关于煤层气含气量临界深度算法的探讨

Discussion on Gas Content Critical Depth Algorithm of Coalbed Methane

文章使用TPAE方程将一系列等温吸附数据科学地转化为单个三变量(温度、压力、吸附量)函数方程。根据三元函数的全微分是每个自变量的微分之和,一阶全微分等于零时的温度和压力为临界温度和临界压力的原理,运用地温梯度与地压梯度的耦合关系和公认的地表恒温层温度,通过列表计算法和一元二次方程求根计算法来求临界温度和对应的临界压力。列表计算法可以计算出在拐点时的吸附量,以及出现拐点附近的温度区间(≤3℃)和相应的压力区间(≤1MPa)。

The temperature-pressure-adsorption equation(TPAE)is used to scientifically translate a series of isothermal adsorption data into a single three-variable(temperature,pressure,adsorption capacity)function equation.According to the principle that the total differential of the ternary function is the sum of the differentials of each independent variable,and the first-order total differential is equal to zero when temperature and pressure are at critical temperature and critical pressure,the coupling relationship between the geothermal gradient and the geopressure gradient and the recognized surface thermostatic layer temperature can be used to calculate the critical temperature and the corresponding critical pressure.This is achieved through the table calculation method and the root calculation method of univariate quadratic equation.The table calculation method can calculate the adsorption capacity at the inflection point,as well as the temperature interval(≤3℃)and the corresponding pressure interval(≤1MPa)near the inflection point.