LWC-paperin opasiteetin parantaminen

LWC-syväpainopaperilta vaaditaan hyvän ajettavuuden, kiillon ja sileyden ohella hyvää opasiteettia. Tämä on asettanut haasteita LWC-paperin valmistajille paperin neliömassojen laskiessa. Tässä diplomityössä etsittiin keinoja parantaa kevyiden LWC-syväpainolajien opasiteettia heikentämättä oleellisesti muita tärkeitä paperin ominaisuuksia. Tavoitteena oli nostaa CR48-lajin opasiteetti tavoitearvoon 90 %. Työn kirjallisuusosassa perehdyttiin paperin optisten ominaisuuksien teoriaan sekä raaka-aineisiin ja prosessin osiin, joilla on vaikutusta paperin opasiteettiin. Työn kokeellisessa osassa tutkittiin olemassa olevan aineiston perusteella tekijöitä, joilla uskottiin olevan vaikutusta CR48-lajin opasiteettiin. Tutkimuksen ja kirjallisuuden perusteella ajettiin tehdaskoeajoa, joiden avulla pyrittiin parantamaan paperin opasiteettia. CR48-lajin opasiteettitavoite saavutettiin kolmella eri tavalla. Opasiteettitavoite saavutettiin, kun paperin vaaleus säädettiin tavoitearvoon pigmenttivärin avulla tumman hierteen sijasta. Tällöin väripigmentin määrää päällystyspastassa nostettiin 0,01 osaa ja valkaistun hierteen osuus kokonaishierteen määrästä oli 100 %. Vaaleuden säätö pastavärillä oli käytännössä hidasta ja hankalaa. Opasiteettitavoite saavutettiin myös, kun hierre jauhettiin täysin koeterillä. Koeterillä tapahtuva jauhatus oli rajumpaa ja katkovampaa kuin perinteisillä terillä, joten hienoaineen lisääntyminen ja kuidun lyheneminen paransivat paperin opasiteettia, mutta lujuudet huononivat. Lisäksi tavoiteopasiteetti saavutettiin, kun sellun osuutta vähennettiin 8 %-yksikköä. Lujuuden säilymisen kannalta sellun vähennys oli parempi keino opasiteetin parantamiseksi kuin hierteen jauhaminen koeterillä. Koeajojen perusteella pohjapaperin tuhkapitoisuuden nostolla ja hierteen CSF-luvun alentamisella ei ollut vaikutusta paperin opasiteettiin. Lisäksi 100 %:nen koeterillä jauhettu sahahakehierre antoi paperille huonomman opasiteetin kuin hierre, josta puolet oli jauhettu koeterillä ja raaka-aineesta 25 % oli sahahaketta.

Vannesahalinjan tuotantokapasiteetin kasvattaminen konstruktiota kehittämällä

Tässä tutkimuksessa selvitetään, mitä muutoksia vannesahalinjan koneisiin tulee tehdä, jotta syöttönopeutta voidaan nostaa. Lisäksi työn perusteella on onnistuttu sahaamaan tuotannossa ohuemmalla terärungolla samalla mittatarkkuudella kuin aikaisemmin paksummalla terärungolla. Työssä on kartoitettu kyseessä olevan vannesahalinjan todennäköisimmät pullonkaulat nopeutta nostettaessa. Lisäksi on tarkasteltu mittauksin eräiden kriittisten koneiden käyttäytymistä sahauksen aikana. Mittausten perusteella on tehty ehdotukset tarvittaville konstruktiomuutoksille, jotta sahaus korotetulla nopeudella onnistuu hyvällä mittatarkkuudella. Tutkimuksen aikana on kehitetty mittausjärjestelmä, jolla vannesahan teräpyörien muoto voidaan mitata ja siirtää tietokoneelle myöhempää tarkastelua ja arkistointia varten.

The Impact of Aspen and Alder on the Quality of NHBK

The purpose of this work was to study the effect of aspen and alder on birch cooking and the quality of the pulp produced. Three different birch kraft pulps were studied. As a reference, pure aspen and alder were included. The laboratory trials were done at the UPM Research Centre in Lappeenranta, Finland. The materials used were birch, aspen and alder mill chips that were collected around the area of South-Carelia in Finland. The chips used in the study were pulped using a standard kraft process. The pulps including birch fibres were ECF-bleached at laboratory scale to a target brightness of 85 %. The bleached pulps were beaten at low consistency by a laboratory Voith Sulzer refiner and tested for optical and physical properties. The theoretical part is a study of hardwoods that takes into accounts the differences between birch, aspen and alder. Major sub-areas were fibre and paper-technical properties as well as chemical composition and their influence on the different properties. The pulp properties of birch, aspen and alder found in previous studies were reported. Russian hardwood forest resources were also investigated. The fundamentals of kraft pulping and bleaching were studied at the end of theoretical part. The major effect of replacing birch with aspen and alder was the deterioration (lowering) of tensile and tear strengths. In other words, addition of aspen and alder to a birch furnish reduced strength properties. The reinforcement ability of the tested pulps was the following: 100 % birch > 80 % birch, 20 % aspen > 70 % birch, 20 % aspen, 10 % alder. The second thing noted was that blending of birch together with aspen and alder give better smoothness, optical properties and also formation. It can be concluded, that replacement of birch with alder during cooking by more than 10 % can negatively affect on the paper-technical properties of birch pulp. Mixing pure birch and aspen pulps would be more beneficial when producing printing paper made from chemical pulp.

Tukin mittaus ja optimointi sahalinjassa

Tukin mittaus ennen sahausta ja sahausasetteen optimointi on kehittynyt paljon viimeisen 10 vuoden aikana. Sahauksen kannattavuuden huonontuessa raaka-aineen tehokas hyödyntäminen on muodostunut tärkeäksi osaksi prosessia. Mittalaitteiden tekniikan kehityttyä on ollut mahdollista mitata tukin muoto ja halkaisijat eri kohdista entistä tarkemmin. Sahausasetteen optimoinnilla pyritään raaka-aineen mahdollisimman tehokkaaseen käyttöön eli saamaan mahdollisimman hyvä saanto jokaisesta yksittäisestä sahatusta tukista. Mittaustarkkuus on suoraan kytköksissä sahausasetteen optimointi tuloksen onnistumiseen. Yleisesti tukin mittaus ennen sahausta ja sahausasetteen optimointi tulevat samalta toimittajalta. Työssä tarkasteltiin kahden eri toimittajan tukkimittareita sekä optimoinnin onnistumista sen perusteella. Käytössä oli lasikuituinen mallitukki, jota mitattiin kummankin toimittajan mittareilla. Näin voitiin suoraan vertailla mittauksen ja optimoinnin onnistumista ja verrata sitä optimaalisiin tuloksiin. Työssä käytettiin kandidaatintyössä luomaani toimintamallia tukkimittarin tarkkuuden toteamiseksi. Mittaus- ja optimointivirheistä pystyttiin laskemaan, kuinka paljon tappiota sahalaitokselle aiheutui verrattuna optimaaliseen mittaus- ja optimointitulokseen. Jo pienetkin virheet optimoinnissa ja mittauksessa vaikuttavat sahauksen kannattavuuteen, kun tarkastellaan sahalaitosta jossa sahataan 8000 – 10 000 tukkia yhden työvuoron aikana. Tulosten perusteella mittarit mittaavat hieman virheellisesti, ja kummankin mittarin mittausten perusteella saatiin eri sahausasete optimointitulokseksi. Mittavirheen takia voitiin todeta, että parantamalla mittaustarkkuutta voidaan sahauksen kannattavuutta parantaa.

Second Welland Canal - Book 1, Survey Map 1 - Entrance, Lock 1 and Port Dalhousie

Survey map of the Second Welland Canal created by the Welland Canal Company showing the areas in and around Port Dalhousie and Grantham Township. Identified structures associated with the Canal include Lock 1, Lighthouse, Lighthouse Keeper's House, East and West Piers, Harbour, Waste Weir, Store House, Collector's Office, Collector Assistant Office, Lock Tender's House and the new towing path. Features of the First Welland Canal are noted in red ink and includes the old Harbour, old Lock 1, old towing path and the original bed of the Twelve Mile Creek. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks and businesses are also identified and include streets and roads (ex. Lock Street and Colonel Clark's Cattle Road), Alex Muir's Dry Dock, RandJ Laurie Flouring Mill, R. Laurie and Company Grist Mill, A. Morrison Saw Mill, Johnson's Tavern, a store and a church. Properties and property owners of note are: Concession 1 Lots 21 and 22, John Christie, John Clark, N. Pawling, William Pawling, W. Carter, G.A. Clark, J. Maven, Mrs. Wood, James Drabble and J. Woodall.

Second Welland Canal - Book 1, Survey Map 2 - Lock 1 and Port Dalhousie

Survey map of the Second Welland Canal created by the Welland Canal Company showing the areas in and around Port Dalhousie and Grantham Township. Identified structures associated with the Canal include Lock 1, East and West Piers, Collector's Office, Lock Tender's House and the new towing path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks and businesses are also identified and include streets and roads (ex. Road to St. Catharines, Side Line, Old Road to Port Dalhousie, Road to Niagara), the Welland Railway and its structures (ex. freight sheds, wood shed, raised platform, elevator, cranes, water tank, turn table, and passenger station), G. A. Clark's Wood Yard, Clark's Wood Office, Alex Muir's Dry Dock, Donald, Andrews and Ross' Dry Dock, RandJ Laurie Flouring Mill, R. Laurie and Company Grist Mill and A. Morrison Saw Mill. A New Road to St. Catharines is featured in red ink. Properties and property owners of note are: Concession 1 Lots 19, 20 and 21, John Christie, and John Clark.

Second Welland Canal - Book 1, Survey Map 6 - Through Grantham and Louth Townships

Survey map of the Second Welland Canal created by the Welland Canal Company showing the area between the Townships of Grantham and Louth. Identified structures associated with the Canal include the floating tow path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Features of the First Welland Canal are noted in red ink and include the old towing path, and the original bed of the Twelve Mile Creek. Local area landmarks are also identified and include streets and roads (ex. New Road, 1st Concession Road, and an unnamed road in the top right corner), an unnamed bridge along New Road, J. Martindale's House, an Old Saw Mill, Richardsons Creek, Georges Point, and an oak tree at Georges Point. Properties and property owners of note are: Concession 2 Lot 23 and Concession 3 Lot 23 in the Grantham Township, Concession 2 Lots 1 and 2, and Concession 3 Lots 1 and 2 in the Louth Township, Peter Weaver, J. Martindale, and John Bonner. A property belonging to the Board of Works is outlined in red at Georges Point.

Second Welland Canal - Book 1, Survey Map 14 - St. Catharines and Lock 5

Survey map of the Second Welland Canal created by the Welland Canal Company showing the Canal along the eastern edge of the Town of St. Catharines. Identified structures associated with the Canal include Lock 5 and the towing path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks are also identified and include bridges, streets, and roads (ex. Queenston Street, St. Catharines Macdamized Road and Suspension Bridge), a Pond, a number of unnamed bridges, Stinson's Distillery, and R. Collier's Saw Mill. Properties and property owners of note are: Concession 6 Lots 14 and 15, R. Collier, W. Gillespie, Orson Phelps, W. Chase, M. Bryant, John Soper, Winsor Chace, John Berryman, John Boyle, J. Madigan, B. F. Reynolds, W. Smaill, F. Stinson, G. Ward and Mrs. Soper.

Second Welland Canal - Book 2, Survey Map 1 - Locks 5, 6 and 7 in Grantham

Survey map of the Second Welland Canal created by the Welland Canal Company showing the Grantham Township just southeast of the Town of St. Catharines. Identified structures associated with the Canal include Locks 5, 6, and 7, two Lock House Lots, Small Lock House, waste weir, and the towing path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks are also identified and include roads (ex. Road to Thorold), Dicks Creek, R. Collier's Saw Mill, a gate yard, paper mill, grist mill, store house, and a barn. Properties and property owners of note are: Concession 7 Lots 13, 14, and 15, R. Collier, Orson Phelps, and a Mill Lot leased to Richard Collier.

Second Welland Canal - Book 2, Survey Map 3 - Locks 8, 9 and 10 in Grantham

Survey map of the Second Welland Canal created by the Welland Canal Company showing the Grantham Township between the Town of St. Catharines and Merritton. Identified structures associated with the Canal include Locks 8, 9, and 10, waste weirs, the towing path, and several floating bridges. The surveyors' measurements and notes can be seen in red and black ink and pencil. Several stones and tree stumps likely used in the measurements are identified on the map. Local area landmarks are also identified and include streets and roads(ex. Macadamized Road to Thorold), J. Hamilton's Hotel, a school house, McCoy's Farm House, Bradley's House, O. Phelps Saw Mill, Disher and Hait's Woolen Mill, Centreville Mills, a bridge, several barns, and a number of structures (possibly houses, cabins, or shops) belonging to: P. McCoy, E. McLachlan, T. Wilson, W. Wilson, M. Bradley, S. Bradley, P. Boyle, J. Bradley, E. Grant, and W. Church. Lock 12 and 15 of the original canal are also identified. Properties and property owners of note are: Concession 8 Lots 12, 13 and 14, O. J. Phelps, P. McCoy, A. Bradley, C. Bradley, T. Reed, O. Clifford, J. Bradley, W. C. Loan Company, Duffin, and T. Towers Mill Lot.

Second Welland Canal - Book 2, Survey Map 6 - Locks 19, 20, 21 and 22 in Grantham

Survey map of the Second Welland Canal created by the Welland Canal Company showing south Merritton along the boundary between the Grantham and Thorold Townships. Identified structures associated with the Canal include Locks 19, 20, 21, and 22, Lock Tenders House, and the towing path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks are also identified and include streets and roads (ex. Pine Street and Macadamized Road), J. Brown Cement Mill, W. B. Hendershot Saw Mill, W. Parnall Spoke and Sash Factory, W. Beatty Saw Mill, W. Beatty Tannery, a number of structures (possibly houses) belonging to: Mrs. Aikins, J. Battle, and E. Keefer, and a foundry, smithy, and machine shop (all of which possible belonged to J. Dobbie). Properties and property owners of note are: Concession 10 Lots 9 and 10, W. C. Loan Company, P.H. Ball, and J. Keefer. Two small properties belonging to W. B. Hendershot and W. Beatty exist and are outlined in red. A half acre property reserved for a lock lot exists and is outlined in blue. An additional property reserved for a quarry is also identified, but not outlined.

Second Welland Canal - Book 2, Survey Map 7 - Locks 23, 24 and 25 in Thorold

Survey map of the Second Welland Canal created by the Welland Canal Company showing the canal as it passes through the Village of Thorold. Identified structures associated with the Canal include Locks 23, 24, and 25, a Guard Gate, Lock House Lot, the Little Deep Cut, and the towing path. The surveyors' measurements and notes can be seen in red and black ink and pencil. Local area landmarks are also identified and include streets and roads(ex. Pine Street and Front Street), a basin, a mill race, McPherson and Wier's Grist Mill, Brown and Ross Flouring Mill, R. James Store, J. Brown Cement Mill, W. B. Hendershots Store, Keefers Mill, J. Woodward Grist Mill, Brierly McWhirter and Co. Cotton Mill, E. W. Stephenson Tavern, a factory and a saw mill on W. H. Ward's property, a flouring mill, engine house, a store house, several barns, J. Brown's Wharf, and a number of structures belonging to: Jenkinson, Mrs. McCarty, John Clay, M. McDonnah, Mrs. Donahoc, W. B. Hendershott, Mrs. Pawling, and Christy. Properties and property owners of note are: Lots 8, 9, 16, and 17, W. H. Ward, J. Keefer, G. Keefer Jr., G. Keefer Sr., Dr. Rolls, W. Hendershott, Cleveland, Lucy, and R. Leeper.