Fluidized bed gasifier

Abstract From the Canadian patent

There are disclosed a process and a plant for gasifying biomass. The plant has a pressure vessel containing a hot fluidized sand bed. The bio-mass is pre-dried to a moisture content of from 10% to 35% by weight. A streamfree oxygen-containing gas is fed and distributed through, a grid system at the bottom of the hot sand bed to hold, the bed in a fluidized state and to form in its lower, portion, an oxygen-rich heat-forming combustion zone and, in its upper portion, a hydrogen-rich gas-forming pyrolysis zone. The pre-dried biomass is uninterruptedly fed in the pyrolysis zone at essentially the center of the hot fluidized bed, this center being determined when the sand bed stands at rest. …