By Jennifer McCary
By Jennifer McCary
June 8, 2011 - New England Wood Pellet (NEWP) operates two pellet plants and has recently started up a third. The newest facility is located at the former Norbord panel mill site in Deposit, New York.
New England Wood Pellet (NEWP) operates two pellet plants and has recently started up a third. The newest facility is located at the former Norbord panel mill site in Deposit, New York. It will add 100,000 tons/year of capacity, bringing NEWP’s total production to 260,000 tons/year (about 236,000 tonnes/year), making it the region’s oldest and largest producer in operation today. Its other two facilities in Jaffrey, New Hampshire, built in 1999, and in Schuyler, New York, built in 2008, each produce 80,000 tons/year of pellets.
|The Bliss pellet mills at the Schuyler plant are configured radially from a single, central fibre metering bin. Photos: Jennifer McCary
Steve Walker, CEO of NEWP, is an 18-year industry veteran. Now finishing his fifth pellet plant project, the 43-year-old entrepreneur continues to refine the art of making wood pellet fuel.
Recalling the challenges and unpredictability of his first pellet mill ventures in the early 1990s, Walker says, “You would have some days you couldn’t make pellets and some days when you could, but you didn’t know why.” Weather, temperature, wood species, and even the way the wood is ground are among the variables that directly affect pellet making, he explains.
Walker built his first pellet production facility in Acton, Massachusetts, with a capital investment of about $200,000. That operation produced around 2,000 tons of pellets annually. “It was an economic disaster,” he laughs. “The more we made, the more we lost. But I learned a lot. It turned out to be more of a laboratory than a production plant.”
Walker’s second plant was NEWP’s first in Jaffrey. Production and financial performance improved significantly, and Walker could see potential for strong market growth. That site was only permitted for up to 18 hours of daily operation, however, so NEWP purchased a larger parcel across town and relocated to a new facility in 1999. It was permitted to run 24/7. The initial investment in 1996 was $1.5 million. The relocation, plus a series of upgrades, has brought total investment up to $16–17 million.
The latest upgrade at Jaffrey, completed in 2010, was a $3-million update of all electrical systems to improve fire safety and control. All lighting was converted to dust-proof fixtures with low surface temperature enclosures to prevent ignition of airborne dust. The upgrade meets or exceeds the U.S. Occupational Health and Safety Administration (OSHA)’s more stringent enforcement of safety regulations in the wake of various factory dust explosions and fires elsewhere in recent years.
Walker contends that part of the problem in the pellet industry has been that participants are often from a sawmill background and are used to dealing with high-moisture sawdust. Pellet manufacturing deals with a much finer, dryer material that is exceptionally explosive. He equates pellet making with the discipline and process controls of a fuel refinery. He recommends that mill owners seek assistance from a consultant or OSHA (in Canada, the Canadian Centre for Occupational Health and Safety, CCOHS) to make sure all potential hazards and compliance issues are adequately addressed. “If we, as owners, don’t take this seriously, that alone could end a business and end it in a very disastrous way with people getting hurt. That is inexcusable,” he says.
As the demand for pellet fuel grew, NEWP began to expand, starting up its Schuyler facility in 2008. It has proximity to the wood resource, easy highway access, and consumer markets in major metropolitan areas in Pennsylvania, New York, and New Jersey.
|The Schuyler plant started producing in 2008.
Walker is a self-taught engineer and has done all the engineering and design for each plant. Much of the pellet mills’ material handling and emission control systems have been designed and fabricated at NEWP’s fabrication shop in Jaffrey, which was built in 2006. That shop has helped to reduce project costs, keeping the total investment in the Schuyler plant at $13 million.
The mill is currently operating on a 24-hour, five-day workweek with a three-man team per shift. Green and dry chips and sawdust are purchased from local mills. Arriving trucks cross a Fairbanks scale and unload at a Peerless truck dump. Operator Rick Waterbury uses a Volvo L110 bucket loader to carefully blend raw materials to achieve the right proportion of hardwood chips, green sawdust, pallet grindings, softwood, and other dry trimmings. Targeted moisture content for the blended material is in the mid-30% range, and the feedstock is stored under cover to maintain that level. Moisture is measured several times throughout processing to ensure proper levels for binding quality pellets.
A live floor infeed delivers the material to a conveyor belt, which passes under a large Industrial Magnetics magnet and through BM&M shaker screens to remove oversized wood slabs and fines. Oversize wood is ground and used in pellet production, whereas the fines feed the biomass furnace that supplies process heat for the dryer.
The pellet feedstock is processed by a 500-hp Bliss hammermill, which grinds it into a uniform pea size. The material then enters an M-E-C triple-pass dryer capable of drying about 10 tons/hour. Targeted moisture content at the dryer outfeed is 15%. Fines are removed by two Kice cyclones, and the dry feedstock is stored in two storage silos. The storage silos were built in-house to address previous issues with frozen wood and concerns about meeting safety codes. The units feature a metering system and robust silo motors that continuously mix the contents.
Dried wood that is purchased from local sawmills and furniture and flooring factories goes directly to two storage silos. Reclaimers incorporated with each silo feed the fibre into a 500-hp Bliss hammermill for final sizing.
From storage and initial processing, the fibre enters a large distribution bin, where augers distribute it to each of three Bliss pellet mills. Drag chain conveyors deliver the pellets to the cooling tower and then to the pellet storage silo. Fines and oversized pellets are removed by a BM&M shaker screen before the pellets go to the automatic Hamer bagging system. Filled bags fall to a conveyor belt on the packaging line that’s equipped with a Conveying Industries EC-201 Fuji Ace robot stacker and a Wulftec shrink-wrap palletizer turntable.
The 30,000-square-foot facility is protected by a Firefly fire detection/prevention system with spark detection and fire extinguishing capabilities. When sensors located throughout the process detect a fire, alarms sound, and the system automatically starts backing everything out of the building, where small amounts of water are sprayed to put the fire out.
In 2009, Walker received a call from Norbord, which had determined that its aging mill in Deposit was no longer economically viable and would have to be closed. Norbord went the extra mile to seek out prospective buyers who would continue to manufacture a wood product to try to save as many jobs as possible and also keep the established wood supply chain intact. NEWP purchased the mill in late 2009, barely more than a year from startup of the state-of-the-art Schuyler plant, and hired 20 of Norbord’s workforce well in advance of project construction and completion. Walker says the community has been excellent to work with and very supportive of trying to save the plant.
|Steve Walker is CEO of New England Wood Pellet.
“Getting this built-in team was a major deciding factor in taking on this old facility,” states Walker. “It takes a long time to get a group of people to operate a complex plant, so I was really excited to have them.” None of the previous plant’s machinery, including the flash tube dryer, was used in the new pellet mill. Much of the physical facilities and equipment were sold, scrapped, or torn down. About the only thing left is the forming line and 200,000 square feet of buildings that are used as warehouse space.
The new plant has several innovative design features, especially in safety and cost efficiency. The mill floor is a compact layout housing an M-E-C triple-pass dryer, two 500-hp Bliss hammermills, four Andritz pellet mills, an automated Hamer bagger, and a Wulftec shrink-wrap turntable. Only the plastic covering is manually positioned onto the stacked pallet before it enters the Wulftec system.
Key design improvements include a Wellons furnace with an oversized dryer that allows a reduced drying temperature of just 315°C. This is considerably lower than in conventional drum dryers, which helps reduce volatile organic compound emissions. The in-house fabricated storage silos have fabric tops that allow the cloth to disintegrate in the event of an explosion and prevent structural damage to the storage cylinder. A Kice baghouse and six customized Fisher Klosterman cyclones help the plant meet New York’s stringent emissions permit requirements.
NEWP worked with equipment vendors to incorporate a centralized process control system that manages every motor and control throughout the plant. Standard machine controls were either eliminated or bypassed so that one system controls the entire plant and there are no communication problems from one machine to the next. “We did this basically for mill uniformity and simplicity to make it easier to learn, easier to maintain, and cheaper to maintain,” says Walker. “But it is definitely not cheaper to put in.”
In contrast to the Schuyler facility, each Andritz pellet mill has an in-house fabricated metering bin above it and a cooling box below it. Walker says that having the cooler below the pellet mill is safer because it eliminates dock and chute conveyors and the spark detectors normally needed when conveying hot pellets to a central cooling tower. Fires can occur in the cooler, and Walker says that he would prefer to deal with containing one to a cooler that is one-quarter the size and mated to its own cyclone.
This combination of metering bin, pellet mill, and cooler is also more economical. It helps keep the required enclosed space to a minimum for a more compact and cost-efficient layout. In addition, large windows reduce or eliminate lighting requirements during the day. Keeping costs in line is mandatory if the industry is to remain competitive with other energy sources.
The company markets its bagged and bulk delivery services in a two-step distribution channel geared to consumer consumption in the Northeastern United States.
Jennifer McCary is senior associate editor of Wood Bioenergy. This article originally appeared in Wood Bioenergy, first quarter 2011, and was reprinted here with permission.