A process for the manufacture of a useful product from carbonaceous feedstock of fluctuating compositional characteristics, comprising the steps of: continuously providing the carbonaceous feedstock of fluctuating compositional characteristics to a gasification zone; gasifying the carbonaceous feedstock in the gasification zone to obtain raw synthesis gas; recovering at least part of the raw synthesis gas from the gasification zone and supplying at least part of the recovered raw synthesis gas to a partial oxidation zone; equilibrating the H.sub.2:CO ratio of the raw synthesis gas in the partial oxidation zone to obtain equilibrated synthesis gas; recovering at least part of the equilibrated synthesis gas from the partial oxidation zone and treating the gas to remove impurities and generate a fine synthesis gas; and converting the optionally adjusted fine synthesis gas into the useful product in a further chemical reaction requiring a usage ratio.

Process for manufacturing a hydrogen-containing synthesis gas from a natural gas feedstock, comprising the conversion of said natural gas into a raw product gas and purification of said product gas, the process having a heat input provided by combustion of a fuel; said process comprises a step of conversion of a carbonaceous feedstock, and at least a portion of said fuel is a gaseous fuel obtained by said step of conversion of said carbonaceous feedstock, and the Wobbe Index of said fuel is increased by a step of carbon dioxide removal or methanation.

The invention relates to a process for the combined production of hydrogen and carbon dioxide from a hydrocarbon mixture, in which the residual gas of a PSA H.sub.2 (12) is separated by permeation in order to reduce the hydrocarbon content thereof and the hydrocarbon-purified gas is separated at a low temperature to produce a carbon dioxide-rich liquid (22).

Methods and systems for producing carbon-negative hydrogen and renewable natural gas from biomass are included herein. In an embodiment, the method may include gasifying biomass in a gasification unit to form a first stream comprising syngas. The syngas may include methane, hydrogen, carbon dioxide, carbon monoxide, ethylene, and water. The method may also include reacting the carbon monoxide with water in the presence of a catalyst to form a second stream. The second stream may include a greater hydrogen concentration than the first stream. The method may further include separating at least a portion of the second stream to form a hydrogen stream and a natural gas stream. The hydrogen stream may have a greater concentration of hydrogen than the second stream. The natural gas stream may have a greater concentration of methane than the second stream.

A plant complex may include a unit that produces CO.sub.2-containing gases, a gas conducting system for CO.sub.2-containing gases, a gas/liquid separation system, a reformer that is connected to the gas conducting system and where the CO.sub.2-containing gas reacts with H.sub.2 and/or hydrocarbons to give a CO— and H.sub.2-containing synthesis gas mixture. The reformer is connected to a reactor for producing higher alcohols in which the synthesis gas mixture reacts with H.sub.2 to give a gas/liquid mixture containing higher alcohols. For separating off the alcohols of the gas/liquid mixture, the gas/liquid separation system is connected to the reactor for producing higher alcohols.

A method for decreasing the SFFC of a steam reforming plant, including establishing a base operating mode. Then modifying the base operating mode by introducing the shift gas stream into a solvent based, non-cryogenic separator prior to introduction into the pressure swing adsorption and introducing the compressed hydrogen depleted off-gas stream in a membrane separation unit, wherein the membrane is configured to produce the hydrogen enriched permeate stream at a suitable pressure to allow the hydrogen enriched permeate stream to be combined with carbon dioxide lean shift gas stream, prior to introduction into the pressure swing adsorption unit without requiring additional compression. Thereby establishing a modified operating mode. Wherein said pressure swing adsorption unit has a modified overall hydrogen recovery. Wherein said modified operating mode has a modified hydrogen production, a modified hydrogen production unit firing duty, a modified SCO2e, and a modified SFFC.

A method for decreasing the SFFC of a steam reforming plant, including establishing a base operating mode. Then modifying the base operating mode by introducing the shift gas stream into a solvent based, non-cryogenic separator prior to introduction into the pressure swing adsorption and introducing the compressed hydrogen depleted off-gas stream in a membrane separation unit, wherein the membrane is configured to produce the hydrogen enriched permeate stream at a suitable pressure to allow the hydrogen enriched permeate stream to be combined with carbon dioxide lean shift gas stream, prior to introduction into the pressure swing adsorption unit without requiring additional compression. Thereby establishing a modified operating mode. Wherein said pressure swing adsorption unit has a modified overall hydrogen recovery. Wherein said modified operating mode has a modified hydrogen production, a modified hydrogen production unit firing duty, a modified SCO2e, and a modified SFFC.

A fuel reforming apparatus includes a pre-reformer that converts a fuel gas to methane by bringing the fuel gas into a reaction with water, a reformer that generates a mixture gas including hydrogen by bringing the fuel gas pre-reformed by the pre-reformer into a reaction with the water, a reformer burner that supplies heat to the reformer, and an exhaust gas supply line that causes an exhaust gas discharged from the reformer burner to be supplied to the pre-reformer as a heat source for the reaction of the pre-reformer.

Disclosed herein is a method for making hydrogen with carbon sequestration. The method may comprise using a biomass hydroconverter product to fuel a steam reformer that converts a hydrocarbon fuel stream into a gas mixture that contains at least hydrogen and carbon dioxide. The gas stream is separated to form a hydrogen-enriched gas stream and at least one hydrogen-depleted stream. The hydrogen-depleted stream may be stored or further processed to sequester the carbon contained therein. Additionally, or alternatively, the solid residue from the biomass hydroconverter also may be stored for further sequester carbon generated by the method.

A process and apparatus for producing syngas from low grade coal and from a biomass wherein the process includes (i) gasification of a mixture of low grade coal and biomass, (ii) reforming the gasified mixture, and (iii) removing CO.sub.2 from the gasified and reformed syngas mixture.