초록 ▼

Steam generation apparatus and methods are presented that are dedicated to oxygen-enriched air combustion of a fuel, wherein the oxygen concentration of the oxygen-enriched air may range from just above 21 percent to 100 percent. One apparatus comprises an oxygen-enriched air preheater through which

Steam generation apparatus and methods are presented that are dedicated to oxygen-enriched air combustion of a fuel, wherein the oxygen concentration of the oxygen-enriched air may range from just above 21 percent to 100 percent. One apparatus comprises an oxygen-enriched air preheater through which oxygen-enriched air flows and exchanges heat indirectly with flue gas, creating a preheated oxygen-enriched air stream. The apparatus further comprises a boiler having a radiant section and a convection section, and other heat transfer units adapted to handle reduced flue gas flow rate and higher temperature flue gases than comparable air/fuel combustion boilers, thus allowing a smaller heat transfer surface area, a more compact design and a higher efficiency.

대표청구항 ▼

Steam generation apparatus and methods are presented that are dedicated to oxygen-enriched air combustion of a fuel, wherein the oxygen concentration of the oxygen-enriched air may range from just above 21 percent to 100 percent. One apparatus comprises an oxygen-enriched air preheater through which

Steam generation apparatus and methods are presented that are dedicated to oxygen-enriched air combustion of a fuel, wherein the oxygen concentration of the oxygen-enriched air may range from just above 21 percent to 100 percent. One apparatus comprises an oxygen-enriched air preheater through which oxygen-enriched air flows and exchanges heat indirectly with flue gas, creating a preheated oxygen-enriched air stream. The apparatus further comprises a boiler having a radiant section and a convection section, and other heat transfer units adapted to handle reduced flue gas flow rate and higher temperature flue gases than comparable air/fuel combustion boilers, thus allowing a smaller heat transfer surface area, a more compact design and a higher efficiency. sure fluid from the superheater which is expanded to produce a low pressure fluid, and means to route the low pressure fluid to a reheater, the reheater allowing heat exchange between flue gas and said low pressure fluid. 12. The apparatus of claim 1 comprising means for local flue gas recirculation. 13. A method of operating the steam generation apparatus of claim 1 having reduced heat transfer area and increased efficiency for an equivalent air/fuel power production base case, comprising: a) flowing the oxidant through the oxidant preheater and exchanging heat indirectly with the flue gas exiting the boiler, thus forming a preheated oxidant, the oxidant selected from the group consisting of oxygen-enriched air and oxygen; b) introducing the fuel and the preheated oxidant into the furnace of the boiler and combusting the fuel with the preheated oxidant to generate the flue gas and thermal energy, the flue gas having a flow rate that is reduced compared to the base case; and c) feeding the boiler with boiler feed water and circulating the water through the plurality of convection heat transfer section tubes and the purality of radiant heat transfer section tubes, in order to preheat and evaporate the water, and produce superheated steam by heat transfer between the flue gas and the boiler feed water. 14. The method of claim 13, wherein said oxygen-enriched oxidant has an oxygen concentration of at least 90%. 15. The method of claim 13, wherein said fuel is coal. 16. The method of claim 13, wherein a cost of emission control technologies to control release of species comprising those selected from the group consisting of CO2, NOx, SOx, particulate matter, and combinations thereof, is reduced due to the reduced flue gas flow rate and to a more concentrated form of said flue gas. 17. The method of claim 13 comprising flowing the flue gases through means for emission control after traversing the oxidant preheater. 18. The method of claim 13 comprising flowing a portion of the flue gases through means for flue gas recirculation prior to traversing the oxidant preheater. 19. The method of claim 13 comprising flowing a portion of the flue gases through means for flue gas recirculation after traversing the oxidant preheater. 20. The method of claim 15 comprising pulverizing said coal prior to said introducing step.