Fertilization uniformity is an important index to evaluate the performance of the micro irrigation system and understanding the hydraulic performance of water treatment equipment in drip irrigation system is a prerequisite to ensure the stable operation of the system. For the popularization and application of water and fertilizer development of drip irrigation technology, we carried out a test to investigate the effect of fertilization proportion and fertilization-water ratio on clogging of filter by fertilizer pump in microirrigation system. The pump selected was commonly used 120 mesh (diameter 0.13μm) screen type and disc filter. The test was carried out in the Key Laboratory of Arid Agricultural Water and Soil Engineering of Ministry of education, the Northwest A&F University. The fertilization proportion was 2％, 3％ and 4％. The inhaled fertilizer and water ratio was 1:4, 1:5 and 1:6. Water samples were collected to determine the fertilizer concentration at fertilization pump outlet. The concentration of phosphate was determined by an ion conductivity instrument. The uniformity of fertilizer concentration at outlet was assessed by Christensen coefficient, distribution uniformity and statistical uniformity. The results showed that the fertilizer concentration at outlet was different significantly among the 9 treatments. It increased with the increase of fertilizer proportion and inhaled fertilizer and water ratio. At the fertilizer proportion of 4％, the Christensen coefficient significantly differed among the treatments of fertilizer and water ratio. No significant difference was found for the Christensen coefficient at the fertilizer proportion of 2％ and 3％. Thus, the high fertilizer proportion could greatly affect the fertilizer concentration uniformity at outlet and we do not recommend the high fertilizer proportion. The water head loss of screen filter became stable at about 3 min for the treatment of the fertilizer concentration equalling to or higher than 0.117％. When the concentration smaller than 0.117％, the water head loss was less than 0.5 m for the screen filter. For the disc filter, the water head loss increased slowly when the fertilizer concentration at outlet was not smaller than 0.067％. But, when the fertilizer concentration at outlet was smaller than 0.067％ the water head loss was less than 0.5 m. To avoid filter clogging at a short time, the fertilizer concentration at outlet smaller than 0.117％ and 0.067％ was recommended respectively for the screen filter and the disc filter. The range of water head loss for the screen filter (0.09-7.75 m) was higher than that for the disc filter (0.32-3.88 m). With the increase of fertilizer concentration at outlet the surface attachment weight was not significantly different for the screen filter but significantly different for the disc filter. The max surface attachment weight was as 11.4 times as the min one. The flow rate of the screen filter decreased from 0.4 m3/h to 0.2 m3/h when the fertilizer concentration at outlet was the highest (0.296％). The flow rate of the disc filter decreased from 0.4 m3/h to 0.3 m3/h when the surface attachment weight increased to 4.56 g. The anti-clogging performance of disc filter was much better than the screen filter when the maximum average fertilizer concentration at outlet was 0.296％. The research can provide the technique support for the popularization and application of integrated water and fertilization technology of drip irrigation equipment.%为研究微灌用施肥泵施肥比例与肥水比对过滤器堵塞的影响,该文以叠片和网式过滤器为研究对象,结合比例式施肥泵的施肥特点及性能,通过调节不同施肥比例(2％、3％和4％)与吸入的肥水比(1:4、1:5和1:6)对过滤器在施肥条件下的水头损失、总过水流量及滤网(芯)附着物质量进行分析.结果表明:网式和叠片式过滤器对出口肥液浓度的使用范围不一致,网式过滤器适用于肥液平均浓度在0.117％以下,叠片式过滤器适用于肥液平均浓度在0.067％以下.随着肥液浓度的增大,滤网表面附着物质量差异不显著,滤芯叠片上附着物质量差异显著,最大附着物质量是最小附着物质量的11.4倍;叠片式过滤器抗堵塞性能远远优于网式过滤器,当肥液平均浓度最大为0.296％时,叠片滤芯附着物质量是网式滤网质量的4.75倍,总过水量比网式过滤器大0.1 m3/h.研究可为水肥一体滴灌设备技术的推广和应用提供依据.
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