Prioritizing novel wastewater-to-hydrogen production technologies based on different decision-making approaches

With the increasing population, the amount of wastewater that needs to be managed is also increasing. Population growth also increases energy demand. While treating wastewater containing organic matter and water, hydrogen energy can be produced at the same time. In this study, microbial fuel cells, dark fermentation, supercritical water gasification, and photobioreactors that produce hydrogen from wastewater have been evaluated and prioritized for the first time in terms of benefit, opportunity, cost, and risk criteria. The analytic hierarchy process (AHP) technique and benefit, opportunity, cost, and risk (BOCR) model have been used to achieve this aim. In addition, a sensitivity analysis was performed to determine critical criteria for prioritizing technologies. With the analytic hierarchy process technique, it was determined that the criterion with the highest priority was benefit (53%), while the sub-criterion with the highest priority was technological development (33%) followed by operating cost (15%) and compliance with sustainability (12%). Supercritical water gasification technology was found to be the top priority with the AHP technique. In the BOCR model, dark fermentation was determined to be the highest priority technology. In the sensitivity analysis, changes in the weights of the opportunity and cost criteria showed that these criteria were critical. The results obtained show that dark fermentation, which is a technology close to the development, is preferred in the first rank because it has less risk and can produce a high rate of hydrogen. This study could spur more R&D work for researchers to industrialize this technology. It can also give an idea for different studies to researchers. Graphic abstract