不同过滤方式下沉积在滴灌带中的颗粒粒度分布研究

Study on Particle Size Distribution Deposited in Drip Irrigation Tape under Different Filter System

水源中的固体颗粒在灌溉过程中随着水流沉积在滴灌管（带）中并引起滴灌系统的堵塞。利用田间灌溉用过的滴灌带作为研究对象．选用了堵塞明显的与堵塞不明显的两类滴灌带，每一种滴灌带从进口分为5段，取出每一段的泥沙颗粒利用激光粒度分布仪对沉积在滴灌带中的颗粒粒度进行分析。分析结果得出：不管滴灌带是否堵塞，较大颗粒都沉积在第2～4段，第1、5段的颗粒粒径相对较小。由于抉沙能力随水流流速迅速减小，在第2、3段的滴头被堵塞的可能性较大。从不同的过滤方式对比分析得出：单独的网式过滤器不能作为滴灌系统的过滤设备，两级网式过滤器可有效减小滤后水中颗粒的粒径。

The solid particles in water will deposit in drip irrigation tape （tube） and clog drip irrigation system. In this paper, the drip irrigation tape that had been used in farmland was used as the research object, and two kinds of irrigation tape, including obviously clogged tape and not obviously clogged tape, were chosen. Each kind was divided into five sections from the entrance. The particle size distribution deposited in drip irrigation tape was by analyzed by Laser Particle Size Analyzer. The result indicated that no matter the drip irrigation tape was clogged or not , the bigger size of particles were deposited in the second to the fourth parts of the tube , while the smaller ones are deposited in the beginning and end parts. Because the sediment-carrying capacity rapidly decreased as the flow reduced, the probability of clogged in the middle parts of the tube is higher. Through comparing different filter systems, it can be concluded that the single screen filter is not enough as filer system for drip irrigation system and two-stage screen filter can effectively reduce the particle size in the water after filter.