Patent ID: 8192647

Claim:
A process for producing synthesis gas from biomass, comprising: (a) contacting said biomass with an oxidizing gas comprising oxygen and steam, wherein said oxygen is present in an amount effective to oxidize said biomass and to heat said biomass to a temperature of at least 500° C. and no greater than a maximum of 750° C.; (b) treating at least a portion of said oxidized biomass produced in step (a) with an oxidizing gas comprising oxygen and steam in a first stage to heat said oxidized biomass to a temperature which is at least 800° C. and does not exceed a maximum of 850° C.; (c) treating at least a portion of said oxidized biomass produced in step (b) with an oxidizing gas comprising oxygen and steam in a second stage to heat said oxidized biomass to a temperature which is at least 900° C. and does not exceed a maximum of 1,000° C., thereby producing synthesis gas; and (d) recovering said synthesis gas produced in step (c).