Field experiment of CO 2-ECBM in the Upper Silesian Basin of Poland

A field experiment of CO2 storage in underground coal seams with simultaneous (enhanced) production of coalbed methane production was set-up and performed in Poland. An existing CBM well was put back into production to establish a baseline production. A new injection well was drilled 150 m away from the production well. A breakthrough of the injected CO2 in the production well was considered essential for understanding the operational results. First injection of CO2 took place in August 2004 in three seams of Carboniferous age. Continuous injection, circa 12-15 t/d, was eventually reached in April 2005 after stimulation of the reservoir by a frac job. Compared to baseline production, the production of methane increased significantly due to the injection activities. Recovery of methane is, however, low which is probably related to low diffusion rates into and out of the coal. Nevertheless, a total of 692 tonnes of CO2 are stored in the reservoir, most likely due to adsorption of CO2 on the coal. The results provide good hope for successful future upscaling of the operations and can possibly help to overtake start-up barriers of future CO2 storage initiatives in Europe.