关键词: 浮选, 环流浮选柱, 分离, 废水, 工艺条件

Abstract:

Significant amounts of oil-containing waste water are discharged in industrial processes, and it is difficult to separate the oil/water mixture. In this paper, a concept of air-lift loop was introduced to traditional flotation process to treat oil-containing water. In the experiment, oil-in-water emulsion was produced by ultrasound, and the flotation agent for this system was optimized first, as poly(acrylamide-co-diallyldimethyl ammonium chloride) (PDA). Then, the effect of different conditions in the loop flotation process was investigated. When air flow rate was 250 L·h^-1, liquid flow rate was 10 L·h^-1, liquid level was 6 cm, amount of PDA was 20 mg·L^-1, oil removal rate was the highest. Concentration of oil was reduced from 900 mg·L^-1 to 100 mg·L^-1 and the highest efficiency was 90.48%. Compared with the traditional column flotation under the same condition, loop flotation was more effective and quick, with increased oil removal by 10%. The loop flotation concept would have great industrial application value.

Key words: flotation, air-lift loop column, separation, waste water, technological conditions