Treatment of the surface water by electrocoagulation-electroflotation process in internal loop airlift reactor: Conductivity effect on turbidity removal and energy consumption

The aim of this paper is the potabilisation of surface water by an electrocoagulation-electroflotation process in internal loop airlift reactor. the initial turbidity of the water to be treated is fixed at 107 ntu,a value generally found in surface waters. the tests were performed in airlift reactor of rectangular shape with an internal loop with a useful volume of 850 ml. the evaluation of the performance of the treatment is carried out by measuring,during the electrolysis time,the effect of the initial electrical conductivity on the reduction of the turbidity and the electrical energy consumption. during the treatment,three stages are distinguished: lag,reaction,and stable. in the reaction step,the electrocoagulation-electroflotation kinetics is rapid and it increases with the increase of the initial electrical conductivity of the solution σ0. the processing time depends on the duration of the reaction step which decreases as σ0 increases. to achieve a turbidity abatement of40%,the electrolysis time required for an initial conductivity solution σ0 of 106 μs.cm-1 is approximately 2.5 times the time for a solution of σ0 equal to 351 μs.cm-1.this also applies to a reduction of 70% and 87%. as for energy consumption,it increases by about 30%. a correlation has been established,between the electrical energy consumed per m3 with the initial conductivity of the solution and the electrolysis time. © 2017,university of mohammed premier oujda morocco.