加拿大SAGD油砂乳状液掺稀脱水实验

Experiment on dehydration of Canada SAGD oil sand emulsion through mixing with diluent

为优化加拿大SAGD油砂乳状液脱水处理工艺,研究了加拿大SAGD油砂样本物性,理论分析了SAGD油砂乳状液的稳定性,开展两种典型稀释剂的稀释特性实验,获得了各自的稀释脱水特性,为脱水处理工艺的完善与优化提供指导。研究结果表明,以石脑油为代表的芳香族稀释溶剂的经济技术掺稀比为20%,石脑油掺稀降黏增大密度差的效果较好,但是对于水滴聚结的作用效果不明显,造成整体脱水效果较差,因此实际应用时仍需要加破乳剂。而以正庚烷为代表的脂肪族溶剂由于黏度、密度比石脑油大,因此降黏效果较差,但在超过一定比例后,能使SAGD油砂乳状液中的沥青质沉积,稀释特性表现为从掺稀降黏作用转变为沥青质沉积,掺稀比为1.8时可以完全脱除油砂乳状液中的水滴。

To optimize dehydration process of Canada SAGD oil sand emulsion, experiment was made on physical properties of Canada SAGD oil sand samples, and theoretical analysis was made on stability of SAGD oil sand emulsion. In the experiment, two typical diluents were used to identify their respective behaviors in dilution dehydration, providing direction for the perfection and optimization of dehydration process. The experimental results show that the economictechnical ratio of aromatic diluting solvent represented by naphtha is 20%; although the naphtha has good effect on reducing viscosity and increasing differential density, its effect on waterdrop coalescene is unobvious, resulting in poor dehydration effect, therefore, demulsifi er is still needed in practical application. In contrast, the aliphatic solvent represented by normal heptanes, with higher viscosity and density than naphtha, has less effect on viscosity reduction; however, when exceeding a certain proportion, it can make the asphaltene in SAGD oil sand emulsion deposit, with dilution characteristics converted from viscosity reduction into asphaltene sedimentation. The experimental results show that, when the diluent ratio reaches 1.8, the waterdrop in oil sand emulsion can be completely removed.