Sök:

Sökresultat:

739 Uppsatser om Organic rankine cycle - Sida 10 av 50

Rötning av matavfall ? en studie av metanutbytet hos matavfall förbehandlat med skruvkrossteknik samt vid samrötning med bioslam från pappersbruk

Today's society is facing major challenges. In order to reduce the climate impact fossil fuels should be replaced with fuels that do not contribute to the greenhouse effect. The growing population generates organic waste originating from industry and households so called organic fraction of municipal solid waste (OFMSW). Through anaerobic digestion, waste can be utilized to produce energy-rich methane gas. In this way, waste can be a resource instead of a burden on society.

Utveckling av substratmixen vid Mosseruds biogasanläggning : Substratkartläggning och rötningsförsök i laboratorieskala

The world?s growing need for energy together with a desire to ward off the worst consequences of global climate change has resulted in a never seen desire to invest resources in renewable energy sources. Biogas production through anaerobic digestion is one of those growing energy sources. In Sweden there are over two hundred plants that uses this biological process to break down organic substances while producing carbon dioxide and the energy-rich gas methane.This master?s thesis has focused on development of the mixture of different organic substances that is treated at a specific plant, namely Mosserud biogas plant.

Livscykelanalys av flerbostadshus ? energieffektiviseringsåtgärder för minskade koldioxidutsläpp

The importance of energy- and environmental issues has increased, and the work towards reducing carbon dioxide emissions plays a major part. The European Union has set up goals for the membership countries to work towards this to happen. The carbon dioxide emissions in Sweden have been reduced the last few years, but there is still a lot to do. About 30 per cent of Sweden?s carbon dioxide emissions generate from energy usage related to housing, this is why the housing sector is of interest to examine.

Optimering av biologisk fosfor och kvävereduktion i ett reningsverk för hushållsspillvatten

In connection with Henriksdals wastewater treatment plant (WWTP) a smaller plant is situated called Sjöstadsverket where new methods for wastewater treatment are tested and evaluated in different process lines. On one of the lines experiments with enhanced biological phosphorous removal (EBPR), have been carried out to evaluate if it is a good alternative to traditional chemical phosphorus removal. This thesis evaluates the results from the experiments conducted during fall 2005.The incoming water from Hammarby Sjöstad consists of only household wastewater, which gives a wastewater with high concentrations of nutrients and organic carbon. This is partly positive, because one of the limiting factors for effective biological phosphorus removal is the lack of easily biodegradable organic carbon. The high concentrations of ammonium and phosphorus demand a high reduction to achieve the requirements of outgoing concentration.To optimize the process experiments with different recirculations and different aeration techniques have been made.

Relevanta, unika och alldeles lagom gröna

The business world has been through an extreme transformation over the past decades, which have forced companies to look at themselves from a new point of view. Consumers have a complete new set of ways to gather information and are more motivated than ever to make sustainable consumption choices. This change of attitudes among consumers has made companies focus on other things than price versus quality. A whole new concept has been brought up to questioning: environmentalism. Consumers demand more organically produced products.

Bok- och grankonkurrens i Sydsverige - markegenskaper och naturlig föryngring :

In southern Sweden, beech (Fagus silvatica) and spruce (Picea abies) are two species with similar demands on soil properties. With increased global warming and high acid deposition the future may bring larger areas were the two species are overlapping, competing for the same soil. The aim of this study was to compare spruce and beech concerning distribution, cultivation and soil properties. From available data comparisons were made between spruce and beech forests in Sweden. Soil analyses were made on samples from beech forest in southern Sweden, with and without natural regeneration of spruce.

Effekten på nedbrytningen av rötter vid tillförsel av ammonium sulfat i en granskog i sydvästra Sverige

Decomposition of organic matter is a critical process in the ecosystem, which involves many essential biotic and physical parts. Decomposition is therefore an important process both above and below ground. The rate of decomposition is dependent of many environmental factors for example: pH, moisture and supply of oxygen. The decomposition can therefore be affected by large scaled environmental influences, such as acidification and climatic changes. The root litter in the forest is in different ways affected by acidification, liming and manuering.

Decentraliserat lager - ett steg mot flexibilitet

This study was conducted at Glimek AB, a company that has chosen to decentralize its central storage unit in order to increase production efficiencies. The purpose of the study was to identify the problems in the production cycle that lead to the decision to decentralize the central storage unit, as well as identifying what the decentralization entails. The effects of the decentralization have not been analyzed in the study, and consequently neither financial nor production disadvantages have been considered.Appropriate questions were formulated based on the chosen underlying theories, and were asked to selected individuals with relevant knowledge. The study is based on the information that was gathered from interviews with management as well as staff within the company. In addition, supporting information such as flowcharts, drawings, orders and decision support documents were supplied by the company.

Vallört som växtnäringskälla : växtnäringsförsök och litteraturstudie

Russian comfrey, Symphytum x uplandicum, was tested as a plant nutrient source in a trial with tomatoes. Comfrey liquid was produced by Stiftelsen Holma i Höör. Tomato plants of the cultivar Aromata planted in a medium of soil:peat (1:1) enriched with organic nutrients and lime, were fed with comfrey liquid plus Biofer, in three different concentrations. Two different concentrations of BioRika were used as comparison, along with an unfertilized control group. In the comfrey treatment I a total amont of 1g N, 0,23 g P, 0,84 g K, was given to the tomatoes.

Utvärdering av 3dvia Composer : -För arbetsinstruktioner och beredning

With recent technical development computer aided design and manufacturing has taken amore important role in the product life cycle. New business segments such as Product/ServiceSystems and remanufacturing is emerging. This development demands better control of theproduct data throughout the entire product life cycle. Computer aided design is widelyrecognized and used within the manufacturing industries and in recent years the importance ofDigital manufacturing has increased. One part of Digital manufacturing is paperlessproduction which involves all orders and working instruction shown for example on a screenrather than on a piece of paper.

Vilken effekt har lärkrutor på ogräsfloran vid ekologisk höstveteodling? :

This study forms part of the R&D project "Improved survival of bird chicks in organic fields" managed by the Rural Economy & Agricultural society in Uppsala. The skylark (Alauda arvensis) is a species that has decreased drastically in Sweden as a consequence of more intensive cropping. Studies in England have shown that skylark reproduction can be greatly improved within conventional fields, at a low cost, by establishing patches of bare ground (skylark plots). Within conventional farming, herbicides can be used in case a weed problem arises due to implementation of these skylark plots, whereas this is not allowed in organic farming. This study examined the effects of skylark plots on the weed culture in organic autumn-sown (winter) cereals and whether weeds might cause long-term problems to farmers. The study was conducted in two parts; a field study and a review of the literature regarding the weeds observed. The field study was carried out in 2007 during three weeks in June and three weeks in July, on eleven organic fields with winter cereal in the vicinity of Uppsala.

Reproductive physiology of the female cat

The cat is one of our most common pets. Understanding the reproductive physiology of the queen is important, not only for the knowledge of our domestic cats but also for wild undomesticated feline species, many of which have been reported endangered. Understanding the mechanisms behind the estrous cycle, ovulation and pregnancy is also important for handling the feral cat populations that are a problem in several countries. The purpose of this literature study is to look into the hormonal patterns of the reproductive physiology of the female cat, with focus on ovulation, pregnancy and pseudo-pregnancy, and from this information determine in which fields more research would be needed. The female cat is seasonally polyestrous in Sweden, meaning that she can have several estrous cycles during the breeding season but goes through a long period of reproductive dormancy during the darker months of the year. The queen is considered an induced ovulator, with copulation triggering the release of luteinizing hormone (LH) from the pituitary gland needed for ovulation.

Identifikation av produktionsstörningar och obalanser vid tillverkning av golvskenor

Our report procedure identification of instability and disturbance in an automatic manufacturing line of processing and assembling of chair sliding rails at Sapas manufacturing department in Vetlanda.To obtain a stabile ground we have mapped the material flow to receive a comprehensive view and to visualise connections.We have examined cycle times at different stations in purpose to identificate bottlenecks. The result of our examination showed that the bottleneck of the line was the brush station. This leads to that the expected bottlenecks identificated by Sapa gets a delay time and by that a longer cycle time.Interruptions has a clear negative influence at the line performance so we have also assemble data through the operators report list and compiled these in order to find out the interruptions effect on the line. The outcome during our assembled period was that the reported interruptions corresponded about 30 percent of the total available production time. This has a clear negative effect on the line productivity and efficiency as we have calculated in order to get the present status..

Finansiella garantier - en möjlighet att säkerställa ett miljömässigt omhändertagande av uttjänta produkter

Extended Producer Responsibility (ERP) is a form of product take-back regulation that requires the producers to manage their products at the end of life. By internalising the products? entire life cycle costs into the market price the ultimate objective of such regulations is to reduce the environmental burden from the products. This Master´s thesis seeks to examine if the total life cycle cost of a product actually is borne by the producer, and if not, predict who will then take this cost. This is done by analysing the market for take-back activities in three different categories of products; electrical and electronic equipment, cars and wind power stations.

 En jämförelsestudie av koldioxidsläpp för en byggnad med trä- respektive betongstomme ur ett livscykelperspektiv

The goal with this examination thesis is to investigate the difference in carbon dioxide emissions between a building with a wooden versus concrete carcassing from a life cycle perspective. The huge amounts of carbon dioxide released into air from human activities must be reduced to prevent serious consequences. A way to limit this issue is through performing a comparative study where the result shows which of two products with the same function has the lowest emission of carbon dioxide, whereof the product with the lowest carbon dioxide pollution can be chosen.To be able to perform a study like this an object has been chosen and studies about life cycle analyses have been done. The rental square meter, the thermal conductivity value, the energy requirements and the placement of the building has been set equal in both framework types. There were solely dissimilarities of the two buildings taken into account when this comparison study was performed.The result of the study is that a building constructed with a wooden carcassing has the lowest amount of carbon dioxide emissions.

<- Föregående sida 10 Nästa sida ->