Performance evaluation of biomass chemical looping gasification in a fluidized bed reactor using industrial waste as oxygen carrier

The study investigates biomass chemical looping gasification (BCLG) using nickel smelter slag as an oxygen carrier (OC). Key operating parameters, including reactor temperatures (800-900 degrees C), OC-to-biomass ratio (OCBR, 4:1-15:1), and steam as a gasification medium, were evaluated in a 5kWth fluidized bed reactor using pine forest residue. Performance metrics including gas composition and process efficiencies were assessed. OCs were characterized using XRD, BET and SEM-EDS analyses. Optimal performance was achieved at 850 degrees C, an OCBR (10:1) and a steam-to-biomass ratio (1.4). The gas composition was 38.87 vol% H2, 19.65 vol% CO, 34.48 vol% CO2, and 6.61 vol% CH4, with a product gas yield of 1.24Nm3/kg-biomass. Carbon conversion efficiency was 77.85 %, cold gas efficiency 58.70 %, and levelized cost of fuel was 0.15 <euro>/Nm3 for product gas and 4.55 <euro>/kg for H2.The results suggest that steam addition significantly enhanced char conversion, improving overall BCLG efficiency. Moreover, nickel smelter slag demonstrated stability, consistent reactivity, and limited sintering behavior.