Numerical Study on Viscosity Reduction in Mining Heavy Oil by Circulating Hot Water

Viscosity reduction is an important process in mining heavy oil.To predict the temperature variation and viscosity variation of heavy oil in flow direction,computational fluid dynamics(CFD) was adopted to simulate the process of heat transfer and flow in this paper.Moreover,an objective function,namely viscosity reduction efficiency,was established to analyze the effect of viscosity reduction.The results indicate that circulating hot water can reduce viscosity significantly,and that the effect of viscosity reduction depends on the inlet temperature and inlet volumetric flow rate of hot water.There is a maximum temperature of heavy oil in flow direction.With the inlet volumetric flow rate of 2.0m3/h and the inlet temperatures of 60,℃,70,℃ and 80,℃,viscosity reduction efficiencies are 94.6%,96.7% and 97.3%,respectively.With the inlet temperature of 70,℃ and the volumetric flow rates of 1.5m3 /h,2.0 m3/h and 2.5m3/h,viscosity reduction efficiencies are 94.4%,96.7% and 97.2%,respectively.

真空绝热油管∶项目实例及应用

真空绝热油管首先在美国阿拉斯加投入使用 ,其目的是在热油开采过程中确保永冻层不被融化。到 2 0世纪 80年代早期 ,这种油管广泛用于提高采收率法采油(EOR) ,用于开采美国加利福尼亚州Bakersfield的重油 ,以及加拿大阿尔伯塔省北部的重质沥青砂。这些早期的EOR方案目前用在海洋完井过程中防蜡和避免形成水化物。1995年 ,DiamondPower公司率先在美国墨西哥湾将真空绝热油管用在海底完井中。DiamondPower公司已对一种真空绝热油管的“管中管”设计申请了专利 (美国专利号4 ,512 ,72 1) ,两管之间的环形空间抽成了真空。这种油管与EOR蒸汽采油法一道用于井下及海底完井中。