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119 Uppsatser om Biomass - Sida 5 av 8

HUR KAN VI REDUCERA DEN INTERNA ÖVERGÖDNINGEN SAMT REGLERA ALGBLOMNINGAR FRÅN ATT NÅ EGENTLIGAÖSTERSJÖNS KUSTZON ?? : En vision om att återfå en balans i Östersjön genom att skörda algöverskott och använda biomassan som en framtida råvara.

The Baltic Sea is one of the world?s most polluted seas. Increased discharge of nutrients due to greater populations of people, together with a slow water exchange, creates great stress on the sea. Too much nutrients leads to increased growth of algae and causes problem in the ecosystem. Even if we reduce nutrient discharge the problem still exist in the ocean. When algae dies and sinks, more nutritional substances is produced called "internal eutrophication". This phenomenon will grow in the future due to a warmer climate and the problem is spreading towards the coastal zone, which is an important site for fish recreation. By removing the abundance of algae, the nutritional and toxic substances are reduced and the algae Biomass can be a future resource for biofuel production..

Liquid diesel biofuel production in Sweden : a study of producers using forestry- or agricultural sector feedstock

The transportation sector is the only sector of the Swedish society that is still increasing the emissions of carbon dioxide and other green house gases. Diesel fuel represents one of the fuels that contributes to these emissions and the use of diesel fuels is increasing every year. The main purpose of this study was to make an estimation of the current business situation for producers of liquid diesel biofuels in Sweden such as biodiesel, synthetic diesel and crude tall diesel and examine the forces of competition of the industry today and its future prospects. The study revealed that the rivalry among the existing firms was low mainly due to the geographical spread of the companies. Moreover the success of the biodiesel industry was influenced by a long-term guarantee of the tax exempt for biofuels and by the price level of petroleum diesel.

Marknadsundersökning för SCA Skog AB avseende utbor i Mälardalen :

The need of raw material does of course fluctuate but the long term view is an increasing demand due to the growing consumption of sawn timber products, pulp, paper and lately also Biomass. This has led to a keener competition for wood. At the same time there is an ongoing structural change of a significant part in the Swedish wood supply market, the private forest owners. In 1992, 22 % of Sweden´s 335 000 private forest owner lived apart from their forest. In 2007 this figure had risen to 36 %.

Hur lokal bioenergi kan bidra till att Uppsala kommun når klimatmålet 2050

The purpose of this thesis was to examine how locally produced bioenergy may contribute to meet the climate target year 2050 in the municipality of Uppsala. The goal of reduced GHG-emissions from current 6,8 ton CO2-equivalents to 0,5 ton CO2-equivalents per capita and year, year 2050 is based on avoiding harmful penalties of an increased level of GHG in the atmosphere. By estimating available Biomass in the county together with examining future technologies and emission factors for the substrates used, four possible future scenarios has been developed focusing either on electricity generation or production of biofuels. GHG-emissions of year 2050 have been calculated using the software LEAP. The conclusion is that bioenergy, depending on how it is integrated in the energy system, may reduce greenhouse gas emissions between 0.6 ton CO2-equivalents and 1.4 ton CO2-equivalents per capita or 12% to 25% compared to 5.5 ton CO2-equivalents in the reference scenario 2050. The greatest reduction is obtained if biofuels are produced in combination with energy efficient heat requirements in buildings..

Gremmeniella abietina-epidemin 2001 : har skogen återhämtat sig?

The fungus Gremmeniella abietina causes damage to conifers that can lead to tree death. In 1999 and 2001 the pathogen caused severe attacks in Sweden, where about 500 000 ha of pine forest were affected. Trees of all ages were attacked, but mainly forests between 30-60 years that were ready for their first commercial thinning. After recommendations from the forest agency, sanitary fellings were made to trees that had more needle loss than 85%, a total of about 50 000 ha. Economic losses have been estimated to more than one billion SEK.

Biomassa fo?r rening av metallkontaminerat grundvatten : En underso?kning av biomassamaterial i Uganda

Va?rlden sta?r info?r ett stort vattenfo?rso?rjningsproblem som ma?ste lo?sas ? sa? ma?nga som 884 miljoner ma?nniskor anva?nder idag potentiellt fo?rorenade vattenka?llor till sitt dricksvatten. Denna rapport fokuserar pa? ett av de drabbade la?nderna som a?r Uganda. Syftet med projektet a?r att underso?ka vilket/vilka av de fem olika ugandiska va?xterna; Erythrina abyssinica, Musa spp, Cyperus papyrus, Imperata cylindrica och Coffea canephora som a?r mest la?mplig fo?r rening av kadmium- och blykontaminerat grundvatten.

Utvärdering av skördetidsprognoser i vall :

Sammanfattning Ensilerat vallfoder är ett av de absolut viktigaste fodermedlen för att förmå korna att producera en stor mängd högkvalitativ mjölk. En hake är dock att ensilaget ska vara av god kvalitet och med bästa möjliga näringsvärde, samtidigt som man även vill ha volymmängder. För att få detta gäller det att skörda vid rätt tidpunkt, vilket kan vara svårt att veta när det infaller. Till detta finns ett hjälpmedel som kallas skördetidsprognos. Detta går ut på att man klipper prover i vallen upp till tre gånger innan första skörden för att analysera gräset och därigenom kunna avgöra när bästa tiden är för att skörda för att få den mest optimala kombinationen av mängd och näringsvärde. Syftet med detta arbete är att undersöka hur bra hjälpmedel jordbrukare i norra Sverige tycker att skördetidsprognosen är för att få en ökad kvalitet på ensilaget, samt att jämföra variationen i näringsvärde och mängd Biomassa inom och mellan olika fält.

Effekten av klimatförändringar påkontrollbehovet av åkerogräs

With a changing climate, we can expect higher temperatures and more precipitation in Sweden.As the temperature increases, new weed species are expected to migrate in from more southerlylatitudes, resulting in requests for new techniques for weed control. In addition, we might see agreater number of weed species and higher Biomass production due to increased concentrationof CO2 in the atmosphere.Increased understanding of the biology of specific weed species will become more importantin future weed control. This will help to control the weeds more efficiently. Higher prices onpesticides and a public demand for reduced use of pesticides make growers more inclined to usemechanical weed control on a larger scale and to a greater extent prevent weed establishmentbefore sowing. A well-planned crop rotation is the most important preventive measure, whichmight also include delayed sowing, and dark harrowing and sowing.Research takes place on many levels within the weed area and several alternative methodsare being developed.

Kloridhalter i gran utmed en depositionsgradient för havssalter :

The knowledge of the chloride content and its fluxes and patterns in trees is insufficient. Increased knowledge would be desirable, one of many reasons is to be able to more efficiently meet the problems that the substance causes in the pulp industry. The purpose of this study was to examine and describe the chloride concentration of Norwegian spruce (Picea abies L. Karst.) in the south of Sweden. Furthermore the aim was to be able to predict chloride concentration from readily measurable site factors.

Implementation of renewable energy in the Republic of Moldova : society and landscape in transition

The Republic of Moldova, situated in eastern Europe and a former part of the Soviet Union, is now experiencing a phase of transition in both society and landscape. They have hardly any fossil depots and are currently dependent on Russian gas, with 97% of their energy needs imported. The new elected government wants to move towards the EU and this is generally seen as the way to grow and reduce poverty. Security in the energy sector is important and one tool is to increase the use of renewable energy sources. Through interviews, texts, and visits I have studied the implementation of renewable energies (RE) in Moldova through a society development perspective. The study has aimed to investigate the sociotechnical complexity of this subject and to discuss the potentials and way of dealing with the subject in the specific cultural context of Moldova.

Integrering av pelletsfabrik med Rya kraftvärmeverk i Göteborg : en teknisk och ekonomisk utredning

Göteborg Energi has a surplus of district heating during spring, summer and fall. The heat surplus is due to a constant production of waste heat from oil refineries and heat from waste incineration over the year. It would be desirable to increase the demand for heat and the uptime for the newly built combined heat and power generation plant, Rya Kraftvärmeverk. One alternative could be to integrate Rya Kraftvärmeverk with a pellet production facility. By producing heat, electricity and pellet in a joint process the energy use can be decreased.

Från alger till biodiesel - Den italienska drömmen?

This project aims to investigate whether algae can be used for biodiesel production in Italy. Algaes are a good option since they are fast growing and do not occupy arable land. The aspects that have been considered are growing, harvesting, which algae strain that is most suitable, extraction of oil, the production of biodiesel and where in Italy this could be possible due to climate. Cost? and energy calculations have been made to investigate if biodiesel produced from algae would be profitable. During the production of biodiesel there are several residues obtained. When the oil has been extracted from the algae, biogas is produced from the residual Biomass by anaerobic digestion and then the electricity that can be produced is supplied to the production of biodiesel.

Marktäckande, lågväxt vegetation på ställverksmark : en biologisk bekämpningsmetod mot ogräs

Unwanted vegetation on the land of electric transforming stations is a problem, in the sense that it contributes to higher fire risks and also constitutes an obstacle for people performing maintenance operations at the station. Such unwanted vegetation is controlled using herbicides and mechanical measures. Since the use of herbicides implies environmental hazards, there is a need to find alternative ways of fighting the unwanted vegetation. Investigation into suitable plants for ground cover, trials in the greenhouse, trials in the field, soil analyses and compilation of experiences from similar trials are parts of this work. The paper also contains analyses of possible environmental benefits and economical gains. There is also a final discussion of some proposals regarding alternative weed controlling methods.

En jämförelse mellan får- och nötkreatursbetade hagmarker med avseende på populationsstorlek samt artsammansättning hos dagfjärilar och örter

Many of Europe?s day-living butterflies have shown decreasing populations during the last decades and many species are threatened. Many butterflies are dependent on managed semi-natural grasslands because of their richness in nectar sources and host plants for the butterfly larva. Swedish pastures are mostly managed through grazing. The number of cattle in Sweden have been decreasing while the number of sheep in the country increased by 30%.

Pelletering av tallspån : grundläggande studier

Wood pellets are an upgraded product of residuals from several wood processing industries, for example saw mills and pulp industries. The pellets are produced by pressing the milled and dried sawdust to cylindrical units with a higher density than the initial raw material. Pellets have great benefits compared to the raw material: high energy per volume, good transport and storage properties and homogeneity. Several parameters collaborate in the whole process, which makes it complex. Wood is a heterogeneous material, chemically and structurally dependent on wood parts, habitat and storage procedures.

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