FAST FLUIDIZED BED REACTOR AND METHOD OF OPERATING THE REACTOR

摘要

A method of operating a fast fluidized bed reactor according to the invention comprises: (1) providing a fluidized bed reactor containing a bed of granular material and having an upper and a lower region, the upper region having a cylindrically shaped interior surface and a cylindrically shaped exit throat aligned concentrically with the interior surface, the exit throat having a smaller diameter than that of the interior surface; (2) feeding matter to be reacted into the lower region of the reactor; (3) supplying a first stream of pressurized air to the reactor through a plurality of openings in the lower region at a sufficient velocity to fluidize the granular material in the circulating regime, whereby at least a portion of the granular material is continually entrained into the upper region; (4) tangentially supplying a second stream of pressurized air to the upper region of the reactor through at least one opening in the cylindrical interior surface of the upper region wherein, at maximum operating capacity for the reactor, the second stream of air constitutes in excess of about 50% of the total pressurized air fed to the reactor (5) maintaining a Swirl number of at least about 0.6 and a Reynolds number of at least about 18,000 in the upper region of the reactor for providing a cyclone of turbulence in the upper region which increases the rate of reaction in the reactor and creates at least one reverse flow zone in the upper region for returning at least a portion of the granular material to the lower region of the reactor; and (6) permitting the reaction gases in the upper region to exit from the reactor through the exit throat, while retaining substantially all of the granular material within the reactor. In accordance with the invention, cyclone particle separators are not required. Apparatus suitable for use in practicing the aboverecited method are also disclosed.