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99 Uppsatser om Freeze-drying - Sida 3 av 7
Syntes av hydroxyapatit/ nanocellulosa kompositer
Cellulose nanocrystals (CNC) are great candidates for composite materials. The reasons why CNCs are such attractive materials for them are due to their great mechanical properties, high aspect ratio and low density. On the other hand, hydroxyapatite (HAp) is a kind of calcium phosphate and a main component of bones and teeth. The purpose of the present study is to make oriented nano-sized composites with CNC and HAp. Although some researchers carried out to make CNC composites with HAp for biomedical materials, nano-sized and oriented ones haven?t been achieved yet.
Protein i korn : En torkstudie utförd med etablerade analysmetoder på tre kornsorter
A study was performed to evaluate whether established methods of analysis of protein content in barley (Kjeldahl, Dumas, or NIT (short for Near Infrared Transmittance)) gives different results for wet and dried barley. This was carried out because there are concerns regarding the well-worn NIT prediction model giving different results for these conditions and that such an error causes significant price fluctuations on the market. By performing analyses of samples, both before and after drying, of the three different barley varieties Tipple, Prestige, and Quench, with all the techniques, data was obtained that could be analyzed statistically. The study showed that the NIT prediction model gives results for wet barley that is about 0.29 percentage points higher compared to dried barley. This difference was also statistically significant when a t-test was performed.
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.
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.
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.
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.
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.
Fallstudie : Egen foderberedning till slaktsvin :
The purpose of this examination work was to make a general description about drying and
storage of grain, and a case study with a comparison between brought and home-made feed.
The case study was made on the farm Solhem in Hörby, a farm that produces 3870 pigs for
slaughter a year.
In this project three alternatives have been compared, 1st alternative: own produced grain
approx. 400 ton + wet grain 415 ton purchased during fall, 2nd alternative: own produced
grain approx. 400 ton + dry grain 415 ton purchased during winter, 3rd alternative: bought
feed 815 ton purchased continuously during the year.
Considering the price information provided to me the 1st alternative gave the cheapest feed..
Storjuktan ? Rekonstruktion av ett sekels kvicksilverbelastning. : En undersökning av kvicksilverkoncentrationer i daterat bottensediment.
The aim of this study was to examine the current and historic mercury(Hg) load of the lake Storjuktan due to its recent exposure to a local potential source of Hg in form of the Sulphide mine Blaikengruvan(2006) and an earlier potential sources of Hg-load, the damming of the lake(1960s). Sediments were extracted using a HTH-sampler, freeze-dried, and analyzed for tot-Hg, LOI and activity of 210Pb and compared to samples extracted prior to the opening of the mine(2006). Constant initial concentration (CIC)-dating model was used for dating the samples. Low levels of Hg (100ng/g) were found throughout the lakes sediment. The highest levels of Hg(220ng/g) was detected at a depth of 4-5cm dating back to the mid 1970:s, suggesting that increased levels of atmospheric Hg rather than damming of the lake has caused the increase of Hg.
Torkning och pelletering av organiskt hushållsavfall - en konstruktionslösning
The research in this paper aims to producing a home version machine thatcan dry and make biological waste into compact pellets. This product ismade primarily for those who want to improve the environment and reducethe energy consuming process of separating the biological leftovers fromother waste in the large processing plants and save money due to reducedpickups of waste. Since there is no commercially available product thatdoes what we want to achieve we had to start from the beginning with boththe design and the mechanical aspects. The result is a machine, that fits inour homes, and in an easy and inexpensive way reduces the amount ofbiological waste that needs to be collected by the public wastetransportation system. This is done without reducing any of the energy inthe waste and it can still be used to compost or by large-scale plants that usethe waste to make electricity.
Virkets formförändring och dess betydelse vid postning :
The purpose of this thesis was to create a saw pattern program for the sawmill industry. I have chosen to focus on the module that describes the shrinking on the wood. There are several theories about how the wood deforms by shrinking. Several hypotheses were simulated in the program and after testing them I decided to use only one of them (hypothesis C).
The program is written in Visual Basic .NET and I choused that program language because it
is easy to do changes in the layout. Another great advantage in Visual .Net is that you can mix different languages in the same program.
Prototyputveckling av digitalt styrsystem för torkskåp
Nimo Verken AB is the leading producer in the Scandinavia of drying cabinets. The construction has, with small changes, been the same since the 70s with a thermostat and a timer as controlling system. There was a wish to develop a modern cabinet which showed remaining time on a display and with energy saving functions.In this report we go through how it is possible to implement a digital controlling system, where remaining time is shown on a display and where it is possible to choose a preset ?program?.The report first presents the fundamental theory for a PIC, where we describe the different registers, how interrupts are handled, the internal clock function and how data is sent to control the different parts of the construction.Next the report presents and describes the new hardware that is needed, such as the encoder, the temperature sensor and the display.After the theory we describe how the program in the PIC may be drafted. Last in the report we have the result of the tests of the temperature variations and the accuracy of the time..
Hjärtfrekvensens förändring vid sinläggning av undervisningskor vid institutionen för kliniska vetenskaper :
It?s been noted that cows held at the section of ruminant medicine and epidemiology, Swedish University of Agricultural Sciences (IME), used for the education of veterinary students, have a lower heart rate than what is considered normal for ruminants. In this investigation the heart rates of seven lactating cows were recorded continuously during the period around drying off. The first recording took place at the farm from where the cows were bought, and then their heart rate was monitored after their arrival at IME and further on until they were completely dried off. The results were then compared to the heart rate of seven already dried off cows from the same farm.
Automatisering av spraytorkningsprocess
ABB Surge Arrestors in Ludvika have for a long time had a problem to keep the moisture at a steady state in the production of their ZnO-powder, that is used to produce varistors.Some black-box models of the spray drying process have been designed and evaluated to find a solution for the problem. After evaluating the collected data it has been found that variations in the supply voltage causes control difficulties for the operator. A cascade control system was designed, consisting of three PI control loops designed with lambda tuning. The disturbance in the supply voltagewas used as a feed forward in the control system.At the end of the project the control system was installed, and tests were made to verify the functionality of the regulator. It was shown that most of the variations in the moisture of the powder could be eliminated using small resources, through purchase of a process controller and four power meters.
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.