Author(s): Wang Dejin, Cui Zheng, University of Science and Technology of China, School of Environment Science, Anqing Normal University
Pages: 1515-1520
Year: 2014 Issue:  4
Journal: Chinese Journal of Environmental Engineering
Keyword:  cadmium wastewater; removal rate; internal circulation foam flotation tower; synergies; batch operation;
Abstract: To strengthen the efficiency of gas-liquid mass transfer,a study was carried out concerning the influence the foaming tower on the function of foam separation; therefore,an inner loop sleeve was designed to be put inside the foaming tower. The results prove that the foaming tower with inner loop sleeve has functioned much well than without through the detection and analysis of FT-IR. Through batch distillation and separation,the cadmium wastewater was put into this newly-designed foaming tower and analyzed on pH,LAS,retention period,bubble size etc. to see how these factors affect the removal rate of cadmium. The optimum treatment conditions are as follows: pH = 4. 0,LAS = 65 mg / L,the retention period of more than 20 minutes inside the tower,the gas flow of 250 mL / min. Under these optional experimental conditions,the removal rate of cadmium can reach 99. 9% when the mass concentration of cadmium is 10 mg / L. As a result of the experiment on the synergy of the surfactant, when the cationic surfactant dodecy dimethyl benzyl ammonium bromide( DDBAB) was added into the tower,a synergistic effect zone of binary surfactants was formed.