| 摘要 |
FIELD: waste water purification. SUBSTANCE: invention relates to methods for isolation of arsenic from acidic aqueous solutions and can be applied in chemical industry and nonferrous metallurgy for removing arsenic from waste water, in particular, in sulfuric acid production, etc. Acidic waste water is treated with disintegrated iron scrap. Evolving hydrogen arsenide is subjected to thermal dissociation to form elementary arsenic and hydrogen. Finally, pretreated waste water is treated with sodium ferrate to completely remove arsenic. Installation contains reactor 6 with filtering iron scrap charge 7, horizontal settler 1, pipelines for supplying untreated waste water (2,3), withdrawing clarified water (4), and removing sludge (5). Settler 1 is separated into compartments 10 by removable vertical filter members 11 constituting perforated steel containers filled with crushed rock-iron scrap mix. Each compartment is provided with slurry-admission valve 12 of sludge pump 13 and is connected with reagent dispensers 14. Reactor 6 is joined with thermal hydrogen arsenide dissociator 9 through gas-release pipeline 8. EFFECT: improved design of installation and process flowsheet. |
