Abstract

Since 1975, most Handil wells have been equipped with a standard dual tubing multizone completion because of the reservoir type (multi-layer sand reservoirs). Water injection and reservoir depletion have made artificial lift necessary for an increasing number of strings. Gas lift has been chosen since 1980 on the assumption that dual gas lift would be feasible. Preliminary investigations showed that, while dual gas lift had already been operated on a few other fields but never on a large scale, it should nevertheless be feasible with careful design and close monitoring. Two techniques were selected for trial in Handil.

a) Dual gas lift with one string on conventional gas lift using Side Pocket Mandrels, and one string with gas lift through a macaroni string (gas rates for each string are independant).

b) Dual gas lift with both strings equipped with Side Pocket Mandrels and gas injected through the annulus for both strings (Dual annulus gas lift).

After 4 years of experience with dual gas lift in Handi we have considerably improved our confidence in dual gas lift techniques. The dual macaroni/SPM technique is currently producing 15,000 BLPD or 10% of the gas lift product, while the dual annulus gas lift is currently producing 30,000 BLPD or 20% of the gas lift product. We have now established specific design methods and monitoring rules for dual annulus gas lift.

This paper describes Total Indonesie's experience with dual gas lift in Handil field and details the specific design and exploitation techniques developed to successfully implement dual gas lift, with consideration of both technical and financial aspects.