METHOD AND SYSTEM FOR THE TORREFACTION OF LIGNOCELLULOSIC MATERIAL

摘要

A method for torrefaction of lignocellulosic biomass using a torrefaction reactor vessel (10, 70, 100) having stacked trays (42, 74, 102, 104), the method including; continuously feeding the biomass to an upper inlet (14) of the torrefaction reactor vessel such that the biomass material is deposited on an upper tray of a plurality of trays stacked vertically within the reactor; as the biomass moves across an upper surface of each of the trays, heating and drying the biomass material with a gas (18) injected into the vessel, wherein the gas is substantially non-oxidizing of the biomass, is under a pressure of at least 20 bar gauge and at a temperature of at least 200°C; cascading the biomass down through the trays (42, 74, 102, 104) by passing the biomass through an opening (46) in each of the trays to deposit the biomass on a lower tray; discharging torrefied biomass from a lower outlet (16, 81, 116) of the torrefaction reactor vessel, and circulating gas (30, 31, 24, 64, 76, 77, 78, 79) extracted from a lower elevation of the reactor vessel to an upper region (15) of the reactor vessel.