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The Spokesman-Review Newspaper
Spokane, Washington  Est. May 19, 1883

Wood slash becomes biofuel for paper mill

Mikael Kamph of MK Energiflis of Sweden demonstrates the use of an $800,000 chipper Monday in Athol. The chipper is designed to turn the tops of trees and other timber waste materials into biomass. (Kathy Plonka)
Beckyk@Spokesman.Com, (208) 765-7122

The grinder sucked in lodgepole pine branches. It chewed them up and spit out wood chips. About two dozen logging contractors watched Monday as the Bruks mobile grinder, a Swedish- made machine, consumed a two-story-high slash pile on Bunco Road near Silverwood Theme Park.

The chips will be trucked to a Lewiston pulp mill and burned for power generation.

Modern Machinery Co., a heavy equipment dealer in Spokane, arranged the demonstration.

“We wanted to show people what biomass looks like,” said René Van Der Merwe, the company’s product manager for forestry.

For some, the idea of burning wood for fuel raises the specter of a wholesale raid on the forest.

“They think it’s an excuse for more logging,” she said.

But biofuel proponents say they’re wringing value from tree parts that would otherwise be burned as waste on slash piles. Branches and tree tops fed to the grinder Monday came from lodgepole stands, where hundreds of spindly trees crowded each acre. The private landowner wanted the stands thinned to reduce fire danger and encourage the growth of bigger, healthier trees, said Rod Burleson of Parkland Forest Management, the project’s logging contractor.

Some logs will be sold to sawmills or newsprint plants. But trees less than 2 1/2 inches in diameter are fed through the chipper.

“You’re not going to cut high-value saw logs to burn as biomass. It wouldn’t pay,” Burleson said. “This stuff here doesn’t have other merchantable value. … It would all be burnt in the woods.”

The chewed-up branches, tree tops and puny trunks are trucked 130 miles to Clearwater Paper Co.’s Lewiston pulp and paper mill, where the biomass is burned in boilers. The resulting steam powers the mill’s machinery and turns turbines for electricity, said Chad Farrell, the plant’s fuel buyer.

Biomass holds tremendous potential as an energy source, but it’s still a low-margin industry in the Inland Northwest, said Mick Buell of Buell Trucking in St. Maries, which also operates grinders.

Operators typically invest $1 million or more in equipment, said Modern Machinery’s Van Der Merwe. Diesel costs erode profits if the fuel is trucked too far from the woods.

Modern Machinery recently started promoting the Bruks mobile grinder, which retails for more than $800,000 and chips 200 to 350 tons of wood slash per day. A fuel-efficient engine reduces diesel costs, Van Der Merwe said. The machine is also maneuverable enough to drive up steep hillsides.

That gives it an edge on other chippers, said Burleson, the logging contractor. Some sites are too difficult to reach with a standard grinder pulled by a truck, he said.

Van Der Merwe made two trips to Sweden last year to research grinders. About 42 percent of that nation’s energy comes from renewable sources, with woody biomass the primary contributor, she said.

“With bioenergy, we have a new opportunity to tell people about the value of trees,” Van Der Merwe said.