Being the largest of its kind in the Middle East, Saudi Aramco’s first carbon capture and enhanced oil recovery pilot project demonstrates commitment to environmental stewardship.
Carbon capture and sequestration is the process of capturing waste carbon dioxide (CO2) from large sources, such as power plants, storing it and depositing it underground where it will not enter the atmosphere.
In the pilot project, 40 million standard cubic feet per day of CO2 will be captured at Hawiyah gas recovery plant and then piped 85 kilometers to the ‘Uthmaniyah field. At ‘Uthmaniyah, it will be injected — and sequestered, or stored — into flooded oil reservoirs under high pressure to enhance oil recovery, making it a win-win solution.
The project aims to enhance oil recovery beyond the more common method of water flooding, and is the largest of its kind in the Middle East.
“This breakthrough initiative demonstrates that we, as an industry leader, are part of the solution to proactively address global environmental challenges,” said Amin H. Nasser, acting president and CEO. “Saudi Aramco is carrying out extensive research to enable us to lower our carbon footprint while continuing to supply the energy the world needs.”
Reducing CO2 Emissions
Led by the Saudi Aramco’s EXPEC-Advanced Research Center, the company’s Carbon Management Technology Road Map includes many focus areas with a main goal of developing the required technologies to reduce CO2 emissions.
Reducing gas flaring, introducing zero-discharge technologies at well sites, and implementing a comprehensive water conservation policy at all plants and communities are among the company’s environmental protection efforts.
Environmental stewardship has long been a hallmark of Saudi Aramco’s business, with the company’s environmental protection policy formally established in 1963 and its Master Gas System, which significantly reduced CO2 emissions, in the 1970s.
The pilot project is the latest in the company’s list of efforts, injecting 800,000 tons of CO2 every year into flooded oil reservoirs. A monitoring system is in place to measure how much of that CO2 remains sequestered underground.
The project includes an elaborate monitoring and surveillance program that will collect data to evaluate its performance and build public confidence in the Kingdom’s — and the GCC’s — first CO2 sequestration project.
Two observation wells will measure how much of the 800,000 tons of injected CO2 will remain sequestered in the reservoir. It is estimated that as much as 40% of it will be permanently sequestered.
Monitoring will take place with a range of methods, including seismic monitoring, electromagnetic surveys, borehole and surface gravity, and inter-well tracer tests.
Near the ‘Uthmaniyah field, where the CO2 will be injected, a new standalone high pressure production trap, a new compressor and associated facilities for handling high concentrated CO2 production streams have been built. This gas-oil separation plant, a so-called GOSP, is where the monitoring of produced fluids will take place, and where Saudi Aramco engineers will ensure that as much of the CO2 as possible remains sequestered underground.
The facility has been retrofitted to include new facilities to handle recovered fluids for further processing.
Over the next three to five years, the pilot project will be studied by field engineers and researchers, and lessons learned from this project will be used at facilities and fields around the Kingdom.
The Hot Tap and Stopple (HT&S) team is on 24-hour standby to ensure that no disruption occurs to the company’s flow of oil through its vast network of pipelines.
With the average daily crude oil production of 2014 at 9.5 million barrels per day (mbd), keeping pipes that transport the crude functional is essential. This makes maintenance a delicate matter, and a standard repair would previously require shutting down pipelines — and disrupting operations — for several days.
The HT&S team has changed things; making it possible to safely cut into pipes, created a temporary branch to bypass the flow around the area requiring maintenance, and then replacing the valve — all without interrupting the pipeline flow.
Hot Tap and Stopple
Hot tapping is one of the most tested techniques for conducting repairs to a pipe or vessel while still under pressure.
The Hot Tap team can bore holes as small as one-quarter of an inch and as large as 56 inches into pipes that they repair. They can also operate in temperatures as high as 700 degrees Fahrenheit and 2,220 pounds per square inch of pressure.
Stopples are plugs that temporarily plug functioning pipes to isolate a segment for repair or modification. Stopple operations can isolate pipes up to 60 inches in diameter, and can operate at temperatures as high as 250 degrees Fahrenheit and pressures as high as 1,800 pounds per square inch.
Demand and Growth
Currently, Saudi Aramco’s HT&S team is the Kingdom’s only provider of hot tap services, and demand is strong. Nearly 200 HT&S operations are conducted per year over the past five years, and this number is likely increase as the company expands into petrochemicals and the Kingdom’s manufacturing industry grows.
The HT&S team currently services both company operations and third party partners.
The University of Oxford has conferred the title of Visiting Professor in Engineering to Gautam Kalghatgi, internationally renowned for research in the fields of fuels, combustion and engines.
Professor Kalghatgi is engaged at Saudi Aramco’s Research and Development Center in Dhahran. He works on better understanding fuel requirements of engines and on developing new, optimized fuel/engine combustion systems.
His recent work at Saudi Aramco demonstrates the implications of engine technology developments on the manufacturing and marketing of future transport fuels.
In his new role, he will teach and do research in the university’s Department of Engineering Science.
As the global energy demand for commercial transport increases more rapidly than for passenger cars, the availability of light low octane fuels will increase. Highly efficient engines which can use such fuels have to be developed to ensure the sustainability of future transport, including fuels manufacturing.
One option is Octane on Demand where spark-ignition engines run on such fuels and use high-octane fuel only when needed. The other option is to use such fuels in diesel engines (Gasoline Compression Ignition, where they are particularly suited to achieve low particulates and NOx, a major problem with conventional diesel engines.
Dr. Kalghatgi has contributed significantly to the scope and execution of two flagship programs in both these areas. He helps guide the research programs in fuel technology at the Saudi Aramco centers in Dhahran, Paris and Detroit.
He has an association with Imperial College London as a Visiting Professor in the Department of Mechanical Engineering and has held similar appointments in the past with the Technical University of Eindhoven, The Royal Institute of Technology, Stockholm and The University of Sheffield.
The King Abdullah University of Science and Technology (KAUST) has appointed him to the International Scientific Advisory Board of their Clean Combustion Center. He is a Fellow of the Royal Academy of Engineering and the Institution of Mechanical Engineers (IMechE) in the United Kingdom and of the Society of Automotive Engineers (SAE) and is on the editorial boards of the International Journal of Engine Research, IMECHE Journal of Automobile Engineering, and SAE Journal of Fuels and Lubricants. His book, “Fuel/Engine Interactions,” was published by the SAE in 2014.
Environmental assessment discovers dhubs on intended project site.
Dhub, or spiny-tailed lizards, spend most of the day basking in the sun, so they typically inhabit rocky areas with good shelter for when they need to burrow underground. However, they have suffered rapid population declines in recent decades due to habitat loss and overhunting.
Today the International Union for Conservation of Nature (IUCN) has classified the species at regional and international levels as “Vulnerable.” This means they face a high risk of extinction in the wild.
Relocating the Dhubs
Bulk earth moving work and site preparation activities for the Fadhili Gas Plant were scheduled to begin mid-April of 2015. To protect the local dhub population, Aramco’s environmental protection department arranged to capture and relocate the reptiles before construction activities at Fadhili began.
Relocation activities began in March 2015, and the dhubs have successfully been moved to their new home in a protected area within Manifa and are doing well.
Further monitoring of the relocated dhubs will continue for many months, and they are expected to start breeding in the spring season and bring to life a new dhub colony at Manifa.
The Berri Gas Plant department (BGP) has successfully commissioned and started-up a new, more efficient ethane liquefaction exchanger at the Ethane and NGL Recovery plant.
The new liquefaction heat exchanger has permanently replaced BGP’s existing ethane liquefaction unit and is the latest in their efforts to increase plant energy efficiency.
The Older System
The existing ethane liquefaction system was complex, consisting of 30 pieces of equipment and two big compressors to reach the required conditions for the ethane liquefaction system. This system was hard to operate and costly to maintain due to the quantity of instruments and the age of rotating equipment.
The old system also negatively impacted the environment by flaring 4 million standard cubic feet per day (scfd) of ethane due to recycle compressor trips. The liquefaction rate was also limited to 20 million metric scfd.
BGP recognized an opportunity to improve its ethane liquefaction process and minimize energy consumption by integrating the ethane and NGL recovery plant (Plant F-20) with the liquefaction process.
The initiative uses the available cryogenic process stream from de-methanizer overhead (-160° F) to liquefy ethane product. A side slip stream of de-methanizer overhead exchanges heat with the ethane product from the de-ethanizer reflux drums using a brazed aluminum heat exchanger (BAHE).
The new system is capable of producing 25 million metric scfd of liquid ethane along with keeping ethane outlet temperature as low as -105°F by maintaining methane gas inlet flow.