A resourceful treatment method and device for arsenic sulfide waste residue

Abstract

The invention discloses a recycling treatment method for arsenic sulfide waste residue. It obtains thioarsenite or thioarsenate solution by alkaline leaching, removes the residue by filtering through a filter to obtain an alkaline leaching solution, and then performs oxidative desulfurization. Substitute arsenite or thioarsenate is oxidized to arsenite or arsenate ion, and then filtered through another filter to separate elemental sulfur to obtain arsenite or arsenate solution, which can be used The bipolar membrane device recovers acid and alkali, the alkaline solution is returned for alkaline leaching, the acid solution is used for crystallization to prepare As2O3 or As2O5, the bipolar membrane salt chamber residue enters electrodialysis or reverse osmosis concentration, and the concentrated solution is returned as the bipolar membrane device. Salt room intake, fresh water discharge or recovery; the invention solves the problems of high consumption of traditional arsenic sulfide waste residue treatment methods, substandard arsenic content in effluent water, low resource recovery rate, complicated process flow and secondary pollution, etc., and the arsenic content in effluent is stable It meets the standard, and the recovery rate of As and S resources is high, and it has the advantages of less consumption, low operating cost, and simple process flow.

Description

technical field

[0001] The invention belongs to the field of solid waste treatment, and in particular relates to a resource treatment method and device for arsenic sulfide waste residue. Background technique

[0002] Arsenic in arsenic sulfide waste residue is in the form of amorphous sulfide (such as As 2 S 2 or As 2 S 3 or As 2 S 5 and other forms), it is very easy to dissolve arsenic in an acidic or alkaline environment, which will pose a serious threat to natural water resources. At the same time, arsenic and its compounds are also a valuable resource widely used in pesticides, herbicides, insecticides, dyes and alloys. Traditional methods for treating arsenic sulfide slag mainly include: dry method and wet method.

[0003] The dry method refers to the treatment of arsenic sulfide slag by oxidation roasting, reduction roasting and vacuum roasting. 2 o 3 It is the most commonly used method to recover arsenic trioxide from arsenic sulfide slag in China. The dry p...

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