Wednesday 13 April 2011

Pearl GTL: the world's largest gas-to-liquids plant set for production

The world's largest plant to turn natural gas into cleaner-burning fuels and lubricants took a major step closer to production today when gas began flowing from a giant offshore field.

Pearl GTL will process around 3 billion barrels of oil equivalent over its lifetime from the world's largest single gas field, the North Field in the Arabian Gulf. The field stretches from Qatar’s coast and contains more than 900 trillion cubic feet of gas, equivalent to 150 billion barrels of oil, or over 10% of worldwide gas resources.*

The gas-to-liquids (GTL) plant — a joint development by Qatar Petroleum and Shell – will add almost 8% to Shell’s production worldwide — making it the company’s main engine for growth for 2012. It has a capacity of 260,000 barrels oil equivalent a day and is expected to ship its first product in 2011 and reach full production in 2012.

"We’re on the verge of starting up a project that will be a foundation for Shell’s future growth for decades to come," says Shell’s Country Chairman in Qatar, Andy Brown. "For Qatar it means another way to generate revenues from gas reserves, in addition to selling pipeline gas or liquefied natural gas. It diversifies the country’s revenue streams and provides long-term income."

The plant will produce cleaner-burning diesel and aviation fuel, oils for advanced lubricants, naphtha used to make plastics and paraffin for detergents. It will make enough diesel to fill over 160,000 cars a day and enough synthetic oil each year to make lubricants for more than 225 million cars. The products will reach customers in every major energy market through Shell’s global retail network.

In bringing Pearl to production, Shell engineers have built on more than 30 years of experience in gas-to-liquids technology. We built the world’s first commercial-scale GTL plant in Bintulu, Malaysia, in 1993. Pearl’s output of GTL products will be 10 times greater than Bintulu’s.

Safety Record

Building Shell’s biggest engineering project to date in Ras Laffan, a vast industrial zone on Qatar’s coast some 90 kilometres north of Doha, was a major feat. At the peak of construction, it involved more than 52,000 workers from over 50 nations.

Despite the massive number of workers involved and the complexity of Pearl’s construction, a strong safety culture helped Qatar and Shell achieve a record-breaking 77 million hours worked onshore without injuries leading to time off work.

Preparing for a Smooth Start-up

Getting the huge plant into full operation will take a series of carefully executed system start-ups. Pearl GTL’s control room — the nerve centre of one of the largest and most sophisticated plants ever built in the energy industry — has powered up.

The first turbines and auxiliary steam systems have begun to generate steam and electricity to power the plant. The first two oxygen separation units are up and running.

Drilling Record

Sixty kilometres offshore, natural gas from the North Field — discovered by Shell in 1971 — is now flowing from to two platforms standing in water up to 40 metres deep to feed Pearl GTL. Eleven wells were drilled for each platform in record drilling times for the field.

Two underwater 76–centimetre (30-inch) diameter pipelines are carrying the natural gas to a gas separation plant onshore that extracts natural gas liquids: ethane for industrial processes, liquefied petroleum gas (LPG) for domestic heating and cooking and condensates as a feedstock for refineries. The separation process also removes contaminants like metals and sulphur. The sulphur is turned into pellets and shipped to the nearest market to make hydrosulphuric acid, fertiliser or other valuable products.

Turning Gas into Liquid Fuel

The pure gas, or methane, that remains will then flow to the GTL section of the plant, where it will be converted in a three-stage process into a range of gas-to-liquids products using Shell proprietary technology.

Finally, the liquid hydrocarbon wax is upgraded using specially developed technology involving new catalysts into the range of products. It takes some 2,000 steps to prepare all GTL systems for production.

In Qatar, summer temperatures exceed 40°C (104°F) and rainfall is slight. Conserving water is critical. Pearl was designed to be self-sufficient in its use of water.

Pearl, the largest investment by Shell in any single project, is a fully integrated project spanning production from an offshore gas field to finished marketable products. Shell is funding 100% of the development costs under a profit- sharing agreement with the state of Qatar.