Sampling device and sampling method for anhydrous hydrogen fluoride

Abstract

The invention relates to a sampling device and a sampling method for anhydrous hydrogen fluoride. An original ice dissolving method is changed into an external ice water cooling method, so that freezing treatment is not required to be performed on pure water in a sampling bottle before sampling, the sampling cost is greatly reduced, and the sampling efficiency is greatly improved; in addition, the fact that a sampling person holds the sampling bottle with one hand to adjust the position of the opening of a sampling pipe in the ice dissolving method is avoided, therefore, all that is required for the sampling person is to stand and performs operations with one hand, and the sampling method is safe and convenient; meanwhile, a reducer is installed at an outlet of a ball valve, an original DN20 pipe is changed into a 1 / 4-inch pipe (a PFA pipe or an F46 pipe), a 1 / 4-inch PFA ball valve is used for replacing a steel bottle valve, and a 1 / 4-inch F46 pipe provided with a bottle cap is connected to the back end of the a 1 / 4-inch PFA ball valve, so that the washing amount is less, the washing is fuller, external impurities such as dust and the like can be effectively prevented from entering the pipe, and the sampling safety, accuracy and reality are guaranteed.

Description

technical field [0001] The invention belongs to the technical field of analytical chemistry, and in particular relates to an anhydrous hydrogen fluoride sampling device and a sampling method. Background technique [0002] Industrial anhydrous hydrogen fluoride is a chemical product with a wide range of uses. The appearance is more than 99% hydrofluoric acid of colorless fuming liquid, which is easy to gasify under reduced pressure or high temperature. It is mainly used to prepare fluorine salts, fluorohalogenated hydrocarbons, fluorine refrigerants, corrode glass, impregnate wood, and electrolyze elemental fluorine, etc. [0003] Anhydrous hydrogen fluoride has been widely used in atomic energy, chemical industry, petroleum and other industries. It is a strong oxidizing agent and the basic raw material for preparing elemental fluorine, various fluorine refrigerants, inorganic fluorides, and various organic fluorides. It can be formulated into various Applications include hy...

AI Technical Summary

Problems solved by technology

[0010] The above-mentioned sampling device and sampling method have the following potential safety hazards and defects:

[0011] 1. The method of melting ice is used for sampling. It takes 10-12 hours for the formation of frozen ice 2 to take a long time. Due to the large amount of sampling in industrial production, more sampling bottles 1 need to be prepared, which will inevitably affect the cost and efficiency of sampling analysis. ;

[0012] 2. The pipe diameter of the sampling pipeline is relatively large. When cleaning the sampling pipeline, if the valve is opened large, the reaction of anhydrous hydrogen fluoride flowing into the waste discharge bucket 8 will be very violent and difficult to control. If the valve is opened small, the flow rate is small and the It is impossible to fill the inner wall of the sampling pipeline with anhydrous hydrogen fluoride, resulting in inadequate cleaning and affecting the authenticity of subsequent sampling;

[0013] 3. When sampling, you need to open the valve with one hand and hold the sampling bottle 1 with the other hand. Once there is an accident, it is difficult to respond and deal with it in time; also due to the large diameter of the sampling pipeline, it is difficult to control, especially the cylinder valve 5 that has been used for a long time. Its outlet end is exposed to the air for a long time (such as Figure 4 As shown, the 1 / 2-inch F46 pipe 7 is connected to the outlet end of the cylinder valve 5), the valve core inside the valve is easily corroded, and the valve is difficult to open, which also brings potential safety hazards;

[0014] 4. Since anhydrous hydrogen fluoride easily volatilizes into smog at room temperature and normal temperature, and becomes hydrofluoric acid due to intense heat release when dissolved in water, so when the cylinder valve 5 is installed, it is about 30cm away from the ground, and the sampler must squat to take the sample , once there is an accidental sampler, it is extremely inconvenient to do relevant safety disposal;

[0015] 5. After sampling, the outlet end of cylinder valve 5 is directly exposed to the air. Since the air contains moisture, anhydrous hydrogen fluoride remains at the outlet end of cylinder valve 5. Therefore, iron products such as cylinder valve 5 are easily damaged. Water hydrofluoric acid corrosion, the valve core inside the valve is corroded, which makes it difficult to open the valve and control the flow;

[0016] 6. After sampling, the nozzle of 1 / 2-inch F46 tube 7 is directly exposed to the air, and a large amount of dust will be adsorbed to 1 / 2-inch F46 tube 7 and The inner wall of the copper pipe 6 increases the difficulty of cleaning, and the amount of anhydrous hydrogen fluoride required for cleaning increases, especially in seasons and areas where the air is relatively dry, the amount of dust contained in the dry air is large, and most of the factory area is Calcium fluoride, calcium sulfate and other dust, so the authenticity of sampling is greatly affected, and abnormalities often occur during sulfate analysis, and the corrosion of valves and pipelines also increases the ferrous ions in the sample, resulting in An exception occurred when analyzing sulfur dioxide and potassium permanganate

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