Oil production optimization without natural gas constraints: The harvesting of upstream natural gas

In a study performed on a theoretical reservoir and modeled after a West African deep-water field which has approximately 2 billion barrels of oil in place, twenty (20) producers, six (6) gas injectors and twelve (12) water injectors, it was determined that an additional 193.5 million barrels of oil could have been produced over ten years had there not been a limit to the gas production rate to be handled. The maximum field gas production rate per day in this study was 1060 MMSCF/d, of which 415 MMSCF/d was re-injected daily into the reservoir. The maximum field oil production rate was 250,000 STB/d and the maximum field water production rate was 80,000 STB/d. This work shows the advantages of eliminating production constraints imposed by natural gas production. With gas harvesting, the field oil rate can be optimized to ensure that the reservoir is producing at its true potential.