Abstract: A heat exchanger and a fluidized bed combustion system and method utilizing same in which the heat exchanger includes a plurality of stacked sections. The sections include an inlet section for receiving the particles and a plurality of stacked sections and are arranged in such a manner that the particles are introduced into an upper level of the sections and pass through these sections to a lower level of sections before returning to the furnace. A portion of the stacked sections contain heat exchange surfaces for removing heat from the particles, and a multi-sectioned outlet compartment is provided to receive the separated particles from the heat exchange sections and directly from the inlet section and pass the particles back to the furnace.

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.

Abstract: A damper for fluid flow control has a curved extension plate positioned with respect to the circular path defined by the end of a pivotal damper blade to provide close control of the effective open area over a wide range of damper openings. The curved extension plate has a straight portion connected tangentially to one end of an arcuate portion. The arcuate portion of the extension plate approximates the shape of a theoretically ideal curve such that in cooperation with pivoting of the damper blade, the free flow area increases approximately linear with damper opening to provide a linear response between damper blade position and fluid flow rate.