Martha Minale Yeshanew
University of Cassino and Southern Laizo, Italy
Title: Enhanced biogas and fertilizer production through anaerobic co-digestion sanitary wastewater and kitchen solid waste under ambient temperature: Waste generated from condominium house
Biography
Biography: Martha Minale Yeshanew
Abstract
Addis Ababa is one of the fastest growing cities where high urbanization has become a challenge. The municipality has launched a huge condominium housing program in response to the housing shortage problem in the city. However, sanitary wastewater and solid waste management are the critical problems to those houses. The wastes were collected and evaluated for its biogas production and fertilizer potential to solve the foreseen waste management problems. The physicochemical characteristics of the collected wastes were determined. A laboratory scale batch anaerobic co-digestion of both wastes with different mix ratio of 100:0, 75:25, 50:50, 25:75, and 0:100 (sanitary wastewater: kitchen organic solid waste by volume) were carried out at ambient temperature for 30 days. The amount of biogas produced during the digestion period for those mixing ratios were compared. The physicochemical characteristics showed that kitchen wastes were rich in nutrients and easily biodegradable organic compounds. While sanitary wastewater contains high amount of nitrogen and trace metals, which makes the co-digestion of the two waste more attractive. Highest cumulative biogas yield of approximately 65.6L were obtained from 25:75 mix ratio, followed by 50:50,100:0, 25:75, and 0:100 with biogas productions 52.7, 50.0, 23.7 and 9.5 L, respectively. The percentage of methane gas during the study period was between 19.8-62.8%. With regard to the fertilizer potential of the digested sludge; composting and sun drying process were effective and helpful for land application by completely inactivating the pathogen.