Preparations in the nature of minerals for the treatment and purification of effluent, sewage, water and soil; reagents in the nature of minerals for the treatment and purification of effluent, sewage, water and soil; treated residues in the nature of effluent and biosolids, namely, chemical treated residues from the alumina production process for use in the purification or rehabilitation of aqueous solutions, solid and liquid wastes from mining and industry as well as treatment of acidic or ...