Investigations on the Catalytic Activity of Bed Material Coating Regarding the Water-Gas-Shift Reaction and Steam Reforming of Model Compounds for Lighter and Heavier Hydrocarbons

An innovative process to produce synthesis gas from a solid feedstock is dual fluidbed (DFB) steam gasification of biomass. The principle of this technology is the separation of the fluidized bed into a gasification and a combustion zone. Bed material, nowadays olivine, is circulating, between them, which has two functions. Firstly, it acts as heat carrier from the combustion to the gasification zone. Secondly, it has the role of a catalyst regarding the reduction of hydrocarbons. In this work, the catalytic activity of different fresh and also used bed materials, such as olivine and silica sand was tested regarding their ability to enhance the water-gas-shift reaction and also reduce hydrocarbons. Calcite is known as active material in this respect and, therefore, used as reference substance. Experiments showed a correlation between the enhancement of the water-gas-shift reaction and the reduction of lighter and heavier hydrocarbons by steam reforming. Results show that as long as a bed material particle has built up a calcium-rich layer, satisfying conversion of carbon monoxide and the hydrocarbons can be achieved. As model substances for hydrocarbons ethane and toluene were used. These results are the basis for further research of catalytic characteristics of potential bed materials for the dual fluidized bed steam gasification of biomass.
Proceedings of the 23rd European Biomass Conference and Exhibition, 1-4 June 2015, Vienna, Austria, pp. 562-567