Abstract: A staged, high efficiency burner for gaseous, liquid or pulverized solid fuels (including fuels having a high nitrogen content) in which NOX emissions are minimized. The burner includes a burner basket having a base including a throat and a concentric, tubular, frustroconically shaped wall that defines a primary combustion space. The fuel and primary air of about 75% of stoichiometric air are introduced into the basket which has a length so that the fuel has a residence time therein of between about 0.1 to 0.5 second. Secondary air is introduced into the flame downstream of the basket in the form of a multiplicity of individual air streams which are oriented to penetrate the flame and spin it about its axis so as to maintain a substantially cylindrical flame periphery.

Abstract: A heater for heating gases such as turbine exhaust gases to facilitate the extraction of the heat energy carried by such gases or flue gases to reduce their corrosiveness. The heater is defined by burners installed on walls of the duct through which the gases flow. The burner can be operated with heavy fuel oil and normally uses no more primary air than is necessary to ignite the fuel oil atomized by the burner and sustain a flame. The flame is relatively long and narrow and is directed transversely to the gas flow into the duct. Upstream of the burner is a shield to protect the flame from the gas flow. The shield communicates with a register which collects an amount of gas sufficient to provide the balance of the combustion oxygen to fully combust all fuel. From the register the gas flows along inclined passages to the side of the shield facing the flame, the passages directing the gas in the direction of the flame and at an oblique angle in regard thereto.

Abstract: A system for marginally adjusting the fuel flow to a burner to maintain the proper oxygen content in the exhaust from the burner is disclosed. The burner is of the type where both the fuel and air flow rates are adjusted in a substantially fixed ratio in response to load changes on the system with the fuel being adjusted by a fuel control valve mounted in a fuel supply line. A self-operating pressure regulating valve having an actuator responsive to the differential pressure across the fuel control valve is mounted in the fuel line upstream of the fuel control valve. A set point adjustment mechanism is mounted on the regulating valve actuator to adjust the set point of the regulating valve in response to an oxygen controller which senses the oxygen content in the stack gases. The set point adjustment mechanism has a cam assembly which continously adjusts the set point of the regulator actuator by varying the compression on a spring loaded diaphragm therein.

Abstract: Disclosed is a method for firing a kiln as well as a method for producing cement clinker in which pulverized coal is initially entrained in an airflow of about 2% of the theoretical amount of air needed to combust the coal and transport it to a burner. Supplemental primary air heated sufficiently to vaporize volatiles in the coal is mixed with the coal flow in a burner, discharged into the kiln and hence ignited. Secondary combustion air heated to between 800.degree. F. to 1650.degree. F. and more is added in the kiln to effect the substantially complete combustion of the pulverized coal in the kiln.

Abstract: A heater for heating gases such as turbine exhaust gases to facilitate the extraction of the heat energy carried by such gases or flue gases to reduce their corrosiveness. The heater is defined by burners installed on walls of the duct through which the gases flow. The burner can be operated with heavy fuel oil and normally uses no more primary air than is necessary to ignite the fuel oil atomized by the burner and sustain a flame. The flame is relatively long and narrow and is directed transversely to the gas flow into the duct. Upstream of the burner is a shield to protect the flame from the gas flow. The shield communicates with a register which collects an amount of gas sufficient to provide the balance of the combustion oxygen to fully combust all fuel. From the register the gas flows along inclined passages to the side of the shield facing the flame, the passages directing the gas in the direction of the flame and at an oblique angle in regard thereto.

Abstract: A nozzle is disclosed which is capable of simultaneously operating with two different liquid fuels, a first fuel being difficult, and a second fuel being relatively easy to ignite. The nozzle has concentric first, second and third conduits through which the first fuel, atomizing steam and the second fuel flow towards a nozzle cap. The steam is divided into two streams one of which is used to atomized the first fuel outside and downstream of the nozzle end while the second stream is used to atomized the second fuel inside the nozzle. The nozzle cap has openings for discharging the atomized second fuel in surrounding relationship to the first fuel to thereby generate a tubular frame with the second fuel that radiates heat inwardly, thereby facilitating the vaporization of the first fuel and its subsequent combustion.

Abstract: A high efficiency liquid fuel atomizing nozzle for use in conjunction with industrial furnaces is described which employs a pressurized gas such as steam for supplying the atomizing energy. The nozzle typically has a plurality of discharge ports and defines, on its interior, a pressurized fuel compartment and a pressurized steam chamber. A core stream of steam is flowed from the steam chamber along an axis obliquely inclined relative to the longitudinal axis of the nozzle to each port. Liquid fuel from the fuel compartment is flowed towards each core stream and divided substantially equally into a number of fuel branch flows which equals the number of core streams. Each branch flow is then brought generally tangentially into contact with the associated core stream so as to form a substantially homogenous, annular fuel stream which surrounds the core stream.

Abstract: Disclosed is a method for firing a kiln as well as a method for producing cement clinker in which pulverized coal is initially entrained in an airflow of about 2% of the theoretical amount of air needed to combust the coal and transport it to a burner. Supplemental primary air heated sufficiently to vaporize volatiles in the coal is mixed with the coal flow in a burner, discharged into the kiln and hence ignited. Secondary combustion air heated to between 800.degree. F. to 1650.degree. F. and more is added in the kiln to effect the substantially complete combustion of the pulverized coal in the kiln.

Abstract: A burner which has a central liquid fuel atomizing nozzle is disclosed. An inner member defines a steam chamber and is surrounded by a shell that defines a liquid fuel compartment. A conduit extends from the steam chamber forming a steam core flow. A first passage feeds liquid fuel about the steam core flow to form an annular liquid fuel stream thereabout. A second passage forms an outer steam flow which envelops the annular liquid fuel flow. The burner further includes ducts to form a first combustion airflow co-axially about the nozzle, a second combustion airflow which surrounds the first flow, and a third combustion airflow which envelops the second flow and generally protects the furnace wall from coming into contact with the flame generated by the burner.

Abstract: A furnace includes a downdraft combustion chamber, a burner mounted at the top of a combustion chamber for burning particulate ash-containing fuel, and a generally horizontal duct near the lower end of the combustion chamber for withdrawing hot gases rsulting from the combustion. The combustion chamber is downwardly tapered to a relatively small conduit, downward into which molten slag from the ash flows. The slag, upon passing through the conduit, passes into and through a downwardly open slag-receiving chamber below the combustion chamber. The slag falls through out the bottom of the slag-receiving chamber into a volume of water immediately below. A portion of the hot gases is diverted through the slag-receiving chamber in order to maintain the slag-receiving chamber at a sufficiently high temperature so that the slag passing therethrough is prevented from solidifying. The portion of hot gas is then directed to a mill for drying fuel therein prior to combustion.

Abstract: A heater for heating gases such as turbine exhaust gases to facilitate the extraction of the heat energy carried by such gases or flue gases to reduce their corrosiveness. The heater is defined by burners installed on walls of the duct through which the gases flow. The burner can be operated with heavy fuel oil and uses no more primary air than is necessary to ignite the fuel oil atomized by the burner and sustain a flame. The flame is relatively long and narrow and is directed transversely to the gas flow into the duct. Upstream of the burner is a shield to protect the flame from the gas flow. The shield communicates with a register which collects an amount of gas sufficient to provide the balance of the combustion oxygen to fully combust all fuel. From the register the gas flows along inclined passages to the side of the shield facing the flame, the passages directing the gas in the direction of the flame and at an oblique angle in regard thereto.

Abstract: A flame forming burner for simultaneously minimizing excess air consumption while suppressing NO.sub.x emissions. A dual zone air register is provided to supply primary air in substoichiometric quantity into mixture with fuel to produce a flame in a primary zone. Additional air is introduced around the flame and downstream of the initial combustion site in a secondary zone, in sufficient quantity to complete combustion. In the preferred embodiment, primary air is provided through a venturi throat, and secondary air is provided through an annular passage equipped with vanes which generate dual counter-rotating (DCR) air flow surrounding the primary zone. Dampers for each register control the primary to secondary air ratio. Preferably, a divergent, non-circular throat provides flame shaping.

Abstract: A flame-sensing system for a tangentially fired broiler in which a plurality of scanners are positioned on the side walls of the combustion chamber adjacent respective burners, and oriented to sight the flame from the respective burners, rather than the central fireball. Closely spaced coolant-carrying tubes lining the boiler walls are oriented with at least one tube in a serpentine pattern and with two or three tubes displaced laterally and rearwardly of the flame zone to provide space for a viewing port approximately the width of two tubes. The displacement pattern tends to dissipate the heat load on the scanner port to prevent scanner or boiler case overheating.

Abstract: An integrated method is disclosed for preparing and suspension firing of bagasse and the like as the primary fuel for steam power generation in a cane sugar refinery. The method comprises mixing wet bagasse with de-ashed hot flue gases of a steam boiler, thereby drying it; separating bagasse dried thereby from the drying flue gases, capturing substantially all suspended dust; sizing the dried bagasse; directing bagasse fines to temporary storage while grinding and resizing any oversize bagasse; metering out and pneumatically suspending the fines, providing a smooth-flowing fuel responsive to a burner fuel feed control means; combusting the suspended fuel in a scroll feed type burner firing the steam boiler; de-ashing the combustion effluent, and utilizing the resultant flue gases for drying wet bagasse. Alternatively, the wet bagasse may be dried partially by de-ashed hot flue gases and partially by a bagasse fired supplementary hot air dryer, thereby further improving boiler operation efficiency.