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.

Due to historically low prices for electricity in Sweden, many small-scale hydropowerplants were closed down. A small-scale power plant has more or less the samemaintenance costs as larger plants, but doesn?t generate as much income. Today?sincreasing price for electricity in combination with a desire for renewable energysources makes small-scale hydropower interesting again.

The main focus for this essay is to describe the relationship between human and nature through a material investigation that takes its shape through sculpture. With the help of a fairytale-like story the reader can share the creation of the sculpture and how my thoughts flow through the process that will result in an exam project. Rooted in earlier projects I discuss the crash between civilization and the wilderness as well as talking about the likeness of the creative process and child play. I also discuss the body's place in the forest and the loneliness that we humans created that has cut us off from the rest of the creatures and plants in the forest. My aim is that in the final piece I will create a fiction place where these can be joined together again.

In this thesis a method for evaluating investments in small scale hydro power is presented. An analysis of the future position that small scale hydro production will have on the Nordic electricity market is also carried out. This is done by an inventory of technology and economic and environmental aspects. The inventory is also a guide as to how the project should be implemented.Hydrolyzer is the name of the Excel tool developed to evaluate investments. The tool requests input data from the user and then evaluates the investment and generates a sensitivity analysis.

This essay examines the grotesque in Samuel Becketts wellknown play Waiting for Godot. The play is primarily seen as an icon of absurdism, and it is such not appropriate to examine the play as if it belongs to the litterary genre of grotesque. The primary purpose of absurdism is to reveal the pointless- and emptiness of existence. In order to illustrate these points absurdism will often make use of the common characteristics of the grotesque. With this in mind I present, within this essay, an eximination of whether Samuel Becket makes use of these characteristics to assist his portayal of emptiness in Waiting for Godot.A prior understanding of absurdism is required and i have as such primarly used Martin Esslins famous studies.The studies of the grotesque are mainly represented by two theorists.

BIOGAS POTENTIAL IN GRASSES FROM WETLANDSMarvin MartinsThe purpose of this study has been to survey wetlands that are suitable for mowing and to analyze the biogas potential in the harvested grasses. A preformed investigation showed that there are suitable wetlands, which can be harvestable, namely those mowed formerly in traditional haymaking. The practice of traditional haymaking is dying out in Sweden today but there are several good reasons why it should to be reconsidered. Nature- and cultural values are obvious, also the unutilized energy in the grass.The suitable types of wetland that were specifically studied were the productive wetlands; meadow marshes and wet meadows. These wetlands are represented in the Swedish meadow- and pasture inventory database; (TUVA) and the Swedish national wetland inventory (VMI).

Several radioactive nuclides were deposited in Sweden after the Chernobyl accident in 1986. The greatest attention was given to 137Cs because of its relative long physical half life of about 30 years. 137Cs will be present in nature for more than 100 years before it has vanished completely. When radiocaesium decays to a stable end product ionizing radiation is emitted, which can cause cancer in humans that has been exposed to a high radiation dose. Radiocaesium behaves like potassium and is easily taken up into biological systems.

Chile and Santiago are struggling with heavy environmental problems as a consequence of urbanisation and industrialisation. In the Santiago region the air is seriously contaminated and most of the rivers are classified as heavily polluted.The aim of this thesis is to survey the industrial fluid waste situation in the Santiago region and to make suggestions on technological improvements or process changes. The purpose is also to study five different enterprises more closely and to give more detailed suggestions for improvement. Another purpose is to summarize relevant Chilean legislation.Information, provided by the supervisory authority, about the release of industrial wastewater to rivers has been analysed. Deep interviews have been made with authorities and consultants.

During the last decades the housing sector has increased continuously, and housings and services accounted for 40 % of the energy usage in Sweden during 2011. The expansion in number of buildings in society has resulted in an increase in both energy usage and emissions of greenhouse gases. It is crucial to enable a sustainable development of society and as a result, the demand to reduce the emissions of carbon dioxide is a current question. In this study, the carbon dioxide emitted from the housing sector in Stockholm is estimated. The housing sector can be divided into different types of houses such as apartment blocks, single-family houses and holiday houses. By collecting information of the energy purchased in respective households, a computational model is generated that calculates the total emission of carbon dioxide.

In this work an assessment of the compressed air system in the facilities of Vattenfall Heat Uppsala has been conducted. The facilities constitutes, among others, a combined heat and power plant, and two waste incineration plants. The compressed air is supplied primarily by seven rotary screw compressors and yearly electric energy consumption in these has been determined. Furthermore, the usage of compressed air has been mapped in order to find processes with energy savings potential. Several suggestions how to reduce the usage of compressed air have been presented, resulting in decreased need of electric energy and reduced CO2-emissions.The results show that total need of electric energy in the compressors, during a standard production year, amounts to 5.83 GWh.

According to the Board of Forestry, in Västerbotten, many natural regenerations of Scots pine (Pinus sylvestris) carried out on privately owned forest in the middle of 1990 in Västerbotten have rendered a bad regeneration outcome and will provide a low future forest production. The Board of Forestry believes that the negative result can be explained by the fact that the regeneration has been carried out in wrong locations and that scarification failed to work as planned. In order for an accepted rate of regeneration the guidelines of the Forrest Act require, not less than 10 years after final cutting at natural regeneration, that there should be at least 1300 (site indices 16 m) - 1700 (site indices 20 m) main crop stems per hectare. Main crop stems are defined as stems according to the place of growth and appropriate tree type, in addition with regard to quality, stage of development and damage risk have a prospect of succeeding. In addition main crop stems should be separated by surface so that the proportion sample plots with 3 meters radius, and lack main crop stems, are not more than 10 % of site indices 14 meters or higher.

Hemp is a versatile plant with many uses that has been around for thousands of years. The plant is highly adaptable andwill cultivate in almost any soil. It has excellent remediation properties and has shown to be relatively consistent when itcomes to crop yields. The aim of this literature survey is to examine how hemp can be used to be considered asustainable energy crop in Sweden through database searches and interviews. Hemps characteristics as an energy cropand its remediation properties is evaluated and compared with other plants that are used in Sweden.

Ocean Thermal Energy Conversion (OTEC) is a technology that utilizes the temperaturedifference in oceans between the warm surface water and the cold water at 1000 m depthto produce electricity. The purpose of this report is to investigate if OTEC with its synergiescould become a commercially feasible energy solution for a small island. A literature reviewis conducted to explore the different OTEC technologies and to what extent the threesynergies; fresh water, air conditioning and aquaculture, could be used. In order to calculatethe profitability of these synergies there is also a study conducted on the conventionalmethods and cost of fresh water production, aquaculture and air conditioning. A model is setup using a scenario of a small tropical Island with population of 100 000 people.

Sammanfattning (English below) Jag har alltid tyckt om naturen och haft en föreställning om att all växtlighet som inte är tydligt anlagd, som en gräsmatta eller en rabatt, är något som naturen åstadkommit av sig själv. Mina ögon öppnades för alternativen när jag för första gången hörde begreppet ?naturlik plantering?. Det här arbetets syfte är att ta reda på hur lik naturen naturlika planteringar egentligen är, om de är planerat naturlika eller något som används som utfyllnad. Syftet är också att ge en indikation på vilken status den naturlika planteringen har. Arbetet består av tre delar. En historisk del som utforskar ursprunget till begreppet ?naturlik?.