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276 Uppsatser om Reactive phosphorus filters - Sida 4 av 19
Sjöars känslighet för klimatförändringar ? vilka faktorer påverkar?
The Earths climate is changing at a higher rate, i.e between 1861 and 1994 the annual mean temperature in Scandinavia increased with 0,68º C and according to recent climate models the annual mean temperature is likely to rise with another 3º C during this century.A warmer climate in many ways is associated with changing conditions for lake ecosystems. An expected higher water temperature and a stronger summer stratification of the water column increases the risk of anoxic conditions at the lake bottom. Thus anoxic conditions are likely to cause a phosphate leakage from the sediment, i.e. a higher internal loading of phosphate.In this project, the extremely warm summer of 2002 has been used as an example for a possible scenario for a future climate. By comparing levels of phosphorus in the summer of 2002 with a ten-year median value, a phosphorus related sensitivity to climate change has been analyzed for 55 Swedish lakes.
Våtmarker för näringsretention i Lillån : var bör de ligga och vilken effekt kan vi förvänta
Construction of wetlands in the agricultural landscape may reduce nitrogen and phosphorus
transfer to streams, thereby reducing the eutrophication of lakes and seas. The agriculturalstream Lillån, a tributary to stream Sagån, ends up in Lake Mälaren and is transporting large amounts of these plant nutrients. The aim of this study was to estimate how hypothetical wetlands of different size and location may reduce nitrogen and phosphorus load from stream Lillån. Estimated nutrient retention in several small wetlands was compared to retention in a single large wetland based on existing data from the agricultural stream and from a nearby smaller stream. Retention in the stream was suggested to decrease along with the nutrient concentration in the water.
Metodik för bestämning av åkerdikens status : fallstudie av ett dike i Munktorps socken
Agricultural drainage ditches are links between fields, lakes and oceans, having the potential to transport e.g. sediment and nutrients. When in a good condition, drainage ditches can act as sinks for e.g. phosphorus and sediments and prevent eutrophication downstream.
The aim of this study was to determine the condition of one agricultural drainage ditch and to come up with suggestions for appropriate measures. The aim was also to determine
which of the ditch?s properties that were possible to evaluate visually, which processes they represented as well as which properties required complementary physical analysis.
This in order to contribute to the work of developing a method for determining the status/condition of agricultural drainage ditches.
Analys av oljedimavskiljare
3nine has developed oil mist separators for the manufacturing industry. They are used in factories and workshops in Sweden as well as many other countries. The basis for this thesis is to investigate the performance of these separators in applied environments under different circumstances and to find factors that influence the performance. It has been shown both theoretically and in laboratory environments that the sizes of the particles in the oil mist influences the performance of separation. This is to be verified under applied circumstances as well.The separators also have in most cases, after the centrifugal separation, HEPA-filters mounted that separates the remaining oil mist.
Fånggrödor i Norra Östersjöns vattendistrikt
70 % of the lakes and waters in the water district of northern Baltic Sea do not reach the
requirements for good ecological status. This is mostly due to eutrophication caused by a too
high deliverance of nutrients from agricultural land or effluents. Losses of particulate
phosphorus through water erosion contribute to a great extent to this eutrophication. In the
action plan for the water district cover crops are mentioned as a measure for reducing losses
of phosphorus from arable land. This paper reviews the possible effect of cover crops in the
water district and discusses what crop that would be most suitable.
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.
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.
Synoptisk provtagning i vattendrag med eutrofieringsproblem : En studie för att identifiera områden för prioritering av åtgärder
In Halland, agriculture is the major source of eutrophication of water. In the study, synoptic sampling were performed in the three watercourses Nyrebäcken, Skintan and Vinån all located in the county of Halland. Sampling occurred during the period February to May on three occasions with different flow rates: high, low and base flow. Samples were taken in the mainstream and tributaries with intention to show how big the impact of eutrophication it is in the water and to assess the impact of the tributariesThe results show that all watercourses are affected by eutrophication. Nyrebäcken has the highest concentrations of nitrogen and phosphorus in the mainstream, then Skintan and last Vinån.
Miljöpåverkan av äggproduktion : En jämförelse mellan Lilluns ägg och andra svenska äggproducenter
The purpose of this report was to compare Lilluns egg production with other Swedish egg producers based on the flow of nutrients (nitrogen, phosphorus and potassium) in the egg production systems. The main focus in the report was the utilization rate of the forage and the excess of nutrients per kg egg. Additionally, the purpose was to identify the environmental impact from Lilluns egg production and compare the results with other egg producers. The inflow of nutrients associated with forage and poultry was compared with the nutrients that were exported from the production. All of the egg producers in this study had an excess of nutrients.
Självförsörjande elgenerering : Kan Orust bli självförsörjande på förnybar el?
Orust Kretsloppsakademi is a nonprofit organisation, with a goal of annually generate the same amount of electrical energy that is consumed. Orust is an island on the west coast of Sweden, north of Gothenburg. The population of 15 000 reaches 40 000 during summer, due to the large amount of vacationer. The total electricity demand is 174 GWh a year with a maximum power need of 32 MW. This report presents an analysis for the plausibility of their plan and from a power system stability perspective, the effects on the electrical grid.The conclusion is that the restraints for development of power generation from wind, solar and wave generation, are the power systems capability to transfer power, primarily in the transformers of the grid.
Återvinning av näringsämnen från hushållsspillvatten med omvänd osmos
Hammarby Sjöstad is a new district in Stockholm with high environmental standard. Stockholm Water Company evaluates a local wastewater treatment plant with cutting edge technology. The first step is an experimental treatment plant (Sjöstadsverket) with four parallel lines of treatment, each with a capacity to treat wastewater from 150 persons. Within the membrane technology subproject the possibility of using reverse osmosis (usually called RO) to regain nutrients is examined.Reverse osmosis separates the incoming water in a clean permeate and a concentrate that, as the name indicates, is a more concentrated version of the incoming water. Using this method in wastewater treatment, a solution high in nutrients can be obtained without the use of chemical precipitation agent and with no production of sludge.
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.
Bedömningsgrunder och reningskrav för avloppsreningsverk, 25-2000 pe, i Laholms kommun
The aim of this project was to look into ten small sewer systems in the municipality of Laholm, in Sweden, in order to work out common assessment grounds for them. The sizes of the systems for purification of wastewater were within the range of 25 to 2000 population equivalents. Our method was to study literature, the laws and regulations applicable and the files at the municipality. The conclusion is that every sewer system is different and every situation is unique. We concluded that based on laws and assessment grounds sewer systems equal in size and pollution load ought to have similar demands attached to them.
Mineralämnen i fullfoder : studier på 20 mjölkkogårdar i Halland
In 2003 the recommended phosphorus allowance for dairy cows in Sweden was lowered approximately 10 %. For a cow at a production level of 35 kg ECM it decreased from 0,40 to 0,36 % of dry matter. To investigate if the decrease has been implemented at farm level, analysis of following minerals; P, Ca, Mg, K, Na, S, Se, Cu, Mn and Zn was performed on the TMR at 20 farms in Sweden in the summer of 2004. The purpose was to describe the actual allowance of different minerals as compared to the new recommendations. One hypothesis was that the decrease in recommended allowance of phosphorus would lead to the need of new mineral feeds on the market.
Optimerad styrning av kondensatorbatterier - Ny möjlighet att minska förluster med elektronisk brytteknik
Transmission of reactive power is well known to cause active power losses. Thus, newcomponents who can help minimizing these expensive reactive power flows are ofgreat interest to the power distribution companies. ABB Corporate Research hasdeveloped the first electronic power breaker. One possible application for thisbreaker is transient-free switching of capacitor banks. This could prove a usefuldistribution voltage complement to the switch-sync technique, mainly applied to transmissionvoltage level.