ND coal-drying plant passes first large-scale test using New Zealand lignite; more trials set

ND coal-drying plant passes first large-scale test

BISMARCK, N.D. — Operators of a coal drying plant in southwestern North Dakota said the new factory has passed its first commercial-scale test using 450 tons of low-grade lignite from New Zealand.

Robert French, the chief executive officer of GTL Energy USA Ltd., said the plant near South Heart successfully removed 65 percent of the water from the low-quality lignite, allowing it to burn cleaner and produce more than 40 percent additional energy.

“The technology has been proven at the South Heart plant,” French said of the factory, which was completed in March after about 15 months of construction.

The New Zealand lignite was shipped in December to the North Dakota plant, where it was dried into chunks the size of barbecue briquettes using a process called benefication. About 20 tons of the dried lignite was tested successfully at a coal-fired power plant in southwestern North Dakota, French said.

The remaining briquettes were loaded on rail cars and transferred to an ocean freighter on the West Coast about two weeks ago, French said. Once in New Zealand, the briquettes will be tested by commercial users, he said.

GTL Energy USA Ltd. is a unit of GTL Energy Ltd. of Adelaide, South Australia. The American plant is part of a joint venture between GTL Energy and Solid Energy, a mining company owned by the New Zealand government.

French said a plant using GTL Energy’s benefication technology may be built in New Zealand.

The North Dakota plant is the first commercial-scale project of its kind and is designed to process about 240,000 tons of lignite annually, he said.

North Dakota state geologist Ed Murphy said there are 150 billion tons of proven lignite reserves worldwide. Only Australia, with 37 billion tons of proven lignite reserves, has more than North Dakota’s 25 billion tons.

While plentiful, lignite can contain up 30 to 60 percent water, making it inefficient to burn and heavier and more costly to transport. Drier coal creates more energy and lessens the amount of power needed to process and burn it, reducing pollution from factory stacks.

“Drying lignite improves its efficiency,” said Steve Van Dyke, a spokesman for Bismarck-based Partners for Affordable Energy, a coalition that supports coal-based electricity. “Reducing its moisture content is a good thing to do.”

The South Heart plant is slated to process a test shipment of Indonesian lignite later this year, French said. North Dakota lignite also can be processed at the plant, and sold to facilities that use coal-fired boilers, such as factories, hospitals, penitentiaries and universities, he said.