This study aimed to analyze the effect of different operating pressures in the coefficient of flow variation (CVQ) in drip irrigation systems operating with cashew nuts wastewater. The experiment design was completely randomized with three replicates in a split plot scheme, with service pressures (70, 140, 210 and 280 kPa) on plots, models emitters (G1, G2 and G3) on subplot and operation time (0, 20, 40, 60, 80, 100, 120, 140 and 160 hours) on subsubplots. The CVQ of the irrigation units and the physico-chemical characteristics of wastewaters were measured every 20h until the operating time of 160h. The results indicated that pH, calcium, magnesium, manganese and suspended solids of the cashew nuts wastewater represent risk of drip clogging; partial clogging of drippers caused an increase in the CVQ of the irrigation units; and irrigation units that worked at P1 (70 kPa) service pressure showed higher levels of drip clogging than the others, due to the lower flow speed of wastewater within the drippers.
reuse; trickle irrigation; clogging
