Fire and Ice

As temperatures fall and the demand for fuel increases, the challenges for biomass aggregators increase. Two industry veterans talk about what it takes to keep material moving, and fires burning.
By Tim Portz | September 01, 2017

Built into the parking lot of the National Life headquarters in Montpelier, Vermont, are two doors that slide open to reveal a deep bunker where the company receives biomass fuel deliveries, three or four times per week. During winter, the 2,000 employees who work at the facility are warmed by one of Vermont’s largest commercial biomass heating systems, one that, unless replenished with new biomass nearly every other day, will quickly consume all of its fuel and run cold.

Just over 100 miles to the southeast in Henniker, New Hampshire, is Cousineau Forest Products, the company responsible for delivering on-spec woody biomass to those two doors on time, without fail, regardless of what may occur. To complicate matters, no fuel can be delivered to the National Life headquarters between the hours of 7 a.m. and 5 p.m. Even further, the route from Cousineau Forest Products to National Life requires trucks to climb and descend Hogback Mountain. On dry roads, the journey takes less than two hours. In winter, when snow and ice regularly slow or threaten to halt traffic altogether, the journey can be harrowing. It is not uncommon for a delivery driver to stop at the base of Hogback Mountain and wrap chains on the wheels to make the climb. All of this happens against the backdrop of a delivery deadline of 7 a.m., when National Life’s parking lot will begin to fill with workers who expect their offices to be warm and comfortable.

For Curt Richmond, general manager at Cousineau Forest Products, the difficult route to, and restrictive delivery schedule at National Life are a part of a larger package of challenges that are the hallmark of woody biomass collection, handling, storage and delivery during Northeast winters.
Cousineau Forest Products is one of five different family-owned businesses built upon a foundation of the region’s abundant wood supply. The company began as a single location sawmill in 1958; the biomass business unit was launched in 1996. Richmond has been acting as the general manager of the operation since it opened. Through 20 winters, Richmond and his small team have developed a thorough understanding of the challenges and pitfalls associated with handling biomass in winter, mastering the practice keeping the material flowing, regardless of what the weather does.

The biomass Richmond and his team receive, whether in round wood or chipped form, arrives between 40 and 45 percent moisture. Cousineau Forest Products’ job is to produce a material that is 30 to 35 percent moisture, screened to 2-inch-minus with no overs or fines. Each year, Richmond and his team receive, size and deliver over 1 million tons of woody biomass, with the majority of the deliveries occurring during the winter months.

Throughout most of the year, and certainly in winter, Cousineau Forest Products accomplishes this without the aid of any significant long-term storage. Accordingly, Richmond operates Cousineau Forest Products in a just-in-time environment. “I can’t screen this winter’s orders and then store it,” Richmond says.  “I try to bring biomass in and use it quickly. I can handle 10 or 20 loads of raw product without sticking it outside, and 10 or 20 loads of my processed product. For the most part, I’m always looking three days ahead.”

Operating in a just-in-time environment helps Richmond and his team mitigate the challenges that come with snow and ice. If either enters Cousineau Forest Products’ production environment, the impact is felt relatively quickly. “Snow will mix with sawdust and plug screens up,” he says. Far better, Richmond notes, is to do everything possible to keep snow and ice out of the production process altogether.

Managing Mud Season
Keeping snow and ice out of the production environment aren’t the only challenges that winter brings to Cousineau’s biomass business. Winter in the Northeast is bookended by two mud seasons, when wet conditions keep loggers out of the woods, bringing the production of woody biomass to a halt. Wet season in the fall is typically four to five weeks, with a longer season, perhaps even eight weeks, in the spring. To meet its delivery obligations to its customers during those months, Cousineau relies upon reserves of woody material that it accumulates intentionally over the later spring and summer months. “We typically build an inventory of between 6,000 and 8,000 tons of roundwood during summer,” Richmond says. “By January, half of that is gone. Around that time, I start worrying about the spring mud season.”

During these wet seasons, when the flow of biomass coming directly from the forests slows to a halt, Cousineau turns to these reserve inventories, and begins processing roundwood to meet their daily delivery commitments. Cousineau’s reserves, or roundwood, does not sit under any kind of permanent cover, and as a result, snow and ice often need to be removed from logs at the top of the stacks. “If we’re pulling logs shortly after a snowstorm, we might have six inches of snow or ice on some of our logs,” Richmond says. “If you stick that in the chipper, you’ll blow that snow into your chips. When you get snow or ice into your chippers, it’s going to stick to the sides.  We have to go as far as shaking our logs, or dropping them onto the ground, to clear them of snow and ice before we process them.”
Eventually, the fall mud season ends, and the ground in the forests freezes, permitting loggers to once again get into the woods to harvest material. The flow of fresh chips begins again, easing the pressure to satisfy orders by chipping stockpiled roundwood.

Jamie Damman, a North Country Procurement partner who manages biomass inventories for larger biomass power facilities, echoes the relief felt by Richmond. “Logging is really best when there is frozen ground,” he says. “There is not a lot of dirt on the wood, and the loggers can really go.”

Minding the Piles
North Country Procurement differs from Cousineau both in how it does business financially, and the types of customers it services. Rather than buy and later resell biomass to a roster of clients, North Country manages inbound biomass for a smaller roster of clients, predominantly large biomass power facilities, collecting a management fee to do so.

North Country’s customers often maintain larger inventories of biomass onsite, typically storing it in outdoor piles adjacent to the power station. This arrangement offers some advantages, such as building up larger reserves of biomass inventory on-site, but new challenges are introduced, many specifically connected to the piles themselves. “One of our biggest challenges is pile management, or how piles change over time,” Damman says. “If you build a pile and check on it months later, it can be a surprise.”

Damman explains that piles of woody biomass need to breathe and ventilate, or the material will degrade more quickly. He notes that fines tend to accelerate this deterioration. “Fines tend to settle into all of the little crevices within the interior of a pile, making it really difficult for a pile to breathe,” he says. “A crust of snow and ice on a pile just exacerbate this problem.  The worst case scenario is that a pile gets so hot in the interior that it spontaneously combusts. Most of the pile fires I’ve witnessed have occurred in the winter months.”

For Damman, the name of the game is keep the biomass moving, and avoid flat piles that, in a prolonged period of very cold temperatures, could freeze solid. “Get your loaders on top of your piles to break up any crust of ice that forms,” he says. “This keeps the air moving inside of the pile and allows your operators to access material that has not yet frozen.”

While Cousineau and North Country Procurement may approach their business differently, their ultimate goals are the same, maintaining an unobstructed flow of biomass fuel to their customers’ boilers. The onset of winter makes this more critical and more difficult. The flow of material out of the forest is compromised, snow and ice contamination become an issue, and delivery routes are often slowed or altogether closed. All of these challenges are set against a backdrop of peak demand. When winter is at its coldest, the call for biomass fuel is at its peak.

To the credit of Cousineau Forest Products, North Country Procurement or other biomass aggregators, the schools, hospitals and businesses, including National Life, that rely on them are largely unaware of the massive challenges that are overcome to warm and power their operations.

For Richmond, this has become Cousineau Forest Products calling card. “I always tell prospective clients that no one’s fire has ever gone out on our watch.”

Author: Tim Portz
Executive Editor, Biomass Magazine