Hydrofluoric acid diluting device and diluting process thereof

Abstract

The invention discloses a hydrofluoric acid diluting device and a diluting process thereof, and relates to the technical field of industrial raw materials. The hydrofluoric acid diluting device comprises an absorption tower, an absorption circulating pump, a cooler, a distributor, a liquid level meter, a regulating valve, a flowmeter and a finished product acid concentration meter, anhydrous hydrogen fluoride is connected to the top of the absorption tower through a pipeline and uniformly distributed into the tower through a distributor (distributor 1), an upper-stage distributor and a lower-stage distributor are arranged in the absorption tower, the upper-stage distributor receives the anhydrous hydrogen fluoride, and the lower-stage distributor receives the finished product acid concentration meter. According to the hydrofluoric acid diluting device and the hydrofluoric acid diluting process, the anhydrous hydrogen fluoride and diluting water / dilute acid are mixed in the absorption tower, the anhydrous hydrogen fluoride is mixed with the circulating acid in the lower-stage distributor after being distributed by the distributors, and the circulating acid is mixed with the circulating acid in the lower-stage distributor. Therefore, stable operation of the device is guaranteed, and the problem of unstable product quality caused by flow fluctuation is effectively avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of industrial raw materials, and particularly relates to a hydrofluoric acid dilution device and its dilution process. Background Art

[0002] Hydrofluoric acid, as an important industrial raw material, is widely used in many fields and is usually prepared from anhydrous hydrogen fluoride and water / dilute acid. However, there are many problems in the existing hydrofluoric acid dilution process: on the one hand, due to the high dilution heat of hydrogen fluoride and its extremely low vaporization temperature, during the mixing process, especially when preparing high-concentration hydrofluoric acid, anhydrous hydrogen fluoride is extremely easy to vaporize, which will cause fluctuations in the system flow rate, making the control difficult, the product quality unstable, and the concentration fluctuating significantly. On the other hand, there are often a small amount of gas phases in the product, which brings difficulties to the accurate measurement of the product concentration, and thus it is difficult to achieve automatic control. Currently, the intermittent configuration method is mostly used, which has low production efficiency and requires stirring during the production process. However, the stirring device can only be coated with anti-corrosion by spraying. Given the high permeability of fluoride ions, the equipment is extremely easy to be corroded, resulting in a high maintenance rate, greatly increasing the production cost, reducing the production efficiency, and restricting the development of the hydrofluoric acid-related industries. Summary of the Invention

[0003] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art, and provide a hydrofluoric acid dilution device and its dilution process, which can solve the problem of unstable product quality.

[0004] To achieve the above purpose, the present invention provides the following technical solution: A hydrofluoric acid dilution device includes an absorption tower, an absorption circulation pump, a cooler, a distributor, a liquid level gauge, a regulating valve, a flow meter, and a finished acid concentration meter. Anhydrous hydrogen fluoride is connected to the top of the absorption tower through a pipeline and evenly enters the tower through the distributor (distributor 1). There are two levels of distributors in the absorption tower. The upper distributor receives anhydrous hydrogen fluoride, and the lower distributor is used for mixing anhydrous hydrogen fluoride with the circulating acid;

[0005] The absorption tower is filled with packing, and the mixed acid solution flows through the packing for secondary mixing and dilution;

[0006] The bottom of the absorption tower is connected to the inlet of the absorption circulation pump through a pipeline to transport the mixed acid solution in the tower out;

[0007] A liquid level gauge is installed on the side of the absorption tower to monitor the liquid level in the tower, and a regulating valve is also provided on the absorption tower.

[0008] Preferably, the inlet of the absorption circulation pump is connected to the bottom of the absorption tower, and the outlet is connected to the inlet of the cooler through a pipeline.

[0009] Preferably, the function of the absorption circulation pump is to pump out the mixed acid solution in the absorption tower, pressurize and transport it to the cooler for cooling.

[0010] Preferably, the absorbed tail gas is discharged from the lower part of the absorption tower.

[0011] Preferably, the dilution water / dilute acid is added to the latter section of the pipeline from the cooler outlet to the absorption tower, and the addition amount is precisely controlled by a flow meter and a regulating valve.

[0012] Preferably, after the dilution water / dilute acid is added, it is mixed with the circulating acid and enters the absorption tower together to be mixed with anhydrous hydrogen fluoride.

[0013] Preferably, a hydrofluoric acid dilution process includes the following steps. S1 Process preparation:

[0014] Device inspection and preparation: Conduct a comprehensive inspection on the hydrofluoric acid dilution device composed of an absorption tower, an absorption circulation pump, a cooler, a distributor, a liquid level gauge, a regulating valve, a flow meter, and a finished acid concentration meter to ensure that the inside of the absorption tower is clean, without impurity residues, the packing is complete and evenly distributed; check the sealing performance and impeller condition of the absorption circulation pump to ensure its normal operation; confirm that the cooler pipeline has no leakage and the heat exchange effect is good. At the same time, calibrate all measuring instruments, such as liquid level gauges, flow meters, and finished acid concentration meters, so that their measurement accuracy meets the process requirements;

[0015] Raw material preparation: Prepare high-purity anhydrous hydrogen fluoride and dilution water / dilute acid that meet the process requirements. Detect the purity of anhydrous hydrogen fluoride to ensure that its impurity content is within the allowable range to avoid impurities affecting the quality of the diluted hydrofluoric acid. Calculate the required amounts of anhydrous hydrogen fluoride and dilution water / dilute acid according to the target dilution concentration;

[0016] S2 Initial cycle establishment:

[0017] Add dilution water / dilute acid: Add an appropriate amount of dilution water / dilute acid to the absorption tower, start the absorption circulation pump, and make the dilution water / dilute acid form a cycle among the absorption tower, the absorption circulation pump, and the cooler. During the circulation process, check whether there is any leakage at each connection part to ensure good system sealing;

[0018] Start the cooling system: Start the cooling medium circulation of the cooler and set the cooling temperature. The setting of the cooling temperature only needs to consider removing the reaction heat;

[0019] S3 Hydrogen fluoride introduction and preliminary dilution:

[0020] Slowly introduce anhydrous hydrogen fluoride: After the internal circulation of the absorption tower is stably established and the cooling system is operating normally, slowly introduce anhydrous hydrogen fluoride. The anhydrous hydrogen fluoride is evenly distributed into the absorption tower through the distributor and is preliminarily mixed with the circulating acid at the lower distributor. Control the introduction speed of anhydrous hydrogen fluoride to avoid overly violent reactions caused by too fast introduction, resulting in temperature and pressure fluctuations;

[0021] Real-time monitoring and regulation: During the process of introducing anhydrous hydrogen fluoride, use a finished acid concentration meter to monitor the concentration change of the acid liquid in the absorption tower in real time. At the same time, monitor the liquid temperature in the tower through a thermometer. According to the concentration and temperature changes, finely adjust the introduction speed of anhydrous hydrogen fluoride and the cooling capacity of the cooler to maintain the stable progress of the reaction in the absorption tower;

[0022] S4 Secondary mixing and dilution enhancement:

[0023] Packing section mixing: The acid liquid after preliminary mixing enters the packing section of the absorption tower for secondary mixing and dilution. The presence of the packing increases the gas-liquid contact area and strengthens the mixing effect of anhydrous hydrogen fluoride and dilution water / dilute acid. In the packing section, anhydrous hydrogen fluoride further dissolves and fully reacts with the dilution water / dilute acid, making the acid liquid concentration more uniform;

[0024] Absorption tail gas treatment: The absorption tail gas is discharged from the lower part of the absorption tower and can be processed subsequently according to the actual situation. For example, recover the unreacted hydrogen fluoride in it through a tail gas absorption device to reduce raw material waste and environmental pollution;

[0025] S5 Finished acid concentration regulation and discharge:

[0026] Concentration control: When it is detected that the concentration of the finished acid is close to the set value, precisely adjust the flow rate of the dilution water / acid through a flow meter and a regulating valve so that it enters the absorption tower at a set flow rate after mixing with the circulating acid. At the same time, use the outlet concentration meter and the HF pipeline regulating valve to automatically control the HF flow rate to ensure that the concentration of the finished acid in the absorption tower is stable at the set value;

[0027] Liquid level control and discharge: As the dilution water and HF are continuously added, the liquid level in the absorption tower gradually rises. When the liquid level reaches the set value, under the action of the liquid level meter and the regulating valve, the finished acid is automatically discharged from the absorption tower to maintain a constant liquid level in the absorption tower. The discharged finished acid enters the subsequent storage or use link;

[0028] S6 System maintenance and optimization:

[0029] Regular detection and maintenance: During the process of the process operation, regularly detect and maintain the device, check the wear condition of the packing in the absorption tower, and replace it in time if necessary; maintain the absorption circulation pump, such as changing the lubricating oil and checking the mechanical seal; regularly calibrate the measuring instruments to ensure their measurement accuracy;

[0030] Data recording and analysis: Record various data during the process operation, such as temperature, pressure, flow rate, concentration. Through the analysis of these data, promptly discover abnormal situations in the process operation and optimize and adjust the process parameters to improve the stability of the hydrofluoric acid dilution process and the product quality.

[0031] Compared with the prior art, the beneficial effects of the present invention are:

[0032] 1. The hydrofluoric acid dilution device and its dilution process have high operation stability: For the hydrofluoric acid dilution device and its dilution process of the present invention, anhydrous hydrogen fluoride and dilution water / dilute acid are mixed inside the absorption tower. After being distributed by the distributor, anhydrous hydrogen fluoride is mixed with the circulating acid at the lower distributor. This mixing method ensures that the small amount of gasification of anhydrous hydrogen fluoride will not cause fluctuations in the pipeline flow rate. Since the mixing occurs inside the tower, the gasified anhydrous hydrogen fluoride will not affect the flow rate in the conveying pipeline, thus ensuring the stable operation of the device and effectively avoiding the problem of unstable product quality caused by flow rate fluctuations.

[0033] 2. The hydrofluoric acid dilution device and its dilution process enable accurate concentration measurement and facilitate automatic control: The finished acid enters the bottom of the tower through the packing section of the absorption tower. The packing section can effectively separate the gas in the finished acid, enabling accurate measurement of the concentration of the finished acid. Based on the accurate concentration measurement, combined with equipment such as flow meters, regulating valves, and finished acid concentration meters, automatic control of the system can be achieved, precisely adjusting the flow rates of dilution water / acid and anhydrous hydrogen fluoride to ensure that the concentration of the finished acid is stable at the set value.

[0034] 3. The hydrofluoric acid dilution device and its dilution process are convenient for commissioning and coupling with subsequent processes: The initial commissioning of the system can be carried out in the device. Even if unqualified products occur during the commissioning process, they will not enter the subsequent processes, avoiding the impact of unqualified products on subsequent production links. At the same time, the device and process are convenient for coupling with subsequent processes, enabling better adaptation to the entire production process and improving the coherence and efficiency of production. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] The present invention will be further described below in conjunction with the drawings and embodiments:

[0036] Figure 1 It is a schematic flow structure diagram of a hydrofluoric acid dilution device of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0037] This part will describe the specific embodiments of the present invention in detail. The preferred embodiments of the present invention are shown in the drawings. The role of the drawings is to supplement the description in the text part of the specification, enabling people to intuitively and vividly understand each technical feature and the overall technical solution of the present invention. However, it should not be construed as a limitation on the protection scope of the present invention.

[0038] In the description of the present invention, 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. It is only for the convenience of describing the present invention 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 therefore should not be construed as a limitation on the present invention.

[0039] In the description of the present invention, terms such as "greater than", "less than", "exceeding", etc. are understood not to include the number itself, while terms such as "above", "below", "within", etc. are understood to include the number itself. If there is a description of "first" and "second", it is only for the purpose of distinguishing technical features and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features or the sequence relationship of the indicated technical features.

[0040] In the description of the present invention, unless otherwise clearly defined, terms such as "set", "installed", "connected", etc. 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 invention in combination with the specific content of the technical solution.

[0041] Please refer to Figure 1 , the present invention provides a technical solution: a hydrofluoric acid dilution device, including an absorption tower, an absorption circulation pump, a cooler, a distributor, a liquid level gauge, a regulating valve, a flow meter, and a finished acid concentration meter;

[0042] Among them, anhydrous hydrogen fluoride is connected to the top of the absorption tower through a pipeline and evenly distributed into the tower through a distributor (distributor 1);

[0043] There are two levels of distributors in the absorption tower. The upper distributor receives anhydrous hydrogen fluoride, and the lower distributor is used for mixing anhydrous hydrogen fluoride with the circulating acid;

[0044] The absorption tower is filled with packing, and the mixed acid solution flows through the packing for secondary mixing and dilution;

[0045] The bottom of the absorption tower is connected to the inlet of the absorption circulation pump through a pipeline to transport the mixed acid solution in the tower out;

[0046] The absorption tail gas is discharged from the lower part of the absorption tower;

[0047] A liquid level gauge is installed on the side of the absorption tower to monitor the liquid level in the tower. A regulating valve is also provided on the absorption tower to control the discharge of the finished acid when the liquid level gauge monitors that the liquid level reaches the set value;

[0048] Among them, the inlet of the absorption circulation pump is connected to the bottom of the absorption tower, and the outlet is connected to the inlet of the cooler through a pipeline;

[0049] The function of the absorption circulation pump is to pump out the mixed acid solution in the absorption tower, pressurize it and transport it to the cooler for cooling;

[0050] Among them, dilution water / dilute acid is added to the latter section of the pipeline from the outlet of the cooler to the absorption tower, and the addition amount is precisely controlled by the flow meter and the regulating valve;

[0051] After the dilution water / dilute acid is added, it is mixed with the circulating acid and enters the absorption tower together to be mixed with anhydrous hydrogen fluoride;

[0052] A hydrofluoric acid dilution process includes the following steps. S1 Process preparation:

[0053] Equipment inspection and preparation: Conduct a comprehensive inspection of the hydrofluoric acid dilution equipment composed of an absorption tower, an absorption circulation pump, a cooler, a distributor, a liquid level gauge, a regulating valve, a flow meter, and a finished acid concentration meter to ensure that the inside of the absorption tower is clean without impurity residues, the packing is complete and evenly distributed; check the sealing performance and impeller condition of the absorption circulation pump to ensure its normal operation; confirm that there is no leakage in the cooler pipeline and the heat exchange effect is good. At the same time, calibrate all measuring instruments such as the liquid level gauge, flow meter, and finished acid concentration meter to make their measurement accuracy meet the process requirements;

[0054] Raw material preparation: Prepare high-purity anhydrous hydrogen fluoride and dilution water / dilute acid that meet the process requirements. Detect the purity of anhydrous hydrogen fluoride to ensure that its impurity content is within the allowable range to avoid impurities affecting the quality of the diluted hydrofluoric acid. Calculate the required amounts of anhydrous hydrogen fluoride and dilution water / dilute acid according to the target dilution concentration;

[0055] S2 Initial cycle establishment:

[0056] Add dilution water / dilute acid: Add an appropriate amount of dilution water / dilute acid to the absorption tower, and start the absorption circulation pump to form a cycle among the absorption tower, the absorption circulation pump, and the cooler. During the cycle, check whether there is any leakage at each connection part to ensure good system sealing;

[0057] Start the cooling system: Start the cooling medium circulation of the cooler and set the cooling temperature. The setting of the cooling temperature only needs to consider removing the reaction heat;

[0058] S3 Hydrogen fluoride introduction and preliminary dilution:

[0059] Slowly introduce anhydrous hydrogen fluoride: After the internal circulation of the absorption tower is stably established and the cooling system is operating normally, slowly introduce anhydrous hydrogen fluoride. The anhydrous hydrogen fluoride is evenly distributed into the absorption tower through the distributor and is preliminarily mixed with the circulating acid at the lower distributor. Control the introduction speed of anhydrous hydrogen fluoride to avoid overly violent reactions caused by too fast introduction, which may lead to temperature and pressure fluctuations;

[0060] Real-time monitoring and regulation: During the introduction of anhydrous hydrogen fluoride, use the finished acid concentration meter to monitor the concentration change of the acid liquid in the absorption tower in real time, and at the same time monitor the liquid temperature in the tower through a thermometer. According to the concentration and temperature changes, finely adjust the introduction speed of anhydrous hydrogen fluoride and the cooling capacity of the cooler to maintain the stable progress of the reaction in the absorption tower;

[0061] S4 Secondary mixing and dilution enhancement:

[0062] Packing section mixing: The acid solution after preliminary mixing enters the packing section of the absorption tower for secondary mixing and dilution. The presence of the packing increases the gas-liquid contact area, strengthens the mixing effect of anhydrous hydrogen fluoride and dilution water / dilute acid. In the packing section, anhydrous hydrogen fluoride further dissolves and fully reacts with the dilution water / dilute acid, making the acid solution concentration more uniform;

[0063] Absorption tail gas treatment: The absorption tail gas is discharged from the lower part of the absorption tower and can be further processed according to actual conditions, such as recovering the unreacted hydrogen fluoride through a tail gas absorption device to reduce raw material waste and environmental pollution;

[0064] S5 Finished acid concentration regulation and discharge:

[0065] Concentration control: When it is detected that the concentration of the finished acid is close to the set value, the flow rate of the dilution water / acid is precisely adjusted through a flow meter and a regulating valve so that it enters the absorption tower at a set flow rate after mixing with the circulating acid. At the same time, the HF flow rate is automatically controlled by an outlet concentration meter and an HF pipeline regulating valve to ensure that the concentration of the finished acid in the absorption tower is stable at the set value;

[0066] Liquid level control and discharge: With the continuous addition of dilution water and HF, the liquid level in the absorption tower gradually rises. When the liquid level reaches the set value, under the action of a liquid level meter and a regulating valve, the finished acid automatically discharges from the absorption tower to maintain a constant liquid level in the absorption tower. The discharged finished acid enters the subsequent storage or use link;

[0067] S6 System maintenance and optimization:

[0068] Regular detection and maintenance: During the process operation, the device is regularly detected and maintained. Check the wear condition of the packing in the absorption tower and replace it in time if necessary; maintain the absorption circulation pump, such as replacing lubricating oil and checking mechanical seals; regularly calibrate the measuring instruments to ensure their measurement accuracy;

[0069] Data recording and analysis: Record various data during the process operation, such as temperature, pressure, flow rate, concentration. Through the analysis of these data, promptly discover abnormal situations in the process operation and optimize and adjust the process parameters to improve the stability of the hydrofluoric acid dilution process and product quality.

[0070] Furthermore, the scheme has high operation stability: The hydrofluoric acid dilution device and its dilution process of the present invention enable anhydrous hydrogen fluoride and dilution water / dilute acid to be mixed inside the absorption tower. After being distributed by the distributor, anhydrous hydrogen fluoride is mixed with the circulating acid at the lower distributor. This mixing method ensures that the slight gasification of anhydrous hydrogen fluoride will not cause fluctuations in the pipeline flow rate because the mixing occurs inside the tower, and the gasified anhydrous hydrogen fluoride will not affect the flow rate in the conveying pipeline, thus ensuring the stable operation of the device and effectively avoiding the problem of unstable product quality caused by flow rate fluctuations;

[0071] Furthermore, the concentration measurement of this solution is accurate and convenient for automatic control: The finished acid enters the bottom of the absorption tower through the packing section. The packing section can effectively separate the gas in the finished acid. The separation of the gas enables the accurate measurement of the concentration of the finished acid. Based on the accurate concentration measurement, combined with equipment such as flow meters, regulating valves, and finished acid concentration meters, the automatic control of the system can be achieved, precisely adjusting the flow rates of dilution water / acid and anhydrous hydrogen fluoride to ensure that the concentration of the finished acid is stable at the set value;

[0072] Furthermore, this solution is convenient for commissioning and coupling with subsequent processes: The initial commissioning of the system can be carried out in the device. Even if unqualified products appear during the commissioning process, they will not enter the subsequent processes, avoiding the impact of unqualified products on subsequent production links. At the same time, this device and process are convenient for coupling with subsequent processes, can better adapt to the entire production process, and improve the coherence and efficiency of production;

[0073] Furthermore, this solution has strong process sustainability: By setting up system maintenance and optimization links, regularly detecting and maintaining the device, including checking the wear of the packing in the absorption tower, maintaining the absorption circulation pump, calibrating measuring instruments, etc., ensuring the long-term stable operation of the device. The recording and analysis of process operation data help to promptly detect abnormalities and optimize process parameters, improving the stability of the hydrofluoric acid dilution process and product quality, and enhancing the sustainability and adaptability of the process.

[0074] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those of ordinary skill in the art in the described technical field, various changes can be made without departing from the purpose of the present invention.

Claims

1. A hydrofluoric acid dilution device, comprising an absorption tower, an absorption circulation pump, a cooler, a distributor, a liquid level gauge, a regulating valve, a flowmeter, and a finished acid concentration meter. Anhydrous hydrogen fluoride is connected to the top of the absorption tower through a pipeline and evenly distributed into the tower through the distributor (distributor 1). It is characterized in that: There are two levels of distributors, an upper distributor and a lower distributor, inside the absorption tower. The upper distributor receives anhydrous hydrogen fluoride, and the lower distributor is used for the mixing of anhydrous hydrogen fluoride and the circulating acid; The absorption tower is filled with packing, and the mixed acid solution flows through the packing for secondary mixing and dilution; The bottom of the absorption tower is connected to the inlet of the absorption circulation pump through a pipeline to transport the mixed acid solution in the tower out; A liquid level gauge is installed on the side of the absorption tower to monitor the liquid level in the tower, and a regulating valve is also provided on the absorption tower.

2. The hydrofluoric acid dilution device and dilution process according to claim 1, characterized in that: The inlet of the absorption circulation pump is connected to the bottom of the absorption tower, and the outlet is connected to the inlet of the cooler through a pipeline.

3. The hydrofluoric acid dilution device and its dilution process according to claim 1, characterized in that: The function of the absorption circulation pump is to pump out the mixed acid solution in the absorption tower and pressurize it for transportation to the cooler for cooling.

4. A hydrofluoric acid dilution device and its dilution process according to claim 1, characterized in that: The absorption tail gas is discharged from the lower part of the absorption tower.

5. The hydrofluoric acid dilution device and dilution process according to claim 1, characterized in that: Diluted water / diluted acid is added to the latter section of the pipeline from the outlet of the cooler to the absorption tower, and the addition amount is precisely controlled by a flow meter and a regulating valve.

6. A hydrofluoric acid dilution device and its dilution process according to claim 1, characterized in that: After the diluted water / diluted acid is added, it is mixed with the circulating acid and enters the absorption tower together to be mixed with anhydrous hydrogen fluoride.

7. A hydrofluoric acid dilution process, characterized in that: It includes the following steps. S1 Process preparation: Equipment inspection and preparation: Conduct a comprehensive inspection on the hydrofluoric acid dilution device composed of an absorption tower, an absorption circulation pump, a cooler, a distributor, a liquid level gauge, a regulating valve, a flow meter, and a finished acid concentration meter to ensure that the inside of the absorption tower is clean, without residual impurities, the packing is complete and evenly distributed; Check the sealing performance and impeller condition of the absorption circulation pump to ensure its normal operation; Confirm that there is no leakage in the cooler pipeline and the heat exchange effect is good. At the same time, calibrate all measuring instruments, such as the liquid level gauge, the flow meter, and the finished acid concentration meter, so that their measurement accuracy meets the process requirements; Raw material preparation: Prepare high-purity anhydrous hydrogen fluoride and diluted water / diluted acid that meet the process requirements. Detect the purity of anhydrous hydrogen fluoride to ensure that its impurity content is within the allowable range to avoid impurities affecting the quality of the diluted hydrofluoric acid. Calculate the required amounts of anhydrous hydrogen fluoride and diluted water / diluted acid according to the target dilution concentration; S2 Initial cycle establishment: Add diluted water / diluted acid: Add an appropriate amount of diluted water / diluted acid to the absorption tower, start the absorption circulation pump, and make the diluted water / diluted acid form a cycle among the absorption tower, the absorption circulation pump, and the cooler. During the circulation process, check whether there is any leakage at each connection part to ensure good system sealing; Start the cooling system: Start the cooling medium circulation of the cooler and set the cooling temperature. The setting of the cooling temperature only needs to consider removing the reaction heat; S3 Hydrogen fluoride introduction and preliminary dilution: Slowly introduce anhydrous hydrogen fluoride: After the internal circulation of the absorption tower is stably established and the cooling system is operating normally, slowly introduce anhydrous hydrogen fluoride. The anhydrous hydrogen fluoride is evenly distributed into the absorption tower through the distributor and is preliminarily mixed with the circulating acid at the lower distributor. Control the introduction speed of anhydrous hydrogen fluoride to avoid overly violent reactions caused by too fast introduction, which may lead to temperature and pressure fluctuations; Real-time monitoring and regulation: During the introduction of anhydrous hydrogen fluoride, use the finished acid concentration meter to monitor the concentration change of the acid solution in the absorption tower in real time, and at the same time monitor the liquid temperature in the tower through a thermometer. According to the concentration and temperature changes, finely adjust the introduction speed of anhydrous hydrogen fluoride and the cooling capacity of the cooler to maintain the stable progress of the reaction in the absorption tower; S4 Secondary mixing and dilution enhancement: Packing section mixing: The acid solution after preliminary mixing enters the packing section of the absorption tower for secondary mixing and dilution. The presence of the packing increases the gas-liquid contact area, strengthens the mixing effect of anhydrous hydrogen fluoride and dilution water / dilute acid. In the packing section, anhydrous hydrogen fluoride further dissolves and fully reacts with the dilution water / dilute acid, making the acid solution concentration more uniform; Treatment of absorption tail gas: The absorption tail gas is discharged from the lower part of the absorption tower and can be further processed according to actual conditions. For example, the unreacted hydrogen fluoride in it can be recovered through a tail gas absorption device to reduce raw material waste and environmental pollution; S5 Regulation and discharge of finished acid concentration: Concentration control: When it is detected that the concentration of the finished acid is close to the set value, the flow rate of dilution water / acid is precisely adjusted through a flow meter and a regulating valve so that it enters the absorption tower at a set flow rate after mixing with the circulating acid. At the same time, the flow rate of HF is automatically controlled by an outlet concentration meter and an HF pipeline regulating valve to ensure that the concentration of the finished acid in the absorption tower is stable at the set value; Liquid level control and discharge: With the continuous addition of dilution water and HF, the liquid level in the absorption tower gradually rises. When the liquid level reaches the set value, under the action of a liquid level meter and a regulating valve, the finished acid automatically discharges from the absorption tower to maintain a constant liquid level in the absorption tower. The discharged finished acid enters the subsequent storage or use link; S6 System maintenance and optimization: Regular inspection and maintenance: During the process operation, the device is regularly inspected and maintained to check the wear condition of the packing in the absorption tower and replace it in time if necessary; Maintain the absorption circulation pump, such as changing the lubricating oil and checking the mechanical seal; regularly calibrate the measuring instruments to ensure their measurement accuracy; Data recording and analysis: Record various data during the process operation, such as temperature, pressure, flow rate, concentration. Through the analysis of these data, promptly detect abnormal situations in the process operation and optimize and adjust the process parameters to improve the stability of the hydrofluoric acid dilution process and product quality.

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