V2I9P7

Experimental Gasification of Biomass Pellets: Analysis of Syngas Production and Simulation Validation

Usiohen Iziegbe^1*, Anthony Chijioke Adingwupu²

Abstract

This study explores the potential of agro-waste as a renewable biomass source for syngas production with a high content of hydrogen. The experimental evaluation focused on various biomass feedstocks, including cassava peels, cocoa pods, and plantain peels, using gasification and pyrolysis techniques. Notably, cocoa pods exhibited high calorific and volatile matter content, indicating strong energy conversion potential. The research employed Aspen Plus modeling to simulate hydrogen production at different equivalence ratios (ER: 0.1 to 0.55), steam-air and steam as gasifying agents, and varying steam-to-air ratio (SAR: 0.1 to 1.0). Chemical looping reforming (CLR) was modeled using Fe2O3, CuFe2O4, and CuO/CuAl2O4 as oxygen carriers, assessing their impact on syngas H2 enrichment. The Experimental gasification results revealed that the optimal performance occurred at an ER of 0.35. Under this condition, H2 and CO concentrations were maximum, with cocoa pod skin pellet achieving the highest H2 of 7.94% and CO (27.22%), low heat value LHV of 4.1684MJ/kg, and CGE of 61.8765%. The Aspen Plus gasification model showed strong agreement with experimental data, accurately predicting syngas composition, H2, and cold gas efficiency CGE. Steam and steam-air mixtures significantly enhanced hydrogen yield compared to air as a gasifying agent, with optimal gasification performance observed at an ER of 0.35 achieving the highest CGE and LHV of 79.35% and 7.94MJ/kg respectively at SAR of 0.6 for cocoa pod skin pellet. CLR with all the oxygen carriers enhanced hydrogen concentrations further with CuO/CuAl2O4 proving to be the most effective oxygen carrier upgrading the H2 composition in the syngas to 49.78% for cassava peel pellet at SBR of 0.6, 46.04% for cocoa pod skin pellet at SBR of 0.6 and 46.23% for plantain peel pellet at 0.6 SAR with their corresponding LHV of 19.03MJ/kg, 17.81MJ/kg, and 17.9MJ/kg respectively. Findings revealed variable hydrogen yields and energy outputs across the feedstock types, highlighting the viability of utilizing local agro-waste for renewable energy applications and contributing to sustainable development initiatives in the production of  Syngas.

Keywords:

Syngas, Gasification, Agro-waste, equivalence ratios