1. Case History
16 PULP & PAPER CANADA November/December 2014 www.pulpandpapercanada.com
Photo:Kadant
It’s an ideal situation if a paper or board
mill project aimed at reliability and
improved machine operation can have a
cascading, positive effect on the operat-
ing costs in other mill departments. The
ROI effect is thus amplified. That sort of
scenario was realized earlier this year at
Sonoco’s Trent Valley mill in the hamlet of
Glen Miller, Ont. A board machine dryer-
section project to solve chronic syphon reli-
ability and dryer flooding problems did just
that and, additionally, lowered the costs of
generating steam. The cogeneration plant
crew gives thanks, as well as the board mill
production staff.
The dryer project targeted board
machine 3 (BM3), which produces liner-
board, coreboard, boxboard and specialty
grades from 39 to 100 lb./1000 sq.ft. (9
point to 28 point). It has a width of five
metres and runs at machine speeds rang-
ing from 110 to 193 m/min. The 6.7 MW
natural gas-fired cogeneration power plant
produces 115,000 lb./hr. of steam for the
board machine and the turbine.
Previous syphons had
short life span
Mill staff realized that something had to
be done to solve recurring and persistent
problems with dryer section syphon fail-
ures, condensate-flooded dryers and associ-
ated dryer bearing failures. Jean François
Désilets, production superintendent, says
that at most times before the project an
average of 10 dryers were locked out, the
majority of which were for broken syph-
ons. Some were shut for safety issues.
“We repaired 4 to 6 syphons on a main-
tenance shut, but we never got ahead of
the problem since the syphons had such
as short lifetime; it was hit and miss.” He
also notes that, during machine operation,
there could be a number of flooded dry-
ers but the operating crew had no way of
knowing since there were no sight glasses.
The need to operate at slower speeds on
heavy weight grades was another problem
caused by lower drying capacity.
Wilbur Wilton, chief operating engi-
neer, adds his description of the issues:
“We allocated two to three maintenance
people every shutdown to repair syph-
ons but the problem was getting worse.
We could repair five syphons but not 10
since we didn’t have enough manpower.
We were also repairing a lot of leaks at
the shutdown.” These leaks caused some
unsafe, slippery floors in the basement.
Since the condensate return was unreli-
able, the cogen plant across the road was
spending too much money for treating
and heating fresh makeup water from the
Trent river.
Premature dryer bearing failures were
another problem created by frequent dryer
flooding since the extra condensate load
added stress to the bearings. A dryer head
failure last year convinced the mill staff to
focus on the issue and make some decisive
corrective action. Moreover, over the long
run, the maintenance cost had to be cut
since too much effort was being put into
correcting chronic problems.
To rectify these urgent problems the mill
Syphon retrofit has
mill-wide benefits
A turnkey dryer project at Sonoco’s Trent Valley
mill eliminated previous syphon failures and
flooding, while reducing fresh water makeup
costs in the cogen plant.
By Mark Williamson, journalist engineer
Board machine #3.
Photo:MarkWilliamson
PPCNovDec2014.indd 16 14-11-05 1:03 PM

2. Case History
www.pulpandpapercanada.com November/December 2014 PULP & PAPER CANADA 17
Photo:Kadant
contracted Kadant Canada to conduct a machine study in Novem-
ber, 2012, that revealed an inherent weakness in 50 existing syph-
ons. These were very old, thin-wall bent pipe stationary syphons.
The remaining 10 dryers that form the dry-end high-pressure sec-
tion were equipped with Kadant HDRS rotary syphons. Kadant’s
proposal to replace the bent pipe stationary syphons with rotary
scoop syphons was accepted in June, 2013, and the installation
was completed in January, 2014, during a scheduled press rebuild
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shutdown. The project was more complex than usual since the
dryers had different journals and manhole placements. The new
products started up with no issues according to Désilets.
Designed for lower speed machines, rotary scoop syphons
efficiently remove condensate that pools at the bottom the dryer
shell. At lower speeds, the condensate pools rather than rimming
in an even layer around the circumference of the shell as con-
densate does at higher speeds. The scope of the turnkey project
Left: Flooding has been
eliminated as shown by
condensate flow sight glasses
on all dryers.
Middle: Jean-François Désilets.
Right: Wilbur Wilton.
Photos:MarkWilliamson
PPCNovDec2014.indd 17 14-11-05 1:03 PM

3. 18 PULP & PAPER CANADA November/December 2014 www.pulpandpapercanada.com
also included installing dual flow rotary joints, steam and con-
densate isolation ball valves, flex hoses and sight glasses that
show condensate flows from each dryer, as well as replacing
components in the thermocompressor to match its operating
curve to the new syphons. As an extra benefit, the move to com-
mon syphons and steam joints made the spare parts inventory
consistent for all dryers.
Raised the bar for maintenance
Since the startup, the syphons have been completely reliable
and the flooding problems have disappeared. The new sight
glasses are in place just in case there is a future problem. The
frequency of dryer bearing replacements has been reduced dra-
matically, from an average of once per month. There have been
no replacements since the installation of the scoop syphons.
Regular bearing temperature measurements show that the bear-
ings are running 15 to 20˚ F cooler than before. That should
extend their lifetime.
On the boardmaking side, Désilets sees that board quality
has been improved as papermakers can predictably set the top
and bottom dyers for effective board curl control. Before, the
crew did not know the extent or locations of flooded dryers.
Also, production speed can be maintained on heavy grades.
The reduction in maintenance burden has been a welcome
relief to Wilton since he can now plan preventive maintenance
more effectively rather than reacting to chronic problems. “We
have a more even distribution of time and manpower. Now, we
can plan and focus on priorities. This project has set a precedent
and raised the bar for our maintenance. By stabilizing the drying
and condensate return the rest of the steam system can now be
optimized,” he says.
Wilton says the cogen steam generation is more economical
since, with more condensate return, the fresh water makeup has
been reduced from 35% to 14%. This means less consumption
of pH-controlling amine and water softening chemicals for fresh
water and less energy to heat the river water from its sometimes
frigid level. Wilton estimates the consumption of expensive food
grade amines has been reduced by almost 80%.
Financial returns
The total numbers, as compiled by process engineer Cassandra
Bailey, tell the financial story. The maintenance and machine
downtime costs related to syphon failures, flooding and asso-
ciated bearing replacements have been eliminated up to July,
2014. This results in a saving of more than $12,000 per month.
The savings in amine for pH control is almost $11,000 year to
date in July and the water softening chemical saving for the same
period is $3,000. From May to July, 2014, the fresh water make-
up has been reduced by about 1,190 cu.m. /month to 1,1360,
amounting to a fuel cost saving of $4,000 to $5,500/month. The
cost of the study and the project was partially subsidized by
Union Gas, the local gas distributor. The mill has applied for a
gas consumption rebate under the Ontario EnerSmart program.
Mill manager Jason Giffen gives his final assessment of the
project results: “This was a big win for our mill. It has been a
game changer since we have been able to tackle and solve these
repetitive problems.” PPC
50 ANSET TOUJOURS VERT
Recycler pour recréer le monde,
Cascades s’engage à le faire
depuis 1964.
Chaque jour, ce sont près de 12 000 hommes
et femmes qui transforment votre milieu en
changeant la nature des choses.
Cela représente des centaines de produits
novateurs, allant du simple papier à de
complexes emballages, toujours faits dans
le respect des communautés et de
l’environnement.
Voilà pourquoi nous sommes fiers d’être l’un
des plus importants transformateurs de
matières recyclables au monde.
C’est dans notre nature.
Mario
Plourde
Président et
chef de la
direction
Alain
Lemaire
Cofondateur
Laurent
Lemaire
Cofondateur
Bernard
Lemaire
Cofondateur
PPCNovDec2014.indd 18 14-11-05 1:03 PM