Comprehensive examination and analysis of thermodynamics in a multi-generation hydrogen, heat, and power system based on plastic waste gasification integrated biogas -fueled chemical looping combustion

Plastic waste has captured considerable attention in gasification studies as it not only generates precious syngas rich in hydrogen but also aids in mitigating the environmental concerns linked to these substances. The proposed system employs the process of plastic waste gasification (PWG) to generate synthetic gas, which undergoes processing within multiple subsystems. Crucially, this ingenious system uses the liberated heat from the biogasfueled chemical looping combustion (CLC) to facilitate the efficient decomposition and gasification of the plastic waste, which the CLC holds great potential as a technology for capturing CO2 without any energy penalty. In the Aspen Plus software, a comprehensive simulation is conducted for the proposed system, with a focus on detailed modeling of CLC. Through this analysis, it is determined that the optimal operating condition for CLC occurs at a molar ratio of 2.6 between the oxygen carrier and biogas. Also, the results show that the overall thermal and exergy efficiencies of the CLC-PWG system are found to be 77.08% and 67.62%, respectively. Regarding exergy destruction distribution, it is noteworthy that the air reactor significantly contributes to the highest proportion, accounting for 35.3% of the total exergy destruction. Subsequently, the fuel reactor and gasifier also play significant roles, accounting for 13.6% and 13.1%, respectively. In addition, the proposed system has a power, heat and hydrogen production rate of 97 kW, 388 kW and 105.6 kg/hr, respectively. Moreover, the thermodynamic efficiencies increase through the elevation of the gasification reactor temperature and the mass ratio of steam to plastic waste.