Method for extracting germanium from lignite by pyrogenic process

Abstract

The invention provides a method for extracting germanium from lignite through a pyrogenic process. The method is characterized in that germanium-containing lignite volatilizes germanium in a pyrogenic-process smelting procedure of a vertical kiln; a control condition of volatilizing germanium is that the temperature is between 1,150 and 1,250 DEG C; in a suitable reducing atmosphere, the germanium existing as germanium dioxide generates germanium monoxide after reduction reaction through carbon particles and carbon monoxide; a suitable oxidizing atmosphere ensures that the germanium monoxide follows dust particles volatilized simultaneously to meet excessive oxygen in a flue gas tube and then is oxidized to be the germanium dioxide; the temperature of the germanium dioxide is lowered through a cooler; the generated germanium dioxide is changed into a solid state and is attached to the surfaces of the dust particles; the germanium-enriched dust particles pass an electrostatic dust catcher and then are attached to the electrostatic dust catcher; and germanium-enriched electrostatic dust is collected so as to obtain germanium concentrate. The method is advanced in technology, economical, practical and low in cost for extracting germanium. Compared with a chain-boiler germanium extracting process and other germanium extracting methods, the method has the advantages that the method is high in germanium volatilizing efficiency, the direct recovery rate of the electrostatic dust, the germanium-containing grade of the electrostatic dust and the post wet treatment yield of the output electrostatic dust, and is convenient for subsequent processing, and the like.

Description

technical field [0001] The invention belongs to the technical field of extraction of nonferrous and rare metals, in particular to a method for extracting germanium from lignite by fire method. Background technique [0002] Lignite, one of the raw materials for extracting germanium by fire method, generally has a germanium content of 30ppm to 200ppm. When using traditional blast furnace smelting, chain furnace with transmission grate, and manual furnace with fixed grate to extract germanium, when The calorific value of germanium-containing lignite is too low. If it is in the range of 8360-14630kj / kg, if such equipment is used for smelting and extracting germanium, the temperature in the furnace is difficult to exceed 1100 °C, and the volatilization rate of germanium is low. The low grade of soot and the low efficiency of bag dust removal have resulted in a low recovery rate of germanium, and the produced germanium soot has not been subjected to the process of decarburization ...

AI Technical Summary

Problems solved by technology

[0002] Lignite, one of the raw materials for extracting germanium by fire method, generally has a germanium content of 30ppm to 200ppm. When using traditional blast furnace smelting, chain furnace with transmission grate, and manual furnace with fixed grate to extract germanium, when The calorific value of germanium-containing lignite is too low. If it is in the range of 8360-14630kj / kg, if such equipment is used for smelting and extracting germanium, the temperature in the furnace is difficult to exceed 1100 °C, and the volatilization rate of germanium is low. The low grade of soot and the low efficiency of bag dust removal have resulted in a low recovery rate of germanium, and the produced germanium soot has not been subjected to the process of decarburization and de-coal tar at a higher temperature, and the acid solubility of germanium is poor. Problems such as low recovery rate of post-wet treatment

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