Ferric Alum Slab Supplier In Chennai Ferric Alum Slab Supplier Near By #Chennai #Poonamalle #Ambattur #Tambaram #Tamilnadu Ferric alum slabs (typically 20 kg to 25 kg solid blocks of aluminum sulfate containing iron) are primarily used as a cost-effective coagulant in water purification, sewage treatment, and industrial manufacturing. The solid slabs are dissolved in water to create a dosing solution or applied directly into large-scale treatment basins.