微灌用砂过滤器堵塞与反冲洗效果研究

Study on the clogging and Backflushing Coefficient of the Sand Filters for Micro-irrigation

分析了过滤与堵塞的规律，即过滤时表层堵塞比下层严重．随着过滤运行时间的延续．滤层堵塞由表层逐渐向下层推移；根据反冲洗试验结果，提出了最佳反冲洗强度和最佳膨胀率，并对反冲洗效果进行了实际验证，为正确设计农用砂过滤器提供了设计依据．

The law of filtration andclogging is analyzed. The clogging upper layers is more seriousthan lower lay6rs and it is developed from top to bottom as filtrating time g￣ on. The optimumrate of backflushing and optimum coefficient of expension have been advanced. And the effect ofbackflushing have been verified. These give designers a theory basis for designing and using thiskind of sand filters.