· 2017. 8. 16. · 03/09 x perspectives of biorefinery concepts in the paper industry x ozone and...

www.ptspaper.de

03/09

Perspectives of biorefinery concepts in the Xpaper industryOzone and membrane filtration – Which me- Xthod ranks first today?Strength gains without pulp refining XCo-operation with PAMA: Calender design Xbased on pre-trials in the PTS pilot plant

Increasing the amount of filler in copy paper Xand SC paperKlingele mill reduces energy cost by means of Xthe SystemCheck EnergyRapid analysis of paper components XDynamic differential scanning calorimetry Ximproves fibre and paper analyses

M a g a z i n e f o r t h e P a P e r i n d u s t r y

2 PTS NewS 03/2009 Inhalt

Research

PTS at the AiF Innovation Day 2009 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Forum “Modelling and prediction of fibre-based product properties“ . . . . . . . . . . . . . . . .3

EU project SUNPAP startet this summer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Metallic sinterable papers – a flexible semi-finished product for powder metallurgy . . . 4

Perspectives of biorefinery concepts in the paper industry . . . . . . . . . . . . . . . . . . . . . . . . 6

10 years of advanced waste water treatment by ozone and membrane filtration – Which method ranks first today? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7

Monitoring the quality and composition of recovered paper by means of NIR measuring technology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

Strength gains without pulp refining . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

New light cast on specialty papers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

Customer Projects

Calender design based on pre-trials in the PTS pilot plant . . . . . . . . . . . . . . . . . . . . . . . .14

Using chemically activated fillers to increase the amount of filler in copy paper and SC paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

Klingele mill reduces energy cost by means of the SystemCheck Energy® . . . . . . . . . . . 22

PTS “Virtual Fractionation” SoftSensor successfully installed at Norske Skog . . . . . . . 24

Technology transfer funding in small and medium sized enterprises in Saxony . . . . . . .25

Measuring

Rapid analysis of paper components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

Consistent further development of DOMAS: Version 3 .0 available in December . . . . . . .27

Dynamic differential scanning calorimetry improves fibre and paper analyses . . . . . . 28

PTS know-how lends support to complaint management . . . . . . . . . . . . . . . . . . . . . . . . 29

Case study: Formation measurement using a Procemex camera . . . . . . . . . . . . . . . . . . . 30

Training

14th PTS CTP Deinking Symposium in Leipzig . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

International Scientific Symposium on Applied Interface Chemistry . . . . . . . . . . . . . . . .31

Publisher Papiertechnische Stiftung (PTS)

Heßstr . 134, 80797 München

Editor/Layout Erwin Polmann

Mail: erwin .polmann@ptspaper .de

Translation Corina Schmidt

Briant McEwen

IMPRINT

Front picture: PAMA Papiermaschinen GmbH

3PTS NewS 03/2009 ReseaRch

More than 1000 visitors visited the Berlin office of AiF on 1st July 2009 to find out more about innovative ideas pre-sented by small and medium-sized enterprises.

For the 16th consecutive time, a total of more than 200 firms and research institutions from all parts of Germany presented within this framework new products, processes and services that were developed with the financial support for technology promotion provided by the Federal Ministry of Economics and Technology (BMWi).PTS presented initial results of its research project entitled “Novel product protection based on antigen-antibody reac-tions on paper”. Product counterfeitung and piracy have become a serious economic problem in nearly all markets. The economic damage caused in Germany alone amounts to as much as €142bn and as many as 70,000 jobs are po-tentially endangered. The International Chamber of Com-merce reckons that the damage to brand manufacturers as a result of piracy and counterfeiting is in the range of $600bn worldwide.In a new research project, PTS is developing new product safety features based on the underlying principles of im-munoassays: antigen and antibody form a complex based on the induced-fit concept which in turn elicits a colour reaction. The antigen will be applied onto the paper surface using the sol-gel technique. It will be held in the pores of the sol-gel matrix without covalent bonds, thus making it available for reactions and interactions.

Objectives of the project:Development of a printing ink as a safety feature against •counterfeiting.Use of sol-gel materials in which bio molecules are im-•mobilized.Use of bio molecules which can be identified by an im-•munoassay, e.g. ELISA test, as a result of their reactions with specific antibodies (induced-fit concept).

AdvantagesImmunoassay-based analysis is very easy to perform, •fast and highly specific. Solving the code of bio molecules is very difficult as pro-•tein analyses are still very expensive and complex. As the safety feature will be transparent, it can be ap-•plied on top of existing features.

The visitors showed great interest in the new product pro-tection technology. Among other things, the possibility of transferring this technology to other sectors e.g. car indus-try (spare parts) was discussed, making follow-up projects on other substrate classes possible.

PTS AT THE AIF INNOVATION DAy 2009

Sabine Hottmann 0049 3529 551 663 [email protected]

contact

The results of the two work groups and possible overlaps will be discussed in joint sessions. The state of the art and pertinent research demands will be discussed in order to generate concrete projects.The organisers hope for an active response from colleagues dealing with modelling and simulation in the fields of pa-per, paperboard, wood and (composite) fibres. The forum is to enable the exchange of views especially among the representatives of research institutions.

Representatives of the industry and of leading research in-stitutions will meet for their 3rd research forum on “Model-ling and prediction of fibre-based product properties” at PTS Heidenau on 23 November 2009, one day before the PTS Pulp Symposium.

At their previous two meetings, the participants took stock and defined the contents of the forum. They introduced themselves with their key research areas, confirming their willingness to co-operate in joint projects. After discuss-ing the research demands and the forum’s main goals, the majority of attendees agreed on the following two subject areas:

surface properties of paper and •mastering the scale-up from micrometer range to end •product.

These tasks will be performed by two work groups, focus-ing on selected properties on micro, meso and macro levels.

FORUM “MODELLINg AND PREDICTION OF FIBRE-BASED PRODUCT PROPERTIES“

Sven Altmann 0049 3529 551 634 [email protected]

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4 PTS NewS 03/2009 ReseaRch

Tiemo Arndt 0049 3529 551 643 [email protected]

Dr. Josef Eckl 0049 89 12146 274 [email protected]

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EU PROjECT SUNPAP STARTET THIS SUMMER

The European SUNPAP (Scaling Up Nanopar-ticles in Modern Paper Making) project with a budget of EUR 9.8 million aims to demonstrate that it is possible to manufacture high-quality functional paper and packaging products on a pilot scale by using flexible, energy-efficient and environmentally friendly processes.

Nanocellulose is being researched globally, primarily at the laboratory scale. With the SUNPAP Project, the intention is to take research to the next level – to pilot scale and all the way through to the end product. The project will update the current proc-esses of paper manufacture and coat-ing and identify new product oppor-tunities through the use of functional fibre-based materials instead of synthetic petroleum-based materials. The ben-efits include independence from oil prices, lighter products and the creation of new functionalities and applications in the future. The new coating techniques will allow material-efficient, thin layers to be spread across the paper surface.

The project aims to promote the competitiveness of the for-est industry and create new products and markets. This will benefit paper manufacturers and the packaging industry, as well as the consumers of fibre-based products.

Launched this summer with 22 partners, the three-year SUNPAP Project will run until June 2012. The EU will cover nearly 70% of the project costs. Most of the project work

will be carried out in Finland, Germany and France at research centres committed to the re-generation of forest industries (KCL/VTT, PTS and CTP).

The Finnish partners include the project coor-dinator KCL, Helsinki University of Technology, Tampere University of Technology, Pöyry, The Finnish Insti-tute of Occupational Health, and Bi-osafe. Other research partners come from Italy, Sweden, Portugal, Austria and the UK.

For more information please visit the homepage http://sunpap.vtt.fi.

METALLIC SINTERABLE PAPERS – A FLExIBLE SEMI-FINISHED PRODUCT FOR POWDER METALLURgyDevelopments bridging the gap between different materials and technological sectors demand interdisciplinary partner-ships. True to this motto, PTS started a joint development project with the Fraunhofer Institute for Manufacturing and Advanced Materials (IFAM) to derive sintered metal struc-tures from paper.

The new technology will be based on specialty papers which can be enriched with sinterable metallic particles to be thermally converted into purely metallic structures. Metal particles will be added as fillers during papermak-ing, to obtain semi-finished products in the form of metal-lic sinterable papers which can then be transformed into paper-typical lightweight structures by paper-technological processes. The thermal conversion of paper structures is done in two

steps: Step one is the removal of cellulose fibres in a so-called debinding furnace. Because of its high filler content, the resulting semi-finished product is still strong enough for step two, the actual sintering at temperatures up to around 1400 °C. The sintering process forms a micro-porous metal-lic material in the previous paper structure, with cellulose fibres acting as pore forming material. Laboratory pre-tests have shown that papers can be filled with metal particles up to a level of 90 % by weight (Figure 1).The cross-sectional SEM image shows quite impressively how the microstructure is determined by metallic fillers. The metal particles are sufficiently close to each other to permit successful sintering. Fillers tested so far include special steel, molybdenum and copper particles in the size range of 5 - 20 µm; all papers filled with these metals could be successfully converted into metallic materials by thermal


treatment. Depending on the particle size and content of fillers and sintering sequence used, the degree of porosity can be controlled across a wide range in the metal obtained. So far, we have been able to reach porosity levels of 20 – 70 % by volume at medium pore sizes in the range of 5 to 200 µm (Figures 2 and 3).The new technology has sparked the interest of sintered metal producers - sinterable paper is an innovative semi-finished product for powder metallurgy. In particular the opportunity to obtain light-weight metallic structures de-rived from paper offers considerable application potential in areas like filtration, catalyst technology or heat manage-ment.The planned development follows in the footsteps of suc-cessful projects on paper-derived ceramics. The promising results achieved so far suggest that this project is going to succeed as well. It will bridge the gap between paper and sintered metal technology, providing sinter metallurgists with fully developed, established paper-technological solu-tions for exciting new projects.

Fig. 1: Cross-section of a specialty paper filled with special steel powder to a level of more than 85 % by weight, scanning electron microscopy (SEM), back-scatter mode: Light spots: special steel particles, dark areas: cellulose fibres

Fig. 2: Cross section (SEM image) of a copper-filled paper after thermal conversion (sintering), porosity of approx. 20 %

Fig. 3: Cross-section (SEM image) of a paper filled with special steel particles, after thermal conversion (sintering), porosity of approx. 70 %

Dr. Andreas Hofenauer 0049 89 12146 531 [email protected]

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PTS SyMPOSIUM WATER & ENVIRONMENT, 10TH - 11TH NOVEMBER 2009Since the kick-off PTS Water and Environmental Technology Symposium 30 years ago, water consumption has been reduced by more than two thirds and the energy demand has nearly been halved in the industry. These are great achieve-ments, but climate change and the call for resource-saving production are posing new challenges today. On its 30th an-niversary, the symposium therefore intends to present the latest findings and developments in research and industrial practice in the fields of water, energy and waste technology of paper production - as the basis for answers and solutions to future challenges. The symposium will be held in Munich/Germany.

Registration via Mail: [email protected] or PTS homepage: www.ptspaper.de


PERSPECTIVES OF BIOREFINERy CONCEPTS IN THE PAPER INDUSTRy

PTS scientists have carried out an INFOR study to identify the present chances and risks of biorefineries to the German pulp and paper industry.

Biorefineries are understood to be complex and integrated systems combining processes and equipment to produce a spectrum of bio-based products like materials, chemicals or fuels (no direct energy generation) from renewable raw ma-terials and convert them into non-food industrial end prod-ucts. Biorefineries make maximum use of the biomass, thus maximizing the value derived from renewable raw materi-als, and contribute substantially to sustainable economic development.Because they combine physical, bio-technological and chemical methods to break up and convert complex bio-masses, biorefineries are basically comparable to petroleum refineries (see Figure 1, Kamm et al. 2006). They have be-come highly important worldwide, and are also the focus of EU economic policy.The same definitions can be applied to pulp and paper production, which is in fact a textbook example of the im-plementation of biorefinery concepts and their goals. The renewable raw material wood is converted into pulps, pa-per, by-products (chemicals) and energy. Decades ago, es-pecially sulphite pulp mills were typical “biorefineries” as we understand them today, manufacturing lignin products, bioethanol and/or fodder yeast as well as other products in addition to sulphite pulps. Economic conditions demanded a change over, however, because sulphite pulping was in-creasingly superseded by kraft pulping. The focus of kraft

mills was on circuit closure and maximum chemical recov-ery in combination with energy generation. Furthermore, the demand for tall oil and turpentine decreased. PTS scientists have carried out an INFOR study to identify the present chances and risks of biorefineries to the German pulp and paper industry. Starting points for the papermak-ing sector can mainly be found in the competition for recov-ered paper to be used as raw material. More efficient fibre use, the development of new, environmentally compatible and resource-saving product designs, residue-free paper-making and the generation of new raw materials from stock

Material flow

Residues Paper making

Recovered PaperCollecting Systems

Consumer

Paper converter

Technologies Products

Biorefinery

Separation

Fractionation

Extraction

Modification

High QualityFibres

Low QualityFibres

PAPERhigher-quality product

Fibres materials

Chemicals

Plastics

Fuels

electricity, heat

Fig. 2: INFOR study “Biorefinery Study on a Joint Technology Initiative“ PTS 2009

Fuelsandenergy

Fuelsandenergy- bioethanol- biodiesel- biogas

Chemical industry

Material recycling,Chemical industry- basic and fine chemicals- biopolymers / plastics

Refinery Biorefinery

Petroleum Biomass

Fig. 1: B. Kamm, M. Kamm, P. Gruber (eds). Biorefineries: Industrial Processes and Products, Wiley-VCH, Weinheim (2006).


Installing a supplementary treatment stage downstream of the biology: PTS scientists carry out tests on membrane filtration and ozone treatment for clients from the paper industry.

Fresh water use and especially waste water treatment are major cost factors in paper production. Water will become ever more important on a world-wide scale, requiring the efficient use of existing resources. At the same time, paper mills are modernizing and enlarging their productions to survive in global competition. In many cases, this leads to higher waste water volumes and contaminant loads having to be clarified by the waste water treatment plant (WWTP). If this results in higher amounts of persistent COD in waste waters, the biological stage is often no longer capable of en-suring the statutory limit values. Higher organic loads in the waste water will usually not be approved by the authority. Advanced treatment stages become necessary if treated waste water is to be recirculated into the process or if the mill’s existing ETP can no longer cope with the increased waste water loads. Two methods are mainly used for this purpose today: membrane filtration and ozone technology.

Ozone technology Ozone technology is an important method for advanced waste water treatment, its main effect being the reduction in residual COD. Aim is the partial oxidation of residual organic loads. Ozone is added in such quantities that inert residual COD compounds are split to become biodegradable again. This can be measured by the decrease in COD and increase in BOD5. A low-load biological treatment stage is installed downstream of the ozone stage for BOD5- and fur-ther COD reduction. Residual COD reduction by means of this process combination is more economical that full oxida-

flows are both chances and challenges to the paper indus-try. By means of biorefinery concepts, previously unusable components like adhesives, binders, rejects or minerals can be converted into bio-based products.Figure 2 shows how biorefinery processes can be used to enhance the value derived from secondary raw materials, using recovered paper based paper production as an exam-ple. Only the fibres having the highest paper-technological po-tential are used for papermaking; the rest can serve as raw material for fuel production, for example. Non-paper com-ponents separated from the stock during recovered paper treatment can be used on their own or as by-flows for alter-native material uses in other industrial sectors.

The development, improvement and broad application of biorefinery concepts holds the key to the sustainable pro-duction of chemicals, materials and fuels. The paper in-dustry can contribute greatly to this, generating additional revenues.

Adrian Manoiu 0049 3529 551 680 [email protected]

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10 yEARS OF ADVANCED WASTE WATER TREATMENT By OzONE AND MEMBRANE FILTRATION – WHICH METHOD RANKS FIRST TODAy?

tion by ozone alone, COD levels can be reduced by up to 90 % this way. By choosing an appropriate ozone dosage, the process combination can achieve nearly any desired level of COD elimination. Plant enlargements based on this concept have already been implemented in practice; two full-scale systems have gone on steam. By means of approx. 100 g O3/m³ and a downstream biofilter, they can reduce COD levels by around 50 %. Recirculating the ozone-treated waste wa-ter into an existing biological stage is an additional option to eliminate the now biodegradable constituents, provided the biology can cope with the extra hydraulic load. Another important effect of ozone is decolouration. The typical brownish colour of paper mill effluents can be large-ly removed by ozone dosages far below the amounts neces-sary for COD reduction. Ozone can also be used to decolour process waters from coloured paper production. This ap-plication has already been implemented on full scale; the ozone dosages used are in the range between 15 and 50 g O3/m³.Waste water from pulp production or productions using wet strength agents based on epichlorohydrin often contains in-creased AOX concentrations. AOX reduction is another ef-fect of ozone treatment. Depending on the initial concentra-tion, 100 g/m³ ozone can eliminate up to 50 % of the AOX present. Various trace elements can be reduced by ozone treatment as well - details about this will be elaborated in a new joint R&D project of PTS and the Institution for Paper Science and Technology (IfP-GmbH) in Darmstadt.Apart from waste water and circulation water treatment, ozone can also be used to improve the settling properties of activated sludge in biological stages. It can be added to the activated sludge in the outlet of the activated sludge tank and to the return sludge. Laboratory tests have shown that ozone dosages between 7 and 10 or 15 g O3/g SS sludge


give the best results here. Paper mills can thus avoid the non-compliance with limit values due to degenerated and floating sludge and its associated costs.

Cost of ozone treatmentCapital costs of ozone treatment depend mainly on the ca-pacity required for ozone production – i.e. on the size of the ozone generator. Further cost factors are pumps, pipelines, residual ozone annihilation etc. The amount of ozone to be produced and, thus, resource costs (oxygen and energy) of ozone production depend on the COD load to be eliminat-ed. Pump energy is a further cost factor. In addition to the ozone stage for advanced waste water treatment, an aerobic low-load stage must be installed (a biofilter, for example). Despite this additional treatment stage, the process combi-nation is clearly more cost effective than the complete oxi-dation of residual COD by ozone alone because of its much lower running costs. PTS scientists have gathered extensive know-how and vast experience of ozone treatment in numerous research and service projects investigating the various objectives of ozone use by means of the laboratory ozone plant of PTS.

Membrane filtrationAmong the various membrane processes currently on the market, nanofiltration (NF) is the most suitable option for secondary clarification after biological treatment. With pore sizes of only 1 -10 nm, it permits filtration results exceed-ing the normal separation of particles by far. Apart from re-ducing turbidity, it removes many of the organic molecules, multivalent ions and colorants contained. Depending on the membrane used, this permits COD reductions in the range of 80 -98 %.The treated permeate cannot be distinguished from clean fresh water with the naked eye (cf. Fig. 2). Membranes

with even smaller pore sizes can remove nearly all water constituents including monovalent ions like chloride. This “reverse osmosis“ is used for sea water desalinization or boiler feedwater treatment, applications requiring higher pressures and energy inputs than nanofiltration, though. The treated permeate from NF can be used instead of fresh water for further circuit closure or to ensure the compliance with statutory discharge limits.

Less expensive but lower permeate quality: MBR A variation on this technology which is of current interest to environmental technologists and paper mill managers is the ”Membrane Bio Reactor“ (MBR). At least ten full-scale MBR plants are currently operated in European paper mills. Membrane bio reactors employ ultrafiltration (UF) units with a pore size between 0,1 and 0,2 µm to retain solids and microorganisms in the activated sludge tank of the biology. These clearly larger pores cannot retain dissolved organic compounds, salts or colorants, i.e. they are not capable of COD reduction. The MBR process is therefore an alternative to classic biological treatment, but no option for advanced waste water treatment.

Nanofiltration: a solution for partial streamsThe main advantage of nanofiltration or reverse osmosis is the excellent quality of treated water. Full-scale applications of this technology can already be found in two German pa-

per mills and in a few other paper-making companies abroad. The good treatment results do not come cheap, however - operating costs are quite high and several process-related risks and requirements must be taken into account. Because of its high costs, NF has only been an option for partial waste water streams so far - unlike ozone technology which is suitable for full-stream treatment. Another difference to ozone treatment is the fact that NF cannot be controlled to the same extent as ozone oxidation: ozone reactors can be turned on or off as required, which is only partly pos-sible in membrane filtration. A further drawback of NF is that wa-ter constituents accumulate on the feed side because they are removed

Abb. 1: PTS laboratory ozone facility

Fig. 2: Feed and permeate of nanofiltration


only physically rather than degraded. As a result, there is always a “concentrate” in addition to the clean permeate, accounting for approx. 3 to 15 % of the volume flow. At the point described, the concentrate flow contains refractory COD as well as multivalent ions like calcium, carbonate or sulphate. If the treatment is used for smaller partial streams only, recirculation into the biology might be a feasible op-tion. The NF of larger streams, however, requires a separate treatment step for concentrates causing extra costs as well. Suitable processes are precipitation, oxidative methods or – for small amounts - evaporation.

Cost of NF technologyCosts of NF include the operating costs of the membrane (approx. 1.00 to 1.50 EUR per m³ permeate for energy, chemicals, maintenance, personnel ...) as well as variable follow-up costs for concentrate treatment and preliminary filtration. Depending on the type of membrane used, the stability of the membrane process is decisively influenced by the preliminary filter type. As a rule of thumb: the finer the preliminary filter, the more stable and the less mainte-nance-intensive is the membrane filtration process. Mem-brane fouling, i.e. the formation of deposits on membrane surfaces, depends essentially on preliminary filtration. When using spirally wound modules, sand filters are the minimum standard for preliminary treatment. Apart from the common spirally wound types, there are also other membrane designs which are considerably less sensitive to suspended particles, but tend to consume more energy.

Comparison ozone vs. nanofiltration: which ranks first now?Both processes are basically suitable for advanced waste water treatment. Because of their completely different per-formance characteristics, decisions must be based on many more factors than economic efficiency alone. NF will be the method of choice if the effluent volume is to be reduced and the biological return water must be of high quality, for ex-

ample. Ozone technology is suitable for applications where the COD reduction of final effluents is prioritized, also if this must be done during alternating production intervals only. The main differences between the two methods are listed in the table below. Depending on boundary condi-tions, both technologies have their preferred applications. Experience of full-scale implementation has been available for about ten years now.

Membrane technology: PTS enlarges its portfolio for con-tract research in water technologyPTS scientists are investigating current technical questions concerning the use of NF technology to develop possible solutions for various contract research projects. A modern laboratory plant enables them to do continuous trials sim-ulating full-scale applications. The plant can be operated

Ozone Nanofiltration

Discharge quality „Adjustable“ COD concentration in the effluent•Colour reduction •

„Anything is possible“, i .e . from mere solids retention to drinking water quality, depending on the membrane type used

Pros

No secondary products •Optimal for full stream treatment•No additives left in the water•„Adjustable“ COD concentration in the effluent•

Excellent water quality through high retention of COD, •suspended particles, colorants, salts Optimal for treating / re-circulating partial effluent •streams

ConsNo salt reduction•BOD5 increase necessitates aerobic post-treatment for •direct discharge

Concentrate as secondary product •Uneconomical for full stream treatment•Difficult if water has high depositing tendency •(scaling)

Recirculation Possible, depending on the water quality required Possible without limitations permits increasing circuit closure

CostsDecisive factor: ozone quantity required (depending •on COD levels in the inlet and target COD)Extra costs: biofilter may be necessary•

Decisive factors volume flow and pressure•Extra costs: preliminary filtration; possibly also con-•centrate treatment

Table: Comparison of the two advanced treatment methods

Abb. 3: On-site use of the PTS membrane plant


automatically, using pressures of up to 15 bars. Its measure-ment, control and safety equipment also permit continu-ous trials to be done on site and with minimum operational support. The technology is now available to customers for laboratory and mill trials, complementing ongoing consul-tancy projects on water circuit optimization and waste wa-ter treatment in an effective way. Our service offers include feasibility studies, filtration tests or cost estimates in the field of membrane filtration.

Membrane technology in the paper industry: consultan-cy, research, trainingThe growing number of full-scale applications in Europe shows that membrane technology has gained considerable importance in the paper industry. Technical improvements have made membrane reactors much more stable, efficient and economical today. PTS offers its customers in the pa-per industry comprehensive consultancy and service work on this subject. Besides practice-oriented research, the ex-change of knowledge between membrane plant manufac-turers and their users in the paper industry is in great de-

mand. To meet this demand, PTS has launched the seminar “Membrane technology in the paper industry“, which will already be held for the second time on 4/5 May 2010. Fur-ther details of this seminar are available on our website, together with a “Call for papers“.

Membrane technology:Benjamin Simstich 0049 89 12146 388 [email protected]

Ozone technology:Svenja Bierbaum 0049 89 12146 144 [email protected]

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MONITORINg THE qUALITy AND COMPOSITION OF RECOVERED PAPER By MEANS OF NIR MEASURINg TECHNOLOgy

PTS scientists have been developing NIR methods for the in-coming quality control of recovered paper for several years. Solutions for quality evaluations of baled recovered paper and loose sorted graphics for deinking (1.11) have already been brought to market or stood the test in paper mills.

Further PTS research aims at developing an online method to continuously monitor the quality and composition of re-covered paper. With this method, PTS will be able to offer its customers in the paper industry a complete system of

evaluation tools from which they can choose according to their specific needs and demands.To assess the quality of baled recovered paper, the portable NIR Paper Bale Sensor (PBS) measures the amounts of ash, moisture, plastics and fibres contained. The device is also available as stationary system for automated operation.Loose sorted graphics for deinking are assessed by means of random samples (of more than 50 kg), which are led past the measuring device on a conveyor belt. An evalua-tion program classifies each object contained in the sample,

Fig. 1: Screenshot from an online measurement of RP composition. Each pixel (position on the conveyor belt) represents a mea-sured spectrum which has been colour coded in accordance with its classification results.


and determines the shares of sorted graphics for deinking, unwanted papers, non-paper components and flexographic newspapers as well as the ash and moisture contents. The principles and methods employed for the quality con-trol of sorted graphics for deinking can now also be used to continuously monitor the composition of loose recovered papers fed into a pulper or drum. NIR spectra are obtained online across the entire width of the conveyor belt, and classified according to recovered paper types or other com-ponents. The classified spectra can then be used to quan-tify and visualize the recovered paper composition and its changes (Fig. 1), and to determine material parameters like ash content (Fig. 2).The online measurement of recovered paper quality ahead of the stock preparation system permits prompt reactions to changes in recovered paper composition. Mill operators can thus optimally adjust their treatment stages to quality fluctuations caused by changing raw material composition, i.e. choose suitable process parameters to ensure that the finished stock reliably meets all quality demands. In a new research project, PTS scientists will join forces with partners from the industry to develop the prerequisites for implementing the concept of online recovered paper moni-toring. Tests will be done to record the material parameters of incoming recovered papers and their changes by means of NIR technology, in order to correlate them with process data from deinking. Parameters identified as relevant to the process will then be used for process control.By implementing these results, mill operators can enhance the process stability of their deinking plants for improved product quality due to:

more consistent quality•reproducible manufacturing processes•

Fig. 2: Screenshot of an online ash measurement

Dr. Enrico Pigorsch 0049 3529 551 678 [email protected]

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STRENgTH gAINS WITHOUT PULP REFININg

In a pre-research project, PTS scientists elaborated a con-cept how to develop paper strength by nano-technological fibre modification and formation of nano-fibre composites instead of refining.

Paper is a two-dimensional structure comprised of intercon-nected cellulosic fibres. Fibres are responsible for all main paper properties: structural, strength and – together with fillers - optical properties. Strength is the most important paper property: it is the prerequisite for successful paper-making, upgrading and converting and for ensuring the desired use value. High paper strength gives papermakers more leeway to save production costs – by either grammage reduction or increased use of fillers or recycled fibres. Paper strength is determined by the strength properties of single fibres as well as by the number and strength of bonds between fibres in the paper structure. This sets a limit to pa-

per strength as a function of grammage. Selecting suitable pulp types, preparation methods and fibre quantities per unit area of paper produced continue to be the main pre-requisites to achieve a desired strength property. However, the strength of single fibres is reduced by wood production, mechanical and chemical pulping, depending on the proc-ess design used: fibre structures will be destroyed locally by mechanical action, or chemically by degradation and the formation of low-molecular degradation products. Refining is the most important treatment step to produce bondable fibres today. Aim is the enlargement of bonding areas between fibres. However, this cannot be achieved without destroying the fibre structures: fines formation and fibre shortening effects increase the more intense the re-fining process is. The number and strength of inter-fibre bonds are thus increased at the cost of single fibre strength. Strength gains are connected to the apparent density of pa-

easier analysis of deviations •systematic plant and product optimization•

and for production cost savings due to:reduced consumption of chemicals, energy and water as •well as lower effluent volumesefficient performance data (efficiency, speed)•lower maintenance and repair costs •fewer complaints from customers due to off-spec •quality

12

ods (see the diagrams in Figures 1 and 2). The modification of fibre sur-faces alone was found to give only limited strength gains because it fails to produce the swelling and flexibility increase in fibre walls achieved by re-fining. Fibre modification is therefore more effective for strength develop-ment in papers made from hardwood pulps because they are finer than softwood pulps. A special advantage of this treatment is that the strength of single fibres remains unaffected, which makes it possible to achieve comparatively high dynamic strength values. Unlike refining, which can-not reach all fibres in the suspension,

modification reaches practically all fibres contained, thus ensuring more homogeneous results.Detailed results of this project will be presented at the PTS Pulp Sym-posium on 24 and 25 November in Dresden.

PTS NewS 03/2009 ReseaRch

per: The higher the refining intensity, the more dense are the fibre structures produced, the better the contacts be-tween fibres and the higher the tensile and delaminating strength of the paper, but the lower its opacity.The first step of pre-research project IW VF 080012 was laboratory tests investigating the following alternatives to refining:

Modification of fibre surfaces by means of carboxyme-•thyl cellulose (CMC)Alternating, multiple coating using cationic and anionic •polyelectrolytes (PEM Poly-Electrolyte Multilayer)Addition of cellulose microfibrils •

Aim was the development of paper strength so that refining can be omitted. Promising treatment variations were select-ed for pilot-scale papermaking trials using modified pulps in the PTS pilot plant. The results of these trials show that it is possible to achieve satisfactory paper strength by fibre modification, especially by using synergies between the various modification meth-

MFC: mikrofibrillierte CeFS: Füllstoff

Tens

ile In

dex

MD

/CD

[N

80

70

60

50

40

30

20

10

0

Eucalyptus grandis: Modifizierung vs. Mahlung

PEM-Modifizierung CMC + PEM-Modifizierung gemahlen, 24 SR

MFCFS

−−

−20%

5%−

5%20%

−−

−20%

5%−

5%20%

−−

−20%

Fig. 2: Tear index: comparison between unrefined, modified and refined eucalyptus pulps (PEM: by means of cationic and anionic starch, MFC: commercial product)

MFC: mikrofibrillierte CeFS: Füllstoff

Tear

Inde

x M

D/C

D [m

Nm

²/g]

109876543210

Eucalyptus grandis: Modifizierung vs. Mahlung

PEM-Modifizierung CMC + PEM-Modifizierung gemahlen, 24 SR

MFCFS

−−

−20%

5%−

5%20%

−−

−20%

5%−

5%20%

−−

−20%

Dr. Klaus Erhard 0049 3529 551 627 [email protected]

contact

Fig. 1: Tensile index: comparison between unrefined, modified and refined eucalyptus pulps (PEM: by means of cationic and anionic starch, MFC: commercial product)

Manuela Fiedler 0049 3529 551 620 [email protected]

Brit Gantze 0049 3529 551 801 [email protected]


Marburg terahertz group, winners of the Kaiser-Friedrich research award in 2003, among other, have vast experience with the design and construction of optoelectronic THz spectroscopy systems as well as with the dimensioning and design of THz system components. In addition, they have done detailed and fundamental research on how to quanti-tatively assess the signals produced, and have advanced the implementation of this technology up to its first industrial uses. PTS contributes many years of experience in paper technology, in particular the knowledge of fundamental re-lationships and of how to use new technologies to charac-terize innovative products and manufacturing processes.Envisaged result of this co-operation is an online system which is ready for near-industrial testing by the end of the project time. In the medium term, the new measuring sys-tems are expected to supersede the still common but prob-lematic radiometric methods and to enable more consistent and low-reject productions as well as material and energy savings.

NEW LIgHT CAST ON SPECIALTy PAPERS

PTS and Marburg University launch joint research project to develop new measuring system for multiple coated papers and plastic composites.

Last August, a new research co-operation was given the of-ficial go-ahead by the first meeting of the project support committee. More than a dozen high-ranking representatives of companies dealing with metrology development and ad-aptation as well as producers of various specialty papers met with scientists from PTS and the research group for ex-perimental semiconductor physics at the Faculty of Physics in Marburg to discuss the main features and detailed goals of a new IGF project.Project aim is the development of a new measuring method to determine the thickness and grammage of individual lay-ers in multiple coated papers. It focuses, among other, on multiple coated or plastic-coated papers and multiply plas-tic composites, products which are increasingly being used today. The method must be capable of measuring these pa-rameters online directly after coating, allowing conclusions to be drawn about the types and dimensions of individual layers.It will be based on terahertz spectroscopy, a method which has also been discussed in other contexts. The Marburg research group was the leading contributor to develop-ments of practically applicable components and complete measuring systems in recent years, which have paved the way for industrial applications available today. Unlike X-rays, terahertz waves are capable of screening materials in a nonhazardous way because they have no ionizing effect. Furthermore, they are strongly absorbed by water and will therefore not penetrate deeply into the human body. An-other advantage is the typically minuscule radiant power of the systems used.The joint project will combine the core competencies of PU Marburg and PTS in an ideal way. The scientists of the

Dr. Patrick Plew 0049 3529 551 666 [email protected]

contact

PTS-SEMINAR: ANALyTISCHE BEWERTUNg VON FASERSTOFFENDas Seminar findet am 1. - 2. Dezember 2009 in der PTS in Heidenau statt. Es vermittelt neben theoretischen Grund-lagen auch praktische Anwendererfahrungen. Weiterhin zeigt der Kurs Wege auf, wie in den Papierfabriken mit relativ einfachen Mitteln Faserstoffanalytik praktiziert und die Ergebnisse bewertet werden können.

Anmeldung unter [email protected] oder auf der PTS-Homepage www.ptspaper.de

14 PTS NewS 03/2009 customeR PRojects

CALENDER DESIgN BASED ON PRE-TRIALS IN THE PTS PILOT PLANT

A pilot-scale sheet calender was developed in a joint project of PTS and the company PAMA Papiermaschinen GmbH based on pre-trials in the PTS pilot plant in Heidenau.

Paper surfaces meeting the demands of special applications are produced by thermo-mechanical surface treatment com-monly referred to as calendering. Calendering usually re-duces the surface roughness of paper, causing the specific volume to be slightly reduced as well. Another key aspect is the adjustment of smoothness ratios between wire and felt side. PAMA Papiermaschinen GmbH is a company specializing in paper machine construction and rebuilds. This includes also the provision of specially adapted machine calenders, whose design and dimensioning requires both technological know-how and information about the effects of roll mate-rial, temperature, paper moisture, surface pressure and nip dwell time on the surface properties of paper. Pilot-scale systems for investigating these issues are very expensive. The best way to lower risk of these investments is pilot-scale pre-trials. Experts from PAMA and PTS Heidenau have therefore joined forces to build a pilot-scale sheet calender-ing system for low-cost pre-trials.

Aims of the trials Identifying the design data of a machine calender meeting the following demands:

suitable for thin papers in the grammage range of 30 - 50 •g/m²machine speeds in the range of 400 m/min•smoothness ratio ahead of the calender: 0,5 - 0,7•smoothness ratio after the calender: larger than 1,5•total smoothness gain as low as possible, especially on •the wire side

The following information was to be gathered by the trials: suitable material of the soft roll•pressing power required as a function of radii soft roll/•hard roll for 400 m/min machine speed

Trial programme and methodologyPre-trials of papers provided by PAMA were conducted on the pilot calender of PTS Heidenau, using the following steps:

Identifying the effects of nip dwell time and surface pres-1. sure on smoothness ratios, using the mating rolls avail-able at PTS (chilled iron roll/chilled iron roll and chilled iron roll/plastic rolls of different hardness levels).Identifying the demands on the surface quality of a plas-2. tic roll manufactured specifically for this application (to-gether with a roll cover manufacturer).Using the specially produced plastic roll to determine the 3. effects of nip dwell time and surface pressure on smooth-ness ratios.Transfer of test results to industrial applications.4.

Fig. 1: PAMA Papiermaschinen GmbH

15PTS NewS 03/2009 customeR PRojects

The results of these investigations were used by PAMA Papier-maschinen GmbH to design and test the full-scale system.

Test stand: pilot calenderThe test stand at PTS Heidenau makes it possible to do cal-endering, calibration and glazing trials at low cost, requir-ing only small amounts of test material.The pilot system is a sheet calender using the common sheet size of 70x30 cm. A special feature is the feeding of sheets into the open nip between rolls. The nip closes upon receipt of a signal from a detection system, and the full pressing power is applied after 10 cm. This prevents the common press marks on soft rolls.Parameters relevant to calendering are:

nip width,•surface pressure and•nip dwell time.•

These can be calculated from the parameters:operating speed,•linear force at constant parameters,•machine parameters (radii of hard and soft rolls) and•roll parameters (elastic moduli and Poisson ratios of •rolls).

The test results can be extrapolated to obtain sufficiently accurate design data for full-scale systems.

Summary of resultsAs a first step, we investigated how the smoothness ratio is influenced by the roll material and paper side facing the function roll. The test results (Figure 4) have shown that:

the smoothness ratio remains more or less the same •when using mating rolls made of chilled iron both,the smoothness ratio can be changed in the desired di-•rection by using a plastic roll facing the wire side of the paper,the smoothness gains produced by the rolls used in the •trials were too high on both sides of the paper.

It was therefore necessary to develop a new roll cover spe-cifically for this application, which was done together with a roll cover manufacturer. Using this cover (C X), a new roll

Fig. 2: Calender test stand

Sheet-fed process max . 500*1000 mm

Operating speed 3 - 30 m/min

Maximum linear force 200 kN/m

Maximum surface pressure 60 N/mm²

Calender nip heating/function roll

Heating and backing roll: bottom position (chilled iron)

Diameter 400 mm

Heating Ext . Elektro – IR- Heizung

Surface temperature 20 . . .250 (…350)°C

Function rolls

glazing

Hard paper/cotton/wool cover 80 . . .92°ShD

Soft calendering

Fibre/plastic cover 62 . . .91°ShD

Calibrating

Chilled iron roll 72°ShC; 550HV

Fig. 3: Calender test stand – technical data

Smoothness ratio (Bekk) as a function of roll type

0.6 1.1 0.8 0.60.6 1.2 2.4 2.30.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

without smoothness chilled iron 72 Shore C plastic 10 P&J plastic 88 Shore D

Roll type/hardness

Sm

ooth

ness

rati

o

FS to function roll WS to function roll

Smoothness FS: 11 sWS: 19 s




Fig. 4: Smoothness ratio as a function of roll material


was build for the PTS calender and tested to determine the effects of nip dwell time and surface pressure on smooth-ness development on wire and felt sides.Figure 5 shows that increasing surface pressures and nip dwell times give higher smoothness gains on the wire side as compared to the felt side. Based on these results, the de-sign configuration of the calender was calculated, namely

ratios between the radii of soft and hard rolls and •hardness and surface roughness of the soft roll.•

The calculation results were confirmed by the results of the start-up phase (Figure 6). Because the felt side smoothness was still too high, the surface roughness of the soft roll was increased (Ra of approx. 1,5 µm). After this modification, the desired smoothness ratio could be achieved with a mini-mum increase in FS smoothness.The results of this joint project enabled PAMA to design, build and start up the machine calender at minimum risk. All target parameters could be reached shortly after start-up.

3 4 5 5 68 9

13

20

2427

3033

0

20

40

60

80

100

120

140

160

180

22 31 22 38 31 38 22 31 38 50 59 67 74 80

Surface pressure in N/mm²

Bekk

sm

ooth

ness

in s

0

5

10

15

20

25

30

35

40

Nip

dw

ell t

ime

in m

s

Forecast

Nip dwell timeSmoothness WSSmoothness FS

Forecast - smoothness as a function of surface pressure and nip dwell (Roll cover C X 1)

Ratio1.1

Ratio1.2

Ratio1.3

Ratio1.4

Ratio1.5

Ratio1.6

Ratio1.8

16

0

20

40

60

80

100

120

140

0 10 20 30 40 50 60 70 80

Nip pressure in kN/m

Bekk

sm

ooth

ness

in s

Smoothness WS C X 2 Smoothness FS C X 2 Smoothness WS C X 1 Smoothness FS C X 1

Smoothness ratio 1.8 - 2.0

Smoothness ratio 0.6

Working range

Smoothness ratio 1.4 - 1.5

Start up - smoothness as a fuction of nip pressure(Roll cover C X 2 higher roughness)

Fig. 5: Results of the optimization trials

Fig. 6: Results of the start-up phase

Dr. Herbert Berger 0049 3529 551 660 [email protected]

Projektpartner:Günter Borsdorf PAMA Papiermaschinen GmbH [email protected]

contact


The studies described below were carried out at the PTS pilot plant for innovative fibre upgrading and papermaking processes in Heidenau on behalf of the Amberger Kaolin-werke EDUARD KICK GMBH&CO KG, Danisco Deutschland GmbH, Omya International AG and Schaefer Kalk GmbH & Co. KG.

The use of fillers in paper has a positive effect on most pa-per properties such as opacity, gloss, smoothness, printabil-ity and even the profitability of the papermaking process.Increasing the amount of filler in the paper, however, is limited by the strength required, especially IWWS (initial wet web strength), among other factors. Insufficient IWWS frequently causes web breaks and a concomitant decline in paper machine productivity. It is therefore important to increase the share of long fibre pulp when increasing the amount of filler to thus maintain the strength level. That however lowers profitability.This explains why work has been carried out ever since the 1970s on a number of systems designed to increase fibre-filler bonding. One method involves activating fillers with chemical additives to improve fibre-filler bonding. There has been as yet no system that has successfully gained ac-ceptance either from a technical and/or economical point of view.

Study objectives The filler/additive system was to be optimised using prod-ucts from Danisco Deutschland GmbH with the aim of en-hancing fibre-filler bonding and thus increasing the amount of filler in the paper without any loss of strength.Another objective of the study was to formulate practice-oriented statements that reveal how retention, strength and optical properties are influenced as a function of

the stock model,•the additive system used to activate the filler, and•the type and amount of filler.•

One focus of the study was to determine how IWWS is influ-enced by the additives used. A decrease in IWWS causes the runnability of the paper machine to decline. This is an essen-tial criterion for restricting the amount of filler in paper.In the end, recommendations were to be derived for the industrial scale-up of the results regarding the additive/filler systems to be used for the stock models studied. Three stock models were selected for these studies with the fol-lowing filler increases being aimed at:

SC – paper A on a chemical pulp-mechanical pulp basis •of 52 g/m², 40% kaolin/60% GCC/PCCfrom 34% to 39% filler contentSC – paper B on a chemical pulp-DIP pulp basis of 52 g/•m², 40% kaolin/60% GCC/PCCfrom 32% to 37% filler content

copy paper on a 80% hardwood/20% softwood basis of •80 g/m², 100% GCC/PCCfrom 24% to 29% filler content

Trial programme and study methodologyThe fillers were activated by charging or reversing the charge of the filler surfaces by means of chemical additives in the filler slurry. The trials were carried out at the PTS pilot plant in Heidenau in two phases:

Suitable additive/filler combinations and additive vol-1. umes were chosen in the preliminary studies. The crite-ria used were IWWS (initial wet web strength) and how the flow behaviour/pumpability of the treated filler sus-pensions was influenced.Based on the results of these studies, the second trial 2. phase involved studying the impact of selected filler/additive combinations on flowability (initial wet web strength, dewatering and drying behaviour) and on pa-per properties with optimised settings for the type and volume of additive and type of filler.

Filler selectionKaolins, natural calcium carbonates and precipitated cal-cium carbonates were used. One aim of the studies was to investigate the impact of different dispersion and filler morphology on the effect of filler activation. The fillers that were examined are compiled in Table 1.

Additive selectionThe additives from Danisco Deutschland GmbH as com-piled in Table 2 were chosen from a number of possible additives.

Papermaking/Test benchThe experimental studies were carried out on the PTS pi-lot paper machine in Heidenau. The possibilities for dosing fillers and additives in the stock approach system made it possible to set defined reaction times between the pulp sus-pension/additives and fillers (Figure 1).

USINg CHEMICALLy ACTIVATED FILLERS TO INCREASE THE AMOUNT OF FILLER IN COPy PAPER AND SC PAPER

Table 1: Characterisation of the fillers used

Project ID Fillers - type Used for

A Kaolin from location A SC A + B

B Kaolin from location B SC A + B

C gCC slurry without dispersant

SC A + B + copy paper

D PCC slurry type 1 SC A + B

E PCC slurry type 2 Copy paper

F PCC slurry, scalenohe-dron with 35% aragonite

SC A + B

g PCC powder scaleno-hedron

Copy paper

18

The following is a discussion of the influence of the fill-er/additive combinations on initial wet web strength and surface strength (pick resistance or pick strength). Since it influences runnability, initial wet web strength is an impor-tant criterion for a possible increase in the amount of filler in the paper.

Paper testingThe parameters relevant for the respec-tive paper quality were studied. The SC paper was examined after calender-ing to a predetermined roughness. The copy paper was calendered in the ma-chine calender to a comparable rough-ness (5 µm PPS) prior to examination.In order to determine initial wet web strength, samples were taken after wet pressing at three different compression loads. The wet tensile strength and solids content were determined using these samples. The following factors were evaluated:

wet tensile strength as a function of •the solids content, andwet tensile strength interpolated at •an average solids content in order to ensure comparability of the trial series.

Summary of results

PTS NewS 03/2009 customeR PRojects

Table 2: Characterisation of the additives used

Project ID Additive - type Used for

Additive A galaktomannan phosphoric acid ester; anionic

Kaolin; gCC; PCC

Additive B galaktomannan deriva-tive; cationic

Kaolin; gCC; PCC

Konstantteil der Papiermaschine - Dosierung der Füllstoffe und Additive

Stoffpumpe

zum Stoffauflauf

Rundverteiler

DynamischerMischer

Maschinen-bütte200 l

Stoff von Mischbütte

Dosier-stelle 2

Probenahme

Reaktionszeit in s (durch Schlauchllänge einstellbar)

Dosier-stelle 1

FlFlFlFlFl

Füllstoff 1

Dosier-stelle 3

FlFlFlFlFl

Retentionsmittel

FlFlFlFlFlFlFlFlFlFlFlFlFlFlFl

FlFlFlFlFlFlFlFlFlFlFlFlFlFlFlFlFlFlFlFl

Dosier-pumpe 1

Dosier-pumpe 3

Dosier-pumpe 2

Füllstoff 2

StatischerMischer

Fig. 1: Dosages of fillers and process chemicals

50

40

30

20

10

0

Ash

cont

ent [

%]4.0

3.0

2.0

1.0

0.0without

F (PCC slurry)A (anionic)

F (PCC slurry)without

G (PCC powder)B (cationic)

G (PCC powder)

Additive type/Filler type

Init

ial w

et te

nsile

str

engt

h [N

]

Initial wet tensile strength interpolated (Tg 40%) vs. Fillers and Additives

2428

2328

3.0 3.6 2.9 3.3

IWWS Ash content

Fig. 2: Copy paper - initial wet tensile strength

50

40

30

20

10

0

Ash

cont

ent [

%]0.8

0.6

0.4

0.2

0.0without

E (PCC slurry)A (anionic)

E (PCC slurry)without

G (PCC powder)B (cationic)

G (PCC powder)

Additive type/Filler type

Pick

str

engt

h [m

/s]

Pick strength vs. Fillers and Additives

2428

2328

0.62 0.49 0.63 0.41

Pick strength Ash content

Fig. 3: Copy paper – pick strength

19

Copy paperThe use of additives A and B made •it possible to increase the amount of filler to 4 % while at the same time increasing initial wet web strength (Fig. 2).The surface strength, however, de-•teriorated by approx. 20% when filler E was used and by 35 % when filler G was used (Fig. 3). NB: The paper had been produced without surface sizing.The different types of PCC that •were used showed only minor dif-ferences.When additives were used, the de-•waterability of the fibre network decreased in the wet presses.

SC-A paper – Kaolin activationThe use of kaolin B resulted in •higher initial wet web strength than when kaolin A was used. Activat-ing kaolin B with additive B kept the initial wet web strength at the same level, although there was only 5% more filler. If kaolin A was used, the initial wet web strength declined, even if the amount of filler was increased by 28% despite activation (Fig. 4).The pick strength decreased by ap-•prox. 5% irrespective of the type of kaolin used and even with a greater amount of filler (Fig. 5).

SC-A paper – GCC/PCC activationThe effect of the additive B on the •initial wet web strength depended significantly on the type of GCC/PCC used. When filler D was used, even when the amount of filler was increased by approx. 5%, initial wet web strength reached a level com-parable to that in the comparison trial. If filler F was added, the same level was reached. By comparison, the use of filler C caused the initial wet web strength to decrease by ap-prox. 20% (Fig. 6).Due to the greater amount of filler, •the pick strength declined by ap-prox. 2% (in the case of filler C) to


50

40

30

20

10

0

Ash

cont

ent [

%]2.0

1.5

1.0

0.5

0.0withoutKaolin B

BKaolin B

withoutKaolin A

BKaolin A

Additive type/Kaolin type (Filler 2: PCC E without activation)

Init

ial w

et te

nsile

str

engt

h [N

]

Initial wet tensile strength interpolated (Tg 38%) vs. Filler and Additives (Kaolin activation)

35

4034

40

1.7 1.6 1.5 1.1

Wet tensile strength Ash content

Fig. 4: SC-A paper - initial wet tensile strength – kaolin activation

50

40

30

20

10

0 Ash

cont

ent 5

25 °

C [%

]

0.5

0.4

0.3

0.2

0.1

0.0withoutKaolin B

BKaolin B

withoutKaolin A

BKaolin A

Additive type/Kaolin type (Filler 2: PCC D without activation)

Pick

str

engt

h [m

/s]

Pick strength vs. Fillers and Additives (Kaolin activation)

35

40

34

40

0.38 0.34 0.37 0.34


Fig. 5: SC-A paper – pick strength – kaolin activation

50

40

30

20

10

0

Ash

cont

ent [

%]2.0

1.5

1.0

0.5

0.0without

D (PCC Slurry)B (cationic)

D (PCC Slurry)without

C (GCC Slurry)B (cationic)

C (GCC Slurry)without

F (PCC Slurry)B (cationic)

F (PCC Slurry)

Additive type/GCC/PCC type (Filler 2: Kaolin A without activation)

Init

ial w

et te

nsile

str

engt

h [N

]

Initial wet tensile strength interpolated (Tg 38%) vs. Filler and Additives (GCC/PCC activation)

34

40

35

40

33

39

1.5 1.5 1.6 1.3 1.7 1.6


Fig. 6: SC-A paper - initial wet tensile strength - GCC/PCC activation

50

40

30

20

10

0 Ash

sont

ent

525

°C [%

]

0.60.50.40.30.20.10.0

withoutD (PCC slurry)

B (cationic)D (PCC slurry)

withoutC (GCC slurry)

B (cationic)C (GCC slurry)

withoutF (PCC slurry)

B (cationic)F (PCC slurry)

Additive type/GCC/PCC type (Filler 2: Kaolin A without activation)

Pick

str

engt

h [m

/s]

Pick strength vs. Fillers and Additives (GCC/PCC activation)

34

4035

40

33

39

0.37 0.35 0.43 0.42 0.42 0.38


Fig. 7: SC-A paper – pick strength - GCC/PCC activation

20

10% (filler F) (Fig. 7).SC-A paper – Kaolin and GCC/PCC activationAs a means of orientation, the activa-tion of both filler components was ex-amined during the preliminary trials. The results did not justify continuing such studies.

SC-B paper – Kaolin activationDue to the change in the filler used •and the lower filler level, the initial wet web strength was higher for SC-B than for SC-A paper.The tendency here was the same •findings as in the case of SC-A. When activated with kaolin B, initial wet web strength reached the level of the comparison trials, even with a greater amount of filler. When kaolin A was used, there was a reduction of approx. 27% (Fig. 8).The pick strength of the compari-•son trials with SC-B paper without activation was approx. 25% higher than the pick strength with the SC-A paper. The decline in pick strength due to the 5% higher amount of filler was not compensated for by the additives used. There were no differences between kaolins A and B (Fig. 9).

SC-B paper – GCC/PCC activationUnlike the results obtained with •SC-A paper, the effect of the filler type on initial wet web strength was trivial with this stock model. The initial wet web strength level did not reach that of the compari-son trials in any of the trials even with a greater amount of filler. The decreases in initial wet web strength ranged from 13% (with filler C) to 20% (fillers D and F) (Fig. 10).By comparison, significant differ-•ences between the fillers became evident in their capability to affect pick strength (Fig. 11). Pick strength declined the least (5%) when filler F was used. The greatest reduction was seen with filler D (25%).

Conclusions drawn from the studiesThe findings obtained during the


50

40

30

20

10

0

Ash

cont

ent [

%]4.0

3.0

2.0

1.0

0.0withoutKaolin B

BKaolin B

withoutKaolin A

BKaolin A


Init

ial w

et te

nsile

str

engt

h [N

]

Initial wet tensile strength interpolated (Tg 38%) vs. Fillers and Additives (Kaolin activation)

3338

3238

2.6 2.6 3.1 2.3


50

40

30

20

10

0

Ash

cont

ent [

%]0.6

0.50.40.30.20.10.0

withoutKaolin B

BKaolin B

withoutKaolin A

BKaolin A


Pick

str

engt

h [m

/s]

Pick strength vs. Fillers and Additives (Kaolin activation)

3338

3238

0.5 0.3 0.5 0.3


50

40

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20

10

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cont

ent [

%]4.0

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D (PCC slurry)B (cationic)

D (PCC slurry)without

C (GCC slurry)B (cationic)

C (GCC slurry)without

F (PCC slurry)B (cationic)

F (PCC slurry)

Additive type/PCC/GCC type (Filler 2: Kaolin A without activation)

Init

ial w

et te

nsile

str

engt

h [N

]

Initial wet tensile strength interpolated (Tg 38%) vs. Fillers and Additives (GCC/PCC activation)

32 36 32

39

3137

3.1 2.5 3.0 2.6 3.0 2.4


40

35

30

25

Ash

cont

ent [

%]0.6

0.50.40.30.20.10.0

withoutD (PCC slurry)

B (cationic)D (PCC slurry)

withoutC (GCC slurry)

B (cationic)C (GCC slurry)

withoutF (PCC slurry)

B (cationic)F (PCC slurry)

Additive type/PCC/GCC type (Filler 2: Kaolin A without activation)

Pick

str

engt

h [m

/s]

Pick strength vs. Fillers and Additives (GCC/PCC activation)

0.50 0.38 0.53 0.44 0.52 0.49


Fig. 8: SC-B paper - initial wet tensile strength - kaolin activation

Fig. 9: SC-B paper – pick strength – kaolin activation

Fig. 10: SC-B paper - initial wet tensile strength - GCC/PCC activation

Fig. 11: SC-B paper - pick strength - GCC/PCC activation

21

project indicated that the selective use of filler/additive combinations based on guar are capable of increasing the amount of filler in paper while at the same time maintain-ing initial wet web strength. The surface strength (pick strength or pick resistance) was reduced by at least 5% in most cases. The optimum combinations of filler type/addi-tive type are dependent on the stock model. Recommenda-tions for the respective stock models were developed based on the results of the studies (Tables 3 to 5). The expression "only recommended conditionally" is understood to mean that chances are seen for further improvement using this particular filler/additive combination if optimisation (e.g. amounts added) is continued.The findings obtained in these studies make it possible for contracting parties from the industrial sector to implement the results obtained together with paper mills in a selective manner.


Filler - additive - combinations copy paper

Fillers Additives

Project ID Filler type Additive A (anionic) Additive B

"galaktomannan phosphoric acid ester; anionic "

galakto-mannan derivative; cationic

Filler E PCC slurry type 2

only recommended conditionally - pick strength?

not exa-mined

Filler g PCC powder scalenohe-dron

not examined only recom-mended conditio-nally - pick strength?

Filler - additive - combinations SC-A

Fillers Additive

Project ID Filler type Additive B

galaktomannan deriva-tive; cationic

Part 1 Activation kaolin - PCC without activation

Filler A Kaolin from location A cannot be recommended

Filler B Kaolin from location B only recommended conditionally - pick strength?

Part 2 Activation gCC/PCC - Kaolin without activation

Filler C gCC slurry without dispersant

only recommended conditionally - IWWS?

Filler D PCC slurry type 1 recommended

Filler F PCC slurry, scalenohe-dron with 35% aragonite


Filler - additive - combinations SC-B

Füllstoffe Additive

Project ID Filler type Additive B

galaktomannan deriva-tive; cationic

Part 1 Activation kaolin - PCC without activation

Filler A Kaolin from location A cannot be recommended

Filler B Kaolin from location B only recommended conditionally - pick strength?

Part 2 Activation gCC/PCC - Kaolin without activation

Filler C gCC slurry without dispersant


Filler D PCC slurry type 1 cannot be recommended

Filler F PCC slurry, scalenohe-dron with 35% aragonite

only recommended conditionally - IWWS?

Table 3: Filler-additive combinations for copy paper - evalu-ation

Table 4: Filler-additive combinations for SC-A paper - evalu-ation

Table 5: Filler-additive combinations for SC-B paper - evalu-ation

Dr. Herbert Berger 0049 3529 551 660 [email protected]

Project partners:

contact

Christian KohlAmberger Kaolinwerke Eduard Kick GmbH & Co. KG [email protected]

Edward NowakDanisco Deutschland GmbH [email protected]

Maximilian LaufmannOmya International AG [email protected]

Klaus HoelzerSchaefer Kalk GmbH & Co. KG [email protected]


KLINgELE MILL REDUCES ENERgy COST By MEANS OF THESySTEMCHECK ENERgy®

By the end of 2008, PTS was assigned to conduct an analy-sis of the Klingele paper mill in Weener to improve the mill’s energy efficiency. The consultancy project led to 27 single measures having payback periods of around one year. The implementation of these measures will enable KLINGELE to further reduce its energy consumption.

TaskAlso for Klingele Papierwerke GmbH & Co. KG, energy con-sumption has been a key issue for quite some time. Being an innovative company open-minded about new techno-logical approaches, Klingele has already made intense ef-forts to lower its energy costs – and with great success. The construction of a new RDF power plant is just one example of this. However, the mill is not yet satisfied with the results achieved so far, and has therefore brought PTS on board to have an external consultant assess its energy situation and efficiency and identify new ways of reducing the energy consumption even further. Klingele Weener produces two-ply corrugating base paper from 100% recovered paper. The mill’s production capacity amounts to 250,000 tons. The PTS study aimed at analys-ing and assessing the mill’s overall energy situation from generation to single consumers was subdivided into the fol-lowing steps:

documentation and assessment of the situation as-is•comparison with other plant systems•identification of potential savings•measures to realize these savings•

ApproachThe PTS SystemCheck Energy is a technological consul-tancy tool of PTS which assesses the energy efficiency and identifies potential savings. Key element is a comprehen-sive, systematic procedure based on methodologies proven by numerous investigations. The SystemCheck is capable of assessing the site in its entirety, thus enabling the maxi-mum use of synergetic effects across existing boundaries of the system.

Project resultsA comparison with other producers of corrugating base pa-per has shown that the total specific energy consumption of KLINGELE is very low already. The mill’s heat consumption is below the grade-specific average, its power consumption on a medium level as shown in Figure 1.Despite the mill’s already favourable energy situation, the systematic approach of the PTS SystemCheck Energy re-vealed new potential savings. The majority of measures were proposed for ventilation, steam and condensate sys-tems as well as pumps and drives.

Vacuum systemKLINGELE uses mainly water ring pumps for vacuum gen-eration. In the period investigated, the sealing water tem-perature was above the typical level. Temperatures between 20 and 30 °C would be ideal to increase the efficiency and service life of pumps and avoid cavitation. Reduced sealing water temperatures permit higher intake volumes. The air intake can be adjusted to the actual demand by lowering the pump speed via changes in the speed ratio. By decreas-ing the sealing water temperature, KLINGELE will be able to considerably lower the specific energy consumption of its vacuum system. The payback period for this measure is less than two years, taking into account the investment costs of cooling tower construction and speed ratio adjustments.

Steam and condensate systemInsulation of steam and condensate pipelines is state of the art today. Not always, however, are the fixtures, fittings and control valves consistently insulated – especially if they are difficult to access. A detailed list of the components includ-ing their precise positions, photographs and infrared im-ages, was handed over to KLINGELE in a separate report. Investments for proper insulation usually pay off within a year when considering all measures on average.Heat losses of an idle air condenser were visualized by a

Klingele Average of other CBP producers

heat power

spec

ific

ener

gy c

onsu

mpt

ion

Fig. 1: Comparison of specific energy consumptions Fig. 2: Heat losses caused by leaky fittings of the air condenser


thermal imaging camera: Reason for the losses was a leak-ing blow-through valve displayed as “closed” in the process control system. Losses like these are difficult to detect dur-ing operation, especially if the components concerned are in remote positions.

Ventilation systemAn air compressor converts approx. 92% of its power in-put into heat. For this reason, compressor rooms must be equipped with good ventilation. Utilizing the waste heat would make sense as well. PTS recommended supplying the hot exhaust air of the compressors directly to the ma-chine hood to reduce the share of cold leakage air entering the hood from the hall. This measure permits significant reductions in steam consumption.

Compressed air systemRegarding the compressed air system, PTS recommended reducing the current system pressure even further.

SummaryAll in all, 27 single measures were developed and economi-cally assessed. The majority of measures identified (see Fig-ure 3) have pay-back periods of less than two years. The consultancy project revealed further potential savings in the mill, making practical recommendations how to realize them.The project results have shown that systematic and com-prehensive analyses make it possible to identify economi-cally attractive potential savings also in plant systems with already low specific energy consumption. To realize this po-tential, the measures proposed must be implemented sus-tainably, monitoring their success continuously. After all, the efficient use of energy is one of the factors determining the economic efficiency of a mill.

Payback 2a

Payback 3a

Payback 10

a

Payback 1a

1

10

100

1.000

1 10 100 1.000

Investments / k€

Savi

ngs

/ k€

/aSteam and condensate systemHood ventilation Pumps and drivesVacuum systemCompressed airEffluent treatment plant

Fig. 3: Portfolio of measures

Daniela Römer 0049 89 12146 224 [email protected]

contact


PTS “VIRTUAL FRACTIONATION” SOFTSENSOR SUCCESSFULLy INSTALLED AT NORSKE SKOg

Having integrated the software platform into its operation environ-ment, Norske Skog is now automati-cally calculating fibre fractions sev-eral times a day (see Fig. 1) based on data obtained from fibre length analysis. The quality of the TMP pro-duced can be monitored in this way to ensure significantly enhanced test consistency. Manual laboratory frac-tionation used to be both time- and resource-consuming but now is a thing of the past.To quote Dr. Hucke (Norske Skog Fo-cus AS), “After extensive evaluation, we are convinced of the reliable re-sults obtained with the software and are working together with L&W and PTS on discovering other ways of us-ing the software in our production system (Fig. 2).Technical details and background on the implementation and use of fibre length analysis and the PTS SoftSen-sor within the scope of quality assur-ance will be addressed in a lecture by Norske Skog at the PTS Pulp Sympo-sium in Dresden on 24-25 November 2009.

Mas

s fr

actio

n in

%

60

50

40

30

20

10

0R14 R14

Soft-McNett

R30 R30Soft-

McNett

R50 R50Soft-

McNett

R100 R100Soft-

McNett

R200 R200Soft-

McNett

D200 D200Soft-

McNett

Fig. 1: Example of the automated calculation of fibre fractions

Fig. 2: Comparison of manual McNett fractionation and PTS SoftMcNett

Sven Altmann 0049 3529 551 634 [email protected]

contact

The PTS SoftMcNett SoftSensor that was launched at the Zellcheming 2009 has been enhancing Lorentzen&Wettre FiberT-ester’s at Norske Skog in Duisburg-Walsum since June of this year.

PTS PULP SyMPOSIUM, 24TH - 25TH NOVEMBER 2009 IN DRESDENThe symposium gives an overview of the current spectrum of globally available pulps and development trends. Contribu-tions on pulp use will centre on the product groups specialty papers, high-quality graphic papers and packaging papers, but will include applications of fibre composites as well.

Registration via mail: [email protected] or PTS homepage: www.ptspaper.de


Small and medium sized enterprises in Saxon may proft from a new programme promoting the tranfer of innovative technologies - PTS is supporting the companies both as a technology-giver and as a technology intermediary organi-sation.

The State Ministry for Economic Affairs and Labour (SMWA) is promoting the transfer of innovative technologies in small and medium sized enterprises (SMEs) in the State of Sax-ony. Carsten Stuhldreher from the SWMA's Department of Technology Policy and Technology Promotion explained the possibilities promotion schemes to representatives of Saxon papermakers on 19 August 2009. The meeting was organ-ised by the Association of East German Paper Mills e.V.Mr Stuhldreher made clear that funding is intended to en-able small and medium sized companies to integrate ul-tramodern process or product innovations into their opera-tions, thus giving them a competitive edge. The small and medium sized company is promoted as a technology-taker and can claim the services of a technology intermediary organisation.Projects that are eligible for promotion are primarily projects in future technologies designed to boost technology trans-fer in small and medium sized enterprises. The contents of these projects is intended to be the transfer of already developed product or process innovations directly from a technology-giver or with the assistance of a technology in-termediary organisation to one or more technology-takers.The promotion is intended to contribute to meeting the tech-nology needs of the small and medium sized company and to lessen the technical and financial risk associated with the integration of new technologies. Hence, the promotion programme supports small and medium sized enterprises in Saxony as technology-takers, irrespective of the source and form of business organisation of the technology-giver.The following organisations may function as technology-givers:

universities, •extramural research institutions and •extramural research institutes close to industry, as well as•companies.•

Small and medium sized companies can claim the consul-tancy services of a technology intermediary organisation in order to introduce a new technology. Technology interme-diary organisations include technology centres (technology agencies, technology transfer centres, technology startup centres, transfer offices of university and extramural insti-tutions) as well as consultancy firms in Saxony.Investments (purchase of technology from technology-giv-ers) and consultancy services (from technology interme-diary organisations) are eligible for funding, the fundable costs listed below being funded pro rata in the form of a non-repayable grant:

Costs of immaterial investments (purchase of patent •rights, licenses, know-how or non-patentable expertise, customization development),Costs of material investments (purchase of plants, ma-•chines and equipment),Costs of taking up consultancy services (project man-•agement, innovation consultancy and transfer services, technical support and staff training).

PTS in Heidenau can be taken up both as a technology-giver and as a technology intermediary organisation for small and medium sized enterprises in Saxony.

TECHNOLOgy TRANSFER FUNDINg IN SMALL AND MEDIUM SIzED ENTERPRISES IN SAxON

Dr. Frank Miletzky 0049 89 12146 184 [email protected]

contact

The Symposium provides an overview of recent national and international developments in the production of un-coated paper and board. Exchanging views and experience with international colleagues is at the heart of the Sym-posium.

Focus:

Setting the scene•Hot spot - we will look at a burning issue of the paper •industryIntelligent use of resources•Material-saving implementation of product properties•

Increased performance of raw materials and additives•Utilizing the interactions between stock and additves•Economic use of energy and water•Efficient processes•Design and dimensioning of low-loss processes•Economic process control•Data-based process and quality evaluation•Technical visists•With simultaneous translation into English / German•

Registration via mail: [email protected] or PTS homepage: www.ptspaper.de

PTS PAPER SyMPOSIUM, 14TH - 17TH SEPTEMBER 2010 IN MUNICH

26 PTS NewS 03/2009 measuRIng

RAPID ANALySIS OF PAPER COMPONENTS

Easy handling and rapid analysis were accorded top prior-ity during the development of the Paper Analyzer measur-ing system.

In modern paper mills, paper components are even today difficult to determine quickly on the finished product. In most cases, papermaking mills cannot meet personnel and analytical requirements due to a lack of know-how and equipment. The enormous time and cost pressures that prevail in paper mills also conflict with the objectives of comprehensive quality control. The Paper Analyzer was de-veloped for use in the quality control of finished paper in order to meet precisely these needs.A spectroscopic measuring procedure in the near infrared (NIR) is suitable for instantaneously determining paper components in paper such as different fillers and sizing agents, with a minimum of handling and without any sam-ple preparation. This also explains why a NIR diode array

spectrometer was used in the technical design and construc-tion of the Paper Analyzer. This basic configuration was employed to develop a wide range of diverse qualitative and quantitative models. These function as the prerequisites for ultimately being able to corroborate findings regarding the lignin, sizing agent or filler content of the papers tested. The hardware and user interface of the Paper Analyzer are shown in Figures 1 and 2 below.The hardware has been adapted to the respective require-ments; the software can be used for flexible applications and was developed in a co-operative partnership. The inter-action of the hardware and software has already undergone comprehensive testing for one particular application. This particular case involved determining the content of stickies (micro stickies).During the papermaking process, stickies cause serious problems in the form of deposits in stock preparation and in the paper machine itself. Not only is it important to

Fig. 2: Paper Analyzer user interface

Fig. 1: Paper Analyzer hardware

27PTS NewS 03/2009 measuRIng

eliminate these stickies by discharging them, simultaneous process control to evaluate the stickie load is absolutely in-dispensible. The Paper Analyzer lends itself to rapid analy-sis after successful calibration. The figure below shows the results obtained in two separate cases.In addition to using the Paper Analyzer for stickies deter-mination, additional applications are conceivable, e.g. the evaluation of paper two-sidedness or the quality evaluation of pulps in linerboard or in finished packaging (corrugated board), among other things. The Paper Analyzer is not only suitable for laboratory-scale use with finished paper directly at the paper mill, but can be used in principle for any pulp samples obtained from a large number of different produc-tion stages. The preconditions for successfully using the Pa-per Analyzer is that the samples be not too moist and that the corresponding NIR models be available. The Paper Ana-lyzer was developed within the scope of a research project concluded this past summer.

Reference

NIR

Extr

act c

onte

nt in

%

Samples1 2 3 4 5 6 7 8 9 10

6

5

4

3

2

1

0

Reference NIR

Extr

act c

onte

nt in

%

Samples1 2 3 4 5 6 7 8 9 10 11

6

5

4

3

2

1

0

Fig 3: Comparison of the reference and predicted extract contents for stickies determination

Petra Behnsen 0049 3529 551 685 [email protected]

contact

FURTHER DEVELOPMENT OF DOMAS: VERSION 3 .0 AVAILABLE IN DECEMBER

The constant increase of DOMAS user community has turned DOMAS software into a semi standard in the paper industry, especially for the measurement of dirt specks and stickies. In view of this promising trend, PTS will continue to intensify its investments in further developing the DO-MAS system. Version 3.0, which is expected at the end of the year, promises to be a “quantum leap” in scanner cali-bration, among other aspects.As a result of comprehensive comparative tests, the Epson Perfection V750 flat-bed scanner will be integrated into the new DOMAS version in such a way that the comparability of the systems will be greatly improved. Possible deviation of the high-quality scanners will be determined at PTS by extremely accurate quality control testing. Any deviations found will be compensated for by incorporating correction parameters. Newly developed software for scanning the DOMAS images into the system will compensate for device-specific deviations. Bundled evaluation modules can proceed from a device-independent reproduction of the samples.This will allow us to react to future developments on the scanner market. In addition, it also makes it possible for this procedure to recalibrate the DOMAS system after a lamp has been changed or after the scanner has been repaired without

having to modify the value levels in the application modules. PTS will offer readjustment and regular measurement checks as a service to its customers. This of course applies not only to the dirt speck or stickie measurement modules, but also for all other DOMAS modules. Initial tests conducted at PTS using several different devices were so successful that the new system can now go into series production.PTS is planning a DOMAS customer seminar next year, that will focus on the exchange of experience and information as well as future developments currently in the pipeline. You may suggest any topics that interest you even at this early date by sending your suggestions to [email protected]. Help PTS co-design the customer seminar.

Jörg Hempel 0049 3529 551 659 [email protected]

contact


DyNAMIC DIFFERENTIAL SCANNINg CALORIMETRy IMPROVES FIBRE AND PAPER ANALySES With its new heat-flux differential scanning calorimeter, PTS can contribute greatly to assessing the interactions of fibre and cellulose products with water and their effects on drying. Moreover, the method can be used for quality con-trol in plastics production and processing.

The DCS (differential scanning calorimeter) system of the company Mettler-Toledo covers a temperature range from -70°C to 600°C. Its measuring principle is this: a sensor measures the heat flux of a sample compared to a reference, determining the heat flux difference during heating or cool-ing caused by the heat absorbed or lost by the sample. This heat absorption or loss results, among other, from thermal effects like

melting, •crystallizing, •phase transition or•chemical reactions. •

Analyses can be performed with just a few milligrams of sample material. Chemical reactions can be monitored in both inert-gas atmosphere (nitrogen) and air. Depending on the temperature sequence selected, the device records ma-terial-characteristic peaks and graphs which can be attrib-uted to chemical and structural properties of the sample.The measuring system is also an important new tool for PTS research. It is being used in the IGF research project 15707 titled ”Cellulose micro-fibrils“ and sponsored by the Ger-man Federal Ministry of Economics and Labour. The project aims to develop a method for identifying differently bound forms of water in fine-particle cellulose products. These products have already been marketed as “Nanocellulose“ products or are currently being tested .

Developments are based on the chemical-physical interac-tions of cellulose and hydrophilic fibre groups with water molecules. These interactions change the physical behav-iour of water molecules in the pore systems of fibres, no-ticeable by the decrease in melting temperature (freezing point reduction) of water. If a fibre contains enough water, the latter is present in three different states. When dewa-tering and drying swollen pulps step by step, the free and bound but still freezing water is released first. The remain-ing mass share of bound but non-freezing water amounts to approx. 20-30 %. Its interactions with fibres are so strong that it won’t freeze even at -70°C. The very large accessible surface of nanocelluloses suggests changes which can influ-ence the processing and converting properties of cellulose products. DSC studies will therefore contribute significantly to the assessment of fibre and cellulose product interactions with water and of their resulting influences on drying.

DSC measuring system at PTS laboratory

-12

-10

-8

-6

-4

-2

0

-8 -7 -6 -5 -4 -3 -2 -1 0 1 2 3 4 5 6

Temperature / °C

Enth

alpy

of m

elti

ng (e

xo^)

/ m

W

humid pulpWater

Melting curve of deionized water and water contained in a pulp. The deionized water starts to melt at 0 °C. The water bound in fibre walls melts already at -4 °C.

29PTS NewS 03/2009 measuRIng

Quality control of “plastics“Thermal analyses using the DSC system are classic elements of quality control in plastics production and processing. The monomer and polymer constituents of plastics have differ-ent physical/chemical properties exhibiting specific en-thalpy changes during heating and cooling. This makes it possible to identify the exact composition of polymers and resins as well as stresses in these materials caused by insuf-ficient heat supply during curing. Paper converters can use this method to determine the softening/melting and solidification properties of polymer components in paper and composites as well as products made from them. Possible applications include characteri-sations of heat sealing properties of plastic films, and of the softening and solidification properties of adhesive materi-als in package production. Another conceivable application area is the production of photographic and printing papers laminated with LDPE, for example. The DCS system enables PTS to develop further methods in future projects in order to increase its service offers in the field of quality control.

Tiemo Arndt 0049 3529 551 643 [email protected]

Irene Pollex 0049 3529 551 611 [email protected]

contact

Complaints may prove to be an excellent means of iden-tifying optimisation potential in your firm. They are an important pillar in communicating with customers and in promoting the company’s own improvement process. Every complaint means customer communication. Very often, complaints are actually optimisation wishes on the part of the customer for already existing products and thus important indicators of product improvements.In its capacity as an independent, impartial institution, PTS is especially well suited to providing solutions in this particularly sensitive area that take the interests of all partners involved into consideration, whilst nonethe-less remaining affordable. Our know-how ranges from an excellent error analysis of product complaints to an in-vestigation of possible causes. It even includes working out product and process innovations. Our experts will be pleased to provide support in evaluating quality-relevant data, in working together with an 8D problem solving team and, on request, can even moderate a workshop on brainstorming and cause analysis.We develop action plans to avert future complaints and strengthen the competitive edge of your company. In con-crete terms, this means working out proposals and solu-tions designed to eliminate the causes identified, e.g. opti-mising equipment or conducting laboratory- or pilot-scale trials to further improve product properties. If desired, PTS

can also monitor and supervise the action plan that has been suggested (materials testing upon arrival, etc.).PTS’ broad line of services ranges from modern laborato-ries featuring physical paper testing, chemical and instru-mental analysis (SEM, NIR and FTIR spectroscopy, etc.), pilot plants and company-specific in-house seminars and consulting and can be integrated into an overall solution strategy.Making selective use of PTS know-how across the entire paper value chain allows you to supplement your know-how by adding the expertise of PTS experts. This puts you in a position to mitigate insufficient capacity with a view to improving both your products and your production processes. And should a dispute become inevitable – the high level of competence and strict impartiality of PTS ex-perts is also recognised at court.

PTS KNOW-HOW LENDS SUPPORT TO COMPLAINT MANAgEMENT

Dr. Thomas Schönherr 0049 3529 551 613 [email protected]

contact


CASE STUDy: FORMATION MEASUREMENT USINg A PROCEMEx CAMERA

Within the framework of research project IW 070117, PTS formulated and submitted a standardisation proposal for evaluating online formation. The proposal describes the hardware requirements and the basic algorithmic approach used when analysing formation (refer to Research Report for further details).

An online camera system manufactured by Procemex is cur-rently being used to determine whether or not this concept can be implemented in practice. In this process, online im-ages are taken in a paper machine and subsequently evalu-ated by the PTS software module. The results show that the imaging parameters that were chosen do in fact make it possible to analyse formation.PROCEMEX is a leading supplier of broke analysis and web monitoring systems for the papermaking and printing sec-tor on the European and Asian markets. In the coming fu-ture, formation analysis will constitute an essential part of the web monitoring system based on a high-resolution flex camera developed by Procemex.The hardware employed during practical testing consisted of a Procemex-Flex digital camera with 1.3 mill. pixels (1280x1024 pixels) and a Procemex-FlexFlash light source that drives 90 LEDs in flash mode for illumination.A pixel size of approx. 70 µm per pixel was chosen for ini-tial tests. The exposure times were varied between 10 and 40 µs and must be understood as a compromise. The longer the exposure time, the higher the contrast of the paper im-ages. In online operation, however, the paper web will con-tinue to move of course. This causes blurry images when exposure times are long. The parameters selected in these tests, on the other hand, make it possible to obtain sharp images that can then be analysed.Greater pixel sizes constitute the first optimisation option in the case of high-speed paper machines. As a reference for comparison purposes: on a laboratory scale, pixel sizes ranging from 120 – 250 µm are normally chosen for forma-tion studies.The images were evaluated using the algorithms described in the standardisation proposal. In particular, a software module developed by PTS was employed. Production-re-lated changes were found in the contrast and cloudiness parameters. There were only slight variations in these pa-rameters as long as the paper machine settings remained stable. Low values were always registered for orientation, i.e. the paper did not show any prevailing orientation, either MD or CD.The software and hardware produced stable results during the entire trial phase so that testing was completed success-fully. In light of these results, PTS will be offering camera-based formation analysis services in other paper mills in future.Further information: www.procemex.de.

Procemex measuring system for online formation analysis

Björn Zimmermann 0049 3529 551 687 [email protected]

contact

31PTS NewS 03/2009 Training

14th PtS CtP Deinking SymPoSium in muniCh

The next PTS CTP Deinking Symposium will be held in Mu-nich from 27 - 29 April 2010. Chaired by Ms Dr. Elisabeth Hanecker and Mr Dr. Bruno Carré, the event will be or-ganized jointly by PTS and the Centre Technique du Papier (CTP) for the seventh time.

The industry needs new technologies and processes to re-spond to the growing need for recycling, increasing use of deinked pulps, tenuous supply situation of recovered paper, and to resolve current issues of recovered paper sorting and quality control as well as water use. Innovative develop-ments in printing technology and chemical additive use for paper converting are posing extra challenges to recycling today. Rising energy and disposal costs force all partners of the value chain to improve existing recycling processes in a cost-effective way. The Deinking Symposium will present possible solutions to these challenges. Goal is the optimized treatment and use of recovered paper throughout the value chain – from paper production, converting and printing to the collection, sort-ing and shipment of used paper. This is our only chance to succeed in global competition and the dynamic markets of the future. Subject areas addressed by the conference:Markets and trends Recovered paper market, European directives and framework conditions, collection and sorting systems, paper cycles and limits of recycling, value chain paper - print.

Deinking technologies and energy-efficient processesInk removal, chemical use, new ways of separating stick-ies and unwanted components, plant concepts and design, field reports, measuring methods and quality control, simu-lation-aided optimization.Printing processes and future prospects – effects on deinking properties Developments in offset, gravure, flexographic and digital printing techniques.Non-paper components and tacky contaminants Developments in adhesive and adhesive bonding technology, effects on the recycling properties of graphic papers.Environmental issues and future prospects of paper recycling and deinkingEcological issues, bio-refinery, improvements in water, en-ergy and waste management technology

www.Deinking-SymPoSium.Com

international SCientifiC SymPoSium on aPPlieD interfaCe ChemiStry

PTS is organising the "International Scientific Symposium on Applied Interface Chemistry" scheduled on 9 - 10 Febru-ary 2010. The Symposium regularly takes place once every four to five years in Munich.

This international English-language congress showcases current results and new advances in the fields of research and development. The principal focus will be the interface phenomena involved in papermaking. What mechanisms determine the interface and colloidal-chemical interactions between fibres, additives, contaminants and equipment sur-faces? How can the reactions be described and predicted? How can this knowledge be employed to help prevent de-posits and machine failures, to promote process efficiency and to safeguard and enhance paper quality?The papers and keynote lectures will comprise the latest results relating, among other things, to working with con-taminants, to understanding the ins and outs of ASA sizing, to using new bio additives, new analytical and monitoring methods in stock preparation, to the selective condition-ing of machine clothing and the covalent upgrading of the paper surface. At the same time, the programme is also scientifically underpinned academically and focuses on the practical

benefits, particularly for papermakers in their work. The Symposium has as its foremost goal the building of bridges between these two opposing poles. When seen in this light, engineers as well as researchers and developers will be able to take new seminal ideas home with them.Well known industry experts and an audience of competent, highly interested specialists will give excellent opportuni-ties to exchange experiences. We are awaiting developers from R&D and technology in the fields of paper production, chemical additives, microbiocides, measuring equipment, automation, and machinery as well as researchers. They all will present most recent knowledge in scientific and applied research - an exciting event you shouldn`t miss!

www.interfaCe-ChemiStry.Com

Dr. Wolfram Dietz 0049 89 12146 279 [email protected]

Contact

Dr. Elisabeth Hanecker 0049 89 12146 495 [email protected]

Contact

www.ptspaper.dePapiertechnische StiftungPTS in Munich: Hess-Strasse 134 · DE-80797 Munich · Phone +49 (0)89-12146-0 · Fax +49 (0)89-12146-36 PTS in Heidenau: Pirnaer Strasse 37 · DE-01809 Heidenau · Phone +49 (0)3529-551-60 · Fax +49 (0)3529-551-899


· 2017. 8. 16. · 03/09 x perspectives of biorefinery concepts in the paper industry x ozone and...

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