At least five producers, led by EOG Resources Inc., are experimenting with shooting highly-pressurized natural gas into past-their-prime wells that have seen their output slip. The wells are then capped to build up pressure inside with the aim of dislodging any oil still hiding in the rock.Note: there are three others posts regarding EOR using natural gas.
Other notes from the linked story:
The methodology’s been used in conventional wells elsewhere with both natural gas and carbon dioxide for years, but it’s just now emerging in America’s fracked shale fields.
The win-win goal: The trapped gas is put to work, and there’s a 30%-to-70% gain in oil output from older wells, according to EOG.
In late 2018, Permian flaring -- the burning off of associated gas -- more than doubled from a year earlier to 500 million cubic feet a day, and that’s likely to rise.
Generally, the use of injected gas is known as enhanced oil recovery, or EOR. Initially, EOG was the main company using natural gas to boost shale oil output, Krishnamoorti said by telephone. "But the fact is that now we have seen four other producers do it," he said. “And with remarkable results.”
EOG has been experimenting with EOR for at least three years in the Eagle Ford basin. Gas injection can potentially extend crude production volumes in older wells by 18 to 24 months, Krishnamoorti said. What’s still to be determined is how well EOR works in different types of rock formations.
For the most part, producers have disclosed little specific information about how well the new method performs, even in the Eagle Ford, where it is increasingly being adopted.Much, much more at the link.