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GTL test plant expected to start-up within two months, says MacDowell
Kay Cashman PNA Publisher
BP Exploration (Alaska) Inc. says it is “expects to be in position to re-start” its gas-to-liquids demonstration plant in Nikiski “sometime in the next two months.
“We had two short duration start-ups in the last couple of months,” BP spokesman Dave MacDowell told Petroleum News Alaska Jan. 14. “We identified a fairly simple but important mechanical issue that needs to be solved before the test plant can re-start. … We’re in the process of solving that now.”
Once operating, the $86 million GTL plant is expected to convert 3 million cubic feet of natural gas to 300 barrels of liquid products per day.
MacDowell pointed out that the purpose of the GTL plant, which was initially scheduled to commence syncrude production in the spring of 2002, is to test the performance of “two proprietary pieces of technology -- our proprietary compact reformer technology and proprietary converter catalyst. … We’re taking our time to learn, taking the time to do it right.”
He said BP has a 12-18 month testing period for the two technologies once the plant is in production, but there is a possibility the company will prove-up the technologies in less time.
Successful performance of the plant, MacDowell said, “could have application anywhere in the world where there are stranded gas reserves.”
GTL solution to North Slope’s stranded gas? Is there a possibility the technology could be used to transport North Slope gas down the trans-Alaska oil pipeline?
Yes, said MacDowell, but the company’s “focus right now for the North Slope is a pipeline through Canada to the Lower 48. That represents the most viable option.”
During an energy workshop held in early April in Fairbanks, Steve Fortune, BP Exploration’s GTL program manager, said that some of the unique design characteristics of the GTL plant in Nikiski, such as water recycling, use of hydrogen as a fuel source and a small, modular-type of construction, are attributes which would greatly enhance the economics of building and operating a similar facility on the North Slope.
“What we’re building in Nikiski is off-the-shelf design reactor and an off-the-shelf catalyst, so there’s no real development there,” Fortune said. “What we’re looking at is the operating envelope.”
During his presentation, Fortune displayed a slide showing a scaled drawing of a conventional world class GTL plant, one already built and operating in Trinidad, he said. Contained inside the conventional plant drawing was the much smaller GTL plant that BP is building in Nikiski.
“Using our compact reformer technology, it’s one quarter of the size of conventional technology,” Fortune said. “That’s the real breakthrough.”
Reducing the size of the reformer, where the first stage of the gas-to-liquids conversion takes place, enhances the overall economics of the process, he said. And those cost savings are particularly applicable to construction and operation of such a plant on the North Slope, the design of which, he said in February 2002, could be complete within two years.
“Making everything smaller can compound and produce quite a significant savings for a project on the North Slope,” Fortune said at the energy workshop in April.
During the second stage of the gas-to-liquids conversion process, water is produced as a by-product. BP’s plant in Nikiski will recycle 97 percent of that water, he said, a great operational benefit if such an operation were located on the arid North Slope.
“That helps reduce the actual amount of freshwater needed,” Fortune said. “That helps for somewhere like the slope, which is an Arctic desert, where water is not in abundance.”
GTL mixed with viscous oil could be shipped via TAPS, says Alyeska During his presentation at the energy workshop at the University of Alaska Fairbanks in April, Mike Malvick, a system engineering head at Alyeska Pipeline Service Co., talked about options for using the trans-Alaska pipeline to transport GTL products from a yet-to-be built conversion plant on the North Slope to Valdez, the shipping terminal for existing crude oil exports from Alaska.
“We’ve got an asset that cost billions to construct in the 1970s. It’s in place and able to move any quantity of oil up to the capacity it was designed for,” he said.
Mixing GTL products with the existing crude flowing through the 800-mile pipeline his company operates could be particularly beneficial if more viscous oil is pushed through the pipeline in the future. The lighter GTL, Malvick said, could make the heavy crude easier and less expensive to transport.
The main drawback for mixing GTL with crude oil, he said, is that gas-based product loses its environmental value as a low sulfur fuel.
Another option for transporting GTL that UAF researchers and Alyeska personnel have considered is called batching. Under that scenario, batches of GTL would be shipped through TAPS. Each batch would be followed by a pig or other type of barrier within the pipe, then by a shipment of crude oil.
“You would have higher initial capital costs, because you would need to add tankage … and changes within the pump stations to assure separation of the two streams,” Malvick said.
While in theory, shipping GTL in batches would maintain the integrity of the higher value liquid, there could be some contamination from pipeline wall residuals, he said.
Growing need for GTL products A study by the federal Department of Energy in the mid-1990s indicated that crude prices of about $30 a barrel would be needed to make a North Slope GTL plant commercially feasible with the technology available at that time.
In addition to commercializing stranded gas, Fortune says BP sees a growing demand for GTL transportation fuels because they are “environmentally friendly.
“They’re very clean fuels, with no sulfur, very low nitrogen compounds and no aromatics. From an environmental aspect, the (GTL) fuels are very superior, high quality fuels produced,” he said.
In addition, development of the clean fuel source could open the door to other emerging technologies, Fortune said. “Not just transportation fuels, but other chemical feedstocks and power fuels in the GTL process.”
For example, the hydrogen produced in the chemical process could be used for other fuel sources. Right now, costs are prohibitive to produce hydrogen as a standalone product, but the GTL process “could be a bridge to the hydrogen economy.”
Editor’s note: Excerpts from articles written by Petroleum News Alaska contributing writers Patricia Jones and Allen Baker and published in the first half of 2002 were used in the above article. See PNA’s archives for more information on BP’s GTL test plant in Nikiski: www.PetroleumNewsAlaska.com
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