EFFECT OF FLUSHING FREQUENCY WITH SULFURIC AND PHOSPHORIC ACIDS ON EMITTER CLOGGING

摘要

Flushing is an important maintenance task that removes accumulated particles and suspended salts in microirrigation laterals that can help to reduce clogging problems, the aim of this research is to find out the most suitable and efficient maintenanceprogram which could counteract the problem of emitter clogging under Egypt conditions. Four maintenance program were studied MP_1 (flushing with sulfuric acid 95%), MP_2 (flushing with phosphoric acid 95%), and MP_3 (A new net work attitude which represent the control), the effect of four flushing frequency treatments were studied under MP_1, and MP_2 (weekly (T-i), bi-weekly (T_2), monthly (T_3) and at the end of growing season (T_4)), the maintenance programs were applied surface drip irrigation system. The irrigation system had inline emitters' 50cm apart, non-pressure compensating, placed in laterals 60 m long. Seven criteria's were used to evaluate the efficient of maintenance programs emission uniformity (EU), distribution uniformity (DU), partial clogging ratio (CR_P), complete clogging ratio (CR_C), emitter flow variation (Ovar), Pressure uniformity (U_P) and Pressure variation along laterals (AH). The MP_1T_1 was the best maintenance program it achieved highest values and it decreased gradually with increasing flushing duration till MP_3 the worst maintenance program applied through farmers to minimize the cost and quantity of lost water, which leads to decrease the systems performance significantly besides the increment of emitters clogging percentages according to evaluation parameters. The suggested maintenance programs as a result of this research are MP_1T_1, MP_1T_2, MP_2T_2 and MP_2T_1.