This research develops a thermochemical simulation model for the co-gasification of lignocellulosic biomass, specifically a 50:50 blend of rice husk and oil palm fiber, using Aspen Plus. Based on a thermodynamic equilibrium approach, the model simulates the operation of a downdraft gasifier to evaluate the impact of key operational variables on syngas quality and process efficiency. The performance indicators analyzed include syngas composition, Lower Heating Value (LHV), Cold Gas Efficiency (CGE), and Carbon Conversion Efficiency (CCE). Following a successful validation against experimental data from the literature, a sensitivity analysis was conducted by varying the gasification temperature (600–1000 °C) and the equivalence ratio (ER) (0.1–0.6). The results demonstrate that increasing the temperature significantly enhances the molar fractions of H2 and CO, while an optimal ER of 0.15 maximizes the LHV and CGE. Specifically, the gas composition exhibited the highest sensitivity within the 600–800 °C range, where endothermic reactions are predominantly activated. This study provides a robust predictive framework for optimizing co-gasification processes, contributing valuable insights for the design of sustainable waste-to-energy systems.
Morales et al. (Mon,) studied this question.