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Citation: Shwetmala, Chanakya HN and Ramachandra T V, 2014. Anaerobic Degradation Pattern of Urban Solid Waste Components, In Waste Management and Resource Utilisation, Sadan K Ghosh (eds.), Pp 332-336, Oxford Publishing House, Kolkata.
The anaerobic digestion characteristics of ten
specific types of the fermentable fractions commonly occurring in urban solid waste (USW) in
Bangalore were examined. The rate of decomposition, the pattern of fit and extent and rate of
biogas production from these potential feedstocks are analyzed and reported. More specifically,
decomposition of vegetables wastes [cauliflower, onion, flat beans, radish and peas] and dominant
fruit wastes [banana, sweet lime (Mosamby), orange, papaya and watermelon] were studied. Each
of the fruits and vegetables were fermented singly and as mixtures by biological methane potential
(BMP) assay to determine the process stability during anaerobic digestion. Typical mixtures of
these vegetables and fruits were also fermented anaerobically to determine BMP. At periodic
intervals samples of biogas produced were analyzed and their gas composition determined to
monitor the decomposition rates and process health. Citrus fruits, orange and sweet lime had 95%
and 94% of volatile solid, respectively, followed by peas shells (94%) and onion (92%). Among
the ten feedstocks, flat beans, banana and citrus fruits (orange and Mosamby) showed a
decomposition pattern similar to each other with a rapid initial decay pattern. The biogas
production ranged from 205 to 616 ml/g of TS. Orange and sweet lime showed low gas production
levels. Pea shells, flat bean, cauliflower and radish wastes showed a high gas production whereas
banana peel had showed a moderate gas production level (c.465 ml/g TS). Such results provided
an insight on the extent and rates of the major biodegradable organic fractions of urban solid
waste in anaerobic degradation and likely process control required.
Keywords:Anaerobic degradation, Organic waste, BMP, Biogas, Decomposition rate.
