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Potomac Supply Corp. Wins Environmental Award, Utilizes Green Energy
Potomac Supply: Virginia sawmill business wins environmental award for its latest development –processing residuals into biomass fuel that is burned to produce steam for lumber dry kilns.
By Chaille Brindley
Date Posted: 9/1/2008
Operating a ‘green’ facility is nothing new to Potomac Supply Corp. in
All the logs processed at
Biomass is green in more ways than one.
William (Bill) Carden Jr.,
Redesigning Drying Operations
The heart of the new kiln operation is a wood-waste dry wood fuel burner developed by McConnell Industries Inc. of Birmingham, Ala. Clifford T. McConnell is a pioneer in the area of biomass combustion. He installed his first dry wood-fuel burner in 1974 during the Arab oil embargo. After studying the market,
The McConnell Energy System utilizes the latest technology in control instrumentation and digital displays, which allows for monitoring the lumber drying process in multiple zones throughout the kilns. It has rapid response to control signals. This allows for the use of a short flame with a completely clean burn. Finally, the system incorporates a cyclonic suspension type, dual-chambered combustor in which dry fuel is converted to heat energy with a conversion efficiency equal to that of fossil fuel burners. The moisture content of the wood fuel processed is less than 15%, and it is finely processed into particles about 1/8-inch in diameter.
The fuel processing system is what distinguishes
Once unloaded, biomass is processed through a hammermill to ensure consistency for the bio-fuel. The system is equipped with a Flamex spark detection system. Cliff said, “When you have dry fuel, you always have the chance for a fire. That is why we included the spark detection in our system.”
Magnets are placed near the hammermill to pick up any stray metal in the biomass. If the system detects a spark, it automatically shuts down and sprays water on the problem areas. This material is then kicked out to a waste bin to keep it from entering the silos.
Koger Air supplied the air handling system for the new fuel system and kilns – blower, cyclones, duct work and air handling system.
Lowell Thomas, owner of National Barn Co. NE said, “We offer customers a cost effective way to get the building they want.” Pole design construction helps reduce cost and increase the flexibility of the structures.
National Barn has been a
Cliff said that
Cliff said, “It was a turnkey job. They had a good crew come on and did a good job.”
Looking to save money wherever possible,
Programmable logic controls (PLCs) take very accurate readings to keep the system running as efficiently as possible.
Switching from propane to biomass energy was not that difficult.
The biggest thing to ensure a smooth transition was keeping all the duct work the same size and air flow capacity as the old system.
Cliff said, “
Unitemp Dry Kiln of
“We don’t have standard advertised models. We work with our customers to meet their specifications,” said Jerry.
Cliff explained, “Signature’s SmartTrac looked to be the most user friendly product. It was in a price range that was reasonable. And the biggest selling point was that Signature’s kiln monitoring system interfaced with our NMI moisture measurement system. This allows you to track lumber after it comes out of the kiln and passes through heads to the planer mill.”
With over 300 installations around the world, SCS claims its technology can help improve yield. According to SCS, better moisture control combined with end-to-end data integration can result in a 4% or greater improvement in moisture grade.
Improved moisture control has emerged as a critical process improvement in the forest products industry as mills increasingly focus on profitability and yield. Adding NMI’s widely adopted sawmill and planer mill digital pulse moisture measurement technology to SCS’s in-kiln dielectric moisture measurement product line, offers the industry the first digitally integrated, end-to-end moisture measurement solution.
Cliff said, “You used to dry lumber by the seat of your pants. You used to dry lumber based on time and watching the dry bulb temperatures and looking for a wet bulb drop. Then companies started using drop across-the-load control methods. Now moisture meters have evolved to the point that the technology has become dependable while offering better results.”
Although there is a learning curve with the software, Cliff said the charts give you a good idea of what the kiln is doing. SmartTrac technicians can adjust the system remotely while providing technical support.
Cliff said, “It has taken us a couple of months to get everything calibrated so that you feel safe with it. We have gone from the stone age to the 21st century as far as drying techniques.”
He further explained, “Accuracy gives you efficiency. That means it requires less energy to dry. You are less likely to over dry or have wet lumber coming out since the data is more accurate.”
Plans for Future
Two years ago
Pioneered by Andy Pollard of Pollard Lumber Co. Inc. in
Rich said that
Rich said, “At this point, the kilns we have are keeping up with production. When the market changes and we have the production capacity needs to justify it, we will probably convert the last kiln over to the continuous drying process.”
The fourth stage would catapult
Bill said, “A significant percentage of biomass in the
Bill said, “There is a critical need for critical mass. Without other people getting into this business, there is no real opportunity.”