TITLE:
Analysis of Adapted Sewage Sludge Treatment and Disposal Routes in Bujumbura, Burundi
AUTHORS:
Aaron Bizimana, Bing Wu, Aicha Abdallah Idriss
KEYWORDS:
Sludge Management, Environmental Impact, Policy, Energy Recovery, Sustainability
JOURNAL NAME:
Open Access Library Journal,
Vol.8 No.4,
April
29,
2021
ABSTRACT: The disparities found in studies on sewage sludge management, aggravated by the high financial investment required, may lead to decision-making uncertainty and hesitancy. This research, basing on seven different sludge treatment and disposal routes that are widely used in China (thickening-anaerobic digestion-dewatering-land application, thickening-condi- tioning-dewatering-sanitary landfill; thickening-conditioning-dewatering- anaerobic digestion-land application, thickening-conditioning-dewatering- drying-incineration; thickening-conditioning-dewatering-drying-land application; thickening-conditioning-dewatering-incineration-sanitary landfill and thickening-conditioning-dewatering-drying-sintering-building materials), and a contextual assessment of major influencing indicators in Bujumbura through a review of priorities defined in the country National Development Plan 2018-2027 and other relevant reports from the government and different local and international organizations, selected five key factors such as energy recovery, local policies and priorities, weather conditions, environmental impact rate, and capital investment, and analyzed which routes are more adapted for this city. Thus, an assessment matrix for suitability of each of the seven routes to each factor was developed to summarize the advantages and disadvantages for each scenario. The analysis results demonstrated that the financial capacity excludes incineration process. Energy recovery-oriented routes are likely to be particularly attractive due to their potential of producing electricity which is scarce in this city. The treatment should apply drying before disposal, a cost-free process using natural drying to reduce the cost and eventual environmental impact during sludge transportation to the disposal site. Landfilling is preferable over land application, to prevent the potential risk posed by the geographic position and topographic condition of the city. The study concluded that a route using anaerobic digestion, drying and landfilling would be a good choice for the area studied.