Refurbished Former Paper Mill in Maine to Send 500,000 Tons of Torrefied Biomass to Europe Each Year

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. _Biomass

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Torrefaction of wood creates a type of "bio-coal" which is more energy dense, water resistant, and more easily co-fired with coal, than ordinary wood pellets or briquettes. The Rotowave technology used in the Maine torrefaction plant

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.

...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.

...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.” _Biomass

NewBiomass
The above chart illustrates the superior energy characteristics of torrefied wood when compared to ordinary wood pellets. Another way of looking at torrefied biomass is as a clean and renewable type of coal, which can be produced anywhere that biomass can grow.

More about torrefied wood:

Grinds Similar to Coal. Torrefied material grinds similar to coal. It can be ground in many existing facilities, easing its integration into existing coal facilities. By comparison, wood pellets are difficult to grind, effectively preventing their use in most existing coal plants without the addition of specially designed grinding and handling equipment.


Burns Similar to Coal. While torrefied wood is a renewable, carbon neutral resource, it burns similar to coal. Certain volatiles and other compounds (hemi-cellulose material contained in wood) are largely eliminated in the torrefaction process, making torrefied materials easier to co-fire in power plants originally designed to use only coal. The change in the chemical composition of wood during torrefaction not only increases the energy density, but also improves the manner in which the wood burns in a coal gasifier, permitting more of the energy to be converted into electricity. This makes the energy content of torrefied wood more valuable. By comparison, wood pellets contain volatile organic compounds that release smoke when burned. These volatiles can create slag or ash in existing coal power plants and restrict the use of wood pellets in such plants. _NewBiomass