Performance prediction of waste polyethylene gasification using CO₂ in a bubbling fluidized bed: A modelling study

Gasification of carbonaceous materials using CO₂ from flue gases is an effective and economic means of waste recycling and environmental CO₂ mitigation system. The paper presents investigation on conversion of plastics, such as (poly) ethylene, into valuable gaseous products, primarily Syngas or synthesis gas using CO₂ as a gasifying agent instead of conventional steam. Typically, gasification is carried out in a fluidized bed reactor followed by sequential separation of syngas from tar and other undesired gaseous products. In this research work, the effect of operating conditions of the fluidized bed reactor on carbon conversion and H₂/CO mole ratio was examined. For this purpose, a process model of CO₂ gasification of waste plastics using fluidized bed reactor was developed in ASPEN PLUS^®. Sensitivity analysis concluded that parameters like CO₂ - feed ratio, residence time, and gasification temperature serve to control the yield and quality of syngas.