Characterization and electrocoagulative treatment of landfill leachates: A statistical approach

The purpose of this research was to comprehensively evaluate the characterization and the optimization of electrocoagulation for sanitary landfill leachate treatment in Aksaray/Turkey. This is the first study conducted with regard to both the characterization and the electrochemical treatment of leachate in Aksaray province. For this purpose, leachate samples were collected in situ at a monthly interval for a period of 13 months and physicochemical parameters and heavy metals were monitored. Meteorological data were also recorded for the same sampling period to calculate the leachate production amount (LPA) and to correlate between the physicochemical parameters. The results were statistically analyzed by using Pearson correlations analysis, SPSS software. In the next step, the leachate was treated by the electrocoagulation (EC) method with aluminum and iron plate electrodes together in a laboratory-scale batch process. The effects of process variables such as current densities, time, and pH were investigated for chemical oxygen demand (COD) removal. Stepwise regression analysis was done for determining which variable, acting independently, best explains or predicts the variation in the removal efficiency of COD. As a result of this study, a feasible model containing variables of the electrocoagulation process on COD removal was derived using stepwise regression analysis.