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882 Uppsatser om Pre heating of wood chips - Sida 14 av 59

Productivity of integrated harvesting of pulpwood and energy wood in first commercial thinnings

The aim of this study was to quantify the productivity and the costs of different harvesting systems (teams), containing harvesters equipped with accumulating harvester heads and forwarders, in first commercial thinnings were an integrated harvest of pulpwood and energy wood were performed. In the beginning the plan was to study and measure 20 sites before and after harvest. Due to storms during the summer of 2010, complete data could only be obtained from 8 of these 20 sites. Seven of these sites were privately owned and one was owned by UPM, all of the sites had been pre-commercially thinned. The mean stem density before harvest was 2578 stems per ha and the mean stem volume was 0.074 m3solid over bark.On average 1518 stems/ha was harvested.

En byggnads energibehov : En studie om energieffektivisering av en befintlig byggnad i södra Sverige

The purpose of the study was to investigate the use and losses of energy in an existing older building. Another purpose was also to look through various options for heating systems with renewable energy in the building. The aim was to reduce the use and losses of energy. The first step was to study the related electricity bills of the building and also perform measurements and calculations of the building envelope and ventilation. The next step was to find out the possible actions for energy saving by performing measurements and calculations.

Beslut om investering i alternativ energi : en studie om hur lantbrukare fattar beslut vid investering i halmpanna

Interest in alternative energies is high in Sweden today, particularly in the agricultural sector. According to the Swedish lantbruksbarometern (2009), almost all respondents consider the use of some form of alternative energy from the farm. While interest in alternative energies is large, attention to the alternative energy straw has fallen and is almost nowhere mentioned in the literature today. Three years ago, in the Lantbruksbarometern nearly 44% of the farmers would be willing to invest in straw as heating system on the farm. How do the farmers decide to invest in alternative energies? With this information a problem is presented for this paper.

Energianvändning i serverhallar: energiflöden och kylning

This thesis examines different methods for the cooling of data centers. Several means of cooling with the refrigeration cycle have been studied, as well as the feasibility of using free cooling in different parts of Sweden. In addition, the possibilities of transferring excess heat to a nearby district heating system were investigated. It was found that in all investigated cases except two, the data center could be cooled solely with free cooling for at least 300 days a year when only the outside air temperature was considered as a constraining factor. The limit was then set to 20 °C.The vast majority of all district heating systems in Sweden get little to none of their heat from other excess heat sources.

Värmesystemsutveckling

In cooperate with Asko Cylinda we have developed a new heat system too short the process time and reduce the energy consume in a dishwasher and still have it too be a class AAA. The environment and quality is important for the company too still be the number one on the market, If they want too keep that position the product developed of new innovations will be very important. The systems we have developed are more effective and reduce energy up too 25 %. The process time is reduced too less than two hours, from the today two and half-hour. The solutions are too heat up the rinse water and the dishwater at the same time, with a new heating system and it make are solutions unique and effective. Its good for the dish and the environment.

Kvalitets och förbättringsarbete för ITtjänsteföretag

Wavecraft AB develops medical equipment for heating of organic synthesises. The heating is done with microwaves, which improves the process in both speed and accuracy compared to the more traditional methods where heating elements are used. This report discusses the developement of an automatic lid mechanism for one of Wavecraft's product prototypes. The company assumes that the final product will be integrated by customers into fully automated systems, and the upgrade from a manually to an automatically controlled lid is therefore an important step in the product's developement process.The first stage och the project was an idea generation process. The ideas generated here were organized into five different concepts of which the best one was selected through the use of a concept matrix.

Primärenergianvändning av passivhus i Sverige : Med fokus på Kvarteret Trettondagen

The building sector accounted for around a fourth of the total energy usage in Sweden in year 2010 (Energimyndigheten, 2012). Therefore it has become very interesting to achieve a lower energy usage in residential buildings. One way to achieve that is to build so called passive houses. By being very well insulated and have low leakage through the walls, they can reduce the energy usage for heating with a substantial amount. The first passive house was built during the 90?s in Germany; and in Sweden the first passive house was built in Gothenburg 2001.

Val av energisystem för en hållbar stadsdel : En fallstudie av Östra Sala backe

Uppsala County has ambitious environmental aims for the planned residential area inÖstra Sala backe. In this thesis different energy sources have been evaluated todetermine which system that would be most favorable given currently availableinformation about the project. Planned energy usage has been divided into tap waterheating, space heating and power. Three base case scenarios were made with districtheating, small scale bio fuel and heat pump. Solar power and solar heating were thensimulated and the production from the two could individually be deducted from theenergy need in the base cases, constituting 9 different scenarios.

Höghastighetståg - Är det framtiden?

AbstractConsider a ?uid being heated from below. The heating leads to an upward convectiveforce that is counteracted by the viscous forces of the ?uid. If the convectiveforce is large enough in comparison to the viscous forces the ?uid will be put in anunstable state.

Energieffektivisering av flerbostadshus i miljonprogrammet

This thesis has been written with our society?s current energy-situation in mind.Although it only deals with one particular block of buildings, the solutions and suggestions presented herein are quite applicable on other objects of the same type.This thesis is intended to be used as a guideline for energy-preserving projects in general, with an eye to buildings erected during the Swedish ?million-programme? in the sixties and seventies.The paper starts with the acquiring of all necessary blueprints and technical specifications. It then moves on to a thorough description of the buildings in question, and their heating- and ventilation-systems.Followed by this the reader is guided through the successive stages of energy-perseverance measures that are available, and possible. Reasoning around the economic factors concerning all measures is also held.The paper ends with conclusion, and a discussion concerning the delicate issue of the higher return-temperatures possibly reaching the district-heating plant..

Morgondagens effektiva fjärrvärme : En beskrivande litteraturstudie

This report is made as a literature review, focusing on the work done to increase understanding of efficiency in the categories of substations and secondary heating systems, with respect to the deviation from the theoretically possible cooling off in the distribution network as well as the economic benefit that appear. The main purpose of a considerable part of the literature used in this report addresses the issue of identifying individual causes of reduced cooling in district heating systems. These literature resources have been compiled and summarized as part of the report.The technology of district heating is associated with benefits such as better use of the energy in a fuel. This is the case of cogeneration plants where serial generation of electricity and thermal energy increases efficiency compared with the parallel generation where heat is generated locally and electricity is generated centrally. Serial generation thus allows for lower primary energy demand.

Rayleigh-Bénard konvektion.

AbstractConsider a ?uid being heated from below. The heating leads to an upward convectiveforce that is counteracted by the viscous forces of the ?uid. If the convectiveforce is large enough in comparison to the viscous forces the ?uid will be put in anunstable state.

Lågtempererad fjärrvärme i Umeå

People in today?s society are becoming more and more aware of how important it is to use energy as efficiently as possible. This is clearly noticeable by an increase in home produced heat with e.g. solar panels or heat pumps heating systems. These changing customer demands forces district heating technology to be redesigned, which is why there is an ongoing research regarding the next generation of district heating - low temperature district heating (LTDH).

Ekonomiska konsekvenser av förändrad röttolerans vid Bravikens Pappersbruk :

The competition for Norway spruce pulp wood in Central Sweden increases, forcing the supply-structure of Holmen to face two important challenges. Firstly, it is of the outmost strategically importance to secure the long-term supply of Norway spruce pulp wood to the industries. Secondly, Holmen desires to increase the obtainable volume of Norway spruce pulp wood. This would enable the company to choose volumes in the lower price-segments and thereby decrease the dependency of costly marginal volumes. As this work shows, one part in managing these challenges could be to lower the quality standards concerning root rot (Heterobasidium annosum). Facts presented in the work shows that: 1. Technically, the TMP-industry of Braviken can handle a much more rotted pulp wood than that used today, although the cost of refinement increases.

Effekt av biotopvård på öringpopulationen i två vattendrag

I have done a follow up study of the restoration of two rivers, Röälven and Grundan, in order to evaluate the effects of the restoration on the endemic population of trout. Both rivers have been used for timber floating during many years throughout the 20th century, and because of this, had all obstacles such as rocks and wood parts removed. In 2004-2005 both rivers were restored, and rocks and wood were put back into the rivers. Spawning grounds were created and boulder dams were constructed to promote the streaming water. The result showed that the trout population of both rivers increased after the restoration, but also that the trout population of Röälven increased more than that of Grundan.

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