Abstract

As the amount of oilfield produced water (PW) keeps going up, highly efficient flotation agent is needed. In this paper, a series of surfactants (abbreviated as Q-PTEA-Cn) derived from polytriethanolamine were synthesized. Their surface activities and flotation performance were evaluated. The result showed that the Q-PTEA-Cns can effectively reduce the surface tension of water and interface tension of crude oil/water. The Q-PTEA-C12-1 had the best flotation performance and the rational flotation condition was recommended as follows: Q-PTEA-C12-1 dosage 100 mg/L, gas flow 3 L/min, and flotation time 20 minutes. At this condition, the oil removal efficiency of two commonly used flotation agents (FL-1 and FL-2) and Q-PTEA-C12-1 were 62.3%, 69.1%, and 83.6%, respectively. The flotation kinetic of Q-PTEA-C12-1 can be described by Maruyama’s flotation model, which presented that there was adsorption of oil droplet adsorbed surfactant onto bubble. Floatation mechanism study confirmed that the Q-PTEA-C12-1 can absorb onto the oil droplet and showed that the Q-PTEA-C12-1 can enhance the bubble–drop attachment efficiency and the stability of bubble–drop agglomerates.

摘要

随着油田采出水量的不断增加，需要高效的浮选剂。在本文中，合成了一系列衍生自聚三乙醇胺的表面活性剂（缩写为 Q-PTEA-Cn）。评估了它们的表面活性和浮选性能。结果表明，Q-PTEA-Cns能有效降低水的表面张力和原油/水的界面张力。Q-PTEA-C12-1的浮选性能最好，推荐的合理浮选条件为：Q-PTEA-C12-1用量100 mg/L，气体流量3 L/min，浮选时间20 min。在此条件下，两种常用浮选剂（FL-1和FL-2）和Q-PTEA-C12-1的除油效率分别为62.3%、69.1%和83.6%。Q-PTEA-C12-1的浮选动力学可以用Maruyama的浮选模型来描述，表现为油滴吸附表面活性剂到气泡上。浮选机制研究证实 Q-PTEA-C12-1 可以吸附到油滴上，并表明 Q-PTEA-C12-1 可以提高气泡滴附着效率和气泡滴团聚体的稳定性。