Did you know that much of the oil in the ground is still present after primary recovery? In the king’s english that means there is still a lot of oil left in a well even after 10 years of pumping. The reason oil production slows is that the natural drive that once pushed oil aggressively towards the wellbore has subsided. Normally, the natural drive is either water or gas in the formation. In this article, we look to explain some of the common enhanced or secondary/tertiary methods of oil recovery.
With oil hitting new highs every day, it is clear the cost benefit of utilizing technology to get at extra production makes sense. When oil was in the $10-20 range, the incremental cost of some enhanced oil recovery methods did not make economic sense.
One of the most common secondary recovery methods is a waterflood. Essentially, a waterflood is a reintroduction of water into the formation to create a drive to push more oil towards the wellbore. To increase the efficiency of a waterflood, new methods utilize Alkaline-Surfactant-Polymer floods and some explorers are introducing microbes into the wellbore to increase the sweep efficiency of the flood, both methods have been met with success.
One method I find very interesting and have used with success on one oil well is the radial jet enhancement. The technology utilizes jets of high water pressure to cut laterally into the formation up to almost 300 feet. The technology can be viewed at www.wellenhancementservices.com, ask for Steve Bowen if you are interested in utilizing the technology on some of your new or old wells.
With 80% of the oil still in the ground after primary recovery, there is still plenty of meat on the bone for utilizing EOR. New technologies are constantly being tested and will lead to greater gains in the future. One area I am very interested in is new drilling technology. The rotary drilling rig has not changed radically in 100 years but new advances are coming and we’ll discuss those in future blogs.