Thermochemical conversion of municipal solid waste into hydrogen : a life cycle thinking based evaluation

The combustion of fossil fuels for energy needs has been identified as the leading cause of rapidly rising greenhouse gas (GHG) emissions, ultimately contributing to global warming. Its adverse consequences and the depletion of fossil fuel reserves have prompted researchers worldwide to develop environment-friendly renewable energy sources. Hydrogen (H₂) has been identified as a fuel with immense potential to satisfy the need for environmentally benign energy sources. However, the primary H₂ production pathways currently realized at a commercial scale involve fossil fuel utilization, creating the need for methods with lower GHG emissions. Energy recovery as H₂ from various types of waste shows considerable promise in cleaner H₂ production and in diverting waste streams away from landfills and other costly treatment. Nonetheless, most waste-to-hydrogen (WTH) pathways are incipient and require significant efforts to be established as an indispensable element of the path towards sustainability. Also, the evaluation of these technologies should consider their technological, environmental, economic, and societal elements. Thus, this study aimed to introduce a methodical framework based on life cycle thinking for assessing the sustainability of WTH processes. Four thermochemical WTH processes using municipal solid waste (MSW) as feedstock are analyzed for their technological, environmental, economic, and social feasibility using chemical engineering simulations and life cycle environmental and economic assessments. Furthermore, multicriteria decision-making (MCDM) is incorporated into the assessment under four different decision-making settings to demonstrate the versatility of the WTH concept. A parametric analysis is also performed to evaluate the effect of volatile market conditions and processing capacities on the life cycle cost of waste-derived H₂. Moreover, the influence of several community characteristics and the potential of establishing waste-to-energy refineries for multigeneration have also been discussed. The novel contributions of this study to the evolving field of WTH would benefit decision-makers, investors, utility providers, researchers, policymakers, and consumers to assess the feasibility of WTH technologies and make informed decisions on the implementation of WTH conversion facilities.Applied Science, Faculty ofEngineering, School of (Okanagan)Graduat