Economic Optimization for Operation Conditions of Single-Well SAGD in Thin Bitumen Reservoirs
Van Xuan Tran2, Thuong San Ngo2, Huy X. Nguyen1, Bae Wisup1, Min Sung1, D. Y. Kim1
1 Department of Energy Resources, Sejong University, Seoul, Korea, Republic of.
2 Ho Chi Minh City University of Technology, Ho Chi Minh City, Viet Nam
The steam assisted gravity drainage (SAGD) process is an effective thermal method for heavy oil and bitumen production in Western Canada. However, SAGD process only has conducted successfully for a minimum thickness of 15m, while most of the smaller thickness proved to be uneconomical for using SAGD well pairs in actual field cases. Single-well (SW) SAGD is the best choice of operating process for thin heavy oil reservoirs. Economic issues of SW-SAGD are still questionable associated with high capital investment, operating costs, and uncertainties of oil and gas prices, while previous studies were only interested in technical solutions. The integration of economic and technical aspects for SAGD performance is essential in practice.
This paper presents design of experiment and response surface methodology to find the best operating conditions with high confidence level for the prediction of SW-SAGD performance. Then, discontinuous SW-SAGD technique was operated as cyclic steam injection to control the amount of steam injected at several specific time intervals. The results showed that heat losses were minimized, increasing cumulative oil and economic efficiency, which led to the NPV higher than other methods. The results of this study can applied successful broadly in thin oilsands reservoirs.
AAPG Search and Discovery Article #90155©2012 AAPG International Conference & Exhibition, Singapore, 16-19 September 2012