Horizontal oil separator, separation method and refrigeration system

Abstract

This application provides a horizontal oil separation device, separation method, and refrigeration system, belonging to the technical field of refrigeration systems. The horizontal oil separation device includes a shell, several storage tanks, several static pressure sensors, an oil storage chamber, a liquid inlet pipe, and a control module. The static pressure sensors are associated with the drain valves of the storage tanks. The control module is electrically connected to the static pressure sensors, drain valves, oil drain valves, oil return valves, and separation valves. When the static pressure detected by the static pressure sensor exceeds a preset static pressure value, the drain valve is opened and then delayed in closing. This application uses multiple storage tanks, each equipped with a static pressure sensor. By linking the static pressure sensors with the drain valves, the refrigerant and lubricating oil are continuously separated and concentrated, thereby increasing the concentration of the lubricating oil and ensuring that the refrigerant liquid discharged from each storage tank is free of lubricating oil, thus ensuring stable operation of the draining and oil discharge process.

Description

Technical Field

[0001] This application belongs to the field of refrigeration system technology, specifically, it relates to a horizontal oil separation device, separation method and refrigeration system for separating refrigerant and lubricating oil. Background Technology

[0002] In refrigeration systems, compressors typically use lubricating oil for lubrication and sealing of reciprocating mechanisms. At high temperatures, the lubricating oil, in the form of an oil mist, is discharged from the compressor along with the refrigerant gas in a gaseous mixture. Although the compressor performs oil-gas separation during exhaust, it cannot completely separate the lubricating oil from the gaseous mixture. Therefore, the refrigerant gas containing the atomized lubricating oil will condense into liquid refrigerant and lubricating oil upon entering the condenser. If the lubricating oil enters the evaporator of the refrigeration system along with the refrigerant and adheres to the heat transfer interface, it will reduce the evaporator's heat transfer efficiency. Furthermore, if the lubricating oil cannot be recovered, it will result in oil loss and increase the cost of lubricating oil consumption.

[0003] In existing technologies, for ammonia removal refrigeration systems, since the density of lubricating oil is greater than that of liquid ammonia, the lubricating oil will sink to the bottom of the liquid ammonia. Therefore, it is only necessary to periodically drain the lubricating oil from the bottom to separate the lubricating oil from the liquid ammonia.

[0004] However, for refrigeration systems using chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs), the density of the lubricating oil is usually less than that of the liquid refrigerant. This means the refrigerant settles at the bottom of the lubricating oil. Therefore, unlike ammonia-removing refrigeration systems, the lubricating oil cannot be directly discharged from the bottom. Furthermore, a layer of foam easily forms at the interface between the liquid CFC or HCFC refrigerant and the lubricating oil. This foam floats on top of the refrigerant and overflows to the bottom with the liquid, hindering the return of the lubricating oil to the refrigeration compressor. If a liquid level detection system is installed, it also interferes with the detection process. This makes it difficult to separate the lubricating oil from the liquid CFC or HCFC refrigerant in the condenser.

[0005] Improving the separation efficiency of the oil separator is one way to prevent lubricating oil from entering the evaporator of the refrigeration system along with the refrigerant. However, even with a high oil separation efficiency, it is impossible to achieve 100%. Therefore, further separation of refrigerant liquid and lubricating oil is necessary in the refrigeration system. Summary of the Invention

[0006] In view of the problem that lubricating oil in chlorofluorocarbon or hydrochlorofluorocarbon refrigerant liquids is difficult to effectively separate from the refrigerant in existing refrigeration systems, this application aims to provide a horizontal oil separation device, separation method and refrigeration system, which effectively separates lubricating oil from the refrigerant mixture by continuously separating the refrigerant and lubricating oil into layers.

[0007] In a first aspect, this application provides a horizontal oil separator, comprising:

[0008] The housing includes a horizontal cylindrical body with chambers and caps located at both ends of the horizontal cylindrical body;

[0009] Several storage tanks are arranged horizontally on the bottom of the horizontal cylinder in order of height. Each storage tank has a drain pipe at the bottom that flows to the main outlet pipe, and each drain pipe is provided with a drain switch valve and a drain check valve in the direction of outflow.

[0010] A plurality of static pressure sensors are provided, each corresponding to one of the plurality of storage tanks, and each static pressure sensor is installed at the same horizontal height on the corresponding drain pipe. The static pressure sensors are associated with the drain switch valve of the corresponding storage tank.

[0011] The inlet pipe is used to deliver the mixed liquid to be separated into the storage tank at the highest side of the storage tank.

[0012] An oil storage chamber is formed at the bottom of the chamber on the side with the lowest height of the storage tank. The bottom of the shell is provided with an oil drain pipe that connects to the oil storage chamber. An oil drain switch valve is provided in the outflow direction of the oil drain pipe. One outlet of the oil drain switch valve is connected to a return oil switch valve, and the other outlet is provided with a separation switch valve and a separation check valve in sequence and connected to the uppermost storage tank.

[0013] The control module is electrically connected to each static pressure sensor, drain valve, oil drain valve, return valve, and disconnect valve. The control module is used for:

[0014] The mixed liquids to be separated are fed into the storage tank at the highest point of the storage tank.

[0015] When the static pressure detected by the static pressure sensor in each storage tank is greater than the preset static pressure value, the corresponding storage tank's drain valve is opened and then closed after a delay.

[0016] When the separation state of the oil storage chamber meets the preset oil return requirements, the control valves for the oil drain and return are opened, and the separation valve is closed; otherwise, the control valves for the oil drain and separation are opened, and the oil drain valve is closed.

[0017] In one possible embodiment, the static pressure preset values ​​of the plurality of static pressure sensors decrease sequentially as the height of the storage tank decreases.

[0018] In one possible embodiment, four storage tanks are provided;

[0019] Accordingly, the static pressure preset values ​​of the four static pressure sensors, from high to low, are as follows:

[0020] The static pressure sensor is installed at the top edge of the storage tank, where 30% of the lubricating oil and 70% of the refrigerant are stored to generate static pressure.

[0021] The static pressure sensor is installed at the top edge of the storage tank, where 50% of the lubricating oil and 50% of the refrigerant are stored to generate static pressure.

[0022] The static pressure sensor is installed at the top edge of the storage tank, where 70% of the lubricating oil and 30% of the refrigerant are stored to generate static pressure.

[0023] The static pressure sensor is installed at the horizontal line to the upper edge of the storage tank, storing the static pressure generated by 85% lubricating oil and 15% refrigerant.

[0024] In one possible embodiment, it further includes:

[0025] An exhaust pipe is located above the housing.

[0026] In one possible embodiment, the upper part of the oil storage chamber is separated by a concave sealing cover, the bottom of the concave sealing cover is connected to the oil storage chamber, and an oil drain check valve is provided at the connection point. An air inlet pipe is provided at the upper part of the oil storage chamber.

[0027] In one possible embodiment, the plurality of storage tanks are vertically separated by an arc-shaped partition.

[0028] In one possible embodiment, the upper edge of the bow-shaped partition is provided with a serrated notch.

[0029] In one possible embodiment, an ultrasonic generator is provided on one side of the deepest arc-shaped partition plate of the storage tank, the ultrasonic generator being capable of generating a horizontal planar sound beam.

[0030] Secondly, this application also provides a lubricating oil separation method, applied to the control module of the horizontal oil separation device described in any embodiment of the first aspect, the method comprising:

[0031] The mixed liquids to be separated are fed into the storage tank at the highest point of the storage tank.

[0032] When the static pressure detected by the static pressure sensor in each storage tank is greater than the preset static pressure value, the corresponding storage tank's drain valve is opened and then closed after a delay.

[0033] When the separation state of the oil storage chamber meets the preset oil return requirements, the control valves for the oil drain and return are opened, and the separation valve is closed; otherwise, the control valves for the oil drain and separation are opened, and the oil drain valve is closed.

[0034] Thirdly, this application also provides a refrigeration system, including the horizontal oil separator described in any embodiment of the first aspect.

[0035] This application provides a horizontal oil separation device, separation method, and refrigeration system. The horizontal oil separation device is equipped with several storage tanks with progressively decreasing heights. By continuously separating and concentrating the refrigerant and lubricating oil, the concentration of the lubricating oil is increased, thereby separating the refrigerant and lubricating oil. At the same time, a static pressure sensor is used in conjunction with a drain valve to ensure that the refrigerant liquid discharged from each storage tank is free of lubricating oil. The static pressure sensor of each storage tank is set with a static pressure preset value to ensure stable operation of the drain and oil discharge. Attached Figure Description

[0036] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0037] Figure 1 This is a schematic diagram illustrating an application scenario of a refrigeration system according to this application;

[0038] Figure 2 A schematic diagram of a horizontal oil separator provided in an embodiment of this application;

[0039] Figure 3 This is a schematic diagram of the bow-shaped partition structure provided in an embodiment of this application;

[0040] Figure 4 This is a schematic diagram of another horizontal oil separator provided in an embodiment of this application.

[0041] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments.

[0042] Explanation of reference numerals in the attached figures:

[0043] 101-Compressor; 102-Condenser; 103-Throttling element; 104-Evaporator; 201-Shell; 202-First storage tank; 203-Second storage tank; 204-Third storage tank; 205-Fourth storage tank; 206-Drain pipe; 207-Static pressure sensor; 208-Oil storage chamber; 209-Inlet pipe; 210-Return pipe; 211-Sight glass; 212-Arch-shaped partition plate; 213-Outlet pipe; 214-Serrated notch; 215-Concave sealing cover; 216-Inlet pipe. Detailed Implementation

[0044] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0045] In the embodiments of this application, the terms "first" and "second" are used to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that the terms "first" and "second" do not necessarily imply that they are different.

[0046] It should be noted that in the embodiments of this application, the words "exemplary" or "for example" are used to indicate examples, illustrations, or explanations. Any embodiment or design scheme described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design schemes. Specifically, the use of the words "exemplary" or "for example" is intended to present the relevant concepts in a specific manner. In the embodiments of this application, "at least one" refers to one or more, and "more than one" refers to two or more.

[0047] It should be noted that "at the time of..." in the embodiments of this application can be either at the instant when a certain situation occurs, or for a period of time after the occurrence of a certain situation. The embodiments of this application do not make specific limitations on this.

[0048] Figure 1 This is a schematic diagram illustrating an application scenario of a refrigeration system according to this application. In this application scenario, the refrigeration system mainly includes a compressor 101, a condenser 102, a throttling element 103, and an evaporator 104. The main functions of each part are as follows:

[0049] Compressor: Compressor 101 is the core component of the refrigeration system. Its function is to compress low-temperature, low-pressure gas into high-temperature, high-pressure gas. After the motor is energized, it drives the compression section to work, drawing in low-temperature, low-pressure refrigerant gas, which is then compressed into high-temperature, high-pressure gas.

[0050] Condenser: Condenser 102 is a heat output device that discharges the heat absorbed by the refrigerant in the evaporator and the heat converted from the work consumed by the compressor to the cooling medium (such as water or air), so that the refrigerant changes from a gaseous state to a liquid state.

[0051] Throttling element: Throttling element 103 throttles and reduces the pressure of the refrigerant, regulates the refrigerant flow into the evaporator, and causes the high-pressure, room-temperature refrigerant liquid to be throttled and reduced in pressure when flowing through the expansion valve, turning into low-temperature, low-pressure refrigerant wet vapor, which then enters the evaporator to vaporize and absorb heat, thereby achieving the purpose of cooling.

[0052] Evaporator: Evaporator 104 is the device that outputs cooling capacity. The refrigerant absorbs heat from the object being cooled in the evaporator, thereby achieving the purpose of cooling. In order to ensure that the evaporation process can proceed stably and continuously, the evaporated gas must be continuously extracted by the refrigeration compressor to maintain a certain evaporation pressure.

[0053] exist Figure 1 In the refrigeration system shown, the compressor 101 primarily uses lubricating oil for lubrication and sealing of its reciprocating mechanism. At high temperatures, the lubricating oil, in the form of oil mist, is discharged from the compressor 101 along with the refrigerant gas in a gaseous mixture. Although the compressor 101 performs oil-gas separation in the exhaust, it cannot completely separate the lubricating oil from the gaseous mixture. Therefore, the refrigerant gas containing the atomized lubricating oil is condensed into liquid refrigerant and lubricating oil after entering the condenser 102. If the lubricating oil enters the evaporator 104 of the refrigeration system along with the refrigerant and is adsorbed on the heat transfer interface, it will reduce the heat transfer efficiency of the evaporator 104. In addition, if the lubricating oil cannot be recovered, it will also result in lubricating oil loss, increasing the cost of lubricating oil consumption.

[0054] In existing technologies, for ammonia removal refrigeration systems, because the density of lubricating oil is greater than that of liquid ammonia, the lubricating oil will settle at the bottom of the liquid ammonia. Therefore, simply draining the lubricating oil from the bottom periodically is sufficient to separate the lubricating oil from the liquid ammonia. However, for refrigeration systems using chlorofluorocarbons (CFCs) or hydrochlorofluorocarbons (HCFCs), the density of the lubricating oil is usually less than that of the liquid refrigerant. This means that the refrigerant settles at the bottom of the lubricating oil. Therefore, unlike ammonia removal refrigeration systems, the lubricating oil cannot be directly drained from the bottom. Furthermore, a layer of foam easily forms at the interface between the liquid CFC or HCFC refrigerant and the lubricating oil. This foam floats on top of the refrigerant and overflows to the bottom with the liquid, hindering the return of the lubricating oil to the refrigeration compressor. If a liquid level detection system is installed, it also interferes with the detection. This makes it difficult to separate the lubricating oil from the liquid CFC or HCFC refrigerant in the condenser 102.

[0055] To address the aforementioned issues, this application provides a horizontal oil separation device, a separation method, and a refrigeration system. The horizontal oil separation device comprises several storage tanks with progressively decreasing heights. By continuously separating and concentrating the refrigerant and lubricating oil into layers, the concentration of the lubricating oil is increased, thereby separating the refrigerant and lubricating oil. Simultaneously, a static pressure sensor is used in conjunction with a drain valve to ensure that the refrigerant liquid discharged from each storage tank is free of lubricating oil. The static pressure sensor of each storage tank is set with a preset static pressure value to ensure stable operation of the draining and oil discharge processes.

[0056] Figure 2 This is a schematic diagram of a horizontal oil separator provided in an embodiment of this application. Figure 2 As shown, the horizontal oil separation device provided in this embodiment is applied to a high-pressure refrigeration system, including a housing 201, several storage tanks 202-205, several static pressure sensors 207, an oil storage chamber 208, an inlet pipe 209, and a control module.

[0057] In this embodiment of the application, the housing 201 includes a horizontal cylindrical body with a cavity and a cover located at the upper and lower ends of the horizontal cylindrical body.

[0058] In one specific embodiment, the horizontal cylindrical body is cylindrical, and the cover is designed as an elliptical structure, which can improve the pressure-bearing capacity of the shell 201 compared to a hemispherical structure. Specifically, the cover is an elliptical structure with its major axis extending laterally. In this embodiment, the ratio of the lateral length of the shell 201 to the vertical height of the shell 201 is preferably 2:1 to 5:1.

[0059] In another specific embodiment, the cross-section of the horizontal cylinder is elliptical, in which case the major axis of the cover can make the cover an elliptical structure whether it is in the horizontal or vertical direction.

[0060] In this embodiment of the application, several storage tanks are arranged horizontally on the bottom of the horizontal cylinder in order of height. Each storage tank has a drain pipe at the bottom that flows to the main outlet pipe, and each drain pipe has a drain switch valve and a drain check valve arranged in the outflow direction.

[0061] by Figure 2 For example, the height of several storage tanks decreases sequentially from right to left. The inlet pipe 209 is located on the upper right side of the housing and is used to send the mixed liquid to be separated into the storage tank with the largest height. Specifically, this embodiment of the application is applied to a high-pressure system, where the inlet pipe 209 receives a high-pressure mixed liquid containing lubricating oil and refrigerant.

[0062] In this embodiment, each storage tank 202-205 is formed by a vertically arranged arc-shaped partition plate 212, with the upper part of the storage tank being open, wherein the curved part of the arc-shaped partition plate 212 is closely attached to the bottom inner wall of the shell 201.

[0063] In one specific embodiment, the storage tanks are designated as a first storage tank 202, a second storage tank 203, a third storage tank 204, and a fourth storage tank 205 from right to left. The liquid storage heights of the four storage tanks 202-205 from right to left are H1, H2, H3, and H4, respectively. For the above embodiment, the volumes of the four storage tanks 202-205 from right to left are V1, V2, V3, and V4, respectively. Preferably, the volumes of the four storage tanks 202-205 decrease sequentially from right to left, i.e., V1 > V2 > V3 > V4.

[0064] Each storage tank is equipped with a sight glass 211 at the same height as the upper edge, namely S1, S2, S3 and S4. The liquid level of each independent storage tank can be observed through the sight glass 211 to see whether it exceeds the upper edge.

[0065] The liquid height difference between two adjacent storage tanks is H, which is preferably 50mm to 100mm. The dimension between the arc-shaped partition plate 212 and the upper part of the shell should allow for the smooth passage of the maximum amount of overflow liquid.

[0066] Each storage tank is equipped with drain valves F1, F2, F3, and F4, and each storage tank is equipped with check valves Z1, Z2, Z3, and Z4. The drain valves are installed on the drain pipe 206 of the storage tank, and the check valves are used to prevent the discharged refrigerant from flowing back into the storage tank.

[0067] In this embodiment, a plurality of static pressure sensors 207 correspond one-to-one with a plurality of storage tanks, and each static pressure sensor 207 is installed at the same horizontal height on the corresponding drain pipe 206. The static pressure sensor 207 is associated with the drain switch valve of the corresponding storage tank.

[0068] In the above embodiment, since the static pressure sensor 207 corresponds one-to-one with the storage tank, in this embodiment, static pressure sensors 207 are respectively installed at the same horizontal height from right to left on the drain pipes of the four storage tanks, corresponding to P1, P2, P3, and P4 respectively. Each static pressure sensor 207 has a corresponding static pressure preset value. When the static pressure sensor 207 detects that the liquid pressure in the storage tank reaches the static pressure preset value, it triggers the drain valve of the corresponding storage tank to open and then closes after a delay.

[0069] Preferably, the static pressure preset values ​​corresponding to the static pressure sensors P1, P2, P3, and P4 decrease sequentially from left to right.

[0070] In the above embodiment, assuming the density of the refrigerant is ω1 and the density of the lubricating oil is ω2, for any storage tank, the pressure value detected by the static pressure sensor 207 is:

[0071] W = ω1·g·H1 + ω2·g·(H-H1)

[0072] In the above formula, g is the acceleration due to gravity, H is the total height of the liquid, H1 is the liquid height of the refrigerant, and therefore H-H1 is the liquid height of the lubricating oil.

[0073] After conversion, the pressure value detected by the static pressure sensor 207 is:

[0074] W=(ω1-ω2)·g·H1+ω2·g·H

[0075] Since this application addresses the separation problem where the density of lubricating oil ω2 is less than the density of refrigerant ω1, ω1-ω2>0. Therefore, the pressure value W detected by the static pressure sensor 207 is an increasing function of H1. In other words, the larger the proportion of refrigerant, the larger W becomes.

[0076] In the high-pressure system of this application embodiment, a high-pressure mixture of refrigerant and lubricating oil enters the housing 201 through the inlet pipe 209. When the high-pressure mixture enters the oil separation device of this application, it first enters the storage tank. The refrigerant is located at the bottom of the liquid, and the lubricating oil is located at the top. As the mixture increases, more and more refrigerant deposits at the bottom, while the lubricating oil overflows from the bow-shaped partition plate 212 into the adjacent storage tank at a lower height. Therefore, the proportion of refrigerant in the original storage tank gradually increases. As can be seen from the pressure value W calculated above, as the mixture continuously enters the storage tank, the higher the proportion of refrigerant, the more the pressure value W gradually increases.

[0077] It is clear that the upper limit of the pressure value is when the reservoir is 100% refrigerant, and the lower limit is when the reservoir is 100% lubricating oil. Therefore, the static pressure preset value of the static pressure sensor 207 should be lubricating oil in proportion P and refrigerant in proportion 1-P.

[0078] As the refrigerant deposits from right to left, less and less refrigerant enters the next storage tank. Therefore, the static pressure preset value of the static pressure sensor 207 should have a decreasing trend. This ensures that the pressure value detected by the static pressure sensor 207 is more likely to reach the static pressure preset value in the lower storage tank, thereby triggering the opening of the drain valve.

[0079] In one specific embodiment, the static pressure preset values ​​of the four static pressure sensors 207, from right to left, are as follows:

[0080] Static pressure sensor P1: Its static pressure preset value is the static pressure generated by storing 30% (volume ratio, the same below) lubricating oil and 70% (volume ratio, the same below) refrigerant on the horizontal line of the static pressure sensor P1 installed on the upper edge of the storage tank.

[0081] Static pressure sensor P2: Its static pressure preset value is the static pressure generated by storing 50% lubricating oil and 50% refrigerant on the upper edge of the storage tank when the static pressure sensor P2 is installed on the horizontal line.

[0082] Static pressure sensor P3: Its static pressure preset value is the static pressure generated by storing 70% lubricating oil and 30% refrigerant on the upper edge of the storage tank when the static pressure sensor P3 is installed on the horizontal line.

[0083] Static pressure sensor P4: Its static pressure preset value is the static pressure generated by storing 85% lubricating oil and 15% refrigerant by installing the static pressure sensor P4 with the horizontal line to the upper edge of the storage tank.

[0084] As can be seen from the above static pressure preset value settings, as the refrigerant ratio decreases, the corresponding static pressure preset value gradually decreases, which is consistent with the above analysis on the relationship between static pressure preset value and refrigerant ratio.

[0085] It is clear that for other numbers of static pressure sensors 207, the static pressure preset value of the static pressure sensor 207 can be adjusted according to the specific situation.

[0086] When setting the static pressure preset value, the static pressure preset value of the static pressure sensor 207 is equal to the density at near the refrigerant saturation temperature × gravitational acceleration × (the vertical height difference between the installation horizontal line of the static pressure sensor 207 and the upper edge of the corresponding storage tank - adjustment height).

[0087] It should be further clarified that the static pressure preset value of each static pressure sensor 207 is only a relative value with the same reference, not the actual static pressure. Therefore, the density of the liquid (such as refrigerant) does not need to be the actual saturation temperature, but can be a value close to the actual saturation temperature. This is because the saturation temperature of the refrigerant fluctuates during actual operation of the refrigeration system and is not a fixed value. In principle, the static pressure preset value of each static pressure sensor 207 should be less than the actual static pressure value at that static pressure sensor 207. This is also the reason why an adjustment height must be subtracted from the height when determining the static pressure preset value of each static pressure sensor 207, and this adjustment height value must be a positive number.

[0088] In this embodiment, the oil storage chamber 208 is formed at the bottom of the chamber on the side with the lowest height of the storage tank, so as to... Figure 2 For example, the oil storage chamber 208 is located at the bottom left side of the shell. The bottom of the oil storage chamber 208 is provided with an oil drain pipe. The oil drain pipe is provided with an oil drain switch valve F5 in the outflow direction. One outlet of the oil drain switch valve F5 is connected to the return oil switch valve F6, and the other outlet is provided with a separation switch valve F7 and a separation check valve Z5 in sequence and connected to the first storage tank 202 on the right side.

[0089] In the above embodiment, when the pressure value detected by the static pressure sensor 207 in the storage tank reaches the preset static pressure value, the drain valve is triggered to open, allowing the refrigerant at the bottom to be discharged into the main outlet pipe. After the refrigerant is separated, more and more lubricating oil will enter the next storage tank. After the lubricating oil overflows into the oil storage chamber 208 multiple times, it can be discharged by opening the drain valve F5. Since the lubricating oil still contains a certain amount of refrigerant, when the quality of the lubricating oil does not meet the requirements, the discharged lubricating oil needs to be returned to the first storage tank 202 on the right side through the return pipe 210. It should be noted that the inlet of the return pipe 210 into the first storage tank 202 is preferably located above the upper edge of the first storage tank 202.

[0090] In the embodiments of this application, the control module is electrically connected to static pressure sensors P1, P2, P3, and P4, drain valves F1, F2, F3, and F4, oil drain valve F5, oil return valve F6, and separation valve F7, respectively.

[0091] The control module is used to implement the following control processes:

[0092] S100: The mixed liquid to be separated is fed into the storage tank on the side with the highest height.

[0093] In high-pressure systems, the mixed liquid to be separated is a mixture containing refrigerant and lubricating oil, wherein the refrigerant is a chlorofluorocarbon or hydrochlorofluorocarbon refrigerant with a density greater than that of lubricating oil.

[0094] S200: When the static pressure detected by the static pressure sensor 207 in each storage tank is greater than the static pressure preset value, the corresponding storage tank's drain valve is controlled to open and then close after a delay.

[0095] When the static pressure detected by the static pressure sensor 207 is greater than the static pressure preset value, it indicates that there is a sufficient proportion of refrigerant stored in the storage tank, and the drain valve needs to be opened to discharge it; while delaying the closing ensures that the refrigerant can be continuously discharged for a certain period of time.

[0096] S300: When the separation state of the oil storage chamber 208 meets the preset oil return requirements, control the oil drain valve switch and the oil return switch valve to open, and the separation switch valve to close; otherwise, control the oil drain valve switch and the separation switch valve to open, and the oil drain valve to close.

[0097] The separation state of the oil storage chamber 208 can be observed through the sight glass, or determined based on the depth and pressure value of the oil storage chamber 208.

[0098] Continue reading Figure 2 As shown in the embodiments of this application, the horizontal oil separator can also be improved as follows.

[0099] In one specific embodiment, the liquid inlet pipe 209 enters from directly above the housing 201 and then bends towards the right side of the cover, so that the outlet of the liquid inlet pipe 209 is set towards the inner wall of the housing 201, which can reduce the impact of liquid.

[0100] In another specific embodiment, Figure 3 This is a schematic diagram of the arc-shaped partition structure provided in the embodiments of this application, as shown below. Figure 3 As shown, the upper edge of the arc-shaped partition plate 212 is provided with a serrated notch 214. This allows the serrated notch 214 to defoam the refrigerant as it overflows from top to bottom into the storage tank. The included angle γ of the serrated notch 214 is preferably 60° to 120°, more preferably γ = 90°. The height h of the serrated notch 214 is preferably 20mm to 30mm.

[0101] In another specific embodiment, see below. Figure 2 An ultrasonic generator is installed on one side of the arc-shaped partition plate 212 of the first storage tank 202, which is the deepest part of the tank. The ultrasonic generator can generate a horizontal planar sound beam that can cover the entire liquid surface of the first storage tank 202. The planar sound beam generated by the ultrasonic generator can break up the foam generated on the surface of the refrigerant liquid.

[0102] The following is about Figure 2 The separation process of the horizontal oil separator shown in the embodiment will be described as follows:

[0103] The high-pressure mixed liquid enters from above the first storage tank 202, then bends towards the cover of the housing 201. After collision, change of flow direction, and reduction of flow velocity, the refrigerant liquid and lubricating oil drip into the first storage tank 202, and the liquid level in the first storage tank 202 gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 7:3, the static pressure sensor P1 sends a signal to the drain switch valve F1. The drain switch valve F1 opens and closes after a delay. The refrigerant at the bottom of the first storage tank 202 flows to the liquid outlet manifold through the drain switch valve F1 and the drain check valve Z1. When the static pressure sensor P1 detects that the static pressure is less than the corresponding static pressure preset value, the drain switch valve F1 stops opening, and the liquid level continues to rise. When the liquid level is higher than the upper edge of the first storage tank 202, the lubricating oil or the mixture of lubricating oil and refrigerant overflows from the arc-shaped partition plate 212 into the second storage tank 203.

[0104] After entering the second storage tank 203, the liquid level gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 5:5, the static pressure sensor P2 sends a signal to the drain switch valve F2. The drain switch valve F2 opens and closes after a delay. The refrigerant at the bottom of the second storage tank 203 flows to the main outlet pipe through the drain switch valve F2 and the drain check valve Z2. When the static pressure sensor P2 detects that the static pressure is less than the corresponding static pressure preset value, the drain switch valve F2 stops opening, and the liquid level continues to rise. When the liquid level is higher than the upper edge of the second storage tank 203, the lubricating oil or the mixture of lubricating oil and refrigerant overflows from the arc-shaped partition plate 212 into the third storage tank 204.

[0105] After entering the third storage tank 204, the liquid level gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 3:7, the static pressure sensor P3 sends a signal to the drain switch valve F3. The drain switch valve F3 opens and closes after a delay. The refrigerant at the bottom of the third storage tank 204 flows to the main outlet pipe through the drain switch valve F3 and the drain check valve Z3. When the static pressure sensor P3 detects that the static pressure is less than the corresponding static pressure preset value, the drain switch valve F3 stops opening, and the liquid level continues to rise. When the liquid level is higher than the upper edge of the third storage tank 204, the lubricating oil or the mixture of lubricating oil and refrigerant overflows from the arc-shaped partition plate 212 to the fourth storage tank 205.

[0106] After entering the fourth storage tank 205, the liquid level gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 1.5:8.5, the static pressure sensor P4 sends a signal to the switching valve F4. The drain switching valve F4 opens and closes after a delay. The refrigerant at the bottom of the fourth storage tank 205 flows to the main outlet pipe through the drain switching valve F4 and the drain check valve Z4. When the static pressure sensor P3 detects that the static pressure is less than the corresponding static pressure preset value, the drain switching valve F4 stops opening, and the liquid level continues to rise. When the liquid level is higher than the upper edge of the fourth storage tank 205, the lubricating oil or the mixture of lubricating oil and refrigerant overflows into the bottom oil storage chamber 208.

[0107] After entering the oil storage chamber 208, the liquid in the oil storage chamber 208 can be discharged by opening the oil drain valves F5 and F6 when the separation switch valve F7 is closed, according to the oil return operation requirements. Alternatively, depending on the separation of refrigerant and lubricating oil, the liquid in the oil storage chamber 208 can be sent back to the first storage tank 202 for further separation when the oil return switch valve F6 is closed.

[0108] Drain check valves Z1, Z2, Z3, and Z4 are used to prevent refrigerant backflow during drain operations. Separation check valve Z5 prevents gas in the upper part of housing 201 from entering the drain pipe through the return pipe when drain valve F5 and separation valve F7 are opened.

[0109] Figure 4This is a schematic diagram of another horizontal oil separator provided in an embodiment of this application. Figure 4 As shown, the horizontal oil separator provided in this embodiment... Figure 2 The illustrated embodiment has been improved for application in low-voltage systems.

[0110] The horizontal oil separator provided in this embodiment, compared to Figure 2 The difference between the embodiments shown is:

[0111] The housing also includes an exhaust pipe 213 located directly above the top cover. The exhaust pipe 213 is configured to discharge gas generated inside the housing 201 in a low-pressure environment to the compressor 101.

[0112] In addition, since there may be insufficient pressure when draining oil in the low-pressure system, in order to drain the lubricating oil in the oil storage chamber 208, this embodiment of the application provides a concave sealing cover 215 on the upper part of the oil storage chamber 208, thereby separating the oil storage chamber 208 from other chambers of the housing 201. The concave sealing cover 215 is fixed on one side of the left side wall of the housing 201 and on the other side of the arc-shaped partition plate 212 of the fourth storage tank 205. The bottom of the concave sealing cover 215 is connected to the oil storage chamber 208, and an oil drain check valve Z6 is provided at the connection. An air inlet pipe 216 is provided on the upper part of the oil storage chamber 208 for draining the lubricating oil from the oil storage chamber 208.

[0113] The following is about Figure 4 The separation process of the horizontal oil separator shown in the embodiment will be described as follows:

[0114] The mixed liquid enters from the liquid inlet pipe 209 above the first storage tank 202, and then bends towards the cover side of the housing 201. Through collision, change of flow direction and reduction of flow velocity, the refrigerant liquid and lubricating oil droplets are separated from the refrigerant gas. The refrigerant gas is sucked away by the compressor from one end of the outlet pipe 213. During the process of the refrigerant gas entering the outlet pipe 213, baffles, mist eliminators and other components that increase gas-liquid separation efficiency can be added to the flow path as needed. Refrigerant liquid and lubricating oil drip into the first storage tank 202, and the liquid level in the first storage tank 202 gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 7:3, the static pressure sensor P1 sends a signal to the drain switch valve F1. The drain switch valve F1 opens and closes after a delay. The refrigerant at the bottom of the first storage tank 202 flows to the liquid outlet manifold through the drain switch valve F1 and the drain check valve Z1. When the static pressure sensor P1 detects that the static pressure is less than the corresponding static pressure preset value, the drain switch valve F1 stops opening, and the liquid level continues to rise. When the liquid level is higher than the upper edge of the first storage tank 202, the lubricating oil or the mixture of lubricating oil and refrigerant overflows into the second storage tank 203.

[0115] After entering the second storage tank 203, the liquid level gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 5:5, the static pressure sensor P2 sends a signal to the drain valve F2. The drain valve F2 opens and closes after a delay. The refrigerant at the bottom of the second storage tank 203 flows to the main outlet pipe through the drain valve F2 and the drain check valve Z2. When the static pressure sensor P2 detects that the static pressure is less than the corresponding preset static pressure value, the drain valve F2 stops opening, and the liquid level continues to rise. When the liquid level exceeds the upper edge of the second storage tank 203, the lubricating oil or the mixture of lubricating oil and refrigerant overflows into the storage tank V3.

[0116] After entering the third storage tank 204, the liquid level gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 3:7, the static pressure sensor P3 sends a signal to the drain switch valve F3. The drain switch valve F3 opens and closes after a delay. The refrigerant at the bottom of the third storage tank 204 flows to the main outlet pipe through the drain switch valve F3 and the drain check valve Z3. When the static pressure sensor P3 detects that the static pressure is less than the corresponding static pressure preset value, the drain switch valve F3 stops opening, and the liquid level continues to rise. When the liquid level is higher than the upper edge of the third storage tank 204, the lubricating oil or the mixture of lubricating oil and refrigerant overflows into the fourth storage tank 205.

[0117] After entering the fourth storage tank 205, the liquid level gradually rises. When the volume ratio of refrigerant to lubricating oil reaches 1.5:8.5, the static pressure sensor P4 sends a signal to the switching valve F4. The drain switching valve F4 opens and closes after a delay. The refrigerant at the bottom of the fourth storage tank 205 flows to the main outlet pipe through the drain switching valve F4 and the drain check valve Z4. When the static pressure sensor P3 detects that the static pressure is less than the corresponding static pressure preset value, the drain switching valve F4 stops opening, and the liquid level continues to rise. When the liquid level is higher than the upper edge of the fourth storage tank 205, the lubricating oil or the mixture of lubricating oil and refrigerant overflows to the lower concave sealing cover and is collected. It then falls into the bottom oil storage chamber 208 through the oil drain check valve Z6 at the bottom of the concave sealing cover.

[0118] After entering the oil storage chamber 208, the liquid can be discharged from the oil storage chamber 208 by opening the oil drain valves F5 and F6 when the separation switch valve F7 is closed, according to the oil return operation requirements. Alternatively, depending on the separation of refrigerant and lubricating oil, the liquid can be returned to the first storage tank 202 for further separation by opening the oil drain valve F5 and the separation switch valve F7 when the oil return switch valve F6 is closed. When the refrigerant temperature is low, the lubricating oil viscosity is high, making oil discharge very difficult. In this case, high-pressure gas can be sent into the oil storage chamber 208 from the inlet pipe 216 to force the lubricating oil out of the oil storage chamber 208.

[0119] In this embodiment, if the lubricating oil viscosity is high, re-separation is not required, meaning that the separation check valve Z5 does not need to be installed on the return pipeline.

[0120] Liquid drain check valves Z1, Z2, Z3, and Z4 are used to prevent refrigerant backflow during liquid draining operations. Oil drain check valve Z6 is used to prevent high-pressure gas from forcing the lubricating oil in the oil reservoir 208 back into the upper chamber of the concave sealing cover during oil draining.

[0121] This application embodiment also provides a lubricating oil separation method, applied to the control module of the horizontal oil separation device in the above embodiments, the method comprising:

[0122] The mixed liquid to be separated is sent into the storage tank at the highest side of the storage tank; when the static pressure detected by the static pressure sensor in each storage tank is greater than the preset static pressure value, the drain valve of the corresponding storage tank is opened and then closed after a delay; when the separation state of the oil storage chamber meets the preset oil return requirements, the drain valve and the oil return valve are opened and the separation valve is closed; otherwise, the drain valve and the separation valve are opened and the drain valve is closed.

[0123] This application also provides a refrigeration system for use in a high-pressure system, wherein a horizontal oil separator is introduced into the inlet pipe with a mixed liquid containing refrigerant and lubricating oil.

[0124] This application also provides a refrigeration system for use in a low-pressure system. In this refrigeration system, the inlet pipe of the horizontal oil separator is used to input a mixed liquid containing refrigerant and lubricating oil, the inlet pipe is used to input high-pressure gas, and the outlet pipe is connected to the compressor.

[0125] Both of the above-mentioned refrigeration systems can effectively separate the mixed liquid containing refrigerant and lubricating oil that enters from the liquid inlet pipe, which not only allows the lubricating oil and refrigerant to be recycled, but also ensures the heat transfer efficiency of the refrigeration system.

[0126] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A horizontal oil separator, characterized in that, include: The housing includes a horizontal cylindrical body with chambers and caps located at both ends of the horizontal cylindrical body; Several storage tanks are arranged horizontally on the bottom of the horizontal cylinder in order of height. Each storage tank has a drain pipe at the bottom that flows to the main outlet pipe, and each drain pipe is provided with a drain switch valve and a drain check valve in the direction of outflow. A plurality of static pressure sensors are provided, each corresponding to one of the plurality of storage tanks, and each static pressure sensor is installed at the same horizontal height on the corresponding drain pipe. The static pressure sensors are associated with the drain switch valve of the corresponding storage tank. The inlet pipe is used to deliver the mixed liquid to be separated into the storage tank at the highest side of the storage tank. An oil storage chamber is formed at the bottom of the chamber on the side with the lowest height of the storage tank. The bottom of the shell is provided with an oil drain pipe that connects to the oil storage chamber. An oil drain switch valve is provided in the outflow direction of the oil drain pipe. One outlet of the oil drain switch valve is connected to a return oil switch valve, and the other outlet is provided with a separation switch valve and a separation check valve in sequence and connected to the uppermost storage tank. The control module is electrically connected to each static pressure sensor, drain valve, oil drain valve, return valve, and disconnect valve. The control module is used for: The mixed liquids to be separated are fed into the storage tank at the highest point of the storage tank. When the static pressure detected by the static pressure sensor in each storage tank is greater than the preset static pressure value, the corresponding storage tank's drain valve is opened and then closed after a delay. When the separation state of the oil storage chamber meets the preset oil return requirements, the control valves for the oil drain and return are opened, and the separation valve is closed; otherwise, the control valves for the oil drain and separation are opened, and the oil drain valve is closed.

2. The horizontal oil separator according to claim 1, characterized in that, The static pressure preset values ​​of the plurality of static pressure sensors decrease sequentially as the height of the storage tank decreases.

3. The horizontal oil separator according to claim 2, characterized in that, The storage tank is provided with four tanks; Accordingly, the static pressure preset values ​​of the four static pressure sensors, from high to low, are as follows: The static pressure sensor is installed at the top edge of the storage tank, where 30% of the lubricating oil and 70% of the refrigerant are stored to generate static pressure. The static pressure sensor is installed at the top edge of the storage tank, where 50% of the lubricating oil and 50% of the refrigerant are stored to generate static pressure. The static pressure sensor is installed at the top edge of the storage tank, where 70% of the lubricating oil and 30% of the refrigerant are stored to generate static pressure. The static pressure sensor is installed at the horizontal line to the upper edge of the storage tank, storing the static pressure generated by 85% lubricating oil and 15% refrigerant.

4. The horizontal oil separator according to claim 1, characterized in that, Also includes: An exhaust pipe is located above the housing.

5. The horizontal oil separator according to claim 4, characterized in that, The upper part of the oil storage chamber is separated by a concave sealing cover. The bottom of the concave sealing cover is connected to the oil storage chamber, and an oil drain check valve is provided at the connection. An air inlet pipe is provided at the upper part of the oil storage chamber.

6. The horizontal oil separator according to any one of claims 1-5, characterized in that, The storage tanks are vertically separated by bow-shaped partitions.

7. The horizontal oil separator according to claim 6, characterized in that, The upper edge of the bow-shaped partition plate is provided with a serrated notch.

8. The horizontal oil separator according to claim 6, characterized in that, An ultrasonic generator is installed on one side of the deepest arc-shaped partition plate of the storage tank, which can generate a horizontal planar sound beam.

9. A method for separating lubricating oil, characterized in that, The method, applied to the control module of the horizontal oil separator according to any one of claims 1-8, comprises: The mixed liquids to be separated are fed into the storage tank at the highest point of the storage tank. When the static pressure detected by the static pressure sensor in each storage tank is greater than the preset static pressure value, the corresponding storage tank's drain valve is opened and then closed after a delay. When the separation state of the oil storage chamber meets the preset oil return requirements, the control valves for the oil drain and return are opened, and the separation valve is closed; otherwise, the control valves for the oil drain and separation are opened, and the oil drain valve is closed.

10. A refrigeration system, characterized in that, Includes the horizontal oil separator as described in any one of claims 1-9.

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