Device for removing micro-sodium particles in electronic grade sulfuric acid

Abstract

The utility model discloses a device for removing micro sodium particles in electronic grade sulfuric acid, which comprises a tank body, a temporary storage cavity and a liquid discharge cavity, the temporary storage cavity and the liquid discharge cavity are arranged at two ends inside the tank body, a communicating pipe and a circulating pipe which are communicated with the temporary storage cavity and the liquid discharge cavity are respectively arranged inside and outside the tank body, a filter is arranged on the circulating pipe, and an air inlet pipe is arranged at the top of the liquid discharge cavity. And an external nitrogen gas source is communicated in the gas inlet pipe. The effect of improving the filtering efficiency and quality of the electronic-grade sulfuric acid is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of micro-sodium removal, in particular to a device for removing micro-sodium particles in electronic-grade sulfuric acid. Background Art

[0002] Electronic-grade sulfuric acid contains a certain amount of micro-sodium particles. With the upgrading of semiconductor manufacturing processes, higher requirements are placed on the particle size of the micro-sodium in electronic-grade sulfuric acid.

[0003] The existing technology mainly uses a pump to transport electronic grade sulfuric acid and then performs a single filtration, but this filtration method has the following defects:

[0004] 1. The pump produces bubbles, which causes the filter element to become blocked and the filtration efficiency to decrease.

[0005] 2. The filtration efficiency of a single filtration is limited and cannot meet the requirements. Utility Model Content

[0006] The technical problem to be solved by the utility model is low filtering efficiency and poor filtering quality.

[0007] In order to solve the above technical problems, the technical solution adopted by the utility model is: a device for removing trace sodium particles in electronic grade sulfuric acid, comprising a tank body and a temporary storage chamber and a drainage chamber arranged at both ends of the tank body, a connecting pipe and a circulation pipe connecting the temporary storage chamber and the drainage chamber are respectively arranged inside and outside the tank body, a filter is arranged on the circulation pipe, an air inlet pipe is arranged on the top of the drainage chamber, and the air inlet pipe is connected to an external nitrogen gas source.

[0008] Preferably, the connecting pipe and the circulation pipe are respectively provided with a liquid inlet check valve and a liquid outlet check valve, the material flow direction in the circulation pipe is from the drainage cavity to the temporary storage cavity, and the material flow direction in the connecting pipe is opposite to that in the circulation pipe.

[0009] Preferably, the filters are arranged in series on the circulation pipe, and the pore sizes of the filter holes in the filters decrease along the material flow direction in the circulation pipe.

[0010] Preferably, a radar level meter is arranged on the drainage cavity.

[0011] Preferably, the output end of the circulation pipe is located in the temporary storage chamber, and the output end of the circulation pipe is located below the liquid level.

[0012] Preferably, the connecting pipe is located at the bottom of the side wall of the temporary storage chamber, and guide plates are horizontally staggered in the temporary storage chamber, and S-shaped material flow channels are formed by the guide plates respectively. Guide plates are vertically staggered in the drainage chamber, and S-shaped material flow channels are formed by the guide plates respectively. The ends of the material flow channels in the temporary storage chamber and the drainage chamber are connected by the connecting pipe.

[0013] The utility model provides a device for removing trace sodium particles in electronic-grade sulfuric acid. A temporary storage chamber and a drainage chamber are arranged in a tank body, the drainage chamber is pressurized by nitrogen, the electronic-grade phosphoric acid in the drainage chamber is transported to the temporary storage chamber, and the electronic-grade phosphoric acid is filtered by a filter during the transportation process, so that bubbles generated by pump transportation are avoided, thereby improving the filtration efficiency. At the same time, the filter is arranged on a circulation pipe, and multiple filtrations can be performed, thereby improving the filtration efficiency and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0015] Figure 1 It is a schematic structural diagram of an embodiment of the utility model.

[0016] Figure 2 It is a schematic diagram of the internal structure of an embodiment of the utility model.

[0017] In the figure: 1. tank body; 2. temporary storage chamber; 3. drainage chamber; 4. partition; 5. circulation pipe; 6. filter; 7. liquid outlet check valve; 8. liquid inlet check valve; 9. air inlet pipe; 10. radar level gauge; 11. guide plate. DETAILED DESCRIPTION

[0018] like Figure 1 and Figure 2 The utility model provides a device for removing micro-sodium particles in electronic-grade sulfuric acid, comprising a tank body 1 and a temporary storage chamber 2 and a drainage chamber 3 arranged at both ends of the tank body 1, a connecting pipe and a circulation pipe 5 connecting the temporary storage chamber 2 and the drainage chamber 3 are respectively arranged inside and outside the tank body 1, a filter 6 is arranged on the circulation pipe 5, an air inlet pipe 9 is arranged on the top of the drainage chamber 3, and the air inlet pipe 9 is connected to an external nitrogen gas source.

[0019] Two partitions 4 are vertically arranged in the tank body 1 to form a relatively sealed temporary storage chamber 2 and a drainage chamber 3. Both the temporary storage chamber 2 and the drainage chamber 3 are filled with electronic grade sulfuric acid, and some inert gas is retained in the temporary storage chamber 2 to ensure that the electronic grade sulfuric acid in the drainage chamber 3 can enter the temporary storage chamber 2 by squeezing the inert gas, thereby realizing the influx of the electronic grade sulfuric acid.

[0020] When cleaning the trace sodium particles in the electronic-grade sulfuric acid, nitrogen is transported into the drainage chamber 3 through the air inlet pipe 9. The nitrogen squeezes the electronic-grade sulfuric acid in the drainage chamber 3, so that the electronic-grade sulfuric acid enters the temporary storage chamber 2 through the circulation pipe 5. The electronic-grade sulfuric acid is filtered by the filter 6 during the flow in the circulation pipe 5, and the filtering of the electronic-grade sulfuric acid is achieved in the form of pneumatic transportation.

[0021] When the inert gas in the temporary storage chamber 2 is compressed to a certain pressure, the nitrogen in the drainage chamber 3 is discharged through the air inlet pipe 9 or other valves on the tank body 1, and then the connecting pipe is opened to transport the unfiltered part of the electronic grade sulfuric acid in the temporary storage chamber 2 to the drainage chamber 3 through the compressed inert gas in the temporary storage chamber 2, and then the electronic grade sulfuric acid is filtered again through the drainage chamber 3.

[0022] like Figure 1 and Figure 2 As shown, in order to ensure the directional flow of electronic-grade sulfuric acid in the temporary storage chamber 2 and the drainage chamber 3. The connecting pipe and the circulation pipe 5 are respectively provided with a liquid inlet check valve 8 and a liquid outlet check valve 7. The material flow direction in the circulation pipe 5 is from the drainage chamber 3 to the temporary storage chamber 2, and the material flow direction in the connecting pipe is opposite to that in the circulation pipe 5. The flow direction of the electronic-grade sulfuric acid in the connecting pipe and the circulation pipe 5 is controlled by the liquid inlet check valve 8 and the liquid outlet check valve 7, so as to ensure that the electronic-grade sulfuric acid can be filtered in a circulating manner.

[0023] like Figure 1 and Figure 2 The filters 6 are arranged in series on the circulation pipe 5 , and the pore sizes of the filter holes in the filters 6 decrease along the material flow direction in the circulation pipe 5 .

[0024] The pore sizes of the filter 6 decrease from 200 nm to 10 nm, and filters 6 with pore sizes of 200 nm, 100 nm, 50 nm and 10 nm are selected to filter the electronic grade sulfuric acid in sequence.

[0025] like Figure 1 and Figure 2 As shown, in order to monitor the primary filtration amount and avoid excessive pressure in the temporary storage chamber 2, a radar level gauge 10 is arranged on the drainage chamber 3 to monitor the liquid level of the electronic grade sulfuric acid in the drainage chamber 3 through the radar level gauge 10, set the initial liquid level, and when the liquid level difference reaches the set value, the nitrogen in the drainage chamber 3 is discharged, and the electronic grade sulfuric acid in the temporary storage chamber 2 is input into the drainage chamber 3.

[0026] like Figure 1 and Figure 2 As shown. The output end of the circulation pipe 5 is located in the temporary storage chamber 2, and the output end of the circulation pipe 5 is located below the liquid level. By directly transporting the electronic grade sulfuric acid transported by the circulation pipe 5 to below the liquid level of the temporary storage chamber 2, bubbles generated by the impact of the electronic grade sulfuric acid during the transportation process are avoided.

[0027] like Figure 1 and Figure 2The connecting pipe is located at the bottom of the side wall of the temporary storage chamber 2, and the temporary storage chamber 2 is horizontally staggered with guide plates 11, and S-shaped material flow channels are formed by the guide plates 11, and the drainage chamber 3 is vertically staggered with guide plates 11, and S-shaped material flow channels are formed by the guide plates 11, and the ends of the material flow channels in the temporary storage chamber 2 and the drainage chamber 3 are connected by the connecting pipe.

[0028] By arranging the guide plate 11, the electronic grade sulfuric acid in the temporary storage chamber 2 and the drainage chamber 3 can flow in a directional manner, and the circulation pipe 5 is transported to the end of the material flow channel in the temporary storage chamber 2. The connecting pipe is connected to the other end of the material flow channel to realize the directional flow of the material, and the material is filtered in sequence to ensure the filtration efficiency; the material flow form in the drainage chamber 3 is the same as that in the temporary storage chamber 2.

Claims

1. A device for removing trace sodium particles from electronic grade sulfuric acid, characterized in that: The invention comprises a tank body (1) and a temporary storage chamber (2) and a liquid discharge chamber (3) arranged at two ends of the tank body (1). A connecting pipe and a circulation pipe (5) connecting the temporary storage chamber (2) and the liquid discharge chamber (3) are respectively arranged inside and outside the tank body (1). A filter (6) is arranged on the circulation pipe (5). An air inlet pipe (9) is arranged at the top of the liquid discharge chamber (3). The air inlet pipe (9) is connected to an external nitrogen gas source.

2. The device for removing trace sodium particles in electronic grade sulfuric acid according to claim 1, characterized in that: The connecting pipe and the circulation pipe (5) are respectively provided with a liquid inlet check valve (8) and a liquid outlet check valve (7); the material flow direction in the circulation pipe (5) is from the discharge chamber (3) to the temporary storage chamber (2); and the material flow direction in the connecting pipe is opposite to that in the circulation pipe (5).

3. The device for removing micro-sodium particles in electronic grade sulfuric acid according to claim 2, characterized in that: The filters (6) are arranged in series on the circulation pipe (5), and the pore sizes of the filter holes in the filters (6) decrease along the material flow direction in the circulation pipe (5).

4. The device for removing trace sodium particles in electronic grade sulfuric acid according to claim 1, characterized in that: A radar liquid level meter (10) is arranged on the liquid discharge cavity (3).

5. The device for removing trace sodium particles in electronic grade sulfuric acid according to claim 1, characterized in that: The output end of the circulation pipe (5) is located in the temporary storage chamber (2), and the output end of the circulation pipe (5) is located below the liquid level.

6. The device for removing trace sodium particles in electronic grade sulfuric acid according to claim 5, characterized in that: The connecting pipe is located at the bottom of the side wall of the temporary storage chamber (2); guide plates (11) are arranged horizontally and staggered in the temporary storage chamber (2), and S-shaped material flow channels are formed by the guide plates (11); guide plates (11) are arranged vertically and staggered in the drainage chamber (3), and S-shaped material flow channels are formed by the guide plates (11); the ends of the material flow channels in the temporary storage chamber (2) and the drainage chamber (3) are connected by the connecting pipe.

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