Unraveling the sustainability aspects of coal extraction and use in Bangladesh using material flow analysis and life cycle assessment

Abstract

Bangladesh's metamorphosis into an export-based industrial economy from an agrarian one pushes its grid energy mix to lean towards a coal-dominated future which contradicts its Sustainable Development Goals (SDG) aspirations. Bangladesh needs local Life Cycle Inventory (LCI) databases to assist informed high-impact policymaking since product and process sustainability assessments are becoming inevitable for compliances. Bangladesh lacks an LCI database for coal mining and import which this study aimed to prepare. Besides, this study conducted both Material Flow Analysis (MFA) and Life Cycle Assessment (LCA) of coal to elucidate options for making imports and utilizations of coal more sustainable. The functional unit of the LCA was 1-MT (metric ton) energetic hard coal, the spatial system boundary was the international border of Bangladesh, and the temporal system boundary was the 2017 fiscal year. LCA used ILCD and ReCiPe 2006 impact assessment methods. The study used both primary and secondary data on mining, import, transportation, and sectoral use of coal. Overall, the environmental impacts of imported coal were higher than locally mined coal if the mining process at the source is considered. Coal consumption in Bangladesh mainly contributed to - Climate change (835 kg CO2 eq), causing 22% of the total environmental burden, followed by Human toxicity, cancer effects (18%); Acidification (16%); Human toxicity, non-cancer effects (13%) midpoint indicators. Coal sourcing scenario analysis indicated importing coal from Australia, South Africa, and Indonesia is the lower-impact options than importing from India. Surprisingly, MFA indicated 46% of the total input as hidden import flows, indicating the need for intensive investigation to evaluate hidden flows. MFA also indicated the need to reduce the reliance of brick kilns on coal besides assuring the cleanest coal-fired power plants. The results produced the baseline of impacts for mining, importing and using coal in Bangladesh as the country is poised to see a rapid increase in coal import, extraction and use. The hotspot analysis indicated options for coal mine management in Bangladesh to lower the environmental footprint of mining.