Analyzing Municipal Solid Waste Treatment Scenarios in Rapidly Urbanizing Cities in Developing Countries: The Case of Dar es Salaam, Tanzania

Abstract

Currently, large quantities of municipal solid waste (MSW) in many cities of the developing countries are being dumped in informal or formal but unregulated dumpsites that threaten the ecological environment and general public health. The situation in Dar es Salaam, Tanzania is of particular concern and is further challenged by a rapidly growing population and urbanization without adequate waste management systems. Current MSW treatment options have been selected based on the judgment and the experience of individuals with authority while underestimating the role of scientifically derived techniques. This study analyzes the most efficient waste treatment options, particularly scenarios with the lowest economic and environmental costs (EcC and EnC, respectively). It uses 12 years (2006–2017) of MSW management data and compares potential waste treatment options for the identified waste streams. A total of 108 different scenarios were designed, and a multi-criteria analysis method was applied to enable the identification of 11 scenarios with acceptable EcCs and EnCs. These formed an initial decision matrix of aggregation dominance that was then categorized into four groups, each represented by the most ideal point. Finally, the dominant scenario that formed the core for all considered options was found. It costs around $274,100 USD while saving about 1585 metric tons (MT) of CO2 emissions daily. This suggests that after all the MSW generated in the city is collected and segregated, organic waste should be composted whilst plastic, paper, glass, and ferrous metal should be recycled. After treatment, other waste will go to some form of landfill. Sustainable management of MSW in this city and others with similar conditions should consider particular local conditions and could use the methods and the findings of this study as a starting point.

A review on strategies to optimize metabolic stages of anaerobic digestion of municipal solid wastes towards enhanced resources recovery

“…Therefore, from Eqs. (11), (12), (13) and (14) the concentration of proportion of NH 3 , NH 4 + to TAN can be given by Eqs. (15) and (16).…”

“…In order to make decisions on technological selections to treat MSW, several factors must be considered including technical, economic, environmental, sociocultural, political, institutional, organizations and legal aspects of the local environment [101]. However analysis of all factors is often complex in developing countries due to the lack of data, and a few factors like the economic cost (EcC) and environmental cost (EnC) are often used as the basis of these analyses [13,102,103]. Table 6 depicts the average EcC and EnC costs (in USD) for treating 1 ton of MSW in developing countries for five treatment options as computed by various authors.…”

“…Kazuva and Zhang [13] investigated the MSW treatment scenarios with lowest EcC and EnC in rapid urban cities of developing countries using Dar es Salaam city in Tanzania as the case study. Using the ELECTRE Method, the best scenarios were found to be; composting for organic wastes, recycling for plastic, paper, glass and other waste to be landfilled.…”

“…In Dar es Salaam, Tanzania's largest city, about more than 5000 t of daily solid wastes are generated but only 40% of these wastes are collected by municipal councils in partnership with private sectors for disposal [13]. Such inadequate MSW disposal can affect human health through direct exposure or consumption of contaminated foods [14,15].…”

Thermal Characterisation Study of Two Disposable Diaper Brands

“…According to Arenas et al (2019:01), "waste management systems in developing economies are still insufficient and in some cases, cause environmental problems because waste tends to be unseparated and disposed of in open landfill sites." Landfilling, incineration and illegal dumping are the dominant methods of dealing with waste in many African countries (Achankeng, 2003, Williams, 2005, Zoeteman et al, 2010, Kazuva and Zhang, 2019, Kyere et al, 2019, and Oelofse and Nahman et al, 2019. A plethora of scholars (McKay, 2002, Hicks, 2007, Hristovski et al, 2007, Smyth et al, 2010, Topanou et al, 2011, Badgie et al, 2012, and Idowu, 2019 have cited the issue of poor waste characterisation as a major stumbling-block to waste management in Africa.…”