A carbonaceous fuel gasification system for a supercritical CO.sub.2 power cycle system includes a micronized char preparation system comprising a devolatilizer that receives solid carbonaceous fuel, hydrogen, oxygen, and fluidizing steam and produces micronized char, steam, hydrogen, and volatiles. An indirect gasifier includes a vessel comprising a gasification chamber that receives the micronized char, a conveying gas, and steam where the gasification chamber provides syngas, ash, and steam. A combustion chamber receives syngas and an oxidant and burns the mixture of syngas with the oxidant to provide heat for gasification and for heating incoming flows, thereby generating steam and CO.sub.2. The heat for gasification is transferred from the combustion chamber to the gasification chamber by circulating refractory sand. A syngas cooler cools the syngas and generates steam and provides to a supercritical CO.sub.2 power cycle system that performs a supercritical CO.sub.2 power cycle for generating power.

Embodiments described herein generally relate to a composite carbonate utilized as a catalyst in coal gasification processes. Methods described herein also include suitable processing conditions for performing coal gasification with the composite catalyst. In certain embodiments the composite catalyst may comprise an alkali carbonate and a transition metal carbonate, for example, an FeCO.sub.3Na.sub.2CO.sub.3 catalyst. An FeCO.sub.3Na.sub.2CO.sub.3 catalyst, compared to raw coal, may increase the carbon conversion rate by about two times within the 700 C.-800 C. range due to its ability to reduce the activation energy of gasification by about 30-40%. Compared to pure sodium and pure iron catalysts, the composite catalyst may increase the yields of desired products H.sub.2 and CO at 800 C. by 14.8% and 40.2%, respectively.

A carbonaceous fuel gasification system for a supercritical CO.sub.2 power cycle system includes a micronized char preparation system comprising a devolatilizer that receives solid carbonaceous fuel, hydrogen, oxygen, and fluidizing steam and produces micronized char, steam, hydrogen, and volatiles. An indirect gasifier includes a vessel comprising a gasification chamber that receives the micronized char, a conveying gas, and steam where the gasification chamber provides syngas, ash, and steam. A combustion chamber receives syngas and an oxidant and burns the mixture of syngas with the oxidant to provide heat for gasification and for heating incoming flows, thereby generating steam and CO.sub.2. The heat for gasification is transferred from the combustion chamber to the gasification chamber by circulating refractory sand. A syngas cooler cools the syngas and generates steam and provides to a supercritical CO.sub.2 power cycle system that performs a supercritical CO.sub.2 power cycle for generating power.

A carbonaceous fuel gasification system for a supercritical CO.sub.2 power cycle system includes a micronized char preparation system comprising a devolatilizer that receives solid carbonaceous fuel, hydrogen, oxygen, and fluidizing steam and produces micronized char, steam, hydrogen, and volatiles. An indirect gasifier includes a vessel comprising a gasification chamber that receives the micronized char, a conveying gas, and steam where the gasification chamber provides syngas, ash, and steam. A combustion chamber receives syngas and an oxidant and burns the mixture of syngas with the oxidant to provide heat for gasification and for heating incoming flows, thereby generating steam and CO.sub.2. The heat for gasification is transferred from the combustion chamber to the gasification chamber by circulating refractory sand. A syngas cooler cools the syngas and generates steam and provides to a supercritical CO.sub.2 power cycle system that performs a supercritical CO.sub.2 power cycle for generating power.

A bio-multi-reactor hydrogen generation method using a bio-multi-reactor hydrogen generation system including a plurality of carbonization-water gasification furnaces and a plurality of heating furnaces arranged alternately side by side includes: arranging solid combustibles in each carbonization-water gasification furnace; dry distilling the solid combustibles by heating from each heating furnace adjacent to each carbonization-water gasification furnace; gasifying carbide obtained by dry distillation within each carbonization-water gasification furnace by supplying steam to the carbide to cause a water gasification reaction to take place; and maintaining each heating furnace at a temperature for dry distilling the solid combustibles in each carbonization-water gasification furnace by collecting a combustible gas generated in dry distillation of the solid combustibles in each carbonization-water gasification furnace in a tank and supplying the combustible gas to each heating furnace for combustion.

A system for gasification of a carbonaceous material and recycling char or solids from a gasifier is disclosed. The recycling system may include a standpipe that receives a solids stream from a separator, the standpipe generating a pressure differential across a bed of accumulated char, thereby producing a bottoms stream having a greater pressure than the inlet solids stream. The recycling system may also include a holding vessel that receives the bottoms stream and a fluidized-bed distribution vessel that receives char from the holding vessel and is configured to provide a continuous and precise flow of recycled char to the gasification reactor.

A method of producing syngas wherein a carbonaceous feedstock is exposed to a plasma arc generated by a DC supply in a dry-steam environment.

A bio-multi-reactor hydrogen generation method using a bio-multi-reactor hydrogen generation system including a plurality of carbonization-water gasification furnaces and a plurality of heating furnaces arranged alternately side by side includes: arranging solid combustibles in each carbonization-water gasification furnace; dry distilling the solid combustibles by heating from each heating furnace adjacent to each carbonization-water gasification furnace; gasifying carbide obtained by dry distillation within each carbonization-water gasification furnace by supplying steam to the carbide to cause a water gasification reaction to take place; and maintaining each heating furnace at a temperature for dry distilling the solid combustibles in each carbonization-water gasification furnace by collecting a combustible gas generated in dry distillation of the solid combustibles in each carbonization-water gasification furnace in a tank and supplying the combustible gas to each heating furnace for combustion.

The invention is directed to a burner for the gasification of a solid fuel, comprising a burner front having an opening for discharging a solid fuel, wherein the opening for discharging the solid fuel is fluidly connected to a central passage way and wherein the central passage way has a downstream part wherein the diameter of the passage way increases over a first length and subsequently decreases over a second length terminating at the burner front and wherein inside the downstream part of the central passage way a hollow member is positioned, and wherein the hollow member has an internal increasing diameter and inner decreasing diameter aligned with the increasing and decreasing diameter of the hollow member and wherein the connecting conduits have a discharge opening positioned in the diverging part of the hollow member.

A carbonaceous fuel gasification system for a supercritical CO.sub.2 power cycle system includes a micronized char preparation system comprising a devolatilizer that receives solid carbonaceous fuel, hydrogen, oxygen, and fluidizing steam and produces micronized char, steam, hydrogen, and volatiles. An indirect gasifier includes a vessel comprising a gasification chamber that receives the micronized char, a conveying gas, and steam where the gasification chamber provides syngas, ash, and steam. A combustion chamber receives syngas and an oxidant and burns the mixture of syngas with the oxidant to provide heat for gasification and for heating incoming flows, thereby generating steam and CO.sub.2. The heat for gasification is transferred from the combustion chamber to the gasification chamber by circulating refractory sand. A syngas cooler cools the syngas and generates steam and provides to a supercritical CO.sub.2 power cycle system that performs a supercritical CO.sub.2 power cycle for generating power.