微灌条件下三种过滤器过滤效果试验研究

为了探索砂石、筛网和叠片过滤器对黄河泥沙的过滤效果及其差异性,在不同过滤流量下进行了室内模型试验,并对比分析了过滤后水浊度、颗粒质量浓度、水头损失、瞬时流量等指标。结果表明,砂石过滤器过滤后水浊度和颗粒质量浓度低于筛网和叠片过滤器,且砂石过滤器过滤后水的水浊度和颗粒质量浓度变化曲线较为稳定,筛网和叠片过滤器的浊度滤除比率和颗粒质量浓度滤除比率均低于砂石过滤器。砂石过滤器截留的泥沙粒径分布均匀,而筛网和叠片过滤器截留能力体现在大粒径,因而砂石过滤器更能充分实现过滤功能。砂石过滤器水头损失随时间呈现递增趋势,而筛网和叠片过滤器变化幅度不大,分析认为后者未能充分截留泥沙,判定水头损失小不代表过滤效果好。综合可知,砂石过滤器过滤黄河泥沙效果优于筛网和叠片过滤器。

Experimental Study on the Efficacy of Sand Filter,Screen Filter and Disc Filter for Removing Silts from the Yellow River Water for Micro-Irrigation

The objective of this paper was to investigate experimentally the efficiency and difference in using sand filter,disc filter and screen filter to remove the silts from Yellow River water under different filtration rates in a laboratory test.In each experiment,we measured the turbidity,particle concentration,head loss and flow rate after the filtration.The results showed that the turbidity and particle concentration in the sand filter were lower than that in the screen filter and disc filter;the particle concentration after filtered by the sand filter was relatively stable,while the turbidity filtering ratio,particle concentration and filtering ratio in the disc filter and screen filter were lower than that in the sand filter.Analysis of the particle size distribution showed that the sizes of the particles intercepted by the sand filter was uniform,while the screen filter and disc filter only intercepted large particles.Therefore,the sand filter was more efficient for removing particles.The water-head loss in the sand filter increased with time,while the head loss in the disc and screen filters was independent of time as there was less particle accumulation in them.For removing the silts from Yellow River water,the sand filter was superior to the screen and disc filters.