Hydraulic performance of drip irrigation subunits using wastewater from coffee fruit processing

Abstract

The hydraulic performance of the subunits of a drip irrigation system with coffee fruit wastewater was evaluated. The experiment was performed at the Hydraulic, Irrigation and Drainage Experimental Area of the Agricultural Engineering Department, at the Federal University of Viçosa, Viçosa, MG, Brazil. The structure was composed of non-compensable dripper tapes 0.3 m apart. Two irrigation subunits were evaluated: one operating with non-filtered coffee fruit wastewater (NCFW) and another with filtered coffee wastewater (FCFW). Results show that wastewater obtained from coffee fruit presented a greater risk of clogging the drippers, even after they were partial or totally treated by organic filters. The buildup of a biofilm caused by bacteria growth, which interacted with the solids in the wastewater, was the main factor in the clogging of the drippers used for the application of coffee fruit wastewater. The coffee fruit wastewater reduced the flow rate and the water uniformity distribution of the drip irrigation units.