高温高压凝析气藏气相中水含量计算新方法

准确计算气相中水含量是分析高温高压凝析气藏复杂相态特征的基础。凝析气藏高温高压条件下，气相中水分子和烃类分子发生缔合反应形成烃水化合物（ACnHm·BH2O），这是气相相态产生特殊性质的主要原因。基于相态平衡及流体热力学平衡原理，考虑高温高压凝析气藏气相温度、压力及密度对缔合反应的影响，建立了计算气相中水含量的四参数缔合模型，并采用多元回归法获得了四个模型参数值（ai）。通过实例分析与对比，论证了此方法的可靠性、实用性。

A New Method for Calculating Water Vapor Content of Gas Phase in High Temperature and High Pressure Gas Condensate Reservoirs

Calculating water vapor contents of gas phase accurately is a base of complex phase behavior analysis in high temperature and high pressure(HTHP) gas condensate reservoirs.In high temperature and high pressure gas condensate reservoirs,water and hydrocarbon molecules in gas phase are associated to form hydrocarbon carbohydrates(ACnHm·BH2O).This is the major reason for special characteristics in gas phase.Based on principles of phase balance and fluid thermodynamics equilibrium,taking into account the influence of high temperature,high pressure and the density on the associative reaction,association model with four parameters for calculating water vapor contents was established.The values of four model parameters(ai) were determined using multi-variable regression method.The new method is demonstrated reliably and practically by analyzing and comparing some examples.