储层渗透率对水合物降压联合注热分解的影响

Effect of reservoir permeability on hydrate decomposition under depressurization combined with heat injection

储层渗透率是影响水合物降压与注热联合法分解的重要因素。建立了包含守恒方程、反应动力学方程和辅助方程的三维水合物联合法分解模型,重点研究了不同储层初始渗透率条件下联合法解离过程,考察了压力、水合物分解及气、水饱和度变化特性。结果表明:储层渗透率越大,压力传播速度越快,储层压力水平越低;流体流动阻碍越小,注入热量热损失越小,反应时间越短;液相相对渗透率越大,液相流动性越强。但储层渗透率对气体饱和度变化影响不大。

The reservoir permeability is an important factor affecting the hydrate decomposition under depressurization combined with heat injection.Through establishing a 3D model of hydrate combination decomposition method including conservation equations,reaction dynamics equations and auxiliary equations,the combination method of hydrate decomposition under different initial reservoir permeability conditions has been reached,investigating the changes of pressure,hydrate decomposition and gas and water saturation.The results show that the higher the reservoir permeability is,the faster the pressure propagation velocity is;the lower the reservoir pressure level is,the smaller the flow hindrance is;the smaller the loss of heat injection is,the shorter the reaction time is;the greater the relative permeability of liquid phase is,the stronger the liquid phase fluidity is.But the reservoir permeability has a little effect on the change of gas saturation.