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Transcript of PPI Awards 2011:
PPI Awards 2011: Honors well earned
w w w . r i s i . c o m - D e c e m b e r 2 0 1 1
By BRIAN DUFFY and BRAD BENZ
Nalco technology helped a linerboard mill improve strength and increase machine speed while reducing basis weight and steam use
ACHIEVING STRENGTH AND PRODUCTIVITY
In recent years, containerboard demand has been
rebounding in the worldwide economic recovery
and globalization of the market. Faster machine
speeds, increased operating rates, and the demand for
fiber to fulfill production capacity needs has been an
ongoing challenge to the industry. This demand has
caused fiber prices to escalate, especially recycled fiber
such as OCC from recovery processes. Many produc-
ers are implementing plans around fiber reduction
as it directly relates to manufacturing cost and selling
prices. Additionally, management teams are discussing
this every day in their plants. Having a well-managed
chemical program and a well-run mechanical opera-
tion is a highly important and effective way to sustain
the process of fiber reduction without compromising
strength such as ECT or compression strength.
Moving to lighter weights, strength, and energy
costs are critical drivers in the board and packaging
market. However, achieving the desired end-product
performance to satisfy demand while maintaining and
improving production efficiency can be a difficult task.
THE “L IGHT-WEIGHT ING” OF CONTAINERBOARD
The shift to lighter basis weights for containerboard
has been a compelling industry trend for the last
20 years. Since the adoption of Alternate Rule 41 in
1990, many users have opted for box compression
standards as the preferred method for specifying their
boxes. Several factors have significantly influenced
this shift, including advances in manufacturing tech-
nology, shifts in fiber supply, supply chain consider-
ations and sustainability awareness. Over time, basis
weights have also been steadily declining for key
linerboard grades, as illustrated in Table 1.
Achieving strength and reduced basis weight
targets can be a challenge for any papermaker,
especially when lower quality fibers are part of
the furnish mix. Use of Nalco’s patented METRIX®
technology program allows paperboard manufactur-
ers to increase strength, lower basis weight, enhance
production and improve sheet quality.
Variability in quality and supply of raw materials
also presents significant challenges to paperboard
manufacturers. Increasing refining to achieve
strength often leads to reduced drainage, lower
retention and higher energy costs. Increasing starch
dosages may also be ineffective as fibers become
saturated and additional starch cannot be retained.
Overuse of other cationic additives such as alum
and coagulants may also cause the furnish to become
cationically dispersed, affecting retention, sizing, system
Pulp & Paper International (PPI) D e c e m b e r 2 0 1 1
Table 1 - BASIS WEIGHTS FOR KEY LINERBOARD GRADES (SOURCE: RISI INTERNATIONAL, 2007)
foam, and finished product quality. Nalco developed
the multi-component METRIX retention, drainage, and
pressability program to allow board manufacturers to
simultaneously optimize basis weight, strength, caliper
and sheet smoothness. For example, the METRIX tech-
nology program provides papermakers with the flexibil-
ity to increase strength, while at the same time reducing
basis weight, increasing machine speed, improving
sheet properties and lowering fiber and energy costs.
Over the past 10 years, Nalco has committed signifi-
cant time and research investment into the continued
development of METRIX technology. Currently, the 7th
generation of this technology is being marketed, and
the 8th generation will be available globally in late 2012.
CASE STUDY EXAMPLE
Mill OverviewGrade: Linerboard
Basis weight produced: 35 and 42#/1000ft2 (170 and
205 g/m2)
Machine type: Single ply fourdrinier
Press type: 1st Straight through, 2nd LNP
Production rate: 45 tons/hr
Machine speed: 1,700-2,250 ft/min (518-686 m/min)
Furnish: 65% OCC and 35% kraft
Wet-end chemistry: CAT PAM flocculant, thin & thick
stock starch, rosin size & alum
pH: Acid
A linerboard manufacturer capable of produc-
ing 1,200 tons/day (1,091 tonnes/day) realized
serial reductions in production. Most days averaged
1,030 tons (938 tonnes) which was due to a need for
higher basis weight to meet quality specifications.
Low production was most prevalent on 35# (170 g/
m2) high performance linerboard and 42# (205 g/m2)
linerboard. This integrated board mill was using a
higher percentage of recycle fiber in comparison with
unbleached kraft pulp, 65% and 35% respectively. Re-
cycled fiber quality had also suffered over the years.
The thick stock Canadian standard freeness of
recycled fiber had declined by 100 mL or greater from
the facility’s recycle plant. Lower freeness was making it
increasingly difficult to achieve sheet quality parameters
at nominal basis weight and target speed/produc-
D e c e m b e r 2 0 1 1 Pulp & Paper International (PPI)
chemicals
Fig. 1 - METRIX TECHNOLOGY RESULTS – 35# HIGH PERFORMANCE LINERBOARD
Pulp & Paper International (PPI) D e c e m b e r 2 0 1 1
tion. On occasion, the paper machine in question was
running at target speed, but rarely longer than one day.
Several mechanical changes (refining, fourdrinier set-
up, pressing, drying) contributed to minimal improve-
ments in strength and speed. In addition, several wet
end chemical trials (coagulant, flocculant, starch, silica,
strength resin) achieved minimal to moderate benefit
in quality parameters. To meet quality goals, the mill
was forced to run 2-3 lb (0.9-1.4 kg) over standard basis
weight on select grades for this paper machine. This
manufacturer sold finished board on a manufactured
square foot/meter basis. Therefore, running over target
created several drawbacks which included increased
fiber cost, slower machine speed, decreased produc-
tion rates, and higher energy and unit cost per ton of
linerboard produced.
The manufacturer wanted to run the machine
at nominal basis weight or below while maintaining
strength targets in ring crush and mullen. In addition,
other key business drivers were increased production
rates and reduced operating costs. Nalco understood
that meeting these goals could prove difficult given the
present and past operating conditions on the paper
machine and that minimal impacts had been realized
with previous changes.
Nalco’s Industry Technical Consultants in coop-
eration with its on-site team performed a thorough
mechanical, operational and chemical (MOC) audit.
The team provided several recommendations in each
area with a major focus on chemistry. From a chemis-
try standpoint, there was a need to address drainage
on the fourdrinier without disrupting sheet forma-
tion. This particular machine has a very long forming
section. The wet end chemistry and their injection
point was not overly complex with the use of alum,
starch, rosin size and cationic flocculant.
A review of audit findings was communicated
to the manufacturer and a plan was proposed to
improve machine speed and increase strength.
Chemical recommendations were made to limit early
fourdrinier drainage, focusing on vacuum drainage
and pressing, as well as strength development.
PROGRAM DES IGN
As a first step, a high molecular weight cationic floc-
chemicals
Fig. 2 - METRIX TECHNOLOGY RESULTS – 42# LINERBOARD
culant along with colloidal silica and a balance of thin
versus thick stock starch provided necessary drainage
on the fourdrinier. The ability to move the dry line on
the fourdrinier was evident.
However, this particular chemical program did
not result in increased machine speed or strength.
Several parameters were adjusted on the fourdrinier
and press section to take advantage of the drainage,
but no adjustment provided sustained results. This
was not a major setback as pre-trial audit findings
suggested this was possibly due to water handling
in the press section. The initial chemical program
provided important technical information and
demonstrated that the Nalco team had the ability to
understand the papermaking process dynamics and
provide a technical reason for the paper machine
response observed as well as propose a solution.
The next step focused on a two-component poly-
mer approach using a high molecular weight cationic
flocculant in combination with a METRIX technol-
ogy product. The technology was selected for this
customer due to proven effectiveness with similar
furnishes and also due to the inability of a traditional
retention and drainage program to meet the mill’s key
business drivers.
In addition, METRIX technology provides addi-
tional strength to allow for reduction in basis weight
and refining. Experience with the technology, along
with a thorough understanding of the papermaking
process at this manufacturer’s facility, allowed Nalco
to design a program that would provide maximum
environmental and financial savings at the lowest
sustainable cost. This program integration provides
the customer an Environmental Return on Invest-
ment (eROI), delivering both environmental perfor-
mance and financial payback.
In designing the feed strategy of step two, existing
wet end additives were considered as well as their
respective location to each unit operation. A feed
location was selected that provided maximum reten-
tion with minimal interference from disruptive fines
and colloidal material. The strategy incorporated a
co-mix approach with high molecular weight cationic
flocculant and METRIX technology. At this facility an
overfeed situation occurred at 3.0 lb/ton (1.36 kg/ton)
of METRIX technology; therefore, the team selected
2.0 lb/ton (0.91 kg/ton) as the final dosage.
PROGRAM RESULTS
Analysis was completed on 35# and 42# grades,
running the paper machine at maximum steam
consumption/speed optimization.
• 4-5%basisweightreduction
• 7-10%manufacturedsquarefootageincrease
• 7-10%reelspeedincrease
• 1.5-2tonperhourproductionincrease
• 6%reductioninrefiningenergyperunittonon42#
(205 g/m2), no change on 35# (170 g/m2)
• Maintainedtargetringcrushandmullen
• OptimumMETRIXtechnologydosage–2to2.5lb/
ton (0.91 to 1.13 kg/ton)
• Minimaldosagechangesforexistingwetend
chemistry
• CustomerROI:$750/operatinghour
• Saved 90,000 gallons/yr in flocculant makedown water
The METRIX Technology response prior to a
speed and basis weight change showed a 14% reduc-
tion in steam consumption and a 10% increase in
both ring crush and mullen, grade dependent.
CONCLUS ION
METRIX technology is a synergistic, multi-compo-
nent program developed to enhance productivity,
press section dewatering and strength development
for paperboard manufacturers. It encompasses the
use of a reactive polymer and one of Nalco’s advanced
retention and drainage programs. Program benefits
are designed to include increased sheet strength and
machine speed from enhanced dewatering during
pressing and drying operations. PPI
Brian Duffy is Senior Industry Development Manager,
Board & Packaging Grades, and Brad Benz, Senior
Industry Technical Consultant, Nalco Company
Literature
1. The Future of Lightweight Containerboard in North
America, RISI International, 2007
2. Corrugated Today Magazine, July/August 2011
chemicals
To read more articles on Chemicals, visit our Chemicals Technology Channel at www.risi.com/technologychannels/chemicals
R e p r i n t e d w i t h p e r m i s s i o n f ro m P u l p & P a p e r I n t e r n a t i o n a l © D e c e m b e r 2 0 1 1
Nalco – Your partner for sustainable growth
Cost reduction is a key business driver for every papermaker.
Nalco solutions are specially designed to deliver cost improvement, while reducing environmental impact.
Water usage◆ System closure◆ Shower optimization◆ Additive dilution◆ Water management
Nalco’s key solutionsPARETO mixing technologyNAL-TEX® advanced cleaning 3D TRASAR® technology for cooling and boiler waterVELOX® press dewatering Integrated Water Management (IWM)
Energy savings◆ Felt performance◆ Press dewatering◆Boilerefficiency
Water reuseGRADE: uncoated fine paperAPPLICATION: PARETO ◆ increased production by
reducing wet-end breaks◆ reduced fresh water
usage: 105,000 m3/year ◆ estimated annual
savings: US$3,400,000
Steam savingsGRADE: coated fine paperAPPLICATION: VELOX◆ increased machine speed
from 1,150 to 1,200 m/min◆ estimated annual
savings: US$1,500,000
Water & energy savingsGRADE: boardAPPLICATION: 3D TRASAR technology◆ real-time monitoring
and control◆ reduced acid cleaning
frequency by 50%◆ eliminated unscheduled
shutdown◆ estimated annual savings:
US$30,000
Waste water recycleGRADE: gypsum linerAPPLICATION: Waste Water Treatment◆ improved end product quality
by eliminating chlorine ions from waste stream
◆ enabled 16,000 m3 per day of waste water to be recycled to papermaking process
Value delivered
Nalco is your partner in achieving your economic, environmental and social goals.Nalco Company1601 WestDiehlRoad•Naperville,Illinois60563-1198•USA•6303051000Latin America: Av.dasNaçõesUnidas17.891•6°Andar04795-100•SãoPaulo•SP•Brazil•551156446500Europe: A-One Business Center•Z.A.LaPièce1•Routedel’Etraz•1180-Rolle•Switzerland•41(0)216146400Asia Pacific: 2InternationalBusinessPark•#02-20TheStrategyTower2•Singapore609930•6565056868
www.nalco.com/paper
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