The cat has evolutionary become an obligate carnivore. Today it is common to feed the cat a dry food. Studies have shown that the dry formula can have negative consequences for the cat. A literature study where conducted to investigate whether the cats origin makes it incapable to compensate for the changes a dry food entails. The impact and implications regarding water intake, energy intake and blood glucose concentration when feeding the cat dry food where examined.

The aim of this thesis was to examine if it is possible to keep nitrogen in the form of nitrate(NO3-) in ponds from one season to another by keeping a high concentration of oxygen in thepond water. This hypothesis was tested by doing a lab experiment where two systems werecompared according to nitrate concentration. One system had high concentration of oxygen inthe water and one had low concentration of oxygen. Before the main experiment wasconducted I did a pilot study to test the system setup and included parameters. The result fromthis study and the main study did not show the same result.

This thesis is performed in cooperation with Prodelox AB and JTI (Swedish Institute of Agricultural and Environmental Engineering). The purpose of the project is to generate and develop a WC-technique with a closet sewer that keeps a higher TS-substance than 1.5 %. The WC-technique is mainly directed towards permanent households in sparsely-populated areas and cabins. The goal is to generate concepts of toilets with an extremely low use of water in terms of flushing. The design should be appealing and touch more senses than only the visual.

Uppsats för avläggande av filosofie kandidatexamen i Kulturvård, Landskapsvårdens hantverk, 15 hp [2015].

Vatten är en av jordens livsviktiga resurser, en resurs som hela tiden minskar. I delar av världen råder akut vattenbrist och ofta återfinns industrier med hög vattenanvändning i områden med begränsad vattentillgång. En av dessa industrier är textilindustrin. Vid textil beredning är vattenförbrukningen mycket hög och avloppsvattnet är ofta mycket förorenat. Vattenfrågorna inom textil produktion har fram till idag inte uppmärksammats i lika stor grad som arbetsrätts- och kemikaliefrågorna.

Swedish government aid is divided into three main themes: democracy and human rights, the environment and climate, and gender equality and women's role in development. These three themes in aid are considered by the government to be vital in order to fight poverty and create fair and sustainable development. This study will examine two of the four focus areas designated under the theme of "environment and climate". The study observes the relationship between projects in energy and water and how it promotes a sustainable lifestyle. A survey on environmental habits will be conducted.

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.

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.

Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants.In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion.

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.

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.