Thermodynamic equilibrium investigation to operational capabilities and process tolerance of plasma gasification for various feedstock

A thermodynamic equilibrium model is employed to study the capability of plasma gasification in waste to-value concepts. In difference to waste-to-energy concepts, not the caloric value of the product stream, but the achievable total amount of syngas as also the H-2 to CO ratio is focused on. Within the study the impact of the feedstock composition, use of gasification agent as also process temperature up to 1800 K is quantified. In the comparison of equilibrium modelled compositions with experimental compositions, it is exposed that compositions obtained by plasma gasification are in high agreement with the ideal equilibrium composition, unlike conventional gasification. It is shown, that above 1400 K a temperature invariant product composition can be achieved for a given feedstock, giving rise to high process tolerance for the high temperature plasma process. Additionally, the possibility to react on changes in feedstock composition and to tune the product gas composition through the flexible use of gasification agent is shown. Furthermore, a way to visualize an operational window of the gasification process is presented. Therefore, constraints set for the syngas ratio and amount as well as the solid carbon content are added based on the equilibrium calculation as borderlines to the van Krevelen plot. (c) 2021 Elsevier Ltd. All rights reserved.