High levels of ammonia in grass silage have been up for discussion by Swedish advisers. One reason is that it is more difficult for the rumen-microbes to utilise high levels of ammonia. A low level of ammonia is also good because if the cattle can use more of the protein in the silage, they don?t need so much protein concentrate. That is very good for the economy at the farm, and it is also good for the environmental problems caused by high levels of ammonia. In this project, 24 samples of silage have been taken at 20 different farms in the south west of Sweden.

This master thesis project at KTH is performed in the Mechanical and Aerospace Engineeringdepartment at University of Florida (UF). The thesis is a small part of a gas turbine researchproject where a vapour absorption refrigeration system (VARS) and a high pressure regenerativeturbine engine (HPRTE) are integrated together. The main objective is to build a computermodel of the VARS. The computer model is supposed to be used to analyse the off-designperformance of the VARS and should also be easy to integrate as a subroutine in a more complexsystem model. To model the VARS some knowledge of the absorbent/refrigerant mixture had tobe well known, in this case a mixture of ammonia and water.

Bringing back the nutrients from the city to the country is becoming increasingly important, as the world?s stores of nutrients get more exhausted. Sewage sludge is an unapplied resource, rich in plant nutrients, which could replace parts of the commercial fertilizers used in Sweden today. Sewage sludge may contain large amounts of pathogens, such as Campylobacter and Salmonella, why use can cause severe spreading of infections, both to animals and humans. These pathogens have the ability to survive for a long time in soil and water and therefore some sort of treatment of the sludge is recommended before use.

The ammonia emissions are an environmental issue since they contribute to eutrophication. By far the largest source of ammonia emissions is manure from agriculture and should therefore be reduced. Loss of ammonia is not only negative for the environment but also to the farmer who loses nitrogen that could have been used by the crop. The focus of this study has been emissions from spreading slurry where the loss can vary widely depending on slurry-, soil-, and weather conditions. There are mainly two different ways to reduce the emissions. One is to inject or mix the slurry into the ground to avoid air contact. The other way is to use acid to reduce the pH in the slurry to a level between 5 and 6 where the equilibrium is so strongly pushed to NH4+ that hardly any NH3 can be lost.

This report is about the experiments with mixing of the separated water and the vacuum pump seal water at Hellisheiði power plant. This is done to prevent silica scaling and clogging in pipes and reinjection wells as well as eliminating vacuum pump seal water from the plant. The experiments were done in four stages: the first stage comprised of tests with different flows of separated water at 70°C, the second stage was carried out by mixing the separated water at 70°C and the seal water with different amounts of the seal water, the third and the fourth stages were like the first and second but with the separated water at 120°C. The results show that this method is good if the mixture is around 50/50 separated water and seal water, to control the silica scaling in the separated water and to be able to reinject the seal water with the separated water. This does not eliminate the silica scaling in all of the separated water because the amount of separated water is much more than the amount of seal water that comes from the plant. .

We all know that water is very important for both animals and humans. When we are weaning the piglets from the sow we must guarantee that the piglets can start to drink more water instead of sow milk. The first thing to check is always the quality of the water that is to be used. To secure that, you must take a water sample. If the water is inadequate it can bring a lot of problems and diseases.

Water is an important food and an important natural resource. In order to protect these are the Environmental Code and the EU directive given to water protection and related water protection regulations will be established for all water sources until 2010. Those who will prepare a water protection and related water protection regulations is the municipality or person responsible for water supply. The person then decides and declares the area as water protection and related water protection regulations are municipal or provincial government. The idea of creating a water protection is to protect the water supply and the body of water against pollution caused by point sources, diffuse sources and accidents combined.

Emission of nitrogen oxides as well as carbon monoxides is an inevitable result of combustion. A Swedish law "Law of environmental fee for emissions of nitrogen oxides as a result of energy production" (lagen om miljöavgift på utsläpp av kväveoxider vid energiproduktion (SFS 1990:613)) controls the emission of NOx from energy production by a system of fees. The system has resulted in a strong approach toward less emissions of NOx among the energy production plants. High emission levels, today exceeding 52 mg/MJsupplied fuel, leads to costs for energy production companies. This paper examines possibilities to reduce the emissions of NOx by optimization of the SNCR-technique in a biofuel fired heat and power plant.

The aim of this study was to in laboratory experiments investigate how addition of urea, ECOX and structural materials can optimize sanitization during composting of sewage sludge. Today we strive for a sustainable society and the importance of closing the nutrient loop increases. It has therefore become even more important to safely reuse plant nutrients from human excreta to agricultural land. Partly because it increases the sustainability of society as the world's supply of many nutrients are finite, partly because it promotes human health, both by reducing disease transmission and by increasing Agricultural production. An untapped resource such as sewage sludge that is rich in nutrients and humus-forming materials could replace parts of the commercial fertilizers used in Sweden today. owever, sewage sludge contains undesirable substances such as heavy metals and drug residues, and pathogenic microorganisms.

In this literature review the characteristics of two free-floating macrophytes, water hyacinth   (Eichhornia crassipes) and duckweed (Lemna sp.), and two microalgae, Chlorella and Scenedesmus, have been examined regarding their suitability as efficient nutrient removers in the treatment of wastewater with high levels of nutrients and suspended solids from a biogas plant in Loudden. The needs required for the plants to be able to grow in wastewater and the amounts of biomass they can produce have also been studied. The results show that Chlorella is capable of a very high uptake of nutrients in photobioreactors with high nutrient loadings. With an ammonia uptake maximum value at 10900mg/m2/d Chlorella outshines the other organisms in this study. The test organism that performed the closest to Chlorella in terms of nitrogen uptake was water hyacinth with an uptake about 1602mg/m2/d.

The objective of this report was to analyse and compare vulnerability and preparation in Swedish municipal drinking water production, in case the commonly used water sources were inoperative. Methods used were a questionnaire and a less extensive study of regulations for water protection areas. The questionnaire was answered by 41 Swedish municipalities. A handful of them were companies co-owned by a few municipalities. Only one out of four municipalities had source protection areas to all their water sources and for many sources the protection was not satisfactory.

This project is focusing on a future park that will surround Hyllie water tower in the outskirts of Malmö. The water tower will be located in the central part of the new building area Hyllievång. The park will function as a town park with a special focus on water. The water council of the municipality, Va-verket, has for the last 7 years built up and been in charge for a pedagogical programme in the water tower, were schoolchildren come to learn about the cycle of water and how we use water in our daily life. In the park they want to build a new part that gives experience of water, as a compliment to the information in the tower. What will that park look like, and what shall it be constructed of? How do you bring water to the surface in a park? How can landscape architecture work to enhance the presence of water and make people more interested in water issues? In the search to find the answers to all my questions I have meet with people, read books and visited different places.

The purpose of this study was to examine whether urea could be an option as a nitrogen source for young cattle, the study was limited to risks related to feeding, growth and feed efficiency. Microbes in ruminants have the ability to convert nitrogen to protein, this has been highlighted by beef producers as they are in search of cheap protein feed resources. Urea can be a worthy source of nitrogen for growing young animals, because of its high nitrogen content and the low price. Studies have shown that the replacement of a portion of the total protein content by urea in diets with low content of crude protein, like corn silage, may improve animal growth and feed efficiency. Replacement of all the true protein with urea can result in reduced feed intake and microbial growth.

Coastal areas are popular for housing, both for permanent living and holiday houses. At the same time, thin sediments and small storage capacity in the bedrock makes the ground water resources limited. The limited ground water resources combined with too large withdrawals of ground water makes salt water intrusion a problem in many coastal areas. This study examine the risk of salt water intrusion in drinking water supplying wells on the island Södra Finnö in S:t Anna archipelago, Östergötland, Sweden. A calculation of the relation between ground water recharge and withdrawal is obtained to analyze the ground water balance in the area.

The purpose of this study was to examine whether an inventory of the vegetation overgrowth could be used to indicate a locally nutritional impact. The study was conducted at Märstaån where the water runs through a number of agricultural lands that could lead to an increased amount of diffuse emissions of nutrients. The vegetation overgrowth in the water was also studied in relation to shade, meandering and water flow effects on the vegetation. With this method, no definitive conclusions could be drawn.Where the water was shaded, no vegetation overgrowth could be found. Therefor trees should be planted to prevent any future overgrowths.