Enhancement of an electrocoagulation process for the treatment of textile wastewater under combined electrical connections using titanium plates

Abstract

The performance of an electrocoagulation (EC) process by adding titanium plates (electrooxidation, EO) was studied for the treatment of textile wastewater using combined electrical connections in a single reactor. Aluminum (and iron) and Titanium (Ti) electrodes were fixed in a bipolar (Bp), and monopolar (Mp) structure in the same electrolytic cell. The performance of the reactor was characterized in terms of electrolysis time (RT), current intensity (I), pH, chemical support, inter-electrode distance (IED), and stirring speed (Mrpm). Furthermore, energy and electrode consumption, sludge compaction, operating expenses as well as comparison with the conventional EC process was also examined. The most suitable EC-EO performance was achieved by using Mp Ti-Bp Al plates. Preliminary results showed the following optimal operating conditions: I=0.6 A, pH=6, IED=1cm and Mrpm=500 rpm. The implementation of these parameters on textile wastewater revealed a relatively high removal efficiency of COD (93.5%), TSS (97%), color (97.5%), BOD5 (90%), TDS (89%), turbidity (96%), phenols (99%) and phosphate (97%). The overall operating cost for the process was 1.69 US$/m3. This value was calculated based on the electrode and energy consumption, chemicals, and sludge disposal.