Ensuring optimal plant performance with ORYX GTL

Topsoe’s cooperation with ORYX GTL in Qatar is a story of ambitious goals, technical advances and shared determination.

The highway from the Qatari capital of Doha shoots northwards across the desert for 80 kilometers before arriving at Ras Laffan Industrial City, a vast industrial hub where Topsoe has helped realize a national ambition.  Here we find ORYX GTL, a joint venture between the state-owned Qatar Petroleum (51%) and the South African-based energy and chemicals company Sasol Ltd (49%). Topsoe’s proprietary equipment, catalysts, service, engineering design and licensed technology are all involved in the ORYX Gas-to-Liquid (GTL) facility inaugurated at Ras Laffan in 2006 by the Emir of Qatar. At the time, the plant carried a price tag of around a billion dollars and was the largest of its kind – a first step towards Qatar’s stated ambition of becoming the ‘GTL capital of the world’. “And today Qatar is the world’s GTL center,” says Business Development Manager Albert Van Wyk, who works for ORYX GTL in Qatar.  “Ninety per cent of the world’s GTL fuel is made in this country.”

Optimal performance – on the road and in the plant

GTL Diesel is the primary product of the ORYX GTL plant, which also produces GTL Naphtha and liquefied petroleum gas (LPG). The feedstock for these products comes from Qatar’s enormous offshore reserve of natural gas, which is brought up from below the Gulf north of Qatar and transferred into the industrial city at Ras Laffan. As a transportation fuel, GTL Diesel is known as a premium product with a high cetane number, a low content of sulfur and aromatics and good cold flow characteristics. Its high quality makes it well suited to modern diesel engines; vehicles that run on GTL Diesel have substantially fewer emissions and much less engine wear. And while ORYX GTL produces fuels that perform optimally on the road, Topsoe is working with ORYX GTL to ensure optimal performance at the production plant.

Shutdowns can cost millions of dollars every day

Topsoe’s main contribution to the ORYX GTL facility is the plant’s syngas technology, including the autothermal reformer (ATR) in which natural gas is catalytically converted to synthesis gas. 

After this reforming, the synthesis gas is converted to wax using a process called low-temperature Fischer-Tropsch (a technology licensed by Sasol). Finally, the long carbon chains of the wax are hydrocracked (a technology licensed by Chevron) to become high-quality GTL Diesel and other liquefied products.

Topsoe’s gas reforming process is very important to the ORYX GTL plant. If something goes wrong with the ATR (or any other major element in the syngas process), it can shut down the entire operation while repairs are made. And that means loss of revenue while production stands still. “Every day of production means literally millions of dollars,” says Albert. “ORYX GTL is highly profitable, even by Middle Eastern standards.”

Addressing “teething problems” and unplanned stops

As the first commercial-scale facility of its kind in the world, the ORYX GTL plant experienced what Albert calls “teething problems” to begin with. During the commissioning of the plant,

Topsoe worked closely with ORYX GTL to monitor and interpret data collected from the plant, and technical experts at Topsoe offices in Denmark were on call to provide quick response to technical queries. Topsoe designed the ATR to operate with a low steam to carbon ratio in order to create an optimal syngas quality. One of the initial challenges, however, involved an ATR component called a CTS burner that suffered material loss due to corrosion. This reduced the operating time of the syngas unit. Today, a redesigned burner has been optimized to perform successfully for 2-3 years, and the learnings from this experience have been implemented at another GTL project in Escravos,

Nigeria. Going forward, Topsoe and ORYX GTL continue to investigate new optimization possibilities, often with the help of plant simulations.

An example of how unplanned stops are being minimized is a Topsoe innovation that can automatically place the ATR in a so-called ‘safe mode’ if operational problems begin to develop. The ‘safe mode’ slows down operations to 90-95% of full capacity before the problem becomes critical, allowing technicians to make necessary adjustments without a full-scale plant shutdown.

Minimizing costs of a turnaround

Unplanned and relatively short production shutdowns of the type described above are one thing.

Another optimization challenge has to do with what is known as a ‘turn-around’: a planned shutdown of up to 50 days or more, during which time maintenance is performed, components are replaced and the plant is thoroughly checked. Turnarounds are hugely expensive, both in terms of logistics and lost production time. They are also a fact of life in this business – but Topsoe is currently supporting ORYX GTL with an optimization project to extend the normal time between turnarounds from two years to three.  It’s a long-term and highly ambitious goal that involves optimizing every critical plant component for maximum life. For Topsoe, this means that each critical component in the ATR portion of the plant is regularly tracked using a color-coded system to indicate whether it is living up to its projected life expectancy. As component performance is optimized, the graphic expression of this tendency moves from red to yellow to green. Albert is pleased with Topsoe’s increasingly ‘green’ contribution to the turnaround goal: “Haldor Topsoe is instrumental in achieving this goal by focusing on technical enhancement to lengthen the operational lifetime of each component. The ATR technology is on track to increase the shutdown intervals from 2016 onwards,” he says.

A new customer agreement makes good cooperation better

In May 2013, the cooperation between Topsoe and ORYX GTL was further strengthened with a five-year customer service agreement. In it, ORYX GTL is guaranteed fast, 24-7 access to Topsoe’s technical support team at an agreed-upon rate. Topsoe, meanwhile, is kept aware of planned maintenance projects at ORYX GTL, and can therefore also guarantee a ready supply of spare parts and catalysts. Regular optimization meetings are held in Qatar and Denmark in which management and technicians can keep each other aware of any problems that need to be addressed. The meetings are also designed to keep ORYX GTL aware of any new technological breakthroughs achieved at Topsoe that could improve performance at the Qatari plant. Access to any and all such improvements is guaranteed in the new contract.

“Continuous improvement is one of the values of ORYX GTL,” says Albert. “Optimizing the plant is always an on-going priority in the quest to improve overall plant efficiency.” And Topsoe of course remains firmly committed to making optimal performance possible.

About Ras Laffan Industrial City

Nearly 300 sq.km in size, the Ras Laffan Industrial City is located 80 kilometers north-east of Doha and is the hub of Qatar’s natural gas based industries. ORYX GTL was the first (but no longer the only) gas-to-liquid production facility here; the production of liquid natural gas (LNG) is another major activity at Ras Laffan. Ras Laffan also encompasses an array of support functions including power plants, emergency services, a world-class port and a huge seawater cooling system used by all the industrial plants here. A daily stream of buses and cars bring in a work force representing more than 50 different nationalities. Visitors and employees alike pass through strict security checkpoints before entering the city.

About Qatar

The State of Qatar is a 4,416 sq mi. peninsula that extends into the Persian Gulf from the eastern side of the Arabian Peninsula. It shares a border to the south with Saudi Arabia and has a population of about 2.27 million, of which approximately 15% are Qatari nationals. A former pearl fishing center, Qatar has in recent years experienced explosive growth and is now one of the richest countries in the world, thanks in large part to its enormous oil and gas fields. The capital city of Doha is, among many other things, home to the satellite TV station Al-Jazeera; in 2022, Qatar

will host the FIFA World Cup football tournament. Under the leadership of the country’s current Emir, Sheikh Tamim bin Hamad al-Thani, Qatar is realizing a broad national development strategy that includes a diversification of the oil and gas industry. ORYX GTL complements this diversification by adding gas-to-liquid (GTL) products to the country’s energy mix, which also includes liquid natural gas, crude oil, condensates, natural gas plant liquids and other hydrocarbon liquids.

Sources: BBC News Middle East, Qatar Profile 2014 World Population Review, Qatar population