Solids feed nozzle for fluidized bed

Claim 1

A fuel feed system for a fluidized bed of granulated solid fuel, including, a support structure horizontally extended and perforated and arranged beneath a bed of granulated solid fuel, a bed of granulated solid fuel extended over the upper side of the support structure while being combusted, a source of combustion air connected to the under side of the support structure with the arrangement to flow the combustion air up through the perforations of the support structure at a rate and quantity which will expand the bed while it is combusting, a fuel pipe mounted to extend up through the perforated structure and terminate a predetermined distance above the perforated structure and within the expanded and combusting bed, a source of fluid-entrained granulated solid fuel connected to the fuel pipe below the support structure to flow the fuel upward and discharge from the upper end of the fuel pipe, a cap structure supported above the upper end of the fuel pipe and horizontally extended to provide its under surface as a diverter of the entraining fluid and granulated fuel to be thereby radially distributed through the expanded bed, and a sub-structure supported about the upper outlet of the fuel pipe and spaced from the under side surface of the cap to form a passage for the fuel and entraining fluid which will create a predetermined lowered pressure in the stream downstream of the passage, whereby the area of lowered pressure in the stream will cause a significant portion of the granulated solid fuel particles to flow in an elongated path through the area of combustion within the bed adjacent the fuel pipe to cause satisfactory combustion of the fuel particles.