Biomass chemical looping gasification for syngas production using LD Slag as oxygen carrier in a 1.5 kWth unit

Biomass Chemical Looping Gasification (BCLG) is an autothermic gasification process that provides pure syngas for many applications, including liquid biofuels production. Finding low-cost materials that can be used in the process is a key issue, especially when they come from waste. In this sense, LD Slag is a by-product of the steel industry used as an oxygen carrier in Chemical Looping Combustion with good results. This work investigates the use of LD Slag as oxygen carrier in a continuous 1.5 kWth BCLG unit. The effect of the main operational variables (temperature, oxygen-to-fuel and steam-to-biomass ratios) and the use of CO2 instead of steam as gasification agent were analysed. LD slag allowed the process with high biomass conversions, X-b > 90%, carbon conversion efficiencies, eta(cc) > 90%, and syngas yields, Y approximate to 0.66 Nm(3)/kg of dry biomass, at conditions corresponding to autothermal operation. A lifetime of 300 h under reducing conditions was inferred and agglomeration problems were never detected. LD slag can be considered a suitable material for BCLG since it is possible to obtain high quality syngas at autothermal conditions from different types of biomass with low tar generation and CO2 emissions.

Automated summary

Biomass Chemical Looping Gasification using LD slag as an oxygen carrier can produce high quality syngas from various types of biomass under autothermal conditions, without agglomeration issues.