Abstract: A self-contained single structure for NOX disposal and heat recovery, comprising a burner means (12), including means to supply NOX (oxides of nitrogen) gases (146) to be reduced, primary air (130) in less-than-stoichiometric flow rate, and gaseous fuel (128) at selected flow rate. The gases flow into a first reducing section (114), in which the fuel is burned in a reducing atmosphere, and the NOX gases are reduced. Fire tubes (124) carrying water or steam are positioned to receive heat from the burning gases. At the outlet of the reducing section precooled stack gases (135) are injected (137) into the flame so as to cool the hot products of combustion. The direction of flow of hot gases is turned to 90.degree. (164) in a second section. At the end of the second section the direction of flow is turned 90.degree.

Abstract: Apparatus for burning the gaseous and carbon particulate products from a kiln in which carbon is being calcined, including a pair of vertical cylindrical vessels, to which the effluent products of calcining are carried, by means of an input conduit, which enters the first vessel in a tangential manner near the bottom end, so that the gases will circulate circumferentially in a spinning flow inside of the vessel, as they progress upwardly to a outlet near the top of the first vessel, which leaves tangentially, and passes to the second vessel and enters it tangentially. The gases then circulate around the inner wall of the second vessel spin flowing downwardly, where they leave near the bottom to enter the stack. Means are provided on the entrance conduit for injecting combustion air into the inlet conduit prior to entry of the effluent products into the first vessel.

Abstract: A corrosion resistant tubular air preheater in which combustion air is heated by heat transfer from flue gases from a furnace. The heat exchanger is of a longitudinal type having a central enclosure of rectangular cross-section in which a plurality of tubular heat transfer elements are mounted. Surrounding the central enclosure is an outer plenum. Cold combustion air enters at the bottom of the outer plenum and circulates around and up the plenum to a series of openings on top of the heat transfer elements. The partially heated combustion air then passes downwardly through metal tubes in the heat transfer elements and then passes outwardly to the furnace. The minimum temperature in metal structure enclosing the combustion gases is controlled by two means. One is the use of insulation in selected areas to limit heat transfer rate to cold air impinging upon metal surfaces.

Abstract: A corrugated plate heat exchanger for effecting temperature transfer between two isolated fluids. The heat exchange elements comprise a plurality of elongated corrugated plates arranged to provide dual isolated flow channels therethrough. The arrangement of the corrugated plates also provides the capability of introducing the first fluid through one end of the exchanger and out the other end while introducing the second fluid at the sides of the exchanger to readily adapt said changer to both counter-flow and cross-flow operations.