El medio ambiente en la minería

EL MEDIO AMBIENTE'EN LA MINERIA 140 The S02 gas contained in the fugitive gas is desulfurized and flXed as MgS03 or MgS04- Then it is sent to an effiuent ~reatment plant afier oxidation to MgS04- Figure 12 shows the flow sheet for the fugitive gas cleaning system. FUOXTXUE orAS (Collec~ed ~hroush eech local hood) ¡ 0.2 AbsDm:lng Wet E.S.P. I • '+' Figure 12. Fugitive gas colleciing system. Aciel Plant Blowdown Process Weak acid in the acid plant's gaswashing process is ejected from the circulation system after the lead is removed as lead sulphate. 118 sulphuric acid concentra– lion is about 150 gil. Thís weak acid dissolves many of the impurities contained in the offgas such as halogen, arseniC, zinc and copper. A typical assay is shown in TabIe7. Sulphuric acid is neutralized with lime stone milk, and gypsum is produced as one of the produc18 at Toyo Smelter. Then, the heavy metaL~ dissolved in the weak acid, such as copper, arsenic and zinc, are sulphurized with sodium