超稠油掺稀油开采实验及数值模拟研究

蒸汽吞吐是增加稠油产量的一种经济而有效的方法，但该方法存在热损失大等问题，使注汽效果达不到预期的目的。采用在注蒸汽过程中向地层掺入稀油的方法来降低地层稠油的粘度，实验研究了超稠油掺稀油后粘度的变化，并按非线性混合方法计算了稠油与稀油混合后的粘度。通过数值模拟，考察了掺稀油的注入量、注入方式、注入时机、注稀油后的生产时间等参数对开发效果的影响。结果表明，在掺稀油开发超稠油的过程中，焖井结束后可适当延长生产时间，以增加周期产油量；掺稀油的最佳注入时机应选在第3或第4周期开始；周期注入稀油的量为10-15m^3，在此范围内，换油率较大；稀油的注入方式按2-3个段塞注入比较合适。注汽过程中掺稀油的方法可在很大程度上改善超稠油的开发效果。

Study of experiment and numerical simulation of superheavy oil production by mixing light oil

Steam huff and puff is a kind of economic and effective method for improving heavy oil production, but the production effect cant reach the expected purpose because of heat energy loss. The change of superheavy oil viscosity after mixing light oil was studied by the experiment, and the mixed viscosity was calculated by non-linear mixing method. The effects of parameters including injection volume, injection strategy, injection opportunity of light oil and production time on development effect were investigated by numerical simulation method. The results show that after mixing light oil, the production time can be prolonged to add cycle production, and the light oil should be injected at the begining of the third or fourth cycle. The injection volume of light oil ranges from 10 to 15 m^3 in each cycle becouse of oil change ratio with larger value in this range, and light oil should be injected by 2- 3 slugs. During steam huff and puff, the development effect of heavy oil reservoir can be improved by viscosity reduction of heavy oil through mixing light oil in reservoir.