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106 Uppsatser om Dissolving pulp - Sida 1 av 8

Aktivering av en dissolvingmassa med enzymer före en konventionell viskosprocess

In conventional viscose manufacturing, a large amount of carbondisulfide is consumed. This amount has to be decreased to keep the production cost down and to reduce the environmental impact. The purpose with this work was to show if an enzyme treatment of a Dissolving pulp could increase the degree of substitution in the viscose so that the amount of carbon disulfide consumed in the process could be decreased. Previous investigations by Kvarnlöf (2007), Engström et.al. (2006) and Henriksson et.al.

Optimering av blekeriet i CTMP-linjen vid Rottneros Bruk

At Rottneros pulp mill mechanical pulp is bleached with hydrogen peroxide. The changes of bleaching chemicals that are used for different grades are taken from bleaching tables; however these tables are old and need to be updated. The purpose of this thesis was to be the basis of new documentation.In this thesis three pulps where studied with the aim to find the optimal bleaching chemical changes (total NaOH/VP-quote) for each pulp. The pulps were taken from the filter before the bleaching tower and the pulps were bleached in the lab. The most important pulp property in this study was the brightness and how that was influenced by the chemical dosages.

Utveckling av Pappersmassestol

The author contacted designers Claesson Koivisto Rune Arkitektkontor in August 2007regarding his Master thesis at KTH. The company had discussed the possibility of creating achair made from molded pulp. The author was taken on as a manager for the project. Theobjective was to produce design documentation for a paper pulp chair which was to belaunched at the in 2008 Milan Furniture Fair. The purpose of the thesis was to develop aproduct with scientific methods as well as to investigate how to make collaboration betweendesigners and engineers easier through communication.The project went through four basic stages: Information, Analysis, Synthesis and Evaluation.Information on paper pulp, molded pulp, chair design, sitting postures and the existingmarket of molded pulp furniture.

En studie av utvecklingen av drivningsnettot i skogsbruket :

This master thesis consists of an investigation of the profitability per hectare in privatly owned forest land. The investigation is based on data collected from Skogsstyrelesen, Riksskogstaxeringen and Skogsforsk. During the last twenty years the prices on pulp wood and saw log have substantial decreased, but during the same time the the volumes from final felling have increased and the cost for felling has decreased, this investigation shows how the netprofit per hectARE after final felling has changed between year 1980-2005 This investigation shows that that the netprofit has stayed on a stable level during the years 1985-2005 even though prices pulp wood and saw log decreased. Much indicates that the demand of swedish pulp wood and saw log will continue to be strong or even stronger wich will give increased prices and an higher netprofit after final felling in the future.

Simulering av COD-fraktioner i en aktivslamanläggning vid en sulfatmassafabrik

This thesis work was made for Södra Cell Mörrums bruk in Blekinge. The purpose of the work was to develop a computer model in the simulation program Extend for the removal and balance of organic oxygen consuming substances, measured as COD (Chemical Oxygen Demand), in the new biological treatment plant in the mill. The plant produces two different pulp products, TCF- (Totally Chlorine Free) pulp and ECF- (Elementary Chlorine Free) pulp, for sale. The different bleaching procedures affect the characteristic of the wastewater and thus the effectiveness of the biological treatment plant.In the model that was developed the COD in the wastewater was divided into five different COD-fractions: soluble easily degradable (SS), soluble hardly degradable (SR), soluble inert (SI), particulate inert (XI) and particulate biomass (XB). To create the model FlowMac? was used as a base.

Energieffektivisering genom förvärmning av flis till kokare med sekundärvärme

The Swedish pulp and paper industry meets higher demand for energy efficiencyi mprovements with increasing energy prices and changes in the Swedish renewable energy certificate system. One action of energy efficiency improvement is by using secondary heat, that otherwise would have been treated as waste heat, for use in a system with lower temperature demands. The aim of this Master´s thesis is to identify possible secondary heat sources in a typical Swedish pulp and paper mill and to investigate what economic benefits the secondary heat will provide when being used for pre heating of wood chips to a kraft digester.The Master´s thesis focuses on three secondary heat sources; dry warm air, warm water and moisture saturated warm air located inside the pulp or paper mill. Two types of kraft digesters are simulated within this study, a typical Scandinavian digester and a modern twin vessel steam phase digester.Due to quality aspects and low temperature level drying is the drying technology with dry warm air rejected. Using warm water in direct contact with wood chips increases the quantity of water to the evaporation plant and thus reduced pulp or paper production and is therefore also rejected.

Systemanalys flingtork : Produktionseffektivisering

BillerudKorsnäs is a leading global provider of primary fiber-based packaging materials and on Gruvöns Bruk in Grums, they have chosen to invest millions in the boiler at the facility to increase the total capacity of the factory. This results in the Pulp Flash Dryer at Gruvön being burden more, which makes it important that it is of great reliability and can be run with a high capacity. The reliability of the Pulp Flash Dryer at Gruvön is not as good as one could hope, which leads to reduced availability and production, as well as to increased maintenance costs. There are a number of different reasons for this, but all the casual links are not known.The purpose of this project was to perform a system analysis of the Pulp Flash Dryer to identify bottlenecks and the most critical parts from a capacity- and availability perspective. Appropriate methodology for the system analysis was used and would be used in a structured way to perform the analysis with data from the process and the maintenance system.

Lämpliga främmande trädslag för Kalmar och Mönsterås kommuner

This report concerns the for Sweden foreign tree species hybrid larch, hybrid aspen and poplar, and focuses on the area Kalmar and Mönsterås municipalities. The report shows that there are not only advantages with these species. The larch, the most common of the alien tree species has the greatest problems due to that its timber is difficult to sell in the area but also the Larch´s poor pulp quality and is more likely to be damaged by wildlife than the spruce is. Hybrid Aspen is much easier to sell and is used like regular aspen for match wood and textile pulp. Its disadvantage is the high cost for plants and to prevent damage from wildlife.

BAMBUVISKOS ? En hållbar fiber för framtiden?

Naturskyddsföreningen gav författarna uppgiften att undersöka förekommande viskosprocesser och alternativa regenereringsprocesser, detta för att identifiera hur hållbara de är ur ett miljöperspektiv och vilka processer som går att applicera på bambu. Detta för att se möjligheten att märka bambuviskos med Bra Miljöval och för att klargöra frekvent uppkommande frågor angående bambuviskos. Syftet är att se på de olika processernas kemiska innehåll samt vilka utsläpp de orsakar till luft och vatten. Ett delmål med rapporten är att den ska kunna användas som material vid vidareutveckling av kriterierna för Bra Miljöval Textil. Resultat som erhållits vid jämförelser av studerad litteratur är att de betydande faktorerna för miljöpåverkan från massaframställningen samt viskos- och lyocellprocessen beror av: använda kemikalier i processen, energianvändningen och vilken typ av energi, möjligheten till rening av utsläpp till luft och vatten samt återvinning av energi och kemikalier.

Ekonomiska konsekvenser av förändrad röttolerans vid Bravikens Pappersbruk :

The competition for Norway spruce pulp wood in Central Sweden increases, forcing the supply-structure of Holmen to face two important challenges. Firstly, it is of the outmost strategically importance to secure the long-term supply of Norway spruce pulp wood to the industries. Secondly, Holmen desires to increase the obtainable volume of Norway spruce pulp wood. This would enable the company to choose volumes in the lower price-segments and thereby decrease the dependency of costly marginal volumes. As this work shows, one part in managing these challenges could be to lower the quality standards concerning root rot (Heterobasidium annosum). Facts presented in the work shows that: 1. Technically, the TMP-industry of Braviken can handle a much more rotted pulp wood than that used today, although the cost of refinement increases.

Analysis of eucalyptus plantations on the Iberian Peninsula

This thesis analyses the prerequisites, profitability and competitiveness of eucalyptus plantation on the Iberian Peninsula and in Brazil. The thesis has a macro perspective and analyses a typical hectare of eucalyptus in each studied region. A survey methodology was used as a strategy to cover a broad perspective using expert respondents. The regions studied on the Iberian Peninsula were the ones found suitable for eucalyptus plantations from an economic point of view. The studied regions were Huelva in the South West of Spain, Galicia in the North West of Spain and Portugal.

Oförutsägbar fiktion : Narratologiska brott och kontraster i Quentin Tarantinos Pulp Fiction

Hösten 1753 utlyste drottning Lovisa Ulrikas Witterhetsakademi en tävling där de deltagande skulle skriva om ett (eller flera) av tre ämnen: en historisk uppsats på prosa, en skönlitterär behandling på prosa, och ett ?Poeme öfwer Konung Carl Gustafs Tåg med sin Krigshär öfwer Bälterna år 1658?. Ett av de bidrag som kom in till tävlingen, om än för sent för att delta, var Hedvig Charlotta Nordenflychts bidrag Konung Carl Gustafs tog öfwer Bält 1658.1 Hedvig Charlotta Nordenflycht var 1700-talets mest kända kvinnliga författare och känd för bland annat Den sörjande Turtur-Duvan, Fruentimrets försvar och Tankar om lovskrifter över de Döde, men allt hon skrev har inte fallit litteraturhistorikerna på läppen. Ett sådant exempel är Konung Carl Gustafs tog öfwer Bält, som sågats ganska grundligt..

Utveckling av mothållssystem till valsar

This Master Thesis is a product development project that has been carried out incooperation with Metso Paper Sundsvall AB. The task has been to develop a holdingsolution that generates force between two rolls and to evaluate the new solution withrespect to functionality, manufacturing, structural stability, costs, assembly etc. Theroll holding solution is a system that is part of a rollpress. The rollpress is used towash and dewater pulp. The existing solution creates forces that have to be absorbedby the gable of the press.

Fire impact in the wood quality and a fertilization experiment in Eucalyptus plantations in Guangxi, southern China

Chinas government has a multifunctional program for a more sustainable forestry since 2000. This six key forest programs goal is to develop a more sustainable forest sector but also take environment consideration. The state forest administration in China has decided to create 5.8 million hectare of fast growing and high yield forest. Eucalyptus has showed to have good properties for pulp and timber production and therefore Eucalyptus plantations are under development in costal areas in southern China. By adding extra nutrients, growth can be enhanced in Eucalyptus plantations.

Analys av massapumps- och mixerarbete vid Metsä Board Sverige AB, Husums Fabriker : Energibesparingsåtgärder vid blekeri 4 & 5 med jämförelse mot ny utrustning

Husums plant has a selection of different pulp pumps at bleaching plant 4 and 5. The displacement- (HC-pump, Sund Defibrator PTD-60) and centrifugalpumps (MC-pump, MCA 42-200, MCP 30/20) are of interest in this report. The centrifugal pumps are controlled by throttle valves, which result in an energy loss. Chemical mixers are used to mix ClO2 into the pulp before proceeding into a holding tower where the bleaching process occurs.The energy demand of the different positions has been measured or calculated to be used in comparisons against new equipment. Quotations were requested and delivered from Valmet and Sulzer.

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