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2888 Uppsatser om Electricity production - Sida 26 av 193

Biogasanvändning vid Käppalaförbundets Reningsverk: ? en värdering av miljöeffekter

This thesis calculates and compares the values of improved environmental quality due to future possible investment alternatives in biogas production facilities at Käppalaförbundets Reningsverk (Käppala Sewage Treatment Works) in an attempt to determine which alternative yields the highest such value. Käppala faces three investment alternatives for the usage of biogas. The alternatives are production of vehicle fuel, district heating and thirdly, heat and power production. Estimates of the value of environmental change are calculated for each of the three investment alternatives, and these estimates are then compared. The environmental change in question is the change in discharge levels of carbon dioxide (CO2), nitrogen oxides (NOx), sulphur dioxide (SO2) and particle matter.

Effektiviseringspotential inom industrisektorn : Energibesparing vid frekvensstyrning av centrifugalpumpar ? en fallstudie

The project was performed at SiemensIndustry Drive Technologies with theobjective to provide actual values forthe energy savings potential withinSiemens scope of practice.In Sweden the electrical drives standfor about 30 % of the total electricityconsumption and about 60 % of theelectricity consumption within theindustry. During the pre-study phaseelectrical drives with pump applicationswere identified as large energy users.Because of this a case study at one ofSiemens customers, Stora Enso Fors wasperformed. The system that was evaluatedduring the case study was a throttledsystem with a centrifugal pump forpumping pulp.The results yielded that a saving ofover 50 % could be achieved by replacingthe throttle valve with a variable speeddrive, a frequency converter. Thepayback period was two years and twomonths and the present value for thetotal life cycle cost of the variablespeed system was 662.566 SEK lower thanfor the throttled system. As aconsequence, Stora Enso Fors is advisedto invest in a frequency converter forregulation of the system.The general conclusion is that a focuson system efficiency is the mostimportant factor in energy efficiencyprojects and that the system regulationmethod has a large impact on the overallsystem losses and hence its efficiency.Energy efficiency potential forthrottled systems with centrifugal pumpsis large and significant economicalsavings can be made through investmentswith short payback time..

Föryngring i stormfälld rekreationsskog : en jämförelse mellan föryngring i produktions-, rekreation/produktion och rekreationsskog.

When the storm Gudrun hit Sweden on the 8th and 9th of January, many recreational forests in southern Sweden blew down. For this reason there is a demand for new regeneration methods as to how these storm-felled areas should be regenerated and with what species. In this study the forest is divided into three areas: production, recreation/production and recreation. The first area is a forest with production as main goal and these kinds of forests are located a bit from the city. The second type ? recreation/production forest ? has two equal goals: production and recreation, and is located close to the city.

Käppalaverkets nuvarande och framtida rötningskapacitet : en studie i labskala

Käppala wastewater treatment plant situated on the island of Lidingö northeast of Stockholm is running a project during 2004 and 2005 with the purpose to map out the capacity of anaerobic digestion in the digesters that treat primary and excess sludge. The purpose of this thesis work, which is part of that project, was to characterize the present anaerobic digestion process and to investigate its capacity to treat other organic wastes such as restaurant waste and waste from water works. To decide the potential of both methane and biogas production from different substrates batch laboratory tests were carried out. To imitate the anaerobic digestion process at Käppala continuous tests with small scale reactors were carried out. These reactors were later fed with restaurant waste.The batch laboratory tests showed that primary sludge had a potential biogas and methane production of 0,62 and 0,35 Ndm3/g VS respectively after 40 days of digestion.

Resource planning for internal logistics : A tool designed for the material handling department at Scania Axles and Gearboxes

This master thesis is performed at Scania Axles and Gearboxes, a production plant located in Södertälje. Within the plant axles, gearboxes as well as central gears are assembled from components to finished products. All production is conducted on production lines, with a pre-determined rate, which is supplied with components by the material handling department. Since the production quantity and the mix of product variants produced on the production line is customer order-based, the number and type of components needed for production as well as appropriate staffing within the material handling department is difficult to predict. Scania is currently using a number of different resource planning tools for each material handling-department within Axles and Gearboxes to visualize the workload within the departments.

Bidragsanalys av dimensioner och postningar : en studie vid Vida Alvesta

An old and well known problem in sawmilling is to determine which dimensions /products those are most profitable to produce. Existing optimization models maximize the value of the log. In other words, based upon the market prices of the dimensions the models calculate the best way to split the log. Yet there is a great uncertainty if the most well paid dimensions really are the most profitable to produce. The costs of the process from lumber to sawn products are hard to determine and are therefore often left out from the optimization process. In this study the economic contribution of different dimensions/products are analysed.

Energieffektivisering av Åhlénshuset i Umeå : Utredning av åtgärder för ventilation, värme och kyla

Sweden is a country that has made some progress in developing energy efficient solutions. The problem in Sweden is that many houses and apartment buildings are old and have inefficient ventilation- and heating systems. This energy is lost when systems are inefficient, which then results in huge economic costs. Luckily, more and more people are becoming aware of this, which means that Sweden is on track to become even better within energy efficiency.Energy use for the housing- and service sector amounts to 166 TWh of total use at 616 TWh. Without distribution and conversion losses, these figures show that the housing- and service sector accounts for almost 40 % of the country's total energy consumption.

Goat production in Laos and the potential of using Erythrina variegata as a feedstuff

Lao People?s Democratic Republic (PDR) is a country where the majority of the population works within the sector agriculture in one way or another. The number of goats are increasing and the animals can be an important income source for families. However, during the dry season, lack of feed is a great problem for the farmers. Fodder trees have shown great potential as dry season feeding, due to that the trees often hold green and fresh leaves a long time into the season, compared to grass that dry out quickly.

Statusbedömning och förbättringsförslag för startkedjemaskineri, startkedja och linspel för stränggjutningsmaskin

The main goal with the master thesis has been to do a status evaluation of the chain machinery with its start chain and wire to secure the production on a short basis due to that a reconstruction is not planned at this time. An evaluation of the condition of the start chain and the rollers in the chain depository has been done. An offer has been requested for a new start chain and the evaluation of the start chains may be a basis for the decision taking. The production has been able to go on, although it has arisen some problems which have been difficult to find the causes for. There is no gathered ?picture? of the machinery status and a mapping of each machinery has been compiled of comprehensive logs.

Volymsrapportering vid drivningsarbete

Reporting harvested and forwarded volumes are important for the forest industry as it provides information of the size of the stock and facilitates logistics. Figures from Holmen Skog show low reporting frequency. The purpose of this study is to investigate the reason and find suggestions for improvement. A total of 17 machine operators were interviewed using a questionnaire combined with open questions. The results show that the majority of the machine operators find it simple to use the reporting system, although, some of them reports that it doesn?t always work as supposed to.

Att skapa nya rum : Roomservice - en annan form av marknadsföring

Due to the technical development the enterprises of today are forced to creative thinking when it comes to marketing of their products. An example of one of these new methods are the development of product placement which has come to an interesting turn namely advertiser funded programming (AFP). Instead of the product just being a small part of the storyline it has become the story itself. The purpose of this study is to analyse how the advertiser funded tv-production Roomservice, a Swedish home styling program, communicates with it?s viewers as well as how they perceive the message.

Systemlösningar för plus- eller passivhus : En studie med syftet att lösa energibehovet för ett specifikt hus.

The purpose of the house which is the basis of this report is to be able present itself on the market as a relatively cheap and at the same time a climate friendly choice. The house is supposed to be able to be built anywhere in Sweden and the rest of Scandinavia in a short period of time. This puts demand on what kind of heating system the house can have, since not all places have the geographic advantage of being able to use geothermal or district heating. Therefore the heating system choices will only include those that are not limited by their geographic location. The house will be built in modules which only require the groundwork to be done before the house can be erected. In this report "System solutions for plus or passive-housing" a comprehensive literature search has been conducted as well as a number of calculations.

Hållbar köttproduktion och köttkonsumtion i Dalarna

The release of green house gases and the environmental impacts humans have on the environment are huge and might cause irreversible changes to our earth. Meat is considered to have large impacts on the environment, especially beef meat and therefore there have lately been considerable discussions on the sustainable level of meat consumption and production. The main goal with this thesis is to study sustainable meat production and meat consumption in the county of Dalarna in Sweden. Indicators for sustainable meat production and meat consumption were developed and applied on three cases. Interviews were carried out with a municipality in the region that represents the consumer and three beef farmers that represents the producers.

Framtagning av beräkningsprogram för helsvetsade balk-balkinfästningar i stål : Verifiering genom fullskalig belastningsprovning

AbstractPurpose ? The purpose of this study is to investigate possible reasons for long lead-time in a customer driven production, and how the lead-time can be reduced. To fulfil the purpose the study has been broken down into two questions.1. Whichfactorsaffectthelead-timeinacustomer-drivenproduction?2.

Effektiv mjölkproduktion : en fallstudie av effektiviteten i svenska, tyska och nederländska mjölkproducerande företag, samt en kartläggning av effektivitetspåverkande faktorer

In a time when milk producing farm businesses face decline in profitability it is of great importance to examine how the situation can be improved. This thesis is a study off efficiency in milk producing farm businesses represented by Swedish, Dutch and German farms. The aim of this study is to investigate whether any differences exist between companies in these countries. Moreover, the study includes a mapping of a number of factors that determine how efficient milk production can be managed. This mapping is based on a literature review on prior efficiency studies followed by qualitative interviews with milk production advisors as well as a questionnaire sent out to dairy farmers in Sweden.

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