Author(s)

C. Can Yarimtepe, N. Ayman Oz

Abstract

Anaerobic treatment methods have been preferred for landfill leachate which has a high organic content. However, the wastewater is also characterized as a complex content and, therefore, stability problems can occur during the operation of anaerobic reactors due to the complex structure of the wastewater. The aim of this study is to investigate the integration of an ultrasound process for leachate as a pretreatment prior to anaerobic batch reactors to increase hydrolysis rate and biogas production. After 45 min sonication, the ratio of sCOD/tCOD was increased by 32% compared to raw leachate at 400 W/l. These results showed that ultrasonic pretreatment has a significant effect on converting particulate organic matter to soluble organic matters. During the anaerobic batch tests, biogas production and methane content are increased by 33% and 15% in pretreated leachate and the raw leachate, respectively. The increases can be attributed to the improvement on biodegradability of leachate and increase in sCOD concentrations by ultrasonic pretreatment. As a conclusion, the increase in COD solubilisation by sonication enhanced biogas production and methane yield in anaerobic batch tests in leachate samples.

Keywords

landfill leachate, anaerobic treatment, ultrasound, biogas, energy