Integrated Techno-Economic and Sustainability Assessment of Value-Added Products Generated from Biomass Gasification: An Energy-Water-Food Nexus Approach

The intrinsic dependency between energy-water-food (EWF) resources is becoming more obvious with the growing demand for these resources. As such, it is necessary to develop assessment tools that adequately quantify the interlinkages between EWF systems and the surrounding environment and identify synergies and trade-offs that may exist. Meanwhile, biomass can be regarded as a potential replacement capable of lowering ecological footprint and resource scarcity in a variety of applications. Gasification is a favored method for biomass valorization, where the produced gas mixture is used to run power plants and generate clean energy. Furthermore, it can also be utilized in chemical industries to replace natural gas in the generation of ammonia and methanol. Assessing the strategy of various biomass utilization represents a rich research subject that can be tackled from an EWF Nexus standpoint, enabling quantifying the biomass utilization implications on the EWF systems. The economic feasibility of using biomass gasification feedstock for poly-generation of various products is examined in this study. Aspen Plus software is used to simulate three alternative gasification processes to generate the best characteristics for each application route. Furthermore, a sustainability index is used to assess the impact of each application route on EWF systems and to support financial decisions. The simulation results are incorporated into a linear programming optimization model to determine the best biomass utilization approaches considering economic feasibility and resource preservation. The optimization results demonstrate that steam gasification with syngas end-use for methanol production (95%) and power production (5%) are the most feasible biomass utilization routes, with an overall collective objective function of 997%, net water generation of 4.39, net food of zero, and net energy production of 1.78 x 10-15.