Automatic sampling device for anhydrous hydrogen fluoride

Abstract

The utility model relates to sampling device technical field, concretely is an automatic sampling device of anhydrous hydrogen fluoride, including sampling circuit module, sampling module and step -by -step control unit, sampling circuit module is equipped with pre -flow circulation replacement structure, and sampling module realizes automatic opening and closing bottle plug through motor drive's displacement platform and manipulator, and the residual is removed in combination with negative pressure after sampling, realizes the automation sampling of nobody's manual contact, sample pollutionlessness, risk early warning all the way, solves the defect that the present technical sampling safety hidden danger is big.

Description

Technical Field

[0001] This utility model relates to the field of sampling device technology, specifically to an automatic sampling device for anhydrous hydrogen fluoride. Background Technology

[0002] With the rapid development of science and technology, the fluorochemical industry is playing an increasingly significant supporting role in emerging industries such as aerospace, information and communication, life sciences, and new energy, as well as in traditional industries promoting sustainable development. Anhydrous hydrogen fluoride is a basic raw material for the fluorochemical industry, and electronic-grade hydrofluoric acid (HF aqueous solution) is an indispensable raw material for cutting-edge fields such as chip manufacturing, photovoltaic power generation, and power batteries. Therefore, frequent sampling of anhydrous hydrogen fluoride is necessary. However, hydrogen fluoride is an inorganic acid with extremely reactive chemical properties. Under normal conditions, it is a colorless, toxic gas with an irritating odor. It has very strong hygroscopic properties and produces white fumes upon contact with air. It can also react with materials such as metals. Therefore, it is necessary to design a device for sampling anhydrous hydrogen fluoride to eliminate the dangers during the sampling process.

[0003] Existing hydrogen fluoride sampling methods rely on sampling devices. For example, patent CN217331767U discloses a closed sampling system for anhydrous hydrogen fluoride, which features a simple and novel structure, a closed and visualized operating box, and an exhaust gas treatment system to achieve quantitative sampling of anhydrous hydrogen fluoride. However, this existing technology only solves the problem of closed sampling. During operation, the system does not automate the opening and closing of the sampling bottle stopper, requiring manual operation. This method has the following drawbacks: First, although the operator is outside the box, they still come into direct contact with the high-risk medium while wearing gloves, posing a risk of leakage due to broken gloves, operational errors, or inadequate sealing, potentially leading to poisoning and corrosion accidents. Second, at the moment of sampling completion, opening the operating box to remove the sampling bottle, and before manually tightening the cap, the sampling bottle opening is easily exposed to the air, causing moisture and dust in the air to contaminate the sample, affecting the accuracy of the analysis, and even posing a danger due to the sample absorbing moisture and releasing heat. Third, the lack of a pre-flow replacement structure in the pipeline means that residual air and moisture in the sampling branch can easily react with anhydrous hydrogen fluoride, contaminating the sample and potentially causing pipeline corrosion.

[0004] Therefore, there is an urgent need for a sampling device that can automate and ensure safety throughout the entire process of "opening the lid, taking a sample, and closing the lid". Utility Model Content

[0005] The purpose of this invention is to address the safety issues associated with anhydrous hydrogen fluoride sampling in existing technologies. This invention provides an automatic sampling device for anhydrous hydrogen fluoride that automates the entire process from opening the cap, sampling, and closing the cap, completely eliminating contact between personnel and hazardous media, and ensuring the purity and authenticity of the sample.

[0006] To solve the above problems, the technical solution adopted by this utility model is an automatic sampling device for anhydrous hydrogen fluoride, which is installed on the main pipeline for transporting anhydrous hydrogen fluoride, and includes a sampling circuit module, a sampling module, and a step control unit.

[0007] The sampling circuit module includes a sampling branch connected in parallel with the main pipeline. Along the direction of medium flow, the sampling branch is provided with a first isolation valve resistant to hydrofluoric acid corrosion, a three-way sampling valve, and a second isolation valve. The third passage of the sampling valve is the sampling port. The sampling module includes a displacement platform driven by a first drive motor and a bottle stopper manipulator driven by a second drive motor; the displacement platform can move along a preset guide rail between a preparation position, a sampling position, and an exit position; a sampling bottle holder is provided on the displacement platform; the bottle stopper manipulator is used to perform gripping, loosening, and placing of the bottle stopper of the sampling bottle; The step-by-step control unit is electrically connected to the first isolation valve, the second isolation valve, the sampling valve, the first drive motor, and the second drive motor.

[0008] Furthermore, the sampling valve and sampling module are housed in a sealed enclosure. The outer shell of the enclosure is made of stainless steel, and the inner wall of the enclosure is coated with polytetrafluoroethylene. An observation window and an operation window are provided on the front side of the enclosure.

[0009] Furthermore, it also includes an exhaust gas absorption pipe, one end of which is connected to the top of the sealed box, and the other end is connected to an alkaline absorption tower.

[0010] Furthermore, it also includes a negative pressure pipe, one end of which is connected to the sampling branch between the first isolation valve and the sampling valve, and the other end is connected to a negative pressure source.

[0011] Furthermore, the stopper of the sampling bottle is a threaded sealing stopper made of polytetrafluoroethylene.

[0012] In this solution, the step-by-step control unit is a manual operation panel containing multiple independent control buttons, with each button corresponding to control an actuator.

[0013] Compared with existing technologies, the beneficial effects of this solution are: 1. Operational safety: This invention uses a sealed box and bottle stopper to operate the robotic arm. Operators do not need to directly contact the sampling bottle or medium. All operations can be completed through the step-by-step control unit, which fundamentally eliminates safety risks.

[0014] 2. The sampling branch undergoes a dual pretreatment process of "pre-flow replacement + negative pressure removal" to thoroughly remove residual air and moisture from the branch, thus avoiding sample contamination. At the same time, the opening and closing of the bottle stopper and the sampling process are all completed within a sealed box, with no exposure of the sampling bottle opening to air, effectively preventing moisture and dust contamination.

[0015] 3. Clear structure and easy to implement: Each module has a clear function, and the components used, such as the stopper manipulator and the displacement platform, are all existing mature technologies. The entire device has a specific structure and is easy to manufacture and implement. Attached Figure Description

[0016] Figure 1 This is an overall structural diagram of an automatic sampling device for anhydrous hydrogen fluoride in fertilizer preparation according to this utility model.

[0017] In the diagram: 1-Main pipeline; 2-Sampling branch; 3-First isolation valve; 4-Sampling valve; 5-Second isolation valve; 6-Sampling port; 7-Displacement platform; 8-Bottle stopper manipulator; 9-Sampling bottle; 10-Sealed box; 11-Negative pressure pipe; 12-Tail gas absorption pipe. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Implementation, for example, attached Figure 1 As shown: This embodiment is an automatic sampling device for anhydrous hydrogen fluoride in fertilizer preparation, including a sampling circuit module, a sampling module, and a step control unit.

[0020] The sampling circuit module includes a sampling branch 2 connected in parallel with the main pipeline 1. Along the direction of medium flow, the sampling branch 2 is equipped with a first isolation valve 3, a sampling valve 4, and a second isolation valve 5 that are resistant to hydrofluoric acid corrosion. The sampling valve 4 is a three-way ball valve. Its first passage is connected to the first isolation valve 3, its second passage is connected to the second isolation valve 5, and its third passage serves as a sampling port 6 for delivering anhydrous hydrogen fluoride to the sampling bottle 9.

[0021] Before sampling, hydrogen fluoride is allowed to circulate in sampling branch 2 and flow into main pipeline 1. The procedure is as follows: First, open the first isolation valve 3, the second passage of sampling valve 4, and the second isolation valve 5, allowing liquid hydrogen fluoride to flow out of main pipeline 1. A portion of this liquid enters sampling branch 2, passing sequentially through the first isolation valve 3, the second passage of sampling valve 4, and the second isolation valve 5, finally flowing into main pipeline 1. After flowing for a certain period, the second passage is closed, and the third passage of sampling valve 4 is opened for sampling. The rationale for this design is that when sampling branch 2 is idle for a long time, air, moisture, or residual media from previous sampling may remain inside. Anhydrous hydrogen fluoride will generate corrosive fumes when it comes into contact with water. Fog can also affect sample purity. Pre-flowing the sampling branch 2 for a period of time can flush these impurities back into the tank, filling the pipeline with pure hydrogen fluoride and preventing impurities from mixing with the newly taken sample. This also prevents pipeline corrosion or leakage risks caused by impurities. In addition, it ensures smooth sampling. There may be a pressure difference between the main pipeline 1 and the sampling branch 2. Direct sampling can cause a sudden change in the medium flow rate, or even "sample splashing" or inaccurate sampling. Circulating flow can form a closed loop between the main pipeline 1, the sampling branch 2, and the tank, gradually stabilizing the pressure and keeping the medium flow rate uniform. This results in a more stable fluid state and more reliable data during subsequent sampling.

[0022] The sampling module is the core of the entire device, used to realize the displacement of the sampling bottle 9 and the automatic opening and closing of the bottle stopper. It includes a displacement platform 7 driven by a first drive motor and a bottle stopper manipulator 8 driven by a second drive motor. The displacement platform 7 can move precisely on the guide rail, moving between the "preparation position", "sampling position" and "exit position". The "preparation position" is the starting position, used to receive and place the empty sampling bottle 9. The bottle stopper manipulator 8 completes the unscrewing and retraction of the bottle stopper here. The "sampling position" is the working position, located directly below the sampling port 6. At this position, the mouth of the sampling bottle 9 is coaxially aligned with the sampling port 6 to ensure stable medium flow. After sampling, the bottle stopper manipulator 8 closes the cap here. The "exit position" is the finishing position, away from the sampling port 6 and within the reach of the box operation window. This position is used for the operator to remove the sampling bottle 9 after sampling. A bottle holder is installed on the displacement platform 7 to fix the sampling bottle 9 with a polytetrafluoroethylene stopper. The stopper manipulator 8 is used to grasp, loosen, and place the stopper of the sampling bottle 9. This manipulator is a mature manipulator in the existing technology, and will not be described in detail here.

[0023] The sealed enclosure 10 provides a safe environment isolated from the outside world for the operation and sampling process of the stopper-operating robot 8. The outer shell of the sealed enclosure 10 is made of 316L stainless steel, and the inner wall is coated with polytetrafluoroethylene. The front is equipped with an anti-fog plexiglass observation window and an operation window, and an HF concentration sensor is embedded inside. When the hydrogen fluoride concentration in the enclosure exceeds the standard, the operator shuts off all valves and starts the tail gas absorption pipe 12 to draw the residual gas in the enclosure into the alkaline absorption tower to avoid the risk of leakage.

[0024] The device also includes a negative pressure tube 11, with a negative pressure control valve connected in series on the negative pressure tube 11. Before sampling, the air in the branch is removed by vacuuming for 3-5 seconds, and after sampling, the residual hydrogen fluoride is recovered by vacuuming for 5-8 seconds.

[0025] The operation of this utility model is based on the structure of the device, and is completed by the operator sequentially starting each component through the step-by-step control unit. The step-by-step control unit is electrically connected to the first isolation valve, the second isolation valve, the sampling valve, the first drive motor, and the second drive motor.

[0026] Workflow: 1. Preparation stage (pipeline pretreatment + empty bottle loading): 1.1 Pipeline Pretreatment: The operator opens the negative pressure control valve, starts the negative pressure source (vacuum pump), and evacuates the sampling branch 2 through the negative pressure pipe 11 for 5 seconds to remove residual air and moisture in the branch; then closes the negative pressure control valve, opens the first isolation valve 3, the second passage of the sampling valve 4, and the second isolation valve 5. At this time, part of the anhydrous hydrogen fluoride in the main pipeline 1 flows into the sampling branch 2, passes through the first isolation valve 3, the second passage of the sampling valve 4, and the second isolation valve 5 in sequence, and finally flows back to the main pipeline 1, realizing the pre-flow replacement of the sampling branch 2 (flow time 60 seconds), ensuring that the branch is filled with pure anhydrous hydrogen fluoride and avoiding contamination of subsequent samples.

[0027] 1.2 Empty bottle loading and cap opening: The operator places the empty sampling bottle 9 with the bottle stopper into the bottle holder of the displacement platform 7 in the operating window of the sealed box 10, and then presses the button to control the "bottle stopper operation robot 8". The robot grabs and unscrews the bottle stopper according to the preset action and moves it aside.

[0028] 2. Docking Phase: The operator presses the button to control the "first drive motor", which drives the displacement platform 7 to move to the "sampling position". At this time, the mouth of the sampling bottle 9 is aligned with the sampling port 6 on the same axis to ensure that anhydrous hydrogen fluoride can flow into the sampling bottle 9 stably.

[0029] 3. Sampling: The operator presses the button to close the second passage of sampling valve 4 and simultaneously opens the button to open the third passage of sampling valve 4. Anhydrous hydrogen fluoride in the main pipeline 1 flows into the sampling bottle 9 through the sampling branch 2, the first isolation valve 3, the third passage of sampling valve 4, and the sampling port 6. After the required sampling volume is reached, the operator presses the buttons to close "sampling valve 4" and "first isolation valve 3" in sequence.

[0030] 4. Close the lid: After the sampling phase is completed, the operator presses the control button of the bottle stopper manipulator 8 again, causing it to tighten the bottle stopper onto the mouth of the sampling bottle 9. After the cap is closed, the operator opens the valve of the exhaust gas absorption pipe 12, introducing any trace amount of hydrogen fluoride gas that may have leaked from the sealed chamber 10 into the alkaline absorption tower (sodium hydroxide solution concentration 10%), with an absorption time of 30 seconds to ensure that there are no residual harmful gases in the chamber.

[0031] 5. Exit: After the exhaust gas treatment is completed, the operator controls the displacement platform 7 to move to the "exit position"; after the displacement platform 7 is in place, the operator can open the sealed operating window of the sealed box 10 and safely take out the sealed sampling bottle 9 (the stopper of the sampling bottle 9 has been tightened, and there is no risk of medium leakage).

[0032] The above descriptions are merely embodiments of this utility model, and common knowledge regarding specific structures and characteristics is not elaborated upon here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of this utility model, and these should also be considered within the scope of protection of this utility model. These modifications will not affect the effectiveness of the implementation of this utility model or the practicality of the patent. The scope of protection claimed in this application shall be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. An automatic sampling device for anhydrous hydrogen fluoride, installed on the main pipeline for transporting anhydrous hydrogen fluoride, characterized in that: Includes a sampling loop module, a sampling module, and a step control unit; The sampling circuit module includes a sampling branch connected in parallel with the main pipeline. Along the direction of medium flow, the sampling branch is provided with a first isolation valve resistant to hydrofluoric acid corrosion, a three-way sampling valve, and a second isolation valve. The third passage of the sampling valve is the sampling port. The sampling module includes a displacement platform driven by a first drive motor and a bottle stopper manipulator driven by a second drive motor; the displacement platform can move along a preset guide rail between a preparation position, a sampling position, and an exit position; a sampling bottle holder is provided on the displacement platform; the bottle stopper manipulator is used to perform gripping, loosening, and placing of the bottle stopper of the sampling bottle; The step-by-step control unit is electrically connected to the first isolation valve, the second isolation valve, the sampling valve, the first drive motor, and the second drive motor.

2. The automatic sampling device for anhydrous hydrogen fluoride according to claim 1, characterized in that: The sampling valve and sampling module are housed in a sealed enclosure. The outer shell of the enclosure is made of stainless steel, and the inner wall of the enclosure is coated with polytetrafluoroethylene. An observation window and an operation window are provided on the front side of the enclosure.

3. The automatic sampling device for anhydrous hydrogen fluoride according to claim 2, characterized in that: It also includes an exhaust gas absorption pipe, one end of which is connected to the top of the sealed box, and the other end is connected to an alkaline absorption tower.

4. The automatic sampling device for anhydrous hydrogen fluoride according to claim 1, characterized in that: It also includes a negative pressure pipe, one end of which is connected to the sampling branch between the first isolation valve and the sampling valve, and the other end is connected to a negative pressure source.

5. The automatic sampling device for anhydrous hydrogen fluoride according to claim 1, characterized in that: The stopper of the sampling bottle is a threaded sealing stopper made of polytetrafluoroethylene.

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