Author(s)

M.M.H. OLIVER, D. PEZZANITI1, & G.A. HEWA

Abstract

Emitter clogging in drip irrigation system is a very common problem when used with reclaimed water. The suspended solids from treated water are the major elements of clogging mechanism. Coupled with bacterial biofilms, these particulates can reduce the flow of emitters by creating barriers in the flow path. This experimental study reports the performance of three types of pressure compensated emitters in a drip irrigation system. Reclaimed water with a sediment load of 10 mg/l was supplied in the system throughout the experiment. Four ranges of particle sizes (0–45, 45–90, 90–150, and 150–300 µm) were used during 770 h of intermittent irrigation. Low flow emitters (<2 l/h) were found to be clogged quicker than those with higher flow rates. Though flushing of the system did not help in discharge recovery of the partially clogged emitters, it helped regain the lateral flow. The interior geometry of biofilms was found to be built only by the smaller particles. Larger particles (>50 µm) only appeared around the perimeters of matured biofilms making the surface topography very coarse and undulating.

Keywords

Clogging, emitters, particle size, reclaimed water, suspended load.