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163 Uppsatser om Phosphorous removal - Sida 1 av 11

Optimering av biologisk fosfor och kvävereduktion i ett reningsverk för hushållsspillvatten

In connection with Henriksdals wastewater treatment plant (WWTP) a smaller plant is situated called Sjöstadsverket where new methods for wastewater treatment are tested and evaluated in different process lines. On one of the lines experiments with enhanced biological Phosphorous removal (EBPR), have been carried out to evaluate if it is a good alternative to traditional chemical phosphorus removal. This thesis evaluates the results from the experiments conducted during fall 2005.The incoming water from Hammarby Sjöstad consists of only household wastewater, which gives a wastewater with high concentrations of nutrients and organic carbon. This is partly positive, because one of the limiting factors for effective biological phosphorus removal is the lack of easily biodegradable organic carbon. The high concentrations of ammonium and phosphorus demand a high reduction to achieve the requirements of outgoing concentration.To optimize the process experiments with different recirculations and different aeration techniques have been made.

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.

Membranbioreaktorteknik- en framtida lösning på Lundåkraverket? : Membrane bioreactors- A future solution at Lundåkra wastewater treatment plant?

Membrane bioreactors (MBR) combined with biological phosphorous treatment (Bio-P) has been investigated if that could be an alternative to the future expansion with conventional active sludge treatment at Lundåkra wastewater treatment plant (WWTP) in the proximity of Landskrona, Sweden.The results showed that the surface demand in the biological treatment will be reduced with 67% with the MBR-alternative compared to a conventional activated sludge process. The nutrient removal in the MBR-solution was decreased or unchanged for nitrogen-, phosphorous- and organic parameters. However, the energy demand will increase with an estimated cost of approximately 1 million SEK annually. Moreover, the extra chemical consumption is estimated to cost 370 000 SEK annually.The disturbances caused by filamentous bacteria such as sludge dispersal could be resolved with MBR-technology because the membranes are not affected by these organisms. The Bio-P process combined with MBR-technology works if the wastewater recirculates from the membranes to an aerobic zone.In the proposal, there will be a new pre-treatment step, for instance hole screens.

Removal efficiency of perfluoroalkyl substances (PFASs) in drinking water : evaluation of granular activated carbon (GAC) and anion exchange (AE) using column tests, and the effect of dissolved organic carbon

Poly- and perfluoroalkyl substances (PFASs) are a group of environmental contaminants that have gained increasing attention due to their potential to bioaccumulate, environmental persistence and potential toxicity. PFASs have been found in surface water, sediment, air, soil, sludge and ice caps globally, as well as in wildlife and humans. Furthermore, PFASs have also been detected in drinking water, leading to raised concerns for human health, since drinking water is one of the most significant sources of PFASs for the general population. Conventional water treatment techniques have shown to be ineffective removing PFASs, highlighting the importance for further research to develop efficient removal techniques. The aim of this study was to investigate the removal efficiency of PFASs in water using two treatment techniques; granular activated carbon (GAC), type Filtrasorb 400®, and anion exchange (AE), type Purolite A-600. Additionally, the effect of dissolved organic carbon (DOC) on removal efficiency was studied.

The behaviour of foals before and after weaning in group

Weaning is a standard procedure at most studs, and the methods of weaning varies greatly. The method used at the stud in this particular study is supposed to decrease stress. The purpose of the study was to compare the behaviour of foals in group before and after stepwise removal of their mares. Standardbred foals with their mothers were kept in three different groups at pasture (12, 11 and 11 foals, respectively, mixed sexes). They had free access to silage and the foals were fed concentrate in a creep-feeding area. By the time the foals were 5 months old, the mares were stepwise removed from the pasture.

Reingsresultat, drifterfarenheter och kostnadseffektivitet i svenska våtmarker för spillvattenrening

I denna studie har funktionen hos sju anlagda våtmarker för behandling av avloppsvatten i Sverige jämförts över tid med avseende på avskiljning av kväve, fosfor och BOD. Syftet var att undersöka våtmarkernas långsiktiga funktion, skötselåtgärder och relaterade kostnader. Våtmarkerna (1,6 - 28 ha stora) har varit i drift olika länge, mellan 7 och 17 år, och befintliga övervakningsdata samt intervjuer med ansvariga för respektive våtmark användes som grund för studien. Resultaten visade att våtmarkernas reningsfunktion generellt sett varit god utan någon tendens till en försämrad funktion över tid. Våtmarkerna belastades med 1100 - 9900 kg N/ (ha·år) och avskiljde mellan 420 och 2400 kg N/ (ha·år), beräknat som ett medelvärde per anläggning.

Förändringar i markanvändning över tid och dess påverkan på vattenkvalitet

The EU Water Framework Directive has led that management follows the boundaries of natural catchments.The Swedish waters suffer from a nutrient overload that originates mainly from diffuse sources such as agriculture and the subcatchment of Hackstabäcken in Vallentuna Kommun, just north of Stockholm, has been chosen for this study because of its high nutrient load and because it has undergone obvious changes in land use through the years.In this study, the land use in 1902 is compared with the land use in 2011 in order to investigate if it has influenced the ability of the landscape to produce ecosystem services related to nutrient removal. These services will continue to be produced as long as the system is stable and resilient, but when landuse changes and manure from horses increases it will lead to disturbances that can convert a system from one regime in to a completely different one. That will result in loss, or degradation, of ecosystem services such as denitrification, phosphor sedimentation and adsorption, vegetation uptake and infiltration.The results of this study are based upon area calculations of landuse from old maps from 1902 and 2011. Through these maps it becomes clear that the forests in Hackstabäcken, has increased with 170 ha together with an urbanization of 311 ha, at the same time as wetlands and arable land has diminished and lakes has suffered from reductions. Wetlands have been reduced with 76 ha and the ones remaining are of insufficient quality from a nutrient removal perspective.Data from 1902 and 2011 regarding number of horses and bovines indicated a decrease in bovines and an increase in horses.

Skadegörelse klotter nedskräpning förbjuden : Graffitiborttagning som ikonoklasm

This essay concerns graffiti, and in particular graffiti removal regarded as iconoclasm.Graffiti is described as a visual symbol laden with both negative and positive values, and sometimes as a meaningful expression in the urban public space. One problem with graffiti as a field of study is the diversity of both the meaning of the term as well as the diversity of the phenomenon itself. Therefore I have defined the term graffiti as follows: words and images painted on public walls by a person usually in an unauthorised manner. Specific examples of graffiti and related phenomena are presented. Within the Swedish anti-graffiti discourse the pejorative term klotter (scribbling) is used to describe what I above define as graffiti.

Buskröjning längs skogsbilvägar : en produktivitetsstudie av två kättingslagor

To regularly remove woody vegetation along the roadside of forest roads is an important part of the road maintenance, since the vegetation binds moisture in the road side and, thus, the removal makes the road drying faster with results in improved bearing capacity. Vegetation removal also makes it easier to upgrade the road by material recycling from the ditch and, moreover, the visibility along the road is maintained.The aim of the study was to evaluate what type of chain flail is the best and most cost-effective for removal of different kind of woody vegetation along forest roadsides.Time studies were made on two chain flails when removing woody vegetation in three different classes; easy-, middle- and heavy shrub removal. The studied flails were one light and rather simple flail named Optimal M160 and a heavier and more advanced flail named Slagkraft H210. The removal was made according to Holmen Skogs? specification and the quality of the cleaning was measured by objective belt inventory.The productivity was higher with the heavy flail within all cleaning classes.

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.

Phycoremediation of pesticides using microalgae

Every year, pesticides are found in surface and ground waters in Sweden. Fungicides are in common usage and applied in high amounts against potato late blight. The present thesis examined the possible removal of four fungicides (metalaxyl, cyprodinil, propamocarb and mandipropamid) from water using the microalgae Chlorella vulgaris. Microorganisms are capable of decomposing a range of organic pollutants and the main focus in previously published studies has been on bacteria and fungi. Microalgae are mostly studied due to their high capacity in biosorbing heavy metals.

Reduktion av föroreningar i processvatten från en äggfabrik i Brasilien : Kväve- och fosforrening i anlagda våtmarker.

A water treatment unit consisting of two aeration basins, two settling tanks, a residence basinand a horizontal subsurface flow wetland were used to treat wastewater from an eggprocessing factory in Brazil. The aim of this paper was to determine the efficiency of thesystem in reducing nitrogen, phosphorus, BOD5 and TSS (among other parameters) andgetting a further understanding on different kinds of constructed treatment wetlands as well astheir nitrogen and phosphorus removal processes. The wastewater from the factory consistedof process water from manufacturing and water used for cleaning, no stormwater or sewagewater entered the system. Tests were taken three times a month from October 2013 ?til April2014.

Fosforgödslingseffektivitet i långliggande bördighetsförsök

Rapid population growth and the fact that phosphorous is a limited resource implies that the question regarding an efficient use of phosphorus is of great importance, and consequently,that the phosphorous use efficiency should be as high as possible. The view on phosphorous use efficiency, and how this is calculated, has varied over time. This has had great implications on what type of research that has been conducted, which have resulted in an inconsistency between the academic?s view on the subject and recommendations received by farmers. The purpose of this paper is to calculate the phosphorus use efficiency in the Swedish long term fertility experiments.

Mineraliska material som reaktiva filter för avskiljning av tungmetaller från dagvatten

Highly polluted urban storm water from e.g. highways can contain large amounts of heavy metals that may cause harm if they are discharged into recipients. To remove the heavy metals a possible low-cost method that does not require much maintenance, could be the use of reactive filters with filter materials consisting of industrial residues or other cheap mineral based materials. Dissolved metal ions are removed by reactive filters through the processes of ions binding to active sites on the surface of the filter materials, or by formation of insoluble precipitates.The ability of CaO-treated granulated blast-furnace slag, iron oxide coated sand, olivine and nepheline to remove seven heavy metals (Cr, Cd, Cu, Ni, Zn, Pb and Hg) from urban storm water was studied. Initially batch experiments were performed where the effect of pH, dissolved organic carbon (DOC) and dissolved ions on the adsorption efficiency was studied.

Lyviken : -bedömning av dagvattenkvalitet

AbstractStormwater is defined as rain- and melted water. Ludvika kommun had little knowledgde about the stormwater that reaches a specific recipient Lyviken. Therefore they intended to do an research of the stormwater that leads down to Lyviken. The aim with this study was to assess the quality of the contents in the stormwater based on pH, conductivity, phosphorous, nitrogen, bacterias, oil and one sample that meassured the value of several methals. Since the population has increased for decades, the area of hard surfaces and asphalts areas also has increased. This can increase the pollutions that finally ends up in the recipient.

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