Thermal treatment of biomass

摘要

A biomass pyrolysis process is provided in which biomass feedstock is mixed with a heat carrier. The heat carrier at least partly comprises char. The ratio by weight of biomass to char is in the range 1:1 to 1:20. The process may be carried out by in a screw/auger pyrolysis reactor in which the solid feedstock components are conveyed along the reactor by a first screw. A second screw conveys at least a portion of the solid products of the biomass pyrolysis back to a heat transfer medium input port. Thus, the heat transfer medium includes char from the biomass pyrolysis.

主权项

1. A biomass pyrolysis process including the steps:
conveying by a first conveying means biomass feedstock and heat transfer medium from a biomass feedstock input port and heat transfer medium input ports through a pyrolysis zone of a biomass pyrolysis apparatus to produce at least solid and gaseous biomass pyrolysis products; and conveying by a second conveying means at least a portion of the solid products from an output port of the pyrolysis zone back to the heat transfer medium input port, wherein the second conveying means conveys at least a portion of the solid products through the biomass pyrolysis apparatus and is disposed in thermal contact with the first conveying means at the pyrolysis zone within the biomass pyrolysis apparatus, and wherein the first and second conveying means are located with respect to each other so that one of them surrounds at least part of the other or so that they are adjacent to each other.