| 摘要 |
Cleaning or scrubbing of SO2-containing flue gas from a circulating fluidized bed furnace containing a particulate SO2 sorption agent is such that some of the unreacted agent is hydrated and recycled for high temperature reactivation. Cleaning or scrubbing of SO2-containing flue gas from a circulating fluidized bed furnace which uses S-containing coal with an air feed at 700-950 degrees C and which has a particulate SO2 sorption agent comprises (i) feeding a part of the ash, a part of the sorbent/SO2 reaction product and a part of the unreacted sorbent from the combustion chamber to a mixer; (ii) adding water or an aqueous Na-containing solution and mixing so that the unreacted sorbent is hydrated at 60-100 degrees C and atmospheric pressure; (iii) recycling the ash together with the reaction- and hydration-products back into the combustion chamber; and (iv) reactivating the hydration product at 700-950 degrees C to give an SO2-sorption agent. Also included is an Independent claim for the process comprising a combustion chamber (2), a device for removing the ash, sorbent reaction product and unreacted sorbent from chamber (2), a mechanical mixer (12) and a recycling device. |
