Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE credits
Anaerobic digestion is the process that generates the biogas. This process can be used successfully to treat municipal organic solid wastes and kitchen waste to produce valuable end products, such as methane gas and fertilizer.
This research aimed at finding out how a large scale market place in Ratmalana, a city close to capital, Sri Lanka can successfully utilize its organic waste as opposed to land filling or dumping. The study specifically aimed at determination of composition and characterization of waste produced over a season followed by possibility of biogas generation using anaerobic digestion process for the use in a nearby University restaurant.
The study revealed that the composition of the market waste as follows; vegetable wastes 45%, fruit wastes 35% , packing materials 15% and restaurant waste/food waste 3%, The materials in the form of stones, plastics, wood etc. was less than 1.3 % of the waste quantity. Total average waste production per day was around 1 ton. The average pH value, percentage of water present, percentage of solids and percentage of volatiles present in fruits and vegetable were 6.38, 92%, 8.08% and 6.18% respectively.
BiomethanePotential (BMP) in respect to fruit and vegetable waste and Food waste were found to be 0.3 and 0.56 m3 CH4/kg respectively. The biodegradability of fruit and vegetable waste and food waste were calculated as be 59.3%, 83.6%, respectively.
According to characteristics and Biomethanepotential of the feedstock the biogas production rate was estimated as 21.75m3/day. A pilot scale digester was designed with a volume of 52.57 m3 which would generate 8.72 m3 of biogas per day, considering practical limitations. It was estimated that at least three Continuous flow biogas digesters of the same volume of are needed to treat all the waste produced. According to the study the quantity of waste produced at the market place can be successfully used to generate one fourth of the energy requirement of the university restaurant
2010. , 52 p.
Jayasuriya, Jeevan, Dr.