Method and device for separating gaseous pollutants from hot process gases by absorption and a mixer for moistening particulate dust

摘要

In a method of separating gaseous pollutants from hot process gases, the process gases are passed through a contact reactor ( 22 ), in which an absorbent material in a moistened state is introduced to convert the gaseous pollutants into separable dust. The dust is separated in a dust separator ( 10 ). The separated dust is cooled in a first step by being brought into direct contact with a cooling fluid. In a second step, the cooled dust is mixed with a gas containing water vapour, said gas having a saturation temperature that is higher than the temperature of the cooled dust. The dust moistened by condensation of the water vapour is introduced into the contact reactor ( 22 ) to be mixed with the process gases. A mixer ( 24 ) for moistening of absorbent material has a first end ( 26 ) and a second end ( 28 ) and is divided into two zones. A first zone is a cooling zone ( 68 ) located at the first end ( 26 ). A second zone is a moistening zone ( 80 ) located at the second end ( 28 ).