Pertamina and JOGMEC (Japan Organization for Metals and Energy Security) jointly conducted the first CO2-EOR pilot project in the Jatibarang field in West Java, Indonesia using the “huff and puff” method in October 2022.
The objectives behind the huff and puff CO2 injection are to utilize CO2 to boost petroleum recovery in the Jatibarang field, support Pertamina’s CCUS ambition, and validate the performance and response of the wells and reservoirs following a CO2 injection which will serve as an input in the development of field-scale enhanced oil recovery projects.
ABOUT THE JATIBARANG OIL FIELD
The Jatibarang oil field located in West Java was discovered in 1968 and is operated by Pertamina. The field produced around 7345 BOPD dan 50 MMSCFD of gas in 2021.
Its production peaked in 1982 and the field is expected to reach its economic limit in 2026. With a large percentage of oil remaining in the reservoir, it is considered a great candidate for enhanced oil recovery.
The Jatibarang field was chosen as the first oil field to undergo the CO2-EOR test.
THE HUFF AND PUFF PILOT CO2 EOR
In this pilot EOR using the huff and puff method, CO2 was injected into two wells: JTB-137 and JTB-161. Well JTB-137 and well JTB-161 were injected with 218 tonnes and 250 tonnes of CO2 respectively.
The huff and puff process in this pilot project consists of three stages:
- Injection of CO2 – 2.5 days
- Soaking – About two weeks
- Production – Up to three months.
The CO2 source is from Pertamina’s Subang field which is about 100 kilometres from Jatibarang. It was transported to the Jatibarang field by trucks.
RESULTS OF THE PILOT CO2-EOR
The two test wells were reopened at the end of the soaking period.
From well JTB-137, oil production increased from 10 BOPD to 47 BOPD, a big increase of 370% while the water cut declined by 30%.
From well JTB-161, oil production went up from 22 BOPD to 72 BOPD, an increase of 227% while the water cut decreased by 23%.
The pilot EOR did not show CO2 leakage. Over 70% of the CO2 injected is assumed to remain in the reservoir while approximately 30% resurfaced.
WHAT IS NEXT?
According to Deby Halinda, Expert Research and Tech Innovation at Pertamina, following the huff and huff test, further studies are needed to assess whether there is an interference between the wells. An in-depth geochemistry study will be necessary to further investigate CO2 effects on reservoir rock and fluids such as scale occurrence, CO2 solubility in water, and asphaltene buildup.
