Method and device for preparing hydrogen fluoride through low-grade superfine fluorite powder

Abstract

The invention discloses a method for preparing hydrogen fluoride through low-grade superfine fluorite powder. The method comprises following steps of a. adding 98 acid and 105 acid into a niacin reactor according to a proportion and mixing; b. putting 500-300 meshes of fluorite powder containing 90-93% of calcium fluoride and sulfuric acid treated through acid mixing in the niacin reactor into a pre-reactor according to a conventional proportion for pre-reaction; c. putting the fluorite powder treated in above steps, sulfuric acid and hydrogen fluoride into a reaction converter, and under the action of a spiral crushing device in the reaction converter, constantly exchanging heat with the 300-400 DEG C inner wall of the converter so as to finish the reaction, wherein when the conversion rate of calcium fluoride reaches 97%, fluorgypsum is sent to a gypsum groove, and the gas hydrogen fluoride escapes from the burner of the reaction converter; d. sending the gas hydrogen fluoride escaping from the burner of the reaction converter in the last step into a dust clearing device to be cleared and separated. The invention also discloses a device for the method.

Description

[0001] technical field [0002] The invention relates to a method for producing hydrogen fluoride, in particular to a method for preparing hydrogen fluoride by using low-grade ultrafine fluorite powder, and also relates to a device for realizing the method. Background technique [0003] Hydrogen fluoride is the basic raw material of the fluorine chemical industry and the key raw material of various fluorine-containing products. At present, the rotary kiln process is commonly used to produce hydrogen fluoride from fluorite. The preparation of hydrogen fluoride from conventional fluorite powder includes the following steps: add fluorite with a calcium fluoride content of 97%, a particle size of 100 mesh, and sulfuric acid from the nicotinic acid reactor to the pre-reactor at a mass ratio of 1:1.2-1.5, and the nicotinic acid reactor The mass ratio of 98 acid and 105 acid is 1.4-1.7:1, and the steam temperature of the pre-reactor is 150-160°C; after the preliminary reaction bet...

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Problems solved by technology

However, there are still many technical difficulties in the current converter production process using this low-grade ultrafine fluorite powder to prepare hydrogen fluoride: 1. Since the low-grade fluorite contains a large amount of oxides, more water will be generated during the reaction, which will Exacerbating the corrosion of the system, the processing conditions of conventional fluorite powder are not suitable for the preparation of hydrogen fluoride with low-grade ultra-fine fluorite powder; 2. Due to the reduction of the particle size of the above-mentioned low-grade ultra-fine fluorite powder, a large number of crusts will result in the reaction furnace, reducing heat transfer Efficiency; 3. Since the particle size of the above-mentioned low-grade ultra-fine fluorite powder is half of that of conventional fluorite powder, a large amount of fluorite powder will enter the scrubber along with the hydrogen fluoride gas, which will cause blockage of the gas duct of the reaction furnace head

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