Open Access
ARTICLE
Feasibility Research of Steam-Assisted-Gravity-Drainage Process in Bohai Offshore Heavy Oil Reservoirs
Xiaohu Dong1, Huiqing Liu1, Xiaohong Liu2, Zhennan Gao2
1 MOE Key Laboratory of Petroleum Engineering in China University of Petroleum, Beijing, China.
2 Exploration and Development Research Institute of Tianjin Branch CNOOC, Tianjin, China.
Structural Longevity 2013, 9(3), 197-205. https://doi.org/10.3970/sl.2013.009.197
Abstract
The LD5-2N block is a typical heavy oil reservoir in Bohai offshore
oilfield, and the viscosity of crude oil for this block at reservoir condition is about
10000mPa.s. Therefore, the conventional exploitation method of water flooding
or chemical flooding will be not suitable for this block, and the thermal recovery
should be considered. Using the method of numerical simulation, the steam assisted
gravity drainage (SAGD) process for this block is investigated in this paper. Firstly,
a sensitivity analysis process of reservoir properties and fluid parameters is conducted, e.g., reservoir thickness, oil viscosity, permeability, the vertical-horizontal
permeability ratio etc. Then, on account of the shale cases in this block, an orthogonal test is carried out to study the influences of shale barriers on SAGD process.
Results indicate that the parameters of reservoir thickness, reservoir permeability
have a significantly influence on the recovery rate of SAGD process. For a SAGD
process, the reservoir thickness should be greater than 20m. With the increase of
vertical permeability, the expanding rate of steam chamber is on a rise, and thus
the recovery rate of SAGD process is increased. The bottom water will reduce the
oil recovery by about 10∼20%. Furthermore, the existence of shale barrier also
has a tremendously influence on the drainage process, especially for the recovery
rate. This investigation could be used for the application of SAGD technique in the
similar heavy oil reservoirs.
Cite This Article
Dong, X., Liu, H., Liu, X., Gao, Z. (2013). Feasibility Research of Steam-Assisted-Gravity-Drainage Process in Bohai Offshore Heavy Oil Reservoirs.
Structural Longevity, 9(3), 197–205. https://doi.org/10.3970/sl.2013.009.197