重庆市雨水利用的混凝试验研究

Coagulation for Reuse of Rainwater in Chongqing

通过对重庆市某校园内雨水径流水质的监测分析,掌握不同下垫面类型、降雨强度下的雨水径流水质特性及变化规律,为重庆市建筑与小区雨水资源化利用提供数据支撑和设计依据。在此基础上,以聚合氯化铝为混凝剂,采用屋面雨水和地面雨水不同配比配置不同浊度梯度的试验用水,通过烧杯混凝试验研究,确定了投加量对不同进水水质下的不同污染物指标去除效果的影响,各指标去除率总体表现为随投加量的增加先增大后减小。将COD作为雨水资源化利用的主要控制指标,当以聚合氯化铝为混凝剂时,进水COD为0～30 mg/L的最佳投加量为10 mg/L;COD为30～60 mg/L的最佳投加量为10～20 mg/L;COD为60～90 mg/L的最佳投加量为20～40 mg/L。

Based on the rainwater quality monitored in a university campus in Chongqing, the rules of polluted degree and the variation regulation of runoff quality in different underlying surface and rainfall intensity were analyzed as data support for the rainwater reuse in building and district in Chongqing. By jar test of raw water with different rainwater quality, combined in different proportion with rainwater from roof and ground, we determinated the influence of the additive amount on different removing pollutant indexes under different water quality, and the overall performance for the removal rate of each index first increases and then decreases with the increase of the dosing quantity. And the effect and the best dosages of PAC on the removal of water quality index were obtained, which are 10 mg/L with influent COD 0 -30 mg/L, 10 -20 mg/L with 30 -60 mg/L and 20-40 mg/L with 60 - 90 mg/L.