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203 Uppsatser om Nitrogen - Sida 12 av 14
The legacy of the mill : a metal polluted forest soil in Gusum
Soils in a metal contaminated site on Stångberget in Gusum in southeastSweden were investigated and compared to relatively unaffected soils a fewkilometres away. Pollution came from historical release of untreated flue gasesfrom a brass mill. The objective was to find information on how high the metalconcentrations are, if metals from the polluted soil affect the surroundings andif the metal contamination affects the microbial community. The soil wasinvestigated using several different methods, such as field XRF measurements,chemical analysis of metal, carbon and Nitrogen content, pH, acid neutralizingcapacity, texture, soil depth, field leach tests, sequential extraction and microbialfunctional profiles. The study showed that copper and zinc concentrationswere above Swedish Environmental Protection Agency guidelines for lesssensitive land use on the entire investigated area.
Potatisens specifika vikt och kokegenskaper med hänsyn till odlingsplats och sort :
The boiling properties are an important quality issue of the potato. In order to obtain adequate boiling properties the growth of the potato needs to be controlled and interrupted at the right time. However, it is difficult to determine when to stop the growth. Specific gravity can easily be measured and can sometimes be used as a tool for estimating the boiling properties.
This report discusses different aspects of the specific gravity of the potato and how it can be used as a tool to determine the appropriate time for vine killing.
Potatisens specifika vikt och kokegenskaper med hänsyn till odlingsplats och sort :
The boiling properties are an important quality issue of the potato. In order to obtain adequate boiling properties the growth of the potato needs to be controlled and interrupted at the right time. However, it is difficult to determine when to stop the growth. Specific gravity can easily be measured and can sometimes be used as a tool for estimating the boiling properties.
This report discusses different aspects of the specific gravity of the potato and how it can be used as a tool to determine the appropriate time for vine killing.
Resurseffektiv kvävereduktion genom nitritation
Resurseffektiv kvävereduktion genom nitritationProblematiken med övergödning i våra akvatiska system har lett till hårdare krav på kväverening vid våra reningsverk. En rejektvattenbehandling har visat sig vara ett bra alternativ för att utöka kvävereningen. Vid Nykvarnsverket i Linköping renas avloppsvatten och sedan 2009 finns en SHARON-anläggning i drift. SHARON står för ?Stable High rate Ammonia Removal Over Nitrite? och är en kvävereningsprocess för rejektvatten utvecklad av Grontmij i samarbete med Tekniska universitetet i Delft.I denna studie har SHARON-processen i Linköping undersökts.
Konstruktion av en fotobioreaktor för odling av alger : ett småskaligt försök
The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.
Methane emission from nitrate-treated tannin rich feed for cattle in Vietnam
In developing countries such as Vietnam the population consumes more animal products for example milk and meat than before which requires greater livestock production. Ruminants contributes to more methane emission which creates a dilemma between food production and its environmental impact. By feeding ruminants with nutritive crops which humans can not assimilate the animal performance will increase in terms of better growth and milk production without inpinging on food that can be consumed directly by humans. Increasing animal performance reduces methane emission in terms of amount of methane in kg-1 milk and meat which today is much greater in developing countries than developed countries. The aim of the study was to investigate tropical tannin-rich legumes for their potential as a feed supplement for ruminants made in vitro.
Gestaltningsförslag för Norbyvreten : från kvarterspark till stadsdelspark
The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.
Askåterföring i Jämtland : biobränslets och askans innehåll av tungmetaller relaterat till markernas geokemi
Using biofuels from regeneration cuttings is becoming more common in Sweden. Ash from the combustion of biofuels contains many valuable nutrients and base cations. The Swedish Forest Agency recommends that ash should be recycled to clearings where biofuels have been removed, to avoid future impoverishment of Swedish woodlands. In Jämtland, in northern Sweden, a large quantity of biofuels are taken out from cuttings but ash recycling has not yet been tried. The aim of this thesis was to examine the conditions for ash recycling in Jämtland regarding to soil chemistry and heavy metal content in soil and biofuels.
Analys av framtidens system för hantering av avloppsvatten och matavfall i Eskilstuna
Wastewater treatment is increasingly controlled by the Swedish environmental quality objectives, adopted by the Swedish parliament. There is a need for a sewage system that can fulfill stringent requirements concerning the environment, recycling and resource use and hygiene. Additional environmental aspects in recent years are the impact of climate change, new knowledge about the effects of pharmaceuticals in water, the need for improved wastewater treatment and increased recycling of nutrients to agriculture. This report has, from a future scenario of the year 2050, analyzed seven different systems for wastewater treatment and treatment of compostable biowaste from households in Eskilstuna. A future scenario was chosen based on that within a forty year period new challenges may arise which can result in higher demands on sewage treatment than those we see today. Another reason why the future scenario was established is that changes in wastewater treatment systems are slow to establish. The analysis is mainly focused on the economical aspects but environmental aspects such as emissions to receiving waters and potential recycling of plant nutrients has also been evaluated briefly.
The bioavailability of soluble oxalates in stir-fried silver beet leaves
The prevailing food and energy crisis of the world, due to the declining reserves of fossil energy and a never ending rise of consumption, forces us to look into new fields to supply our energy demand. The boom of bio energy is criticized, as food crops are used to provide biodiesel and ethanol and the volumes are ridiculously small to supply world demand. Algae are one of the world?s oldest life forms and exist in many different phyla, providing a great variety to choose from, for different purposes. Cultivating microalgae offer a way to produce energy at great volumes without competing with food production and at the same time the algae offer a way to use our expensive nutrients in a more efficient way, besides this the algae are carbon dioxide neutral since their carbon source can be supplied by the atmosphere and the additional energy required can be supplied by algal oil or other renewable sources.
Samhällsekonomisk analys av ett djupförvar för använt kärnbränsle i Forsmark :
This thesis investigates the socio- and environmental economic effects of a deep repository for spent nuclear fuel in Forsmark in the municipality of Östhammar. I seek to show the general picture but focus on the effects on employment, environment and income. Cost-benefit analysis is used to investigate the differences in utility between a scenario with and a scenario without a deep repository in Forsmark.
Most of the possible effects can not be valued and many can not even be quantified with the data available today. Therefore this thesis has a bit of a ?preliminary study character? and seeks to show what we know today and what needs to be further investigated when available data allow it.
The costs that could be valued are noise from the traffic during the period of building and emissions of carbon dioxide and Nitrogen oxides from the transportation of rock masses during the building period.
Typhas inverkan på reningsgraden av TKN, BOD5 och COD i en anlagd rotzonsvåtmark i pilotskala.
Detta examensarbete är utfört på plats i Lajaedo, Brasilien och i anslutning till Sanitário de Lajeado ? RS, Brasilien, mellan januari till maj 2010. I samband med denna rapport utfördes två andra examensarbeten inom samma områden. Det är menat att denna rapport skall ligga till grund för framtida projekt och beslut om utökad lakvattenrening.Lajeado ligger i södra Brasilien ca 100 km från atlantkusten. 10 km utanför Lajeado ligger en ung avfallsdeponi på ca 15 000 m2 till ytan med tillhörande lakvattenrening med ett utjämningsmagasin, en syrsättningsbassäng samt sedimentering.
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.
Kvantifiering av föroreningstillskott från dagvatten inom skyddsområdet för Göta Älv : en simuleringsstudie med modellen SEWSYS
The river Göta Älv reaches between Vänern and Gothenburg and is the main raw water source for Gothenburg that supplies about 700 000 people with water. To protect and maintain a high water quality, continuously samples and water analyses are made throughout the river. In 1998 a protection area was founded between surte and Lärjeholm where the raw water intake is. This was made to increase the awareness of the importance to protect the water. However, there is a lot of contribution of untreated stormwater to Göta Älv within the protection area.Göteborg Water and Sewage Works commissioned this thesis where two areas, Tagene industrial area and Kärra residential area, with untreated stormwater outlets within the protection area are studied.
Hydrauliken i Ångersjöns fosforfällor : bestämning av flödesvägar och åtgärdsförslag för optimal fosforbindning vid avloppsrening med reaktiva filter
Discharge of untreated wastewater leads to unnaturally high levels of Nitrogen and
phosphorus in rivers, lakes and the sea, which results in unbalanced ecosystems with
eutrophication and lack of oxygen. Part of the phosphorus in surface waters is coming from
on-site wastewater treatment from scattered households with unsatisfactory purification.
Blast furnace slag is a by-product from iron production, and has in laboratory trials showed good phosphorus binding capacity. To test blast furnace slag as a reactive filter media for phosphorus separation in a full scale experiment, a wastewater treatment plant has been built behind the picnic area at Ångersjön alongside the road E4 in central-eastern Sweden. The plant contains two parallel lines, one with blast furnaces slag and the other with Filtralite-P as phosphorus sorbent. Both filters have showed decreasing phosphorus purification effect with time in spite of a low wastewater load.