Numerical Simulation Study on Flue Gas-Assisted Steam Huff and Puff in Heavy Oil Reservoirs

In response to challenges such as the rapid rise of water content, the rapid decline of periodic production, and the serious intrusion of edge and bottom water in heavy oil reservoirs after multicycle profile control, the flue gas-assisted steam huff and puff technology is proposed. By focusing on Block Cao128 in the L Oilfield as a research subject, the feasibility of applying the flue gas-assisted steam huff and puff technology in heavy oil reservoirs has been verified through the establishment of a three-dimensional geological model. Additionally, the injection and production parameters in steam huff and puff have been optimized. The research results indicate that when the cyclic steam injection volume is 1000 t, the maximum net oil increment can be achieved, reaching 6308 × 10⁴ t. Furthermore, when the cyclic flue gas injection volume is 9 × 10⁴ Nm³, the efficacy of the flue gas-assisted steam huff and puff is enhanced. The optimal injection method is to inject flue gas in the early stage of steam huff and puff, and the oil-gas ratio is increased to 1.77. The introduction of flue gas can enhance production significantly and exert a significant impact on early-stage production. The earlier the injection time of flue gas, the better the development effect. Flue gas-assisted steam huff and puff technology improves energy utilization efficiency and reduces pollutant emission. It has a significant positive impact on environmental protection and sustainable development.