Method for recovering hydrochloric acid from germanium concentrate distillation waste liquid

Abstract

The invention discloses a method for recovering hydrochloric acid from germanium concentrate distillation waste liquid. The method comprises the following steps of primarily separating hydrochloric acid and salt solution in the germanium concentrate distillation waste liquid through evaporation and concentration; performing cyclone concentration on the concentrated salt solution; then, performingcentrifuge dripping to obtain crystal products of zinc chloride, ferric chloride, lead chloride and the like; feeding the crystal products into a zinc melting flow process smoking furnace to recover lead and zinc; after condensing diluted acid subjected to evaporation concentration is collected through a collecting tank, conveying the condensing diluted acid into a desorption tower through a hydrochloric acid conveying pump to be mixed with a certain concentration of calcium chloride solution; performing continuous contact reverse flow mass transfer on the high-temperature chlorine hydride gasheated through a reboiler, water vapor and calcium chloride so that the constant boiling point of dilute hydrochloric acid can be broken and the chlorine hydride content of the rise gas is continuously increased; after the cooling by cooling water, returning hydrochloric acid with the concentration being 30 percent or higher subjected to two-stage falling film absorption into the germanium concentrate for distillation and use; conveying the desorption tower diluted calcium chloride solution into a concentration tower to be subjected to evaporation concentration; then, conveying the solution to the desorption tower for cyclic use. The method for recovering hydrochloric acid from the germanium concentrate distillation waste liquid provided by the invention has the advantages that cleannessand high efficiency are realized; the outsourcing hydrochloric acid consumption in the distillation process is reduced; the production cost is reduced.

Description

technical field [0001] The invention relates to the technical field of germanium smelting and purification, in particular to an environmentally friendly and efficient method for recovering hydrochloric acid from germanium concentrate distillation waste liquid. Background technique [0002] At present, in germanium production, germanium tetrachloride is produced through the mixed distillation of germanium concentrate and concentrated hydrochloric acid to extract germanium. After the distillation of germanium concentrate is completed, a large amount of distillation waste liquid will be produced. This part of waste liquid is mainly composed of chloride salt and reaction Dilute hydrochloric acid with reduced concentration after mixing exists, which is highly corrosive and volatile, and has a great impact on the health of surrounding personnel and the environment. At present, most of them are treated by direct neutralization. The neutralization process is complicated, and it is n...

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Problems solved by technology

[0002] At present, in germanium production, germanium tetrachloride is produced through the mixed distillation of germanium concentrate and concentrated hydrochloric acid to extract germanium. After the distillation of germanium concentrate is completed, a large amount of distillation waste liquid will be produced. This part of waste liquid is mainly composed of chloride salt and reaction Dilute hydrochloric acid with reduced concentration after mixing exists, which is highly corrosive and volatile, and has a great impact on the health of surrounding personnel and the environment

At present, most of them are treated by direct neutralization. The neutralization process is complicated, and it is necessary to adjust the pH and control the adding speed of the neutralizer. Neutralizing solution generation

Derived new pollution sources of the three wastes, which have an impact on the environment, and at the same time failed to recycle the useful components, resulting in a waste of resources

[0003] Prior art CN100340472C proposes distillation, drying, absorption and recovery of hydrochloric acid in germanium concentrate distillation waste liquid, because germanium concentrate distillation waste liquid is azeotropic acid, desiccant CaCl 2 The consumption is large, and the solution still needs to be treated by neutralization after distillation, and there are still some neutralization residues

[0004] In addition, researchers have done a lot of research on the recovery of dilute hydrochloric acid, and have proposed many methods for the concentration and recovery of dilute hydrochloric acid, such as distillation with salt, batch distillation, etc., but the treatment objects of the above methods are all steel washing wastewater and galvanizing wastewater. There are certain limitations in the treatment of germanium concentrate distillation waste liquid. For example, dilute hydrochloric acid solution is relatively simple, and the acidity of hydrochloric acid after treatment is low, which cannot meet the requirements for the use of germanium concentrate distillation. The process is complicated and has no practical application value, etc.

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