Patent ID: 6461153
Filing Date: 2002-10-08
Classification: B01D,C04B

Abstract:
A method for desulfurization of off-gases of a system for the manufacture of cement clinker from raw meal (10), which is preheated in a cyclone suspension heat exchanger system (11) by the off-gas (27) of a rotary kiln (19), calcined in a tubular precalcination stage (16), and burned to cement clinker in the sinter zone of the rotary kiln (19) and subsequently cooled in a downstream clinker cooler (20), the off-gas (27) of the rotary kiln (19) being used in said tubular precalcination stage (16), where fuel is added for calcination of the raw meal and having a mixing chamber (29) in the flow deflection region of the precalcination stage between an ascending pipeline branch and a descending pipeline branch, for separation of oversize material (30) from a gas-solid suspension in order to promote residual fuel burnout, including the step of:combining at least one substream of said oversize material (30) exiting said mixing chamber (29) of said precalcination stage (16) with off-gas (22) discharged from the cyclone suspension heat exchanger system (11) as a solid sorbent to convert the sulfur oxides contained in said off-gas (22) to calcium sulfate (34), and separating said calcium sulfate from said off-gas (22).