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.%工业生产中会产生大量结构稳定的含油废水，将环流的概念引入传统的空桶式柱气浮工艺来处理含油水体，以克服空桶式浮选柱液体停留时间短、碰撞效率低的缺点，达到提高油水分离效果、深度净化水体的目的。实验中以超声乳化柴油水溶液作为原料，优选出适合本体系的气浮药剂二甲基二烯丙基氯化铵/丙烯酰胺共聚物（PDA），考察了环流气浮法中各工艺条件的影响。结果表明，当气体流量为250 L·h−1，液体流量为10 L·h−1，液位高度为6 cm，PDA用量为20 mg·L−1时，气浮效果最好，最高除油率可达90.48%。对比相同工艺条件下的空桶式柱气浮法，除油效率提高了10%以上，且气浮速度更快，具有很高的工业应用价值。
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