Woody biomass enters a new phase with new technology


Biomass is a big part of the timber industry’s future, but what most people talk about when it comes to turning woody biomass into energy is a process called cogeneration. This is pretty straightforward: wood waste or wood pellets are burned in a plant to create electricity.

Now another type of biomass process is getting some attention: pyrolysis. The woody biomass is still burned, but it’s burned in a low-oxygen kiln to produce not electricity but liquid (bio-oil), charcoal (biochar) and gas (syngas). The bio-oil and the biochar, as of now, have the most lucrative potential.

Just last week, the Washington Department of Natural Resources hosted a demonstration near Cle Elum highlighting the power of pyrolysis. A Salt Lake City company, Amaron Energy, brought up its mobile “fast pyrolysis” reactor, built in a 45-foot-long freight container.

The bio-oil produced in pyrolysis is attracting special attention. The oil has the potential to be converted into car fuel, plastic, asphalt or heat for homes, and pyrolysis plants are being built or planned in several cities in Europe. Earlier this month ExxonMobil announced it’s investing $1 million to create an advanced biofuels research program at Iowa State University, a program that will initially focus entirely on fast pyrolysis.

What’s unique about the fast pyrolysis machine on display in Cle Elum is it’s mobile, which means it could be transported deep into timber areas. With wood waste so close and plentiful, the fast pyrolysis process suddenly gets a lot more economical.

A major challenge facing all the (biomass) technologies in development is that the wood sources are often in remote regions, far from sawmills or paper plants, (said Chuck Hersey, a Washington DNR forest health specialist). Hauling the wood is expensive, so that makes it hard for wood energy to compete against cheap natural gas and hydropower.

One advantage with Amaron’s technology is that the mobile units could be operated in remote areas where the forests are being thinned, Hersey said. Then, only the higher value end products need to be transported away, he said.

This is especially critical in a timber state like Washington, where the federal forests are so mismanaged that the trees are dying from insect infestation and massive wildfires. Mobile fast pyrolysis machines could help make even modest forest thinning pencil out.

The state Department of Natural Resources hosted this (pyrolysis) demonstration because it’s seeking solutions to Eastern Washington’s biggest forest health problem: dense forests in need of thinning to reduce wildfire and disease risks, which is expensive work.

“When we are talking with landowners about how to improve their forest’s health, (it) involves removing small trees and oftentimes that material doesn’t have much of an economic value,” said Chuck Hersey, a DNR forest health specialist who organized the event with a Utah-based company that developed the technology.

“This technology is one potential pathway for dealing with small, low-grade trees,” Hersey said. “It’s basically turning woody biomass into more dense, renewable energy products that have a higher value than just wood products.”

With such massive potential, it’s no wonder that the DNR demonstration last week attracted a large crowd.

While the process and its products are still in development, there’s widespread demand for technology to make the forest thinning economically viable. More than 100 people came to see the biomass reactor in action, mostly forest managers, sawmill operators and renewable energy researchers from around the state, Hersey said.