Co-gasification of biomass and plastic wastes using a kinetic model in ASPEN plus

Abstract

The study developed a kinetic model for simulating the co-gasification of polyethylene (PE) blended with biomass (straw) using ASPEN plus (V.8.6). The model was validated against experimental results and showed good agreement. The study evaluated the influence of key parameters, such as PE content, temperature, and equivalence ratio (ER), on syngas composition, gas yield (GY), tar yield (TY), and char conversion efficiency (CCE). The addition of PE to straw increased H2 and CO content but decreased CCE. It also had a positive impact on gas production and a negative impact on tar conversion. With an increase in PE content from 0 to 30%, TY and GY increased from 10.1 to 20.04 g/Nm³ and from 0.73 to 0.91 Nm³/kg, respectively. An increase in gasifier temperature led to higher H₂ and CO content, resulting in increased GY. A higher gasifier temperature favored endothermic reactions, leading to increased char conversion and reduced tar release. An increase in ER favored tar and char conversion but decreased the formation of energetic components (H₂, CO, and CH₄). The model offers a practical approach for selecting an appropriate blend of biomass/PE for syngas production in targeted processes.