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Rjm Corporation

Rjc Corporation

Richard J Monro

R Gifford Broderick

Peter D Marx

A method and apparatus are described for reducing NO.sub.x in a combustion zone such as a boiler by spatially selectively injecting a cooling fluid into the combustion zone so that the fluid is entrained to intersect an identifiable NO.sub.x producing zone. The cooling fluid can be water or a gas or mixture of them and whose temperature is sufficiently low or whose combined mass flow and temperature are sufficiently low so that the cooling fluid can reach the NO.sub.x producing zone and cool it to a temperature where the NO.sub.x production is significantly reduced. In one embodiment of the invention a cyclone boiler has a number of identifiable NO.sub.x producing zones. Several of these are targeted by spatially distinct cooling fluid streams placed at strategic locations. At one location the cooling fluid such as a water spray is placed in a duct in the path of the secondary air to deliver a cooling secondary air stream or a combination thereof with a hot flue gas and which is shaped to correspond in cross-section to that of the NO.sub.x producing zone targeted by the cooling fluid. Significant NO.sub.x reduction is achieved.

Method and apparatus for reducing nitrogen oxides using spatially

A fuel atomizer using a spray plate, for a highly spun liquid fuel is described for generating spaced apart fuel rich zones separated by a fuel lean zone by forming a slot in an outer domed surface of the spray plate. The shape of the domed surface is selected so that the spinning fuel, which is also under a high pressure, is permitted to preferentially expand in the direction of the ends of the slot while increasingly spilling over a wall bounding the slot. With a fuel atomizer in accordance with the invention substantial reductions in the generation of thermal NOx can be achieved in boilers when the fuel atomizer is placed within a flame stabilizer.

Fuel atomizer and apparatus and method for reducing NOx

A burner flame stabilizer which circumferentially stages the air to form circumferentially-spaced fuel rich and fuel lean zones for lowering of NO.sub.x is described. A circumferential solid fuel stager is described, which operates with a fuel stabilizer to provide increased dwell time for coal particles volatilization in a recirculation zone established by the flame stabilizer. Various embodiments are described.

Internal air and/or fuel staged controller

A flame stabilizer for a burner of solid fuel, such as pulverized coal or sander wood dust, is described whereby the swirl number is varied radially to enhance swirl inducement towards the periphery of the flame stabilizer while more axial flow occurs near the central conduit through which fuel is supplied. The amount of swirl and the amount of combustion air being selected so as to provide an integrated swirl number for the flame stabilizer in the range from about 0.6 to about 2.0. A pressure control ring is described with which the static pressure in the windbox is increased to a level where flame pulsations attributable to low static pressure in the windbox are reduced while the vortex is maintained. An enhanced axial combustion air flow around the discharge end of the fuel supply conduit is described to modify the position of the adverse pressure gradient boundary in a downstream direction. In one embodiment, the flame stabilizer employs vanes with such orientation and shape as to deswirl an excessively high swirling air flow.

Flame stabilizer for solid fuel burner

A flame stabilizer for a burner of solid fuel, such as pulverized coal or sander wood dust, is described whereby the swirl number is varied radially to enhance swirl inducement towards the periphery of the flame stabilizer while more axial flow occurs near the central conduit through which fuel is supplied. The amount of swirl and the amount of combustion air being selected so as to provide an integrated swirl number for the flame stabilizer in the range from about 0.6 to about 2.0. A pressure control ring is described with which the static pressure in the windbox is increased to a level where flame pulsations attributable to low static pressure in the windbox are reduced while the vortex is maintained. An enhanced axial combustion air flow around the discharge end of the fuel supply conduit is described to modify the position of the adverse pressure gradient boundary in a downstream direction.

A method and apparatus for improving the efficiency of the thermal section of a large scale power plant heat generator in which combustible fuels such as fossil fuels, refuse or other materials are burned are described. Flue gas generated in the heat generators and combustion air are passed in heat exchanger relationship at diametrically opposite sides of a rotary type air preheater. The heat exchanger relationship is selected so that it causes removal of a substantial amount of heat from the flue gas whose temperature is consequently lowered to a level where a corrosive pollutant such as SO.sub.3 in the form H.sub.2 SO.sub.4 condenses out. During operation the rotor is rotated at a slow speed while a strong localized stream of wash liquid is applied onto a portion of the rotor in the air preheater along a zone selected to enable a drain down of wash liquid before the wetted portion reenters the air flow side. A netralizer liquid is applied in such a manner that a dry barrier layer is formed over the heat exchanger surfaces to protect these against corrosive effects from condensed pollutants for long time periods. Preferred ranges of operating parameters are described to achieve high fuel savings. These parameters include rotor speed, heat capacities of the air flow, the rotor and the washing liquid.

Heat generator

A method and apparatus for improving the efficiency of the thermal section of a large scale power plant heat generator in which combustible fuels such as fossil fuels, refuse or other materials are burned are described. Flue gas generated in the heat generator and combustion air are passed in heat exchange relationship at diametrally opposite sides of a rotary type air preheater. The heat exchange relationship is selected so that it causes removal of a substantial amount of heat from the flue gas whose temperature is consequently lowered to a level where a corrosive pollutant such as SO.sub.3 in the form H.sub.2 SO.sub.4 condenses out. The heat exchange elements of the rotor are sized so that the cross-sectional area of the passages therebetween are small enough to prevent the formation of aerosols of sulfuric acid.

A method and apparatus for improving the efficiency of a heat generator in which combustible fuels such as fossil fuels, refuse, or other materials are burned is described. Flue gas generated in the heat generator and combustion air are passed in heat exchange relationship in a heat exchanger. The heat exchanger is selected so that it removes a substantial amount of heat from the flue gas, whose temperature is consequently lowered to a level where a corrosive pollutant such as SO.sub.3 in the form of H.sub.2 SO.sub.4 is likely to condense out. A pollutant removing liquid is applied onto the portion of the heat exchanger where the flue gas passes through both to scrub the flue gas and protect that portion of the heat exchanger from corrosive effects from condensed pollutants. Particulates and gaseous pollutants are removed from the flue gas and the heat exchanger by the liquid, which may be a neutralizing liquid such as an alkaline solution to provide a protective sheath for the heat exchanger against the effects of corrosive pollutants. In the described illustrative embodiment, the invention is shown in use with a thermal section for a large scale power plant.

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Ridgefield, CT, United States of America

Richard J Monro