Fluidized bed reactor method and apparatus

In a fluidized bed reactor having a grid provided with a plurality of nozzles by which combustion and fluidization air is evenly distributed from an air chamber disposed below the grid to a fluidization zone above the grid, and wherein the grid is provided with an outlet opening for coarse material, the improvement comprising:

• at least one discharge device including a vertical pipe portion connected at one end to said outlet opening and at the other end to an aeration chamber extending angularly with respect to said vertical pipe portion substantially equally in two opposite directions;
• said aeration chamber provided at a lowermost end with means for supplying intermittent and substantially instantaneous blasts of air into said aeration chamber, and at an uppermost end with a discharge opening which opens into said air chamber, each said blast substantially emptying said coarse material from said aeration chamber.

A method for discharging coarse material from a fluidized bed reactor having a grip provided with a plurality of nozzles by which combustion and fluidization air is evenly distributed from an air chamber disposed below the grid to a fluidization zone above the grid, and wherein the grid is provided with an outlet opening for coarse material, comprising the steps of:

• (a) providing at least one discharge device including a vertical pipe portion connected at one end to said outlet opening, and at the other end to an aeration chamber extending angularly with respect to said vertical pipe portion, said aeration chamber provided at one end with a discharge opening, and at an opposite end with means for supplying pressurized air into said aeration chamber;
• (b) periodically supplying pressurized air in the form of substantially instantaneous blasts into said aeration chamber to discharge substantially all of the coarse material in the aeration chamber from the reactor with each blast, and wherein each said blast of air is supplied at about 2.5-7.0 bar.