Co-gasification of biomass and plastic waste for green and blue hydrogen Production: Novel process development, economic, exergy, advanced exergy, and exergoeconomics analysis

Abstract

A novel co-gasification process for biomass and plastic waste has been proposed to produce the blue and green hydrogen. For process feasibility, an Aspen Plus simulation model has been developed, and a sustainability analysis is being conducted, focusing on economic viability, exergy, advanced exergy considerations, and exergoeconomics evaluations. The current process has demonstrated economic sustainability, as evidenced by an internal rate of return (IRR) of 8 % at a process efficiency level of 70 %. The process with a waste capacity of 20 tons per hour has the potential to produce approximately 1079 kW-hours of electric power. The surplus electricity, exceeding the process requirements is utilized for green hydrogen production through an alkaline electrolysis cell (AEC). This surplus electricity has the potential to produce around 213.5 kg/day of hydrogen. The exergy analysis of this model highlights that the gasifier component exhibits the lowest exergy efficiency, resulting in the highest exergy loss, around 40 %. Furthermore, advanced exergy analysis identifies both the steam turbine and gasifier as primary sources of exergy destruction, with associated exergoeconomics costs of around $6,561.3 and $6,541.9 per hour, respectively. Consequently, improving the gasifier and steam turbine performance can enhance the overall sustainability of the process.