Editor's Note: This article is a preview of a larger roundtable feature on fiber raw materials that will appear in Solutions! later in the year. The roundtable is sponsored by the TAPPI MOTAG South group.

The "holy grail" in fiber raw materials is producing uniform wood chips for the pulp digester. Uniform chips would dramatically increase productivity and lower operating costs. However, reaching that goal will require a lot of hard work.

"The most challenging chip quality need we face is when a pulp mill has a unique optimal chip distribution," said Billy Watson, director of fiber utilization, wood and fiber procurement for Georgia-Pacific Corp., Louisville, Mississippi, USA. "If a mill prefers a bigger or smaller chip than all of the other mills in a basin, chip suppliers must either change set ups according to the pulp mill they are shipping to, or the supplier must hit a middle ground in set up that is not truly optimal to either mill. We do have some satellite chip mills that change set-ups as they switch their production to different mills. This is time consuming and costly, but it is possible."

Watson noted that Georgia-Pacific is working with all of the suppliers shipping chips to its pulp mills. "We help them with each chip-producing machine center and give recommendations on what is needed to get the best chip out of each machine," he said. "Our motto is to chip to quality rather than screen to quality. With this approach, we get better chips and the supplier produces more chips out of the raw material he has purchased."

NEW TECHNOLOGY?

New kraft pulping systems are also changing the size distribution that pulp mills need, and digester suppliers are not yet sure what that size distribution looks like, according to Bill Fuller, president of FRM Consulting, Federal Way, Washington. "There is an important need for new research to establish optimum size distribution," he said. "There is a general feeling that the chips must be larger, but how much larger?"

One of the challenges to establishing optimum size distribution is that a higher percentage of wood chips are coming from sawmill residuals. "When sawmills are balancing demand for smooth surface, high yield lumber against chip size, lumber quality will win every time," said Fuller. "It will be a challenge to find that optimum size distribution so that systems can be appropriately modified."

Fuller believes that the industry must fund new research on chip size distribution. Since there are fewer research organizations than there were a decade ago, it is likely that this research will need to be done on a cooperative basis.

"Coming up with the research funds will not be easy, but there are facilities such as The Herty Foundation in Savannah, Georgia and Econotech in Vancouver, British Columbia that could do the work with the cooperation of other organizations and interested suppliers," he said.

Without this type of research, the industry will continue to sub-optimize its pulp mills and operate at higher costs, said Fuller. "Establishing optimum chip size distribution would improve productivity in the digester and produce better product uniformity," he said. "We could easily come up with a 5-10% increase in digester production."

RESEARCH PRECEDENTS

Fuller pointed out that this type of cooperative fiber raw material research has been successful in the past. For example, in the late 1970s a comprehensive cooperative study of chip pile deterioration led to new storage methods and treatments that helped prevent deterioration and chip pile fires. Another example is past research into whole tree utilization. The results of these studies are still being used today to preserve chip quality and supply mills with thinnings and increased wood recovery in harvesting, said Fuller.

"If we can save a buck a ton on every load of chips going into a digester, the added benefits of improved product quality and productivity will easily justify the capital spending that many older pulpwood systems desperately need," he concluded.

ALAN ROOKS, EDITORIAL DIRECTOR

ABOUT THE AUTHOR

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Alan Rooks is Editorial Director of Solutions! magazine. Contact Alan at +1 847 998-8093, or by email at: arooks@solutionsmagazine.org.