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796 Uppsatser om Anaerobic digestion of organic waste - Sida 19 av 54

Landvinning : scenarier för efterbehandling och gestaltning av Aitikgruvan, Gällivare

Open pit mining creates huge amounts of tailings and waste rock deposits. Due to it's content of sulphide minerals, predominantly pyrite (FeS2), there is a risk of oxidation and formation of acid water containing heavy metals, known as Acid Rock Drainage (ARD). To prevent the process of oxidation, the tailings and waste rock have to be reclaimed. The most commonly used methods of reclamation are a coverage of water or soil. Mining also results in a large-scale interference in the landscape that will make an eternal change of its appearance.

Är kolrika jordar en källa till fosforläckage? : en sammanställning av data från 130 åkerjordar

Phosphorus (P) is an essential nutrient but a surplus could lead to eutrophication. Furthermore, the minerals used to produce the mineral phosphate is a non renewable resource. There are in other words several reasons to reduce the leakage of P and the agriculture is one important area to attend. The aim of this work has been to investigate if carbon-rich arable soils content contain more P than arable soils with low carbon content. Moreover it has been calculated if the carbon-rich soils could pose a risk of P leakage by comparing their delivery of P with the plant uptake. The work has consisted of compiling the results from former gathered and analysed soil samples of 130 Swedish arable soils. The fractions of P considered are water soluble P (Pw), ammonium lactate-extractable P (P-AL), hydrochloric acid-soluble P (P-HCl), organic ammonium lactate-extractable P (Porg-AL) and inorganic ammonium lactate-extractable P (Porg-HCl).

Förbehandling av skogsindustriellt slam för ett ökat metanutbyte vid rötning : En kombination av termisk och kemisk förbehandling

Vid tillverkning av massa och papper förorenas årligen 505 miljoner kubikmeter vatten som måste renas innan det släpps tillbaka till omgivningen. Vid reningen avskiljs först stora partiklar som sedan avvattnas och förbränns. Vattnet som blir kvar genomgår ytterligare en rening, varvid det bildas bioslam. Bioslammet innehåller mycket intracellulärt vatten, vilket gör det kostsamt och energikrävande att avvattna. Det är även sedan 2005 förbjudet att dumpa organiskt material, varför en mer ekonomiskt attraktiv behandling av slammet är anaerob nedbrytning.

ALK?RR - K?LLA ELLER S?NKA F?R V?XTHUSGASERNA METAN OCH LUSTGAS? Empirisk studie av v?xthusgasutbyte i kustn?ra alk?rr p? den svenska V?stkusten.

Due to global climate change and the rising levels of greenhouse gases (GHG) in the atmosphere, the interest for seeking solutions for mitigation has increased. While much attention has been directed towards technical solutions such as carbon capture and storage (CCS), biogenic carbon sinks has also garnered significant attention. Previous studies have shown that coastal ecosystems such as seagrass meadows and mangroves have a much greater capacity for storing carbon (C) compared to terrestrial ecosystems. That raises the question if other coastal ecosystems, such as coastal wetland forests, that previously haven?t been considered as blue carbon habitats also contribute to coastal carbon sink capacity.

Why does trehalose not improve autophagy in the SOD1G93A transgenic mouse model of familial ALS?

Amyotrophic lateral sclerosis is one of the major neurodegenerative diseases, causing an ascending paralysis that usually kills the patient within a few years from disease onset. The motor neurons show aggregates of proteins which in approximately 20 % of cases of the familial form contain mutated SOD1 protein. Trehalose is a disaccharide which has been shown to reduce protein aggregation and increase viability in cell models and alleviate symptoms in animal models of several neurodegenerative diseases associated with protein aggregation. When given orally to the SOD1G93A mouse model of ALS, trehalose failed to slow down the disease progression, which has led to questions about the uptake and distribution of the molecule in this mouse strain. The aim of this study was to investigate whether significant levels of trehalose reach the central nervous system of the SOD1G93A mouse after oral administration. This was performed by a trehalose assay of the brain of trehalose treated animals. A glucose assay was optimised for use in small samples of brain lysate after the digestion of trehalose into glucose by trehalase, and the difference in glucose concentration before and after digestion represented the trehalose level.

Skogen i barnlitteraturen : Kan den fungera som en källa till naturvetenskaplig kunskap?

The amount of various phosphorus (P) fractions in the sediment and the relationship between the amount of P and sediment particle size were investigated in a constructed wetland southwest of Linköping. Furthermore, the possible correlation between clay content in the sediment and distance from the inlet was investigated. Sediment samples were collected along three transects from the inlet to the outlet, with six samples in each transect. In order to measure the soluble P, an NH4Cl extraction was done. This was also analysed for total soluble P after oxidation with peroxodisulphate.

Det ekologiska steget : En studie kring hinder och drivkrafter för lantbrukares val att bedriva ekologisk livsmedelsproduktion i Östergötland

Denna studie syftar till att identifiera vad det är som driver eller hindrar lantbrukare i Östergötland att ställa om sitt lantbruk till ekologisk produktion och huruvida de identifierade påverkningsfaktorerna skiljer sig åt mellan konventionella och ekologiska lantbrukare. Semistrukturerade intervjuer med tre konventionella samt fyra ekologiska lantbrukare genomfördes för att undersöka deras erfarenheter. Respondenternas erfarenheter redovisas i sex identifierade teman; Gårdsspecifika förutsättningar, Ekonomi, Politik, Administration och regelverk, Miljö och hälsa samt Produktionsteknik. En jämförelse mellan de båda grupperna genomförs och det empiriska materialet ställs mot tidigare forskning. Resultatet av studien visar att skillnader mellan ekologiska och konventionella lantbrukares uppfattningar kring hinder och drivkrafter förekommer, men inte inom alla teman.

Sedimentation av lera och fosfor i en anlagd våtmark

The amount of various phosphorus (P) fractions in the sediment and the relationship between the amount of P and sediment particle size were investigated in a constructed wetland southwest of Linköping. Furthermore, the possible correlation between clay content in the sediment and distance from the inlet was investigated. Sediment samples were collected along three transects from the inlet to the outlet, with six samples in each transect. In order to measure the soluble P, an NH4Cl extraction was done. This was also analysed for total soluble P after oxidation with peroxodisulphate.

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.

PRODUKTINKONGRUENS: Vad som händer när en produkt i en produktkategori med negativ klang ges ett positivt attribut

Product development is essential for all companies that want to survive in competitive markets regardless of the characteristics of the product that the company sells. Companies that sell products within product categories which can be seen as bad, also need to develop their products in order to remain competitive. If these bad products add a positive attribute, for example that they get organic, a contradiction within the product arises and they get incongruent. This thesis investigates which effects that follow a launch of an incongruent product. The thesis also examines if these effects are affected by the strength of the brand under which the product is launched.A total of 240 respondents participated in an experimental study where product incongruity was manipulated for two different product categories, where one well known brand and one unknown brand were examined in each category.

Energikartläggning av avfallsförbränningen i Uppsala

Vattenfall Heat Uppsala runs the waste incineration plant in Uppsala, which produces district heating, process steam, district cooling and electricity. Vattenfall Heat Uppsala has decided to introduce an energy management system with the aim to increase the energy efficiency of the plant. The basis in such a system is to make an energy mapping.In this thesis an energy mapping has been performed at the waste incineration plant with the aim to identify and determine the size of energy flows. The investigated energy flows are used fuel, produced and used steam, produced district heating and cooling. Also the use of electricity to run the processes has been investigated.

Möjlig kvittblivning och eftermarknad av ridbaneunderlag - topplager

The aim of this study is to find information about what to do when riding arena footings are worn-out. Especially, the surface layer of riding arena footings is very interesting because of its importance of giving grip in every step for the horse, as well as shock ab-sorption. Generally, surface layers are containing several different parts in order to achieve desirable properties. These different parts can consist of organic material or in-organic material (mostly gravel). Gravel and many other materials in the top-layer are environmental friendly, and therefore, easy to get rid of.

Grön Marknadsföring = En Naturlig Strategi : Analys av Grön Marknadsföring i dagligvaruhandeln

Syfte: Att analysera hur dagligvaruhandeln använder sig av Grön Marknadsföring internt och externt för att positionera sig som ett miljövänligt företag på marknaden.Metod: En deskriptiv undersökning med primärdata i form av personliga intervjuer från de tre största aktörerna inom svenska dagligvaruhandeln.Teori: ?Green Marketing Activities at the Three Levels? har används som modell för att ta reda på hur de olika företagen arbetar med Grön Marknadsföring. Modellen är uppdelad i åtta områden och tre nivåer för Grön Marknadsföring.Slutsats: Samtliga företag vill ta ett miljöansvar, men två av tre ser sig även ha ett ansvar att informera och hjälpa kunder till ett bättre handlande. Två av de tre undersökta företagen är mer inriktade på att bygga ett ekologiskt varumärke medan det tredje företaget är mer inriktad på att upplysa om ekologi. Undersökningen visar dock att alla aktörer har undermåligt arbete med marknadsföringen i butik för att fånga upp kunders ekologiska intresse.

En grav är mer än bara en grav... En metodutveckling av tafonomi som redskap att förstå olika anläggningar med djur

This paper deals with a taphonomic study of contexts with osteological material of dog (C. familiaris L.) from the Mesolithic and Neolithic of Sweden and Zealand, Denmark. The general aim is to develop and test a method to try to understand the activity behind and define specific archaeological structures. My questions also regards to wether a taphonomic analysis of the material could be used to identify treatments as wrapping and contraction of the dogs, but also dismembering and other preparations of the body. The study focuses on the relation between the space of decomposition, disarti-culation of the joints, evidence of wall effect, cutmarks, weathering and signs of postdepositional arrangements.The analysis is based on contexts from the materials Hornborgasjön, Vedbæk, Skateholm I and II, Sjöholmen, Ertebølle, Bökeberg, Bredasten, Löddesborg, Bergsvägen and Röekillorna, dating from early Maglemose culture to Neolithic Battle axe culture.The analysis shows that a closer study of taphonomic processes can be used to identify different structures as graves, offerings, religious and non religious contexts or parts of animals, probably put into the ground as waste.

Bestämning av organisk halt i avloppsvatten med Total Organic Carbon (TOC)-analys

Kommunalt avloppsvatten innehåller stora mängder föroreningar bland annat organiskt material som påverkar organismerna i naturen. Reningsverken runtom i Sverige arbetar ständigt för att minimera utsläppen av föroreningar. Det är viktigt att kontinuerligt analysera vattnets kvalité för att kontrollera reningsverkets funktion. Total Organic Carbon (TOC) och Chemical Oxygen Demand (COD) är två analysmetoder som används för att mäta organisk halt i avloppsvatten. Från COD-analysen uppkommer farligt avfall som innehåller kvicksilver varför analysmetoden enligt EU-direktiv ska fasas ut.

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