Simplified Prediction of Reservoir Pressure in Coalbed Methane Wells

Abstract Prudent coalbed methane (CBM) reservoir management and optimization requires knowledge of reservoir pressure. This paper presents a simple three-step method to predict reservoir pressure throughout the producing life of a coalbed methane well using only initial reservoir pressure, Langmuir pressure and cumulative gas produced. Use of the method has the potential to significantly reduce operating costs by minimizing the number of pressure surveys required to understand, operate and optimize a well or reservoir. The equations and process used to predict reservoir pressure are discussed, results of simulation studies validating the method are presented and actual examples from Fruitland Coal wells in the San Juan Basin are used to test the applicability of the method to real world conditions.