E. Henrich, F. Weirich
A new concept for the gasification of dry lignocellulosic biomass has been developed. Special attention was paid to the process compatibility with biomass feedstocks from agriculture, mainly straw, which have a higher ash, potassium and chlorine content and a lower ash softening point than wood. The first process step is a fast pyrolysis at atmospheric pressure, which produces much condensate and only little char and gas. Pyrolysis condensate and pulverized pyrolysis char are then mixed to a slurry, containing up to 90% of the initial biomass energy. In contrast to the loose-packed original biomass the dense slurries are easily pumped and stored in tanks. From a number of regional pyrolysis plants, the slurries can be transported by rail to a large central gasification facility. Thus, the economy of scale can make possible an efficient but more complex gasification and syngas utilization technology, to produce the most valuable products.