Advances in catalytic hot gas clean up and conditioning at pilot, scale with nickel based catalysts in fluidized bed biomass gasification

Gas from a fluidized bed biomass gasifier is cleaned of tars using a catalytic reactor with commercial steam reforming (nickel based) catalysts. The biomass gasifier used is an atmospheric and bubbling fluidized bed of 15 cm i.d. and 3.2 m high, with a feed rate of 10-15 kg biomass/h. Gasifying agents used have been air and steam-On mixtures. Calcined dolomites are used both in-bed and downstream from the gasifier. Commercial steam reforming catalysts from BASF AG, ICI-Katalko, Haldor Topsoe A/S and UCI have been used in a slip flow downstream from the gasifier. After an exhaustive testing of different steam reforming commercial catalysts, the 'best' catalyst for biomass gasification has been selected. Several tests have been made using this selected catalyst with its original size and shape and, definitely, it proved its high usefulness for tar destruction. Long-term experiments have been also made to study catalyst life.