Abstract: Systems for stabilizing combustion while minimizing NOx generation by using high-flame-speed additives to stabilize the flame front in combustors operating at relatively low temperatures and/or under oxygen constraints. The system is adapted for use in coal-fired boilers, oil-fired boilers, and gas turbine engines. The methods stabilize the flame front to permit stable combustion under an expanded range of part-load conditions. The system provides substantially complete combustion of coal in coal boilers resulting in ash saleable for use in concrete manufacturing.

Abstract: A combustion chamber (1), in particular in a gas turbine, has at least two burners (A-H) that are connected to a fuel supply (3) via controllable fuel valves (2? and 2). Each burner (A to H) is assigned at least one optical measuring device (4) for detecting chemiluminescent radiation, and the combustion chamber (1) is assigned a pressure sensor (7) for detecting a combustion chamber pressure. The optical measuring device (4) and the pressure sensor (7) are connected to a computing and control device, which calculates a correlation value from the incoming measured values. A high correlation value signifies that the associated burner is prone to pulsation. The computing and control device (6) is designed in such a way that it determines the burner or a burner group with the highest correlation and controls the associated fuel valve(s) in such a way that more fuel is fed to the respective burner or the respective burner group, and the pulsation tendency thereof is thereby reduced.

Abstract: In a combustor (1) for a gas turbine, the combustor (1) includes a burner system (2) and a fuel supply system (3). The burner system (2) includes at least two burner groups (A, B) each with at least one burner (5). The fuel supply system (3) includes a main line (7), which is connected to a fuel source (8), and also an auxiliary line (9) for each burner group (A, B). Each auxiliary line (9) is connected to each burner (5) of the associated burner group (A, B) and is connected to the main line (7) by a controllable distribution valve (10). A sensing system (11) measures pressure pulsation values and/or emission values for each burner group (A, B). A control system (12), in dependence upon the pulsation values and/or the emission values, controls the distribution valves (10) so that in each burner group (A, B) the pulsation values and/or the emission values assume and/or fall below predetermined threshold values.

Abstract: What are described are a multiple burner arrangement and a method for operating such a multiple burner arrangement with a multiplicity of individual burners which are designed as premix burners and which serve for firing a combustion chamber of a thermal engine and each have a swirl space into which combustion supply air and fuel can be introduced so as to form a swirl flow, the swirl flow forming downstream of the premix burner, within the combustion chamber, a backflow zone in which a burner flame is formed.

Abstract: A gas turbine installation (1), in particular in a power plant for generating electricity, includes a turboset (2) having a turbine (4), a compressor (5) and a combustion chamber (6) arranged in a gas path (9) connecting the compressor (5) to the turbine (4), and a flue gas recirculation device (3), which passes combustion flue gas from the turbine (4) from a flue gas path (14) connected to the turbine (4) via a recirculation path (16) to a fresh gas path (13) connected to the compressor (5). To improve the efficiency of the gas turbine installation (1), a control device (17) controls a volumetric flow and/or a temperature of the recirculated combustion flue gases in such a way that a fresh gas/flue gas mixture which enters the compressor (5) is at a predetermined desired temperature.

Abstract: The invention relates to a burner for premix-type combustion having a cavity which has at least one tangential air inlet slot for the supply of a combustion air flow, a device for the injection of fuel into the cavity which is provided in the region of a burner axis, and a device for the injection of premix fuel into the air inlet slots which is provided centrally in the inflow region of the combustion air flow. The device for the injection of premix fuel into the air inlet slots has at least one fuel supply, the fuel outlet openings of which are arranged in such a way that the premix fuel is introduced into the combustion air flow on both sides of the at least one fuel supply related to a cross-sectional plane at right angles to the burner axis.

Abstract: A burner (1) for heat generation, in particular in a gas turbine, is disclosed as well as a method for the stabilization of the flame of a burner (1). The burner (1) comprises inlet openings (3) for a combustion air stream, at least a swirl generator (2) for the combustion air stream and one or more first fuel supplies (4) with first fuel outlet openings (5) for injection of fuel into the combustion air stream. At least one resonance tube (6) with an open (7) and an essentially closed end (8) is arranged in or at the burner (1), whose closed end (8) is positioned in the region of a flame front (9) which forms during operation of the burner (1) on the side of the burner (1). An outlet opening (10) of a supply (11) for a compressible medium is arranged at the open end (7) of the resonance tube (6).

Abstract: A burner (1) for heat generation, in particular in a gas turbine, is disclosed as well as a method for the stabilization of the flame of a burner (1). The burner (1) comprises inlet openings (3) for a combustion air stream, at least a swirl generator (2) for the combustion air stream and one or more first fuel supplies (4) with first fuel outlet openings (5) for injection of fuel into the combustion air stream. At least one resonance tube (6) with an open (7) and an essentially closed end (8) is arranged in or at the burner (1), whose closed end (8) is positioned in the region of a flame front (9) which forms during operation of the burner (1) on the side of the burner (1). An outlet opening (10) of a supply (11) for a compressible medium is arranged at the open end (7) of the resonance tube (6).

Abstract: In a method of producing cement clinker and electricity, cement raw mix and hydrocarbon are fed in a circulating fluidized bed boiler (1). Therein cement raw mix is calcined and steam is produced. Gas and solids out of the fluidized bed enter a cyclone (8), the solids being separated therein and returned to the bed. Part of those solids are first cooled down in a solids heat exchanger (9) producing steam. Fly ash consisting predominantly of lime and gas escaping the cyclone are passed through a heat exchanger (28, 33) and a filter (37). Hot bed material is discharged from the circulating fluidized bed and is ground with additives, then blended with lime being separated in the filter (37), then supplied to a rotary kiln (16), wherein the solids are clinkered. The produced steam is fed to a steam turbine island (42).

Abstract: A method of producing a calcined raw meal and of producing additional steam in an existing steam generator comprises the following steps: pulverized raw meal, hydrocarbon, primary air and secondary air are fed to a calciner system (60), wherein the raw meal is calcined in a temperature range between 850° C. and 950° C., the calcined raw meal is separated from the calciner flue gases at the exit of the calciner system, the calcined raw meal is directed through a cooler (70), in which it exchanges its heat with the secondary air, the calciner exhaust gases are directed in the gas path of the backpass of the steam generator (1) at an appropriate temperature window and are used for steam production. The raw meal consists mainly of limestone (CaCO3) and the calcined material is mainly lime (CaO). The fuel feed (4) to the steam generator (1) is reduced during introduction of the exhaust gases into its backpass.

Abstract: A firing system for a thermal cracking furnace is provided. The firing system includes a plurality of air inlets for introducing air into the furnace interior, the air inlets being generally arrayed along a lengthwise row on the floor of the furnace at a predetermined proximity to one of the sidewalls, and a plurality of start up fuel ports disposed intermediate the row of air inlets and the radiant coils of the furnace. The firing system also includes a plurality of normal operation fuel ports disposed intermediate the row of start up ports and the radiant coils and an assembly for selectively controlling the overall supply of fuel to the start up fuel ports and the normal fuel operation ports to effect supply of fuel solely to the start up fuel ports during a start up mode of operation of the firing system and supply of fuel solely to the normal operation fuel ports during a normal mode of operation.

Abstract: A method of operating a pulverized coal-firing furnace so as to achieve no more than a predetermined variation in the instantaneous vertical velocities of the flow exiting a combustion chamber of the furnace is provided. The method includes, in one variation thereof, providing a series of lower compartments for introducing therethrough one of air, fuel, and air and fuel into the combustion chamber. At least one upper compartment is disposed above the topmost compartment of the series of lower compartments at a relative disposition to the topmost compartment in a spacing range between a contiguous disposition to a more spaced disposition which is no more than twice the average spacing between any given compartment and an adjacent compartment.

Abstract: A method of operating a pulverized coal-firing furnace is provided which includes injecting air from an upper compartment generally in opposition to a swirling fireball. The method also provides the step of sensing a temperature characteristic of one side of a convection pass of the furnace. The sensed value, in accordance with the method of the present invention, is then evaluated to determine if the sensed value of the temperature characteristic exceeds an allowable value. In response to a determination that the temperature characteristic exceeds the allowable value, the momentum of the air injected through the upper air compartment is changed. After the step of changing the momentum of the air injected through the upper air compartment, the temperature characteristic of the one convection pass location is sensed to obtain a post adjustment value of the temperature characteristic and compared to an allowable value.

Abstract: The flue gas temperature coming from an air preheater to a particulate collection device such as an electrostatic precipitation or fabric filter is reduced to improve the operation of the particulate collection device. This may be done by reducing the exit flue gas temperature from the air preheater or reducing the temperature after exiting. In one embodiment, air in excess of that needed for combustion is passed through the air preheater with the heated excess air either being dumped or used for a variety of purposes in the plant. A particular embodiment involves segmenting the air outlet side of a rotary regenerative air preheater and withdrawing the excess air from the segment where the dust loading is the lowest. Further, additional cooling of the flue gas can be provided by reducing the quantity of primary air that typically bypasses the air preheater and then providing other ways to control the primary air temperature to the pulverizers.

Abstract: A minimum recirculation flame control (MRFC) solid fuel nozzle tip (12) that is suited to being cooperatively associated with a pulverized solid fuel nozzle (34) of a firing system in a pulverized solid fuel-fired furnace (10). The MRFC solid fuel nozzle tip (12) includes a secondary air shroud (46), secondary air shroud support (50) operative for supporting the primary air shroud (48) relative to the secondary air shroud (46), and a splitter plate (52) mounted in supported relation within the primary air shroud (48).

Abstract: A method for effecting control over a radially stratified flame core burner that is particularly suited for employment in a firing system of a fossil fuel-fired furnace for purposes of reducing the NO.sub.X emissions from the fossil fuel-fired furnace. The subject method for effecting control over a radially stratified flame core burner enables the foregoing to be accomplished while yet at the same time minimizing CO emissions and the opacity of the exhaust from the stack of the fossil fuel-fired furnace without extending the envelope of the flame produced by the radially stratified flame core burner.

Abstract: An inverse combined steam-gas turbine cycle is disclosed. In the steam cycle, a fuel having a high nitrogen content such as coal or heavy fuel oil is burned in a boiler to raise steam to power a steam turbine. In the gas turbine cycle, a hydrocarbon fuel such as natural gas is burned in a gas combustor to power a gas turbine. The compressed exhaust gas (40. 42) from the steam cycle combustion is introduced into the gas combustor, where nitrogen oxides (NO.sub.x) in the exhaust gas may be reduced through reactions with the hydrocarbon fuel.

Abstract: An apparatus for detecting the presence of polycyclic aromatic hydrocarbons in the effluent of a turbulent commercial combustion system for monitoring or controlling the composition of the effluent. The apparatus is a system for directyl selectively detecting the presence in the effluent high molecular weight polycyclic aromatic compounds having five or more rings by laser induced fluorescence. The system includes an illuminating source of select fluorescence excitation of wavelengths that induces substantial fluorescence by high molecular weight polycyclic aromatic hydrocarbons in the gas phase.

Abstract: Low NO.sub.x burners for the combustion of gaseous, liquid and solid fuels. The fluid dynamic principle of radial stratification by the combustion of swirling flow and a strong radial gradient of the gas density in the transverse direction to the axis of flow rotation is used to damp turbulence near the burner and hence to increase the residence time of the fuel-rich pyrolyzing mixture before mixing with the rest of the combustion air to effect complete combustion.

Abstract: Detecting the presence of PAC's in the effluent of a combustions system by detecting the presence of a high molecular weight PAC's having five or more rings. A position along the effluent stream is selected at which high molecular weight PAC's may be present. The effluent is illuminated with radiation having a wavelength absorbed by the high molecular weight PAC's in the gas phase. The fluorescence from the illuminated effluent is detected, and analyzed by comparison to the known fluorescence of high molecular weight PAC's in the gas phase to determine the presence of the PAC's in the effluent. The effluent composition may be controlled in response to the detection.