Abstract: A burner assembly in which an inlet is provided for receiving a mixture of particulate fuel and air, an outlet extending at an angle to the axis of said inlet. A passage connects the inlet and the outlet for passing a portion of the mixture directly from the inlet to the outlet, and a chamber communicates with the inlet for receiving a second portion of the mixture. The chamber is constructed and arranged to swirl the second mixture portion and direct it towards the passage for passing to the outlet. As a result, particle fracture and friction losses are minimized and the burner assembly can operate at relatively low pressures.A burner section communicates with the inlet section and includes an inlet for receiving the fuel-air mixture from the outlet of the inlet section, and an outlet for discharging the mixture into a furnace.

Abstract: A multi-stage topping combustor unit having rich burn, and lean burn zones followed by a quench/dilution zone. Combustible fuel gas is supplied only to the rich burn zone, and an oxygen-containing air-flue gas mixture is supplied to all three zones in a fixed flow proportioning that establishes a desired temperature profile through the combustor unit that minimizes combustor NOx and CO emissions. The combustor unit casing is cooled by an augmented air and oxygen stream discharged into the rich burn zone only, or into both the rich and lean burn zones. The cooling air flow is regulated by a control device/valve that allows the cooling air flow, and hence the augmenting oxygen entering the rich burn zone or the rich and lean burn zones, to be reduced as the fuel gas flow/firing temperature is reduced.

Abstract: An air damper assembly for a coal-fired furnace in which a damper sleeve extends between two spaced walls adjacent the furnace in a manner to define an air inlet. A threaded support member is connected to the damper, and a threaded shaft is in threaded engagement with the support member. Rotation of the shaft causes corresponding movement of the support member, and therefore the damper, to vary the size of the opening and therefore the amount of air introduced into the furnace.

Abstract: A hybrid steam generating system and method in which fluid is passed through the waterwall tubes of a furnace to transfer heat from the furnace to the fluid to convert at least a portion of the fluid to steam. Under certain operating conditions, the heated fluid is passed from the furnace to a separator for separating the steam from the heated fluid and the separated heated fluid is passed from the separator back to the furnace. The steam from the separator is passed to a steam utilization unit, and, under certain operating conditions, the heated fluid is passed from the furnace directly to the steam utilization unit.

Abstract: Piping systems adapted for handling fluids such as steam and various process and hydrocarbon gases through a pressure-reducing device at high pressure and velocity conditions can produce severe acoustic vibration and metal fatigue in the system. It has been determined that such vibrations and fatigue are minimized by relating the acoustic power level (PWL) generated in the piping system to being a function of the ratio of downstream pipe inside diameter D.sub.2 to its wall thickness t.sub.2. Additionally, such vibration and metal fatigue can be further minimized by relating the fluid pressure drop .DELTA.p and downstream Mach number M.sub.2 to being a function of the ratio of downstream piping inside diameter D.sub.2 to the pipe wall thickness t.sub.2, as expressed by M.sub.2 .DELTA.p=f (D.sub.2 /t.sub.2). Pressure-reducing piping systems designed according to these criteria exhibit minimal vibrations and metal fatigue failures and have long operating life.

Abstract: A fluidized bed combustion system in which a partition is disposed in an enclosure to divide the enclosure into two furnace sections for receiving beds of combustible particulate material. Air is introduced into each bed in quantities sufficient to fluidize the material and insufficient to completely combust said material, and additional air is introduced through said partition and into said sections in quantities sufficient to completely combust said material. An equalization port is provided through the partition for equalizing the pressure between the furnace sections.