Customer case studies

About 90% of the production of coated paper at Oji Kasugai is supplied to the highly competitive and quality-conscious Japanese market, so the company cannot compromise on quality. It therefore needs long runs of uniform quality; with reduced LWC production costs as an extra benefit.

“Ceramic-tipped coating blades help us meet our marketing targets”

Nordland Papier, Dörpen, Germany is one of the largest, most modern, and competitive manufacturers of woodfree paper in Europe. A member of the UPM-Kymmene Group, Nordland produces about a million tonnes of fine papers every year.

During 1998 Nordland bought about 28,500 meters of Duroblade, the ceramic-tipped coating blade manufactured and marketed by BTG. “The acceptance of our products on the market leads us to believe we can be numbered among the best bulk producers of high-quality fine paper grades in Europe. Our target is to offer our market a wide range of grades of highly uniform quality, manufactured in highly efficient production processes. Ceramic-tipped coating blades have contributed to our consistently achieving this goal,” says Mr. Werner Baumeister, the Production Manager at the mill.

At a time when Chinese coated board producers need to rasise productivity, enchance quality and minimize costs at the same time, BTG's experience and solutions are an efficient way to stabilize and optimize not only the blade coating process but the whole coated board production.

The most common leveling elements for coating of paperboard, namely smooth rods and steel blades (running in bent mode), are compared in this study to soft-tipped DUROBLADE and systematically evaluated in different combinations for pre-coat and topcoat operations.

Uniform fiber coverage requires contour coating, while low surface roughness demands a leveling coating process, a situation that forces paperboard producers to compromise between these two typical characteristics of premium-coated paperboard.

ABC and Duroblade® technology bolsters niche product market position at Fraser Madawaska.

"The benefits of ceramic-tipped blades make the price we pay for them worth it"

Introduction

In spite of increased use of DUROBLADE in the creping industry worldwide, there are still some tissue producers who are unwilling to try ceramic-tipped blades on their machines because of what they fear are potential risks of Yankee damage.

BTG's Creping Blade Control permits adjusting the creping pocket angle and the linear blade load while running, offering greater control over the creping process than any other creping blade holder.

Although good marketing has improved overall profitability at Ortmann, utilization of top-of-the-line technology has also contributed to greater profitability by helping to ensure consistent product quality and efficient operation.

Those who are familiar with creping appreciate the high temperature reached at the blade tip and its possible deleterious effects.

A number of factors stand between tissue-makers and their goal to meet the current requirements for tissue quality.

Polyelectrolyte titration using PCD-03 and PCD-T3 is a good way to determine the content of colloidally dissolved substances.

Yeast cultivation needs to be optimized and defective yeast screened. Polyelectrolyte titration using PCD-03 and PCD-T3 helps in effective yeast production.

Polyelectrolyte titration using PCD-03 pH and PCD-T3 is a very good means of studying and optimizing the dosage of PAC.

With increasing degrees of substitution of the cationic starch molecules, the consumption of titrant increases.

Using GAS-60 helps stabilize process, increases productivity and delivers lower chemical deaerator dosage.

Using GAS-60 to reduce pinholes, deliver fewer cleaning stops at the coater and generate significant cost savings.

Using GAS-60 and deaerator control to reduce pinholes in newsprint; return on investment in just four months.

Reduced consumption and chemical savings by using charge analysis and filtration sampling.

Using charge analysis and stock sampling to increase strength, reduce deposits, improve starch adsorption and reduce downtime.

Using charge detection to reduce WSR dosage and foam and improve wet strength - with a return on investment in just four months.

Using inline retention control to reduce variations in retention aid dosage, stabilize drainage, increase production and raise profits.

Using inline retention control to decrease retention aid dosage, increase machine runnability, and deliver a more uniform basis weight in machine direction and a cleaner PM circuit.

Using inline retention control to stabilize white water and headbox consistencies, improve filter retention and bring down production costs.

Using inline retention control and drainage analysis to stabilize white water consistency and drainage, achieve higher machine speeds and increases in both production levels and profits.

Using charge control in tissue to reduce depositsweb breaks and COD, and improve wet strength.

With the PCD-03 Particle Charge Detector combined with the PCD-T3 you can measure the concentration of anionic trash and track and locate sources of charges within the papermaking process. This data helps paper mills introduce preventive check-ups and avoid expensive downtime.

Using SZP-04 or SZP-06 elecrtodes to analyze alkaline aluminium oxide dispersion and measure the influence of pH.

Using the SZP-04 or SZP-06 electordes to analyze calcium carbonate in slurry and measure the influence of dilution.

Using the SZP-04 or SZP-06 electrodes to analyse calcined kaolin and measure the influence of conductivity.

Using the SZP-04 or SZP-06 electrodes to reverse the charge of a kaolin slurry by adding polyvinylamine.

The new refiners are positioned in a series, one coarse and the other for trim refining and the DRT measures the freeness of the gum pulp between them and the blend chest.

An easy choice

This move allowed monitoring this process on-line from fresh measurements every six minutes. The instrument functions as a watchdog for operators, helping them to regulate chemical dosages in the softwood TCF bleach plant. The bleaching chemicals are peroxide and ozone.

The pulp is used in production of board, tissue, fluff and printing and writing grades, and it is hydrogen peroxide bleached to brightnesses ranging between 60 and 80% ISO.
About 25% of production is bleached in the 75 to 80% ISO range, and some time ago the mill discovered that something in the bleaching process was causing peroxide dosages to drop
below the required levels to bleach in this range.

Two-ply, white-top linerboard ranging in basis weight from 115 to 250 g/m 2 is produced on PM 2. Operators use information from the DRTs to monitor freeness in a standard specific energy application.

The Lessebo Mill in Lessebo, Sweden, is one of two mills in the Klippan AB Group. Paper was first produced at the mill in 1693, and as early as in the beginning of the past century the mill had become Scandinavias first integrated paper mill.

According to staff, the major benefits of real-time kappa measurement at the white sack and kraft paper mill are two.

Twenty-four months of operation, including an intensive testing period, have shown that the mill has optimized the effects of hydrogen peroxide by minimizing catalase activity.

Until the late 1940s when Kaga Paper pioneered the use of recycled paper, the raw material for production at the mill was rice straw. Today its roughly 99% recycled paper. The mill produces board in as many as 10 layers varying in
basis weights from 270 to 1000 g/m2. All of the layers except the top layer are produced from mixed non-deinked and non-bleached wastepaper.

Flax is a strong and very flexible fiber and aids in formation on the paper machines," says
automatic instrumentation department director Shenwu Jia.

Broke the major source of charge variation

1 Process monitoring

At the La Riba tissue mill observing this policy has meant closing down household paper operations and focusing full attention on toilet paper production. Paying close attention to minimizing production costs and maximizing quality has been a continuous process at the mill for more than 25 years. One of our steps in this direction was the investment in a refining analyzer, says Arcadi Llad, the Mill Manager. Since then, we have
experienced reduced energy consumption and thereby reduced costs of  production as well as improved product quality.

The overall benefits of the concept are optimized efficiency, improved chemical dosing, increased production and uniform product quality, all factors that lead to better profitability.

Figure 1 is a simplified illustration of the DIP 2 line. It shows the positioning of the TCT-2302 Total Consistency Transmitter at the outlet of the line just before the disk filter. The screw press positioned after the disk filter is the last possible place in the DIP line where ash content can be adjusted before the paper machine.

Its not unusual for us to change grades four times during one working day, changes can involve going from low to high basis weights and from light to dark colors or vice versa," says ngel Largo, the Mill Manager.

Running at full speed will have to wait until the machine and all the processes around it are optimized, says Lennart Karlsson, the Process Engineer for Mechanical Pulp Production.

Mr. Karlssons area of specialty is TMP production, and he points out that before starting up PM 11, the capacity of the TMP 3 plant had to be increased from 700 to 900 tpd. This involved replacing two primary refiners and converting two refining lines to new technology that reduced coarseness and increased smoothness while reducing energy consumption. Other work in the TMP 3 plant included modernizing screening and upgrading the chip dewatering, refiner feeding and rejects refining systems.

Enabling customers to emulate actual production circumstances is the aim of the operation. The plant is equipped with all of the machinery and systems marketed by Cellwood Machinery. All machinery is full-scale and can be easily arranged to an optimum system to suit customer requirements.

Kimberly-Clark Koblenz, Germany
The Kimberly-Clark Koblenz mill is a subsidiary of Kimberly-Clark, USA. The mill produces and converts about 40,000 tpy of what it calls Away From Home (AFH) tissue, or in other words, tissues used in commercial operations. The raw material is a variety of high-quality wastepaper. The mill has three TCT-2300s in operation in three different applications: one in sludge treatment, and two in the deinking line. The job of the TCT in sludge treatment is to regulate flocculation agent dosages before a drum filter. The target is use no more of the agent than is actually required to ensure sludge of a specified dry solids content at the end of the dewatering process. See Figure 1.

Our method for determining dosages actually was to take some sludge in our hands after it passed over a dewatering screen, feel it for a while to guess its consistency and then adjust the flocculation dosages according to our manual estimations. Most often we overdosed to be on the safe side.
Since the TCT, which operates in a slurry ranging from 1.0 to 3.0% consistency, the dosages are in a control loop. This saves us a lot of money each month and provides us with sludge at the dry solids content we want, says Mr. Scherwa.

Constant consistency before flotation
One of the TCTs in the deinking line is positioned after the mixing pump to the flotation cell. The TCT functions to guarantee constant consistency before the flotation cell and the pump guarantees constant flow. Consistency before the pump is about 2.0%. After the mixing pump it ranges from 1.1 to 1.3%. Our target in this application is quality, and we get the best results when the flotation cell operates at constant flow and consistency. The TCT has enabled us to optimize the operation of the flotation cell. We tried an automatic optical bypass system but it required a lot of maintenance and the availability of extra equipment for fresh water and air pressure to operate, says Mr. Scherwa.

and before the slot sorter
The other TCT in the deinking line is positioned before the slot sorter and after a mixing pump. It functions as a cascade control providing the setpoint for the pulp flow controller. The TCT ensures that consistency into the slot sorter ranges from 0.7 to 0.8%. If the consistency into the slot sorter is higher than 0.7 to 0.8%, the sorter plugs. Plugging damages the slot basket, which is very expensive to replace. Before the TCT, the sorter plugged three or four times a month. Now it doesnt plug. This improvement has resulted in better product quality, but greater productivity is our major gain, says Mr. Scherwa.

Haindl Walsum, Germany
The Haindl Duisburg-Walsum mill produces double-sided coated printing papers in reels for offset and gravure on two paper machines from TMP, kraft pulp and recycled wastepaper. Annual production is 420,000 tons.
There are five TCT-2300s in operation at the mill. They are positioned at the inlets to the high-pressure screens, three before each main screen and two before each reject screen. They are in a consistency control loop to ensure that the screens operate efficiently. According to Gerd Zapusek, Instrumentation Manager at the mill, consistency at this point in the process
ranges from 0.8 to 1.5%. The screens are sensitive to varying levels of consistency and they plug easily at a consistency that is too high.
With the screens optimized, they run at three times 180 tpd per screen. Running at this rate, we can meet the production targets for our paper machines. The TCTs help us get this job done, says Mr. Zapusek.
Previous to the TCTs, Haindl used static blade transmitters in these sampling positions. They didnt work,  says Mr. Zapusek. They werent accurate and didnt produce repeatable results. They caused two or three
stoppages each day for recalibration. The TCTs have eliminated these problems. We take lab samples once each shift to check calibration and
weve seen virtually no drift since they were installed. Now the difference between inlet and outlet consistency is constant and comparable. Before the TCTs it was not, says Mr. Zapusek.

Bowater Thunder Bay, Canada
The Bowater Thunder Bay mill is a member of the Bowater Newsprint Division, which has mills strategically located to serve customers in the United States, Canada, Europe, Asia, Latin America and the Middle East.
Newsprint capacity at Thunder Bay is about 515,000 tpy produced on three twin-wire machines from TMP, groundwood and recycled old newspapers and magazines. Controlling dilution before the acid disk filter.
The TCT-2300 at Bowater measures total consistency in the feed to the acid disk filter on the deinking line. Consistency in this application varies from 0.5 to 1.0%. The instruments task is to control the mix of water and acid added before the disk filter. The instrument has been in operation for about nine months. It was originally calibrated with six sample points at the time of start-up. Weve conducted regular calibration checks and since they have fallen on the calibration curve, we have had no need for adjustment. Essentially we have seen no drift during the nine months. And the instrument has been available the whole time, says Chris Pembroke, Technical Assistant on PM 5. Stable consistency in the acid disk filter affects the stability of succeeding processes. Uniform consistency into the saveall and the twinwire press it feeds helps prevent process upsets. Greater control over all processes to gain smoother and more efficient overall operations is what every papermaker strives for. The TCT has helped us take a step further in this direction, says Mr. Pembroke.

"One of the greatest benefits of accurate consistency measurement in feed forward control is product of uniform basis weight. Whats more, with a well-functioning feed forward control loop, we can start producing onspec product quickly after stoppages.

The challenge to high-quality

Brightness and residual chemical transmitters

Rhein Papier GmbH is an Alliance Partner with MD Lang. The mill is designed to produce 280,000 tpy of 45 g/m 2 news-print at a machine speed of 1800 m/min. Construction began in July 2001, and exactly one year later it was running at the record start-up speed of 1560 m/min. Hopes for 2003 are to produce 250,000 tons according to the start-up curve. The major portion of the mills production is supplied to the domestic market.

"So far they have served us well," says Mr. Maischberger, adding "Weve had them in service around here for some 30 years, and our experience of them is good. "Their repeatability is good and the Smart system with the hand-held terminal enables us to calibrate and set not only the MEK 2300 transmitters, but also a number of other BTG instruments in a easy and informative way. Any new transmitters we install always feature the Smart system," says Mr. Maischberger. The transmitters are subject to regular maintenance routines, a factor that contributes to their reliable operation.

The Daishowa mill in Quebec City, Quebec, Canada produces newsprint
and directory grades from unbleached TMP and deinked secondary fibers.

The supplier uses the CAT during weekly inspections of the catalase situation in the plant, the aim being to establish an accurate reading of the amount of chemicals required to keep catalase under control.

CAT accurately and reliably measures, analyzes and monitors catalase activity as well as the residual hydrogen peroxide content in process water at any given time.

The CAT-5000 stabilizes residual peroxide levels, and this allows optimizing pulping, improving deinking in the flotation cell and increasing the possibility of predicting final brightness.

Different types of bacteria produce catalase, and they thrive in DIP processes where they find good growth conditions such as in closed white-water loops, tanks and towers.

Other sources of catalase activity are old and/or wet wastepaper and the wastewater used in mills to decrease specific water consumption.

Shotton

THE CARTIERE BURGO MILL IN MANTOVA, ITALY