实验室废液降危减量化处理工艺与工程案例

Treatment process and engineering cases for the risk and quantity reduction of laboratory liquid waste

实验室废液降危减量化处理是控制废液环境风险、缓解危废处置能力不足、降低处置成本的重要途径。系统解析了4种典型实验室废液水质特征,提出"分类预处理+二级处理+末端吸附"的废液降危减量化处理思路。现场处理结果表明:分类混合废液中汞、铬、铅等一类污染物浓度较工业废液低,经处理后一类污染物均可达标,最终可纳入社区污水处理与再生利用系统深度净化回用或达标纳管排放;采用该工艺可将实验室废液总量减量40%~90%,第三方委托处置成本可降低85%。该工艺与应用案例可为科技园区、研究所或大学的实验室废液处理处置提供参考。

The risk and quantity reduction treatment of laboratory liquid waste is of crucial importance to control the lab environmental risks, alleviate the capacity shortage for hazardous waste disposal and decrease the disposal cost. This study carefully investigated the water quality characteristics of the laboratory liquid waste,and put forward the feasible treatment process to reduce the liquid waste amount and to minimize the environmental risks as much as possible. To achieve this goal, the laboratory liquid wastes are proposed to be separately pretreated according to their characters, then these classified liquid wastes are treated by secondary unit processes such as metals decomplexation and chemical precipitation. Finally, adsorption is used as the tertiary treatment process to achieve the Integrated Wastewater Discharge Standard for the effluents to urban drainage. Results of field investigation indicated that the concentrations of class-I pollutants such as Hg, Cr, and Pb were lower than those in industrial hazardous liquid waste, which can be treated by the proposed treatment process to meet the corresponding standards. The final effluents may be either discharged directly into the municipal drainage systems or be discharged into the community-level wastewater treatment station for further purification and reclamation. This process may reduce the amount of laboratory liquid wastes by 40%~90% and the cost by 85% as compared to be disposed by the third-party companies for hazardous wastes disposal. The process and its application cases provide reference for the disposal of the laboratory liquid wastes in research institutes, universities, and the Science Parks and so on.