Sustainable solid waste management system using technology-enabled end-of-pipe strategies

Ever Increasing accumulation of solid waste, attributed to population growth and rapid urbanization, is a serious issue for all nations. This creates hindrance in implementing sustainable solid waste management systems (SWMS), which contribute to socio-economic-environmental-operational (SEEO) benefits for the nations and their citizens. Limited understanding of various solid waste management (SWM) practices, their operational sequence, and other system constraints pose numerous challenges for the concerned authorities and policy-makers. This paper provides a framework depicting three broad categories of strategies for managing solid waste: preventive, end-of-pipe (EOP), and environmental restoration. Among these, the research emphasizes on EOP strategies, being suitable alternative as per current requirements, to deal with massive amounts of generated waste. It further adopts Grey-DEMATEL approach to models the causal relationship among EOP strategies to identify the most influential strategy, which influences other ones. The model suggests waste segregation to be the major enabler for other EOP strategies, as it has maximum overall significance value (R + C) between 1.18 and 1.41 and it is the only one with positive value in "net-effect" computation (R-C), compared to other strategies with negative (R-C) values. This would enable concerned authorities to understand and follow the sequence of actions. Finally, a comprehensive framework is proposed for effective, efficient, and sustainable methods of handling different types of solid waste using technology-enabled EOP strategies. A case study is performed to demonstrate the significance of waste segregation towards SEEO benefits. It indicates that technology-based solutions at decentralized depots and establishment of biogas plant in the vicinity of garbage collection point leads to reduction in transportation cost and energy saving in efficient manner. The ground level implementation of our research in an Indian city resulted in the reduction of daily vehicle requirement from 25 to 20 vehicles, leading to approx. 25% savings in overall transportation costs thereby cutting exchequer's bill by up to $ 2820/month. It also reveals that mechanized and decentralized solutions were not effective for inert waste, its disposal to landfill was more suited alternative.