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An inventive mind: Harold Vinegar's mission to unlock new energy resources

For 30 years, Harold Vinegar has researched new ways to unlock the vast potential of oil shale and tar sands. His work has helped make the development of these unconventional resources a real possibility at a time when concerns over energy supply and security are on the rise.

by JAMES SCHOFIELD
October 29, 2007

Winter can be tough in the Piceance Basin in north-western Colorado – a desolate area nestled in a wild and remote stretch of the Rocky Mountains. Pioneers first settled there in the late 1800s. Deep snow regularly blankets the rugged landscape as average temperatures fall well below freezing. The dirt track roads that snake through the mountains are often impassable. So when Harold Vinegar, a promising young scientist at Shell, and a small team of researchers worked on a shoestring budget to conduct field research there in 1981, he knew conditions on the project would be far from luxurious.

The goal was to explore new, more efficient ways to unlock the region’s vast deposits of oil – estimated by the US government at one trillion barrels – locked in underground rock known as oil shale. Starting in late summer, the first phase of the project lasted longer than expected and the team pushed on through the winter. Holed up in a primitive log cabin, the team often ate deer, elk and even bear – trapped by their mountain guide. Mud covered the floor between bunk beds. Days were spent outdoors, riding snowmobiles to the site or stamping feet to keep warm during experiments. The high elevation – 9,000 feet (2,740 metres) – meant Vinegar woke each day with a headache and had to take aspirin every morning.

Despite the bitter cold, Vinegar remained upbeat. “These were severe conditions,” says George Stegemeier, who was a member of the team from Shell’s Bellaire Research Center in Houston, Texas, and has worked with him on and off ever since. “Harold always sees the bright side of things and is optimistic under the most trying conditions.” To save money, the team used a hand-operated drill to collect samples, rather than a more costly truck-mounted rig. When it wouldn’t penetrate the tough oil shale, he cajoled his colleagues to put their weight behind the project – quite literally: by leaning all their weight on the drill frame the scientists created enough downward pressure for the drill to bite firm and collect important core samples. “He always had a love of getting things done and doing them himself,” recalls Eric de Rouffignac, another colleague on the trip. “That was probably the most expensive use of PhD talent possible!”

For Vinegar, it was a dream come true – a chance to work with leading scientists and conduct research that might help transform the energy fortunes of the USA in the wake of the oil crisis of the 1970s. Over the following years, Vinegar focused on developing a range of new ways to find and extract difficult, unconventional energy resources, including oil shale and oil sands, a blend of tar-like oil called bitumen, clay, sand, and water. His ongoing research work has helped make that a real possibility at a time when concerns over energy supply and security are on the rise once again.

From Brooklyn to Bellaire

Since those early days in Colorado, Vinegar has had an eventful career. He has well over 200 patents to his name and has written countless papers in scientific publications. He is a member of the prestigious US National Academy of Engineering – which counts the world’s most accomplished engineers among its peer-elected members – as well as the US National Research Council and a host of other bodies. And in 2005, Shell appointed him as one of the company’s seven chief scientists – a newly created role to champion innovation and technology inside and outside the company and mentor young scientists.

“It’s been a record of continuous successes doing things many people thought were undoable,” says George Hirasaki, Hartsook Professor of Chemical Engineering at Rice University in Houston, and a fellow member of the National Academy of Engineering. Hirasaki has known Vinegar for many years, and worked directly on research projects with him. “He made paradigm shifts one after another.”

Vinegar has lost none of the boyish passion for science that first captured his imagination as a teenager growing up in Brooklyn, New York. His uncle, Bernard Goldberg, was a Shell mathematician who worked on calculating the probability of finding oil and gas during exploration. During World War II he had worked on the atomic bomb programme at the Oak Ridge National Laboratory in Tennessee. “Bernie’s tales were really exciting,” says Vinegar. “To a kid, what he was doing sounded amazing.”

After earning a bachelor’s degree in physics from Columbia University, Vinegar gained a PhD from Harvard University specialising in nuclear magnetic resonance – the study of the magnetic properties of the nuclei of atoms. After graduation in 1976, he joined Bellaire Research Center.

At the time, the USA was still reeling from the energy crisis sparked by the OPEC oil embargo imposed on countries that supported Israel during its conflict with Syria and Egypt in the 1973 Yom Kippur war. With the memory of lines of American motorists desperately queuing for petrol still fresh in people’s minds, and a real fear taking hold of how vulnerable the economy was to supply problems, the hunt was on for technology that would get the most from existing domestic energy resources and unlock new ones.

Vinegar describes that time as a golden era for the Bellaire Research Center scientists. “We were given the freedom and money to conduct pure research – pure science. We were constantly learning. Energy just seemed such an important field to work in.”

From scans to pie in the sky

Over the next 30 years Vinegar worked on a range of projects. In one of the earliest he was keen to see whether new medical scanning technologies – that used a range of techniques to produce highly detailed images of the inside of patients’ bodies – could be used to analyse field cores, long cylindrical samples of rock and earth obtained by boring into the ground with a hollow drill.

Until then, scientists had analysed small individual samples of earth and rock – pulling them apart to test their electrical resistance, how porous they were and other properties. They then used the findings to try to predict the underground characteristics of oil and gas reservoirs. But these samples were often disturbed while being collected and often not typical of actual conditions in the field. Vinegar hoped that using scanners on long core samples would give more representative measurements.

He asked an old friend – Dr Arnold Goldman, a radiologist at the Playa Del Oro Hospital, in Texas – for help. When Goldman wasn’t using the hospital’s CT scanner for patients, he let Vinegar scan a core sample of sandstone prepared by saturating sections with oil and water. The results were promising: Vinegar was able to see clearly the distribution of oil and water in the sample on the CT scan. Further tests followed, but conditions weren’t ideal: experiments would sometimes be interrupted as doctors wheeled in patients. “We’d have to stop, take our rocks out of the machine and wait for the doctors to finish,” remembers Vinegar.

So he convinced Shell to buy its own CT scanner, a machine that uses a series of X-ray images taken in slices to build three-dimensional images of objects. He began researching how fluids and gas flow in rocks. Since Vinegar’s early successful experiments, others in the industry have followed suit, and the CT scanner has become a standard tool for evaluating oilfield cores and an essential tool for oilfield research.

One of Vinegar’s most significant achievements was developing a way of using nuclear magnetic resonance (NMR) tools to search for gas underground. At the time, scientists thought the tools – which are lowered down oil wells, fire magnetic pulses and measure signals from the nuclei of hydrogen present in fluids – could only detect oil and water.

Vinegar’s breakthrough occurred in 1994 as he puzzled over the origins of an unidentified signal in test results obtained in a well in the Gulf of Mexico. He had a hunch that the signal was not from water but from natural gas. It was Sunday evening when he returned from the field, but instead of heading home to his family, Vinegar spent the evening scouring dozens of scientific papers to find support for his theory in the library at Houston’s Rice University.

Suddenly there it was – a single study by scientists in the Netherlands on the NMR properties of methane, the main component of natural gas. “Sure enough, sitting there in the stacks at two in the morning, I saw that the numbers for methane were unique and exactly matched the signature I’d found.” It was a eureka moment. “It’s a wonderful thing to think you’re the only person in the world to know something like that.”

Struggling to contain his excitement, Vinegar spent most of the night writing a description of his discovery and multiple ways it could be used. The next morning he rushed the invention description to a patent attorney. Over the next two years, he and a couple of colleagues obtained several patents for inventions based on the breakthrough. While other tools measure characteristics of reservoirs such as density and electrical resistance, NMR logging remains the only way to directly determine how much oil, water and gas are held in a reservoir.

Vinegar has been involved in countless other projects large and small during his career. But among them, the work on unconventional oil stands out. He has doggedly continued his research efforts to unlock the vast potential of oil shale and oil sands and is now the lead scientist of Shell’s newly formed organisation set up to develop them, EPW Unconventional Oil. The world’s so-called unconventional resources – including oil shale, oil sands, bitumen and heavy oils – are thought to contain oil equal to the world’s known conventional resources. That is a tantalising prospect at a time when reserves of easy-to-access oil are in decline and concerns over energy security are running high. And recent high prices for energy mean oil shale and oil sands – found in many countries around the world – are once again looking more attractive as economically-viable resources.

In the case of oil shale, people have been trying to find ways of extracting it profitably for at least a century. One method involves mining and crushing the shale and heating it in airtight kilns. This process – still being used in places such as China, Estonia and Brazil – uses large amounts of water and produces mountains of spent shale. The resulting oil is a heavy tar that requires further intensive processing and refining. It’s a costly and dirty process and helps explain why oil shale has yet to live up to its astonishing potential.

Instead of removing and processing the oil shale, Vinegar and his colleagues are experimenting with an in situ method to accelerate the conversion of kerogen – a solid organic material in the rocks – into high-quality, liquid hydrocarbons. Heaters lowered into drillholes slowly heat the rock to more than 300°C (572°F), turning the kerogen to light liquids and gas that are easier to refine into high-quality fuels such as naphtha, jet fuel and diesel.

The project has come a long way since the first tests. “It was real pie in the sky stuff,” jokes Vinegar. “The first effort in the 1980s was literally off the back of a pick-up truck.” Back then the team dangled a metal bailer from a fishing rod to draw small amounts of shale oil from the test wells. Step by step, more than a quarter century of continuous research has shown that the basic principle of heating the rock to release the oil works. On a 30-by-40 feet (around 9-by-12 metres) testing area, Shell successfully recovered 1,800 barrels of oil during a demonstration project in 2004 and 2005.

Nevertheless, a number of technical challenges remain that need more research. The focus now is on improving the heater design to make them more energy efficient and robust enough to withstand years of operation at high temperature. Further work is going on to study the impact on the environment. The project is now testing a freeze wall in Colorado to prevent water entering the heated zone and oil leaving it. The freeze wall is formed with pipes containing refrigerated liquids that cool the rock surrounding the heated area until it becomes an impermeable frozen barrier. Shell is investigating various ways to provide more affordable energy required to power the heaters and reduce the impact of carbon dioxide emissions from the process.

Though still a research project, Vinegar’s work with oil shale might one day have the potential to transform the global energy scene. It has already taken years of commitment, pursuing a challenging technology that could have dramatic results if successful. “I’m convinced unconventional resources such as oil sands and oil shale will play a key role in our energy future,” he says. “This is long-term thinking.”

Leading by example

It is also a reflection of Vinegar’s optimistic approach to research, which treats every failed experiment as a valuable lesson rather than a setback. Getting the long, rod-like heaters to work properly has been one such process of trial and error. In early tests, the heaters were overheating when adjacent to rock layers rich in kerogen, which conducts heat poorly. The heat they generated failed to dissipate through the shale: they became too hot and buckled. Despite the disappointment, Vinegar urged the team back to the drawing board. Further research led them to invent self-regulating heaters, a new design that produces less heat in the hot spot if the temperature exceeds a certain limit.

That determination to overcome setbacks, and his ability to coax the best from colleagues makes Vinegar well suited for his new role as mentor and coach. His willingness to encourage researchers to pursue hunches and give credit when those gambles pay off has helped countless younger scientists. “He was constantly pushing me, challenging me,” says Ilya Berchenko, a researcher who began his career in 1998 under Vinegar. “He treated me as an equal and made me visible to senior guys. I owe my career to Harold.”

Despite that talent to inspire people, Vinegar would probably like nothing better than to be back in that cold mountain cabin working to unlock one of the world’s greatest energy resources. “It was just great fun! There was a beauty about the hills and valleys. What more could I have asked for?”