秦岭输水隧洞施工期废水水质评价及工艺研究

The evaluation on Wastewater Quality and Investigation on Wastewater Treatment During Qin Ling Water-conveyance Tunnel Construction Period

依据前期对施工废水水质的连续监测和分析检测结果,针对秦岭输水隧洞施工期废水水量较大、高SS等特点,基于水质矩阵分析原理,以废水处理后安全外排为约束,对各污染物进行权重分析,得出污染物对环境影响由高到低依次是SS、COD、Fe、NH3-N、TN、石油类。结果表明SS是制约隧洞施工废水安全外排的控制因子。根据废水污染物的构成,提出了以"混凝+沉淀+锰砂过滤+吸附"为核心的处理工艺,并用施工现场采集的废水以及人工模拟废水进行了实验室静态实验。结果表明,该处理工艺对悬浮物去除率达90%以上,对COD去除率约85%,对氨氮去除率约60%。处理后水质均能满足《地表水环境质量标准》(GB 3838-2002)中Ⅱ类水体指标。

According to the continuous monitoring and investigating results of previous constructional wastewater quality,focused on the large quantity of wastewater and high SS content during Qinling water-conveyance tunnel construction period,based on the water matrix analyzing principal,restricted by the treated wastewater safely emission standard to conduct the weighting analysis on each contaminant,it can be found that the order of each contaminant ranking from high environmental impact to low is SS,COD,Fe,NH3-N,TN,oil type.The result shows that SS is the controlling factor which restricts the safely emission of wastewater during the tunnel construction.According to the composition of wastewater contaminants,the treatment combined with coagulation,precipitation,manganese filtration and adsorption was proposed,and the static experiments of wastewater collected from construction site and manual simulated wastewater were conducted.And the result indicates that the removal rate of SS can reach 90%,the removal rate of COD is 85% and the removal rate for ammonia nitrogen is about 60%.And the treated water quality can meet the demand of Ⅱ water index in accordance with 'Environmental Quality Standards for Surface Water'(GB3838-2002).