Characteristics and application of waste residue from the synthetic rutile industry in the treatment of wastewater

A series of experiments were conducted to characterise neutralized acid residue from the synthetic rutile industry. Column sorption experiments were conducted to investigate the attenuation of DOC and nutrients in wastewater using neutralized acid residue. After 145 days, DOC, TP, PO4-P, TN, NH3-N, NOx-N and DON in neutralized acid residue/sand column effluent were reduced by 88.9%, 94.9%, 99.1%, 63.5%, -107.3%, 71.2% and 77.7%. DOC, TP, PO4-P, TN, NH3-N, NOx-N and DON in sand column effluent were reduced by -0.3%, -50.1%, -44.8%, -10.8%, -298.2%, 86.3% and -28.5%. The calculated removal rate of DOC, TP, PO4-P, TN, NH3-N, NOx-N and DON by neutralized acid residue are 88.9%, 96.6%, 99.4%, 67.1%, 47.9%, -110.1% and 82.7%. Neutralized acid residue exhibits good sorption of DOC and nutrients. Neutralized acid residue may be of benefit in reducing water pollution