Filtering device, filtering method using filtering device and application of filtering device

Abstract

The invention relates to a filtering device, a filtering method using the filtering device and application thereof, and the filtering device (1) comprises a housing (10) which is provided with a top part (12) provided with an input port (122), a cylinder (13) and a bottom part (16) provided with an output port (162), and the top part (12) and the bottom part (16) are detachably arranged at the end parts, opposite to each other in the axial direction, of the cylinder (13); a filter body (18) arranged in the housing (10); a one-way valve (40), preferably an adjustable one-way valve, which is arranged in a line connecting the inlet opening (122) and the outlet opening (162), the inlet opening (122) being designed to be connectable to a positive pressure source and / or the outlet opening (162) being designed to be connectable to a negative pressure source, the positive pressure source and / or the negative pressure source being able to establish a predetermined pressure difference in the space of the housing separated by the filter body (18).

Description

Technical Field

[0001] The present invention relates to a filtering device, in particular to a filtering device for filtering compounds containing radionuclides. The present invention also relates to a filtering method using the filtering device and its application. Background Art

[0002] In the preparation of urea- 14 C. Barium carbonate - 14 C source material or other 14 C-labeled precursor compound products involve filtration. For the filtration of such compounds containing radionuclides, the transfer and filtration of materials must be carried out in a sealed pipe or reactor. At this time, a filtration device that can effectively ensure the normal filtration of materials, completely isolate the materials from the outside world, and ensure automatic filtration is particularly important. Currently, the continuous closed filtration devices on the market have various problems in the rapid filtration of small amounts of materials containing microparticles and radionuclides, such as easy clogging and low filtration efficiency. Summary of the invention

[0003] The object of the present invention is to provide a filter device which can at least partially solve the above-mentioned problems.

[0004] The filtering device according to the present invention comprises: a shell having a top with an input port, a cylinder and a bottom with an output port, the top and the bottom being detachably arranged at axially opposite ends of the cylinder; a filter body arranged in the shell; a one-way valve, preferably an adjustable one-way valve, arranged in a pipeline connected to the input port and the output port, wherein the input port is designed to be connectable to a positive pressure source and / or the output port is designed to be connectable to a negative pressure source, and the positive pressure source and / or the negative pressure source can establish a predetermined pressure difference in the space of the shell separated by the filter body.

[0005] According to another aspect of the present invention, a filtering method using a filtering device is proposed, which filtering device includes: a top portion provided with an input port, a cylinder and a bottom portion provided with an output port, the top and the bottom portion being detachably arranged at axially opposite ends of the cylinder; a filter body, which is arranged in a shell; a one-way valve, preferably an adjustable one-way valve, which is arranged in a pipeline connected to the input port and the output port, wherein a to-be-filtered substance is introduced into the shell via a positive pressure source connected to the input port and / or via a negative pressure source connected to the output port, and a predetermined pressure difference is established in a space of the shell separated by the filter body via the positive pressure source and / or the negative pressure source.

[0006] According to another aspect of the present invention, it is proposed to use the above-mentioned filtering device for filtering 14 C-labeled precursor compounds, especially urea- 14 C or barium carbonate - 14 Application of C. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] In order to better understand the purpose, features, advantages and functions of the present invention, reference may be made to the preferred embodiments shown in the accompanying drawings. The same reference numerals in the accompanying drawings refer to elements with the same or similar functions. It should be understood by those skilled in the art that the accompanying drawings are intended to schematically illustrate the preferred embodiments of the present invention and have no limiting effect on the scope of the present invention. The components in the drawings are not drawn to scale. The present invention is described below with the help of the accompanying drawings. Among them,

[0008] Figure 1 Schematically shows an embodiment of the filtering device according to the present invention;

[0009] Figure 2 Schematically shows Figure 1 An exploded view of a housing of a filter device; and

[0010] Figure 3 An exploded view of another embodiment of a housing of a filter device according to the present invention is schematically shown. DETAILED DESCRIPTION

[0011] The present invention is further described in detail below in conjunction with the accompanying drawings of the specification. The following description is exemplary and not intended to limit the present invention. Those skilled in the art may think of other ways to implement the present invention based on the preferred embodiments, and other ways also fall within the scope of the present invention.

[0012] In addition, the terms "first", "second", etc. used in the specification are only used to distinguish various objects for the sake of clarity of description, and do not limit the size, quantity or other order of the objects described. The orientation or position relationship indicated by directional terms is based on the orientation or position relationship shown in the drawings, which is only for the purpose of facilitating the description of the present application, and does not indicate or imply that the objects referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application.

[0013] Figure 1 The embodiment of the filter device 1 according to the present invention is schematically shown. The filter device 1 mainly comprises a housing 10, a filter body 18 arranged in the housing 10, a one-way valve 40 and a connecting member. The connecting member is used to connect the above components together, including a joint, a pipeline, etc. The components of the filter device 1 are respectively made of materials that maintain stability and durability in the filtering environment.

[0014] The material to be filtered, such as a solid-liquid mixture, a solid-gas mixture, etc., can be transported into the housing 10, and different components can be separated by the filter body 18. The separated components can be subsequently processed, such as drying or extraction.

[0015] exist Figure 2 It is schematically shown in Figure 1 An exploded view of the housing 10 of the filter device 1. Figure 2 As can be seen in the figure, the housing 10 has a top 12 with an input port 122, a barrel 13 and a bottom 16 with an output port 162. The body 121 of the top 12 and the body 161 of the bottom 16 can be designed as a hemispherical shape. The top 12 and the bottom 16 are detachably arranged at the ends of the barrel 13 that are opposite to each other in the axial direction.

[0016] In order to connect the top 12, the cylinder 13 and the bottom 16 to each other, the top 12, the cylinder 13 and the bottom 16 are exemplarily provided with flanges 123, 140, 163 at the ends facing each other in the assembled state. A plurality of through holes distributed in the circumferential direction, not shown, are provided in the flanges, and the top 12 and the cylinder 13, as well as the cylinder 13 and the bottom 16 are fixed to each other by threaded connectors associated with the corresponding through holes, i.e., a combination of bolts and nuts.

[0017] exist Figure 2 1 shows that the barrel 13 of the housing 10 is formed by a cylindrical member 131, that is, the top 12 and the bottom 16 of the housing 10 are respectively arranged at the axial ends of the cylindrical member 131. However, the barrel 13 of the housing 10 can also be formed by a plurality of cylindrical members, that is, cylindrical sub-segments, which can be connected to each other. For example, Figure 3 It is shown that the cylinder 13 is formed by two cylindrical sub-sections 131 and 132, which are configured with flanges 140 at both ends of the axial direction, and a plurality of through holes distributed in the circumferential direction, which are not shown, are arranged in the flanges, and these cylindrical parts are fixed to each other by threaded connections associated with the corresponding through holes, that is, a combination of bolts and nuts. The plurality of cylindrical sub-sections are preferably designed at least substantially the same, which will be explained below.

[0018] It should be noted that, although it is described above that the components of the housing 10 are fixed to each other by threaded connection, other suitable detachable fixing connection methods may also be selected, such as clamping fixing connection.

[0019] In order to prevent the assembled housing from leaking, a sealing member not shown, such as an O-ring, may be arranged at the connection position of each component of the housing. In addition, preferably, as few openings as possible are provided at each component of the housing.

[0020] The filter body 18 is arranged at a suitable position of the housing. For example, the filter body 18 can be arranged at least one of the cylinder and the bottom, or between the cylinder 13 and the bottom 16.

[0021] The filter body 18 can be in the form of a filter membrane, and the filter membrane can be made of quartz, glass, stainless steel, ceramic or polytetrafluoroethylene, etc., which depends on the type of the object to be filtered. The size of the membrane pores of the filter membrane can be selected according to the object to be filtered. The filter body 18 in the form of a filter membrane can be arranged in a tensioned manner in the housing. When the pressure resistance of the filter body 18, such as the filter membrane, cannot withstand the pressure difference on both sides thereof during operation, the filter body 18 can be arranged in the housing in a supported manner by the carrier 17.

[0022] For example, Figure 2 As shown, the bottom 16 is provided with a groove 164 at its open side facing the cylinder 13, and the carrier 17 can be placed in the groove, wherein the depth and cross section of the groove 164 are consistent with the thickness and cross section of the carrier 17, wherein the area of ​​the cross section is larger than the area of ​​the cross section inside the cylinder, that is, the groove can extend into the area of ​​the flange, so that the carrier 17 in the groove and the filter membrane arranged on the carrier 17 can be held in place by the flange connected together. In the assembled state, the filter body 18 can be on the side of the carrier 17 facing the top 12 of the housing 10. The carrier 17 can be a glass sieve plate, a sand core plate or a stainless steel plate, etc. Of course, the material of the carrier 17 also depends on the type of the object to be filtered.

[0023] In another example, if Figure 3 As shown, when the cylinder 13 is composed of a plurality of cylindrical sub-sections, a groove 142 may be provided on the open side of at least one of the plurality of cylindrical sub-sections facing the top 12 of the housing 10, which may have the same structure as the groove provided at the bottom, and reference may be made to the above description. This enables the volume of the internal space of the cylinder to be appropriately adjusted as required.

[0024] Of course, the filter body may also have other forms and installation methods according to the type and form of the object to be filtered.

[0025] By designing the housing 10 to have a plurality of detachably connected components and detachably mounting the filter and the carrier if necessary, it is particularly convenient to remove the filtered solid components, clean the components of the housing, replace the filter body, etc. In addition, when the solids precipitated from the filtrate adhere to the pores of the carrier, the carrier can also be easily removed for deep cleaning, or the carrier can be directly replaced to quickly achieve filtration between batches.

[0026] In addition, the filter device 1 further comprises a one-way valve 40, preferably an adjustable one-way valve, which is arranged in a pipeline connected to the input port 122 and the output port 162. In this regard, in the filter device 1, the housing 10 and the one-way valve 40 are connected in parallel. To this end, the one-way valve 40 is connected to the input port 122 side of the housing 10 through a pipeline 303 at a first end 401, for example, connected to a corresponding interface of a connector 201 assigned to the input port 122 of the housing 10, and is connected to the output port 162 side of the housing 10 through a pipeline 304 at a second end 402, for example, connected to a corresponding interface of a connector 203 assigned to a collection container 50 connected to the output port 162 of the housing 10, so that the first end 401 of the one-way valve 40 can communicate with the upper space of the two spaces separated by the filter body 18 of the housing 10, that is, the space close to the input port 122, and the second end 402 can communicate with the lower space of the two spaces separated by the filter body 18 of the housing 10, that is, the space close to the output port 162. When the filter device is running, when the pressure difference between the two ends of the one-way valve is greater than a predetermined threshold, the one-way valve opens, which, for example, allows the fluid to flow through the one-way valve 40 (see Figure 1 ), so that the desired pressure can be maintained in the space above the filter body 18 inside the housing. In this regard, constant pressure filtration can be achieved by a one-way valve. When the one-way valve is an adjustable one-way valve, the above pressure inside the housing can also be set by adjusting the adjustable one-way valve, which enables the filtering device to be more widely used to filter different objects to be filtered.

[0027] Figure 1 It is also shown that the collecting container 50 is connected via a connection 203 via a line 302 to a connection 202 assigned to the outlet opening 162 of the housing, and that a further connection 204 is arranged between the connection 203 and the non-return valve 40 .

[0028] The joint 201 has a passage for introducing the to-be-filtered material into the housing through the pipe 301 and a passage for connecting the pipe 303 to the interior space of the housing. The joint 203 has a passage for connecting the interior space of the housing with the interior space of the collection container 50 and a passage for connecting the pipe 305 to the interior space of the collection container 50. The joint 204 is configured so that the pipes 304, 305, 306 are connected to each other.

[0029] Preferably, the input port 122 can be designed to be connected to a positive pressure source, that is, to be applied with positive pressure or to introduce pressurized material to be filtered into the housing; the output port 162 can be designed to be connected to a negative pressure source, that is, to be applied with negative pressure. Here, positive pressure refers to a pressure higher than the external environment, and negative pressure refers to a pressure lower than the external environment. For example, the positive pressure source can be an air pump that applies pressure to a container containing the material to be filtered, and the negative pressure source can be a vacuum pump. By providing a positive pressure source and / or a negative pressure source, it is beneficial to establish a pressure difference on both sides of the filter body in the housing to promote filtration.

[0030] Preferably, the filtering device 1 further comprises a temperature regulating device, that is, a heating and / or cooling and / or heat preservation device, so as to improve the filtering efficiency and filtering effect.

[0031] Preferably, a valve may be arranged in at least one of the above pipelines of the filter device 1 to intervene in the filtering process when necessary, such as interrupting the filtering or maintaining the filter device.

[0032] The following is a preparation of urea- 14 In the form of C 14 The operation of the filtering device 1 according to the present invention is explained by taking the precursor compound labeled with C as an example.

[0033] In filtering urea- 14 C, the urea containing the barium sulfate precipitate with extremely small particle size that needs to be filtered by a microporous filtration membrane 14 The C aqueous solution is pumped into the filtration device via pipeline 301. At this time, positive pressure filtration or negative pressure filtration can be performed in the filtration device, wherein the pore size of the filtration membrane is not greater than 0.45 μm, preferably not greater than 0.1 μm.

[0034] When positive pressure filtration is adopted, the internal space of the housing is first connected to the outside through the pipeline 306 connected to the output port of the housing, and then the pressurized material to be filtered is introduced into the housing 10 through the pipeline 301 via the input port 122, so that the solid-liquid mixture is transferred to the internal space of the housing. At this time, the filtration process begins, that is, the filtrate enters the collection container 50 after passing through the filter membrane. When the pressurized material to be filtered is transported, the gas existing in the space between the filter membrane and the top of the housing inside the housing can be discharged through the one-way valve 40 in the pipelines 303 and 304 connected in parallel with the housing through the pipeline 306 when the pressure value of the gas is greater than the opening pressure of the one-way valve 40, so that the entire feeding process is not affected by the filter membrane and the gas in the upper space in the housing. When feeding, it should be ensured that the material to be filtered in the housing does not exceed the housing volume above the filter membrane to prevent the material to be filtered from entering the pipeline 303. If the filtration is slow and the feeding speed exceeds the filtration speed, intermittent feeding can be adopted. After the filling of the material to be filtered is completed, positive pressure gas, such as liquid protective gas, such as nitrogen, argon, etc., can be continuously introduced into the housing through pipeline 301. During the operation of the filtering device, the pressure in the space formed between the filter membrane and the top of the housing is set and maintained to be at least 5KPa higher than the pressure in the space formed between the filter body and the bottom of the housing, preferably at least 10KPa higher. Under this pressure difference, the material to be filtered and the liquid protective gas are continuously transported into the housing when necessary, and filtered. Here, a one-way valve can be selected or an adjustable one-way valve can be set according to the above-mentioned pressure difference. Constant pressure filtration is achieved through this pressure difference. In this way, the material to be filtered can be repeatedly added for filtration, or cleaning liquid can be added for cleaning, etc. After the filtering and cleaning process is completed, for example, high-purity nitrogen, argon or other suitable gases can be introduced to seal and dry the solid filtered product. After the process is completed, filtrate and solid product can be obtained.

[0035] When negative pressure filtration is adopted, firstly, the pipeline 306 connected to the negative pressure source, such as a vacuum pump, is connected to the inner space of the shell, so that the gas in the inner space of the shell can be extracted to generate a certain vacuum degree in the inner space of the shell, thereby being able to suck the to-be-filtered material, which may be under normal pressure, i.e. atmospheric pressure, into the shell through the pipeline 301. During filtration, the vacuum degree in the shell can be maintained or adjusted by the one-way valve 40 in the pipelines 303 and 304 connected in parallel with the shell. During the operation of the filtration device, the pressure in the space formed between the filter membrane and the top of the shell is set and maintained to be at least 5KPa higher than the pressure in the space formed between the filter body and the bottom of the shell, preferably at least 10KPa higher, and the to-be-filtered material and the liquid protective gas can be continuously transported into the shell under such pressure difference and filtered. Here, due to the one-way valve, the pressure on the input port side of the filter membrane is always greater than the pressure on the output port side, so that the pressure on the output port side is greater than the pressure on the input port side due to misoperation, thereby preventing the filter membrane from being flushed and causing the filtration to fail. After the feeding is completed, negative pressure filtration can be directly performed until the filtration process is completed. The whole process can be completed continuously and automatically, and only the vacuum degree needs to be controlled. Through continuous vacuum, vacuum drying of the solid filtration product can also be achieved at the same time. On the other hand, negative pressure can also be generated in the collection container 50 connected to the housing 10, which also helps to automatically perform the entire filtration process until the filtration process is completed. After the filtration is completed, if necessary, a cleaning liquid can also be sucked from the input port by negative pressure for washing.

[0036] The above-mentioned positive pressure filtration and negative pressure filtration can also be used in combination in the proposed filtering device, that is, the filtered material with positive pressure applied is pressed into the shell 10 through the input port through the pipeline 301, and at the same time, the pipeline 306 connected to the internal space of the shell is connected to a negative pressure source, such as a vacuum pump. Because no matter it is positive pressure filtration, negative pressure filtration or a combination of the two, the one-way valve in the filtering device is opened when the pressure at its first end is greater than the pressure at the second end by a predetermined value, thereby maintaining the set pressure difference in the space on both sides of the filter membrane of the shell, preferably maintaining the pressure in the space formed between the filter membrane and the top of the shell at least 5KPa higher than the pressure in the space formed between the filter body and the bottom of the shell, preferably at least 10KPa higher.

[0037] In the case of a single-layer filter membrane, single-layer filtration can be performed in the filtration device according to the present invention. If the filtration accuracy needs to be further improved, the filtration device can be used Figure 2 shell, thereby achieving multi-layer filtration.

[0038] After the filtration process is completed, the urea in the collection container 50 is 14The aqueous solution can be transferred to a distillation bottle through a pipeline to remove water to obtain solid urea. 14 C API, the entire process is carried out in a sealed environment, which greatly reduces 14 C diffuses into the circulation environment.

[0039] In order to control the amount of material to be filtered added to the housing, a sensor for detecting the filling level of the material to be filtered in the housing may be provided in the housing of the filter device. When the sensor detects that the filling level is higher than a predetermined value, the addition of the material to be filtered may be stopped. The stop may be automatic or manual.

[0040] If the filter device is provided with a temperature control device, it can also be heated, cooled or kept warm by the temperature control device during the filtration and, if necessary, subsequent drying, in order to promote the filtration process and possible drying process.

[0041] The filtering device according to the present invention can also be used for separating, purifying and filtering barium carbonate. 14 C. In this case, the entire filtration process is similar to filtration of urea- 14 C, the barium carbonate- 14 C suspension is transferred from the sedimentation tower to the housing of the filtration device, wherein, during the filtration, the pressure in the space of the housing of the filtration device on the upper side of the filter membrane is set and maintained to be a predetermined value greater than the pressure in the space of the housing on the lower side of the filter membrane, for example, there is a pressure difference of at least 5 KPa, preferably at least 10 KPa, between the two spaces, and continuous automatic transfer and filtration of the material to be filtered are carried out under this pressure difference.

[0042] The following effects can be achieved by the filter device according to the present invention.

[0043] Completely sealed filtration and automated filtration can be achieved. By adjusting the pressure difference between the device for providing the material to be filtered (for example, a temporary storage container for the solid-liquid mixture) and the housing of the filtration device, the material can be transferred. On the other hand, by adjusting the pressure difference between the housing of the filtration device and the collection container, filtration and washing can be achieved.

[0044] It can filter extremely small particles efficiently without increasing the area of ​​the filter membrane, thus reducing the generation of waste.

[0045] It is especially suitable for filtering radioactive materials. According to the properties of the material to be filtered, suitable materials can be selected to manufacture the filter device, including but not limited to stainless steel or other alloys, glass, quartz, ceramics, polytetrafluoroethylene or other plastics.

[0046] Most of the components of the filter device according to the present invention can be reused, and the amount of filter membrane used is small, and a thin filter membrane can meet the requirements, which is particularly important in the field of radioactivity. The device is easy to disassemble and makes cleaning easier.

[0047] The filtering device according to the present invention can filter various forms of filtered objects, for example, it can be used for solid-liquid filtration, solid-gas filtration, etc., such as removing solids by filtration, and removing liquids by filtration.

[0048] The filter device according to the present invention can perform single-layer filtration or multi-layer filtration.

[0049] It should be noted that the features or feature combinations of the device according to the present invention described above and the features and feature combinations mentioned in the drawings and / or only shown in the drawings can be used not only in the corresponding given combination but also in other combinations or alone without departing from the scope of the present invention.

[0050] The present invention has been described through the above embodiments, but it should be understood that the above embodiments are only for the purpose of example and description, and are not intended to limit the present invention to the scope of the described embodiments. It should be understood by those skilled in the art that more variations and modifications can be made according to the teachings of the present invention, and these variations and modifications all fall within the protection scope of the present invention.

Claims

1. A filtering device (1), characterized in that: The filtering device (1) comprises: A housing (10) comprising a top (12) provided with an input port (122), a cylinder (13) and a bottom (16) provided with an output port (162), wherein the top (12) and the bottom (16) are detachably arranged at ends of the cylinder (13) that are opposite to each other in the axial direction; A filter body (18) arranged in the housing (10); a one-way valve (40), preferably an adjustable one-way valve, arranged in a pipeline connected to the input port (122) and the output port (162), The input port (122) is designed to be connected to a positive pressure source and / or the output port (162) is designed to be connected to a negative pressure source, and the positive pressure source and / or the negative pressure source can establish a predetermined pressure difference in the space of the shell separated by the filter body (18).

2. The filtering device (1) according to claim 1, characterized in that The cylinder (13) comprises a plurality of cylinder-shaped subsections which are detachably connected to each other.

3. The filter device (1) according to claim 2, characterized in that: The filter body (18) is preferably held supported by a carrier (17) on the partial section and / or the bottom (16).

4. The filter device (1) according to claim 3, characterized in that The filter body (18) is a filter membrane.

5. The filter device (1) according to claim 4, characterized in that The filter membrane is arranged on a side of the carrier (17) facing the input port (122).

6. The filter device (1) according to claim 4, characterized in that The pore size of the filter membrane is no greater than 0.45 μm, preferably no greater than 0.1 μm.

7. The filter device (1) according to claim 3, characterized in that The filter membrane is made of quartz, glass, stainless steel, ceramic or polytetrafluoroethylene.

8. The filter device (1) according to any one of claims 1 to 7, characterized in that The filtering device (1) is equipped with a temperature regulating device.

9. The filter device (1) according to any one of claims 1 to 7, characterized in that: The filtering device (1) is used to filter 14 C-labeled precursor compounds, especially urea- 14 C or barium carbonate - 14 C, wherein, during operation of the filter device (1), the pressure in the space formed by the shell between the filter body and the top is at least 5 KPa higher than the pressure in the space formed by the shell between the filter body and the bottom, preferably at least 10 KPa higher.

10. The filter device (1) according to any one of claims 1 to 7, characterized in that: The filter device (1) further comprises other pipelines, wherein a valve is arranged in at least one of the pipelines.

11. The filter device (1) according to any one of claims 1 to 7, characterized in that: The filter device (1) has a sensor for detecting the filling level of the substance to be filtered in the housing (10).

12. A filtering method using a filtering device, the filtering device (1) comprising: A housing (10) comprising a top (12) provided with an input port (122), a cylinder (13) and a bottom (16) provided with an output port (162), wherein the top (12) and the bottom (16) are detachably arranged at ends of the cylinder (13) that are opposite to each other in the axial direction; A filter body (18) arranged in the housing (10); a one-way valve (40), preferably an adjustable one-way valve, arranged in a pipeline connected to the input port (122) and the output port (162), The material to be filtered is introduced into the housing (10) via a positive pressure source connected to the input port (122) and / or via a negative pressure source connected to the output port (162), and a predetermined pressure difference is established in the space of the housing separated by the filter body (18) via the positive pressure source and / or the negative pressure source.

13. The filtration device according to any one of claims 1 to 11 is used for filtering 14 C-labeled precursor compounds, especially urea- 14 C or barium carbonate - 14 Application of C.

Images