Abstract: An apparatus and process for removing sulphur components from flue gasses which include O.sub.2 and water vapor. The flue gasses are first heated to at least 1000.degree. F. Then H.sub.2 is added to the flue gasses for converting at least some of the SO.sub.x components to S and H.sub.2 S. H.sub.2 O is then sprayed into the flue gasses for precipitating particulate matter and for converting at least some of the H.sub.2 S components into H.sub.2 SO.sub.4. The resultant flue gasses are then filtered through lime rock for absorbing any H.sub.2 S and H.sub.2 SO.sub.4 components and for trapping any remaining particulate matter therein. Some of the NO.sub.x components may also be reduced using this process. An apparatus for effecting this process is also disclosed.