南随塘河pH值超标原因分析和解决方法

The Causes and Solutions to Excessively High pH of Water of the South Suitang River

自2007年以来,每年夏季某石化工业区南随塘河水质经常出现pH值碱性超标。经试验证实了其原因之一是循环水场排污水质pH值较高,加上夏天气温高,河水蒸发浓缩和河水流速缓慢,致使水处理剂有机结构打破,产生更多的碱性物质;原因之二是循环水场排污水和沿岸各排口排放的清下水均含有不少有机物,使水体富营养化,从而河水中藻类大量繁殖,藻类的光合作用引起了溶解氧浓度的升高,影响了水中的碳酸盐平衡,从而导致pH值的升高。对原有的pH值与溶解氧的关系式进行了修正,建立了更符合实际情况的新关系式。建议循环水场排污水采用微滤膜和反渗透膜的双膜法处理,处理后的回用水电导率小于300μS/cm时送回循环水系统,剩余浓缩污水可排至生化装置进一步处理。对于藻类繁殖问题,建议通过磁处理法灭藻、控制营养和及时捞取等方法解决。

Since 2007 ,the pH of water of the south Suitang River has often been excessively high in a petrochemical industrial zone every summer.Experiments showed that the causes of the high pH values were： firstly ,due to the combination of factors such as the high pH of sewage from the circulating water field,high temperature in summers,river water concentration by evaporation structure of water treatment chemicals was broken,resulting in sewage from the circulating water field and the clean drainage and the slow flow of river water, the organic more basic substance produced ; secondly,the from the sewers along the river both con- tained a large amount of organic substance ,eutrophicating the water body ,resulting in a propagation of alga in the river.The pho carbonate balance of tosynthesis of alga led to a rise in the concentration of dissolved oxygen,upsetting the the water and thereby resulting relational expression of the pH and dissolved oxygen cific conditions.It is recommended that the circulating in an increase of the pH.Researchers revised the former and established a new one more in line with the spe- water field use the double-membrane method （microfiltration membrane and reverse osmosis membrane） to treat its sewage.When the electrical conductivity of the treated recycled water is less than 300μS/cm,the water can be returned to the circulating water system and the remaining concentrated sewage can be drained to a biochemical treatment unit for further treatment.The recommended methods for preventing alga from propagating include magnetic handling,nutrition control and timely dredging