| abstract |
A wastewater clarificant very excellent in the powers for removing BOD, COD and SS is provided. The clarificant comprises an aqueous solution containing a polynuclear complex salt that is obtained by subjecting to isochoric heating an aqueous solution containing a mixture of sulfates of a plurality of metals selected from the group consisting of potassium, iron, calcium, sodium, magnesium and aluminum. Preferably, the clarificant comprises an aqueous solution containing a polynuclear complex salt that is obtained by subjecting to isochoric heating an aqueous solution containing a mixture of sulfates of a plurality of metals selected from the group consisting of, in molar concentration, 0.02 to 0.08 of potassium, 0.11 to 1.31 of iron, 0.003 to 0.030 of calcium, 0.004 to 0.040 of sodium, 0.27 to 0.81 of magnesium and 0.370 to 1.300 of aluminum. |