Patent ID: 7951212

Claim:
A method for the production of synthesis gas from biomass without subjecting the biomass to an initial drying operation, the method comprising the steps of: (a) introducing a combustible gas and air as an oxygen source and combusting the combustible gas in a combustion chamber to form hot flue gasses, (b) passing said flue gasses through heat storing means so as to heat said heat storing means to an elevated temperature, (c) retaining the flue gasses for initial use as a hot gaseous medium, (d) transporting the hot gaseous medium to a reactor containing biomass that has not been subjected to an initial drying operation, (e) heating the biomass to an elevated temperature with the hot gaseous medium to form synthesis gas, (f) transporting the hot gaseous medium from the reactor to an additional reactor containing additional biomass, (g) heating additional biomass in the additional reactor to an elevated temperature with the hot gaseous medium to form additional synthesis gas, (h) recycling the synthesis gas to the heat storing means to heat said synthesis gas, (i) withdrawing at least part of the synthesis gas formed, (j) recirculating the rest of the synthesis gas in form of the hot gaseous medium to the reactor, thereby continuing the production of synthesis gas through concurrent execution of steps (e)-(i), and (k) periodically reversing the direction of flow between the reactor and the additional reactor.