title: Life Cycle Sustainability Assessment (LCSA) of decentralized municipal food waste to compost process – a way forward to mitigate climate change
Creators: name: Ashraf, Azad Ibn
Publisher: name: University of Reading
Year: 2024

description: As a result of an increase in the global population, about 2.01 billion metric tons of municipal 
solid waste is produced worldwide of which about 33% remains unmanaged. The literature review
did not reveal any in-depth study to manage municipal solid waste (MSW) in a novel way such 
as a decentralized waste-to-composting approach using Life Cycle Sustainability Assessment 
(LCSA). Therefore, the main objective of this study was to use the comprehensive LCSA 
paradigm, for assessing the environmental, social, and economic impacts of MSW management 
using a decentralized facility. Each of the three LCSA components was assessed in Dhaka, 
Bangladesh. The Environmental Life Cycle Assessment (ELCA), Social Life Cycle Assessment 
(SLCA), and Life Cycle Costing (LCC) approaches were used. The study assessed and contrasted 
three alternative waste management procedures with a proposed waste-to-compost facility using 
a Photovoltaic (PV) solar panel-based automated waste-to-compost machine, including windrow 
composting at a decentralized site and two landfilling methods; sanitary and unsanitary. Open-LCA software was used to conduct ELCA for the four scenarios: windrow composting (S1), 
automated solar-powered composting machine (S2), and the current sanitary (S3) and unsanitary 
(S4) landfilling practices. The ELCAs were conducted for each environmental burden of ELCA 
analysis. One ton of municipal solid waste was used as a functional unit.
Compared to S3 (~2.12 million tons of CO2-eq) and S4 emissions, the total annual GWP100 from 
S1 (1.14 million tons CO2-eq) and S2 (411 kg CO2-eq) was significantly lower. S2 showed the 
lowest level of emissions for all categories when compared to the other three scenarios. There was 
a strong likelihood that utilizing an unsanitary landfill would affect the environment much more 
than it already has. 
In the SLCA study the result reveals that for an indicator score ranging from 0 (best performance) 
to 1 (bad performance), the workers obtained an average score of 0.5 for fair wages in the working 
conditions subcategory, compared to an average score of 0.3 for informal workers. In the final 
analysis, the social security subcategory received an average score of 0.9 from both workers which 
is significantly less than anticipated. 
When analyzing LCC, the estimated total cost of the decentralized windrow composting facility 
project was 2,944,404 USD. This figure is significantly more reasonable when compared to the 
expenses of landfilling and traditional composting methods: a $1,894,243 initial expenditure and 
an annual operating cost of 53,578 USD. The decentralized facility with an automated solar based
waste to compost machine was the most economical option since it had significantly fewer 
environmental costs than the other choices. Sanitary landfill had the highest total cost (37,885,978 
USD) and the proposed model of PV solar panel-based automated machine had the lowest total 
cost (139,252 USD). 
Finally, the goal of LCSA, which included ELCA, SLCA, and LCC, was to ascertain which waste 
management strategies were the most sustainable considering social, environmental, and 
economic considerations as well as if these strategies differed from one another. LCSA scores for 
the four distinct waste management scenarios were based on a 1 to 5 ranking scale. With a 
photovoltaic-powered composting system, the decentralized waste-to-compost facility achieved 
the highest LCSA score of 4.3. With 2.8, the windrow composting facility placed second, while 
the sanitary and unsanitary landfills were least desirable, with scores of 1.97 and 1.5, respectively. 
The significance of the study is that it provides novel insights on decision-making around waste 
management scenarios/options using LCSA analysis, as well as applying a novel, more structured 
framework (including the Analytic Hierarchy Process) to select between waste management 
options. In conclusion, the LCSA method provides a framework to consider and measure the larger 
life cycle impacts of systems throughout a range of criteria of sustainability. LCSA can act as a 
decision support tool by providing an overview of the sustainability performance of potential 
waste management processes. For optimal benefit, decision-makers need to consider the 
numerous trade-offs that this type of study uncovers as well as the varying goals of relevant 
stakeholders.