As an efficient and clean oil removal process technology,dissolved air flotation is commonly used in the similar density between liquid-liquid two-phase flow or the separation of suspended particles in water.As the places of generation of the micro bubbles and the adhesion between micro bubbles and oil droplets and suspended material,the contact zone which has a great effect on size of the micro bubble distribution and gas content has an important influence on the oil removal efficiency.Experiments show that bubble size is smaller at 0.34 MPa;double nozzles can significantly increase the rate of gas content;turbulent motion strengthens the bubble coalescence with the smaller contact zone;surfactant concentration can reduce the surface tension,and restrain the micro-bubble coalescence;the optimal concentration was 0.5％ with the average size at 65 ～70 μm.%气浮技术作为高效清洁的除油工艺,常用于密度相近的液-液两相流或水中悬浮颗粒的分离.作为微气泡的产生及微气泡与油滴等悬浮物质黏附的场所,气浮池接触区水利流动状态下的微气泡粒径及气含率分布对除油效率有着重要影响.实验表明,溶气压力0.34 MPa时微气泡尺寸更小;双释放头能显著提高气含率;接触区宽度较小时,湍动作用加强微气泡聚并严重;表面活性剂浓度能降低表面张力,有效抑制微气泡聚并;最佳浓度为0.5 mg/L时,平均尺寸维持在65 ～70 μm.
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