冀东X油藏型储气库建库及提高原油采收率方案优化研究OA

Underground gas storage(UGS)facilities in China are predominantly developed in gas reservoirs,exhibiting lim-ited diversity,while UGS conversion from depleted oil reservoirs remains in its nascent stage.To address key challenges such as complex post-waterflood fluid distribution,intricate seepage mechanisms,and undefined technical policies for synergistic development,this study focuses on the X Oil Reservoir in the Jidong Oilfield.A comprehensive investigation was conducted to optimize collaborative hydrocarbon recovery enhancement and storage capacity expansion.By integrating high-resolution geological characterization,dynamic evaluation of individual well injectivity/productivity,and optimal well pattern selection,a numerical simulation model was established.Quantitative analyses were performed to evaluate the impacts of full-cycle liquid drainage,timing of transitioning to areal flooding,and staged pressure ramp-up on storage capacity utilization and oil recovery.The results are as follows:1)Full-cycle liquid drainage significantly enhances drainage rates and working gas volume compared to conventional methods;2)The optimal transition to areal flooding occurs when the gas front reaches the structural low,effec-tively mitigating gas breakthrough risks while accelerating working gas formation;3)A"staged and stepwise pressure ramp-up"strategy is proposed,with the initial pressure increase timed at the shift from single-pattern gas drive to areal flooding,enabling synchronous growth in both storage capacity and drained liquids.Simulation forecasts indicate that the"full-cycle drainage+pressure ramp-up"mode will achieve the target working gas volume of 10.52×108 m3 by 2034-2035,maximizing both storage space and recovery efficiency.These results provide critical technical foundations for realizing the"high deliverability with fewer wells and efficient UGS development"objective in similar depleted oil reservoir conversions.