水驱气藏动态储量计算新方法

在对气藏动态储量计算方法研究的基础之上，结合水驱气藏的渗流特征，建立了确定水驱气藏动态储量的新方法。新方法针对水驱气藏，首先建立了气藏含水率与相对渗透率的关系式；其次，利用气水相对渗透率曲线确定了气、水相对渗透率比值与含水饱和度的关系式；在此基础之上，推导出水驱气藏采出程度与含水率的关系式；再者，利用水驱气藏采出程度与含水率的关系式建立起水驱气藏累积产水量与累积产气量的关系式，该关系式被定义为水驱气藏的水驱特征关系式。根据水驱特征关系式，结合水驱气藏的生产动态资料，即可作出水驱气藏的水驱特征曲线，利用水驱特征曲线所获得的参数可确定水驱气藏的动态储量；最后通过实例计算验证了新方法计算结果的准确性与实用性。

A New Method for Dynamic Reserves Evaluation of Water-drive Gas Reservoir

Based on the research of calculation method for dynamic reserves of gas reservoir,combined with the seepage characteristic of water-drive gas reservoir,this paper establish a new method for calculating dynamic reserves in water-drive gas reservoir.For water-drive gas reservoir,the relationship between the relative permeability and the water content of gas reservoir is established firstly.Secondly use gas-water relative permeability curve to determine the relationship between water saturation and gas-water relative permeability ratio.On the basis of it,the relationship between water content and degree of reserves recovery of water-drive gas reservoir is established,according to which the relationship between cumulative water production and cumulative gas production can be determined.The latter relationship is defined as water-drive characteristic relationship for a water-drive gas reservoir.According to the water-drive characteristic relationship,combined with production performance data,the water-drive characteristic curve can be established.The dynamic reserves of water-drive gas reservoir can be determined by using water-drive characteristic curve parameter.Finally,the case study verifies that the new method is accurate and practical.