Process for producing a desired redox potential for flue gas scrubbing by utilising a liquid metal granule-fluidised bed reactor technique

摘要

It is known that for the simultaneous separating out of SO2 and NOx from flue gases, the redox potential must be moved in a controlled manner in the negative range. Additives, such as sodium dithionite, are employed for adjusting the liquid. It is further known to control the redox potential electrolytically and/or by means of an iron reactor. In order to ensure a high availability of flue gas desulphurisation plants, according to the invention it is proposed that metal granule spheres are added to the scrubbing liquid in the direct scrubber sump or in a by-pass and the scrubbing liquid is passed through a fluidised-bed reactor technique in which the iron granules take on the task of controlling the redox potential. The housing of the fluidised-bed reactor can be composed of an insulated vessel, so that the mixture of liquid and metal granules can be electrolytically controlled as a fluidised bed.