特征水质指标空间修正插值法预测混合供水带

针对多水源供水地区不同水厂之间存在混合供水带,水力水质条件不稳定,易出现铁释放超标、余氯偏低等水质问题,采用特征水质指标空间修正插值法预测该水质风险区域。特征水质指标是指不同水厂出厂水差异较大,且在管网中按一定规律分布、具有明显识别特征的水质指标,根据其空间分布情况可以判断各水厂单独及混合供水区域。考虑到管网分布与地理空间差异,在插值前引入修正系数对特征指标进行修正。以双水厂供水的H市为例预测混合供水带,结果表明:H市一般特征指标电导率和敏感特征指标总铁质量浓度的空间修正插值结果基本一致,且与水力模型模拟结果基本吻合;在所预测的混合供水带内设置在线监测点,观测到流速、流向的频繁改变,符合混合供水带水力特征,说明预测结果正确,方法可行。

Prediction of mixed water supply zone by spatial modified interpolation of characteristic water quality index

There are mixed water supply zones between different water plants in multi-source water supply areas, where the hydraulic water quality conditions are not stable, and water quality problems such as excessive iron release and low residual chlorine are easy to occur. The mixed water quality risk area can be predicted by using the spatial modified interpolation method of characteristic water quality index. Characteristic water quality index refers to the index with distinct identifying characteristics, which are distributed regularly in the water distribution system and have large differences in the finished water of different water plants. According to its spatial distribution, the separate water supply area and mixed water supply area of each water plant can be determined. However, there are great differences between the distribution of pipe network and the geographical space, so the correction coefficient should be introduced before interpolation to correct the characteristic index. In this study, the mixed water supply zone of H city was predicted. Results show that the spatial modified interpolation results of the characteristic water quality index conductivity and total iron concentration of H city were basically consistent, and accorded with the results of hydraulic model simulation. Online monitoring points were set in the predicted mixed water supply zone, and frequent changes in flow velocity and flow direction were observed, which conformed to the hydraulic characteristics of the mixed water supply zone. It indicates that the prediction results are correct and the method is feasible.