The last decade has created an increasing pressure on companies to decrease their impact on the environment and to increase their effectiveness of recycling the company?s resources, especially for the steel industry. Companies have also started to realize the economic aspects of an effective internal reverse logistics. In the past the value of an effective internal reverse logistic was something that companies tend to underestimate and there are few academic studies done in this area. The purpose of this essay has been to identify key factors to create an effective in plant storage, transport, sorting and handling of returned steel. From these factors a generalized model for creating an effective return steel flow will be developed.

This bachelor?s degree thesis was conducted in mechanical engineering at Halmstad University during spring semester 2010 in close collaboration with the company Gremo AB, located in Ätran, Sweden. Gremo AB produces, developes and sales forest machines in both Sweden and on the international market.Gremo AB belongs to one of the market leaders in forest industry, especially with their forwarder. In order to become a market leader even with their harvester, the company decided to change the harvester to have a swivel and a leveling driver cabin.The aim with this bachelor?s degree thesis was to develop a design concept for the harvester driver cabin, which Gremo AB can apply on the new harvester.

A problem in the field of district heating is the oil burners needed to provide power when a peak load occurs. One possible way of reducing the needed amount of oil is to reduce the power demand for space heating in the district-heating substations when the need for district heating water exceeds a certain limit. This can be done by use of a locally working controller function.In this Thesis the options concerning load priority are evaluated. To evaluate the potential for using controller functions concerning peak load priority an experiment was brought out in a chosen district-heating substation. The impact on the indoor thermal comfort during a heat reduction was also taken into account.

This bachelor?s degree thesis was conducted in mechanical engineering at Halmstad University during spring semester 2010 in close collaboration with the company Gremo AB, located in Ätran, Sweden. Gremo AB produces, developes and sales forest machines in both Sweden and on the international market.Gremo AB belongs to one of the market leaders in forest industry, especially with their forwarder. In order to become a market leader even with their harvester, the company decided to change the harvester to have a swivel and a leveling driver cabin.The aim with this bachelor?s degree thesis was to develop a design concept for the harvester driver cabin, which Gremo AB can apply on the new harvester.

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.

Two elementary schools are now being built in Gråbo (in the municipality of Lerum),Röselidsskolan and Ljungviksskolan, which are both designed with solar thermalcollectors for the schools domestic water heating. During the summer while thelargest amount of solar heat can be generated, the activity hence the domestic wateruse in the schools are heavily reduced. Both schools are connected to the local districtheating system which makes it possible to use the solar collectors to deliver heat tothe district heating.The purpose of this thesis is to evaluate the two systems mentioned above and todetermine which system is more suitable to apply on a school. The building whichconditions were used for this evaluation is Röselidsskolan.A solar heating plant of each system type was dimensioned from the expected andknown conditions of the building. The purpose with the dimensioning was to makethe solar plants replace the ordinary energy source as much as possible.

When grains of wheat and rye are conventionally milled, large quantities of bran classified as by-products are left and are mainly used for animal feed. Bran is a complex material composed of the aleurone layer, nucellar epidermis, a seed coat, a fruit coat and a small proportion of the germ and endosperm depending on extraction rate. The bran fraction consists of approximately 40-50 % dietary fibre which can contribute to increase the nutritional quality of human cereal food. It would also be valuable for the food industry to convert by-products as bran to products with higher commercial values. The aim of this thesis was to analyse the content and composition of dietary fibre of heat treated wheat and rye bran according to the Uppsala method with some modifications in order to analyse soluble and insoluble dietary fibre separately. Half of the bran samples were precooked, dried and roasted and the other half dried and roasted (uncooked).

This pre-study investigates the possibility of U-value measurements through an acoustic method. A hypothesis about an acoustic model built on acoustic theories combined with U-value theories is presented to answer the questions: ? Can U-value theory be combined with acoustic theories? ? Can the coefficient of heat be affirmed trough an acoustic measurement? The idea for this dissertation begun with a logical idea in mathematical similarity, between the coefficient of heat transmission units and sound intensity units. The U-value theory is based on assumptions such as initial resistance for inner walls and initial resistance for outer walls. The resistance in the material is interpreted through sound intensity theory. The argument is built upon mass law theory, which means if the frequency or thickness of the material layer doubles it implies an increase of sound reduction by 6 dB.

This thesis has identified and studied measures to allow for reduced use of electricity in a waste incineration plant in western Sweden. The energy extracted from the waste at the powerplant is utilized and sold in form of electricity and heat. Technical and environmentally the combined heat and power plant is by today's standards among the leading waste incineration plants in the world. The owners are constantly striving to improve the efficiency of the waste incineration plant. They have seen the opportunities for savings in reducing internal usage of electricity.

Heat is distributed to the district heating customers through pipes with water as a heat carrier. The district heating system is complex. To decide what is leakages from the district heating net versus what is the water consumption of the plant, is difficult. Therefore, the purpose of this master thesis is to establish a model where the district heating net?s leakages but also the water consumption of the plant can be followed daily. The project is performed at Vattenfall´s district heating power plant in Uppsala. Information is gathered through discussions, drawings of the plant and guided tours of the plant.

This bachelor?s degree thesis was conducted in mechanical engineering at Halmstad University during spring semester 2010 in close collaboration with the company Gremo AB, located in Ätran, Sweden. Gremo AB produces, developes and sales forest machines in both Sweden and on the international market.Gremo AB belongs to one of the market leaders in forest industry, especially with their forwarder. In order to become a market leader even with their harvester, the company decided to change the harvester to have a swivel and a leveling driver cabin.The aim with this bachelor?s degree thesis was to develop a design concept for the harvester driver cabin, which Gremo AB can apply on the new harvester.

The aim of this study was to investigate how seasonal variations affect the quality of logging residues. The study was hosted by VIDA Energy. Logging residues can be processed and transported within different systems. Today the dominant systems are chipping at landing and bulk transportation of logging residues. In these systems the handling of the logging residues are carried out in the same manner up to the landings. Moisture content at the time of chipping is the primary quality parameter. Fine fractions of logging residues are strongly dependent on moisture content in storage.

The report comprises two separate parts:part 1:  Temperature needs for district heating in the paint shop for axles in building 210part 2:  Energy and low temperature waste heat solutions in heating and cooling systems for   building 64 with surroundingsThe paint shop for axles in part 1 has air quality requirements in places for coating of axles. Toachieve desired air properties there are different process ventilation systems, which consist ofventilation coils for heating and cooling, plus air humidifier. The ventilations coils for heating usedistrict heating. Today the ventilation coils use water of 100°C to achieve necessary air demands inthe coating boxes. This part of the report investigates whether the existing system would achievethe air requirements with a water temperature of 75°C instead of 100°C in the ventilation coilsduring the coldest parts of the year.

The New National Elevation Model (NNH) is a new high-resolution digital elevation model (DEM) of Sweden from airborne laser scanning. It creates many new opportunities, particularly in the area of flood mapping. NNH is provided by Lantmäteriet in two formats, both in raw LIDAR (Light Detection and Ranging) data and in grid format with two meter resolution. These alternatives have advantages and disadvantages and the aim of this thesis research is to identify these. One of the focuses of the study is data storage and thus data structure analysis, resolution and storage facilities. The research questions are:Why and in what context the different NNH-products from the National Land Survey are used (DEM 2+ or point cloud)?What constraints and opportunities are created by the different options, mainly in terms of different software, resolution, and data storage?The study area is Kärsön in Ekerö municipality located in Stockholms län and has an approximate area of 25 square kilometers. The study is divided into two parts. The first objective is to identify the consequences of using different software to create DEM from pointcloud compared to the DEM2+ model. Height models with a two meter resolution are created in FME and ArcGIS. The models are then compared with the grid from Lantmäteriet, created in TerraScan. The second objective is to examine the impact of the change in resolution, both the storage aspect and both the accuracy aspect. Inverse Distance Weighted (IDW) is an interpolation method which in previous studies proved to have the best results on high resolution LIDAR data. This model was tested and compared with a model from FMEs built-in function and the model from Lantmäteriet wich are based on triangulation (also proved a good method in previous studies). The grid created in TerraScan has good properties such as accuracy.

Preservation of cells and tissues by freezing at temperatures below 70°C has led to new possibilities for the storage of germ cells for fertility preservation. During the freezing process problems might occur, the greatest being ice crystallization which can cause membrane destruction and thus cell death. To minimize this risk, solutions that reduce the freezing point can be added to reduce crystallization and increase survival rates. These solutions are called cryoprotectants. The best method for freezing is still not known.The aim of this study was to analyze the effect of various parameters on the survival rate of human semen frozen with liquid nitrogen.