Gasification of Miscanthus x giganteus pellets in a fixed bed pilot-scale unit

Gasification of Miscanthus x giganteus (Mxgig), is highly promising due to the high efficiency of the process and the many advantageous properties of this crop. Pilot-scale, fixed bed gasification studies were performed utilizing this fuel at three temperatures (750, 850, and 950°C) to determine the process effects of temperature on gas quality and tar yields. Simple thermodynamic equilibrium modeling was successfully applied to the pilot-scale gasification process. The Mxgig crop performed well, with best process stability reached at temperatures of 800°C or higher. Average calorific values of the product gases were highest at around 850°C at 5.2 MJ·m−3. Tar yields gradually increased with increasing temperature and dropped after 900°C. The presented thermodynamic equilibrium model conformed well with experimental results, deviating little in terms of O2, CO2, H2, and CH4 and no more than 8.1% in the case of CO. This indicates that simple modeling methods can be utilized to predict gas compositions for the pilot-scale.