Simulations on recoverability performances for a coalbed methane field in SE edge of Ordos basin, China

摘要

This paper mainly studies the recoverability performances for a coalbed methane (CBM) field located in the southeastern edge of the Ordos basin of China. Geological models are established, and drainage performances for four typical wells are described in detail. Single well simulations for the four wells are conducted to check accuracies of parameters and predict well drainage performances, and optimizations of well spaces are simulated to determine the most suitable well space. Results indicate that the reservoir parameters used in this study are quite accurate, and the well space of 350 x 300 m is most suitable in this area. Furthermore, the fifteen years' field simulation under the well space of 350 x 300 m is conducted, which shows that the well number, average production and cumulative production are 1944, 7.01 x 10(8) m(3)/d and 105.22 x 10(8) m(3), respectively. To validate the well space used in this study, analyses of recoverability and economic profit are conducted, both of which demonstrate that the well space of 350 x 300 m is most suitable in this area and can bring a stable drainage performance for a long time and get a high gas production.