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20 Uppsatser om Limestone - Sida 2 av 2

Samverkan mellan nya cementtyper och tillsatsmedel för betongtillverkning

Cement manufacture accounts for 3-5 percent of total global carbon emissions. There is a growing interest in reducing the environmental impact and conserve limited natural resources. In cement production, clinker productions consume 87.5 percent of the total energy consumed in the cement manufacture.Cementa has since many years, focused on reducing the environmental impact of cement production. The work has involved the entire production process from selection of alternative fuels to the development of cement with less clinker content. During 2013/2014, two new types of cement (Bascement and CEM II / B) will be introduced to the Swedish market.

Hydraulisk och termisk grundvattenmodellering av ett geoenergilager i Stockholmsåsen

Geothermal energy can be extracted from an aquifer, where the groundwater is used as heatexchange medium while heat and cold are stored in the surrounding material in the aquiferand to some extent in the groundwater. Application of aquifer storage for the use ofgeothermal energy is mainly used in large scale facilities and is limited to sites with suitableaquifers in the form of ridges, sandstone and Limestone aquifers.Löwenströmska hospital in the municipality of Upplands Väsby, north of Stockholm, islocated nearby the northern part of the Stockholm esker. This means that it can be profitableand environmentally beneficial for the hospital to examine the possibilities of aquifer storagein the esker material next to its property.The purpose of this master thesis has been to investigate if geothermal energy storage with aseasonal storage of heat and cold can be applied within Löwenströmska hospital?s propertyarea using groundwater modeling. A hydraulic groundwater model was constructed inMODFLOW based on a simplified conceptual model of the groundwater system.

Minskad utbredning av apollofjäril, Parnassius apollo, i södra Stockholms län : En studie av möjliga faktorer utifrån artens habitatkrav

The Apollo butterfly, Parnassius apollo, is categorized as Near Threatened (NT) in IUCN Red List. Today in Sweden it is found only in strongly fragmentized populations. In the county of Stockholm, P. apollo exists exclusively in some islands of the archipelago and with one mainland population in Stora Vika. This study has the purpose of expanding the knowledge of the local conditions for the butterfly in the south parts of the county of Stockholm and thereby contributes to a sustainable land management that can preserve the Apollo butterfly.A comparative study was done between areas where the butterfly today have: a stable population (Stora Vika, Utö and Ålö), has disappeared (Muskö and Yxlö) or is strongly declining (north part of Ornö).

Inverkan av delmaterialensvariationer på betongensegenskaper

Vid betongframställning förekommer det spridningar i delmaterialens egenskaper som påverkar den färskaoch hårdnande betongen. Spridningarna i betongens delmaterial har studerats hos tre av Skanskas betongfabriker(Göteborg, Luleå och Norrköping), genom provuttag som analyserats hos Cementa Research.Provuttag har gjorts en gång per månad under ett års tid från fabrikerna. Delmaterialen som har analyseratsär ballast, cement, flytmedel och kalkfiller (endast hos Göteborg och Norrköping). Siktning av ballast0-8 mm har utförts med den traditionella siktningen. För kornstorlekar mindre än 0,25 mm, cement samtkalkfiller har lasersiktning använts.För att få en överskådlig bild över spridningarna hos delmaterialen har en analys utförts som illusteraravvikelserna med exakta siffror.

Växters upptag av spårämnen från rödfyr : ett odlingsförsök vid tre rödfyrshögar i Västra Götalands län

Burnt alun shale and lime is the residual product that was formed when alun shale was used as fuel to convert Limestone to quick lime. The material contains arsenic, vanadium, molybdenum, cadmium, nickel, lead, and uranium among other elements. The aim of this paper is to examine the uptake of trace elements in vegetables grown on burnt alun shale and lime to determine whether or not the surrounding environment and humans are exposed to these elements by eating plant products. A cultivation trial was carried out where onion, carrot, and lettuce were grown on three mounds of burnt alun shale and lime in the Falköping area in Sweden. The treatments were burnt alun shale and lime mixed with peat, only burnt alun shale and lime, and a reference soil. The reference plots were natural soil mixed with peat adjacent to the mounds.

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