Flow rate changes of drippers with dilutions of treated water produced by oil exploration in the Brazilian semiarid region

The liquid residue called “produced water” from the exploitation of oil in the ground and sea is generated in large volumes and has significant polluting potential. In the Brazilian semiarid region, this liquid can be applied to the agricultural lands, if properly treated and applied to the soil by dripping. It is an alternative that can mitigate water scarcity and impacts on the environment. However, the vulnerability of drippers to clogging is a problem and can be mitigated with the dilution technique. The flow rate changes of drippers for the application of dilutions of produced water treated (PW) with underground water (UW) was analyzed. The experiment was conducted in a completely randomized split-split-plot design with three replications. Plots consisted of treatments (D1: 100% of UW, D2: 90% of UW and 10% PW, D3: 80% of UW and 20% of PW, D4: 70% of UW and 30% of PW and D5: 60% of UW and 40% of PW). The split-plots consisted of types of drippers (G1: 1.6 L h-1, G2: - 1.6 L h-1, G3: 1.7 L h-1) and split-split-plots consisted of evaluation times (0, 40, 80, 120 and 160 h). Flow rate (D) and flow rate coefficient of variation (FCV) were taken every 40 hours untill 160 h. The results showed that the G3 emitter was the most resistant to clogging. The dilutions D2 and D3 provided the lowest losses in hydraulic performance in the drip units. The highest rates of clogging occurred in the G2 emitter operating in the D5 dilution