Climate changing is a growing problem for many countries and communities over the world. The cities has a huge work to deal with in their reforcements of their cities to be resilient ones. This thesis makes an effort to investigate and illuminate some of the problem the cities has to solve related to flooding, hazards, erosions, rising sea levels and crotches. This thesis will help to find solutions that international and national efforts has produced and handed out to each other. A lot of communities are charing their excellent tools that works for them.

Earlier investigations showed that damages on timber from feeding rolls could be within the lower classes of damage according to VMRs classes. Knowledge about differences in productivity between kind types and aggressive types of feeding rolls is necessary because it should influence the question about damages on timber caused by different feeding rolls. In this study the production and timber damage in a harvesting head were evaluated at three levels of pressure (8, 10 and 14 MPa) on the feeding rolls, and with three different types of rolls. One type, the rubber cushioned steel plate roller had 10 mm studs and rubber damping, one ?middle? type made of solid steel with 14 mm studs, and one aggressive type, also made of solid steel with 18 mm studs.

Arvika Fjärrvärme AB, a district heating company from Arvika, today cover 74 % of their total energy production with biofuel wich runs a 16 MW bioler giving process water at saturated liquid state.In recent years Vaporel AB has introduced a new tecnique that gives an external generation of steam after boilers. The concept is built on an adiabatic pressure drop of the saturated liquid in a so called Flashbox which makes a small part of the liquid to evaporate. The generated steam is lead into a turbine where electricity is in a conventional manner.The purpose with this rapport was to do a basic study for the specific system at Arvika where it?s possible to see the potential production of electricity that follows an installation of a flasbox.The final goal was to introduce an economic analysis of a flashox installation at given conditions.To reach our goals we have created a model in Excel where we used the given conditions at Arvika Fjärrvärme to do our calculations. The model has been tested at three different states, of process water returning to potboiler, to be able to decide the optimal operation for the system at present.The studies have resulted in a pressure of the processwater at 14,5 bar (at) and a pressuredrop to 9,5 bar (at) in the flashbox.

Pharmaceuticals that are found in marine ecosystems are a threatening environmental concern, which is known to harm both animal and plant life. One of the reasons for this problem is that the waste water treatment techniques are not optimized to clear waste water from its pharmaceuticals contain. In this master thesis four Swedish treatment wetlands were studied, and their ability to reduce numerous pharmaceuticals in waste water. The four treatment wetlands that were studied were those in Oxelösund, Trosa, Nynäshamn and Eskilstuna. Two ecotoxicological tests and chemical analysis were used.

In times of increased flooding, enhanced by climate change, polluted stormwater poses an increased threat to the environment through contaminated water entering waterways. Bioretention utilizes natural processes in soil and vegetation to treat pollutants and combat this threat. Biochar produced through pyrolysis, has a high cation exchange capacity (CEC) and could therefore increase treatment in bioretention systems. This research applies a literature review, interview, and a model to explore the benefits and disadvantages of biochar in order to specify a soil-mix through an understanding of the production process and preferred application rate. High purification through CEC, increased water holding capacity, and carbon sequestration being the benefits discussed.

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.

This thesis investigates techniques for stealth hydroacoustic communication using spread spectrum. The Swedish naval defense organisations have a vision that all their units should be able to communicate with each other, even between underwater vehicles. But the properties of water makes it a complex channel to use for wireless communications. Radiomagnetic waves have very limited range in water, therefore acoustic waves are used. In this report the basics of wireless communication systems are described including source coding, channel coding, modulation techniques as well as different techniques for spread spectrum.

Freshwater environments are threatened worldwide, of which many of the species associatedwith freshwater. In 2014, 243 freshwater mussels were on the international Red List. One ofthem is the freshwater pearl mussel, Margaritifera margaritifera, which because of itscomplex life cycle can be counted as an indicator of whether a stream is worth protecting. It's since the early 1900's in decline throughout their range. Sweden is counted as a core area which is why we have not only a national but an international responsibility to conserve the species.

One of the environmental problems today in seas, lakes and streams is eutrophication. This is often caused by nutrients such as phosphorus (P) and nitrogen (N) that leak from agricultural areas. A measure to partly prevent the nutrient discharge is to construct or restore wetlands.In order to control the efficiency of nutrient reduction of existing wetlands in the county, the administrative board in Västra Götaland wants to find different criterias for reference wetlands. These reference wetlands should represent other wetlands and be used in future evaluations of reduction of nutrients and design of constructed wetlands. According to the administrative board in Västra Götaland the reference wetlands should have a catchment area of about 50 hectare consisting of at least 70 % arable land, to represent wetlands created to remove nutrients.

Sapa Heat Transfer is a company that produces aluminum heat-exchanger strips for the automotive industry. Sapa Heat Transfer wish to chart their emissions of carbon dioxide in order to meet future demands on carbon dioxide reporting. They also would like to examine the meaning of the term ?green electricity? which is marketed as carbon dioxide free, and the sort of electricity that they purchase. This report includes both direct (liquefied petroleum gas and diesel) and indirect (water, process-water, long distance heating, waste) emissions from their company.

The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.

ABSTRACTMany wind turbines have problems with icing and there is still no effective method to de-ice without stoppage of production and power loss. Here I therefore consider other methods than those available today, and particularly, I consider how these methods could be applied to wind turbines of the company Oxel. A surface where the water droplets do not attach might be the basis for a useful method. If no water attaches, no ice could form. To accomplish this a hydrophobic surface is nessesary, for example wax.

In this study we try to focus on the costs for wear parts on different type of soil tillage machines and at Väderstad Rapid drilling machine. We have studied some of the leading types of cultivators and disk harrows. Among the cultivators we have investigated Väderstad Cultus, Dalbo Dinkomax, Horsch Tiger and Terrano. At disk harrow we have looked at Amazone Catros and Väderstad Carrier. We have made more detailed study on costs for wear parts, working depth, driving speed and diesel consumption.

We are heading towards a huge switch of how energy is produced with fossil fuels being replaced by renewable energy sources. It is not difficult to replace the energy you use in the house and there is no need for futuristic technology. There are already many established products on the market such as high efficiency vacuum solar collectors, heat pumps & small wind power stations that can supply the energy being used in a house. The company Sol & Energiteknik SE AB in Huskvarna has many different products which can reduce the need for an outside energy distributor. An average house in Sweden uses 15 000 kWh for heating, 5000 kWh for tap water and 5000 kWh for electricity.

The estate of Rämningstorp in the region of Västergötland in southern Sweden is administered by the holding trust company Skogssällskapet i Skövde. In 1999 measures were taken by Skogssällskapet to drain the stream Fredstorpsbäcken as a means to increase the forest productivity of the surrounding lands, which are situated on the estate of Rämningstorp. Almost immediately after the drainage, the streamwater turned turbid and a landowner downstream reported the issue to the county administrative board of the region. The aim of this thesis was firstly to analyse the suspended matter that appeared during summer/autumn and secondly to explain why it came to be. Initial hypotheses for the explanation to the greyish turbid water were that it was either 1) a chemical/biochemical precipitate, or 2) an bacterial/algal blooming.