Anti-clogging evaluation for drip irrigation emitters using reclaimed water

• DOI: 10.1007/s00271-016-0530-8
• Publication Date: 2016-12-02T10:48:38Z
• Authors: Bo Zhou; Yunkai Li; Peng Song; Yunpeng Zhou; Yang Yu; Vincent Bralts
• Keywords: Clogging; Reclaimed water; Soil gradation

Emitter clogging has a direct impact on the required operating time and benefit of a drip irrigation system, especially when using reclaimed water. Thus, accurately evaluating its anti-clogging ability is important to select an appropriate emitter under specific conditions. In his paper, a drip irrigation emitter clogging experiment was carried out, and the dynamic outflows of 14 emitter types using 3 kinds of reclaimed water and the groundwater in the experiment station in Tongzhou, Beijing, were tested. Then, the drip irrigation emitter anti-clogging ability evaluation index (I a ) was proposed, based on the measured emitter clogging characteristics. I a ranked in consistent with average discharge variation rate (Dra) among different types of emitters. Thus, I a is a valid performance indicator to evaluate anti-clogging ability, and an emitter with a relatively large value of I a has a better anti-clogging ability. According to the calculated I a , the same type of emitter showed better anti-clogging ability with the groundwater than with the reclaimed water, while cylindrical emitters were more likely to clog than flat emitters. Additionally, I a was mainly affected by flow path length (L), flow path width/depth ratio (R W/D ) and average near-wall water shear force (τ), as I a increased with shorter L, smaller R W/D and larger τ. Furthermore, the quantitative estimating model of I a was established through dimensional analysis and was predicted by an emitter’s rated outflow (Q) and flow path geometrical parameters (L, W and D).