Fuel Gas Production From Self-Sustaining Smouldering Combustion of Lignocellulosic Waste

Abstract

Smouldering combustion has shown to be an effective application for soil remediation and as a waste treatment method for solids with high moisture content. The experimental set-up of smouldering combustion reactors is similar to autothermal fixed-bed gasification, updraft reactor configuration. In this study, smouldering experiments were conducted using lignocellulosic agricultural waste. The moisture content of lignocellulosic biomass was varied between 10 % to 50 %. Air flux was varied between 1.8 and 7.4 cm/s. Experiments were also conducted with varying oxygen concentration in the airflow (3.6 – 21 %), addition of sand (4 and 8 g/g) and other lignocellulosic material (wood pellets, and residual berry plant). Fuel gas with maximum H2, CO, CH4, CO2 concentrations of 7.7, 32.6, 2.3, and 57.4 % (N2 free) respectively were obtained with 10 % moisture content and 7.4 cm/s air flux. The smouldering yielded 1.24 Nm3/kgfeed_dry of gas with calorific value of 1.82 MJ/Nm3 (HHV).