Abstract：Using a homemade inner circulating foam fractionation column, simulated wastewater containing Cr ion was treated and compared with a conventional bubble tower in its separation efficiency, and the influential factors pH value, Fe(NO3)3, concentration of sodium dodecyl sulfate (SDS), gas flow and separation time were examined. The results show that the circulating flotation column separation efficiency is higher within 12 to 35 min, Cr ion concentration reaches 0.6 mg/L in the fractionation in 35 min, but 10 mg/L in the conventional bubble column. The optimum operating conditions of inner loop flotation column are obtained, for the initial Cr ion concentration of 20 mg/L in waste water, under pH 5.5, SDS 100 mg/L, Fe(NO3)3 60 mg/L, and gas flow rate of 800 mL/min, the treatment effect is preferable. The bubble entrainment rate is about 10%, and Cr(III) removal rate over 97%.
2013, Vol. 13 
