Experimental evaluation of wood and grass pellets in a bubbling fluidized bed gasifier

Biomass gasification is an attractive technology capable of producing a versatile product gas that can be used for heat and power production as well as used as a feedstock for biofuels and higher-value chemicals synthesis. A fluidized bed gasifier is one of the better choices for an industrial scale operation. However, the specification and performance of different feedstocks must be characterized to use in a specific application with acceptable efficiency. In this article, the authors took two different feedstocks (i.e., wood and grass pellets) for the experimental characterization in a 20-kW pilot-scale bubbling fluidized bed gasifier. Equivalence ratio was varied between 0.1 to 0.2 for the grass pellets and 0.214 to 0.371 for the wood pellets. Frequent agglomerations were observed during the experiment with the grass pellets at a temperature of 800 degrees C and above. The carbon conversion for the gasification of grass pellets was observed to be lower compared to the gasification of wood pellets. Gasification of wood pellets gave a carbon conversion of around 60% at a temperature of around 850 degrees C. (c) 2023 The Author(s). Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Automated summary

Biomass gasification is a promising technology for producing versatile product gases, and the choice of a fluidized bed gasifier is suitable for large-scale industrial operations. Characterizing different feedstocks is crucial for achieving acceptable efficiency in specific applications. This study experimentally characterized two feedstocks (wood and grass pellets) using a 20-kW pilot-scale bubbling fluidized bed gasifier. The carbon conversion for grass pellets was lower compared to wood pellets, and frequent agglomerations were observed at temperatures above 800 degrees C. Wood pellet gasification achieved a carbon conversion of approximately 60% at around 850 degrees C.