Co-optimization of natural gas recovery and carbon dioxide storage, North Triumph Reservoir, Nova Scotia

Climate change continues to be a subject that is discussed widely in the media, in politics, and within scientific communities. Some research indicates that human activities are responsible for an increase in the earth's surface air temperature over recent decades. Research also indicates that this warming trend will continue into the future resulting in such events as rising ocean levels, melting ice caps, warmer global temperatures and stressed eco-systems.; One potential way to dispose of CO2 for the long term is to inject it into depleted oil and gas reservoirs. This method can also enhance the recovery of oil and gas due miscibility effects, in the subsurface. Enhancing the recovery of oil and gas makes storage of CO2 in depleted oil and gas reservoirs interesting due to the potential economic upside.; The current study investigates the optimal scenario for sequestering the maximum volume of CO2 while also maximizing natural gas production from a reservoir. The reservoir is the North Triumph, located off-shore Nova Scotia, and is part of the Sable Offshore Energy Project. The reservoir is comprised of deltaic sandstone that is Cretaceous in age, located at a depth of 3,700 m subsea.; The simulation model was built largely from publicly available information, including well logs, the Development Plan Application, and also by contacting personnel responsible for operating the field. The simulations were run with Eclipse, a publicly available software package.; It was discovered, based on the simulation cases run, that CO2 injection does not markedly enhance the recovery of natural gas when compared to traditional water injection methods. For example, a water alternating CO 2 flood was found to increase the gas field incremental recovery by 16%, the same value as straight water injection. It is likely that some tax relief would be required to make CO2 injection an economical practice.