Abstract:
A system and method for drying pulverized high moisture fuel for use in a selective catalytic reduction system equipped combustion system is provided. The combustion system includes a mill for pulverizing fuel, an air heater, a booster air heater and a fuel duct for feeding dried pulverized fuel to a combustion furnace.
Abstract:
The present disclosure relates to a method of milling a fuel for an oxy-fuel combustion burner (9), the method comprising: separating air into a hot nitrogen gas stream, having a temperature of at least 150°C and a purity of at least 98 mol-% nitrogen, and an oxygen gas stream; leading at least a part of the nitrogen gas stream to a fuel mill (2); milling the fuel by means of the fuel mill (2) in a nitrogen rich atmosphere formed by means of the nitrogen gas stream; leading the at least a part of the nitrogen gas stream away from the milled fuel; leading the oxygen gas stream to the oxy-fuel combustion burner (9); conveying the milled fuel to the oxy-fuel combustion burner (9); and burning the fuel, by means of the oxy-fuel combustion burner (9), in an oxygen rich atmosphere formed by means of the oxygen gas stream. The present disclosure further relates to a system for milling a fuel for an oxy-fuel combustion burner as well as to a power plant comprising such a system.
Abstract:
A combustion burner includes a mixture nozzle (2) defining a mixture fluid passage through which a mixture fluid (1) containing pulverized coal and conveyor gas flows toward a furnace, secondary and tertiary air passages surrounding rthe mixture nozzle (2), through which secondary air (6) and tertiary air (9) for combustion purposes flow, respectively; and air injection nozzles (24) provided in the vicinity of an outer periphery of a distal end of the mixture nozzle (2). The air (21) is injected from the air injection nozzles (24) toward the axis of the mixture nozzle, so that the high-temperature gas in the vicinity of the outer periphery of the distal end of the mixture nozzle (2) is drawn into the mixture fluid (1) in the vicinity of the outer periphery of this distal end.
Abstract:
PROBLEM TO BE SOLVED: To provide a method for operating a pulverized coal-fired boiler facility capable of safely using upgraded low-grade coal as fuel of the pulverized coal-fired boiler and of using the upgraded low-grade coal as fuel without the need to remodel an existing pulverized coal-fired boiler facility so much.SOLUTION: The method for operating a pulverized coal-fired boiler facility 100 using upgraded brown coal as fuel. Boiler exhaust gas taken out of an exhaust gas duct 31 between a desulfurizing tower 6 and a chimney 7 is added to air from a primary air fan 10 to prepare mixed gas. Then, the mixed gas is caused to separately flow to a carrier gas duct 33 through a GAH 8 and a bypass carrier gas duct 34 that bypasses the GAH 8. After this, the mixed gas is supplied to a mill 21. A mixed gas with an oxygen concentration of less than 12% in a volume ratio is supplied to the mill 21.
Abstract:
미분쇄 석탄을 생산하기 위한 방법은 건조가스를 고온 가스 발생기(26) 내에 미리 설정된 온도로 가열하여 제공하는 단계; 상기 석탄 미분쇄기 내에 가열된 건조 가스를 공급하는 단계; 상기 석탄 미분쇄기, 상기 석탄 미분쇄기(20) 분쇄(grinding) 내에 미분쇄 석탄 내의 원형 석탄(Rawl coal)을 제공하는 단계; 상기 석탄 미분쇄기(20)로부터 건조 가스 및 미분쇄 석탄의 혼합물을 수집단계 및 필터(34)에 혼합물을 공급하는 단계; 상기 필터(34)는 상기 건조 가스로부터 상기 건조된 미분쇄 석탄을 분리하며, 더 사용하기 위하여 상기 건조된 미분쇄 석탄을 수집하는 단계 및 필터로부터 배기 라인(38)까지 상기 건조된 가스를 공급하는 단계; 및 상기 필터에 존재하는 건조 가스를 수집하는 단계 및 상기 고온 가스 발생기에 재순환 건조 가스를 공급하기 위하여 재순환 라인에 상기 수집된 건조 가스를 공급하는 단계를 포함한다. 상기 건조 가스를 제공하는 단계는 고온 스토브 폐기 가스 라인을 통해 상기 고온 가스 발생기(26)에서 다양한 유동비의 고온 스토브 폐기 가스룰 공급하는 단계이고, 상기 고온 스토브 폐기 가스의 유동비는 건조가스로 사용된 고온 스토브 폐기 가스의 양을 최대화하기 위하여 선택되어지고, 석탄 미분쇄기 가스 주입구(24)의 건조 가스의 압력은 상기 고온 스토브 폐기 가스 라인(46)을 통해 상기 고온 스토브 폐기 가스의 유동비를 조절한다.