Development of gas production type curves for coalbed methane reservoirs

Coalbed methane is an unconventional gas resource that consists on methane production from the coal seams. The unique coal characteristic results in a dual-porosity system. CBM reservoir performance is also influenced by the interrelationship of reservoir, geologic, and operation parameters. Coalbed methane production data is considered a complex and difficult to analyze especially at the early stages of the recovery.; This study was conducted to develop a simple and reliable tool to predict the performance of CBM in The Northern Appalachian Basin. To achieve this objective, four steps were performed. A unique set of gas production type curves for coalbed methane was developed as a simple and economical tool for small producer to evaluate economic feasibility, increase recovery, and maximize efficiency. A correlation for peak gas rate estimation was also proposed as an alternative to forecast gas production without having production data. This approach was performed as a contribution to the development and growth of gas reservoirs in the Northern Appalachian Basin.