The purpose of the project has been to work out recommendations that reduce the energy-related costs and environmental impact of HPW Fresh & Dry Ltd., a fruit drying factory in Ghana. The factory produces electricity with diesel and biogas but also purchases electricity from the national electricity company. Heat for the drying process is produced from biogas, kerosene and solar panels. In the project the energy system was analyzed by measuring production and consumption of heat and electricity. The project results show that the factory can become self-sufficient on heat if the available energy is used more efficient. The production units for both electricity and heat have low efficiencies.

Today cultivation of cereal in Sweden has high costs for establishment in relation to the rest of the world, and if this cultivation will be able to continue, the farmers have to control their costs. It is important to see all costs, not the maximum harvest achieved, but the net result. All farmers have different conditions with respect to soil, direction of the farm and were the farm is located geographically. With the right knowledge and ambitions, we think most farmers could change to reduced tillage. In this paper we have tried to find out if reduced tillage is an alternative for farmers.

Through previous studies during my education, I have experienced that chemical deicing road salt is a known problem, mainly in southern Sweden. Road salt causes damage to the environment and also damage to vehicles and structures such as bridges, etc. Road salt causes vehicles and steel constructions to rust, leading to increased costs for repairs of damage to structures. Road salt also causes damage to the plants and the economy to suffer, when plant material and soil needs to be replaced. In order to get closer to a solution, I put up three questions.

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.

Den här rapporten är ett resultat av ett examensarbete i ämnet maskinteknik med inriktning bistånd genomfört vårterminen 2010. Arbetet är ett samarbete med den svenska organisationen Ankarstiftelsen, som har bistått studenterna med kontakter i Leticia, Colombia.Arbetet har varit förlagt dels i Sverige och dels i Leticia, Colombia och har bestått av en förstudie i Leticia samt en litteraturstudie. Målet med arbetet har varit att ta fram ett förslag på lämplig placering och val av turbinsystem, utifrån de förutsättningar som finns i området.Rapporten presenterar olika metoder för elproduktion i Amazonasregionen, turbinsystem anpassade för strömmandevattenkraft och resultat från förstudien.Rapporten presenterar ett förslag där en turbin av modellen Darrieus installeras på en ponton vid samhället Milagrosa. Turbinen beräknas i dagsläget täcka det elbehov som finns i samhället. Dock kvarstår finansieringsfrågan..

Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.

Coastal sediments are important carbon sinks, storing organic matter and thereby helping to reduce the amount of greenhouse gases in the atmosphere. However, they can also act as carbon sources if the deposited organic matter decomposes rapidly, contributing to increased greenhouse gas emissions and global warming. Rapid decomposition partly depends on the degradability of the material itself. In this literature review, I examine which coastal plant species dominate different locations along the Swedish coast, based on coverage data from the ClimScape project (www.climscape.se). For the most dominant species, I investigated the type of organic matter they may contribute to the sediments and based on those results I qualitatively assessed which sites that may function as carbon sinks or sources.

The purpose of this thesis has been to assess whether leaching from one particular Swedishlandfill site, Skörbytippen, is contributing to elevated levels of heavy metals in a ditch runningfrom the landfill site to the lake Mälaren in the communal region of Håbo kommun. Since theditch is stretching approximately five km downstream from the landfill site, in situ observationsand maps with known points of inflow was utilized to determine appropriate test points for thecollection of samples.Soil, water and sediment samples were collected and analyzed for content of organic material, pHand conductivity. Data on plant-available elements and total amounts of heavy metals wasacquired through ICP-analysis.The results show that the Skörby landfill is currently in the methane-forming anaerobedevelopment phase, which indicates that the concentration of free and complex-bound metals inthe leachate water should be low due to chemical binding with other landfill compounds. The pHof the sediment samples was generally one unit higher than the soil samples and some of themeasured data, such as pH and conductivity, show that an environmentally disturbing dischargeof some kind of strongly alkaline chemical(s) has been made from Benders? takpanneindustri inclose proximity to the landfill.

Our purpose in this paper is to examine if there is any profitability for a company with a factory in the timber industry to invest in a combined heat and power, CHP. Based on analysis and the results that the paper generates, we will give Derome AB a suggestion on how it is a profitable investment or not to installing in a CHP.By investing in a CHP plant, you can get a high efficiency, which means that companies can use their resources more effectively. The Swedish wood industry has by-products of production that can be used for combustion in their boiler which is an advantage.The essay is a qualitative study where we have a case company, Derome AB. In this company, we interviewed two employees who have knowledge in the study. They have helped us to provide information and data about their business.We chose to use the pay-off- and the net present value method, NPV, to see if there are profitable advantages for the investment.

There are around 855 000 on-site sewage systems in Sweden and some 1 800 of these are located in the municipality of Sigtuna. The Sigtuna local authority has set the goal that all sewage systems with insufficient function should be improved before the end of year 2010. A malfunctioning on-site sewage system may cause three main problems: spreading of diseases, discharge of eutrophicating compounds and wastage of resources. The municipality strives to reduce these problems already at the stage of granting permits for installation of on site sanitation systems. The municipality has recently adopted new guidelines, which demands certain minimum reductions for different compounds. The guidelines also state that it is preferred that neighboring house-owners cooperate in jointly built and operated sewage systems and that the system should be able to recycle plant nutrients.

The aim of this study was to in laboratory experiments investigate how addition of urea, ECOX and structural materials can optimize sanitization during composting of sewage sludge. Today we strive for a sustainable society and the importance of closing the nutrient loop increases. It has therefore become even more important to safely reuse plant nutrients from human excreta to agricultural land. Partly because it increases the sustainability of society as the world's supply of many nutrients are finite, partly because it promotes human health, both by reducing disease transmission and by increasing Agricultural production. An untapped resource such as sewage sludge that is rich in nutrients and humus-forming materials could replace parts of the commercial fertilizers used in Sweden today. owever, sewage sludge contains undesirable substances such as heavy metals and drug residues, and pathogenic microorganisms.

Emission of nitrogen oxides as well as carbon monoxides is an inevitable result of combustion. A Swedish law "Law of environmental fee for emissions of nitrogen oxides as a result of energy production" (lagen om miljöavgift på utsläpp av kväveoxider vid energiproduktion (SFS 1990:613)) controls the emission of NOx from energy production by a system of fees. The system has resulted in a strong approach toward less emissions of NOx among the energy production plants. High emission levels, today exceeding 52 mg/MJsupplied fuel, leads to costs for energy production companies. This paper examines possibilities to reduce the emissions of NOx by optimization of the SNCR-technique in a biofuel fired heat and power plant.

Given that the oil prices have risen and the environmental regulations has become more stringent, the interest in operating efficiency has increased. The project has investigated the possibility of producing electricity from waste heat generated in the diesel process. One technique to utilize and convert energy into electricity is the ORC (Organic Rankine Cycle). This process is based on the Rankine process (the steam process), the difference from the traditional Rankine process is that instead of water as a working medium, an organic substance is used. The main component used in the process is a evaporator, a turbine, a condenser and a pump.

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.

In order to facilitate design and maintenance of such a large and complex site as a nuclear power plant, all system functions must be described in a stringent way. In the past, these descriptions consisted of text documents and logical diagrams, but today there are an increasing number of object-oriented programs available on the market which might be used for this purpose. This Master Thesis has made a closer study of one of these programs named Rational Rose. The principal of the program is to facilitate software design and development, not to create models of plants. However, using the program the same way as developing software, specifying actors then gradually extend the model with use cases, use cases diagrams etc, the same methods can be used when modelling plants.