Abstract: A method for the gasification of solid fuel to produce combustible effluent, comprising the steps of: partially oxidizing a biomass fuel in a first oxidation zone to produce char; reducing the char in a reduction zone to form ash; further oxidizing any char residue ash in a second oxidation zone; and extracting the combustible effluent produced in the above steps, by a discharge pipe wherein in the first oxidation zone the gas flow is in the same direction as fuel flow and in the second oxidation zone the gas flow is in the opposite direction to the fuel flow.

Abstract: A downdraft-updraft gasifier (1) and method for the gasification of biomass and waste to produce combustible effluent, the gasifier comprising: a fuel valve (22) for loading solid fuel (11) into a first oxidation zone (8); a first throat (2) defining the lower edge of the first oxidation zone (8); a second throat (4) defining the lower edge of a second oxidation zone (14); a reduction zone (5) linking the first oxidation zone (8) to the second oxidation zone (14) and a vortex discharge pipe (18) for the combustible effluent. The method includes steps of: partially oxidising a biomass fuel in the first oxidation zone (8) to produce char; reducing the char in the reduction zone (5) to form ash; further oxidising any char residue in the ash in the second oxidation zone (14); and extracting the combustible effluent produced in the above steps, by the discharge pipe (18).