Oil production from the field begin with the first oil in January 2003. Unfortunately, the wells produced viscous emulsion which caused the production decline rapidly. Further analysis of the production data showed that the decline in production over a long period of time is very consistent with organic deposition at or near the perforation interval.
Over the years, several analyses and production enhancement efforts including chemical and mechanical treatments have been attempted with minimal success. The damaging mechanism was determined to be caused by rare High Molecular Weight Organic Deposit (HMWOD) that have caused a significant pressure drop in the tubing, which consequently restrict oil production and tested to only disperse at above 90°C. It was suspected that the deposit was a naturally-occurring component of the crude oil itself, separating from the bulk of the crude as a consequence of the fluids movement towards the wellbore and the consequent drop in fluid pressure.
An eco-friendly nano-fluid was developed and pilot treatment conducted in February 2014, which successfully rejuvenated the well back to production. Subsequent treatment was conducted in early 2018 on the same well and later replicated on another well as part of technology maturation process. This paper incorporates laboratory tests conducted to customize the nano-fluid, engineering approach on the treatment volume, simulation analysis on treatment schedules, treatment procedure as guidance for offshore personnel and actual field result of the treatments.
Remedial treatment for near wellbore HMWOD using novel nano-fluid has successfully revived the wells back to production. Further development and replication would open-up bigger opportunities to unlock potential of wells with similar organic deposit issue throughout PETRONAS' operation.