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272 Uppsatser om Acid sulfite pulp - Sida 2 av 19
Förutsättningar att utforma stationsbatterier i vattenkraftverk med Li-jonteknik
In hydropower plants it is necessary to always have local power supply. Therefore, the plants are equipped with batteries as stationary back up power. Vattenfall Vattenkraft is using lead acid batteries but has been investigating alternatives to replace them. The aim of this study is to investigate the potential of using Li-ion technology as back up power.The study showed that Li-ion batteries have many qualities. The Li-ion technology will decrease the space and maintenance demand.
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.
Effect of botanically diverse pastures on the milk fatty acid profiles in New Zealand dairy cows
Botanically diverse pastures are commonly used in New Zealand to reduce the ruminant environmental impact by reducing the methane production from the rumen digestion. In order to evaluate the effects diverse pasture species have on the milk fatty acid profile seventy-two lactating Friesian-Jersey crossbred dairy cows were used in a randomised block design with two replicates of six treatments. Six different pasture mixtures were fed at a daily allowance of approximately 15 kg DM/cow/day. The mixtures were categorised as either a simple or a diverse pasture. The simple mixtures all contained white clover with the addition of either a standard diploid perennial ryegrass (RG), a diploid high sugar ryegrass (HS) or tall fescue (TF).
Analys av tanniner : från granbarksextrakt
The objective for this master?s thesis was to test and evaluate two methods for determining the content of tannin in a pinebarkextract. The methods used at Södra for this previously have not been specific enough, only the amount of polyphenolics have been measured. One of these methods is a test based on the Stiasny test and it determines the extracts ability to form a gel with formaldehyde. When this test was carried out it showed that the extract did not contain much tannin.
Strängluftning av vallfoder : Inverkan på ensilagets torkningförlopp, spill och smörsyratillväxt
When harvesting ley you hope to get a fast drying and a faster harvest. If there is a
system with round bales, you need to have a dry matter close to 45 %. To make this as
fast as possible, there is made a machine which pick up the grass with an pick-up. It
turn the grass over and put it behind the machine (figure 2 and 4). There are few tests
to prove the efficiency of this machine.
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.
Kemisk karaktärisering samt nedbrytning av process- och avloppsvatten vid SCA Ortvikens pappersbruk
During pulp and papermaking process a huge amount of water is used. The wastewater contains a large amount of pollutants and has to be treated before it reaches the recipient. In March 2004 a new bleaching plant was started up at SCA Graphic Sundsvall AB, Ortviken?s paper mill using peroxide. The production of bleached thermo mechanical pulp and thus the load to the wastewater plant increased.
Investigation of yeast Grown in SSF Dring Biothanol Production from Lignocellusosic Material
Ethanol produced from lignocellulosic biomass has the potential to become a promisingalternative to gasoline. In this work the simultaneous saccharification and fermentation (SSF)technology was applied for ethanol production from hardwood with focus on cell growth,ethanol production and contamination.The SSF was performed at PH 5.5 and 35°C for different suspended solid concentrations(8%, 10% and 12%) of pretreated birch slurry which contained 16 % total suspended solids.Two different hexose fermenting yeast strain (Ethanol Red) and pentose fermenting yeaststrain were used.Quantifying the concentration of chemical components and metabolites in the fermentationmedium demonstrated that glucose and xylose are the major fermentable sugars in the slurry.The higher load of slurry (12%) represents a higher content of carbohydrates and potentiallyhigher end concentration of ethanol. Moreover, more lactic acid is produced with the lowerload of slurry (8 % or 10 %), presumably due to a result of a less inhibitory environment forbacterial growth. In this context, acetic acid sticks out as the most important inhibitor withconcentrations of 15.2 and 12.5 and 9.7 g/l respectively in the 12 %, 10 % and 8 % (ofsuspended solids) trials. Using pentose fermenting yeast may lead to higher ethanolproduction, lower xylose uptake and lower lactic acid formation.
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.
Förekomsten av sura sulfatjordar i Mälardalen : -en pilotstudie utförd åt SGU
Acid sulphate soils is a wide spread problem along the northern coast of Sweden. This is causing great damage through low pH and leaching of metals out into the streams. These soils are estimated to be found in several places in Sweden but also in many other areas in the world. One of these areas in Sweden that are believed to contain these sediments is Mälardalen. The purpose of this study is to evaluate the extension of the acid sulphate soils in this area.
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.
Lättlösliga kolhydrater i vallfoder och i hästens grovtarm :
The purpose of this study was to investigate how the content of glucose, fructose, sucrose and fructan (WSC) varied in silage, haylage and hay harvested from the same field and at the same time of harvest. The study also investigated if differences in the WSC-fraction in the forages caused differences in composition of WSC in the colon of horses fed the forages. Hay, haylage and silage were harvested in the first week of June 2005 and stored for about nine months before feeding. Horses that were fistulated in right ventral colon and caecum were used, but only the colon fistula was used for sampling.
The fresh crop and the conserved hay, haylage and silage were analyzed for chemical composition and WSC-fraction.
Fermenterat blötfoder till gris
The purpose of this literature study was to examine what kind of composition fermented liquidfeed can have, what a desired composition is and possible advantages and disadvantages onhealth and growth performance of the pig. A well fermented liquid feed is characterized by a lowpH (.
Kemin bakom framtidens avgasrening : En studie av ureasönderfall under kvävgasatmosfär
The purpose of this work was to provide a better understanding of urea?s decomposition and byproduct formation in an SCR system on heavy trucks. In my experimental setup with TGA-DSC-FTIR (a combination of two thermal analysis methods and a method for gas phase detection), an FTIR method for urea in the gas phase was developed for the qualitative and quantitative determination of urea and its decomposition products. Chemicals such as urea, biuret, cyanuric acid and melamine of p.a. quality were used in this method development. Beforehand, there was no FTIR method available to detect these substances; hence, the aim of this work was to develop an FTIR method to understand the degradation chain of urea. The combination of TGA and DSC was used for analysis of different samples, where urea, biuret, cyanuric acid and melamine in varying amounts have been weighted in for various experiments in order to study the temperature at which a phase transition or reaction occurs, i.e.