Landfill Leachate Characterization of AKSARAY Province and Electrochemical Treatability

Abstract

In this study, characterization and treatability with electrocoagulation (EC) method of leachate from landfill of Aksaray Province, Turkey were investigated. Physical and chemical characteristics of leachate samples taken from same location were performed about one year as monthly. As a result of thirteen-month long characterization studies, parallel literature, it was observed that biochemical oxygen demand (BOD₅)/ chemical oxygen demand (COD) ratio within the range of 0.44-0.8 in fresh landfill. In fresh landfill area, pH, temperature, total organic carbon (TOC), COD, BOD5, alkalinity (TA), total nitrogen (TN), total kjeldahl nitrogen (TKN), total suspended solid (TSS), chloride (Cl-), sulphate (SO4^2-) and heavy metals such as arsenic (As), boron (B), barium (Ba), calcium (Ca), cadmium (Cd), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), mercury (Hg), potassium (K), magnesium (Mg), sodium (Na), nickel (Ni), lead (Pb) and zinc (Zn) were analyzed. After the characterization study, treatment of the leachate by electrocoagulation method with aluminum (Al) and iron (Fe) plate electrodes that was using together was investigated.

In addition to leachate characterization and develop current experiences of treatment methods, COD removal from leachate using electrocoagulation method also carried out in the scope of this study. In EC removal of COD, the effects of current intensity and retention time parameters were investigated. In leachate samples where COD concentrations were even higher than 5000 mg/L, a successful removal of COD was accomplished by electrocoagulation, electroflotation and electrooxidation mechanism in completely mixed batch reactor conditions. COD removal efficiency was over 75% with Al and Fe electrodes in the EC reactor which was operated during the retention time of 60 minutes. According to the results, the most acceptable current intensity for COD removal was determined to be 5,08 mA/cm2 and the most acceptable treatment time was determined to be 5 minute. It is observed that EC process may be an acceptable solution for the pre or post treatment of leachate.