Revasol

VALORISATION OF ALL THE FLUE GAS CLEANING RESIDUES: THE NEUTREC^® PROCESS.

SOLVAY has patented a technology developed by the ULB (Free University of Brussels), which combines processing of the RSC (residual sodium chemicals) with that of the fly ash. In the longer term this will offer incinerator operators both a global solution to their waste problems (fly ash and RSC) and the ability to recycle almost all the residual chemicals from flue gas cleaning.

The fly ash is washed and passes over a belt filter.

The filtration cake is chemically stabilised and then processed thermally to produce a matter which is free of dioxins and furans. Laboratory studies are under way to define potential applications for this solid, in construction and/or public works.

The fly ash washing water is re-used as dissolving water in the RSC cleaning process.

Globally, this system permits recycling of all the soluble salts in the fly ash and the RSCs, and also of a very large portion of the insolubles themselves. This reduces the final waste from the dedusting and flue gas neutralisation processes to under 4 kg per ton of municipal waste.

This process is currently being evaluated as part of a pilot project co-financed by ADEME. Initial results will be available by around 2003.

Other possibilities:

Direct recycling of flue gas cleaning residues (single filtration). 

Recycling of Residual Sodium Chemicals in the production of sodium carbonate (double filtration).

Recycling of Residual Sodium Chemicals in the manufacturing of sodium carbonate (single filtration).