Energy efficient liquefaction of biomaterials by thermolysis

摘要

A thermolysis process for the production of volatiles for an external combustor (203) or liquefaction of biomass solids in which specific and previously unrecognized conditions are employed. The thermolysis is carried out in a single deep fluidized bed (211) of inert material operating at near atmospheric pressure, relatively low temperature, long solids and gas residence times and moderate heating rates. The distribution of the thermolysis products among solid (char) and gases under these conditions is unique. The product effluent can be either quenched to produce a high liquid yield in addition to a low char yield or the volatile effluent can be used in either the same combustor (203) or a second combustor (310) to produce heat energy a particularly high efficiency system. In using a quencher (403), the quenched liquid is of similar composition to those obtained by so called fast pyrolysis procees of the prior art. The specified conditions are such as to allow production of liquids in high yields in an energy efficient manner. The low severity of the conditions in comparison with previous approaches allows simplified process design and scale-up leading to lower capital and operating costs as well as easier control.