Biomass heater boosts energy efficiency
November 18, 2013 | 6:00 pm CST

Vanguard Inc. operates an efficient operation, making countertops, store fixtures and commercial cabinets.

The company looked closely at its own building, investing in a biomass heater that cut energy and landfill costs sharply. Vanguard president Brian Gilligan has made other green changes, and even has a solar panel project on the drawing board.

The Dubuque, Iowa, company has made laminated and solid surface countertops (polyesters, acrylics, and blends) for more than 50 years. Gilligan says the company stumbled into the store fixture business while doing a buildout of a local retailer.

“The retailer was simultaneously unloading store fixtures that were quite similar to what we were unloading, and the light went on,” he says. “We landed that account after more than a year of working on it, and have gone on to do projects for more than 20 companies from large to small. Names include Wal-Mart, JC Penney, Kohl’s, Flexsteel, Trek Bicycles, Wrangler, Crescent Electric, Verena St. Coffee, Theisens, and many more.”

Gilligan says that Vanguard approaches the manufacturing process differently than a traditional store fixture manufacturer. “Because of our roots in countertops and commercial cabinets, we have a more technical/engineering-driven approach as opposed to a design/aesthetic approach. This manifests itself in a higher quality product, more structural integrity, and more robust design.”

Vanguard has also made commercial cabinets for many years. “We modified our design and process to optimize our equipment and workforce,” Gilligan says. “Guided by the 32mm system, we were able to take as much as 65 percent of the labor out of the process and increase the quality and consistency. We are not craftsmen, crafting a cabinet. We are manufacturers, manufacturing a cabinet.”

Vanguard’s plant floor in Dubuque includes examples of modular store fixture displays of various sizes and designs, and a small low-cost “e-tailing display.”

There is plenty of room for a C.R. Onsrud Panel Pro CNC router, which Gilligan says fits into their operation well. Also here is a Midwest Automation saw, Holz-Her vertical panel saw, Accu-Systems HPJ dowel inserter, Holz-Her Spring 1320 edgebander and Uhlig HP3000 case clamp.

The setup here is efficient, but Gilligan saw one area that could be improved. “I had read articles for years that the Europeans were using wood waste for heat, and I had watched the landfill costs increase each year, so eventually I decided to do something about it,” he says.

“I attended the Stiles Executive Briefing Conference in Princeton, N.J., where this technology was going to be highlighted and learned what I needed to know. I met Ron Kirkendorfer of Northline Energy and we went from there.

In the fall of 2009, Vanguard installed an 800,000 BTU Biomass Combustion System. To automate the process, which was necessary to reduce the labor-intensive task of filling the furnace, they installed a grinder, holding bunker, and an automatic feed system.

“Scraps of particleboard, wood, melamine, and particleboard with P-lam are stored in small carts at several areas in the shop where scrap is generated,” Gilligan explains. “The carts are the equivalent in size of the grinder hopper (a Weima low-speed shredder is used). When the cart is full we roll it over to the grinder and empty the cart into the grinder hopper.

“We then push the start button and the grinder begins to grind the scrap. The control box has a timer in it and it shuts the grinder off in a pre-determined time frame which correlates to the length of time to grind an average hopper full.”

The operator used to throw this scrap in a dumpster that was headed for the landfill, so the labor is about the same. The grinder then does its job and grinds the wood waste, which falls through a 1-inch screen and is picked up by an auger.

In the winter, the auger fills the bunker directly. In the summer, when the furnace is not running, the auger fills bags that are stored for use in the winter. Bagged wood chips are stored in large bags on a pallet rack.

At the bottom of the bunker, an unloader using sweep arms pushes the fuel to an auger which moves material out of the bunker, through a rotary air lock device, and then into a final auger into the back of the fire box of the furnace itself.

The furnace is not a typical wood burner. Its control panel is made up of a series of programmable logic controllers and limit switches, with sensors to keep the system operating safely. The fuel is augered into the box, the heat of the furnace makes the wood fuel off gas, the gas is allowed to “resonate” in the large fire box and in the afterburner chamber which is a necessary step to fully burn the gas and eliminate emissions. What is left is heated air. This air moves through a series of tubes that pick up the heat and is then power vented up the exhaust stack.

“The efficiency of the system is about 70 percent,” Gilligan says. “But since the fuel is free, efficiency is the not the driving factor in this system.”

A temperature-controlled fan pulls room air in through the lower back of the furnace, up through the heated tubes and blows the warmed air in the room until the temperature reaches a lower-preset level and the fan shuts down. This process repeats itself as the tubes (heat exchanger) heat up again.

Biomass Combustion Systems in Worcester, Mass., made the furnace. Most gasses are recovered, and the amount of smoke is very small, but they had to make adjustments along the way to get it just right. There is a six-and-a-half year payback on the furnace.


By the numbers:


76 million BTUs : the fuel value represented in one bunker full of wood waste
10 barrels of oil is the equivalent of this bunker full of waste
68 cubic yards of wood waste is the capacity of the bunker
$45 is the monthly heating bill for the 30,000 sq. ft. plant
$86,748 is the cost of the system
840 lbs. of wood waste is burned each day for six months
150,000 lbs. of wood waste is diverted from the landfill and used for heat each year




The biggest challenge in setting up the system was developing the proper settings so the wood waste would burn at the required rate. Too fast meant the fuel would not sustain temperature and fire, too slow resulted in emissions. With variable settings for feed rates in, under fire air, over fire make-up air, exhaust fan rate, all these variables make the process adaptable to any specific fuel, however the flip side of that coin is finding the sweet spot, which can take some time.


Gilligan says that patience was needed, and keeping a log of every change and mapping the process is vital to achieving a system that runs just right.


“I had great resources in Ron Kirkendorfer of Northline Energy, and Charlie Carey and Russ Samara of Biomass Combustions Systems,” he says. “They taught me to understand the cause and effect of every adjustment in the system, and by doing so, taught me more about combustion than I ever wanted to know, but allowed me to become very familiar with this system.”


The time and effort has paid off for Vanguard, both in reduced heating bills and an improved environment.

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About the author
Karl Forth

Karl D. Forth is online editor for CCI Media. He also writes news and feature stories in FDMC Magazine, in addition to newsletters and custom publishing projects. He is also involved in event organization, and compiles the annual FDM 300 list of industry leaders. He can be reached at [email protected].