摘要
过滤器是微灌工程中处理含沙水源的重要设备,在预设细过滤网内外压差的条件下对微灌用自吸式自动过滤器的过滤和反冲洗性能进行了试验研究。在过滤过程中,细过滤网内表面的泥沙含量和内外压差值随过滤时间增长不断增多,当压差值大于预设压差值时,需对过滤器进行反冲洗。若预设压差值过大,排污时间间隔变长,细过滤网将承受较大压力差而严重影响使用寿命;相反,过滤器的过滤时间较短,频繁排污,影响泥沙的过滤效果,因此如何设置细过滤网内外压差值显的尤为重要。通过理论计算得出细过滤网内外预设压差值的变化范围为0.021~0.086 MPa,并对80目的自吸式自动过滤器进行了试验,结合过滤时间、过滤流量、水头损失等因素,预设压差值设为0.08 MPa时过滤效果较好。
A filter is an essential equipment dealing with the irrigation water containing sand in micro-irrigation projects.By predicting pressure between the inside and the outside of the thin filter screen,the filtration and backwashing characteristics of the automatic self-suction filter in micro-irrigations are studied.In the process of filtering,the sand in the inner surface of the filter screen gradually increases as the filtering time goes on,resulting in the increase of the pressure between the inner and the outer.However,the filter needs backwashing when the pressure is greater than the default value.If the default value is too large,the filtering time will become longer,but it will decrease the life of the filter screen because of enduring greater pressure.On the contrary,the filtering time will be shorter,but backwashing will become frequent,and it will also influence the efficiency of filtration,so how to make the default value becomes very important.Through the theoretical calculation,it is shown that variety of the default value between the inner and outer filter screen is0.021~0.086 MPa.Through the experiment with the 80 screen automatic self-suction filter,considering filtering time,filtering flow,head-loss etc,it is concluded that the filter can work very efficiently when the default value is 0.08 MPa.
出处
《中国农村水利水电》
北大核心
2010年第4期50-53,共4页
China Rural Water and Hydropower
基金
自然科学基金项目(50909062)
关键词
微灌
过滤器
压差预设值
过滤与反冲洗
micro-irrigation
filter
default value
filtration and backwashing
