摘要
针对海上稠油开采出现的问题,国内发展了注多元热流体吞吐热力采油技术。与蒸汽热力采油相比,多元热流体可以显著降低稠油黏度、增加油层压力,提高开采效率。本文基于实际气体状态方程和混合法则建立注多元热流体内部流动与传热模型,并与注蒸汽井筒流动与传热状态进行对比,详细对比两种热采介质在井筒流动与传热情况。通过研究发现:在井筒注入相同温度与相同注入速率的多元热流体与饱和蒸汽,多元热流体井筒压力和温度下降速度更快,到达井底时压力更大,温度更低,与地层和油层的温差更小,井筒热损失更少,但是热量含量低,油层加热范围小。要想达到与蒸汽一样加热效果,可以增加多元热流体注入速率和注入温度。同时由于CO_2和N_2作用,油层温度分布更加均匀,热量更多,油层加热范围更大,注多元热流体开采效果更好。
For solving the problems of offshore heavy oil exploitation,researchers developed the multiple thermal fluid thermal recovery technology.Compared with steam,multiple thermal fluids can significantly reduce the viscosity of heavy oil and increase the reservoir pressure,improve the mining efficiency.Based on real gas state equation and mixed rules,the model for flow and heat transfer of multiple thermal fluids is established to compare with flow and heat transfer of steam injected in wellbore,detailed conditions of two kinds of thermal medium in wellbore are analyzed.The results show：compared with steam under the same injection temperature and rate injected in wellbore,pressure and temperature of the multiple thermal fluid wellbore drop faster.Bottom hole pressure is larger and temperature is lower when it reaches wellbore bottom,and the temperature difference between formation and reservoir is smaller,heat loss is less,but heat is lower,oil heating range is smaller.To achieve the same heating effect with steam,it need increase injection rate and injection temperature of the multiple thermal fluids.At the same time,due to the effect of CO_2 and N_2,reservoir temperature distribution is more uniform,and more heat is injected into reservoir,so heat range of oil is bigger,the multiple thermal fluid extraction effect is better.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2016年第9期1867-1874,共8页
Journal of Engineering Thermophysics
基金
国家自然科学基金项目(No.51176182)
关键词
井筒
散热
蒸汽
多元热流体
实际气体
wellbore
heat transfer
steam
multiple-thermal fluid
actual gas
