Abstract:
Beschrieben wird eine Wärmekraftlanlage mit sequentieller Verbrennung und reduziertem CO 2 -Ausstoss, die folgende über jeweils wenigstens einen Strömungskanal (S) in Serie miteinander verbundene Komponenten aufweist: eine Verbrennungszuluft-Kompressoreinheit (1), eine erste Brennkammer (2), eine Hochdruckturbinenstufe (3), eine zweite Brennkammer (4) sowie eine Niederdruckturbinenstufe (5), wobie die zweite Brennkammer (4) und/oder die Niederdruckturbinenstufe (5) zu Kühlzwecken mit einem Kühlgasstrom versorgbar sind. Ferner wird ein Verfahren zum Betrieb einer derartigen Wärmekraftanlage beschrieben. Die Erfindung zeichnet sich dadurch aus, dass eine Rezirkulationsleitung (6) vorgesehen ist, die wenigstens einen Teil eines aus der Niederdruckturbinenstufe (5) austretenden Abgasstroms einer Verdichtereinheit (7) zuführt, dass eine Kühlleitung (8) vorgesehen ist, die wenigstens einen Teil des aus der Verdichtereinheit (7) austretenden komprimierten Abgasstroms als Kühlsgasstrom der zweiten Brennkammer (4) und/oder der Niederdruckturbinenstufe (5) zu Kühlzwecken zuführt, und dass in der Kühlleitung (8) eine CO 2 -Abscheideenheit (9) vorgesehen ist, die zumindest Anteile von CO 2 aus dem Kühlgasstrom separiert.
Abstract:
A method of combustion comprising providing fuel (13) to a turbine combustor (14), supplying air (21) to form a fuel/air mixture having an equivalence ratio greater than 0.55 supplying cooled combustion gases (37) and mixing with the air such that the mixture oxygen is less than 18 %, and supplying the mixture to the combustor (14).
Abstract:
A method and apparatus whereby flameless combustion may be precipitated and sustained within the essentially oval combustion chamber of an integrated heater/burner apparatus. The invention provides for an air inlet and fuel source in combination with recirculating flue gas within the apparatus combustion chamber to precipitate and maintain flameless combustion of the combined gases along, and within, a narrowly defined boundary. Air is introduced to the oval combustion chamber via an air inlet. Fuel gas is combined with recirculating flue gases with continued heating of the recirculating flue gas, introduced air or both flue gas and air, until the temperature at the boundary interface between the air and inerted fuel gas exceeds an auto ignition temperature of the boundary interface components. A fuel gas stream absent a flamed portion thereof is combined with the recirculating flue gas and then allowed to diffuse with the air stream in a measure sufficient to sustain flameless combustion and chamber operational temperature of generally between 1500°F and 1900°F. The essentially oval configuration of the integrated heater/burner allows for increased mass and circulation rates beyond that possible with heaters of the contemporary art and as a consequence thereof provides for uniform, complete and cooler combustion resulting in low NOx emissions.
Abstract:
A burner for use in furnaces such as in steam cracking. The burner is located within a first flame opening in a furnace and includes a primary air chamber (26), a burner tube (12) including a downstream end (18), an upstream end (16) in fluid communication with the primary air chamber and a burner tip (20) mounted on the downstream end of the burner tube and directed to the first flameopening in the furnace so that combustion of the fuel takes place downstream of the burner tip, at least one flue gas recirculation duct (76) having a first end at a second opening (82) in the furnace and a second end opening into the primary air chamber, and a wall (95) extending into the furnace between the first flame opening and the first end of the flue gas recirculation duct to substantially lengthen a flow path therebetween and thereby providing a substantial barrier to flow.
Abstract:
An improved method and apparatus comprising a shaft furnace (10) for increasing the productivity of a direct reduction process in which iron is reduced to metallized iron with hot reducing gas.
Abstract:
A NOx reduction burner system and process. Fuel modification and fuel rich reactor zone (18) gases are brought together with products from a fuel lean reactor zone (20) in a low temperature burnout and NOx reduction reactor zone (22). The fuel modification fuel rich reactor (18) stabilizes combustion through recirculation of hot gases to the reactants. Nitrogenous species decay reactions in the fuel rich zone controls the production of NOx. The nitrogenous species from the fuel rich zone (18) and the NOx from the fuel lean zone (20) then react in the burnout zone (22) at an optimal temperature and nitrogenous species mix where NOx is minimized. Temperature in all zones, and in particular the burnout zone, can be controlled by furnace gas entrainment, induced flue gas recirculation, force flue gas recirculation and active cooling by radiative and/or convective heat transfer. NOx can be even further reduced by introducing ammonia, or a like amine species, into the low temperature burnout zone. By balancing combustion and emissions control reactions over several zones, low emissions can be achieved under good flame stability, turndown, heat transfer and noise characteristics.
Abstract:
The reduction in NOx formation for high temperature applications with hot and regenerative combustion air is accomplished with flame control as follows. Initial NOx formation is reduced by introducing internally recirculated waste gases extracted directly from the chamber atmosphere adjacent to the burner quarl and a regulated air flow into the fuel stream. This stream of gases intersects with a ring of combustion air sufficient in flow rate to initiate the combustion process on the heavily diluted gas stream perimeter. Further reduction in NOx formation is accomplished by diluting the combustion air with "in chamber" waste gases. The lean burning gas stream is allowed to expand onto the hot face of an air baffle at which localised combustion takes place. The high velocity air streams exiting the air baffle induce waste gases into the overall mixture and the combustion process is completed with the desired air/fuel ratio in the furnace chamber.
Abstract:
A firing system (12) for a thermal cracking furnace (10) is provided. The firing system (12) includes a plurality of air inlets (38) for introducing air into the furnace interior, the air inlets (38) being generally arrayed along a lengthwise row (50) on the floor (20) of the furnace (10) at a predetermined proximity to one of the sidewalls (14), and a plurality of start up fuel ports (32) disposed intermediate the row of air inlets (38) and the radiant coils (22) of the furnace (10). The firing system (12) also includes a plurality of normal operation fuel ports (42) disposed intermediate the row of start up fuel ports (32) and the radiant coils (22) and an assembly (36) for selectively controlling the overall supply of fuel to the start up fuel ports (32) and the normal fuel operation ports (42) to effect supply of fuel solely to the start up fuel ports (32) during a start up mode of operation of the firing system (12) and supply of fuel solely to the normal operation fuel ports (42) during a normal mode of operation.
Abstract:
Method for low pollution power generation by combusting a fuel with a supply of highly concentrated oxygen in a combustion chamber (714), to which recirculated combustion products are introduced for temperature control, characterized in that all or parts of the combustion products are cooled (727) to an appropriate temperature which keeps all or most of the water vapor from condensing from said products, before said products are compressed and recirculated to the combustion chamber.
Abstract:
A low NOx burner and related method are disclosed including the steps of supplying a first reactant stream and introducing a second reactant stream into the first reactant stream at a first point so as to produce co-flowing streams. This resulting fuel/oxidant stream is discharged into a furnace environment having inert combustion products substantially equilibrated to furnace temperature, so as to entrain the combustion products and mix them together with the co-flowing stream. The temperature of the co-flowing stream is increased by the entrained products until it ignites in a combustion region displaced from the first point. Thus ignition cannot occur until the reactant stream has been diluted by inert products of combustion, reducing both oxygen concentration and peak flame temperature, so as to suppress NOx production.