摘要 |
A process for the simultaneous scrubbing of exhaust gases and recovery of residual heat from a combustion plant (1) uses two reactors A, B (4, 5) arranged in parallel. As the gas passes through a reactive layer (8) in reactor A (4) it gets scrubbed and also releases residual heat as it becomes cooled to below its dew point. At the same time air used for combustion is passed in the opposite direction to the exhaust gas through reactor B (5) in order for it to cool the reactor and to remove condensate, following which the air is passed through heat exchangers (9,10) to cool it in order to remove condensate and then re-heat before it is supplied to the combustion plant. Periodically the flow of exhaust gas and combustion air are switched to the other reactor. Preferably the reactive layer comprises limestone. The apparatus used for this process is also claimed, in which the two reactors contain lime material scrubber beds, the first reactor A being used to remove sulphur oxides, hydrogen chloride and fly ash from the exhaust gas whilst combustion air is passed through the second reactor B in the opposite direction to cool the scrubber beds and remove condensate. Switching over the beds is carried out at intervals regulated by temperature of the scrubber beds. |