Method of producing liquid fuel from carbonaceous feedstock through gasification and recycling of downstream products

A method of producing a fuel from carbonaceous material, the method comprising:

• contacting the carbonaceous material with a particulate heat transfer material in one or more reactors;
• reacting the carbonaceous material with steam and oxygen in the presence of the particulate heat transfer material in the one or more reactors to yield a product comprising solids and product gas, wherein the product gas comprises carbon dioxide;
• removing a mixture comprising some of the particulate heat transfer material and some of the solids from at least one of the one or more reactors;
• separating the particulate heat transfer material and the solids in the mixture in a classification chamber in the presence of a classifier gas to yield classified particulate heat transfer material for recycling and classified inert feedstock contaminant for draining, wherein said draining further comprises depressurizing the classification chamber;
• providing the classified particulate heat transfer material for recycling to at least one of the one or more reactors;
• cooling the product gas;
• scrubbing the product gas;
• compressing the product gas;
• and
• treating the product gas to yield the fuel.