In the treatment of REA gypsum and fly ash, filtration solutions from BHS-Sonthofen ensure a particularly high quality of the respective end product. The use of appropriately treated materials conserves resources and thus helps to protect the environment.
In flue gas desulfurization (FGD) by means of the lime washing process, gypsum is produced in large quantities as a by-product. Strict quality criteria apply so that FGD gypsum can be used as a full substitute for natural gypsum. The gypsum is washed on indexing belt filters from BHS (indexing belt filter or rubber belt filter) to reduce the chloride pollution to less than 100 ppm. This is followed by drying the material to a residual moisture of less than ten percent. The quality of the building material processed in this way is in no way inferior to that of natural gypsum.
Fly ash from waste incineration plants contains large quantities of heavy metals. Vacuum belt filters from BHS (indexing belt filters or rubber belt filters) remove most of the heavy metals and chlorides. The remaining solid material is washed and set with cement. The resulting cement/fly ash mixture is proven not to release any heavy metals. This makes the mixture a product that can be used as a building material.