超稠油油藏溶剂辅助蒸汽重力泄油室内实验研究

以国内某超稠油油藏为基础，应用二维物理模拟装置开展了蒸汽辅助重力泄油(SAGD)对比实验，研究了溶剂辅助SAGD技术对SAGD蒸汽腔发育特征、原油产量以及采收率的影响。研究结果表明，溶剂辅助SAGD中，溶剂以液相和气相共同存于油藏中，溶剂浓度越高，气相组分含量越高；溶剂中的气相组分在油藏中可以减少蒸汽在上覆岩层的热损失，提高蒸汽腔垂向扩展均匀性；合理溶剂浓度下，溶剂辅助SAGD可以显著提高峰值产量；低浓度溶剂辅助SAGD的单位原油产量的能耗明显低于纯蒸汽SAGD。实验结果表明，低浓度溶剂辅助SAGD对于开采超稠油油藏具有较大的应用潜力。

Experimental Study on the Solvent Assisted Steam Gravity Drainage Process in Extra heavy Oil Reservoirs

Based on an extra heavy oil reservoir in China, experiments of Steam Assisted Gravity Drainage (SAGD) were carried out with a two dimensional apparatus. We present new findings on the effects of solvents on the characteristics of steam chamber development, production rate and oil recovery. Our results show that liquid and gaseous components in the solvent co exist in the oil reservoir. The mass quantity of the gaseous components was higher when higher concentration of solvent was injected. The gaseous components in the reservoir are accumulated in the top of the reservoir, reducing the heat loss and improving the conformity of the steam chamber shape in the vertical plane. Solvent assisted SAGD has greatly improved the peak oil rate with proper concentration. Energy consumption per unit oil production in the low concentration solvent assisted SAGD process is significantly lower than that in the pure SAGD process. This study shows that solvent assisted SAGD has great potential in recovering extra heavy oil reservoirs.