Recovery of raw materials is essential in our society because of the limited inventories of natural goods. Residues of firing systems also contain valuable raw materials. 32 Mio. t of these residues were accrued per year in Germany up to now, which were mostly reused in construction industry. But the residues are not specific reused at this kind of recycling and the valuable contents are accepted at best. Special applications are phosphorus recycling, fertilizer production and metal recycling. Therefore special processes are necessary, like the ATZ process, which is generally suitable for recovery of phosphorus and metals.