北方某城镇净水厂滤池的运行评估

Evaluation on Operation of Water Treatment Plant's Filter in Northern Towns

以北方某城镇净水厂滤池为研究对象,在水厂正常生产的情况下,以滤速、连续滤后水浑浊度、滤后水中颗粒数、反冲洗废水浑浊度、反冲洗强度、反冲洗滤层膨胀度为评价指标,开展滤池的运行评估.结果表明:煤砂双层滤料滤池具有运行周期长、出水浑浊度低且稳定的优点;3座评估滤池的滤速不同,建议通过调整滤池出水管控制阀的开启度,实现同一水厂不同滤池滤速的同一性;滤池实际的反冲洗强度与设计值差别较大,建议降低反冲洗强度,将滤池的膨胀度稳定在20%~30%;滤池的反冲洗时间有待进一步的优化,根据反冲洗废水浑浊度分析的结果,水冲洗时间可以考虑从7 min减少到4 min.

In the production of a water treatment plant's filter in northern town,operation management of the filter were evaluated by filtration velocity,taking turbidity and particle counts of filtered water,turbidity of backwash water,backwashing water strength and backwash bed expansion as evaluation indexes.The results showed that anthracite-sand filter had the advantages of longer operation period,low and stable turbidy of effluent.Filtration velocity of the three evaluated filters were different.It was suggested that the uniformity of filtration velocity of different filters in the same water treatment plant could be achieved by adjusting the valves of the filters.There was a big difference between actual backwashing water strength and the designed values.It was suggested that backwashing water strength should be reduced and the expansion of the filter should be stabilized between 20%and 30%.At last,backwash duration in minutes of the filter needed to be further optimized.According to the results of turbidity analysis of backwash water,backwash duration in minutes could be reduced from 7 min to 4 min.