A solid fuel burner is provided with a guide member arranged on an outer circumferential section of a distal end of a first gas nozzle so as to guide a fluid flowing through a second flow passage outward in a radial direction; and a contraction forming member that is arranged on an upstream side of the guide member with respect to the flow direction of the second flow passage so as to reduce the cross sectional area of the second flow passage. An outer diameter of the guide member is formed to be smaller than an inner diameter of an outer peripheral wall of a second gas nozzle. The first gas nozzle, the guide member, and the contraction forming member are configured so as to be integrally attachable/detachable along an axial direction of the first gas nozzle toward the outside of a furnace.

The present disclosure provides a carbon-based oxygen-enriched combustion method for recirculation of flue gas from a cement kiln. The combustion method includes recirculating the flue gas generated by the cement kiln to a certain degree to concentrate and enrich carbon dioxide in the flue gas of the cement kiln, mixing the carbon dioxide-rich recirculating flue gas of the cement kiln with the pressurized oxygen to obtain the carbon-based oxygen-enriched products, and mixing the carbon-based oxygen-enriched products with the atmospheric-pressure oxygen to obtain carbon-based air which serves as combustion-supporting gas of the cement kiln.

The invention provides a combustion apparatus and a combustion method capable of ashing matter to be combusted inside a combustion chamber efficiently without providing a device such as an unburned combustibles measurement device and without varying the direction of injection of air into the combustion chamber. The powder fuel combustion apparatus 1 includes a fuel supply device 10, a primary combustion chamber 20, a secondary combustion chamber 50, an air supply/ash discharge device 32, and a cyclone dust collector 60. An inclined portion 23a is formed at a bottom portion 23 of the primary combustion chamber 20, and the inclined portion 23a includes bottom portion air supply ports 31 and an air supply/ash discharge device 32. The air supply/ash discharge device 32 includes a bottom portion air injection nozzle 34 and an ash delivery device 35. The bottom portion air injection nozzle 34 has upper and lower ends opened, and a plurality of injection ports 34a through which air is injected are formed on a side surface. During combustion of the powder fuel F, air having a strong wind pressure is injected through the bottom portion air injection nozzle 34 either regularly or irregularly to agitate the powder fuel F and achieve a good combustion state.

The present invention relates to a device and a method for chemical looping combustion, for which the end of the intake duct (4) opening out within the chamber of the separator (1) is inclined with respect to a horizontal plane (H).

The present disclosure is directed to systems and methods for high flame temperature oxy-combustion that enables the capture of CO.sub.2 cost effectively. One part of the presently disclosed subject matter comprises an annular shroud burner which utilizes a supply of undiluted oxygen and minimal flue gas recycle to generate a high flame temperature to maximize efficiency. The annular shroud burner may deliver oxygen into a combustion zone where mixing of the oxygen and a stream of fuel occurs. Flue gas recycled from the exit of the combustion system serves the dual purpose of conveying the coal into the reaction zone, as well as providing local cooling and protection from high incident heat fluxes through the novel shroud cooling design. The annular shroud burner may be configured to produce an axial jet flame that controls the rate of mixing of oxygen and fuel, thereby extending the heat release. Oxygen and coal may be mixed in a ratio such that peak flame temperatures exceed 4,500° F. (2,482° C.) while the flow of recycled flue gas is regulated to control flame temperature and protect burner components and near-burner surfaces.

A double chambers boiler system with oxygen-enriched combustion is provided, relating to fields of thermal power engineering and mechanical manufacturing. The double chambers boiler system includes a boiler furnace subassembly and a combustion control subassembly. The boiler furnace subassembly includes a combustion chamber and a heat exchange chamber. The heat exchange chamber is arranged above the combustion chamber. A high temperature flue gas outlet is arranged between the combustion chamber and the heat exchange chamber. The combustion control subassembly includes a burner, a pure oxygen injector and a fuel injector. The double chambers boiler system with oxygen-enriched combustion is able to simultaneously solve problems of improving a combustion efficiency and reducing an emission concentration of NO.sub.x.

The present disclosure is directed to systems and methods for high flame temperature oxy-combustion that enables the capture of CO.sub.2 cost effectively. One part of the presently disclosed subject matter comprises an annular shroud burner which utilizes a supply of undiluted oxygen and minimal flue gas recycle to generate a high flame temperature to maximize efficiency. The annular shroud burner may deliver oxygen into a combustion zone where mixing of the oxygen and a stream of fuel occurs. Flue gas recycled from the exit of the combustion system serves the dual purpose of conveying the coal into the reaction zone, as well as providing local cooling and protection from high incident heat fluxes through the novel shroud cooling design. The annular shroud burner may be configured to produce an axial jet flame that controls the rate of mixing of oxygen and fuel, thereby extending the heat release. Oxygen and coal may be mixed in a ratio such that peak flame temperatures exceed 4,500° F. (2,482° C.) while the flow of recycled flue gas is regulated to control flame temperature and protect burner components and near-burner surfaces.

A modular boiler system for implementing fuel combustion is provided. The system includes a first boiler and a second boiler of a plurality of boilers, an oxygen input unit, a fuel input unit, a recycled flue gas input unit, and a flue gas separator. The first boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and recycled flue gas from the recycled flue gas input unit. The first boiler outputs intra-system flue gas. The flue gas separator separates the intra-system flue gas into a first and second flue gas stream, transfers the first flue gas stream to the second boiler, and transfers the second flue gas stream to a gas cleaning system. The second boiler receives oxygen from the oxygen input unit, fuel from the fuel input unit, and the first flue gas stream from the flue gas separator.

A method of operating a furnace having a firing system is disclosed. The method includes providing a solid fuel to a sieve; separating the fuel into a portion and a second portion; providing a first portion of a flue gas to a first fuel dryer comprising a first duct; providing the first portion of fuel to the first duct, and drying the first portion of fuel therein; conveying the first portion of fuel through the first duct to the furnace; burning the first portion of fuel with firing system; conveying the second portion of fuel and a second portion of the flue gas to a second fuel dryer in a lower portion of the furnace, providing the second portion of fuel to a mill; pulverizing the second portion of fuel with the mill; conveying the second portion of fuel to the furnace; and burning the second portion of fuel.

A modular pressurized combustion system for flexible energy generation is provided. The system comprises a plurality of pressurized combustion boilers, at least one compressor configured to provide pressurized oxidizer gas to each of the plurality of pressurized combustion boilers in parallel, and at least one feeder configured to provide fuel to each of the plurality of pressurized combustion boilers in parallel. The system further comprises a flue gas input unit configured to provide recycled flue gas to each of the plurality of pressurized combustion boilers in series, at least one pressurized heat recovery unit configured to receive a flue gas output stream from each of the plurality of pressurized combustion boilers, and at least one particle filter configured to filter a flue gas output stream from the pressurized heat recovery unit. The system also comprises an integrated pollutant removal unit.