A second look at fast pyrolysis of biomass - the RTI process

Over the past two decades a great deal of experimental work as been carried out on the development of fast pyrolysis processes, particularly for biomass and for lignocellulosic waste materials. High yields of an organic liquid product (50-70%) are typical of atmospheric pressure short contact time pyrolysis of such feedstocks. This liquid product has been shown to be usable both as an alternative liquid fuel, and as a chemical feedstock because of its content of significant concentrations of potentially useful organic chemicals. The characteristics of the more important fast pyrolysis processes are reviewed, and the advantages and problems existing with present pyrolysis reactors are discussed, with the emphasis on bubbling fluidized bed systems. Experience with the process has led us to a somewhat different view of the optimal conditions for fast pyrolysis, and has resulted in the recent development of a new fluid bed process-the RTI Process. Characteristics of the RTI process are described and its advantages over existing fast pyrolysis technologies summarized. (C) 1999 Elsevier Science B.V. All rights reserved.