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4495 Uppsatser om High tempreature drying - Sida 2 av 300
Modellering av en panna med rörlig rost :
The aim of this master thesis was to create a dynamic model for the processes in a solid fuel boiler of the moving grate type. Another aim with the model was to keep it as simple as possible but still able to catch the dynamics of the processes in the bedplate of the boiler. The creation of the model had its origin from drying and combustion equations used in earlier modeling work of boilers. The represented model has been used to simulate different kinds of disturbances in a boiler and different ways to control the boiler. These tests show that controlling a number of parameters in the bed of the boiler is an effective way to keep the grate stable during disturbances.
XRF-analys av förorenad mark : undersökning av felkällor och lämplig provbearbetning
X-ray fluorescence (XRF) detection of heavy metals is a cost- and time-effective method for investigation of polluted areas. Compared to laboratory analysis, XRF analysis is limited by high detection limits and uncertainties in some situations. Preparation of samples is known to affect the results of measurements.The purpose of this thesis is to bring a deeper understanding of how different factors affect the results of XRF-analysis. A large number of measurements have been made with the instruments Niton XLt 700 and Niton Xli 700. Results from measurements of lead, zinc and copper have been analysed.This study has shown that a greater moisture content will give a lower measured concentration for the same sample.
Inverkan av torrsubstanshalt och temperatur på kompostens syrabildning :
Composting is a process in which organic matter is mineralized by microorganisms. In January 2005 landfilling of organic waste was prohibited in Sweden. With this prohibition composting has become an important alternative to handle the produced organic wastes. One problem with continuous small-scale composting is the production of organic acids that will inhibit a further composting process. The aim of these theses was to study what effects temperature and dry matter content had on the production of organics acids, and what effect the organic acids had on the mineralisation of the substrate as well as the stability during storage of the product.
Torkad eller gastät lagrad spannmål till värphöns : en fallstudie
The purpose with this study is to compare different systems of grain storage from a
financial point of view. Grain that is supposed to be fed to laying hens.
The systems that were compared were different airtight storage of grain and a system of
conventional storage.
To make this case study I choose to compare four different systems. In the case study
there was one system with bin drying of the grain, two systems with airtight storage of
the grain and one system where you buy dried grain during the season.
I made several of capital investment appraisal where I found the cost of each system,
then I took the cost and divided it with the total grain use and calculated the cost for
each kilogram of grain, and also the cost of the feed.
Then I compared the cost from my case study with the cost of buying feed.
All the systems except for one, gave a lower cost for the hen feed than buying feed from
a dealer The best system, witch were bin drying lower the cost with about 80 000:- SEK.
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.
Användning av rötrest från kombinerad etanol och biogasproduktion : en jämförelse mellan tre alternativ
Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by
Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer
(system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in
terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.
Uppfattningar om tryckved bland träbearbetande företag i Sverige :
The primary purpose of this study has been to investigate the Swedish timber industry?s
perception of compression wood. A secondary aim has been to describe particular areas
within the production process where compression wood is likely to cause problems.
This study has mainly been carried out as a questionnaire. In order to connect the findings to current research, additional information has also been collected by means of a literature review. The questionnaire has been intended for sawmills and wood-manufacturing companies from various production classes and owner categories, as well as from different parts of the country.
Gårdsbaserade system för spannmålshantering i den framtida Lantmännenorganisationen :
The Swedish cooperative Lantmännen Ekonomiska Förening has initiated a project labelled "Operation Blåljus" that includes an extensive program for closing down elevators. The number of elevators will be reduced from 92 to approximately 15 after harvest of 2007. The objective of Blåljus is to increase the price of grain with 10 öre/kg. A project has been initiated at the Lantmännen Grain division where the purpose is to provide the farmers with support in their decisions and practical advice how they can load a 35 ton grain truck on 30 minutes. The result from the project will serve as a support system to the farmer in his ambition to achieve cost efficient systems to load a truck with grain on the farm.
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.
Ytbehandling baserad på hampolja
The varieties of paint are today very big, but many of the more popular paints are less than environmental friendly. The uses of fossilized fuel in paints are common because these paints dry fast and are color true. It would be beneficial for the environment if more renewable source were used to produce paint. Linseed oil is an old base for oil paints. It is renewable and easily procured.
Energy efficient storage of biomass at Vattenfall heat and power plants
Storage of biomass is often associated with problems such as heat development, dry
matter losses and reduction of fuel quality. The rise in temperature can potentially
cause a risk of self-ignition in the fuel storage. Moreover, emissions from storage piles
can cause health problems in the surrounding. The dry matter losses and reduction of
fuel quality can have economical effects. The aim of this thesis project is to develop
guidelines on how to store large amount of biomass at Vattenfalls heat and power
plants in an optimal way.
Axial- och gradientkrympning hos golv på mark enligt Eurokod 2 : Sprickbredders beroende av betongkvalité, tvångseffekter och armeringshalt
AbstractConcrete foundation slabs are usually exposed to unilateral drying during the curing process. The unilateral drying causes an axial shrinkage and a concave curvature of the construction. The curvature results from the fact that the upper part of the slab is drying and shrinking faster than the lower part. This is called gradient shrinkage.A problem occurs when the slab is considered fully restrained by adjoining structural parts. The deformations caused by axial contraction due to the constant part of the shrinkage and the curvature caused by gradient shrinkage of the slab are then prevented by the fact that the slab is fully restrained.
Uttorkningsmöjligheter i ett fuktskadat badrum med hjälp av spaltmetoden
Buildings today are built to maintain a healthy indoor environment and an efficient energy usage which is probably why damages caused by dampness has increased since the 1960?s.A study between year 2008 and 2010 showed that 26 percent of the 110 000 examined houses had damages and flaws caused by dampness that could prove to be harmful later on. This means that one out of four bathrooms risk the chance to develop damages by dampness. Approximately 2 percent of the houses had already developed water damages. It is here where the problems appear.
Hygienisering av torkat bioavfall
The main project Dry preservation of food waste from households includes a new technique concerning drying and storage of dried biowaste as well as a study of the sorting of household waste and further usage of the dried biowaste. A question asked in the project is, can the dried biowaste be used as a soil amendment? If organic waste is used as a soil amendment, precaution concerning hygienic safety risks has to be accounted for. The objective of this M. Sc.
Avblås för torkning av kabel
This report is written on the assignment by Nexans IKO Sweden AB in Grimsås which is a cable manufacturing company. Nexans IKO Sweden AB was in need of help to examine possibilities for saving energy by saving compressed air, in first place by using the compressed air more efficient. The task was to determine the present situation, making the airwipe stations more efficient by reducing the consumption of the compressed air and in turn save money. Even the aspects of the working environment were discussed as the noise levels from the pneumatic systems and engines are usually high. A schedule over the airflow in the factory and the inventory over current airwipessituation was made.