Disclosed embodiments provide a system and method for producing hydrocarbons from biomass. Certain embodiments of the method are particularly useful for producing substitute natural gas from forestry residues. Certain disclosed embodiments of the method convert a biomass feedstock into a product hydrocarbon by hydropyrolysis. Catalytic conversion of the resulting pyrolysis gas to the product hydrocarbon and carbon dioxide occurs in the presence of hydrogen and steam over a CO.sub.2 sorbent with simultaneous generation of the required hydrogen by reaction with steam. A gas separator purifies product methane, while forcing recycle of internally generated hydrogen to obtain high conversion of the biomass feedstock to the desired hydrocarbon product. While methane is a preferred hydrocarbon product, liquid hydrocarbon products also can be delivered.

The present disclosure relates to a power production system that is adapted to achieve high efficiency power production with carbon capture when using a solid or liquid hydrocarbon or carbonaceous fuel. More particularly, the solid or liquid fuel first is partially oxidized in a partial oxidation reactor that is configured to provide an output stream that is enriched in methane content. The resulting partially oxidized stream can be cooled, filtered, additionally cooled, and then directed to a combustor of a power production system as the combustion fuel. The partially oxidized stream is combined with a compressed recycle CO.sub.2 stream and oxygen. The combustion stream is expanded across a turbine to produce power and passed through a recuperator heat exchanger. The recycle CO.sub.2 stream is compressed and passed through the recuperator heat exchanger and optionally the POX heat exchanger in a manner useful to provide increased efficiency to the combined systems.

A waste treatment, pyrolysis and gasification and concerns an apparatus for syngas bio-methanation include a unit for pyrolysis/gasification receiving organic material, the unit for pyrolysis/gasification generating syngas, comprising at least one membrane reactor inside a liquid bath comprising at least one bacteria population, the membrane reactor comprising at least one hollow fiber in contact with the liquid bath, around which a biofilm is formed and into which the syngas from the unit for pyrolysis/gasification flows, so as to convert the syngas into methane. A method for bio-methanation of syngas comprising a step of providing syngas from a unit for pyrolysis/gasification to a membrane reactor inside a liquid bath comprising at least one suitable bacteria population, the membrane reactor comprising at least one hollow fiber in contact with the liquid bath, around which a biofilm is formed and into which the output syngas of the unit for pyrolysis flows, so as to convert the syngas into methane.

Aspects of the invention relate to improvements in the flexibility with which oxygen and hydrogen, for example from electrolysis, may be supplied to processes having both gasification and methanation steps, as well as improvements in how such processes may be operated in response to variations in carbonaceous feeds. Offsets, between the ideal quantity of hydrogen and the quantity available from a given source may be compensated for by adjusting one or more operations of the process, and in particular such operation(s) that ultimately impact the quantity of CO and/or CO.sub.2 available downstream of the gasifier for conversion to methane in an RNG product stream.

A carbonaceous fuel gasification system for all-steam gasification with carbon capture includes a micronized char preparation system comprising a devolatilizer that receives solid carbonaceous fuel, hydrogen, oxygen, and fluidizing steam and produces micronized char, steam, volatiles, hydrogen, and volatiles at outlets. An indirect gasifier includes a vessel comprising a gasification chamber that receives the micronized char, a conveying fluid, and steam. The gasification chamber produces syngas, ash, and steam at one or more outlets. A combustion chamber receives a mixture of hydrogen and oxidant and burns the mixture of hydrogen and oxidant to provide heat for gasification and for heating incoming flows, thereby generating steam and nitrogen. The heat for gasification is transferred from the combustion chamber to the gasification chamber by circulating refractory sand. The system of the present teaching produces nitrogen free high hydrogen syngas for applications such as IGCC with CCS, CTL, and Polygeneration plants.

Methods and systems for processing construction and demolition (C&D) materials to produce a product gas stream and/or electricity are disclosed herein. In some embodiments, the method comprises pre-processing C&D materials to produce a C&D feed, and processing the C&D feed to produce syngas. The C&D feed can comprise untreated wood, treated wood, paper and cardboard, yard waste, plastic, rubber, and/or foam. Processing the C&D feed can comprise gasifying the C&D feed, steam, and oxygen in a gasifier at a temperature of no more than 950 C. and/or a pressure of no more than 200 psi to produce syngas.

Certain exemplary embodiments can provide a system, machine, device, manufacture, circuit, composition of matter, and/or user interface adapted for and/or resulting from, and/or a method and/or machine-readable medium comprising machine-implementable instructions for, activities that can include and/or relate to, converting biomass to synthetic hydrocarbons using a biomass thermal decomposer and/or a hydrocarbon synthesizer.

A two-stage syngas production method to produce a final product gas from a carbonaceous material includes producing a first product gas in a first reactor, separating char from the first product gas to produce separated char and char-depleted product gas, and separately reacting the separated char and the char-depleted product gas with an oxygen-containing gas in a second reactor to produce a final product gas. The separated char is introduced into the second reactor above the char-depleted product gas. The solids separation device may include serially connected cyclones, and the separated char may be entrained in a motive fluid in an eductor to produce a char and motive fluid mixture prior to being transferred to the second reactor. A biorefinery method produces a purified product from the final product gas.

The present invention provides a process for preparing higher-value products from carbonaceous feedstocks. The process includes converting carbonaceous feedstock in a hydromethanation reactor to a methane-enriched raw product stream, converting the methane-enriched raw product stream to a methanol synthesis feed gas, then converting the methanol synthesis feed gas to higher-value products such as methanol and dimethyl ether.

A carbonaceous fuel gasification system for all-steam gasification with carbon capture includes a micronized char preparation system comprising a devolatilizer that receives solid carbonaceous fuel, hydrogen, oxygen, and fluidizing steam and produces micronized char, steam, volatiles, hydrogen, and volatiles at outlets. An indirect gasifier includes a vessel comprising a gasification chamber that receives the micronized char, a conveying fluid, and steam. The gasification chamber produces syngas, ash, and steam at one or more outlets. A combustion chamber receives a mixture of hydrogen and oxidant and burns the mixture of hydrogen and oxidant to provide heat for gasification and for heating incoming flows, thereby generating steam and nitrogen. The heat for gasification is transferred from the combustion chamber to the gasification chamber by circulating refractory sand. The system of the present teaching produces nitrogen free high hydrogen syngas for applications such as IGCC with CCS, CTL, and Polygeneration plants.