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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Simulação de unidade de recuperação química do processo de polpação kraft visando a obtenção de metanol celulósico / Simulation of a chemical recovery unit of kraft pulping to obtain the cellulosic methanol

Stape, Glauco Joubert 10 April 2017 (has links)
O aumento da conscientização ecológica, observado nos últimos anos, levou às indústrias investirem em alguns sistemas de produção tecnologicamente menos impactantes ao meio ambiente, como é o caso das biorrefinarias. No setor de celulose e papel as indústrias podem ser consideradas como biorrefinarias pois produzem bioenergia e bioprodutos a partir da utilização da biomassa, tais como energia elétrica e polpa celulósica. No processo de polpação kraft, obtém-se o licor negro o qual contém compostos orgânicos e inorgânicos provenientes da matéria prima e dos reagentes químicos e aditivos utilizados no processo. Com isso, o licor negro contém além da lignina dissolvida da madeira, alguns subprodutos formados em reações específicas e que podem ser recuperados, destacando-se entre esses o metanol, o qual pode chegar a compor 1% do licor negro. O metanol celulósico extraído na etapa de tratamento de condensado contaminado contém diversos compostos noviços ao meio ambiente e por este motivo o metanol celulósico é utilizado como combustível, sendo incinerado para geração de energia e para redução dos contaminantes a formas menos nocivas ao meio ambiente. Assim, obter o metanol celulósico significa purificá-lo para que possa ser aplicado para outros fins mais nobre, como por exemplo, aplicado como reagente nas indústrias químicas. Com isso, o presente estudo teve por objetivo avaliar o potencial de operação de uma unidade de recuperação e de purificação de metanol celulósico acoplado a uma moderna unidade de produção de polpa celulósica. Para isso, foram realizadas visitas técnicas à unidade industrial e efetuada uma ampla revisão bibliográfica do processo de evaporação de licor negro e de formação dos compostos presentes no metanol celulósico de forma a definir as condições e métodos de modelagem e simulação mais apropriados para o desenvolvimento desta dissertação. O estudo foi divido em duas etapas, sendo que a primeira consistiu na utilização do simulador comercial WinGEMS® para construção de um modelo computacional de uma unidade de evaporação de licor negro, o qual mostrou-se adequado para a determinada aplicação através de validações comparativas entre os resultados da simulação com valores reais de operação. Na sequência, desenvolveu-se um modelo computacional para o planejamento de uma unidade de obtenção e purificação de metanol celulósico via software Aspen Plus® sendo acoplado ao modelo anterior. Em síntese, a metodologia aplicada mostrou-se satisfatória para o presente estudo sendo possível simular com propriedade uma unidade de evaporação de licor negro e avaliar o impacto industrial de se acoplar uma unidade de purificação de metanol celulósico a indústria celulósica, no que tange a dimensionamentos de equipamentos, quantificação dos insumos e eficiência de purificação de metanol celulósico. / The increase in ecological awareness observed in recent years has led industries to invest in some production systems technologically less harmful to the environment, such as biorefineries. The industries form the pulp and paper sector, can be considered as biorefineries because they produce bioenergy and bioproducts from the use of biomassa, such as electric power and cellulosic pulp. In the kraft pulping process, the black liquor is obtained, wich contains organic and inorganic compounds from the raw material and from the chemicals reagents and additives used in the process. Black liquor contains, in addition to the dissolved lignin of the wood, some by-products formed in specific reactions and that can be recovered, among them methanol, which can make up 1% of the black liquor. The cellulosic methanol extracted in the treatment stage of contaminated condensate contains several compounds that are harmful to the environment and for this reason the cellulosic methanol is used as fuel, being incinerated for energy generation and for the reduction of contaminants to forms less harmful to the environment. Thus, obtaining the cellulosic methanol means purifying it so that it can be applied to other, more noble purposes, for example, as a reagent in the chemical industry. The aim of this study was to evaluate the potential of a cellulosic methanol recovery and purification unit coupled to a modern cellulosic pulp production unit. Technical visits were made to the industrial unit and a vast bibliographical review of the process of evaporation of black liquor and formation of the compounds present in the cellulosic methanol was carried out in order to define the conditions and the most appropriate modeling and simulation methods for the development of this dissertation. The study was divided in two stages, the first one consisted of the use of the WinGEMS® commercial simulator to construct a computational model of a black liquor evaporation unit, which proved to be suitable for the given application through comparative validations between simulation results with actual operating values. In the sequence, a computational model was developed for the planning of a cellulosic methanol purification and purification unit using Aspen Plus® software being coupled to the previous model. In summary, the applied methodology proved to be satisfactory for the present study, being it possible to properly simulate a black liquor evaporation unit and to evaluate the industrial impact of coupling a cellulosic methanol purification unit to the cellulosic industry, in terms of equipment design, input quantification and cellulosic methanol purification.
32

Biocompatibilidade do polissacarídeo celulósico sintetizado por zoogloea sp.: um estudo em bexigas de coelho / Biocompatibilidade do polissacarídeo celulósico sintetizado por zoogloea sp.: um estudo em bexigas de coelho / Biocompatibilidade do polissacarídeo celulósico sintetizado por zoogloea sp.: um estudo em bexigas de coelho / Biocaompatibility of cellulosic expolisaccharide synthesized from sugar molasses by zooloea sp.: a study in rabbit bladders / Biocaompatibility of cellulosic expolisaccharide synthesized from sugar molasses by zooloea sp.: a study in rabbit bladders / Biocaompatibility of cellulosic expolisaccharide synthesized from sugar molasses by zooloea sp.: a study in rabbit bladders

Henrique Lima Gomes 11 July 2012 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Atualmente, o material utilizado para o tratamento endoscópico é o Deflux, porém este é um material não-biológico. Sabe-se que a substância ideal deve ser atóxica, biocompatível, não-migratória, não-antigênica e deve causar o mínimo possível de inflamação no local do implante. A bactéria Zoogloea sp. produz um exopolissacarídeo celulósico (CEP) com baixa citotoxicidade e alto biocompatibilidade. O objetivo deste estudo é investigar, na bexiga de coelho, a biocompatibilidade de implantes de exopolissacarídeo de celulose, produzidos pela Zooglea sp. Foram utilizados como modelo experimental, 20 coelhos adultos da raça Califórnia, com média de seis meses de idade. Os animais foram divididos em dois grupos, sendo o grupo G1, composto por animais mortos três dias após a aplicação do implante (n=9), e o grupo G2, composto por animais mortos três meses após a aplicação do implante (n=11). Cada animal recebeu, no total, quatro implantes, sendo dois de gel de biopolímero e dois de gel Deflux. Foram realizadas as técnicas imunohistoquímicas para marcação de colágeno tipos I e III, alfa-actina de músculo liso, PCNA e reação química TUNEL. Nas amostras de três dias, os implantes de CEP e deflux, eram estruturalmente homogêneos e livres de células inflamatórias ou vasos sanguíneos. Por outro lado, nas amostras de três meses, com exceção de algumas áreas, o CEP estava organizado como feixes curtos que eram sugestivos de um tecido fibroso. Apesar disso, o implante de CEP corou negativamente para colágenos tipos I e III, fibras elásticas, enquanto que o tricrômico de masson, não indicou a presença de colágeno. Em contraste as áreas de implante de deflux nas amostras de três meses estavam fragmentadas, mas ainda eram homogêneas, e ainda não havia nenhuma célula nem vaso sanguíneo em seu interior. As células positivas para PCNA podiam ser claramente percebidas dentro dessas ilhotas, dessa forma indicando um processo inflamatórioproliferativo, em curso. No grupo sacrificado aos três meses, os implantes de deflux ainda estavam negativos, mas em torno das áreas de CEP algumas células positivas para a técnica do TUNEL eram perceptíveis. Nos implantes de CEP de três meses, muitos vasos sanguíneos eram visualizados, e a sua densidade era de 23.865.48. A densidade de microvasos na lâmina própria (41.5111.19) foi significativamente diferente (p<0.001) daquela no implante de CEP. Nossos resultados mostraram que o CEP possui pouca imunogenicidade e se integra melhor no tecido hospedeiro quando comparado ao deflux. Portanto o CEP deve ser um material eficiente em casos em que a incorporação ao tecido é desejada como por exemplo em estruturas de suporte na cirurgia de reconstrução / Actually the material used for the endoscopic treatment is the Deflux, however this is a non-biological material. It is known that the ideal substance should be non-toxic, biocompatible, non-antigenic, non-migratory and must cause the least possible inflammation. Zoogloea SP. bacteria produces a cellulosic exopolysaccharide (CEP) with low cytotoxicity and high biocompatibility.The aim of this study is to investigate, in rabbit bladder, the biocompatibility of CEP implants produced by Zooglea sp.Were used as experimental model, 20 adult rabbits California race, with an average of six months of age. The animals were divided into two groups, being the G1 group, composed of fallen three days after application of the implant (n=9), and the Group G2, composed of animals dead three months after the application of implant (n=11). Each animal received, in total, four implants, being two of biopolymer gel and two of Deflux gel. Imunohistochemistry techniques were performed for marking of collagen types I and III, Alpha-smooth muscle actin, PCNA and chemical reaction tunnel.In samples of three days, the CEP and deflux implants were structurally homogenous and free of inflammatory cells or blood vessels. On the other hand, in samples of three months, with the exception of a few areas, the CEP was organized as short beams that were suggestive of a fibrous tissue. Despite this, the implant of CEP blushed adversely to collagen type I and III, elastic fibers, while the masson, not indicated the presence of collagen. In contrast the areas of deflux implant in samples of three months were fragmented, but were still homogeneous, and still there was no cell or blood vessel in his heart. PCNA positive cells could be clearly seen inside these islets, thus indicating a proliferative-inflammatory process ongoing. In three months, group sacrificed that received deflux implants were still negative, but around the areas of CEP some cells positive for the technique of TUNEL were seen. In the CEP implants carried out three months apart, many blood vessels were viewed, and its density was of 23.86 5.48. The microvascular density in the bladder wall (41.51 11.19) was significantly different (p 0.001) of that in the CEP implant.Our results showed that the CEP has low immunogenicity and integrates better in host tissue when compared to deflux. So CEP must be an efficient material in cases where the incorporation to the tissue is desired such as support structures in reconstructive surgery
33

Extração de xilanas de polpa kraft branqueada de eucalipto / Extraction of xylan from bleached eucalyptus kraft pulp

Luiza Helena Antoniossi Mansini 21 November 2017 (has links)
Este trabalho visa a valorização da fração de xilana presente na polpa kraft branqueada de eucalipto como matéria prima para a produção de xilitol e derivados de xilose. O presente estudo é dividido em dois objetivos principais. A primeira parte é dedicada ao estudo da otimização do processo de extração da xilana da polpa kraft industrial. Para fazer este estudo foi estabelecido um planejamento fatorial utilizando como variáveis a concentração da solução de hidróxido de sódio, o tempo de extração e a razão sólido/líquido (polpa/solução). A resposta empregada para avaliar a eficiência das extrações foi o rendimento de xilana extraída. A melhor condição de extração foi obtida com solução de hidróxido de sódio 14% (m/v), 180 minutos e razão sólido/líquido de 0,06, resultando em 98% de xilana extraída. Na segunda parte, estudou-se o processo de recuperação da xilana a partir das soluções de extração por técnicas de precipitação utilizando ácidos e/ou álcoois. Devido à presença de impurezas no precipitado, estudou-se também o efeito da lavagem dos mesmos. A partir da caracterização das amostras isoladas pode-se concluir que as xilanas isoladas utilizando metanol, isopropanol, ácido clorídrico e ácido nítrico apresentaram graus de pureza comparáveis à de amostras comerciais de xilana. / This work aims the extraction of xylans present in bleached eucalyptus kraft pulp. The extracted xylans can be used as raw material for the production of xylitol and xylose derivatives. The study is divided in two main objectives: The first part is dedicated to optimize the conditions to extract xylan from industrial Kraft pulps. To achieve this, a factorial planning design was established using as variables the concentration of sodium hydroxide solution, extraction time and the solid (pulp) to solution ratio. The response to employed to evaluate the extraction efficiency was the recovery xylan yield. The best extraction condition was obtained with 14% (w/v) sodium hydroxide, 180 minutes and solid (pulp) to liquid ratio of 0.06, which lead to approximately 98% of xylan recovery yields. In the second part of this work, the recovery of the pure xylan from the aqueous solution was carried out by precipitation techniques using acids and / or alcohols. Due to the presence of impurities in the precipitates, it was also studied the effect of washing to purify the samples. From the characterization of the isolated samples it can be concluded that xylans precipitated by using methanol, isopropanol, hydrochloric acid and nitric acid, produced xylans samples with similar level of purity when compared to the commercial standard xylan.
34

Drought response of <i>Populus</i> transformed with stress response transcription factors

Campbell, Alina S 01 August 2010 (has links)
The economic feasibility of producing biomass-based fuels requires high-yielding feedstocks to supply biomass to biorefineries. Populus trees are a potential biomass feedstock due to their high yield, but their high water requirement limits productivity under drought conditions. The number of genes controlling drought tolerance, and the long generation time for perennial species, slows cultivar development. Accelerated domestication proposes using the sequenced Populus genome to quickly incorporate target traits into productive clones by transgenesis. Six putative drought tolerance transcription factors: DREB2A, DREB2B, AtMYB, AREB1/ABF2, MYB, and NAC, had been previously identified and manipulated in eastern cottonwood (Populus deltoides). Three constructs of each gene were transformed into a P. deltoides background clone, including constitutive overexpression (OE), drought inducible OE, and knockdown. This greenhouse study examines the effect of these previously transformed constructs on drought tolerance by characterizing leaf abscission, leaf water potential, and growth under drought and well-watered conditions. AREB1/ABF2 constitutive OE lost significantly fewer leaves under drought than the Vector control, and had one of the lowest rates of leaf loss overall. Both DREB2A inducible OE and AREB1/ABF2 constitutive OE plants were more productive than the Vector control under drought conditions. MYB inducible OE was a productive construct and initially appeared to be drought tolerant. It is possible that this construct experienced xylem cavitation early on due to the severity of drought experienced by the large trees containing this construct. DREB2A inducible OE, AREB1/ABF2 constitutive OE, and MYB inducible OE were the most productive constructs as well as being likely to confer drought tolerance. Field trials would be the next step, providing a clearer picture of how these constructs would perform under natural conditions.
35

Economic Impacts of Production, Storage, Transport, and Conversion of Switchgrass for Cellulosic Ethanol in Tennessee

Fulton, Adam David 01 May 2010 (has links)
The goal of this study is to evaluate the introduction of cellulosic ethanol conversion plants using switchgrass as the feedstock and how it impacts the economies of two Tennessee regions. Switchgrass feedstock production, storage, and transportation costs are estimated for one plant in West Tennessee and one plant in East Tennessee. In each region, the location for a cellulosic ethanol conversion plant and the acreage required to meet a 61.8 million-gallon/year capacity are specified. The costs associated with switchgrass production and cellulosic ethanol conversion are then entered into IMPLAN to estimate the economic impacts of one cellulosic ethanol plant in each region. The key findings of the study for West Tennessee are as follows. The investment impacts of switchgrass farming are $100.4 million more in total industry output, an increase of 914 jobs, and $46.9 million more in total valued added. Investment impacts of a cellulosic ethanol conversion plant include $121.3 million increase in total industry output, an additional 653 jobs, and a $47.7 million increase in total valued added. Year-to-year operations of switchgrass farming and cellulosic ethanol conversion increase the region’s total industry output by $57.1 million, increase jobs by 296, and increase total value added by $26 million. In East Tennessee the investment impacts of switchgrass farming are $118.3 million increase in total industry output, 949 jobs created, and a $66.4 million increase in total valued added. Investment impacts of a cellulosic ethanol conversion plant include a $116.9 million increase in total industry output, an additional 765 jobs, and a $48.3 million increase in total valued added. Year-to-year operations of switchgrass farming and cellulosic ethanol conversion increase the region’s total industry output by $80.4 million, jobs by 396, and the total value added by $39.2 million.
36

Pretreatment Of Cotton Stalks With Ionic Liquids For Enhanced Enzymatic Hydrolysis Of Cellulose And Ethanol Production

Haykir, Nazife Isik 01 February 2013 (has links) (PDF)
This study aims efficient conversion of cotton stalks to cellulosic ethanol through ionic liquid pretreatment and enhanced enzymatic hydrolysis. Among several ionic liquids, EMIMAc exhibited the most striking impact on cotton stalks with respect to the changes in biomass structure and digestibility. Cotton stalks, which were subjected to EMIMAc pretreatment at 10% (w cotton stalks/w EMIMAc) of biomass loading and 150&deg / C for 30 minutes, were found to be 9 times more digestible than untreated cotton stalks. Besides, glucose and ethanol yields, which were based on the cellulose content of untreated cotton stalks, were found as 67% and 66%, respectively. These yields were insufficient regarding efficient conversion of the cellulosic portion of cotton stalks to glucose and ethanol which is linked to the superior solvation capability of EMIMAc towards biomass. In order to enhance aforementioned yields, EMIMAc pretreatment was conducted at 30% of biomass loading. Though lignin extracted was much lower, higher yields were obtained compared to the former case since 96% of cellulose was recovered upon EMIMAc pretreatment and reduced crystallinity was observed for pretreated biomass. Glucose yield was achieved as 84% even at a substrate loading of 15% (w/v). Additionally, 76% of ethanol yield and 3% (v/v) of ethanol titer were obtained upon fermentation. Accordingly, reduction in biomass crystallinity was satisfactory to improve enzymatic accessibility of the biomass. Besides, EMIMAc maintained its effectiveness as a pretreatment agent upon recycling since no change in terms of hydrolysis of pretreated samples was observed upon EMIMAc recycling for three times.
37

Intercellular adhesion in resin canal tissue isolated from slash pine chlorite holocellulose

Kibblewhite, R. Paul 01 January 1969 (has links)
No description available.
38

Zero-Valent Iron Decolorization of the Anthraquinone Dye Reactive Blue 4 and Biodegradation Assessment of its Decolorization Products

Yang, Hanbae 18 April 2005 (has links)
Anthraquinone dyes constitute the second largest class of textile dyes, and are used extensively in the textile industry. A high fraction of the initial reactive dye mass used in the dyeing process remains in the spent dyebath. Reactive dyes are not readily removed by typical wastewater treatment processes and the high salt concentration typical of reactive dyeing further complicates the management of spent reactive dyebaths. Investigation of the reductive transformation of reactive anthraquinone dyes and their decolorization products has been very limited. Additionally, very limited research has been conducted on the decolorization of spent reactive dyebaths. Research was conducted to investigate the key operational parameters of batch and continuous-flow ZVI decolorization of a reactive anthraquinone dye, Reactive Blue 4 (RB4), under anoxic conditions, as well as the potential for the biodegradation of its decolorization products in a halophilic culture under aerobic conditions. The effect of two operational parameters, such as mixing intensity and initial dye concentration, on the ZVI batch decolorization kinetics indicates that ZVI decolorization of RB4 is a surface-catalyzed, mass transfer-limited process. The high salt and base concentrations enhanced the rate of RB4 decolorization. Based on parameters such as porosity, hydraulic conductivity, pore water velocity, and dispersion coefficient, non-ideal transport characteristics were observed in a continuous-flow ZVI column. The results of a long-term continuous-flow ZVI decolorization kinetics demonstrated that continuous-flow ZVI decolorization is feasible. However, column porosity losses and a shift of reaction kinetics occur in long-term column operation. ZVI decolorization of RB4 was successfully described with a pseudo first-order or a site saturation model. Lastly, the RB4 decolorization products generated by ZVI treatment had no inhibitory effect on the halophilic culture. However, biodegradation and/or mineralization of RB4 decolorization products was not observed after a long-term incubation of the culture. This research demonstrated the feasibility of ZVI decolorization of reactive anthraquinone dyes, which will help in the development of a continuous-flow, dyebath decolorization process and the possible reuse of the renovated dyebath in the dyeing operation. Such a system could lead to substantial reduction of water usage, as well as a decrease of salt and dye discharges.
39

Economic Impacts of Production, Storage, Transport, and Conversion of Switchgrass for Cellulosic Ethanol in Tennessee

Fulton, Adam David 01 May 2010 (has links)
The goal of this study is to evaluate the introduction of cellulosic ethanol conversion plants using switchgrass as the feedstock and how it impacts the economies of two Tennessee regions. Switchgrass feedstock production, storage, and transportation costs are estimated for one plant in West Tennessee and one plant in East Tennessee. In each region, the location for a cellulosic ethanol conversion plant and the acreage required to meet a 61.8 million-gallon/year capacity are specified. The costs associated with switchgrass production and cellulosic ethanol conversion are then entered into IMPLAN to estimate the economic impacts of one cellulosic ethanol plant in each region. The key findings of the study for West Tennessee are as follows. The investment impacts of switchgrass farming are $100.4 million more in total industry output, an increase of 914 jobs, and $46.9 million more in total valued added. Investment impacts of a cellulosic ethanol conversion plant include $121.3 million increase in total industry output, an additional 653 jobs, and a $47.7 million increase in total valued added. Year-to-year operations of switchgrass farming and cellulosic ethanol conversion increase the region’s total industry output by $57.1 million, increase jobs by 296, and increase total value added by $26 million.In East Tennessee the investment impacts of switchgrass farming are $118.3 million increase in total industry output, 949 jobs created, and a $66.4 million increase in total valued added. Investment impacts of a cellulosic ethanol conversion plant include a $116.9 million increase in total industry output, an additional 765 jobs, and a $48.3 million increase in total valued added. Year-to-year operations of switchgrass farming and cellulosic ethanol conversion increase the region’s total industry output by $80.4 million, jobs by 396, and the total value added by $39.2 million.
40

Nya t-shirts av gamla jeans : Textila egenskaper hos en cellulosabaserad konstfiber tillverkadav dissolvingmassa framställd från bomull av textilt avfall / New t-shirts made out of old jeans

Aronsson, Julia, Björquist, Stina January 2015 (has links)
Idag produceras 70 miljoner årston textilfibrer. Denna siffra kommer fram tills år 2050 att mer än tredubblas i takt med att jordens befolkning och medelinkomsten per person ökar. År 2013 förbrukade svenskarna så mycket som 12,5 kilo textil per person varav 8 kilo slängdes i hushållssoporna. Textilindustrin ställs inför stora utmaningar, dels att tillgodose ett större behov av fibrer samt att hantera ett växande avfallsberg. Det behövs därför återvinningsmetoder för att ta tillvara på textiler både från industrier och konsumenter. Företaget Re:newcell finansierar forskning på Kungliga Tekniska Högskolan, KTH, i Stockholm. Denna forskning undersöker möjligheten att återvinna cellulosabaserat textilavfall till en dissolvingmassa. Massan kan användas för att spinna nya cellulosabaserade konstfibrer. I detta examensarbete undersöks egenskaperna hos lyocellfibrer framställda av dissolvingmassa från Re:newcell. Dissolvingmassan för dessa fibrer har producerats av secondhandjeans. Fibrerna jämförs genom projektet med konventionellt framställda lyocellfibrer, Tencel®. På Textilhögskolan har ett ringspunnet garn producerats av respektive fiber. Garnernas linjära densitet har kontrollerats för att uppnå samma grovlek som ett kommersiellt producerat Tencel®garn. Dragprovning av samtliga tre garner har utförts för att bestämma tenacitet samt brottstöjning. En slätstickad trikåkvalitet har sedan tillverkats av respektive garn. På dessa tre trikåkvaliteter har ett antal tester utförts för att kunna bestämma kvadratmetervikt, dimensionsändring efter tvätt, fuktlednings-, absorptions- och färgupptagningsförmåga, anfärgning till andra material, färghärdighet efter konsumentvätt, nöthärdighet samt matrialens tendens att noppra. Syftet med arbetet är att kunna dra slutsatser om huruvida Re:newcellfibern kan komplettera konventionellt producerade cellulosabaserade konstfibrer för tillverkning av nya klädesplagg. Slutsatsen är att Re:newcellfibrerna kan spinnas till ett garn med samma linjära densitet som ett kommersiellt framställt Tencel®garn. Re:newcellgarnet har en god styrka och töjs i liten utstäckning i både torrt och vått tillstånd. Av garnet är det möjligt att tillverka en rundstickad vara av slätstickad kvalitet. Efter testerna kan det konstateras att detta material krymper accepterbart vid konsumenttvätt. Det kan bäras nära kroppen eftersom absorptions- och fuktledningsförmågan är god. Färgupptagningsförmågan är god för reaktivfärg av antrakinon typ. En del av färgen tvättas av men materialet anfärgar inte andra material märkbart. Re:newcelltrikån står emot förhållandevis hög nötning mot en standardiserad ullväv. Materialet noppras i stor utsträckning rätsida mot rätsida men nopprorna slits av efter hand. Testerna som har utförts på materialen visar att Re:newcellfibern har utmärkta egenskaper för att kunna användas i ett plagg som till exempel en t-shirt. Därmed har dissolvingmassan från Re:newcell en stor potential att vara en ny råvara i produktionen av cellulosabaserade konstfibrer. Dissolvingmassan kan bidra till att textilindustrin kan ta tillvara sitt avfall och även tillgodose en del av det växande behovet av textilfibrer i framtiden. / The population of the earth, as well as the average income, are both on the increase. Therefore the already high consumption of textiles in the world is expected to be even greater in the future. At present, 70 million tonnes of textile fibres are being produced yearly. This figure could rise to as much as 240 million within the next 35 years. In Sweden alone, the people were consuming around 12.5 kilos of textiles per person in 2010. About 8 of these kilos were discarded as garbage. The textile industry is facing big challenges, both in finding new resources for production of fibres as well as dealing with the issue of large amounts of textile waste from consumers and companies. Re:newcell is a Swedish company financing research at Royal Institute of Technology, KTH, in Stockholm. Their researchers are investigating the possibility to recycle cotton and other cellulosic textile materials in order to produce dissolved pulp. Thereafter cellulosic man-made fibres are being produced from the pulp. The properties of lyocell fibres produced from the dissolved pulp from Re:newcell is being investigated in this Bachelor thesis. The dissolved pulp has been produced from jeans bought in second-hand shops. These fibres are being compared to the conventionally produced lyocell fibres, Tencel®. A ring spun yarn of each fibre type has been produced at the Swedish School of Textiles. The linear density of the yarns have been determined in order to achieve the same thickness of the yarn as a commercially spun yarn also made from Tencel® fibres. A test of tensile strength and elongation has been carried out on each of the three yarns. Thereafter the yarns have been used to manufacture a knitted fabric on a circular knitting machine. Each of the knitted fabrics have gone through a series of tests regarding weight of fabric per square meter, dimensional change after washing, wicking and absorbency properties, dye exhaustion, colour staining to other materials during laundering and colour change after laundering, abrasion resistance and tendency to create fuzzing and pills. The purpose of the study is to make conclusions about whether this fibre has the potential to complement other cellulosic man-made fibres. The conclusion is that Re:newcell fibres can be used to spin a yarn with the linear density of 25 tex. This yarn can be utilized to produce a circular knitted fabric light enough to make T-shirts. After the testing it is concluded that the shrinking percentage after consumer’s washing is acceptable. In addition, the material could be worn close to the body because of the good absorbency and wicking properties. The exhaustion of dyestuff of antrakinon type from the dyeing liquor is equally very good. Although some of the dyestuff is being washed in laundering, the Re:newcell tricot is not staining other materials noticeably. The Re:newcell material can also withstand high abrasion against a woven wool material. The tendency to form fuzzing and pills is great but the pills are being torn of eventually. It may be concluded that the fibres, made by the dissolved pulp of Re:newcell in the lyocell process, can be used to manufacture a yarn with better strength than two investigated yarns of Tencel®. The tests carried out on the fabrics produced in the project show that the Re:newcell fibre has excellent properties in order to function as a material in a garment, for example a T-shirt. Therefore the dissolved pulp of Re:newcell has the possibility to be a new raw material in the production of man-made cellulosic fibres. This enables the textile industry to deal with their excess waste, and to meet the increasing demand for fibres in the world.

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