Patent ID: 9695086
Date: 2017-07-04
CPC Classifications: B01D,B09B,C04B,F27D,Y02P

Claim:
1. A method of treating chlorine bypass dust in a chlorine bypass facility, the method comprising extracting a part of combustion gas, while cooling it, from a kiln exhaust gas passage, which runs from an inlet end of a cement kiln to a bottom cyclone, and recovering a chlorine bypass dust including compounds of calcium from the extracted gas, obtaining solid content by contacting a slurry including the chlorine bypass dust and a calcium compound with SO 2 gas or/and CO 2 gas, the SO 2 gas being received from a bag filter disposed between the kiln exhaust gas passage and a dissolution tank including the slurry, the CO 2 gas being exhaust gas from the cement kiln, added to the slurry via a gas introduction device separate from the kiln exhaust passage such that the SO 2 or/and CO 2 gas being added to the slurry separate from the chlorine bypass dust, and determining time for reacting the slurry containing the chlorine bypass dust to the SO 2 gas or/and the CO 2 gas by at least one selected from the group consisting of: rate of decrease in the SO 2 gas or/and the CO 2 gas when obtaining the solid content; pH of the slurry after being reacted with the SO 2 gas or/and the CO 2 gas, and chemical analysis of a concentration of calcium compounds in the chlorine bypass dust.