论文部分内容阅读
油气藏中广泛存在烃—水及其他气体和矿物盐类的混溶体系,其相变特征十分复杂,但对油气勘探开发的作用至关重要。通过调研中外有关烃—水混溶体系的资料,着重分析了气态地层水的存在条件及含水烃类体系的相变特征,结果表明,局部突发性的温度上升、压力减小及混溶体系含烃量增加,均有利于烃—水混溶体系的气化。现今测得的束缚水膜厚度受控于束缚水饱和度的影响,为动态变化量,不适宜作为储层下限进行评估;真正稳定的束缚水膜厚度应约为1.6nm,在一定的温度和压力及溶解烃浓度下,现今测得的储层物性下限一定可以降低。地层水的气化引起的盐析作用会降低油气藏的渗透率,增大油水界面压力,在开采过程中要注意气态地层水的变化。
Hydrocarbons widely exist in hydrocarbon-water and other gas and mineral salts immiscible system, the phase transition characteristics are very complex, but the role of oil and gas exploration and development is crucial. By investigating the data of hydrocarbon-water immiscible systems both in China and abroad, the existence conditions of gaseous formation water and the phase transition characteristics of hydrocarbon-bearing hydrocarbon system are emphatically analyzed. The results show that local sudden temperature rise, pressure decrease and miscibility system Increasing the amount of hydrocarbons, are conducive to the gasification of hydrocarbon-water miscible system. The thickness of the irreducible water film measured at present is controlled by irreducible water saturation, which is not suitable for assessing the lower limit of reservoir as the dynamic variation. The true irreducible irreducible water film thickness should be about 1.6 nm. At a certain temperature Under the conditions of pressure and dissolved hydrocarbon concentration, the lower bound of reservoir properties measured today can be reduced. Salting-out caused by gasification of formation water will reduce the permeability of oil and gas reservoirs and increase the pressure of oil-water interface. Pay attention to the change of gas formation water in the mining process.