Published: 06/07/2011
Published: 06/07/2011
Near wellbore damage is often blamed for many production problems, it can manifest itself in many ways and is caused by almost anything that disturbs the formation; even producing hydrocarbons can lead to near wellbore damage. Knowing where the damage is and how it was produced can help prevent new occurrences, but oftentimes prevention is not possible. Perforation damage is one kind of damage that cannot be prevented; because the objective of perforating is to damage the formation by creating a tunnel as large and as deep as possible.
A new technique of consisting of producing controlled implosions constitutes the most effective way of removing perforation and other types of near wellbore damage, and this technique lends itself to provide quantitative values of well damage removal. This paper discusses how this new technique was developed, from concept and modeling to its effectiveness in the field as demonstrated by a number of jobs on wells with different types of damage. The results are extremely encouraging; in some wells production has increased by as much as three to four times, this production increase is sustained and the rate at which well formation damage occurs is significantly lower.
This paper presents field experiments conducted on four wells in the Libyan Desert, including logging data based on state of the art measurements, and giving new insights into near wellbore damage. Strategies are recommended to combat the effects of common near wellbore damage mechanisms and to address their root causes. These findings opened a debate that challenges some aspects of industry accepted perforation techniques, and presents conclusive evidence that some well damage is in fact beneficial.