储层条件下煤吸附甲烷能力预测

煤的吸附能力受煤的性质（煤阶、煤岩组分、煤体变形）和环境条件（温度、压力）的控制。探讨储层温度、压力下的煤吸附能力是含气量预测的前提和基础。根据Polanyi的吸附势理论，结合实测等温吸附数据，首先绘制了煤吸附甲烷的吸附势特性曲线，然后建立反映吸附量、温度和压力三者之间关系的数学模型。此模型可在已知某一温度下的吸附等温线时，计算任一温度、压力下煤的吸附能力，也就是储层条件下的理论最大含气量。该模型的建立使得定量评价地质历史时期煤层气的聚集与散失成为可能，并且在沁水盆地东南部得到了成功应用

PREDICTION ON COAL ADSORPTION CAPACITY UNDER RESERVOIR CONDITIONS

Coal adsorption capacity is controlled by coal property (such as coal rank, coal component, and coal deformation) and environmental conditions (such as temperature and pressure). It is the foundation of gas content prediction to study the coal adsorption capacity under the reservoir temperature and pressure. By Polanyi's adsorption potential theory and combining measured isotherm data, the characteristic curve of coal adsorption is drawn. Then the mathematic model describing the relationship among adsorption capacity, temperature and pressure is established. When one isotherm is measured, the coal adsorption capacity under any temperature and pressure can be calculated by using the model. Therefore, the theoretic maximum gas content of coalbed methane reservoir under any burial depth can be determined. This model provides an effective method for quantitatively estimating the evolution of gas content during geological history, and is validated with the data collected from the southeastern Qinshui Basin.