An experiment was conducted at the Laboratory of Irrigation in the Department of Rural Engineering at ESALQ, in order to evaluate the use of different chlorine doses in recovering the original flow rate for total and partial emitter clogging. Five Netafim drippers were evaluated: Streamline 100, Ram 17L, Dripline 2000, Tiran 17 and Typhoon 20. Four chlorine levels, 150, 300, 450 and 600 mg L-1, were tested. A regular water source for irrigation was used. Sodium hypoclorite (12%) was used as the source of chlorine supply. The chlorination process took place during 60 min and after this period the solution remained inside the hose for 12 h without flow. Then the flow of each emitter was measured. Mean discharge, variation coefficient of mean discharge, percentage of number of emitters in different classes of discharge reduction were analyzed. For all kinds of drippers, except the Streamline, the chlorine treatment improved the discharge rate. For the Dripline model the treatment reduced the uniformity emission, while eficiency was increased after the second application for the Tiran model.
sodium hypoclorite; reclaiming; drip
