Abstract: A fluidized bed combustion apparatus, system and process in which the turbulent fluidized motion is imparted to the particles to be burned by mechanical means. The bed of combustible material may be fluidized on a fluidizing support screen which is vibrated by a motor drive. The fluidizing force may be directed so that, in addition to fluidizing the bed, it slowly moves the particles from a feed end of the bed to an ash or waste disposal end of the bed with combustion taking place during the travel from one end of the bed to the other. The degree of fluidization can be controlled by a master combustion control system. The air necessary to support combustion may be controlled by an inlet damper or by a variable speed combustion air fan controlled by an inlet damper or by a variable speed combustion air fan controlled by the master combustion control system as a ratio of the fuel input rate or desired firing rate. Stack gas analysis may be used to trim the combustion control system.