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Converting low value …to High Value

A Peterson 5900 disc chipper—the first 5900 machine in B.C.—is proving to be a consistent and reliable converter of low value pine beetle-ravaged timber into high value wood chips in the B.C. Interior.

By Jim Stirling

Ian Gibson (right), northern sales manager with Peterson dealer, Woodland Equipment, and Mark Boisvert, product specialist with Woodland Equipment, with the Peterson 5900 disc chipper, which is now producing chips for the Paper Excellence pulp mill in Mackenzie, B.C.

Out at the Windy Point Reload, the Peterson 5900 disc chipper was delivering what it promises. The machine was processing low grade predominantly lodgepole pine beetle-ravaged timber and converting it to high value chips. The chips were destined for Paper Excellence’s pulp mill at nearby Mackenzie, in north central British Columbia.

Paper Excellence’s acquisition of the machine represents the first deployment of a Peterson 5900 chipper in B.C. The machine was proving itself a good fit.

One advantage the 5900 brings to its task is versatility. “It has a large feed throat and is capable of accepting a tree up to 24 inches in diameter, as well as multiple smaller diameter stems,” explained Mark Boisvert, the Peterson product specialist with equipment dealer Woodland Equipment Inc., based in Vernon, B.C.

The feed system for the woody material uses upper and lower direct feed rolls which can operate at speeds up to 47 metres/minute.

Within its approximately 30 foot length, the 5900 machine converts a broad diet of raw material into wood chips of specified lengths. The machine’s standard three pocket disc produces chips from 3/4 inch to 1.25 inches in length. The optional four pocket disc can deliver chips from one half-inch length to one inch.

Key to the process is Peterson’s heavy duty chipper disc (66 inches in diameter and nearly five inches thick) to help mesh high production with consistent chip quality.

The word ‘consistent’ crops up a lot in discussions about chipping machines. Chips for use in pulp mills must be the required size, thickness and consistency, said Boisvert. When that quality of chip is achieved on a consistent basis, it leads to a more even baking of the process chemicals in the pulping system, he continued. “The four knife disc option in the chipper means it can operate faster but you don’t want to alter the consistency of the chip,” he continued.

The challenge lies in balancing speed without compromising chip quality.

Limiting bark content to meet the mills’ tightly prescribed parameters is a further challenge for the pulp making process. Boisvert noted wood types vary but the drier wood consistent with bug killed timber usually makes bark easier to remove.

The Peterson 5900 processes low grade predominantly lodgepole pine beetle-ravaged timber and converts it to high value chips for the Paper Excellence pulp mill at nearby Mackenzie, in north central British Columbia. The chipper is remotely operated through a 12 channel radio.

The Peterson 5900 is powered by a fuel efficient six cylinder Cat C18 engine. Further fuel economies can be achieved through the Peterson’s cooling system which adjusts the pitch of a Flexxaire fan to match engine cooling requirements. Cooling air is directed over the engine to reduce dust build up.

The chipper also has an IQAN adaptive control system. Boisvert called it “the brain” of the machine as it helps regulate the hydraulic and engine functions on the 5900 and contributes to a troubleshooting, self-diagnostic function.

He said the machine has been designed for easy servicing with spaced access platforms for routine maintenance functions.

Choosing the right time to sharpen the 5900’s knives is a further factor influencing chip quality and consistency, continued Boisvert. “The key is not to waste fibre.” He estimated the knife change process takes about 15 to 20 minutes.

The 5900 is remotely operated through a 12 channel radio, he added, and is a mobile unit weighing around 46,600 pounds.

Mac Anderson is general manager of Mackenzie Fibre, a corporation owned by Paper Excellence Canada and a private group of local investors.

One advantage the 5900 brings to its task is versatility. It has a large feed throat and is capable of accepting a tree up to 24 inches in diameter, as well as multiple smaller diameter stems. The feed system for the woody material uses upper and lower direct feed rolls which can operate at speeds up to 47 metres/minute.

Mackenzie Fibre’s raison d’etre is to provide Paper Excellence’s Mackenzie pulp mill with access to the region’s fibre resources, explained Anderson. “We manage a forest licence, awarded to the McLeod Lake Indian Band, but we have no sawmill. We use sawlog sales to leverage fibre sales for the pulp mill.”

To help it achieve that, Mackenzie Fibre operates three regional sort yards, including the Windy Point Reload where the Peterson 5900 was working.

“Fibre for the 5900 right now is about 85 per cent softwood and 15 per cent aspen,” explained Anderson, “with about 80 per cent of that coming from the licence we manage.”

Salvaging the pine killed by the beetle is a licence priority and as a result there’s a 70 per cent diet of dead wood for the Peterson 5900. Anderson said bark content permitted for the Mackenzie pulp mill is typically under 0.5 per cent while the chip sizes required correspond with the mill’s seven and 16 millimetre screen sizes. Material like oversize and fines are screened out.

Ideally a target production for the chipper is 36 oven dried tonnes an hour

“We’re a long ways off that,” said Anderson. That speaks to the debarking systems set up ahead of the Peterson 5900 chipper. Anderson said the latest addition, a rotary debarking system, has experienced start-up issues which have resulted in the Peterson having mainly inconsistent, stop-start periods of log supply with which to work.

“It’s been lots of work and slow progress.” But when it’s had the opportunity, the 5900 has shown it can keep up, noted Anderson. “It has lived up to our expectations so far.”