| Title | Utilization of Small Size Drilling Rig for Workover Operation in Dieng Geothermal Field |
|---|---|
| Authors | Daniel ADITYATAMA, Agung W. MUKTI, Dorman PURBA, Riviani Kusumawardani, Rany Putri, Farhan MUHAMMAD, R. Bayu Wibowo |
| Year | 2020 |
| Conference | World Geothermal Congress |
| Keywords | Dieng, geothermal, workover, well, scale, casing remedial, milling, Indonesia |
| Abstract | Dieng Unit 1 Power Plant is located in Dieng Geothermal Field, Central Java, and has been operating since 2002. Dieng Unit 1 is currently experiencing production decline due to problems in its wells. Apart from scaling problem in the production/injection wells, another most common problem in Dieng Geothermal Field is the casing damage due to casing collapse or corrosion. To address this issue, a workover campaign has been planned to remove the silica scale and remediate the casing damage by squeeze cementing and re-line or casing tie-back. The existing production facilities in the well pad poses a big challenge in performing workover in Dieng Geothermal Field, as the smaller unit like Hydraulic Workover Unit (HWU) will not be able to perform any casing tie-back. On the contrary, the bigger drilling rig options may not have small enough footprint that can be accommodated by the current well pad layout in Dieng. A proper workover method with the fit-for-purpose rig is significant to ensure a successful workover operation. This paper investigates the challenges in planning workover to remove mineral scale and remediate casing damage in Dieng Geothermal Field. The process of selecting the most suitable drilling rig type is also discussed, including the advantages and disadvantages of the available options. Finally, the lessons learned and room for improvement for the future planning and operation in Dieng is presented. |