INTEGRATED SYSTEM FOR REACTIVATING AND RECIRCULATING LIGHT ASHES WITH HIGH UNBURNT MATTER CONTENT

摘要

The present invention relates to a treatment for reactivating light ashes, obtained from the combustion of fossil fuels or from the co-combustion therewith of CDR or biomasses inside dust phase boilers. The light ashes conveyed by the combustion fumes and kept by electrostatic precipitators or by baghouse filters are extracted therefrom and sent to the integrated system allowing the reactivation thereof with respect to the post-combustion, before being made to recirculate in the combustion chamber through the boiler burners. Said reactivation treatment of the ashes is obtained by making them to transit inside an accumulation system in contact with air at a suitable temperature and for a determined time period, so as to obtain the chemisorption of the oxygen available in the gaseous current by the carbon of the unburnt portion. The integrated system allows reducing the percentage of unburnt matter in the light ashes and transforming them from waste into raw material which can be re-used in the cement and concrete industry.