Maine biomass plant will house novel torrefaction technology

By Luke Geiver | December 08, 2011

Thermogen Industries, a technology developer and manufacturer operated by New Hampshire-based investment firm Cate Street Capital Inc., is bringing a microwave-based woody biomass torrefaction technology to Maine.

The technology, created by U.K. firm Rotowave Ltd., uses a series of simultaneous electromagnetic frequencies in combination with a ceramic drum to maximize heat transfer throughout every biomass particle in the unit, making the process of pyrolysis used to turn woody biomass into a biocoal product more efficient. Richard Cyr, senior vice president for Cate Street Capital, said the licensing agreement between Rotowave and Thermogen happened after years of extensive research and planning, and by November 2012, Thermogen hopes to have roughly six Rotowave torrefaction units up and running at a biomass facility in Maine.

“We’ve been looking for a home for Thermogen for a couple of years now,” Cyr said. “We’ve been looking for the right technology.” Thermogen found a home for its new scalable technology in an idled paper mill in Millinocket, Maine. As Cyr explained, Maine Gov. Paul LePage asked if Thermogen would be interested in the Millinocket mill. “We said we weren’t really in the papermaking business.” But, after touring the facility, Cyr said Thermogen found the infrastructure and the available woodbasket to be just what it was looking for.

Over the next 10 months, the team at Thermogen will engineer the plans for the mill to house the necessary infrastructure for five to six Rotowave units, each of which can process 100,000 tons of woody biomass per year. The torrefied product will then be shipped to Europe, Cyr said. “We would be happy to sell to the U.S. or Canada,” he said. But because several European utilities were more aggressive in securing contracts with the company, it chose to sell overseas. “If there was an interest (in the U.S., and there definitely is, we would prefer to sell it here,” Cyr said. “It is cheaper.”

While the goal of the company is to export its biocoal product by the end of 2012, Cyr also said the Rotowave technology has never been scaled up and the facility in Maine will act as a testing ground for the microwave technology. Cyr, however, isn’t at all concerned about the uncertainty surrounding a commercial version of the technology that, according to Rotowave, creates a product that has a bulk density of 750 kilograms per cubic meter, energy density of 18 gigajoules per cubic meter, and an electrical output of 6.67 megawatt hours per ton. “There is an old military expression that an 80 percent business solution today is better than a hundred percent solution tomorrow…when it comes to the environment and ways to cut down greenhouse gas emissions, an 80 percent solution is fine.”

Cyr also hopes past work completed by Cate Street Capital’s water remediation company CleanRunner will act as an example of what to expect with their efforts to commercialize the Rotowave technology. CleanRunner created a water reclamation treatment technology for the drilling processes practiced by the oil and gas industry that was first used in Wyoming at a facility the company named Red Desert. “The oil and gas industry was skeptical that we could do what we promised, that we could clean the water to the level they needed it cleaned to on a high enough volume basis.” Today, Cyr said, the technology is being sold all over the country and used in drilling processes.

The Rotowave process can reduce moisture content to less than 4 percent by weight and increase the energy content in the biomass by 30 percent, according to the company. The process is referred to as a Targeted Intelligent Energy System, and overcomes the inhibiting effect of thermal conductivity in biomass by using the microwaves to interact with the bimoass’ molecular structure. So, the company explains, “the size of the particle has no influence on the reaction time or on the degree of pyrolysis which is aimed exclusively at attaining the necessary increase in calorific value of the solid.”

In early October, Cate Street Capital held a groundbreaking ceremony for a 75 MW biomass facility in New Hampshire it had purchased for $275 million.