(中南大學 冶金與環(huán)境學院，長沙 410083)
摘 要: 多金屬礦選礦廢水具有懸浮物濃度和化學需氧量(COD)高、重金屬濃度低但種類多等特點，難以穩(wěn)定達標排放。采用含鋁無機高分子混凝劑和有機助凝劑兩步混凝沉淀處理鎢鉍鉬礦選礦廢水，24 h 現(xiàn)場動態(tài)取樣研究結(jié)果表明，混凝沉淀法可高效處理鎢多金屬礦選礦廢水。在廢水中先后投加0.75%(體積分數(shù))質(zhì)量濃度為27 g/L(以鋁計)的含鋁無機高分子混凝劑和0.5%(體積分數(shù))質(zhì)量濃度為1 g/L 的有機助凝劑，混凝沉淀4 min 后，選礦廢水濁度去除率達96.5%以上，COD 去除率達70%左右；廢水中As 和Pb 去除率分別達90%和97.6%以上，Be 和Cd去除率幾乎達100%。處理后廢水濁度小于50 NTU、COD 平均含量降至58 mg/L，廢水中As 和Pb 濃度分別降至0.5 mg/L 和80 μg/L 以下，未檢出Be 和Cd，出水水質(zhì)滿足《污水綜合排放標準》(GB 8978-1996)一級標準。
關(guān)鍵字: 鎢鉍鉬礦；多金屬礦選礦廢水；混凝沉淀法；現(xiàn)場試驗
（School of Metallurgy and Environment,Central South University,Changsha 410083,China）
Abstract:Dressing wastewater is characterized by several aspects,such as high suspended solids and chemical oxygen demand (COD) concentration,low metal concentrations,and hardly meets the discharge demand,and so on. In this work,the treatment of wastewater from W,Bi and Mo ore dressing process using inorganic polymer coagulant containing aluminum followed with organic flocculant was studied through 24-hour dynamic test on site. The results show that the wastewater from W containing multi-metal ore dressing process can be treated effectively by the coagulation combined with sedimentation. When 0.75% (volume percentage) inorganic containing aluminum polymer coagulant of 27 g/L (balance with aluminum) and 0.5% (volume percentage) organic flocculant of 1 g/L were added to the wastewater from W,Bi and Mo ore dressing process,the removal percentage of wastewater turbidity exceeds 96.5% after 4 min,that of COD is about 70%,and those of As and Pb in wastewater exceed 90% and 97.6%,while those of Be and Cd are both almost 100%,respectively. The residual concentrations of turbidity and COD in wastewater are only 50 NTU and 58 mg/L,while those of As and Pb are less than 0.5 mg/L and 80 μg/L and of Be and Cd are below the detection limit,respectively. After coagulation and sedimentation,the quality of wastewater from W,Bi and Mo ore dressing process can meet the grade I level of the National Integrated Wastewater Discharge Standard (GB 8978-1996).
Key words: W,Bi and Mo ore; multi-metal ore dressing wastewater; coagulation-sedimentation method; field test
