我国不同区域水源水拉森指数比较分析

Comparison and analysis of the Larson ratios of source waters in different areas of China

目前远距离调水已经成为解决区域水资源不足的一项重要措施。但在水源切换时,切换前后水源水的腐蚀性如果存在显著差异,可能会因腐蚀加剧而出现"黄水"或"红水"现象。因此,了解不同区域、不同类型水源的腐蚀性差异,对于科学合理地进行水资源调配具有重要意义。拉森指数(LR)是目前评价水质对铁质管网腐蚀程度的常用方法。本研究以14个城市的26个水源水为研究对象,对模拟常规工艺处理后的滤后水进行了水质分析,并计算出其拉森指数。结果表明,相对于湖库水和地下水,河流水的拉森指数偏高,有44%的河流水拉森指数大于1,具有较强的腐蚀倾向。按区域分华东和中南地区、按流域分黄河和珠江流域的水源水拉森指数平均值大于1,水源切换条件下应关注其腐蚀性情况。

Long-distance water diversion has become the most important measure to solve the problem of water-deficient areas recently. However, if the corrosivity of the new source water changes significantly after source water switch, the distribution system may be corroded by the new water and yellow or red water may occur. Consequently, in order to allocate water resources rationally, it is very important to investigate the corrosive differences of source waters in different areas and of different water types. Larson ratio is a usual index to estimate the corrositity of source waters. 26 source waters in 14 cities were sampled and analyzed after simulate conventional water treatment processes and Larson ratios of the water samples were calculated. The results showed that the Larson ratios of river waters were higher than those of lake and ground waters. The Larson ratios of 44% of river waters exceeded 1, showing the strong corrosivity of these waters. Furthermore, the mean values of Larson ratios of the waters in the Eastern China, the South Central China, the Yellow River Valley, and the Pearl River Basin all exceeded 1. And the corrosivity of these waters should be paid more attention when the source waters switch.