The Success of Acid Fracturing Job In Water Disposal Injection Well In “NJT-25” Well of “Subang” Field

Adrian Indarti (D-3 of Petroleum Engineering Study Program, Institut Teknologi Petroleum Balongan, Indramayu 45216, Indonesia.)
Desi Kusrini (S-1of Petroleum Engineering Study Program, Institut Teknologi Petroleum Balongan, Indramayu 45216, Indonesia.)
Agustina Prihantini (D-3 of Petroleum Engineering Study Program, Institut Teknologi Petroleum Balongan, Indramayu 45216, Indonesia.)
Neo Jowintono (D-3 of Petroleum Engineering Study Program, Institut Teknologi Petroleum Balongan, Indramayu 45216, Indonesia.)

International Journal of Health, Engineering and Technology
Vol. 5 No. 3 (2026): Vol. 5 No. 3 SEPTEMBER 2026

Acid fracturing is one of the well stimulation methods that aims to restore or even increase the decline in well productivity caused by several factors, such as unstable production rates by giving a new way (bypass) to hydrocarbons. The NJT-25 well in the Subang Field is a well that was stimulated using acid fracturing on Friday, October 25, 2024. The NJT-25 well has a low permeability of Limestone rock mineralogy of about 2.2 mD with a porosity value of 12%. The mixing fluid used is Water Base Fluid, which is the water-based and acid-based mixing fluid used is 15% Hcl. The process of implementing acid fracturing begins with a step rate test, and immediately plays frac. The reason for acid fracturing in the NJT-25 well is that water injection wells as water disposal are less effective when injected with water because of the small rate of water injection, which is with a value of 365.49 BWPD. After acid fracturing, the NJT-25 well experienced an increase in permeability value of around 572.51 mD with an average permeability of around 9.2 mD followed by an increase in the productivity index (PI) with the Prats method of around 3.1 times and the Cinco-Ley method of around 3.3 times. The rate of water injection in the NJT-25 well is 1511.59 BWPD.