CU Burns 'Torrefied' Wood Instead of Pure Coal in Test

KSMU Ozarks Public Radio, Friday, 14 August 2009

City Utilities of Springfield invited local journalists out Thursday to witness an experiment in burning something other than coal to produce electricity. KSMU's Jennifer Moore took them up on the invitation and headed out.

CU Experiments By Burning 'Torrefied' Wood

The monitors in the control room at the James River Power Station indicate whether the test burn is working. (Photo credit: Jennifer Moore)

Reporter: "Right now, I'm at the James River Power Station, just southeast of the city limits, near Lake Springfield. I'm surrounded by rather large hills of black coal, and looming over my shoulder are four enormous smokestacks. This coal is obviously burned to provide energy for the city. But the reason why we're here today has to do with a much smaller pile of what looks like dark sawdust. This is torrefied wood. And City Utilities is doing a test today to see whether this torrefied wood could be blended with coal to provide an alternative source of energy."

"We're gonna burn some of the torrefied wood we made in a plant in Missouri for a test," said Andrew Livingston, president of Earthcare Products Incorporated, based in Independence, Kansas. His company designs and engineers biomass energy systems, including producing torrefied wood. He arranged for this pile of wood to be here today.

(from MPUA Missouri Public Utility Alliance )
Torrefied wood is created by “roasting” wood chips in a large furnace to remove moisture and make the product
more brittle. This process physically and chemically changes the chips making them easier to crush for burning in
specific generating units. The final product will be blended with coal for burning in James River Power Station –
Unit 3. James River Power Station went into service in 1957 and has five generating units. Unit 3 provides 44
megawatts of electricity and has been in service since 1960.

Should results of the test be successful and approved, it’s estimated that by blending torrefied wood with coal at a
10 percent mixture, over 100,000 tons of coal would be replaced annually at James River Power Station. Final
results of the test burn are expected later this fall.

More detail from a related article:

August 14, 2009
From the Springfield Missouri News Leader
CU's torrefied test burn 'largest ever in nation'

City Utilities are crews monitoring pollution levels, systems during trial run.

Torrefied Wood

Wes Johnson

City Utilities began testing a new kind of fuel made from "precooked wood" Thursday at the James River Power Station.

For 67 hours, the power plant is expected to burn 50 tons of "torrefied" wood to see if it's compatible with the burners and pollution control systems at the plant. The test will end Saturday.

If it works, CU officials could replace up to 100,000 tons of coal with the cleaner-burning biomass material and give new life to the James River facility, which came online in 1957.

The test burn -- 10 percent torrefied wood and 90 percent coal -- took place in one of the power plant's five boiler units.

"Our plan -- if it works -- is for all of our units to burn this material," said plant manager Steve Myers. "Our intention is to eventually replace 100,000 tons of coal with torrefied product."

The test burn was the largest ever conducted in the nation, Myers said.

CU crews will monitor pollution levels from the mixed blend and measure how much carbon dioxide it produces. Crews also will observe whether the blend clogs any of the power plant systems.

Piles of torrefied wood are being conveyed into the power station where they mixed with 10 percent of coal before burning to produce electricity during a test burn at James River Power Station on Thursday. (Steve J.P. Liang / News-Leader)

CU paid $29,000 for the 50 tons of torrefied wood from Earth Care Products, Inc., an Independence, Kansas-based biofuel company.

Earth Care President Andrew Livingston said the product will reduce lead, mercury and carbon dioxide emissions when blended with coal.

Torrefied wood is created by heating it to more than 500 degrees in a low-oxygen environment, without igniting it.

The process drives out water, prevents it from absorbing additional water and makes the resulting charcoal-like material very easy to turn to powder in CU coal grinders.

Livingston said torrefied wood generates about 12 percent more heat than coal and costs less if made from waste wood such as tree trimmings, saw mill waste and storm debris.

It costs more than coal if the wood is grown and harvested, he said.

However, wood isn't the only fuel source for the torrefaction process.

Livingston said any kind of vegetative matter -- switchgrass, hay bales, corn stalks and other farm field debris -- could be converted into cleaner-burning material than coal.

CU already has approached the City of Springfield about acquiring material from its yardwaste recycling centers.

Crews hired by CU to cut trees and branches away from power lines also could be a source of wood material.

With new federal rules to reduce carbon emissions likely around the corner, CU officials are ready to move quickly toward acquiring a torrefaction plant.

Control operator Tom Hoff and his colleagues monitor the equipment in the control room during test burn of torrefied wood at James River Power Station on Thursday. (Steve J.P. Liang / News-Leader)

The utility is seeking requests for proposals, and Livingston said Earth Care is interested in submitting a proposal.

Myers estimated the plant would cost between $8 million and $10 million and could be up and running in less than a year -- if the test burn succeeds.

He said the plant could be built without an electric rate increase to pay for it.

Still, there are some hurdles left to jump.

The Missouri Department of Natural Resources gave CU permission to do the test burn.

But Scott Miller, CU manager of power supply, said CU would need permits from DNR and the Environmental Protection Agency to use torrefied wood on a regular basis.

Other fuel sources, such as grass or field waste, might need separate permits.

"We're going to have to work hand-in-hand with DNR on this," Miller said.

If the product works at James River, Miller said CU might be able to use it at the Southwest and new Southwest 2 power plants.

Because the pollution control equipment is different, Miller said CU would need to do additional test burns at the two plants before adding the material to the daily coal burn.