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323 Uppsatser om Nitrogen removal - Sida 4 av 22

Sedimentprovtagning av dagvattendammar som ett alternativ till flödesproportionell vattenprovtagning

Stormwater run-off from surfaces such as roads or rooftops is often polluted with heavy metals and nutrients. Many of these substances can cause great damage in biota if they end up in the recipient. In Sweden constructed wetlands and ponds for treatment of stormwater are frequently used, since research has shown that these treatment ponds are reducing stormwater pollution considerably to a low cost. The knowledge of these pollutant removal mechanisms and how follow-up and assessment of the ponds should be performed is still limited.To determine the pollutant removal efficiency of the stormwater ponds it is recommended that flow-weighted water samples are collected from both the inflow and the outflow of the pond. This method demands considerable resources of time and money for installations and analysis.

Bättre enskilda avlopp i Sigtuna kommun : möjligheter för bebyggelse i Odensala socken

There are around 855 000 on-site sewage systems in Sweden and some 1 800 of these are located in the municipality of Sigtuna. The Sigtuna local authority has set the goal that all sewage systems with insufficient function should be improved before the end of year 2010. A malfunctioning on-site sewage system may cause three main problems: spreading of diseases, discharge of eutrophicating compounds and wastage of resources. The municipality strives to reduce these problems already at the stage of granting permits for installation of on site sanitation systems. The municipality has recently adopted new guidelines, which demands certain minimum reductions for different compounds. The guidelines also state that it is preferred that neighboring house-owners cooperate in jointly built and operated sewage systems and that the system should be able to recycle plant nutrients.

Fordonsgas ur gödsel och vall

AbstractThe dependency of fossil fuels in the transport sector causes large emissions of carbondioxide. This problem can we reduce by using vehicle gas from digested solid manure and leftover of pasture. I have studied the potential for this in the county of Västernorrland. Thepurpose is to investigate how much vehicle gas that can be extracted.One central, large scale digestion and upgrade plant should be placed in Härnösand. Theamount of pasture and manure that is economical and practical available is enough to produce2,7-3,5 millions Nm3 vehicle gas.

Optimering av indunstningsprocess

The wastewater treatment plant at GE Healthcare's facility in Uppsala deployed a three step vacuum evaporator in 2007. The purpose of this was to pre-treat wastewater containing amines. The purpose of this thesis was to optimize thisprocess by reducing the amount of concentrate without releasing more nitrogen tothe environment and to examine if density could be used as a measurement of whenthe process should be ended.To create a foundation for optimization six test cycles were conducted with samples taken from all three steps. Both concentrate and condensate were tested as well as the incoming solution. Furthermore, the thesis has been expanded with a benchmarking part examining two different evaporators.

Vårvetesorters effektivitet i användningen av kväve under den huvudsakliga tillväxtperioden

Crop efficiency in utilizing available nutrients is an important factor in increasing produc-tivity and reducing the environmental impact of agriculture. Nitrogen is the nutrient that plants need in the largest quantity and wheat, along with maize and rice, is the world's most cultivated crop. In this work, the Nitrogen Use Efficiency, NUE, during the major growth period, HTP, of twelve different spring wheat varieties, were examined. The NUE was calculated as the product of uptake efficiency of nitrogen, UN, and the conversion effi-ciency of nitrogen to biomass, EN. The purpose of this work was to find if there are varietal differences in NUE and its components among the twelve varieties and to link a high NUE to specific characteristics of the varieties.

Miljödammars funktion som kväve- och fosforfälla samt som bevattningsdamm i Sölvesborgs kommun

A study was made on four environmental ponds in Sölvesborgs municipality. The reason forthis was to see if the ponds had fulfilled some of the questions that was mentioned in theproject ?Rädda Hanöbukten?. The questions were as following; do the environmental pondsdecrease the leakage of nitrogen and phosphorus into Hanöbukten, do the ponds decrease theuse of groundwater in Sölvesborgs Municipality and are there any restrictions on what thewater in the ponds is allowed to be used for. In order to answer these questions aquestionnaire was made and interviews were held.

Hydrolys av primärslam för förbättrande av biologisk fosforreduktion vid behandling av hushållsavloppsvatten [Hydrolysis of primary sludge for enhancement of biological phosphorus removal in household wastewater]

Hammarby Sjöstad is a new district of southern Stockholm built with focus on reduced environmental impact by recirculation of materials and sustainability. The environmental goals aim to cut the water consumption by half and a separate storm water treatment. Thus, the wastewater will be more concentrated and will originate from the households only. The Sjöstad project includes the idea of a local treatment plant for the household wastewater. To evaluate this possibility, Sjöstadsverket, an experimental treatment plant was constructed.

Finns det något samband mellan stormusslors (unionoida) föryngring och utsläpp i närheten av dess levnadsmiljö? : en jämförelse mellan vattendrag i Västra Götaland

Common species of freshwater mussels may, like the freshwater pearl mussel (Margaritifera margaritifera) have a drastic decline in number and there is several reasons, like sedimentation, a decline of host fishes, introduction of alien species, nutrition leakages from agriculture and pollutants of medic drugs and poison. Ann Gustavsson made in the year of 2007 a study over rejuventation of freshwater great mussels in nine watersystems and considered that the rejuventation within the populations were all along the line poor. This study orients from her work and points to determine if there is a connection between the poor juventation and pollution of nitrogen and phosphorous from industries and private sanitations. The study was performed with the software program ArcGIS9.2 to take out drainage areas for the concerned habitats and contact was made with the concerned authoritys. When it comes to supervision of private sanitations is it the countys and for industries is it the county administrative board.

Källsorterade systems påverkan på avloppsreningsverk : växthusgaser, energi- och resursanvändning i modellstudie

The aim of this study was to evaluate the effects on a simulated wastewater plant regarding GHG emissions and use of energy and resources when implementing source separated wastewater systems. The effects were studied for different restrictions of effluent quality and for different temperatures on the influent. The simulation model BSM2G calibrated for Käppala wastewater treatment plant was used. The task was executed by simulating nine different scenarios with an increase in influent load from new connections equivalent to 3, 10 and 30 % of the present connections. These new connections were served by conventional, urine separated or black water separated systems.

Kan mjölkkors utnyttjande av vallprotein bli bättre? : utfodringsstrategier och konserveringsmetoder

The purpose with this literature study was to investigate the possibilities for improvement of forage protein in dairy cows with focus on feeding strategies and conservation of forage protein. The utilization of forage protein in dairy cows is often not that efficient as it could be. The feed crude protein consists of both true proteins and non protein nitrogen. The digestion of proteins in the rumen depends on the protein degradation rate and the ability of the microbes to synthesize microbial protein. The microbes need a balance between carbohydrates that provide them with energy and proteins that are degradable in the rumen.

Förändring av nitratläckage och växtproduktion från låglänt jordbruksmark vid en ny reglering av vattennivån i Mälaren

The water level of Lake Mälaren has been regulated since the 1940?s. A recentinvestigation suggests that the current regulation needs to be adjusted in order toprevent a decline in water level, salt water from infiltrating from Lake Saltsjön,and risk of floodings. In addition to these preventions, the new regulation couldpotentially effect the natural environment and agriculture practices in the lowlands that surround the lake. The new regulation proposal calls for an increase invariations in Mälaren?s water level during seasons, while the annual mean waterlevel will remain the same.

Bevattning av lagrat virke vid svensk skogsindustri : omfattning och miljökonsekvenser

Most of the saw and pulp industries have stored wood nearby their production, the main reason is to have a continuous wood flow to the production. Wet storage of wood is of great importance to keep the wood quality. Without water sprinkling the risk of drying outand decomposition through biological activity increases significantly and will result in a negative effect on future production and quality. One drawback of wet storage of wood is the leaching of chemical substances into the surrounding recipient. The log yard run-off contains phosphorus, nitrogen, phenols and organic substances. These substances can cause problems for the surrounding environment. The main objective of this project is to gain an understanding of the wet storage used by the Swedish wood industry and estimate the environmental consequences that run-off water will have on the recipient.

Hygienisering av torkat bioavfall

The main project Dry preservation of food waste from households includes a new technique concerning drying and storage of dried biowaste as well as a study of the sorting of household waste and further usage of the dried biowaste. A question asked in the project is, can the dried biowaste be used as a soil amendment? If organic waste is used as a soil amendment, precaution concerning hygienic safety risks has to be accounted for. The objective of this M. Sc.

KVÄVEUPPTAG HOS FÅNGGRÖDORNA VITSENAP OCH OLJERÄTTIKA VID OLIKA ETABLERINGSMETODER :

The object with this thesis is to evaluate which of the catch crops oil radish and white mustard in combination with establishment method, give the most effective nitrogen uptake. The main purpose of the catch crops is to reduce leakage of nitrogen. They are sown after the main crop and killed before the next crop. In Sweden the farmers gets subsidies to establish catch crops. The thesis is limited to the trail L3-9010 sited at HS- Malmöhus, Borgeby Gård, 237 91 Bjärred, Sweden, 2007. Only treatments with oil radish, white mustard and the reference treatments were studied.

Övergödning i Laholmsbukten  En studie av Laholmsbuktens övergödningssituation

This essay discusses the Laholm?s bay and its eutrofication problems. The question of issue is: Have the efforts to limit the eutrofication in the Laholm?s bay been effective? What is the local actor?s opinion whether the measures have been effective or not? What efforts have been made to prevent the leakage of nutrients from fields and forestland? The Laholm's bay is located in the south part of the Swedish west coast. The problem was noticed in the 1960´s by local fishermen that experienced a lack of catch.

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