THE MAGAZINE DEVOTED TO NICKEL AND ITS APPLICATIONS
June 2008
Volume 23, Number 3
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Buckman Canada, in Vaudreuil-Dorion, Quebec, have built and shipped some 1,000 feed delivery
systems in the past 10 years. Most are made of nickel-containing S30400 and S31600, though sometimes S31603 is selected for its resistance to particularly corrosive chemicals.
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Nickel stainless steels provide reliable service in delivering a wide range of chemicals
By Carrol McCormick
Nickel Magazine, June 2008 -- Pulp and paper mills use many speciality
chemical additives in the process of creating the paper products we use every day. These chemicals control
undesirable conditions such as foam, the growth of biocidal slimes, the pitch introduced by some wood
species, and sticky substances from recycled cardboard.
Left untreated, these conditions can produce defects in the finished product as well as increasing energy
costs and forcing mill operators to use more chemicals such as bleach. Other speciality chemicals are added
to treat mill water both before and after its use in paper making, thereby reducing corrosion in boilers and
preventing scale build-up on heat transfer surfaces.
Mills have many feed systems that deliver these chemicals in precise quantities at strategic stages for
wet-end management and water treatment. The feed systems must resist aggressive chemical components such as
solvents, acids and bases, and corrosive biocides, as well as provide years of maintenance-free,
round-the-clock service and ensure the safety of mill workers.
Buckman Canada, in Vaudreuil-Dorion, Quebec, and its suppliers have built and shipped some 1,000 feed
delivery systems in the past 10 years. Most are made of nickel-containing S30400 and S31600, though sometimes S31603 is selected for its resistance to particularly corrosive chemicals.
Materials such as ABS plastic, brass, rubber, aluminum and fibreglass-reinforced plastic provide
satisfactory resistance against some chemicals. However, certain other chemicals will swell, cloud, soften,
harden, corrode or completely destroy these materials.
Buckman prefers S30400 and S31600 because they are compatible with most of the company’s products and
because using them simplifies both design and inventory management. “These two stainless steel types cover
most of our requirements,” says Peter Campisi, who runs Buckman’s equipment department.
“Ideally we would hope to never have to repair or replace equipment,” Campisi says, but adds that a
service life of five years is likely in most cases, owing to the effects of the chemicals used, frequency of
usage, and various environmental factors.
“We try to get as close to zero maintenance as possible, which usually means spending more money up-front.
In the long term, this trade-off is worth it, which is why we mostly use S31600 as a standard, even when we
could use less expensive alternatives.”
For the mills, another advantage is that corrosion-resistant stainless steel construction is less prone to
leaks which gives workers improved safety conditions while reducing chemical loss to the environment.
Carroll McCormick is a Montreal-based freelance writer.
Photos: Buckman Canada
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