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We are provided countless products from the forest industry and has been through many years. Paper, paper board, packaging materials and furniture to mention a few. A special type of paper used in food packaging for example, is greaseproof paper. Many producers of greaseproof papers use the toxic and harmful group of chemicals called per- and polyfluorinated alkyl substances (PFAS) in coating since they possess grease resistance. Nordic Paper is a manufacturer of iamKraft® kraft paper and greaseproof paper with over a hundred years of experience without the use of PFAS. Without PFAS, they instead rely on excess refining to form a very dense paper. Nordic Paper has decided to introduce the addition of eucalyptus fibers to the softwood sulfate pulp to enhance the formation of the paper. This study aims to investigate the effects of ~20% addition of eucalyptus fibers to softwood sulfate pulp in regard to refiner energy expended, air permeance (as a measure of grease resistance) and formation. Laboratory work has been done on hand made sheets with a vacuum suction box in laboratory scale. Eight different pulps (four with addition of eucalyptus), provided from Nordic Paper Seffle AB, Säffle, with different refining degree was used in this study. The vacuum pressure used was 20 kPa through all tests, with dwell times 0, 1, 2.5, 5, 10, and 20 ms on sheets with a grammage of 50 g/m2. The study has shown that the pulp with ~20% addition of eucalyptus achieved 86°SR with only 82% expended energy relative to the softwood pulp, which had a refining degree of 87°SR. This small difference in refining degree led to a similar development in dewatering after 20 ms dwell time and 20 kPa, where the softwood pulp achieved a dryness of 9.2% and the pulp with addition of eucalyptus achieved 9.0% dryness. The formation of the softwood pulp was worse, which was the reason for the implementation of addition of eucalyptus. The air permeance on the other hand was not improved by the eucalyptu, Vi tillhandahåller otaliga produkter från skogsindustrin och har gjort i många år. Papper, kartong, förpackningsmaterial och möbler för att nämna några. En speciell typ av papper som används i till exempel livsmedelsförpackningar är fettresistent papper. Många tillverkare av dessa papper använder den giftiga och skadliga gruppen av kemikalier som kallas per- och polyfluorerade alkylämnen (PFAS) i beläggning eftersom de har fettbeständiga egenskaper. Nordic Paper är en tillverkare av iamKraft® kraftpapper och ”greaseproofpapper” med över hundra års erfarenhet utan användning av PFAS. Utan PFAS förlitar de sig istället på extra malning av fibrer för att bilda ett mycket tätt papper. Nordic Paper har beslutat att införa tillsats av eukalyptusfibrer till sulfatmassa av barrved för att förbättra formationen på papperet. Denna studie syftar till att undersöka effekterna av ~20 % tillsats av eukalyptusfibrer till barrsvedssulfatmassan med avseende på förbrukad malningsenergi, luftpermeans (som ett mått på fettbeständighet) och formation. Laborationer har utförts på handgjorda ark med vakuumsuglåda i laboratorieskala. Åtta olika massor (fyra med tillsats av eukalyptus), tillhandahållna från Nordic Paper Seffle AB, Säffle, med olika malningsgrad användes i denna studie. Vakuumtrycket som användes var 20 kPa genom alla tester, med uppehållstider 0, 1, 2.5, 5, 10 och 20 ms på ark med en ytvikt på 50 g/m2. Studien har visat att massan med ~20% tillsats av eukalyptus uppnådde 86°SR med endast 82% förbrukad energi i förhållande till sulfatmassan, som hade en malningsgrad på 87°SR. Denna lilla skillnad i malningsgrad ledde till en liknande utveckling i avvattning efter 20 ms uppehållstid och 20 kPa, där sulfatmassan uppnådde en torrhalt på 9.2% och massan med tillsats av eukalyptus uppnådde 9.0% torrhalt. Formationen på sulfatmassan var sämre, vilket var anledningen till genomförandet av tillsats av eukalyptus. Luftpermeansen å andra sidan förbättrades inte av eukalyptusen, men me

Vacuum dewatering of paper is a heavily energy expensive process, even more so for greaseproof paper, which is one of the main products at Nordic Paper Seffle AB. Due to this being such an energy demanding process, improvements in the vacuum dewatering could save massive amounts of energy. The focus of this thesis is to investigate the effect of a triple vacuum suction box on the dewatering rate of greaseproof paper, using a tried and tested method of simulative triple vacuum suction box at a laboratory scale, with the difference of simulating a quadruple vacuum suction box, and how the grammage of the paper sheet affected this, using unbleached sulphate pulp consisting of soft wood with an addition of 20 % eucalyptus fibers. The results were as expected, showing the expected dryness curve behavior of diminishing returns of the dryness to dwell time ratio, and the method showed valid for improving the energy efficiency compared to a single vacuum suction box, in terms of both expended energy, and yielded dryness. The grammage had a significant effect on the dewatering, with the heavier paper at 100 gsm showing the need of higher dwell times and increased levels of vacuum pressure than the lighter paper at 50 gsm. An addition of a triple vacuum suction box could possibly replace multiple high vacuum suction boxes, leading to even greater savings. Further testing would be required for optimization of the vacuum levels and dwell times for the 100 gsm paper sheet, in order to reach the same dryness as the 50 gsm paper sheet., Vakuumavvattning av papper är en mycket energikrävande process, ännu mer för greaseproofpapper, som är en av huvudprodukterna hos Nordic Paper Seffle AB. Eftersom detta är en så energikrävande process kan förbättringar av vakuumavvattningen spara enorma mängder energi. Fokus för denna avhandling är att undersöka effekten av en trippelvakuumsuglåda på avvattningseffektiviteten av greaseproofpapper, med hjälp av en beprövad metod för simulativ trippelvakuumsuglåda i laboratorieskala, med skillnaden att simulera en fyrdubbelvakuumsuglåda, och hur ytvikten på pappersarket påverkar detta; med oblekt sulfatmassa bestående av långfiber med tillsats av 20 % eukalyptusfibrer. Resultaten var som förväntat och visade den förväntade torrhaltskurvans beteende av avtagande förbättring av torrhalten, och metoden visade sig vara giltig för att förbättra energieffektiviteten jämfört med en enda vakuumsuglåda, både vad gäller förbrukad energi och torrhalt. Ytvikten hade en stor effekt på avvattningen, där det tyngre papperet på 100 gsm visade behov av längre uppehållstider och ökade nivåer av vakuumtryck än det lättare papperet vid 50 gsm. Ett tillägg av en trippelvakuumsuglåda kan troligen ersätta flera högvakuumsugslådor, vilket leder till ännu större besparingar. Ytterligare tester skulle krävas för optimering av vakuumnivåerna och uppehållstiderna för 100 gsm pappersarket, för att nå samma torrhet som 50 gsm pappersarket.

Tridecafluorononanoic acid (TFNA), a C6-fluorinated carboxylic acid, was esterified with cellulose at different molar ratios (0:1, 1:1, 2:1, and 3:1) in a trifluoroacetic acid (TFA):trifluoroacetic anhydride (TFAA):CHCl3 (2:1:1, v:v:v) solvent mixture. Free-standing films were obtained for all formulations and are presented as alternatives to composites and blends of paper with fluorinated molecules. Mechanical properties were investigated by tensile tests, and a plasticizer effect of fluorinated chains was observed. Interestingly, the wettability of these new cellulose derivatives was similar or even better than other common cellulose derivatives and fluorinated polymers employed in food packaging. Hydrodynamic properties were also improved by addition of TFNA, resulting in materials with water vapor permeability values comparable to other cellulose-based food packaging materials. In addition, films with the higher amounts of TFNA showed the required oil resistance for papers used in food packaging applications, as determined by the Kit Test. Finally, the biodegradation of these C6-fluorinated cellulose esters, assessed by biological oxygen demand (BOD) in seawater, was higher than typical bio-based polymers used in food packaging. The bioplastic synthesized at a molar ratio 1:1 (TFNA:cellulose) showed excellent performances in terms of greaseproof, hydrophobicity, ductility, and biodegradability, representing a sustainable alternative to typical plastics used in food packaging.

A full-scale mill trial surveyed the energy required to produce greaseproof paper. The furnishes studied were a 100% sulfite pulp and a 50/50 sulfite/sulfate pulp, refined to two freeness levels. The papers produced were then calendered at two line-loads using a soft-nip laboratory calender and tested with respect to air permeability, water vapor transmission rate, grease resistance, tear strength, and tensile strength. The least energy-demanding (beating + drying) process was that used to produce the paper from 100% sulfite pulp of low freeness. This paper exhibited approximately the same water vapor transmission rate and grease resistance as the paper made from high freeness 100% sulfite pulp. The papers produced from 50/50 sulfite/sulfate furnish exhibited poorer barrier properties. The mechanical properties of all the papers produced satisfied the specifications for standard greaseproof paper. Beating improved the barrier properties, but required additional energy. Results showed that the same or better barrier properties can be achieved with calendering or surface coating, with lower energy input. We also found that the furnish composition and beating and the calendering affected air permeability in different ways. The former affected both the pore volume fraction and the pore dimensions, while the latter mainly affected the pore volume fraction, Barrier coatings for greaseproof paper