REUSE METHOD OF WASTE SULFURIC ACID AS ACID WASHING LIQUID AND INORGANIC COAGULANT OF FERROUS SULFATE

摘要

PURPOSE: A reuse method of waste sulfuric acid as an acid washing liquid and an inorganic coagulant of ferrous sulfate is provided, which can reuse the waste sulfuric acid, eliminate high treatment cost required to treat the acid, and solve landfill problems associated with water treatment plants. CONSTITUTION: The method comprises as follows: (i) dissolve by feeding iron component to waste solution of sulfuric acid to get 220 gram per liter of FeSO4; (ii) filter the residue solid and separate free sulfuric acid contained in waste sulfuric acid solution and iron ion component by diffusion dialyzing with keeping the flow velocity of recovered acid region higher than that of metal waste solution region and by controlling the flow velocity range of both sides to 600-1200 ml per square meter hour; and (iii) measure the concentration of the recovered acid and iron ion-containing metal waste solution which are obtained by diffusion dialysis, before keeping the concentration of recovered acid at the proper acid washing concentration range of 150-250 gram per liter and the concentration of iron ion-containing metal waste solution at 200-400 gram per liter of ferrous sulfate contained in metal waste solution, followed by using them as acid washing solution and an inorganic coagulant respectively.