| Title | Novel method of dissolution of scale in the inaccessible geothermal wellbore |
|---|---|
| Authors | A.H. Sasoni, I. Hamzah, D. Wilson, Z. Mubarok, A. Hernawan, R. Pasikki, N.C. Amin |
| Year | 2025 |
| Conference | New Zealand Geothermal Workshop |
| Keywords | acidizing, calcite, scaling, Silangkitang, well recovery and stimulation |
| Abstract | SIL1-2, an old well drilled in 1997 located in Indonesia, initially produced up to 420 t/hr at 22 barg. By 2023, its production rate had declined to approximately 80-90 t/hr. A scaling simulation indicated that calcite deposits likely formed near the wellbore. Limited by wellbore accessibility, the only feasible stimulation method was Solenis patented well recovery and stimulation novel method. Since the wellbore was inaccessible, the acid stimulation was initiated under less-than-ideal conditions, with no scale deposit removal or pressure-temperature logging performed beforehand. The goal was to dissolve scale buildup within the wellbore and nearby formation, sweep the solution into the formation, and prevent calcium ions from redepositing, thereby expecting permeability enhancement. Laboratory tests on core samples, the only physical reference, involved exposing them to acid and alkali chemicals. After several days of preparation, SIL1-2 was brought back online, and production recovered to about 290–300 t/hr, nearly its original capacity, as confirmed by the production separator. The well recovery and stimulation successfully increased production while also minimizing equipment requirements and reducing loss generation compared to other stimulation methods previously attempted. |