Refrigeration system refrigerant filtering and cleaning device and method

Abstract

A refrigerant filtering and cleaning device and method for a refrigeration system, the device comprises a long cylindrical body, with a cylindrical inner cavity and an inlet end and an outlet end; a filtering and cleaning assembly is arranged in the cylindrical inner cavity, which is composed of a first guide plate, a first filter screen, a filter element and a second filter screen; the filter element is provided with a guide channel above and a separation chamber below; the filter element is filled with molecular sieves and activated carbon for filtering out moisture and impurities; the first guide plate is connected to the front end of the filter element to guide the refrigerant to be filtered to flow upward and enter the guide channel; the first filter screen is arranged at the bottom of the guide channel for passing non-condensable gas; the second filter screen is arranged at the rear end of the separation chamber for filtering lubricating oil; and it also includes an exhaust pipe and an oil return pipe. The present invention provides an integrated filtering solution for refrigerants, which simplifies the complex, reduces processing costs and installation and maintenance costs, and at the same time, due to the reduction of installation leakage points, it also ensures the reliability of the system's long-term operation.

Description

Technical Field

[0001] The present invention relates to the field of refrigeration technology, and in particular to a refrigerant filtering and cleaning device and method for a refrigeration system. Background Art

[0002] Refrigeration systems are used to cool a local environment and currently typically have a compressor for compressing a refrigerant.

[0003] The problem with existing refrigeration systems is that for refrigeration systems that use screw compressors, the refrigerant in the system is mixed with lubricating oil, as well as a small amount of non-condensable gas, moisture and impurities. Refrigerant and lubricating oil are essential to the refrigeration cycle, while non-condensable gas, moisture and impurities are unnecessary but inevitable. At this time, the refrigerant needs to be filtered and cleaned. However, the existing technology usually uses different devices dispersed in different positions of the system to process different objects separately when performing non-condensable gas separation, dry filtration and compressor external refrigeration system lubricating oil separation. The structure is complex and the volume is large, resulting in high overall production, installation and maintenance costs. In addition, due to the high complexity of the system, the possibility of leakage is also increased, affecting the reliability of the system's long-term operation.

[0004] Therefore, how to solve the above-mentioned deficiencies in the prior art has become a subject to be studied and solved by the present invention. Summary of the invention

[0005] The object of the present invention is to provide a refrigerant filtering and cleaning device and method for a refrigeration system.

[0006] In order to achieve the above object, the technical solution adopted by the present invention is:

[0007] A refrigerant filtering and cleaning device for a refrigeration system, used for filtering and cleaning the liquid refrigerant to be filtered flowing out of a condenser of the refrigeration system, and sending the filtered refrigerant into a throttling device of the refrigeration system;

[0008] The refrigerant filtering and cleaning device comprises a horizontally arranged long cylindrical body, the long cylindrical body having a cylindrical inner cavity and an inlet end and an outlet end respectively connected to the front and rear ends of the cylindrical inner cavity, the inlet end being used to connect to the condenser, and the outlet end being used to connect to the throttling device;

[0009] A filter cleaning assembly is provided in the cylindrical inner cavity, and the filter cleaning assembly is composed of a first guide plate, a first filter screen, a filter element and a second filter screen;

[0010] The filter element has a horizontal length, the front end of which is arranged corresponding to the inlet end of the cylindrical inner cavity, and the rear end is arranged corresponding to the outlet end of the cylindrical inner cavity; the top of the filter element is the inflow side of the refrigerant to be filtered, and is spaced apart from the top of the cylindrical inner cavity to form a guide channel; the bottom of the filter element is the outflow side of the refrigerant, and is spaced apart from the bottom of the cylindrical inner cavity to form a separation chamber; the interior of the filter element is filled with molecular sieves and activated carbon, which are used to filter out moisture and impurities in the refrigerant to be filtered, and the filtered refrigerant and lubricating oil enter the separation chamber;

[0011] The first guide plate is connected to the front end of the filter element and is vertically arranged to close the front end of the separation chamber; the upper end height of the first guide plate corresponds to the upper surface height of the filter element, so as to guide the refrigerant to be filtered entering the cylindrical inner cavity to flow upward, so that the refrigerant to be filtered enters the guide channel;

[0012] The first filter screen is vertically fixed on the upper side of the rear end of the filter element and is blocked at the bottom of the guide channel; the first filter screen includes a polytetrafluoroethylene liquid-proof breathable membrane, which is used to pass the non-condensable gas in the refrigerant to be filtered so that the non-condensable gas enters the rear section of the cylindrical inner cavity; other substances in the refrigerant to be filtered are blocked by the polytetrafluoroethylene liquid-proof breathable membrane and enter the filter element instead;

[0013] The second filter screen is vertically fixed on the lower side of the rear end of the filter element and is blocked at the rear end of the separation chamber; the second filter screen includes a stainless steel mesh body, and the mesh number of the stainless steel mesh body is 20-40 meshes, which is used to filter the lubricating oil in the separation chamber and block the lubricating oil in the separation chamber; the refrigerant in the separation chamber passes through the second filter screen and enters the rear section of the cylindrical inner cavity;

[0014] It also includes an exhaust pipeline and an oil return pipeline; the exhaust pipeline is connected to the top of the cylindrical inner cavity, and the connection is located at the rear side of the first filter screen, and is used to discharge the non-condensable gas passing through the first filter screen; the exhaust pipeline is connected in series with a first valve for opening and closing the exhaust pipeline;

[0015] The oil return pipeline is connected to the bottom of the separation chamber and is used to discharge the lubricating oil that is blocked by the second filter and accumulated in the separation chamber; a second valve for opening and closing the oil return pipeline is connected in series to the oil return pipeline.

[0016] In the above scheme, the refrigerant to be filtered is in liquid state, which is mixed with lubricating oil, a small amount of non-condensable gas, water and impurities.

[0017] In the above solution, the oil return pipeline can be directly connected to the lubricating oil supply unit of the refrigeration system to achieve filtering and recycling of the lubricating oil.

[0018] In the above scheme, the first filter screen uses a polytetrafluoroethylene liquid-proof breathable membrane. Since the distance between gas molecules is large, they can pass through the breathable holes on the breathable membrane during diffusion movement, while the distance between liquid molecules is smaller than the distance between the breathable holes, and under the action of surface tension, the liquid molecules cannot pass through. The prior art does not separate the gas, but directly discharges the refrigerant containing gas. The present invention separates the non-condensable gas by setting the first filter screen, which can achieve the discharge of only the gas, avoiding unnecessary consumption of the refrigerant.

[0019] In a further technical solution, the diameters of the inlet end and the outlet end are both smaller than the diameter of the cylindrical inner cavity. With this design, the long cylindrical body of the refrigerant filtering and cleaning device of this case can become an expanded pipeline, thereby realizing the liquid storage function, thereby replacing the liquid storage device in the traditional refrigeration system, and further simplifying the refrigeration system by omitting the liquid storage device.

[0020] According to a further technical solution, the inlet end of the long cylindrical body is detachably sealed and assembled with the outflow pipe of the condenser, and the outlet end is detachably sealed and assembled with the inflow pipe of the throttling device. Specifically, the detachable sealing assembly can be achieved through a pipe flange with a sealing ring, thereby ensuring the sealing performance and facilitating the disassembly and maintenance of the refrigerant filtering and cleaning device in the future.

[0021] According to a further technical solution, the filter element comprises activated carbon layers and zeolite molecular sieve layers alternately stacked from top to bottom, and the activated carbon and zeolite molecular sieve are used to adsorb and filter the moisture and impurities in the refrigerant to be filtered separately or simultaneously.

[0022] According to a further technical solution, the first filter screen further comprises a support screen, which is arranged at the rear side of the polytetrafluoroethylene liquid-proof breathable membrane and is used to support and reinforce the polytetrafluoroethylene liquid-proof breathable membrane. This solves the problem of the polytetrafluoroethylene liquid-proof breathable membrane being broken due to the impact pressure of the liquid during long-term filtering work, and strengthens the strength of the membrane.

[0023] In a further technical solution, the second filter screen also includes a conical filter screen body, the mouth of which is fixedly arranged on the rear side of the stainless steel screen body, and the outline of the mouth is consistent with the outline of the stainless steel screen body; the mesh number of the conical filter screen body is 20-40 meshes, which is larger than the mesh number of the stainless steel screen body. Since the lubricating oil has its own viscosity, it will adhere to the stainless steel screen body when passing through the stainless steel screen body, thereby playing a filtering effect on the lubricating oil, and the composite structure design of the stainless steel screen body and the conical filter screen body can further improve the filtering effect on the lubricating oil, so that the refrigerant entering the throttling device has a higher purity.

[0024] A further technical solution also includes a second guide plate fixedly mounted on the top of the cylindrical inner cavity; the second guide plate is tilted, with its upper end located on the rear side of the exhaust pipe and its lower end tilted toward the filter element, so that its tilted front side surface becomes a guide surface for non-condensable gas, thereby directing the filtered gas to the location where the exhaust pipe is set.

[0025] In a further solution, a closed exhaust chamber may be provided at the rear side of the first filter screen, and the exhaust chamber is connected to the top of the cylindrical inner cavity; the exhaust pipeline is connected to the exhaust chamber. After the system has been working for a period of time, the gas entering the exhaust chamber gradually accumulates, thereby triggering the first valve to open for exhaust.

[0026] A further technical solution further includes a first pressure sensor and a second pressure sensor;

[0027] The first pressure sensor is fixed on the inner wall of the cylindrical inner cavity and is arranged corresponding to the rear side of the first filter; the first pressure sensor is electrically connected to a control circuit, and the control circuit is electrically connected to the first valve; the pressure on the air outlet side of the first filter is detected in real time by the first pressure sensor to determine whether there is a gas accumulation problem, thereby triggering the first valve to open for exhaust.

[0028] The second pressure sensor is fixed at the bottom of the separation chamber; the second pressure sensor is electrically connected to a control circuit, and the control circuit is electrically connected to the second valve. The second pressure sensor detects the liquid pressure at the bottom of the separation chamber in real time to determine whether there is a lubricating oil accumulation problem, thereby triggering the second valve to open for oil discharge.

[0029] The first pressure sensor and the second pressure sensor may be conventional pressure sensors or high-precision resistive induction sensors.

[0030] A further technical solution includes a first backflush nozzle and a second backflush nozzle;

[0031] The first back-blowing nozzle is arranged directly opposite to the rear side of the first filter; the first back-blowing nozzle is electrically connected to a control circuit and is used to periodically back-blow the first filter; after the system has worked for a certain period, in order to ensure that the refrigeration system operates online for a long time without stopping, the first back-blowing nozzle can be used to intermittently back-blown the first filter, and the attachments on the first filter can be removed through a short gas impact force, thereby ensuring that the first filter can pass gas normally.

[0032] It also includes a second back-blowing nozzle, which is arranged opposite to the rear side of the second filter; the second back-blowing nozzle is electrically connected to the control circuit and is used to periodically back-blow the second filter. After the system has worked for a certain period of time, in order to ensure that the refrigeration system can operate online for a long time without stopping, the second back-blowing nozzle can be used to back-blow the second filter to blow the lubricating oil attached to the second filter back into the separation chamber to ensure that the second filter can pass the refrigerant normally.

[0033] The first back-blowing nozzle and the second back-blowing nozzle are respectively connected to the exhaust side of the screw compressor through pipelines. During back-blowing, high-pressure gaseous refrigerant is sprayed to achieve the back-blowing effect. The frequency of back-blowing and the time of a single back-blowing can be set according to demand. The total back-blowing time can be set in direct proportion to the continuous working time of the system, that is, the longer the system continues to work, the total back-blowing time can be appropriately extended.

[0034] The present invention also discloses a method for filtering and cleaning refrigerant in a refrigeration system, comprising:

[0035] Step 1: Send the refrigerant to be filtered into the cylindrical inner cavity from the inlet end of the refrigerant filtering and cleaning device, and guide the ascending flow by the first guide plate to enter the guide channel above the filter element;

[0036] Step 2: The non-condensable gas in the refrigerant to be filtered passes through the first filter screen and enters the rear section of the cylindrical inner cavity and is discharged through the exhaust pipe, while other substances are blocked by the first filter screen and enter the filter element for filtration;

[0037] Step 3: The water and impurities in the refrigerant to be filtered are removed by filtering and cleaning the filter element, and the mixture of refrigerant and lubricating oil enters the separation chamber;

[0038] Step 4: the refrigerant in the mixture in the separation chamber passes through the second filter screen and enters the rear section of the cylindrical inner cavity, the lubricating oil in the mixture is blocked by the second filter screen, and is discharged through the oil return pipeline after being accumulated in the separation chamber;

[0039] Step 5: The refrigerant passing through the second filter screen flows to the throttling device via the outlet end of the refrigerant filtering and cleaning device.

[0040] The terms “first”, “second”, etc. used in this document do not specifically refer to an order or sequence, nor are they used to limit the present case. They are only used to distinguish components or operations described with the same technical terms.

[0041] As used herein, “connected” or “positioned” may refer to two or more components or devices being in direct physical contact with each other, or being in indirect physical contact with each other, or may refer to two or more components or devices operating or moving with each other.

[0042] The terms “include,” “including,” “have,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0043] The terms used in this document generally have the ordinary meaning of each term used in this field, in the context of the case and in the specific context, unless otherwise noted. Certain terms used to describe the present invention will be discussed below or elsewhere in this specification to provide additional guidance to those skilled in the art in describing the present invention.

[0044] The terms "front", "back", "up", "down", "left", "right", etc. used in this article are all directional terms. In this case, they are only used to illustrate the positional relationship between the various structures, and are not used to limit the protection plan of this case and the specific direction during actual implementation.

[0045] The working principle and advantages of the present invention are as follows:

[0046] 1. The present invention provides an integrated filtering solution for refrigerants, which can complete the removal of non-condensable gases in the refrigerant, the filtering and absorption of moisture and impurities, and the separation and discharge of lubricating oil at one time through the same device. Compared with the prior art, the overall structure of the device is greatly simplified, which is not only conducive to reducing processing costs, but also conducive to reducing installation and maintenance costs, and has a good industry application prospect; at the same time, since the leakage points of the installation are reduced, the reliability of the long-term operation of the system is also guaranteed.

[0047] 2. The filtering and cleaning component of the present invention is composed of a first guide plate, a first filter screen, a filter element and a second filter screen, which are arranged compactly and have a reasonable spatial layout. Not only can the respective filtering and separation functions be realized, but also the different forms of gas and liquid, as well as the different material properties of refrigerants and lubricating oils are cleverly utilized. The guide channel and the diversion chamber formed by the layout cooperate with the first filter screen, the filter element and the second filter screen to realize targeted processing, so that the filtering and cleaning component of the device is not only compact in structure and reasonable in layout, but also has efficient and reliable processing effect, which is conducive to improving the efficiency and stability of the system movement.

[0048] 3. The present invention can achieve good gas-liquid separation and ensure its own structural strength through the innovatively designed first filter structure. The separated non-condensable gas is discharged in a targeted manner through the exhaust pipeline, which can reduce the refrigerant waste problem caused by directly discharging the refrigerant mixed with gas in the traditional process, making the gas discharge more efficient.

[0049] 4. The present invention designs the filter element to be composed of activated carbon layers and zeolite molecular sieve layers alternately stacked from top to bottom, and uses the activated carbon and zeolite molecular sieves to adsorb and filter the moisture and impurities in the refrigerant to be filtered multiple times separately or simultaneously, thereby achieving the effect of fully removing moisture and impurities.

[0050] 5. The present invention can effectively block the lubricating oil in the refrigerant through the innovatively designed second filter structure, and can also achieve double-layer filtration through the composite conical filter body, thereby ensuring the separation effect of the lubricating oil and the refrigerant. The separated lubricating oil can be collected through the separation chamber and can be returned to the lubricating oil supply unit through the return oil pipeline, thereby achieving the filtration and recycling of the lubricating oil.

[0051] 6. The present invention further provides two back-blowing nozzles, which are used to regularly spray high-pressure gaseous refrigerant onto the first filter and the second filter, thereby removing the attachments on the first filter and the lubricating oil attached to the second filter, thereby extending the online working time of the filter cleaning device of the present invention, thereby ensuring that the system can operate for a long time without stopping.

[0052] 7. The present invention further provides pressure sensors for the exhaust pipeline and the oil return pipeline, so as to realize the automation of exhaust and oil return.

[0053] 8. The long cylindrical body of the present invention can be configured as an expansion pipeline to achieve a liquid storage function, thereby replacing a liquid storage device in a traditional refrigeration system, and further simplifying the refrigeration system by eliminating the liquid storage device. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Attached Figure 1 This is a schematic structural diagram of a refrigerant filtering and cleaning device according to an embodiment of the present invention;

[0055] Attached Figure 2 for Figure 1 AA section view;

[0056] Attached Figure 3 The figure is a flow chart of a refrigerant filtering and cleaning method according to an embodiment of the present invention.

[0057] In the above drawings: 1. long cylindrical body; 2. cylindrical inner cavity; 3. inlet end; 4. outlet end; 5. first guide plate; 6. first filter screen; 61. polytetrafluoroethylene liquid-proof breathable membrane; 62. support net; 7. filter element; 8. second filter screen; 81. stainless steel mesh body; 82. conical filter mesh body; 9. flow guide channel; 10. separation chamber; 11. molecular sieve; 12. activated carbon; 13. exhaust pipeline; 14. oil return pipeline; 15. first valve; 16. second valve; 17. second guide plate; 18. first pressure sensor; 19. second pressure sensor; 20. first backflush nozzle; 21. second backflush nozzle. DETAILED DESCRIPTION

[0058] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0059] Embodiment: The present invention will be clearly described below with diagrams and detailed descriptions. After understanding the embodiments of the present invention, any person skilled in the art can make changes and modifications based on the techniques taught by the present invention without departing from the spirit and scope of the present invention.

[0060] The terms used herein are only for describing specific embodiments and are not intended to be limiting of the present invention. Singular forms such as "a", "this", "here", "this" and "the" as used herein also include plural forms.

[0061] See attached Figure 1 As shown, a refrigerant filtering and cleaning device for a refrigeration system is used to filter and clean the liquid refrigerant to be filtered flowing out of a condenser of the refrigeration system, and send the filtered refrigerant into a throttling device of the refrigeration system.

[0062] The refrigerant filtering and cleaning device includes a horizontally arranged long cylindrical body 1, which has a cylindrical inner cavity 2 and an inlet end 3 and an outlet end 4 respectively connected to the front and rear ends of the cylindrical inner cavity 2, the inlet end 3 is used to connect to the condenser, and the outlet end 4 is used to connect to the throttling device.

[0063] A filtering and cleaning assembly is disposed in the cylindrical inner cavity 2 , and the filtering and cleaning assembly is composed of a first guide plate 5 , a first filter screen 6 , a filter element 7 and a second filter screen 8 .

[0064] Among them, the filter element 7 has a horizontal length, and its front end is set corresponding to the inlet end 3 of the cylindrical inner cavity 2, and the rear end is set corresponding to the outlet end 4 of the cylindrical inner cavity 2; the top of the filter element 7 is the inflow side of the refrigerant to be filtered, and is spaced apart from the top of the cylindrical inner cavity 2 to form a guide channel 9; the bottom of the filter element 7 is the outflow side of the refrigerant, and is spaced apart from the bottom of the cylindrical inner cavity 2 to form a separation chamber 10; the interior of the filter element 7 is filled with molecular sieves 11 and activated carbon 12, which are used to filter out moisture and impurities in the refrigerant to be filtered, and the filtered refrigerant and lubricating oil enter the separation chamber 10.

[0065] The first guide plate 5 is connected to the front end of the filter element 7 and is vertically arranged to close the front end of the separation chamber 10; the upper end height of the first guide plate 5 corresponds to the upper surface height of the filter element 7, so as to guide the upward flow of the refrigerant to be filtered entering the cylindrical inner cavity 2, so that the refrigerant to be filtered enters the guide channel 9; the length of the guide channel 9 corresponds to the length of the filter element 7.

[0066] The first filter screen 6 is vertically fixed on the upper side of the rear end of the filter element 7 and is blocked at the bottom of the guide channel 9; the first filter screen 6 includes a polytetrafluoroethylene liquid-proof breathable membrane 61, which is used to pass the non-condensable gas in the refrigerant to be filtered and allow the non-condensable gas to enter the rear section of the cylindrical inner cavity 2; other substances in the refrigerant to be filtered are blocked by the polytetrafluoroethylene liquid-proof breathable membrane 61 and enter the filter element 7 instead.

[0067] The first filter screen 6 uses a polytetrafluoroethylene liquid-proof breathable membrane 61. Since the distance between gas molecules is large, they can pass through the air holes on the breathable membrane during diffusion movement, while the distance between liquid molecules is smaller than the distance between the air holes, and under the action of surface tension, liquid molecules cannot pass through.

[0068] The prior art does not separate the gas, but directly discharges the refrigerant containing the gas. The present invention separates the non-condensable gas by setting a first filter 6, so that only the gas can be discharged, thus avoiding unnecessary consumption of the refrigerant.

[0069] Preferably, the first filter screen 6 further includes a support screen 62, which is arranged at the rear side of the polytetrafluoroethylene liquid-proof breathable membrane 61 and can be made of a material with a certain structural strength such as stainless steel, and is used to support and reinforce the polytetrafluoroethylene liquid-proof breathable membrane 61. This solves the problem of the polytetrafluoroethylene liquid-proof breathable membrane 61 being broken due to the impact pressure of the liquid during long-term filtration, and strengthens the strength of the membrane.

[0070] The second filter screen 8 is vertically fixed on the lower side of the rear end of the filter element 7 and is blocked at the rear end of the separation chamber 10; the second filter screen 8 includes a stainless steel mesh body 81, and the mesh number of the stainless steel mesh body 81 is 20~40 meshes, which is used to filter the lubricating oil in the separation chamber 10 and block the lubricating oil in the separation chamber 10; the refrigerant in the separation chamber 10 passes through the second filter screen 8 and enters the rear section of the cylindrical inner cavity 2.

[0071] Preferably, the second filter screen 8 also includes a conical filter screen body 82, the mouth of the conical filter screen body 82 is fixedly arranged on the rear side of the stainless steel screen body 81, and the outline of the mouth is consistent with the outline of the stainless steel screen body 81; the mesh number of the conical filter screen body 82 is 20~40 meshes, which is larger than the mesh number of the stainless steel screen body 81.

[0072] Since the lubricating oil has its own viscosity, it will adhere to the stainless steel mesh 81 when passing through the stainless steel mesh 81, thereby filtering the lubricating oil. The composite structure design of the stainless steel mesh 81 and the conical filter mesh 82 can further enhance the filtering effect of the lubricating oil, thereby making the refrigerant entering the throttling device more pure.

[0073] It also includes an exhaust pipeline 13 and an oil return pipeline 14; the exhaust pipeline 13 is connected to the top of the cylindrical inner cavity 2, and the connection is located at the rear side of the first filter 6, which is used to discharge the non-condensable gas passing through the first filter 6; the exhaust pipeline 13 is connected in series with a first valve 15 for opening and closing the exhaust pipeline 13.

[0074] The oil return line 14 is connected to the bottom of the separation chamber 10, and is used to discharge the lubricating oil that is blocked by the second filter screen 8 and accumulated in the separation chamber 10; the oil return line 14 is connected in series with a second valve 16 for opening and closing the oil return line 14. The oil return line 14 can be directly connected to the lubricating oil supply unit of the refrigeration system to achieve filtering and recycling of the lubricating oil.

[0075] Preferably, the diameters of the inlet end 3 and the outlet end 4 are both smaller than the diameter of the cylindrical inner cavity 2. With this design, the long cylindrical body 1 of the refrigerant filtering and cleaning device of the present case can become an expanded pipeline, thereby realizing the liquid storage function, thereby replacing the liquid storage device in the traditional refrigeration system, and further simplifying the refrigeration system by omitting the liquid storage device.

[0076] Preferably, the inlet end 3 of the long cylindrical body 1 is detachably sealed and assembled with the outflow pipe of the condenser, and the outlet end 4 is detachably sealed and assembled with the inflow pipe of the throttling device. Specifically, the detachable sealing assembly can be achieved by, for example, a pipe flange with a sealing ring, thereby ensuring the sealing performance and facilitating the disassembly and maintenance of the refrigerant filtering and cleaning device in the future.

[0077] Preferably, the filter element 7 comprises activated carbon layers and zeolite molecular sieve layers alternately stacked from top to bottom, and the activated carbon 12 and the zeolite molecular sieve 11 are used to adsorb and filter the moisture and impurities in the refrigerant to be filtered separately or simultaneously.

[0078] Preferably, it also includes a second guide plate 17, which is fixed on the top of the cylindrical inner cavity 2; the second guide plate 17 is inclined, with its upper end located on the rear side of the exhaust pipe 13, and its lower end inclined toward the filter element 7, so that its inclined front side surface becomes a guide surface for non-condensable gas, and guides the filtered gas to the setting of the exhaust pipe 13.

[0079] In a further solution, a closed exhaust chamber (not shown) may be provided at the rear side of the first filter screen 6, and the exhaust chamber is connected to the top of the cylindrical inner cavity 2; the exhaust pipe 13 is connected to the exhaust chamber. After the system has been working for a period of time, the gas entering the exhaust chamber gradually accumulates, thereby triggering the first valve 15 to open for exhaust.

[0080] Preferably, a first pressure sensor 18 and a second pressure sensor 19 are also included.

[0081] The first pressure sensor 18 is fixedly mounted on the inner wall of the cylindrical inner cavity 2 and is arranged corresponding to the rear side of the first filter screen 6; the first pressure sensor 18 is electrically connected to a control circuit, and the control circuit is electrically connected to the first valve 15. The first pressure sensor 18 detects the pressure on the outlet side of the first filter screen 6 in real time to determine whether there is a gas accumulation problem, thereby triggering the first valve 15 to open for exhaust.

[0082] The second pressure sensor 19 is fixedly mounted at the bottom of the separation chamber 10 ; the second pressure sensor 19 is electrically connected to a control circuit, and the control circuit is electrically connected to the second valve 16 .

[0083] The second pressure sensor 19 is used to detect the liquid pressure at the bottom of the separation chamber 10 in real time to determine whether there is a lubricating oil accumulation problem, thereby triggering the second valve 16 to open for oil drainage.

[0084] The first pressure sensor 18 and the second pressure sensor 19 can both be conventional pressure sensors or high-precision resistive induction sensors.

[0085] Preferably, it also includes a first back-blowing nozzle 20 and a second back-blowing nozzle 21 .

[0086] The first back-blowing nozzle 20 is arranged opposite to the rear side of the first filter 6; the first back-blowing nozzle 20 is electrically connected to the control circuit and is used to periodically back-blow the first filter 6. After the system has worked for a certain period, in order to ensure that the refrigeration system operates online for a long time without stopping, the first back-blowing nozzle 20 can be used to intermittently back-blown the first filter 6, and the attachments on the first filter 6 can be removed by a short gas impact force, so as to ensure that the first filter 6 can pass gas normally.

[0087] It also includes a second back-blowing nozzle 21, which is arranged opposite to the rear side of the second filter 8; the second back-blowing nozzle 21 is electrically connected to the control circuit and is used to periodically back-blow the second filter 8. After the system has worked for a certain period, in order to ensure that the refrigeration system operates online for a long time without stopping, the second back-blowing nozzle 21 can be used to back-blow the second filter 8 to blow the lubricating oil attached to the second filter 8 back into the separation chamber 10, so as to ensure that the second filter 8 can pass the refrigerant normally.

[0088] The first back-blowing nozzle 20 and the second back-blowing nozzle 21 are respectively connected to the exhaust side of the screw compressor through pipelines. During back-blowing, high-pressure gaseous refrigerant is sprayed to achieve the back-blowing effect. The frequency of back-blowing and the time of a single back-blowing can be set according to demand. The total back-blowing time can be set in direct proportion to the continuous working time of the system, that is, the longer the system continues to work, the total back-blowing time can be appropriately extended.

[0089] like Figure 3 As shown, the refrigeration system refrigerant filtering and cleaning method of this embodiment includes:

[0090] Step 1: The refrigerant to be filtered is fed into the cylindrical inner cavity 2 from the inlet end 3 of the refrigerant filtering and cleaning device, and the first guide plate 5 guides the upward flow to enter the guide channel 9 above the filter element 7;

[0091] Step 2: The non-condensable gas in the refrigerant to be filtered passes through the first filter screen 6 and enters the rear section of the cylindrical inner cavity 2 and is discharged through the exhaust pipe 13. Other substances are blocked by the first filter screen 6 and enter the filter element 7 for filtration;

[0092] Step 3: The water and impurities in the refrigerant to be filtered are removed by filtering and cleaning the filter element 7, and the mixture of the refrigerant and the lubricating oil enters the separation chamber 10;

[0093] Step 4: The refrigerant in the mixture in the separation chamber 10 passes through the second filter screen 8 and enters the rear section of the cylindrical inner chamber 2. The lubricating oil in the mixture is blocked by the second filter screen 8 and is discharged through the oil return line 14 after being accumulated in the separation chamber 10.

[0094] Step 5: The refrigerant passing through the second filter screen 8 flows to the throttling device via the outlet port 4 of the refrigerant filtering and cleaning device.

[0095] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A refrigerant filtering and cleaning device for a refrigeration system, characterized in that: The invention comprises a horizontally arranged long cylindrical body (1), wherein the long cylindrical body (1) has a cylindrical inner cavity (2) and an inlet end (3) and an outlet end (4); A filter cleaning assembly is provided in the cylindrical inner cavity (2), the filter cleaning assembly being composed of a first guide plate (5), a first filter screen (6), a filter element (7) and a second filter screen (8); The filter element (7) has a horizontal length, with its front end arranged corresponding to the inlet end (3) and its rear end arranged corresponding to the outlet end (4); the top of the filter element (7) is the inflow side of the refrigerant to be filtered, and is spaced apart from the top of the cylindrical inner cavity (2) to form a guide channel (9); the bottom of the filter element (7) is the outflow side of the refrigerant, and is spaced apart from the bottom of the cylindrical inner cavity (2) to form a separation chamber (10); the interior of the filter element (7) is filled with molecular sieves (11) and activated carbon (12) for filtering out moisture and impurities in the refrigerant to be filtered, and the filtered refrigerant and lubricating oil enter the separation chamber (10); The first guide plate (5) is connected to the front end of the filter element (7) and is arranged vertically, thereby closing the front end of the separation chamber (10); the height of the upper end of the first guide plate (5) corresponds to the height of the upper surface of the filter element (7), so as to guide the refrigerant to be filtered entering the cylindrical inner cavity (2) to flow upward, so that the refrigerant to be filtered enters the guide channel (9); The first filter screen (6) is vertically fixed on the upper side of the rear end of the filter element (7) and is blocked at the bottom of the guide channel (9); the first filter screen (6) comprises a polytetrafluoroethylene liquid-proof breathable membrane (61) for passing non-condensable gas in the refrigerant to be filtered so that the non-condensable gas enters the rear section of the cylindrical inner cavity (2); other substances in the refrigerant to be filtered are blocked by the polytetrafluoroethylene liquid-proof breathable membrane (61) and enter the filter element (7) instead; The second filter screen (8) is vertically fixed on the lower side of the rear end of the filter element (7) and is blocked at the rear end of the separation chamber (10); the second filter screen (8) comprises a stainless steel mesh body (81), and the mesh number of the stainless steel mesh body (81) is 20-40 meshes, and is used to filter the lubricating oil in the separation chamber (10) and block the lubricating oil in the separation chamber (10); the refrigerant in the separation chamber (10) passes through the second filter screen (8) and enters the rear section of the cylindrical inner cavity (2); It also includes an exhaust pipeline (13) and an oil return pipeline (14); the exhaust pipeline (13) is connected to the top of the cylindrical inner cavity, and the connection point is located at the rear side of the first filter screen (6), and is used to discharge non-condensable gas passing through the first filter screen (6); the exhaust pipeline (13) is connected in series with a first valve (15) for opening and closing the exhaust pipeline (13); The oil return pipeline (14) is connected to the bottom of the separation chamber (10) and is used to discharge the lubricating oil that is blocked by the second filter (8) and accumulated in the separation chamber (10); the oil return pipeline (14) is connected in series with a second valve (16) for opening and closing the oil return pipeline (14).

2. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: The diameters of the inlet end (3) and the outlet end (4) are both smaller than the diameter of the cylindrical inner cavity (2).

3. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: The inlet end (3) of the long cylindrical body (1) is detachably sealed and assembled with the outflow pipeline of the condenser, and the outlet end (4) is detachably sealed and assembled with the inflow pipeline of the throttling device.

4. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: The filter element (7) comprises activated carbon layers and zeolite molecular sieve layers alternately stacked from top to bottom, and the activated carbon (12) and the zeolite molecular sieve (11) are used to adsorb and filter the moisture and impurities in the refrigerant to be filtered separately or simultaneously.

5. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: The first filter screen (6) further comprises a support screen (62), the support screen (62) being arranged on the rear side of the polytetrafluoroethylene liquid-proof breathable membrane (61) and being used for supporting and reinforcing the polytetrafluoroethylene liquid-proof breathable membrane (61).

6. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: The second filter screen (8) further comprises a conical filter screen body (82), the mouth of the conical filter screen body (82) being fixedly arranged on the rear side of the stainless steel screen body (81), and the outline of the mouth is consistent with the outline of the stainless steel screen body (81); the mesh number of the conical filter screen body (82) is 20-40 meshes, and the mesh number is greater than the mesh number of the stainless steel screen body (81).

7. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: It also includes a second guide plate (17) fixedly arranged on the top of the cylindrical inner cavity (2); The second guide plate (17) is arranged at an angle, with its upper end being located at the rear side of the exhaust pipe (13) and its lower end being inclined toward the filter element (7), and its inclined front side surface serving as a guide surface for non-condensable gas, thereby directing the filtered gas to the location where the exhaust pipe (13) is arranged.

8. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: Also includes a first pressure sensor (18) and a second pressure sensor (19); The first pressure sensor (18) is fixedly mounted on the inner wall of the cylindrical inner cavity (2) and is arranged corresponding to the rear side of the first filter screen (6); the first pressure sensor (18) is electrically connected to a control circuit, and the control circuit is electrically connected to the first valve (15); The second pressure sensor (19) is fixedly mounted at the bottom of the separation chamber (10); the second pressure sensor (19) is electrically connected to a control circuit, and the control circuit is electrically connected to the second valve (16).

9. The refrigerant filtering and cleaning device for a refrigeration system according to claim 1, characterized in that: It also includes a first back-blowing nozzle (20) and a second back-blowing nozzle (21); The first back-blowing nozzle (20) is arranged directly opposite to the rear side of the first filter screen (6); the first back-blowing nozzle (20) is electrically connected to a control circuit and is used to periodically back-blow the first filter screen (6); It also comprises a second back-blowing nozzle (21) which is arranged opposite to the rear side of the second filter screen (8); the second back-blowing nozzle (21) is electrically connected to the control circuit and is used to periodically back-blow the second filter screen (8).

10. A method for filtering and cleaning refrigerant in a refrigeration system, characterized in that: The refrigerant filtering and cleaning device according to any one of claims 1 to 9 is implemented, and the filtering and cleaning method comprises: Step 1: The refrigerant to be filtered is sent into the cylindrical inner cavity (2) from the inlet end (3) of the refrigerant filtering and cleaning device, and the first guide plate (5) guides the upward flow to enter the guide channel (9) above the filter element (7); Step 2: the non-condensable gas in the refrigerant to be filtered passes through the first filter screen (6) and enters the rear section of the cylindrical inner cavity (2) and is discharged through the exhaust pipe (13); other substances are blocked by the first filter screen (6) and enter the filter element (7) for filtration; Step 3: The water and impurities in the refrigerant to be filtered are removed by filtering and cleaning with the filter element (7), and the mixture of the refrigerant and the lubricating oil enters the separation chamber (10); Step 4: the refrigerant in the mixture in the separation chamber (10) passes through the second filter screen (8) and enters the rear section of the cylindrical inner cavity (2); the lubricating oil in the mixture is blocked by the second filter screen (8) and is discharged through the oil return pipeline (14) after being accumulated in the separation chamber (10); Step 5: The refrigerant that has passed through the second filter screen (8) flows to the throttling device via the outlet end (4) of the refrigerant filtering and cleaning device.

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