Publications

Semberah Field, the northern most area of Sanga-Sanga, has been producing for more than 25 years where most of wells are flowing below minimum critical velocity. Surface facilities optimization and low-pressure technology had already applied thus reaching the lowest production line pressure around 100 psig with suction compression system around 20 psig. Meanwhile, most of remaining reserves locked in depleted reservoirs. Therefore, further depletion approach to maximize recovery is required in this mature field. As a part of production strategy, separating production pressure system into High Pressure (HP), Medium Pressure (MP), and Low Pressure (LP) by installing manifold (so-called ligature) at each gathering point is yet successfully increases well flowing flexibility and allows nearest well which has similar FTHP flow into same pressure system. Pressure mapping, critical rates calculation, and abandonment pressure simulation at various pressure systems have been performed to optimize well productivity. This paper discussed the effort of lowering FTHP liquid-loaded wells into VLP system by utilizing idle wellhead compressors (WHC). Integrated WHC screening was applied to obtain better well candidates to achieve both well sustainability and WHC utilization. In three consecutive years, total 25 idle WHCs relocation has successfully lowering FTHP 21 LP wells from 140 to 35 psig with average gain 0.5 MMSCFD and reviving 4 cyclic wells into continuously flow with average gain 0.2 MMSCFD. This production optimization was proven arresting base production decline rate from 67% to 30% in observed field. Semberah ligature system has evolved in response to nature of deltaic environment and well deliverability. WHC application overcomes the production facilities limitation to achieve the lowest FTHP well.