Horizontal roughing filter for reducing emitter composite clogging in drip irrigation systems using high sediment water

Composite clogging substance is an inevitable issue in irrigation systems that use high-sediment water (HSW), consequently leading to emitter clogging, which may damage the whole irrigation system. So far, settling tanks allow particle deposition before water is applied in the drip irrigation systems, so they reduce particle load and therefore clogging risk is reduced. However, these tanks do not always perform properly, particularly when controlling biologging and organic matter clogging. This study proposed using a Horizontal Roughing Filter (HRF) to relieve composite clogging in irrigation systems using HSW. Results revealed that HRF reduced Sediment concentration (SC), Chemical Oxygen Demand (CODcr), Total Organic Carbon (TOC), and Biochemical oxygen demand (BOD5) by 73.6-89.6%, 8.1-62.2%, 15.3-51.8%, and 22.8-53.1%, respectively. In addition, compared with control treatment (CK), HRF decreased the clogging substance of lateral and emitter by 32.4-37.6% and 25.5-29.4%, respectively, which obviously alleviated the risk of emitter clogging. Finally, compared with CK, HRF increased the Christiansen of Uniformity (CU) of drip irrigation system and average discharge variation ratio (Dra) 9.2-27.1% and 12.3-22.5%. Moreover, the filter performance of HRF under medium thickness of 60 cm was obviously higher than those with thicknesses of 20 cm and 40 m, only slightly lower than those with thicknesses of 80 cm. The results demonstrated that HRF is an effective filtration treatment with great potential applications for controlling the composite clogging in irrigation systems using high-sediment water.