(中南大学 冶金与环境学院，长沙 410083)
摘 要: 多金属矿选矿废水具有悬浮物浓度和化学需氧量(COD)高、重金属浓度低但种类多等特点，难以稳定达标排放。采用含铝无机高分子混凝剂和有机助凝剂两步混凝沉淀处理钨铋钼矿选矿废水，24 h 现场动态取样研究结果表明，混凝沉淀法可高效处理钨多金属矿选矿废水。在废水中先后投加0.75%(体积分数)质量浓度为27 g/L(以铝计)的含铝无机高分子混凝剂和0.5%(体积分数)质量浓度为1 g/L 的有机助凝剂，混凝沉淀4 min 后，选矿废水浊度去除率达96.5%以上，COD 去除率达70%左右；废水中As 和Pb 去除率分别达90%和97.6%以上，Be 和Cd去除率几乎达100%。处理后废水浊度小于50 NTU、COD 平均含量降至58 mg/L，废水中As 和Pb 浓度分别降至0.5 mg/L 和80 μg/L 以下，未检出Be 和Cd，出水水质满足《污水综合排放标准》(GB 8978-1996)一级标准。
关键字: 钨铋钼矿；多金属矿选矿废水；混凝沉淀法；现场试验
（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
