Seog Ku Kim*, Saburo Matsui*, Sandeep Pareek* and Yoshihisa Shimizu*

* Research Center for Environmental Quality Control, Kyoto University

+ Correspondence should be addressed to Seog Ku Kim:
(1-2 Yumihama, Otsu City, Shiga, 520-0811, Japan)

Abstract

In our previous experiments four simulated landfill column reactors were operated for 700 days under sulfidogenic and methanogenic conditions to study the methane gas emission trends during the degradation of model solid waste. Results from the simulated landfill column reactors provided only a general trend and nature of degradation of the model solid waste loaded in the reactors. Explicit results regarding the efficiency of the different rectors to degrade the model solid waste could not be inferred. Thus to understand the degradation of cellulose (a major component of model solid waste) under sulfidogenic and methanogenic conditions vial batch experiments were carried out and the results are presented. The leachate from either reactor R1 (partially saturated methanogenic reactor) or reactor R3 (fully saturated sulfidogenic reactor) was used to inoculate the vials. According to the results of vial batch experiments, the degradation of cellulose was faster under sulfidogenic condition than methanogenic conditions. Acetate accumulated during the sulfate reduction of cellulose under sulfidogenic conditions. The electron flow under sulfidogenic conditions was dominated by sulfate reducing bacteria. Finally, methane gas was effectively suppressed under sulfidogenic conditions.

Key words: landfill, sulfidogenic, methanogenic, electron flow, cellulose