor (D) suction port and the condenser (E). The high-efficiency oil separator (C) is connected to the oil inlet of the high-temperature oil pipe (A5) on the evaporator oil collection device (A) through the first oil return pipe (F1). The oil outlet of the high-temperature oil pipe (A5) is connected to the compressor (D) through the second oil return pipe (F2), so that the high-temperature refrigeration oil filtered by the high-efficiency oil separator (C) returns to the compressor (D) through the evaporator oil collection device (A).
10. The refrigeration unit according to claim 9, characterized in that: The oil outlet (A7) of the evaporator oil collection device (A) is connected to the compressor (D) through the evaporator oil return line (H). The exhaust port of the compressor (D) is connected to the condenser (E) through the oil return ejector line (G). An ejector pump (G1) is installed on the oil return ejector line (G). The evaporator oil return line (H) and the oil return ejector line (G) are connected after the ejector pump (G1), so that the high-purity liquid refrigeration oil collected in the oil storage area (iii) is ejected back into the compressor (D) through the evaporator oil return line (H).