The production of ferrochromium alloys at Vargön Alloys AB contributes to formation of unwanted ferrochromium dust, which contains toxic Cr(VI). The dust is since summer 2005 treated with an iron-sulphate solution to reduce Cr(VI) to the non-toxic Cr(III). A year later the treatment technique was improved and disposal occurs in cells on the landfill. The cells can be up to 300 m3 and the edges can be made out of fro example concrete. Tests are conducted on the treated dust when it is disposed.

District heating covers most of the residential areas and industries in the twoneighbouring Swedish municipalities Nyköping and Oxelösund. In Nyköping,Vattenfall AB Värme produces heat in a bio-fuelled CHP plant. In Oxelösund,waste heat and use of waste gases from the steel production at SSABOxelösund is the basis in the district heating system.This report examines the environmental consequences of a connection betweenthe two district heating systems. A broad system approach is used and the focusis on environmental effects in the system.A system analysis has been performed on the result of simulations of differentheat and electricity production alternatives. The alternatives simulated wereone where Vattenfall Nyköping covers the base load in the joint district heatingsystem and two where the power plant at SSAB Oxelösund supplies the heatbase load.The conclusion in this report is that the consequences of connecting the twodistrict heating systems can be both positive and negative, depending onsystem boundaries and on the environmental focus.

The water tower in Uppsala city forest was built in the late 1950's in what is now a nature reserve. The unique place was supposed to be visited by people, which is currently not the situation. This bachelor thesis aimed to perform an analysis and make a design proposal for the environment surrounding the water tower. The analysis was performed using the methodology previously described by architect Arne Branzell. The methodology focuses on how a space is perceived by a person moving through it.

The possibility for plants to utilize phosphorus in soil is a prerequisite for conducting agricultural production, both small scale and professional. Spreading of phosphorus fertilizers and manure is therefore seen as a necessity in today's agriculture in order to achieve high yield. Manure management, livestock farming and manure storage could contribute to the eutrophication of lakes and rivers. For instance, when the ground becomes saturated, phosphorus leakage could be seen in surface runoff or in point sources resulting from inadequate manure storage management.In the municipality of Växjö there is still many bodies of water that do not reach the Swedish environmental water quality standard of "good ecological status". This thesis has therefore analyzed the manure management and storage on agricultural farms which may have contributed to eutrophication in the municipality.The method for this thesis was a literature study, a questionnaire survey with 820 receivers and a summary of issued inspection reports from 2013.The results highlight the ways in which agriculture may have contributed to the eutrophication of lakes and streams in the municipality of Växjö.

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.

In order to avoid harmful substances ending up at the municipal sewage treatment plants, it is important to purify the wastewater at the source. One such source is the wheel washers available in many tire garages which are used to wash the wheels on our vehicles when we change between summer and winter tires. It is important to wash the wheels before storage, to extend the tires lifetime. The purpose of this study is to find a green innovative solution for reduction of emissions of heavy metals at the source, so that the sludge from the sewage treatment plants can be used as fertilizer. The target is to find a wheel wash method which leads to compliance with the guidelines for car washers, and that also provides a better washing result than with the existing method.

This study was made as a part of a feasibility study on a polishing wetland at Rimbo wastewater plant (wwp) in Norrtälje municipality. The wwp had to decrease the nitrogen discharge to reach the limit 15 mg tot-N/l. The nitrogen in the outlet was mainly in the form of nitrate, hence the wetland mainly ought to support denitrification. The proposed area for the wetland was situated right next to the wwp and was already in the municipalitys posession. One aim of this study was to examine what spieces of plants needed to achieve highest possible denitrification.

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.

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.

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.