Wastewater Treatment for a Possible Water Reuse in Semi-arid Climate Zone

The main objective of this work was to investigate on the possible conjunction of electrochemical processes (electrooxidation and electrocoagulation) for the treatment of dyes bearing wastewater for a possible valorisation in irrigation fields. The used methods were also tested separately to see the extent of the treatment yield of each technique. Experiments were conducted in laboratory confectioned reactors under different operating conditions. Obtained results under the optimized experimental conditions show that both electrooxidation and electrocoagulation applied separately exhibited a limited performance towards suspended matter, chemical oxygen demand, color and turbidity removal. In fact, neither the electrooxidation nor the elecrocoagulation enabled to meet the discharge criteria of wastewater release into the receptor media. It was also noticed that the electrocoagulation favored the removal of suspended matter (95%) whereas the electrooxydation lead to an efficient color removal (96%). On another hand, conjunction of these processes enabled a high pollution reduction rate reaching nearly 98% in terms of color, chemical oxygen demand and suspended matters. The obtained results also indicate that the combination of the above mentioned processes reduced significantly the phytotoxicity of the wastewater and enhanced considerably its biodegradability exhibited through the drop of COD/BOD5 ratio. Based on this, it was suggested that conjunction of electrochemical processes could be another alternative for the enhancement of pollution removal efficiency from textile wastewaters. Furthermore attempts were made to reuse the treated wastewater in the irrigation field. The results indicate that electrochemically treated wastewater showed no phytotoxicity and no cytotoxicity toward the tested plants and microorganisms and therefore can be thought about for a possible exploitation to irrigate certain plants and trees.