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Made available in DSpace on 2016-02-05T18:29:12Z (GMT). No. of bitstreams: 0 Previous issue date: 2015-07-28. Added 1 bitstream(s) on 2016-02-05T18:33:19Z : No. of bitstreams: 1 000855477_20170728.pdf: 502059 bytes, checksum: 440902edaf001dd47124defa89925e9d (MD5) Bitstreams deleted on 2017-07-28T12:36:18Z: 000855477_20170728.pdf,. Added 1 bitstream(s) on 2017-07-28T12:37:11Z : No. of bitstreams: 1 000855477.pdf: 1856121 bytes, checksum: 7c0057c5cca420362cf5ef38fe3ff40a (MD5) Bitstreams deleted on 2017-08-07T14:09:11Z: 000855477.pdf,. Added 1 bitstream(s) on 2017-08-07T14:10:15Z : No. of bitstreams: 1 000855477.pdf: 1856121 bytes, checksum: 7c0057c5cca420362cf5ef38fe3ff40a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os papéis produzidos em sistemas alcalinos apresentam melhores propriedades dos que os produzidos em sistemas ácidos além de possibilitar a utilização de carbonato de cálcio como carga. A presente pesquisa teve como objetivo viabilizar a utilização de breu como agente de colagem interna em meios neutro/alcalinos de produção de papel. Na pesquisa foram realizados três estudos para o desenvolvimento de um novo agente de colagem, sendo o diferencial a esterificação do breu seguida de pré-mixagem com policloreto de alumínio (PAC) em diferentes concentrações. As colas foram avaliadas em papéis formados por polpa industrial branqueada ECF, amido, PAC e cola. As folhas formadas com os aditivos foram avaliadas com relação à eficiência de colagem em linha de cobertura de papel cartão com gramatura de 100 g/m². Também foi realizado um estudo em indústria, através de simulação laboratorial de aplicação na massa da camada de cobertura da máquina de papel da Klabin - Unidade de Monte Alegre. Um segundo estudo teve como objetivo avaliar o desempenho de diferentes sequências de branqueamento de celulose de eucalipto kraft-O2 na colagem interna da camada superficial do cartão de papel. Seis sequências diferentes de branqueamento foram avaliadas, sendo quatro ECF - D(E+P)DD; AHTD(E+P)DD; AHTD(E+P)DP e AHTDEDP - uma ECF-Light - AHTD(PO)D e uma nova sequência ECF - AHTDP. As polpas foram branqueadas para 90 ± 0,5% ISO. Após o branqueamento as polpas foram refinadas até que atingissem 40° Schopper-Riegler (SR°). Depois disso, as folhas (100 g/m²) foram formadas com 10 kg/t de agente de colagem industrial com a adição de 6 kg/t de PAC, em diferentes pH's (7,0;7,5 e 8,0). Os parâmetros de qualidade analisados foram teste de Cobb e Edge Wickings peróxido, lático e água. Os resultados provaram a eficiência da nova cola para os parâmetros avaliados / The papers produced in alkaline systems shows better properties than those produced in acidic systems and enable the use of calcium carbonate as a filler. This research aimed to enable the use of a rosin based product as internal sizing agent in neutral/ alkaline system of papermaking process. Three studies were conducted research for the development of a new sizing agent, the differential being the esterification of rosin then pre-mixing with PAC (polyaluminium chloride) at different concentrations. The sizing agents were evaluated on papers made up of bleached ECF pulp industry, starch, cap and sizing agent. The sheets formed with the additives were evaluated for sizing efficiency (Cobb test, Edge Wickings peroxide, lactic acid and water) in paper coating line of paper card - 100 g/m². It was also conducted a study in industry through laboratory simulation. It's about the application from the sizing agent in the mass of paper machine covering layer #9 Klabin - Monte Alegre Unit. A second study aimed to evaluate the performance of different sequences pulp bleaching kraft-O2 eucalyptus in internal sizing of the surface layer of the paper card. Six different bleaching sequences, being four ECF's - D(E+P)DD; AHTD(E+P)DD; AHTD(E+P)DP; AHTDEDP, an ECF-Light - AHTD(PO)D and a new short bleaching sequence ECF - AHTDP are investigated. The pulps were bleached to 90 ± 0.5% ISO. The pulps were refined in PFI mill and refine the curve was determined by previous tests. The pulps held at 40 ° Schopper-Riegler (° SR). Thereafter, handsheets (100 g / m²) were formed with 10 kg/t industrial sizing agent plus 6 kg/t industrial PAC, at different pH ranges (7.0, 7.5, 8.0). Quality parameters analyzed were Cobb test, Edge Wickings peroxide, lactic acid and water. The results proved the efficiency of the new sizing agent to the parameters evaluated

Orientador: Gustavo Ventorim / Coorientador: José Cláudio Caraschi / Banca: Maria Angélica Martins Costa / Banca: Claudio Angeli Sansigolo / Banca: Dalton Longue Júnior / Banca: Danielle Goveia / Resumo: Os papéis produzidos em sistemas alcalinos apresentam melhores propriedades dos que os produzidos em sistemas ácidos além de possibilitar a utilização de carbonato de cálcio como carga. A presente pesquisa teve como objetivo viabilizar a utilização de breu como agente de colagem interna em meios neutro/alcalinos de produção de papel. Na pesquisa foram realizados três estudos para o desenvolvimento de um novo agente de colagem, sendo o diferencial a esterificação do breu seguida de pré-mixagem com policloreto de alumínio (PAC) em diferentes concentrações. As colas foram avaliadas em papéis formados por polpa industrial branqueada ECF, amido, PAC e cola. As folhas formadas com os aditivos foram avaliadas com relação à eficiência de colagem em linha de cobertura de papel cartão com gramatura de 100 g/m². Também foi realizado um estudo em indústria, através de simulação laboratorial de aplicação na massa da camada de cobertura da máquina de papel da Klabin - Unidade de Monte Alegre. Um segundo estudo teve como objetivo avaliar o desempenho de diferentes sequências de branqueamento de celulose de eucalipto kraft-O2 na colagem interna da camada superficial do cartão de papel. Seis sequências diferentes de branqueamento foram avaliadas, sendo quatro ECF - D(E+P)DD; AHTD(E+P)DD; AHTD(E+P)DP e AHTDEDP - uma ECF-Light - AHTD(PO)D e uma nova sequência ECF - AHTDP. As polpas foram branqueadas para 90 ± 0,5% ISO. Após o branqueamento as polpas foram refinadas até que atingissem 40° Schopper-Riegler (SR°). Depois disso, as folhas (100 g/m²) foram formadas com 10 kg/t de agente de colagem industrial com a adição de 6 kg/t de PAC, em diferentes pH's (7,0;7,5 e 8,0). Os parâmetros de qualidade analisados foram teste de Cobb e Edge Wickings peróxido, lático e água. Os resultados provaram a eficiência da nova cola para os parâmetros avaliados / Abstract: The papers produced in alkaline systems shows better properties than those produced in acidic systems and enable the use of calcium carbonate as a filler. This research aimed to enable the use of a rosin based product as internal sizing agent in neutral/ alkaline system of papermaking process. Three studies were conducted research for the development of a new sizing agent, the differential being the esterification of rosin then pre-mixing with PAC (polyaluminium chloride) at different concentrations. The sizing agents were evaluated on papers made up of bleached ECF pulp industry, starch, cap and sizing agent. The sheets formed with the additives were evaluated for sizing efficiency (Cobb test, Edge Wickings peroxide, lactic acid and water) in paper coating line of paper card - 100 g/m². It was also conducted a study in industry through laboratory simulation. It's about the application from the sizing agent in the mass of paper machine covering layer #9 Klabin - Monte Alegre Unit. A second study aimed to evaluate the performance of different sequences pulp bleaching kraft-O2 eucalyptus in internal sizing of the surface layer of the paper card. Six different bleaching sequences, being four ECF's - D(E+P)DD; AHTD(E+P)DD; AHTD(E+P)DP; AHTDEDP, an ECF-Light - AHTD(PO)D and a new short bleaching sequence ECF - AHTDP are investigated. The pulps were bleached to 90 ± 0.5% ISO. The pulps were refined in PFI mill and refine the curve was determined by previous tests. The pulps held at 40 ° Schopper-Riegler (° SR). Thereafter, handsheets (100 g / m²) were formed with 10 kg/t industrial sizing agent plus 6 kg/t industrial PAC, at different pH ranges (7.0, 7.5, 8.0). Quality parameters analyzed were Cobb test, Edge Wickings peroxide, lactic acid and water. The results proved the efficiency of the new sizing agent to the parameters evaluated / Doutor

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Thesis (MScFor)--University of Stellenbosch, 2007. / ENGLISH ABSTRACT: Unextracted (control) and PHWe Eucalyptus grandis wood chips were pulped at 15% active alkali (AA) and 1% antraquinone (AQ). Another batch of wood chips were then inoculated with fungal co-cultures of Aspergillus flavipes and Pycnoporus sanguineus. FCCi wood chips were incubated for four weeks; one PHWe inoculated experimental treatment was incubated for three weeks. The full pulping cycle (160 min) was used to digest the experimental treatments with the exception of one lot of PHWe wood chips that were pulped for 150 minutes. A further experimental treatment of PHWe wood chips was cooked at a reduced AA charge of 14% and 1% AQ. Analysis of variance (ANOVA) of the data from all the experimental treatments was conducted and the differences within the experimental treatments were determined using Statistica (v7, 1984–2006). The F-value (Fischer distribution) and the p-value as well as a non-parametric test known as the Mann-Whitney procedure was tested at the 95% confidence limit. For a further enhancement of the 95% confidence limit the screened yield data was tested by the Bootstrap method. Scanning electron micrographs clearly demonstrated the changed structure and appearance of the chip cross-sectional area after the different pretreatments. Although the mean average results of all the screened pulp yields showed no significant statistical difference (p> 0.05), differences in screened yield of up to 2.5% were obtained. All the weighted means of the rejects showed a significant difference (p < 0.05). Other pulp properties like shive content, chemical consumption, Kappa number, handsheet brightness and strength tests showed mixed results i.e. rejected or accepted the hypothesis (p> or =or < 0.05). The hypothesis that the combined PHWE and FCCI of wood chips would further increase the pulp yield had to be rejected. It is however anticipated that the combination of PHWE with successive co-culture fungal pretreatment would be very beneficial in obtaining higher pulp yields for fully bleached chemical pulp. Further research would be required to test this assumption. This investigation confirmed the expected beneficial effects of combined PHWE and FCCI pretreatments of wood chips on the strength properties. In addition the combined treatment also improved the initial bonding strength potential of the unbeaten fibres. / AFRIKAANSE OPSOMMING: Onbehandelde en met onder druk, warm water uitgeloogde Eucalyptus grandis houtspaanders is respektiefwelik met 15% aktiewe alkali (AA) en 1% antrakinoon (AQ) verpulp. Hierdie is dan met swamkokulture van Aspergillus flavipes en Pycnoporus sanguineus inokuleer en respektiewelik vir drie en vier weke inkubeer. Onder druk uitgeloogde houtspaanders is ook vir 150 minute verpulp by 15% AA 1% AQ en by ‘n verminderde AA van 14%. Pulpevaluasies is uitgevoer op alle eksperimentele behandelinge. Alle onder druk uitgeloogde en met swamkokultuur inokuleerde houtspaanders het ‘n laer pulpopbrengs, uitskot, skilferinhoud, Kappanommer en ‘n hoër RAA en helderheid opgelewer in vergelyking met die vars houtspaanders. Die vars en warm water uitgeloogde houtspaanders het soortgelyke pulpopbrengs opgelewer. ‘n Variansieanalise (ANOVA) van die data van alle eskperimentele behandelings is uitgevoer gebruikmakende van Statistica (V7, 1984 – 2006). Die F-waarde (Fischer-verspreiding) an die p-waarde so wel as ‘n parametriese toets (Mann-Whitney prosedure) is getoets by ‘n 95% betroubaarheidsgrens. Vir ‘n verdere verhoging van die 95% betroubaarheidsgrens van die pulpopbrengs, is die beskikbare data weer getoets met die Bootstrap-metode. Alle gemiddelde pulpopbrengswaardes het geen beduidende statistiese verkil opgelewer nie (p>0.05), alhoewel verskille van tot 2.5% in pulpopbrengs verkry is. Alle gemiddelde uitskotwaardes het ‘n beduidende verskil getoon (p<0.05). Die ander pulpeienskappe soos skilferinhoud, verbruik aan chemikalieë, Kappagetal, handvel helderheid en sterktewaardes het gemengde resultate opgelewer maw verwerping of aanvaarding van die hipotese p> or =or < 0.05. Die hipotese dat die gekombineerde PHWE en FCCI van die houtspaanders die pulpopbrengs verder sou verhoog moes verwerp word. Daar word egter verwag dat die kombinasie van PHWE met opeenvolgende swamkokultuur behandeling baie voordelig sou wees op die pulpopbrengs van ‘n ten volle gebleikte chemiese pulp. Verdere navorsing is nodig om hierdie veronderstelling te toets. Die ondersoek het die verwagte woordelige effek van die gekombineerde PHWE en FCCI voorbehandelings van die houtspaanders op die papierstrkte-eienskappe bevestig. Bo en behalve dit, het die gekombineerde behandeling ook die aavanklikte bindsterkte potensiaal van die ongeklopte vessels verbeter.