Isobord Enterprises seeks to lead a new industrial panel revolution with its strawboard products.

If there is money to be made from converting waste straw into industrial panels, then Isobord Enterprises Inc. is positioning itself to be one of strawboard’s biggest profiters.

Located in Elie, Manitoba, 20 minutes west of Winnipeg, Isobord is the largest strawboard plant in the Western Hemisphere. Company officials say more than 40,000 square feet of product have been shipped since August 8, 1998.

Bales of straw, each weighing about 1,200 pounds, enter one of four bale breaking stations. This is the first step in the straw-to-strawboard conversion process.

While not yet operating at its full annual capacity of 144,000 board feet (3/4-inch basis), enthused Isobord executives say they are already developing plans to build a second strawboard plant in 2000 and a third one in 2001. If all goes well, up to three more plants could be constructed during the first decade of the 21st century. In addition, Isobord is exploring immediate options for laminating and milling its Isobord product in Canada.

A Wood Alternative
Isobord officials tout their products as an alternative to wood-based composite panels, in particular particleboard and medium density fiberboard. The most obvious difference is that Isobord, made with finely chopped wheat straw bonded by a methyl di-isocyanate resin, replaces the wood fiber/urea formaldehyde recipe most commonly used to make particleboard and MDF.

Dick Duquette, vice president of production, says early experiments using urea formaldehyde resins with straw were unsuccessful. He says further testing proved that methyl di-isocyanate is better able to adhere with straw’s natural waxy texture.

Fred Thompson, CEO and president, says Isobord’s mechanical properties are superior to particleboard and as good as mid-grade MDF. The company claims a 3/4-inch, 4-foot by 8-foot sheet of its product, with an average density of 40 pounds, is about 10 percent lighter than a similarly dimensioned sheet of particleboard. In addition, the company says its strawboard is more moisture resistant, has an internal bond strength of 90 psi and a screw hold of 250 pounds on the face and 230 pounds on the edge.

Initial customers include manufacturers of ready-to-assemble furniture, store fixtures, countertops and stage sets. In addition, Isobord has developed a couple of products being sold under its own brand name at North American home center stores. The company’s StorageBords are 2-foot by 4-foot tongue-and-groove strawboard panels that install to attic floor joists. Isobord’s second retail product, ShelfBord, comes in various lengths and widths in either 5/8- or 3/4-inch thicknesses.

“We’re still in a period of discovery about our product’s uses,” Thompson says. “Our thinking is still out of the box today.”

Isobord recently began shipping StorageBord, 2-foot by 4-foot tongue-and-groove strawboard panels bearing its own trade name, to North American home centers.

After the Harvest
At full capacity, 400,000 bales of wheat straw will be required to meet Isobord’s one-year manufacturing supply. Each of the bales is 4 feet wide by 4 feet high by 8 feet long and weighs about 1,200 pounds.

To guarantee its massive straw supply, Isobord struck a deal with the Straw Producers Co-op of Manitoba, a group of 350 area farmers formed in 1997. Through this win-win relationship, Isobord pays the farmers for the privilege of accessing their land to gather and bale the residue straw left after the summer wheat harvest.

Isobord operates a fleet of 38 Caterpillar tractors, dispatched via global positioning satellites, to collect and bale the straw within a 50-mile radius of its plant. The bales, collected in August and September, represent a year’s worth of raw material supply. They are stored outside the plant in long, neat rows.

Perhaps even more important than the income they earn for their straw, the co-op farmers are spared the trouble and expense of having to dispose of the waste. Historically, the farmers burned the stubble, creating thick black plumes that polluted the air. In recent years, though, the Manitoba government has cracked down on the harvest burnings, leaving farmers with the arduous task of turning the straw back into their fields.

Isobord officials calculate that the company will help remove up to 200,000 potential burn acres from the annual harvest cycle when the plant achieves full capacity.

Isobord officials say a 3/4-inch, 4-foot by 8-foot sheet of its strawboard weighs about 10 percent less than wood-based particleboard.

Plant Tour
The Isobord operation, including research and development of the panel recipe, represents a $150 million investment, Thompson says. The manufacturing process was designed, engineered and largely supplied by Kvaerner Panel Systems. Stone & Webster served as the general contractor. About 100 people are employed at the 215,000-square-foot plant. Another 100 seasonal workers help with the fall straw collection.

For the most part, Isobord’s continuous strawboard manufacturing process incorporates much of the same refining, blending, forming and pressing technology used to produce particleboard or MDF.

The process begins at an indoor storage area. Here, up to 1,000 bales of straw are stored at a time, enough material to meet a day’s worth of production. The bales are transported by conveyor to one of four bale breaking lines each followed by a hammermill that chops the straw into fine 2-inch-long strips.

The chopped straw is taken by pneumatic conveyor through a series of screens to filter out dirt, rocks and other debris from the material. The clean material is fed into one of two Kvaerner triple-pass driers that reduce the moisture content of the straw from 15 to 20 percent to 3 to 5 percent.

Once it is dried, the material is hogged in Pallmann refiners and converted into fibers. The finer particles are separated for use as the surface material and the larger fibers are used for cores. The separated materials are then fed into storage bins and weighed prior to blending with the resin. (Isobord officials decline to divulge the ratio of fiber and MDI resin from Dow Chemical that is mixed together in the blending process.)

In the manufacture of 3/4-inch panels, an 80mm-high pile of resin is formed on a 10-foot-wide sheet of Kraft paper. The coarser core materials, representing about 40 percent of the panel, are sandwiched between the finer fibers used for the top and bottom surfaces. The formed fiber is converted into panels on a 135-foot-long Dieffenbacher continuous press that operates at 120C and applies about 240 bars of hydraulic pressure, according to Plant Manager Wayne Seymour.

As it exits the press, the continuous ribbon of strawboard is cut into 24- or 30-foot-long sheets by an angular saw. These sheets are then individually fed into an air cooling station.

Once the boards have sufficiently cooled, they are fed into a six-head Globe sander that has a 40-60-80 grit sequence. After the panel is sanded, a process which includes sanding off the Kraft paper, it is cut to length by an in-line saw.