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985 Uppsatser om Aquatic plant planting in wetlands - Sida 14 av 66
Undersökning av processparametrar för optimering av sol-gelprocessen för produktion av kärnbränsle
A clean and affordable energy source for cooking is deficient in developing countries. People rely on fuels that contribute to environmental, social and health problems.Biogas is an alternative energy source and an increased investment in small-scale biogas production can in several developing countries be found. Several projects have started to use the technology in developing countries because of the benefits with biogas. Some cases in the establishment of biogas plants have succeeded and some have not. The study is a literature review supplemented by two field studies.
Geotermi i Ungern : Undersökning av Ungerns energisituation inriktat på geotermi samt kapacitetsfaktorn för det största geotermiska värmeverket i Mellaneuropa.
Hungary?s share of renewable energy in 2010 was 7.9 %, and their renewable energy goal for 2020 is 14.65 %. Geothermal energy is one option that could help to achieve the goal, since Hungary has favorable bedrock, the temperature gradient is above average and thepermeability is high. Today Hungary is importing just over half of its primary energy supply. Because of political conflicts between nations Hungary wants to expand its own production of energy.
Artrikedom av kärlväxter i övergivna och restaurerade hagmarker : betydelsen av igenväxningsgrad och tid sedan igenväxning började
Continuously grazed grasslands have remarkably high plant species diversity. In Sweden this type of habitat has declined for the last two centuries. Changed land use has caused habitat fragmentation and loss of habitat quality. This has caused a great number of plant species to end up on the verge of extinction. To try to save this unique habitat and the species that are tied to it, lots of resources are laid on restoration of abandoned grasslands.
In this study, plant species richness of continuously grazed, abandoned and restored grasslands were related to degree of overgrowth, time since overgrowth started and rate of overgrowth.
Kvalitetssäkring av markberednings- och planteringsuppföljning hos SCA Skog AB Jämtlands skogsförvaltning :
Quality assurance means to systematically work for better understanding of the customers needs, demands and expectations. The goal for this study was to investigate how quality can be assured in the job follow up that is made by forestry contractors after soil scarification and planting. The study consisted of a description over the current follow up process at SCA forest AB Jämtlands forest administration, analysis of current follow up situation and an investigation of follow up process made by contractors in other line of business.
The first step was a statistical comparison where the own follow up made by contractors were compared with follow up made by SCA them selves over 100 stands. Two soil scarification contractors and two planting contractors carried out the silvicultural measures. The results showed that significant differences between a number of quality factors measured, for example number of approved plants or approved scarification points, average score on stand and number of totally planted plants.
Optimal design av strukturer - Utvärdering av problem och lösningsförslag inom topologioptimering
A clean and affordable energy source for cooking is deficient in developing countries. People rely on fuels that contribute to environmental, social and health problems.Biogas is an alternative energy source and an increased investment in small-scale biogas production can in several developing countries be found. Several projects have started to use the technology in developing countries because of the benefits with biogas. Some cases in the establishment of biogas plants have succeeded and some have not. The study is a literature review supplemented by two field studies.
Metodundersökning av tre metoder för kvävemätning i en arktisk äng : Jämförelse mellan mätmetoderna extraktion, inkubation och jonbytesmembran (PRS-sond)
The purpose with this report was to compare three commonly occurring methods for measuring plant available nitrogen in soils. The methods extraction, incubation and Plant root simulator (PRS) probe - an ion exchange membrane (Western Ag Innovations, Inc., Saskatoon, Canada) method were used and comparison between these methods were conducted. A full factorial experiment were set up in northern Finland with the treatments excluding herbivores, warming and fertilization to see how the inorganic nitrogen content in the soil was effected by the treatments. Soil cores were taken and from them a subsample was incubated for 18 days and thereafter analyzed for inorganic N in laboratory. PRS- probes were in the ground for 1 month.
Modellering av Panna 5 Mälarenergi AB : utveckling av en beräkningsmodell med simuleringsverktyget IPSEpro
Heat and power stations are often in need of optimizations. A simulation model is a tool for findingways to optimize the plant. The scope of this diploma work is to develop a simulation model ofBoiler 5 at Mälarenergi AB. Boiler 5 is a circulated fluidized bed boiler that was taken into service inyear 2001. Among the included parts in the boiler are cyclone, convection part andINTREX-chambers.
Etablering av småskaliga biogasansläggningar i utvecklingsländer - kriterier för framgång
A clean and affordable energy source for cooking is deficient in developing countries. People rely on fuels that contribute to environmental, social and health problems.Biogas is an alternative energy source and an increased investment in small-scale biogas production can in several developing countries be found. Several projects have started to use the technology in developing countries because of the benefits with biogas. Some cases in the establishment of biogas plants have succeeded and some have not. The study is a literature review supplemented by two field studies.
Återvinning av näringsämnen från hushållsspillvatten med omvänd osmos
Hammarby Sjöstad is a new district in Stockholm with high environmental standard. Stockholm Water Company evaluates a local wastewater treatment plant with cutting edge technology. The first step is an experimental treatment plant (Sjöstadsverket) with four parallel lines of treatment, each with a capacity to treat wastewater from 150 persons. Within the membrane technology subproject the possibility of using reverse osmosis (usually called RO) to regain nutrients is examined.Reverse osmosis separates the incoming water in a clean permeate and a concentrate that, as the name indicates, is a more concentrated version of the incoming water. Using this method in wastewater treatment, a solution high in nutrients can be obtained without the use of chemical precipitation agent and with no production of sludge.
Konstgjorda våtmarksöar : flytande reningsverk?
År 2000 godkände Sverige EUs vattendirektiv. Det innebär att vi måste arbeta för att vattnet ska ha en god kvalité och det får inte ha för höga halter av förorenade ämnen. Vid förorening kan vattnet skada människor, djur och växter. Sverige måste ständigt jobba och förbättra reningen av vårt dagvatten.
Reningen av dagvattnet och på vilket sätt det ska ske är något som ständigt kan förnyas och förbättras. Idag renas dagvatten med hjälp av dammar och våtmarker och reningen kan bli bättre med hjälp av flytande våtmarker.
Syftet med denna uppsats har varit att ta fram mer information om flytande våtmarker och att sprida denna så att intresset och kunskapen ökar och förhoppningsvis även användningen av dem så att reningen av dagvattnet kan förbättras.
Arbetet innehåller en litteraturstudie och resultat från intervjuer vilka bägge syftar att ta reda på hur en flytande våtmark fungerar, hur den är konstruerad, vilken typ av skötsel den kräver, vilka växter som fungerar bäst, hur de renar vattnet och hur man skulle kunna använda sig av dem här i Sverige.
I arbetet finns det information om när en flytande våtmark renar som bäst, vilka typer av växter som bör användas och vilka typer av stommar det finns till den flytande våtmarken.
Skaftslamkrypa (Elatine hexandra) i Bolmen, utbredning, tillväxt, reproduktion och styrande faktorer
The plants in the genus Elatine are characteristic for oligo and mesotrophic lakes. This study focuses on Elatine hexandra one of the four species in Sweden. It is stated as vulnerable by the National Environment Agency and a conservation plan with guidelines to preserve the plant in Sweden is under preparation. There have been a few previous studies investigating this plant in other countries but this is the first one for Sweden. The aim of this study was to investigate the distribution, growth and reproduction of E.
Effekter av upphörd hävd i Lurö skärgård : Har diversiteten av kärlväxtarter förändrats?
One of the main reasons for the massive loss in plant species diversity is the fragmentation of habitats. In Europe, open pastures and meadows are the habitats going through the most changes during the 20th century, according to the agricultural changes. In this study vascular plants were invented at five different islands in the Lurö archipelago, Vänern, Sweden. The aim of the study was to sort out whether the diversity of plants has gone through any changes in abandoned managed grasslands compared to continuous managed grasslands. The aim was also to study if a change in the landscape has made any differences for the species development or decline.
Outnyttjade resurser inom park- och naturvård
As a small and land scarce country, effective waste management is ofoutmost importance in Singapore. In this study the production of biogasthrough anaerobic digestion from the organic fraction of municipal solidwaste (OFMSW) was compared to incineration of the waste. At the momentalmost all of the OFMSW in Singapore is incinerated. Three differentscenarios were compared to the reference scenario (incineration): one with alarge scale biogas plant that can treat half of all OFMSW in Singapore, onewith a medium scale biogas plant about 15 times smaller than the large oneand one with a small scale biogas plant that can treat waste from e.g. ashopping center or a food center.By using life cycle assessment (LCA) the different scenarios were comparedin terms of global warming potential (GWP), acidification, eutrophication,energy use and land use.
Utvärdering av vattenrening och identifiering avförluster m a p energi vid Bravikens pappersmaskin 53
This Master degree project has been performed at the Braviken paper mill on papermachine 53 (PM53) which produces newsprint paper. The current economic situationhas contributed to declining demand for newsprint, which means it is extra important tobe competitive by high energy efficiency. Particularly as energy prices are expected torise when the economic growth returns.One way to increase energy efficiency is by reducing the water use in paper and pulpmills and consequently save energy through reduced heating of water. The thesis's maintask is to evaluate whether a water purification plant (microflotation plant) forpurification of process water in PM 53 is profitable. The microflotation plant enablesreuse of warm process water instead of losing the energy to receiving waters.
Kostnadsutveckling i anläggningsprojekt. En studie av processen före byggstart i två vägprojekt.
A clean and affordable energy source for cooking is deficient in developing countries. People rely on fuels that contribute to environmental, social and health problems.Biogas is an alternative energy source and an increased investment in small-scale biogas production can in several developing countries be found. Several projects have started to use the technology in developing countries because of the benefits with biogas. Some cases in the establishment of biogas plants have succeeded and some have not. The study is a literature review supplemented by two field studies.