Fine Paper Producer Achieves Maximum Economic Benefits with POSITEK™ 3G Microparticle Technology8400 mm BTU/year savings

CH-966

CASE STUDY – PAPER

AIR

ENERGY

EARTH

Mill OverviewGrade: Alkaline Uncoated Free Sheet Text and Cover

Basis Weight Produced: 60# to 200#/3300ft2

Machine Type: wo Single Ply Fourdrinier Paper Machines

Production Rate: 200 TPD

Machine Speed: 900 – 1800 FPM

Furnish: 38% Recycle, 36% Bleached Kraft, 26% Ash

Wet-end Chemistry: Anionic Flocculant, PAC, Thin and Thick Stock Starch, ASA

pH: 7.1

Reduced steam used to dry sheet by 13 percent as main section steam was reduced on average from 60 psi down to 52 psi. This equates to a reduction of 1000 lb/hr of steam.

8400 mm BTU/year savings

With $7.25/1,000,000 BTUs, the annual savings is $60,900 /yr.

Sheet ash was elevated to 28 percent from 25 percent, reducing the need for virgin fiber by 3 percent. Also improved drainage allowed for higher levels of post consumer recycled fiber.

Additional savings of 393 tons of fiber per year

Reduce 12 trucks per year, equiva-lent to 16,560 lb/year

At $850/ton for fiber costs, sav-ings of $334,688/yr on heavy-weight grades which account for approximately 25 percent of their grade breakdown.

CO2 prices varies with marketplace

Customer ImpaCt eConomIC resultseROISM

eROI is our exponential value: the combined outcomes of improved performance, operational efficiency and sustainable impact delivered through our services and programs.

OVERVIEW

Today’s fine paper producers face uncertain market conditions every day. Thus, cost control becomes a primary focus. Working with the right retention, drainage and formation supplier, papermakers can reduce major cost categories and ultimately improve their bottom line.

POSITEK 3G technology is the latest generation in Nalco microparticle program technology. The program is designed to promote drainage and retention without causing any negative effects caused by over-flocculation.

POSITEK 3G technology allows papermakers to use less fiber and more filler, for lower cost and higher quality paper. It does not take long to realize mill profits can increase significantly if fillers like calcium carbonate, clays, and titanium dioxide can be substituted for more expensive fiber. However, in order to realize savings, these fillers must be retained in the sheet. The extent to which the filler is retained determines the economic payback to the mill and impacts paper machine runnability.

A retention, drainage, and formation program must provide excellent first pass fiber and filler retention. Low filler retention will adversely impact the deposition potential of the entire papermaking system and can lead to breaks and holes.

The mill was very familiar with the benefits of using a high performance retention, drainage, and formation program since it had been utilizing one from the mid 1980’s. Two earlier generations of Nalco microparticle technology had been in use continuously at the mill since that time.

In recent years, the mill had achieved desirable results using a specialty blend of poly aluminum chloride as the coagulant, a high molecular weight anionic polymer as the flocculant, and a second generation colloidal silica as the microparticle. All three of these chemistries were provided by Nalco.

Throughout the learning curve since conversion, Nalco and the papermaker had made significant strides in the retention program to allow for higher ash levels and increased machine speeds. The retention, drainage, and formation program had been optimized to achieve sheet ash of 18-25 percent.

The mill had desired to further improve the cost performance of the retention, drainage, and formation program while increasing the ash content in the sheet above 25 percent. Upon the development and introduction of Nalco’s newest generation microparticle technology, POSITEK 3G 8699 technology was brought to this mill for trial and evaluation.

POSITEK 3G 8699 technology is a colloidal silica dispersion that is specifically structured to enhance drainage in a controllable manner and increase the retention of filler and fiber fines. This small, highly charged particle augments the existing retention mechanisms of coagulation and flocculation. Due to the small size of colloidal silica, microflocs are formed as the silica bonds with cationic sources that are adsorbed onto the surface of fibers, fines and fillers. Smaller flocs are formed which, in turn, leads to better distribution throughout the sheet.

BUSINESS SITUATION

A North American paper mill converted to alkaline papermaking in the early 1980’s. This producer of premium writing, text, cover, and digital papers offered some of the highest quality and well known brands available in the industry today.

Furnish components consisted of purchased pulp including post consumer recycle, precipitated calcium carbonate, some clay, wet end starch and ASA as the sizing agent. Throughout the years since converting to alkaline, many retention programs were evaluated in an effort to maximize the amount of sheet ash. Their goal was to substitute filler for fiber at a 4:1 payback.

 

Table  1:    POSITEK  3G  8699  technology  Impact  on  paper  Machine  Drying    

 

eROI    

 

Environmental:  Reduced  steam  used  to  dry  sheet  by  13  percent  as  main  section  steam  was  reduced  on  average  from  60  psi  down  to  52  psi.    This  equates  to  a  reduction  of  1000  lb/hr  of  steam.      

8400 mmBTU/year savings  

Financial:  With  $7.25/1,000,000  BTUs,  the  annual  savings  is  $60,900  /yr.  

 Environmental:  Sheet  ash  was  elevated  to  28  percent  from  25  percent,  reducing  the  need  for  virgin  fiber  by  3  percent.  Also  improved  drainage  allowed  for  higher  levels  of  post  consumer  recycled  fiber.      

50 52 54 56 58 60 62

0

1

2

3

4

5

9:50 10:20 11:00 11:45 12:10 1:10 2:05 M

/S S

team

(psi

)

Silic

a D

osag

e (lb

s/to

n)

Silica Dosage

8699 Trial: Silica Dosage vs M/S Steam

Silica Dosage M/S Steam

Transition to POSITEK 3G

Figure 1 – POSITEK 3G 8699 technology Impact on paper Machine Drying.

PROGRAM RESULTS

Over the course of several weeks, a series of trials were run to compare the performance of POSITEK 3G 8699 technology with that of the second generation microparticle program from Nalco. When the trials were completed on text and cover grades ranging from 60 lb to 146 lb basis weights, it was clear the new microparticle was the program of choice for this mill.

Optimal results were achieved at dosages ranging from 20 to 45 percent less per ton of paper produced when comparing the POSITEK 3G 8699 technology to the existing colloidal silica microparticle. Additional results achieved include:

• Firstpassashretentionimproved7points from 63 to 70 percent

• Formationimproved2-4pointsandvisibly the sheet looked better

• Tabledrainageimproved,maintained wet line while increasing fan pump by 25 rpms

• LowVacwasdecreasedfrom45/45to 15/20

• Abilitytoaddanadditional 260 gpm of water into headbox

• Dryingwasimproved,main section steam dropped from 60 to 52 psi (Figure I)

• Onaverage,retentionprogramcosts reduced by 15%

CONCLUSION

Today, this mill has integrated the POSITEK 3G technology program fully into its wet end chemistry as its retention, drainage, and formation program. Not only did the economics prove successful, but better physical and optical properties have also been realized. Elevated sheet ash levels have been achieved to as high as 28 percent.

With intense focus on cost optimization, Nalco technologies can help reduce variable cost and increase machine efficiency while reducing the use of raw materials, water, energy, and commodity chemicals.

POSITEK 3G, Ecolab, eROI, NALCO and the logos are Trademarks of Ecolab USA Inc.©2010, 2014 Ecolab USA Inc. All Rights Reserved 10-14

Nalco, an Ecolab CompanyNorth America: Headquarters – 1601 West Diehl Road • Naperville, Illinois 60563 • USA Nalco Champion – 7705 Highway 90-A • Sugar Land, Texas 77478 • USAEurope: Richtistrasse 7 • 8304 Wallisellen • SwitzerlandAsia Pacific: 2 International Business Park • #02-20 The Strategy Tower 2 • Singapore 609930Latin America: Av. das Nações Unidas 17.891 • 6° andar • São Paulo • SP • Brazil • CEP 04795-100

www.nalco.com