An energy conversion apparatus may include an engine assembly, such as a monolithic engine assembly. The engine assembly may include a first monolithic body segment and a plurality of second monolithic body segments directly coupled or directly couplable to the first monolithic body segment. The first monolithic body segment may define a combustion chamber and a recirculation pathway in fluid communication with the combustion chamber. The recirculation pathway may be configured to recirculate combustion gas through the combustion chamber. The plurality of second monolithic body segments may respectively define at least a portion of a piston chamber and a plurality of working-fluid pathways fluidly communicating with the piston chamber.

A combustible ice efficient combustion system comprises a combustible ice storage unit and a combustion unit, the front end of the furnace of the combustion unit is provided with a combustor, the rear end of the furnace of the combustion unit is connected with a flue gas main pipe, the combustor is provided with a first fuel gas inlet, a second fuel gas inlet, a combustion-supporting gas inlet and a flue gas outlet, the first fuel gas inlet is provided with a combustion nozzle, the combustion nozzle is provided with a first gas inlet, a second gas inlet and a mixed gas outlet, the first gas inlet is connected with the combustible ice storage unit through a high-pressure natural gas pipeline, the second gas inlet is connected with an air source, and the mixed gas outlet is connected with the first fuel gas inlet of the combustor.

A combustible ice efficient combustion system comprises a combustible ice storage unit and a combustion unit, the front end of the furnace of the combustion unit is provided with a combustor, the rear end of the furnace of the combustion unit is connected with a flue gas main pipe, the combustor is provided with a first fuel gas inlet, a second fuel gas inlet, a combustion-supporting gas inlet and a flue gas outlet, the first fuel gas inlet is provided with a combustion nozzle, the combustion nozzle is provided with a first gas inlet, a second gas inlet and a mixed gas outlet, the first gas inlet is connected with the combustible ice storage unit through a high-pressure natural gas pipeline, the second gas inlet is connected with an air source, and the mixed gas outlet is connected with the first fuel gas inlet of the combustor.

A method for transferring thermal energy to a separate endothermic process includes: (a) providing a carbon dioxide (CO.sub.2) stream and a carbonaceous fuel to a heater; (b) reacting the carbonaceous fuel in the heater to produce a heated stream; (c) transferring heat from the heated stream to the separate endothermic process; (d) separating the CO.sub.2 stream from the heated stream after (c); and (e) recycling the CO.sub.2 stream to the heater after (d).

A coal-fired power generation system may include a boiler outputting flue gas, a coal pulverizer associated with the boiler, and a heat exchanger. The heat exchanger may be configured to exchange heat from the flue gas to a primary air path and a secondary air path. The primary air path is coupled to the coal pulverizer, and the secondary air path is coupled to the boiler. The coal-fired power generation system may include a controllable air recirculation path coupled from an output of the primary air path to an input of the secondary air path.

A coal-fired power generation system may include a boiler outputting flue gas, a coal pulverizer associated with the boiler, and a heat exchanger. The heat exchanger may be configured to exchange heat from the flue gas to a primary air path and a secondary air path. The primary air path is coupled to the coal pulverizer, and the secondary air path is coupled to the boiler. The coal-fired power generation system may include a controllable air recirculation path coupled from an output of the primary air path to an input of the secondary air path.

A heating device, preferably for the combustion of biomass, in particular of pellets of biomass, in one aspect, includes a burner part and a heating part. The burner part includes a combustion chamber; a double-walled, internally hollow combustion-chamber wall, which has an upper opening leading above the combustion zone into the combustion chamber; a flue-gas duct which leads the flue gas downwards along the combustion chamber, wherein the flue-gas duct is followed by a heat-exchanger area including initially, a flat-tube flue-gas heat exchanger, then, a tertiary-air heat exchanger; a flue-gas ventilation stack, a radiant-heat exchanger located above the combustion chamber, a flue-gas flap at the upper end of the flue-gas duct, which, when open, connects the flue-gas duct to the stack. A flat-tube flue-gas heat exchanger of the heating part forms a heat-exchanger circuit with an exhaust-air heat exchanger with the same heat-transfer medium as the flat-tube flue-gas heat exchanger.

A boiler system is provided including: a boiler that burns fuel containing sulfur content, chlorine content, and water content to generate a combustion gas; a bagfilter that removes sulfur oxide; a denitration section that removes nitrogen oxide; a desulfurizing absorbent supply section that mixes a desulfurizing absorbent into the combustion gas on an upstream side of the bagfilter; and a reformer that mixes a denitrating reagent into the combustion gas on an upstream side of the denitration section, wherein the bagfilter performs dry desulfurization, and a temperature of the combustion gas passing through the bagfilter and flowing into the denitration section is higher than 200° C. and 350° C. or lower, and the combustion gas from which the sulfur oxide has been removed by the bagfilter flows into the denitration section without being heated on the upstream side of the denitration section.

A boiler system is provided including: a boiler that burns fuel containing sulfur content, chlorine content, and water content to generate a combustion gas; a bagfilter that removes sulfur oxide; a denitration section that removes nitrogen oxide; a desulfurizing absorbent supply section that mixes a desulfurizing absorbent into the combustion gas on an upstream side of the bagfilter; and a reformer that mixes a denitrating reagent into the combustion gas on an upstream side of the denitration section, wherein the bagfilter performs dry desulfurization, and a temperature of the combustion gas passing through the bagfilter and flowing into the denitration section is higher than 200° C. and 350° C. or lower, and the combustion gas from which the sulfur oxide has been removed by the bagfilter flows into the denitration section without being heated on the upstream side of the denitration section.

The present invention relates to a method and system for torrefaction of biomass and combustion of generated torrefaction gases. The torrefaction gases released from the biomass during the torrefaction reaction are withdrawn from the reactor and into a first burning zone. A secondary stream of air is introduced to the first burning zone to combust the torrefaction gases whereupon hot flue gases are obtained. Part of the hot flue gases are directed to a mixing unit. The rest of the hot flue gas is directed to a second burning zone for complete combustion of the flue gases. The fully combusted flue gases obtained in the second burning zone are directed to a heat recovery unit where the temperature of the flue gas is decreased. Part of the cold flue gases are directed to the mixing unit where it is mixed with the hot flue gases such that a stream of cooled flue gases is obtained. The stream of the cooled flue gases are diverted into the torrefaction reactor for direct heating of the biomass.