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176 Uppsatser om Unheated greenhouse - Sida 10 av 12

Biogasproduktion genom tvåstegsrötning av drankvatten

During the 19-century a global warming has been observed, which includes increases in global air and ocean temperatures, widespread melting of ice and snow, and rising global sea level. There is a clear connection between emissions of greenhouse gases caused by the human and the increase in temperature. Climatic changes caused by global warming can be stopped trough decreased emission of fossil fuels, for example by an increased use of biogas. Biogas is a renewable energy source which is produced through anaerobic (oxygen free) digestion of organic material. The gas is a mixture of methane (CH4) and carbon dioxide (CO2) and can be among others used as fuel in vehicles.

Driva tulpaner i näringslösning eller i jord :

The aim with this thesis is to make a comparison between forcing tulips in a hydroponic system and the forcing off tulips that have been planted in soil. The results are mostly based on interviews with six Dutch and one Swedish tulip forcer and the managing director at the Horticultural Research Centre, Proeftuin Zwaagdijke, in the Netherlands. There are benefits and disadvantages with both methods. Tulip bulbs planted in soil seem to get a brighter colour after forcing, compared with those forced ?in water?.

Hållfasthetsegenskaper i gjutjärn : tensile properties of cast iron

In the last few years people have become more and more aware of how humanity is affecting the climate. In the direction of reducing the greenhouse gases is to design engines with higher tensile properties and reduced weight, in order to achieve lower fuel consumption and cleaner fuel incineration in today's truck engines.In order to achieve these requirements it?s necessary to increase the combustion pressure in the engine. This requires higher tensile properties and high thermal conductivity of the engine material. The department of Component Technology at the University of Jönköping in collaboration with Volvo Powertrain AB, Scania CV AB and DAROS Piston Rings AB has been commissioned to develop this material and to find knowledge of material properties used in truck engines and piston rings used for marine applications.The purpose with this work is to analyze the tensile properties of a series of cast iron, cast under different metallurgical conditions.Four different series of cast irons have been analyzed from four points of view, carbon concentration, nodularity, amount inoculation and cooling rate.After the tensile test all specimen data was analyzed in a mathematic calculation program called Matlab 2006a.

Ärtrev som substrat för biogasproduktion : En litteraturstudie och rötning i labbskala

Until 2020, 49% of Sweden's use of energy must derive from renewable sources. Greenhouse gases must as well decline with 40% compared to 1990 as a part of Sweden's 16 environmental objectives. Biogas is part of the effort to achieve these objectives, but as the demand for biogas increases, more substrates are needed to meet the demand. The purpose is to investigate the conditions for pea residue as substrate by performing lab-scale mesophilic digestion with different fractions and notch lengths and then to summarize pea residue as a substrate for biogas production. During anaerobic digestion, 1000 ml bottles were used as reactors for digestion.

Ökad användning av biodrivmedel i vägtransportsektorn : en styrmedelsanalys

The Swedish road transport sector relies almost completely on fossil fuels. In 2007, as much as 96 percent of the total sales of fuels was made up of petrol and diesel, while at the same time the share of total emissions of greenhouse gases in Sweden that came from road transports amounted to close to 30 per cent. Sweden is by no means worse off than any other European country in these respects. In order to address the questions of high oil dependence and CO2 emissions the European Commission has proposed a reinforcement of the legislative framework, with a 10 percent minimum for the market share of biofuels in 2020. Furthermore, the proposed target is binding for the member states, unlike the current voluntary target of 5.75 percent by 2010. More than doubling the usage of biofuels in only a bit more than a decade will most likely not be possible without policy interventions.

Trädgårdsergonomi : om konsten att undvika de vanligaste riskfaktorerna för hälsan i små trädgårdsföretag med krukodling

This paper is based on a literature review and interviews made with managers in small-scale nurseries for pot plant production. The review helped to identify the worst occupational hazards in pot plant production. The interviews provided a way to investigate how the nurseries act so as to avoid the worst hazards and what they do to even out work intensive periods during the season in order to get a more even distribution of work over the year. According to available statistics problems with back and shoulders are the most common of the physical disorders and the risk for occupational accidents are high for greenhouse workers. Most of the occupational injuries are connected to musculoskeletal problems. The handling of material is often manual and involves frequent lifting and carrying of heavy loads, the strenuous work postures and static muscular tensions these repetitive tasks are associated with causes straining and overloading.

Energieffektivisering och analysering av inomhusklimat genom simulering : IVT Värmepumpar, Tranås

Syftet med detta examensarbete har främst varit att förbättra inomhusklimatet i byggnaden Greenhouse, tillhörande företaget IVT Värmepumpar i Tranås. De anställda upplever problem med värme i byggnadens utbildningslokaler främst under sommarhalvåret. Tid har även lagts på att ta fram åtgärder som sänker byggnadens energianvändning i form av el och värme.Då examensarbetet utfördes under hösten användes ett simuleringsprogram för att få en bild av inomhusklimatet under sommarhalvåret. En modell av byggnaden byggdes upp i simulationsprogrammet, komplett med ventilations- och värmesystem.För att validera modellen som konstruerats utfördes flertalet mätningar under en veckas tid. Simuleringsmodellen kalibrerades sedan mot dessa mätningar för att efterlikna de verkliga förhållandena i så stor mån som möjligt.

Urban agriculture : experiences from the Swedish horticulture

Urbanisation has increased the distance between the urban and the rural. Urban agriculture can be a solution to overcome that distance. The characteristic of urban agriculture is the intensive production in intra urban and peri-urban areas. Until 1950s food production in cities was an important part of the urban economy and the urban food supply. Since the 1950s the urban located production of food has almost ceased in Sweden, partly as a result of cheap food imports.

Styrdokument för kontorsbyggnation ur ett ekologiskt hållbarhetsperspektiv : Aspekter och argument

The construction and real estate industry represents a significant part of Sweden's total impact on the environment and mainly affects the following national environmental objectives: reduced climate impact, a good built environment and a non-toxic environment. By establishing internal rules, companies within the industry can reduce their environmental impact. SMT (AB Sandvik Materials Technology), a part of the industrial group Sandvik AB, has set a target that during 2014 develop a guiding document with special consider to the environmental impact during construction of office buildings, that they establish at the Swedish regional capital Sandviken, for both internal and external tenants. This study therefore aims to clarify which environmental aspects that the construction and real estate sector mainly are responsible for, and therefore should be part of a guiding document for a company for establishing office buildings, and to present arguments regarding the use of such a document. The study is based on literature studies and personal contact with other companies, in the form of e-mail conversations and a telephone interview.

Towards sustainable rye cultivation : soil carbon and yield modelling for crop rotations with rye

Using the Introductory Carbon Balance Model, ICBM, five different crop rotations with rye 1. Rye-Ley-Ley-Rye-Beans-Rye 2. Rye-Rye-Rapeseed-Rapeseed 3. Rye-Ley-Ley-Rye-Potatoes-Rye 4. Rye-Rye-Potatoes-Wheat 5. Rye-Rye-Potatoes-Beans-Wheat-Rye-Potatoes-Rapeseed were tested theoretically in four different cultivation scenarios ? Straw left on the field, biogas digestate added as fertilizer. Labelled ?+straw+BD?. ? Straw left on the field, only synthetic fertilizer. Labelled ?+straw-BD?. ? Straw harvested, biogas digestate added as fertilizer.

Utsläpp av växthusgaser och ammoniak från hemkomposter

Hemkompostering är fördelaktigt bland annat därför att det kan leda till minskade transporter av sopor och därmed koldioxidutsläpp, samt att den färdiga komposten kan användas som näringstillskott för växter. Kompostering av matavfall innebär dock en risk för bildning av metan och lustgas, vilka är starka växthusgaser. Även ammoniak, med försurande och övergödande effekter, kan släppas ut från komposten under vissa förhållanden. Det här arbetet syftar till att undersöka utsläppen av dessa ämnen, samt öka kunskapen om hur skötseln av komposten påverkar utsläppen. Vid tre tillfällen under juni och juli 2010 utfördes mätningar på 20 komposter i Uppsala.  Temperaturen mättes i komposten, prov togs av gasen i kompostoch prover av materialet togs även för analys av vattenhalt, pH och askhalt. Hushållen förde också protokoll över sin skötsel av komposten under tiden för mätningarna.

Concentration and offtake of trace elements and macronutrients in Italian ryegrass (Lolium multiflorum Lam.) and spring barley (Hordeum vulgare L.) grown on soils amended with water treatment residual sludge

Aluminium sulphate (Al2(SO4)3) is usually added during the drinking water treatment processin order to precipitate organic and inorganic material, resulting in aluminium-based drinkingwater treatment residual sludge (WTR). Since 2003 Swedish law no longer permits WTR tobe deposited in lakes, and there is an interest to explore the possibility to utilize WTR as soilamendment. The aim of this study was to examine the effects of WTR application on cropgrowth and concentrations of macronutrients and trace elements (including micronutrients andpotential toxic elements). A greenhouse pot experiment was conducted with three soils; a clayloam rich in phosphorous (P), a loamy sand rich in P, and a silty loam with a low soil Pconcentration, and two crop species Italian ryegrass (Lolium multiflorum Lam. cv.

Koldioxidlagring - realitet eller utopi? : En komparativ fallstudie med syfte att undersöka potentialen för koldioxidlagring i geologiska formationer och biologiska sänkor och dess förmåga att bidra till hållbar utveckling

To curb greenhouse gases and mitigate climate change is one of the biggest challenges human society face today. Carbon dioxide (CO2) has accumulated rapidly in the atmosphere as a consequence of burning of fossil fuels and deforestation. The aim of this study is to explore two methods to store carbon dioxide in geological formations and biological sinks. The aim is also to discuss the two mitigation options from a sustainable perspective and whether it can lead to a better environment and benefits for local and global societies. The research questions are: Which method to store carbon dioxide, geological or biological, is the most effective? Which method to store carbon dioxide, geological or biological, has the greatest potential to promote sustainable development for local communities?The method used is a comparative case study and presents four case studies that explore the potential for CO2 storage offshore in Norway and Brazil; and in tropical forests in Mexico and Brazil.

Methane production from dairy cows : relations between enteric production and production from faeces and urine

Methane (CH4) is a greenhouse gas (GHG) that contributes to the global warming. One of the largest sources of methane is livestock, preferably ruminants which alone counted for 30% of the total agricultural anthropogenic methane emissions in the year of 2000. The reason to why ruminants are such large contributors of methane are that the gas is produced in the rumen by enteric formation and leaves the animals by belching, exhaling or by the excreta.Diets high in concentrates can result in a lower emission of methane. Also diets with a high content of starch, such as alfalfa-grass, have a methane-decreasing. It is profitable to reduce enteric methane formation since that form of methane is unavoidably lost.

Beräkning av koldioxidutsläppet från bostadssektorn i Stockholms län

During the last decades the housing sector has increased continuously, and housings and services accounted for 40 % of the energy usage in Sweden during 2011. The expansion in number of buildings in society has resulted in an increase in both energy usage and emissions of greenhouse gases. It is crucial to enable a sustainable development of society and as a result, the demand to reduce the emissions of carbon dioxide is a current question. In this study, the carbon dioxide emitted from the housing sector in Stockholm is estimated. The housing sector can be divided into different types of houses such as apartment blocks, single-family houses and holiday houses. By collecting information of the energy purchased in respective households, a computational model is generated that calculates the total emission of carbon dioxide.

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