MERCURY RECOVERY SYSTEM AND RECOVERY METHOD FROM CEMENT KILN DUST

摘要

PROBLEM TO BE SOLVED: To efficiently recover mercury from a dust contained in a cement kiln combustion exhaust gas at a low cost.SOLUTION: A mercury recovery system 1 from a cement kiln dust is equipped with a mixing device 2 for heating a cement kiln dust KD by a sensible heat of a duct for heating with mixing with a high temperature dust (dust for heating) HD, and a mercury recovery device 7 for recovering mercury vaporized by mixing heating. A vibration fluidized bed type classifying machine 3 for fluidizing a mixture M of the cement kiln dust and the dust for heating, and separating a coarse powder D1 and a gas G1 containing a coarse powder D2 can be arranged after the mixing device and mercury contained in the gas containing the coarse powder separated by the vibration fluidized bed type classifying machine is recovered with the mercury recovery system. The dust for heating can be a cement raw material fractionated from a pre-heater of a cement firing device and/or a coarse powder of a chlorine bypass dust.