Gas filter

Abstract

The utility model discloses a gas filter. The gas filter comprises a shell, the shell comprises an upstream shell and a downstream shell, a gas inlet is formed in one end of the upstream shell, a gas outlet is formed in one end of the downstream shell, and the other end of the upstream shell and the other end of the downstream shell are connected with each other to form a hollow cavity extending in the length direction of the shell; the filter element is arranged in the hollow cavity and forms a plurality of flow channels, the flow channels extend in the length direction of the shell, one end of each flow channel is blocked to form a blind hole, the flow channel opened in the air inlet direction is an upstream flow channel, the flow channel opened in the air outlet direction is a downstream flow channel, a filter membrane is arranged on the wall of the upstream flow channel, and the filter membrane is arranged on the wall of the downstream flow channel. And gas to be filtered is filtered through the filter membrane and the wall on the upstream flow channel. The multi-runner wall flow filter element provided by the utility model is firm and durable, high in filter membrane precision, large in filter area in unit volume, large in operation elasticity and long in online service life due to multi-runner inner surface filtration.

Description

Technical Field

[0001] The utility model relates to the technical field of filters, and particularly relates to a gas filter. Background Art

[0002] In the past few decades, membrane filtration technology has gradually emerged. This technology uses special polymer membrane materials and can achieve efficient separation of fine particles and impurities. However, when dealing with high-flow and high-pressure gases, membrane filtration technology often faces challenges such as membrane breakage and performance degradation. Moreover, in the case of traditional straight-through flow filter structures, the pressure loss is relatively large when dealing with high-flow gases.

[0003] In practical applications, the requirements of different industries for high-purity gas filters are also continuously driving the development of technology. In the semiconductor manufacturing industry, due to the continuous refinement of chip manufacturing processes, the requirements for the size and concentration of impurity particles in gases have reached extremely high standards. The biomedical field has extremely high requirements for gas purity and sterility. Therefore, it not only requires the filter to be able to remove physical impurities but also needs to have the functions of sterilization and antivirus. The aerospace field has special requirements for the lightweight, miniaturization, and extreme environment resistance of filters to reduce the weight of the filter while ensuring the filtration effect and improve its stability in harsh environments such as high temperature, high pressure, and strong radiation.

[0004] In summary, gas filters face many challenges, such as further improving filtration accuracy, extending service life, reducing costs, and adapting to more complex and demanding application environments. Summary of the Utility Model

[0005] An embodiment of the utility model provides a gas filter to solve at least one of the problems existing in the existing gas filters, such as low filtration accuracy, short service life, high cost, and difficulty in adapting to complex and demanding application environments.

[0006] The gas filter provided according to the embodiment of the utility model includes:

[0007] A housing, the housing includes an upstream housing and a downstream housing. An air inlet is provided at one end of the upstream housing, and an air outlet is provided at one end of the downstream housing. The other ends of the upstream housing and the downstream housing are joined to form a hollow chamber extending along the length direction of the housing;

[0008] A filter element, arranged in the hollow chamber. The filter element forms a plurality of flow channels. The flow channels extend along the length direction of the housing. One end of the flow channel is blocked to form a blind hole. The flow channel opening towards the air inlet direction is the upstream flow channel, and the flow channel opening towards the air outlet direction is the downstream flow channel. A filter membrane is provided on the wall of the upstream flow channel, and the gas to be filtered is filtered through the filter membrane and the wall on the upstream flow channel.

[0009] In some embodiments, the filter element is a ceramic filter element, and the filter membrane is a TiO 2 , ZrO 2 or Al 2 O 3 nanoscale membrane.

[0010] In some embodiments, the number of the upstream flow channels is greater than the number of the downstream flow channels; and / or,

[0011] the cross-sectional area of the upstream flow channel is smaller than the cross-sectional area of the downstream flow channel.

[0012] In some embodiments, the ratio of the number of the upstream flow channels to the number of the downstream flow channels is 10:9 - 24:13; and / or,

[0013] the area ratio of the cross-section of the upstream flow channel to the cross-section of the downstream flow channel is 1 - 1.5.

[0014] In some embodiments, the shapes of the housing, the upstream flow channel, and the cross-section of the upstream flow channel are any one of the following: circular or polygonal.

[0015] In some embodiments, the upstream housing and the downstream housing are detachably connected.

[0016] In some embodiments, the upstream housing is threadedly connected or snap-fitted onto the downstream housing.

[0017] In some embodiments, an O-ring and an O-ring retaining ring are provided between the filter element and the upstream housing; and / or,

[0018] an O-ring gasket is provided between the filter element and the downstream housing.

[0019] In some embodiments, one side of the O-ring retaining ring abuts against the filter element and the O-ring, and the other side abuts against a step inside the upstream housing;

[0020] one side of the O-ring gasket abuts against the filter element, and the other side abuts against a step inside the upstream housing.

[0021] In some embodiments, the thickness of the filter membrane is 20 - 60 microns, and the diameter of the pores in the filter membrane is 0.6 - 1.5 nanometers.

[0022] Compared with the prior art, the present utility model has the following advantages:

[0023] The gas filter provided by the embodiment of the present utility model uses a multi-channel wall-flow filter element which is firm and durable, has a high-precision filter membrane. Due to the inner surface filtration in the multi-channels, the filtration area per unit volume is high, the operation flexibility is large, and the on-line life is long.

[0024] Moreover, the filter element adopts an all-ceramic structure, which can withstand the corrosion and erosion of corrosive gases; the filter membrane in the ceramic has a high precision and is applicable to many fields such as semiconductor manufacturing, biomedicine, and aerospace; the inner surface of the multi-channels is used for filtration, and the filtration area per unit volume is 8-10 times that of the columnar outer surface single-channel filter element, which can withstand the fluctuations of gas flow and solid content, can handle a larger flow rate and a higher solid content. When handling the same gas volume and solid content, the cost of the filter is 1 / 3-1 / 4 of that of the traditional filter, and it has a large operation flexibility and a long on-line life. The external cleaning of the ceramic filter element is simple and easy to operate, and it can be recycled after multiple cleanings, thus extending the on-line life of the filter and having good corrosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic structural diagram of the gas filter provided by an embodiment of the present utility model;

[0026] Figure 2 is a sectional view of the gas filter provided by an embodiment of the present utility model;

[0027] Figure 3 is an exploded view of the gas filter provided by an embodiment of the present utility model;

[0028] Figure 4 is a schematic structural diagram of the filter element provided by an embodiment of the present utility model;

[0029] In the figure, 1 is the upstream housing, 2 is the downstream housing, 3 is the filter element, 31 is the upstream channel, 32 is the downstream channel, 4 is the O-ring, 5 is the O-ring pressing ring, and 6 is the O-shaped gasket. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0030] Many specific details are set forth in the following description in order to provide a thorough understanding of the present utility model. However, the present utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar extensions without departing from the connotation of the present utility model. Therefore, the present utility model is not limited by the specific embodiments disclosed below.

[0031] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as up, down, front, back, left, right, etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation of the present utility model.

[0032] In the description of the present utility model, unless otherwise clearly defined, terms such as "arrangement", "installation", and "connection" should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above terms in the present utility model in combination with the specific content of the technical solution.

[0033] In the description of the present utility model, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model.

[0034] See Figures 1-4 As shown, an embodiment of the present utility model discloses a gas filter, comprising:

[0035] A housing, the housing includes an upstream housing 1 and a downstream housing 2. An air inlet is provided at one end of the upstream housing 1, and an air outlet is provided at one end of the downstream housing 2. The other ends of the upstream housing 1 and the downstream housing 2 are joined to form a hollow chamber extending along the length direction of the housing;

[0036] A filter element 3, disposed in the hollow chamber. The filter element 3 forms a plurality of flow channels, the flow channels extend along the length direction of the housing, one end of the flow channel is blocked to form a blind hole, and the flow channel opening towards the air inlet direction is the upstream flow channel 31, and the flow channel opening towards the air outlet direction is the downstream flow channel 32. A filter membrane is provided on the wall of the upstream flow channel 31, and the gas to be filtered is filtered through the filter membrane and the wall on the upstream flow channel.

[0037] According to the gas filter provided by this embodiment, the multi-channel wall-flow filter element is protected by the housing, and the setting of the filter membrane improves the filtering accuracy; and the filter element contains a plurality of parallel flow channels, and these flow channels are blocked by holes at intervals up and down, so that the filter element is divided into an upstream flow channel and a downstream flow channel; the inner surface of the multi-channel is used for filtering, the filtering area per unit volume is high, the operation flexibility is large, and the on-line service life is long; and the housing structure is simple, and operations such as replacement are easy to achieve.

[0038] In some embodiments, as combined Figure 4 shown, the filter element 3 is a ceramic filter element, and the filter membrane is TiO 2 or ZrO 2 or Al 2 O 3 nanoscale membrane.

[0039] Optionally, the ceramic filter element is integrally formed by a mold.

[0040] Optionally, the filter membrane is formed on the inner wall surface of the upstream flow channel 31 inside the filter element 3 by means of coating. The inner wall surface of the upstream flow channel 31 forms a high-precision filter membrane by methods such as spraying or deposition to become a fine filtration layer, that is, the dust-containing gas inlet side; the downstream flow channel is not sprayed to reduce fluid resistance and becomes the clean gas outlet side. When all the dust-containing fluid passes through the openings in the upstream flow channel 31, through wall flow, the tiny impurities in the gas are intercepted on the inner wall surface of the high-precision upstream flow channel, and the clean gas passes through the channel wall and converges out from the openings of the downstream flow channel 32.

[0041] In addition, the material of the housing can be selected as metal, such as alloy aluminum or stainless steel, etc.

[0042] In some embodiments, the number of the upstream flow channels 31 is greater than the number of the downstream flow channels 32; the cross-sectional area of the upstream flow channel 31 is smaller than the cross-sectional area of the downstream flow channel.

[0043] In some alternative embodiments, the ratio of the number of the upstream flow channels to the number of the downstream flow channels is 10:9 - 24:13. For example, the number of the upstream flow channels is 10 and the number of the downstream flow channels is 9; the number of the upstream flow channels is 24 and the number of the downstream flow channels is 13. Of course, it can also be other values within the above range.

[0044] The area ratio of the cross-section of the upstream flow channel to the cross-section of the downstream flow channel is 1 - 1.5, that is, the cross-sectional area of the upstream flow channel and the cross-sectional area of the downstream flow channel can be the same, or the cross-sectional area of the downstream flow channel is larger than the cross-sectional area of the upstream flow channel. For example, the diameter of the downstream flow channel is 1.2 times the diameter of the upstream flow channel.

[0045] Through the above numerical selection, the amount of filtered gas is further increased, and the filtration precision, efficiency and effect are further improved.

[0046] In some embodiments, the cross-sectional shapes of the housing, the upstream flow channel 31, and the upstream flow channel 32 adopt any one of the following: circular or polygonal, and the polygon is preferably a regular polygon or a rhombus.

[0047] In some embodiments, the upstream housing 1 and the downstream housing 2 are detachably connected.

[0048] In some alternative embodiments, the upstream housing is threadedly connected to the downstream housing, and the two can also be connected together by means of snap connection.

[0049] In some embodiments, in combination Figure 2 and Figure 3 as shown Figure 2 is Figure 1 the cross-sectional view in the A-A direction in Figure 3 isFigure 1 Exploded view. Wherein, an O-ring and an O-ring retaining ring are arranged between the filter element and the upstream housing;

[0050] An O-ring gasket is arranged between the filter element and the downstream housing.

[0051] In some alternative embodiments, one side of the O-ring retaining ring abuts against the filter element and the O-ring, and the other side abuts against a step inside the upstream housing.

[0052] One side of the O-ring gasket abuts against the filter element, and the other side abuts against a step inside the downstream housing.

[0053] The upstream housing is further provided with a stud structure to facilitate threaded connection between the upstream and downstream housings.

[0054] According to Figures 1-3 As shown, both the upstream housing 1 and the downstream housing 2 are stepped, with the cross-section on one side being larger than that on the other side. Threads are provided on the outer sides of the housings with the smaller cross-sections to facilitate installation onto other structures.

[0055] Optionally, the dimensions of each part such as the upstream and downstream housings, steps, diameters, etc. are in the range of several tens of millimeters to several hundreds of millimeters.

[0056] In some embodiments, in combination with Figure 4 As shown, the filter membrane is synthesized by the sol-gel method.

[0057] Specifically, taking the TiO 2 nanofiltration membrane as an example, the nanoscale semiconductor material TiO 2 is synthesized by the sol-gel method. The raw materials used are tetrabutyl titanate (TBOT, AR. solvent), distilled water, absolute ethanol (AR. precursor), and triethanolamine (TEAH 3 , AR. complexing agent). The reactants are Ti(O-C 4 H9) 4 and water, and the phase separation medium is C 2 H 5 OH, which causes Ti(O-C 4 H 9 ) 4 to hydrolyze in C 2 H 5 OH to generate Ti(OH) 4 , and TiO 2 can be obtained after dehydration. In the subsequent heat treatment process, as long as appropriate temperature conditions and reaction times are controlled, rutile-type and anatase-type titanium dioxides can be obtained.

[0058] The overall hydrolysis reaction of tetrabutyl titanate is represented by the following formula, and the hydrolysis product is a titanium ion-containing sol:

[0059] T i(OC 4 H 9 ) 4 +4H 2 O=Ti(OH) 4 +4C 4 H 9 OH

[0060] After the above sol system stands still for a period of time, due to gelation, a stable gel is finally formed. After washing and heat treatment, a nano-titanium dioxide filter membrane with a thickness of 30-40 microns can be deposited on the inner wall of the upstream flow channel, and the diameter of the membrane pores can be 0.9-1 nm; the interception efficiency for 0.002 um particles is 99.9999%, thereby obtaining a gas with ultra-high purity.

[0061] Therefore, in some alternative embodiments, the thickness of the filter membrane is 20-60 microns, and the diameter of the filter pores in the filter membrane is 0.6-1.5 nm; preferably, the thickness of the filter membrane is 30-40 microns, and the diameter of the membrane pores is 0.9-1 nm.

[0062] During the use of the above gas filter, it works in a one-open-one-spare mode. When the pressure difference of one gas filter reaches the set value, the inlet pipeline can be switched to the spare filter, and then the offline filter is opened to remove the filter element for cleaning. The above filter element is made of ceramic material and can be cleaned and reused multiple times.

[0063] In summary, the multi-channel wall-flow ceramic membrane pipeline-type gas filter disclosed by the present invention has the following beneficial effects:

[0064] 1. The online life of the gas filter is longer because of the pure ceramic filter element material with good corrosion resistance; the wall-flow structure has high strength and is strong and durable;

[0065] 2. The multi-channel wall-flow can provide several times the filtration area and can handle a larger flow rate and higher solid content;

[0066] 3. When dealing with the same gas volume and solid content, the cost of the gas filter is 1 / 3-1 / 4 of that of the traditional filter.

[0067] It should be noted that although the present invention is disclosed above with preferred embodiments, it is not used to limit the present invention. Any person skilled in the art can make possible changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be determined by the scope defined by the claims of the present invention.

Claims

1. A gas filter, characterized in that: include: A shell, the shell comprising an upstream shell and a downstream shell, one end of the upstream shell is provided with an air inlet, one end of the downstream shell is provided with an air outlet, the other end of the upstream shell and the other end of the downstream shell are joined to each other to form a hollow chamber extending along the length direction of the shell; A filter element is arranged in the hollow chamber, and the filter element forms a plurality of flow channels, and the flow channels extend along the length direction of the shell. One end of the flow channel is blocked to form a blind hole, and the flow channel opening toward the air inlet direction is the upstream flow channel, and the flow channel opening toward the air outlet direction is the downstream flow channel. A filter membrane is arranged on the wall of the upstream flow channel, and the gas to be filtered is filtered through the filter membrane and the wall on the upstream flow channel.

2. The gas filter according to claim 1, characterized in that The filter element is a ceramic filter element, and the filter membrane is a TiO2, ZrO2 or Al2O3 nano-scale membrane.

3. The gas filter according to claim 1, characterized in that The number of the upstream flow channels is greater than the number of the downstream flow channels; and / or, The cross-sectional area of ​​the upstream flow channel is smaller than the cross-sectional area of ​​the downstream flow channel.

4. The gas filter according to claim 3, characterized in that The ratio of the number of upstream flow channels to the number of downstream flow channels is 10:9-24:13; and / or, The area ratio of the upstream flow channel cross section to the downstream flow channel cross section is 1-1.

5.

5. The gas filter according to claim 1, characterized in that The shell, the upstream flow channel, and the cross-section of the upstream flow channel may be in any of the following shapes: circular or polygonal.

6. The gas filter according to any one of claims 1 to 5, characterized in that: The upstream housing and the downstream housing are detachably connected.

7. The gas filter according to claim 6, characterized in that The upstream housing is threadedly connected or clamped on the downstream housing.

8. The gas filter according to claim 6, characterized in that An O-ring and an O-ring pressure ring are provided between the filter element and the upstream housing; and / or, An O-type gasket is arranged between the filter element and the downstream housing.

9. The gas filter according to claim 8, characterized in that One side of the O-ring pressure ring abuts against the filter element and the O-ring, and the other side abuts against the step in the upstream housing; and / or, One side of the O-type gasket abuts against the filter element, and the other side abuts against the step in the downstream housing.

10. The gas filter according to claim 1 or 2, characterized in that: The thickness of the filter membrane is 20-60 microns, and the diameter of the filter pores in the filter membrane is 0.6-1.5 nanometers.

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