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697 Uppsatser om Nutrient reduction - Sida 1 av 47

Närsaltsdosering till luftad damm : en åtgärd för ökad TOC-reduktion hos Skoghalls Bruk luftade damm

In the process of making carton boards into Skoghall Mill, are great quantities of water being contaminated. This water has to be treated before it is possible to release into the recipient, Kattfjorden. One of the contaminations that is important to extract from the wastewater, is organic carbon (measured as TOC-total organic carbon) because microbiological breakdown can lead to the bottom becomig free of oxygen.The wastewater treatment at Skoghall Mill is done through an external wastewater treatment that is located at the factory. The biological treatment (aerated lagoon) is a 140 000 m3 water pool with surface aerator, which is give oxygen to the water. In the lagoon live microorganisms who performs the biggest part of the TOC-reduction.One problem with the lagoon is that the treatment of TOC is considerably worse during wintertime than during summertime.

Magasin för lagring av vatten och växtnäring

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Cultivation of Chlorella vulgaris in nutrient solution from greenhouse tomato production : a possibility to reduce nutrient levels and produce commercially interesting metabolites

The idea of using algae in different areas and exploring its possibilities is nothing new. Already in the early 1950s microalgae was explored as a possible food resource because of its high protein content. Lately there has been an increased interest in its potential for industrial use. Wastewater treatment is a possible use of algae since the algae grow well on the nutrients present in the water. This offers the possibility to grow algae for Nutrient reduction and use the biomass for energy or animal feed since many alga species has a good nutritional value. Approximately 800-1000 m3 water is applied per 1000 m2 of greenhouse area during one season in a tomato production.

Exosomes as a potential mechanism of intercellular spread of prion protein

Structural rationalizations and regionalization of the agricultural sector in Sweden has lead to unevenness in thedistribution of plant nutrients. Nutrients are lost from crop producing farms as harvest products are sold, whilefarms with animal production often have manure in excess of their needs. In addition to this the retention ofwater and nutrients in naturally occurring wetlands has decreased due to a reduction of wetlands in number andsize in the agricultural landscape. This increases nutrient levels in agricultural run-off and causes eutrophicationas well as nutrient losses from arable soils. One potential solution to both problems would be to store nutrientrichsurface water from agricultural areas and use it for irrigation of agricultural crops.

Rening av avloppsvatten med anaerob membranbioreaktor och omvänd osmos

This master's theses was carried out on assignment from Stockholm Vatten AB as a part of a project developing new waste water treatment techniques. The goal of the theisis has been to evaluate an anaerobic membrane bioreactor for treatment of waste water from Hammarby Sjöstad. The bioreactor has not been heated and the main interest has been to study the gas production, power consumption and the reduction of organic matter and nutrients.The system has been completed with a reverse osmosis unit and a total of four batch runs have been made with good results. The use of reverse osmosis allows nutrient in the waste water to be reintroduced into circulation as the reverse osmosis concentrate can be used as crop nutrient.The membrane unit is of VSEP ("Vibratory Shear Enhanced Processing") type and an extensive membrane test has been conducted. This so called L-test helped determine the most suitable type of membrane for the system to allow a higher ±ux and thus lower power consumption.

Referensvåtmarker för uppföljning av växtnäringsretention i anlagda våtmarker

One of the environmental problems today in seas, lakes and streams is eutrophication. This is often caused by nutrients such as phosphorus (P) and nitrogen (N) that leak from agricultural areas. A measure to partly prevent the nutrient discharge is to construct or restore wetlands.In order to control the efficiency of Nutrient reduction of existing wetlands in the county, the administrative board in Västra Götaland wants to find different criterias for reference wetlands. These reference wetlands should represent other wetlands and be used in future evaluations of reduction of nutrients and design of constructed wetlands. According to the administrative board in Västra Götaland the reference wetlands should have a catchment area of about 50 hectare consisting of at least 70 % arable land, to represent wetlands created to remove nutrients.

Massbalansmodellering av fosfor i ett åländskt kustområde : en utredning om lokaliseringen av Lotsbroverkets utloppsledning

This report is commissioned by the Water and Sewage Agency in The City of Mariehamn, Åland. The basic aim is to investigate positive or negative effects of a relocation of the sewage pipe from a wastewater treatment plant, Lotsbroverket. The environmental licence of Lotsbroverket is to be revised and The Environmental Appeal Board at Åland?s Government and Administrative Board has made demands that several possible locations in an outer water area should be examined. The present location of the sewage pipe is in Svibyviken, which has been classified as an ?inner water area?.The objective of this work is to study to which extent the nutrient loading from Lotsbroverket influence the environmental conditions in Svibyviken, and to investigate the suitability of different locations of the wastewater pipe from Lotsbroverket.The way a coastal area looks, i.e., its morphometry, determines to a large extent its ecological characteristics.

Where has the fertilizer gone? Closing the nutrient budget for a eucalyptus fertilization experiment in southern China

An increasing demand for wood products in China has resulted in large areas invested in fast-growing tree plantations of eucalyptus. Eucalyptus plantations are often associated with an intensive management including fertilization. By understanding the effects of fertilization and where in the ecosystem nutrients are accumulated a more sustainable forest management could be achieved. In this study, a nutrient budget including all biomass and soil components was created for Eucalyptus urophylla. The examined nutrients were nitrogen, phosphorus and potassium.

Is goat milk a better milk replacement to piglets, rat pups and foals than cow milk is?

AbstractOne opinion among people who are experienced in hand rearing newborn mammals is that goat milk is more suitable than cow milk if the young needs a milk replacer. The purpose of this literature review was to find out if there is scientific evidence that goat milk is a better milk replacer for piglets, rat pups and foals than cow milk. The milk is essential for the newborn animal, as its only source of nutrition until it has learned how to eat solid food. In this literature review, the composition of goat milk and cow milk is compared with the nutrient requirements after birth in piglets, rat pups and foals. The nutrient requirements and the milk composition are partly determined by the newborn mammals activity level and suckling frequency, which also is described.

Jordbrukets påverkan på Östersjön : en jämförelse av indikatorer för att beskriva näringsbelastningen

The Baltic Sea, due to its special conditions, is a unique and vulnerable marine environment. There are many pressures that have an impact on the sea and one of the major problems is the extensive flow of nutrients from land. The most visible effect of the supply of nutrients is the annual algal blooms. One of the main sources of nitrogen and phosphorus supply is agriculture. Nutrient losses from arable land have been increasing as agricultural production has intensified. At the end of the twentieth century an increased awareness of these problems led to the formation of organizations such as HELCOM and Baltic 21.

Vingårdar i Sverige! : farligt för miljön?

The future climate of Sweden is expected to become warmer in the future. This would be beneficial for vineyards and may lead to a greater area being allocated for wine production. The environmental impact concerning eutrophication from Swedish vineyards has not been evaluated before. In this study nutrient balances are constructed for four Swedish vineyards with the goal to estimate the out and in flows of nutrient in the systems for the year 2010. Interviews with focus on farming practices undertaken during the year are conducted with the farmers.

En studie av retentionen i floden Oder och dess avrinningsområden, Polen.

Nutrient enrichment is the main cause of the increasing eutrophication process in the Baltic Sea during last century. A prerequisite counteract this process the load of nutrients to the Sea must be investigated. The large contribution of nutrients to the Sea is caused by emission from the rivers within the drainage basin. For the total emission of nutrient into the Sea the retention process in the rivers has big influence. This process in the river system has been assumed as a not important part of the nutrient cycle.

Optimerad hygienisering vid kompostering av avloppsslam

The aim of this study was to in laboratory experiments investigate how addition of urea, ECOX and structural materials can optimize sanitization during composting of sewage sludge. Today we strive for a sustainable society and the importance of closing the nutrient loop increases. It has therefore become even more important to safely reuse plant nutrients from human excreta to agricultural land. Partly because it increases the sustainability of society as the world's supply of many nutrients are finite, partly because it promotes human health, both by reducing disease transmission and by increasing Agricultural production. An untapped resource such as sewage sludge that is rich in nutrients and humus-forming materials could replace parts of the commercial fertilizers used in Sweden today. owever, sewage sludge contains undesirable substances such as heavy metals and drug residues, and pathogenic microorganisms.

Safe retrieval of nutrients to improve food security

Safe retrieval of nutrients from human excreta to fertilize crops in order to gain adequate yields will increase food security and sustainability in agriculture areas with nutrient-poor fields. Safe and nutritious food will meet the dietary needs of the individual which promotes public health and the ability of an active life. Human excreta should be considered as a resource instead of being assumed as waste. Human faeces and urine is excellent fertilizers which may close the nutrient loop if utilized properly. However, sanitation of the excreta is required to prevent disease transmission by reducing the content of gastrointestinal pathogens such as bacteria, viruses and parasites. The objective of this study was to in small scale evaluate the sanitation in a combined liquid compost and urea treatment by monitor the inactivation of bacteria and viruses at the combination three start temperatures, 45, 40 and 35 °C, and three additions of urea, 0.5, 0.75 and 1 % and reference, 0 % urea addition.

Kärnkraft : Ett arbete för drifttekniker?

The gas turbines in the Swedish secondary reserve are reaching the end of their technical lifetime, hence alternative solutions need to be considered. One of the solutions thought to have the greatest potential is the use of so called consumptionreduction. By entering contracts with large consumers, agreements are made to reduce consumption in the event of major disturbances in the power system and thus being used as a secondary reserve. This thesis investigates the feasibility of consumption reduction as part of the secondary reserve. This has been achieved by developing a requirement specification for the disturbance reserve and by studying the technical and economic potential for consumption reduction among a range of consumers.The technical potential for consumption reduction that fulfils the requirements for participating in the secondary reserve are on average 750 MW in SE 3 and 98 MW in SE 4.

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