海上深水气井间歇采气控水开发实验研究

Experimental Study on Intermittent Gas Production and Water Control Development of Offshore Deep Water Gas Wells

针对海上深水气井的间歇采气开发进行实验分析,对间歇采气的作用机理、关井时机及关井时长进行深入研究和优化。明确了间歇采气技术的主要作用机理:及时为气层增能,避免因气相流动能力强、气层能量损失快而导致底水层与气层真实生产压差变大所引发的水脊加剧。通过注水实验,获得了引起水侵速度加剧的注水压差,进而利用底水脊进压差原则确定关井时机。通过间歇采气技术开发底水气藏控锥机理分析,明确了关井期间储层内的压力场与流场的变化规律。通过优化筛选实验,确定了最佳关井时长。

Based on the experimental analysis of intermittent gas recovery in offshore deep water gas wells,the mechanism of intermittent gas recovery,shut-in time selection and shut-in time are studied and optimized.The main action mechanism of intermittent gas recovery technology is to increase energy for gas reservoir in time,which can prevent water ridge from aggravating due to large real production pressure difference between bottom water layer and gas layer due to strong gas flow ability and fast energy loss of gas reservoir.Through the water injection experiment,we can get the corresponding water injection pressure difference with the increasing water invasion speed,and then use the principle of bottom water ridge pressure difference to determine the shut-in time.The experiment of cone control mechanism for bottom water gas reservoir development by intermittent gas production technology is carried out and the variation law of pressure field and flow field in reservoir during shut-in period is clarified.Through simulation experiment,the optimal shut-in time is determined.