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106 Uppsatser om Dissolving pulp - Sida 6 av 8

Experimentell studie av kinetiken vid peroxidblekning av pappersmassa

Vid TCF-blekning av pappersmassa är väteperoxid en av huvudkemikalierna. I dagsläget är det svårt att styra blekstegen. Operatörerna måste ta hänsyn till produktionstakt, blekbarheten på massan varierar och fördröjning i trender. PO-bleksteget på Södra Cell Värö har en ungefärlig uppehållstid på 4 timmar och det är först efter så lång tid som man kan se hur en förändring verkligen slår igenom. Överblekning kostar väldigt mycket i kemikalieåtgång och det är därför efterfrågat ett sätt att kunna styra och optimera peroxidblekningssteget.

Energikartläggning av integrerat massa- och pappersbruk

Målet med detta examensarbete har varit att utföra en energikartläggning på Nymölla Bruk med utgångspunkt i företagets be?ntliga energiaspektregister. Syftet har varit att tydliggöra hur energianvändningen på Nymölla Bruk ser ut. Bakgrunden till detta arbete är företagets deltagande i programmet för energieffektivisering i energiintensiv industri (PFE).I examensarbetet har en energikartläggning på Nymölla Bruk för år 2010 utförts. Fallstudien delades in i två steg där första steget i studien var att kartlägga energi?ödena in och ut från bruket.Andra delen av studien innefattade att kartlägga de interna processerna och deras energi?öden.

Avsättningar i pappersmaskiner : Utbildning och förslag till processförbättringar

Deposits can be formed in the paper machine due to sticky materials from wood and recycled paper. These deposits get stuck on process equipment and cause the product quality to deteriorate and the efficiency of the paper machine is reduced. The purpose of this thesis is to increase the understanding about deposits among machine operators, and to suggest methods that can be used to reduce the amount of deposits formed in Bravikens paper machines.To fulfill the purpose of the thesis a pre-study, a literature review and interviews with machine operators and production staff, were carried out. These methods led to the planning and creation of an education about deposits for machine operators.The education about deposits for machine operators consisted of an interactive lecture to introduce the subject of deposits and a subsequent discussion. This approach was chosen to give the machine operators the opportunity to discuss their work situation on the paper machines related to their new knowledge about deposits.

Reducering av produktionstryck i A-linan : Förflyttning av produkt

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

The effect of new raw materials on pellet prices

As demand for renewable energy is increasing rapidly, the market for biomass pellets is expected to continue to grow in the near future. Most of the new raw materials that are discussed for pellet production have one thing in common; the production costs will increase compared to using traditional raw materials such as sawdust and planer shavings. The aim of this thesis is to investigate to what degree increased use of new raw materials for pellet production will affect the general pellet prices in Sweden and to survey what plans Swedish pellet producers have concerning new raw materials. To investigate the raw material situation of the Swedish pellet producers an industry survey was performed. Literature studies were also made on previous research in the subject field. Calculations of the production costs for pellets were done for the raw materials sawdust, wet sawmill chips and energy wood respectively. New raw materials are already used by the large-scale pellet producers in Sweden.

Sortimentsinriktad avverkning

Forest enterprises have always searched for ways to improve efficiency. For the past few years there has been an emphasis on stock-keeping levels. Increased demand for fresh round timber and the need to decrease the amount of tied-up capital has made the forest industry reduce its inventory levels. This has brought on a higher demand on the timber supply from the forest management districts concerning both delivery in time and assortment output. As a result, the flow of timber has fluctuated a lot with serious consequence for the timber supply during 1994.

Vattensänkningar : en analys av orsaker och effekter

There are records of lowering of the water level in a lot of the Swedish lakes from the middleof the 1700th century. The aim was gaining more areable land to meet the needs of more foodto support the expanding population. In areas with top soil which contents of clay or loam asin the southwest of Scania in southern Sweden this was proven to be a successful wayexpanding the total outcome of the harvest.The studied area in the northeast of Scania, though, consists of morain with a lot of mires -much less nutritious conditions. When the water level is lowered the atmosphere gets accessto the peat. The dissolving of the organic matter that has been suppressed by the lack ofoxygene below water level continues.

Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser

Most of the saw and pulp industries have stored wood nearby their production, the main reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality. One drawback of wet storage of wood is the leaching of chemical substances into the surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and organic substances. These substances can cause problems for the surrounding environment. The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.

Äppelpressmassa i Sydsverige - nuvarande användningsområden och möjligheter till nya produkter

Pomace is the solid remains (i.e. stems, pulp, seeds, and skins) after pressing for juice. The annual production of apple pomace is 593 000 ton worldwide. Its field of application depends on local conditions. In order to investigate the field of application of apple pomace in the Southern Sweden, six persons on companies with production of apple juice were interviewed.

Användning av CAD-data vid NC-programmering

The degree project is performed at Metso Kamfab. The production is aimed on machines everything from handling of fiber to paper pulp. Metso Fiber and Kamfab are using Pro/Engineer for design and blueprint production. The processing department types the NC-programs in notepad on the basis of the blueprints, the CAD-dates that already is there are not used. The aim with the work is to study if Kamfab can use CAM-system for processing and production of programs for their NC-machines.

Fertilization in Eucalyptus urophylla plantations in Guangxi, southern China

StoraEnso decided in year 2002 to build a pulp mill in the province of Guangxi, southernChina, and also establish eucalyptus plantations to provide it with raw material. By 2010StoraEnso controls about 90 000 of planned 120 000 ha, out of 75 000 ha is already plantedwith Eucalyptus.By using better genetic material, improve the tending, selecting the sites more careful and byusing a proper fertilization regime StoraEnso hopes to increase the mean annual incrementfrom today?s 25 m3/ha, on bark, to 35 m3/ha. This study is one part in this work to increase themean annual increment in the plantation.This master thesis is the forth in a series, that has followed up a fertilization trial that startedin spring 2006 when the trial was laid out and treatments decided. The aim with the trial is toexamine the production potential of Eucalyptus urophylla in Guangxi, southern China.

Förhållandet mellan COD och TOC i skogsindustriella avlopp

Under tillverkningsprocessen i massa- och pappersindustrin bildas avloppsflöden i flera olika steg. Ett av de miljöbelastande utsläppen utgörs av organiskt material. Organiskt material kan mätas som biokemisk syreförbrukning (BOD), kemisk syreförbrukning (COD) eller som totalt organiskt kol (TOC). Analys av COD inkluderar ofta miljöfarliga ämnen (till exempel kvicksilver). Naturvårdsverket har under flera år aviserat att analysen kan komma att förbjudas och därmed blir analys av TOC allt mer vanligt.

Att tänka utanför arket : En kartläggning över samarbeten som lett till produktinnovationer inom svensk pappers- och massaindustri

För drygt ett decennium sedan började marknaden för tryckpapper att vika. Den svenska pappers- och massaindustrin fick en ny annorlunda konkurrent genom introduktionen av till exempel smarta telefoner och surfplattor. Utvecklingen har medfört att svenska pappers- och massaföretag i högre utsträckning har börjat titta på mer radikala innovationer i sin produktutveckling där nya användningsområden för träråvaran utforskas, en inriktning som kräver kompetenser utöver de som bolagen besitter internt.Studiens syfte är att undersöka olika samarbetsformer inom svensk pappers- och massaindustri för att kartlägga vilka faktorer som varit, och är, framgångsrika för produktinnovationer. Ambitionen är också att undersöka om det skett en förändring i samarbetenas karaktär under de senaste 25 åren. De företag som deltagit i studien ärSCA, Södra Cell, Holmen/MoDo, Stora Enso, BillerudKorsnäs och Rottneros samt ett antal samarbetspartner till dem.Resultaten visar att såväl samarbetsformer som vilka aktörer svensk skogsindustri samarbetar med har förändrats i stor utsträckning.

Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm

In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime.

Två nya trailerkoncept för transport av rundvirke hos Stora Enso : en analys av prestation och flexibilitet

The need for roundwood transport capacity vary throughout the year. The need during a period is influenced mainly by the volume transported the period, the number of days during which transport can be carried out, seasonal variations in road conditions and the weight of the roundwood, and the origin of the wood (private forest owners/ forest companies). The need for transport capacity generally increase during the winter and in spring, after thawing. Lack of logging trucks combined with a lack of drivers for these trucks make it hard to hire extra help during periods of increased transport capacity needs. It is also very expensive to keep logging trucks for use only during these periods. In this thesis, two new concepts based on the partial transport by truck tractors have been examined, to find out the possibility for increased performance and flexibility.

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