The influence of incorporating leachate on anaerobic biodegradability of domestic sewage

Treating leachate is one of the most important challenges in designing and operating a sanitary landfill. Anaerobic treatment u-sing a mixture of leachate and domestic sewage represents a suitable treatment option having good potential applicability in developing countries. The influence of adding leachate from a domestic sanitary landfill on the anaerobic biodegradability of domestic sewage has been evaluated in this paper. Five samples were evaluated for the study: 100% domestic sewage (DS), 100% leachate (L) and three leachate mixtures (L) with domestic sewage (DS) as follows: 10%(L):90%(DS), 20%(L):80%(DS) and 30%(L):70%(DS). The samples anaerobic biodegradability was monitored for 30 days using methane production accumulation and variation in volatile fatty acid (VFA) concentration and composition. A detailed analysis of chemical oxygen demand (COD) composition was performed at the end of the monitoring period. The results of the study showed that a 10%(L):90%(DS) mixture provided the maximum leachate (L) domestic sewage (DS) combination mixture which could be anaerobically biodegradable with no significantly inhibitory effects. Mixtures using a higher percentage of leachate showed significantly potential inhibition effects on the anaerobic biodegradation of domestic sewage.