Biogas is a renewable energy produced through anaerobic digestion, which means that organic matter is degraded by microorganisms under anaerobic conditions. The produced biogas can then be used for cogeneration, electricity, heat or upgraded to vehicle gas. Eskilstuna Energy & Environment AB has four digesters at Ekeby water sewage treatment plant, Eskilstuna. One of the biogas reactor (RK4) is equipped with a jet-mixing system while the remaining digester uses top-mixing. The mixing system is an important parameter to achieve optimum operating conditions for the process regarding gas production and degree of digestion.

Scandinavian Biogas is involved in the planning of a combined ethanol and biogas factory in Karlskoga, Sweden. Besides biogas and ethanol large amounts of digester residues will be produced, about 450 000 liquid tonnes residue (~7,3 % Dry Substance( DS)). The objective of this thesis was to investigate possible uses of the residue from the biogas production process ScandgasEthanol developed by Scandinavian Biogas, and to derive a methodological approach how to evaluate and compare handling systems. Three systems where proposed and compared in this thesis; spreading of the untreated residue as fertilizer (system 1), dewatering to a higher DS content to reduce transportation before spreading as fertilizer (system 2) and production of a solid fuel by dewatering and drying the residue (system 3). The general conditions for the proposed systems were investigated in terms of practical viability, economical aspects, environmental impact and energy inputs/outputs.

Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon habitats also contribute to coastal carbon sink capacity.

Mussel meal is a potential source of protein, with a good composition of amino acids, for laying hens and broiler chickens, and may replace the use of fish meal in organic poultry production. Lead and cadmium are heavy metals which occur in the environment and can be accumulated in mussels. When poultry are exposed to heavy metals, the metals are absorbed in the small intestine and distributed in the body in the form of ions, complexes or bound to proteins. In poultry, lead accumulates in bone tissue, liver and kidneys, while cadmium accumulates in liver and kidneys. Generally very low concentrations of these heavy metals occur in muscles of broilers which have been exposed to feed contaminated with cadmium or lead.

The background of this work is the media discussion about the effect of cultivation on peatsoils on greenhouse gas emissions. It has been argued that row sown and intensivelycultivated crops such as carrots are more likely to emit carbon dioxide than for example grassleys. The association KRAV (an association promoting organic farming) shall, from this yearadapt their environmental policy to be more climate smart and have asked the question if thecultivation of some crops is more climate smart than others? Carbon dioxide emissions fromsoil are due to degradation of organic material and the rate is controlled by microbial activity.The microbial activity is determined by a variety of factors such as temperature, soil organicmatter quality and water content. I have measured the carbon dioxide emission from fourdifferent crops at two different farms.

This report that is written in cooperation with Peab Sverige AB, studies the information and knowledge management from the production support to the production management. The conclusion of this report is that to have a good and functional information and knowledge management it is necessary that the company has a good way of regain and handling experiences from its projects. The way to do this is to develop the managing system on the production management?s terms. It is also critical to find an easy way for the production management to use the system..

A large part of the time losses in production in modern manufacturing industry are a cause of unplanned interruptions in production. In this essay we have studied the effects of an unplanned interruption in production. The study was performed during one month on a press production line at Volvo Cars Body Components (VCBC) in Olofström. The effects of the interruptions have been studied on the basis of two perspectives of the environment of the production. The study started at the level of automation and was mainly done as a survey of the unplanned interruptions in production.

Mine waste from Ljusnarsbergsfältet in Kopparberg, Sweden, is considered to constitute a great risk for human health and the surrounding environment. Some of the waste rock consists of sulphide minerals. When sulphide minerals come into contact with dissolved oxygen and precipitation, oxidation may occur resulting in acid mine drainage (AMD) and the release of heavy metals. The purpose of this study has been to characterise the waste material and try to chemically stabilize the waste rock with a mixture of sewage sludge and calcium carbonate. The drawback of using organic matter is the risk that dissolved organic matter can act as a complexing agent for heavy metals and in this way increase their mobility.

ABB Capacitors is looking to introduce LEAN within their organization. The purpose of this research is to suggest ways to improve the production planning in order to facilitate the company?s production processes. This should be done in accordance with the LEAN concept.Today, ABB will produce two of the customers? orders at the same time.

The purpose of this study is to investigate how much of the estimated annual electric energy production from Swedish wind power that actually was produced, as well as the history of this agreement over time. The aim is to also examine if there are properties that have caused some group of wind power plants to produce more or less, compared to their estimated production. Operational data on wind turbines collected by the Swedish Energy Agency was analyzed. A survey was made among owners of wind power plants with a nominal power of at least 2 MW. Two different methods for normal year correction of production data were used and compared.

The demand for district heating is expected to decrease in the future, due to competition from heat pumps and energy efficiency measures in buildings. Development of existing district heating systems is therefore necessary for district heating companies to maintain market shares. This Master?s thesis describes and investigates the heat and electricity production and profitability of a combined Organic Rankine Cycle (ORC) and heat pump that is integrated with an existing district heating system. The studied district heating system is utilizing heat from waste incineration. In Sweden waste constitute 20 % of the fuel mix used in district heating systems, and this share is expected to increase in the future.

The report is about efficiency of a current production group where there is no clear production flow and there are some buffers between the operations. The efficiency is done with the help of a tool that is calledWork process of flow production which is used by Atlas Copco CTO. The most obviously results are that the lead time drops from 25 hours to 425 minutes and that the balancing loss decreases from 85 % to 8 %. The report focus on decreasing transports, decreasing buffers, more reliability in lead time and quality. And a more stimulating labour content for the workers is another result..

The demands for higher production yields and better quality materials from the forests are increasing globally. Tree breeding programs are directed to meet the future demands on forests. In order to capture the full benefits from the breeding programs, clonal propagation is necessary. For most conifer species, somatic embryogenesis (SE) is the only available option for large scale clonal propagation of Elite clonal material. For Norway spruce (Picea abies L.

Magnesium is an essential mineral that is important for several physiologic and biochemical processes in the body. Deficiency of magnesium is mainly associated with grass tetany, but can also appear in cows during the indoor period. Since long it is known that potassium has a negative effect on the absorption of magnesium. Due to the fact that potassium fertilisation leads to a higher potassium content in forage, it is of interest to study interactions of potassium on the magnesium balance in dairy cows. There are few studies about magnesium feeding to dairy cows in Sweden and the purpose of this study was to investigate how much magnesium and from which feed-sources dairy cows in Sweden get their magnesium. Data was collected from seven farms in the northern part of Uppland and from seven farms in Skaraborg in Sweden.

In a sustainable society the use of renewable energy and recycling of materials is of high importance. Wastewater treatment plants use large amounts of energy in the processing of wastewater. This study seeks to evaluate wastewater as an energy resource and to examine treatment plants potential to become sustainable energy producers. The study is based upon the internal processes of Himmerfja?rdsverket.