OGME speaks to Saudi Aramco engineers to delve into the challenges in developing the country’s first non-associated gas field – Karan
A new beginning dawned in the annals of Saudi Aramco’s gas history last year. The first gas from Karan — the company’s first offshore non-associated gas field project — started flowing full time and was transported by a subsea pipeline to the onshore Khursaniyah Gas Plant.
Discovered in April 2006, Karan is the first non-associated gas field in Saudi territorial waters in the Arabian Gulf, 160 kilometers north of the company’s headquarters in Dhahran.
Offshore facilities at Karan consist of five production platform complexes connected to a main tie-in platform, installed with associated electrical power, communication and state-of-the-art remote monitoring and control facilities for safe and reliable operations from onshore.
Detailed design work began in 2008. The field was discovered when the Karan-6 well drilled into Khuff formations, finding gas in carbonate reservoirs laid down from 200 to 300 million years ago in the Permian and Triassic periods. With Khuff’s gross thickness of up to 1,000 feet, Karan’s is the thickest Khuff reservoir section ever encountered in Saudi Arabia. The Khuff formation is considered high pressure and temperature at a depth below 10,000’, and Karan lies in medium-depth waters of 40-60 meters.
OGME spoke to the Gas Reservoir Management Department (GRMD) Manager Adnan Al-Kanaan and senior consultants, Dr. Zillur Rahim and Michael Haas about the non-associated gas development in general to find out about technology application and challenges associated with the Karan offshore field.
Al-Kanaan heads a group of 80 engineers and technologists in GRMD, who, with the support and assistance of other Engineering and Geoscience Departments, are responsible for the planning and development of the gas fields in Saudi Arabia.
“The gas development programme is a major contributor to the Kingdom’s economy to maintain and support all domestic Saudi Arabia infrastructure, from steel and cement factories and electricity generation to desalination and petrochemical plants,” said Al-Kanaan.
“With the continuous increase of domestic energy demand, exploration, drilling, and production activities are on the rise. Karan field has been a major discovery added to the portfolio of our gas projects,” he added.
“The field was fast tracked and was put on production within five years of discovery. . Once the formation breaks down, it was difficult to heal losses and drill ahead. Hence, all precautions were undertaken ahead of time to avoid drilling challenges,” said Dr. Rahim.
A 110-kilometer subsea pipeline is transporting Karan gas to onshore processing facilities at the Khursaniyah Gas Plant.
The onshore facilities also include a cogeneration plant, a sulfur recovery unit with storage tank, substations and a transmission pipeline linked to the Kingdom’s Master Gas System (MGS). Karan, is designed to produce 1.8 billion standard cubic feet per day (SCFD) of raw dry gas.
“On the challenges in this particular project, the wells were initially planned to be drilled as extended reach off multi-slot platforms. The well trajectories were changed to S-shape to minimize loss circulation, while drilling across the massive naturally fractured Khuff reservoir without impact on field gas offtake production or well stability,” said Haas.
“In addition, the wells were completed with pre-perforated un-cemented liners,” Haas added, “that saved time and cost without impacting wellbore integrity and production.”
Much of the equipment was fabricated in-Kingdom, from high-pressure vessels and injection skids to fusion epoxy pipe coating. The majority of construction work for the plant was also executed by local contractors, Aramco said.
This is Saudi Aramco’s first offshore non-associated gas development. The success of this project and lessons learned have led to other discoveries and developments that have taken Karan lessons and experiences and converted them into new best practices for future developments.
