乳状含柴油水体柱浮选分离工艺研究

Separation of Diesel from Oil-Containing Water Emulsion by Flotation Column Processes

以超声波乳化制得的乳状含柴油水体作为模型实验原料,采用柱浮选工艺实现油水分离。考察了阳离子度和加入量、进料位置、液体流量、气体流量等因素对除油率的影响,基于浮选因素对除油率影响的实验结果初步探讨了浮选机理。通过探索浮选因素得出最佳操作条件:进料位置为上部、进料流量为10 L?h?1、气体流量为0.25 Nm3?h?1、阳离子度为92的PDA加入量为5 mg?L?1,此时除油率可达68.08%;此外,除油率随PDA阳离子浓度的增加呈现先增加后减小的趋势。通过分析浮选机理发现,气泡和絮凝体接触时间越长、接触机会越多,除油率越高,且浮选时气泡和絮凝体之间的碰撞、附着和分离过程影响除油率,只有当两者大小接近时,才能形成稳定的带气絮体,从而实现油水分离。

Diesel containing water emulsion produced by ultrasonication was used as an example to study oil separation performance of a flotation column process. The effect of PDA cationic degree and dosage, liquid flow rate, feed position and air flow rate on oil removal efficiency was explored, and the flotation mechanism was investigated. Experimental results show that when the PDA cationic degreeand dosage are 92 and 5 mg·L^-1, respectively, the liquid flow rate from the top feed position is 10 L·h^-1 and the air flow rate is 0.25 Nm^3·h^-1, and the oil removal rate can reach to 68.08%. Moreover, with the increase of PDA cationic concentration, the oil removal rate increases first and then decreases. The results also indicate that longer contact time between bubbles and floes can lead to higher oil removal rate. The oil removal rate was determined by interaction and separation between bubbles and floes.The oil removal rate was higher when bubbles and floes have similar sizes, which forms aerated floes.