Experimental Analyses of Athabasca Bitumen Properties and Field Scale Numerical Simulation Study of Effective Parameters on SAGD Performance

摘要

Due to reduction of high quality oil resources and consequently increase of oil price around the world, new sources of energy should be find to relief the high demand of energy. Hence, countries like Venezuela, United States and particularly Canada came up with their unconventional reservoirs which contain bitumen, extra heavy oil and heavy oilas remarkable sources of energy. Exploitation of such kind of reservoirs was not beneficial in the past but in recent years due to the increase of oil price tendency to production from heavy oil reservoirs has incredibly increased. This paper introduces experimental measurement of Athabasca heavy crude oil properties and simulation study in a field conditions. The first-hand target of the performed study isto scrutinize and evaluate the performance and capability of steam-assisted gravity drainage (SAGD) process which is the greatest applicable thermal processes in tar sand reservoirs. The results show great recovery of heavy oil and reasonable amount of cumulative steam-oil ratio (CSOR). Sensitivity analyses have been done to realize the influence of different parameters on proficiencyof SAGD in the field. The significance of parameters such as permeability both in horizontal and vertical direction, horizontal and vertical shale barriers, injection rate, porosity, injector location, viscosity, preheating period, horizontal well length and steam quality were studied. Higher vertical and horizontal permeability, injection rate and steam quality have positive effect on oil production while Lower porosity, absence of preheating period and higher injection rate have adverse effects on SOR. Preheating period has impact on SOR at the start of the process. In fact without preheating period the amount of SOR at the start of process is very high. Horizontal shale barrier has more negative effect on oil production than vertical shale barriers. Locating injector close to the horizontal production well has nugatory impact. The shorter the length of horizontal wells the lower the recovery of oil. This work explains the aforementioned effects in details.