Environmental Sustainability of Biohydrogen Production from Municipal Wastewater and Food Waste by Life Cycle Assessment

The environmental sustainability of biohydrogen production from municipal wastewater and food waste (FW) was evaluated by a life cycle assessment (LCA). Three scenarios with solid enzymes (Scenario 1), with commercial enzymes (Scenario 2), and without enzyme hydrolysis (Scenario 3) pretreatments were conducted for comparison. It was found that Scenario 1 was the most sustainable biohydrogen production scenario, with the lowest environmental impact. Moreover, the operating electricity and chemical usage were the key drivers to the environmental profile of Scenario 1 and Scenario 2, while the main contributors were chemical usage and infrastructure construction for Scenario 3. A significant positive influence on the environmental sustainability could be achieved from the improvement of biohydrogen yield, chemical usage, electricity conservation, and plant location. The obtained results could provide strong evidence of sustainable biohydrogen production from an environmental perspective. It was expected that this work would contribute to the establishment of a circular economy of resource recycling from waste.