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47 Uppsatser om Aerated pond - Sida 1 av 4

Utvärdering av Vissberga lakvattenbehandling

In connection with the admittance of the EC-directive (99/31/EC) in Swedish politic, through the constitution of waste depositing (2001:512) at year 2001, the rules about management the landfills and leachates tightened. At the landfill Vissberga in the municipality of Hallsberg, a leachate treatment plant was constructed just a year thereafter. This treatment plant consisted of an Aerated pond with a following land treatment and a willow cultivation to replace the land treatment during the summer. In this case the parameters, which were estimated as the most important to reduce, were iron and nitrogen. The iron would react with the oxygen-rich water in the Aerated pond and precipitate to ferric-hydroxide and than settle in a calm zone of the pond.

Interdependence between seed age and aerated steam treatment intensities

Aerated steam treatment is a modern and environmental friendly method for seed borne fungus sanitation, mainly used on cereals. The method involves exposure to heat and high humidity, factors which are known to induce a fast ageing of seeds, thus resulting in reduced storability. This thesis clarifies the interdependence between seed age and the aerated steam treatment intensities. Two studies were carried out in this thesis. In the first study the storage longevity of seeds treated with aerated steam was examined. The second study investigated the shelf-life of the pre-tests used to determine the aerated steam treatment tolerance of a seed lot, by testing the treatment tolerance of seeds aged prior to the treatment.

Lakvattenrening och kontroll vid deponier : granskning och sammanställning

If not purified leachate from landfills would cause damages on the environment. At most landfills in Sweden local treatment of leachate is achieved, at the rest the leachate is transported to sewertreatment. While no comprehensive legal provisions for discharge exist in Sweden there is a difference in discharges between the installations for landfill. If no comprehensive legal provisions is produced guidance must improve.Treatment of leachate and self monitoring system at fifteen installations in Sweden has been studied and compared. A study of literature about different treatment solutions has also been performed.

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.

Vindpark Vänern : Fundamentteknik och Logistik

An analysis of a specific application of anaerobic wastewater treatment at a pulp and board mill, Stora Enso Skoghall, was carried out. A literature study was done and effluent wastewater from CTMP pulp production was analyzed. The analysis consisted of a broad constituent analysis and an anaerobic treatment trial. Results from these test where used to calculate the treatment effectiveness and resulting energy potential at the mill.The literature study and constituent analysis showed that toxicity of the water to be treated, due to wood extractives and sulphur content, was of concern. Detoxification chemicals targeting these constituents where used in the anaerobic treatment trial.

Sköldpaddsdammen som en naturlig oas på Mallorca : en fallstudie

This study shows how to plan a pond with an ecosystem which although it will have turtles living in it will not need to be cared. I will also demonstrate how this pond would be designed to work in the natural landscape on Mallorca. The background to the study is that I am interested to investigate how plants that we in Sweden are using as indoor plants are growing in their natural landscape and how to build a land-scape with them. The study highlights different cleaning-systems that can be used to clean a pond in a natural way. A comparison will be made between the conditions of an exterminated turtle-species which will live in this environment and a species that is easier to care for.

Anaerob rening vid StoraEnso Skoghalls Bruk

An analysis of a specific application of anaerobic wastewater treatment at a pulp and board mill, Stora Enso Skoghall, was carried out. A literature study was done and effluent wastewater from CTMP pulp production was analyzed. The analysis consisted of a broad constituent analysis and an anaerobic treatment trial. Results from these test where used to calculate the treatment effectiveness and resulting energy potential at the mill.The literature study and constituent analysis showed that toxicity of the water to be treated, due to wood extractives and sulphur content, was of concern. Detoxification chemicals targeting these constituents where used in the anaerobic treatment trial.

Fröåtjärns föroreningshistoria : Utredning av hur metallbelastningen varierat över tid med hjälp av sediment som ett naturligt historiearkiv

The metal mining history goes thousands of years back. The downside of the mining industry is the large amount of tailings created during the mining operations. Drainage and leaching of heavy metals from these tailings may cause major environmental problems including acid mine drainage and leaching of heavy metals. This study examines a pond located near an old mining site, where part of the old mining facility has been recently (1990) restored. The objective was to assess eventual metal contamination from historical mining and the recently performed restoration using a sediment core as a natural archive of historical metal inputs to the pond.

Växters förmåga att ackumulera metaller : Vass, bredkaveldun och gäddnate i Bergviks dagvattendamm

AbstractSurface-water includes different kinds of pollutants from traffic and roads. To prevent these pollutants to reach nearby lakes one can construct surface-water ponds on locations with heavy traffic. At Bergviks shopping centre in Karlstad, two ponds, one smaller and one bigger has been constructed in order to decrease the pollutant pressure from the receiving waters of Kattfjorden. Several heavy metals are essential for plants and animals in low concentration but when they occur in higher concentrations, they become toxic to the organism. The larger pond at Bergviks shopping centre has a sedimentation function so the heavy metals sink to the bottom thereby not releasing directly in to Kattfjorden.

Dagvattendammars reningseffekt : påverkande faktorer och metodik för statistisk modellering

Storm water is defined as runoff from precipitation such as rain or snow. It is collected in sewage disposal systems and since it mainly originates from urban areas it can contain high levels of heavy metals, nutrients and oil etc. Polluted storm water is currently treated by different methods such as wet ponds, constructed wetlands and filter strips. This study investigates these methods, which in earlier studies have shown to give varying results regarding their treatment efficiency.This thesis has been written on commission of SWECO VIAK and was aimed at studying those parameters that may affect the treatment efficiency of nutrients and heavy metals in storm water treatment facilities (STF:s). Through literature studies the dominating treatment processes in ponds and wetlands were examined.

Nursing technique and growth environment of Rabbit fish (Siganus guttatus) in the area of Tam Giang lagoon, Thua Thien Hue

SummaryIn the area to the east of Hue city, in Vietnam, lays Tam Giang lagoon, one of Asia's largest lagoons, with an area of 22,000 hectares. This lagoon is suitable for aquaculture. One reason for this is because the salinity differs from sweet to salty in different parts of the lagoon. The Vietnamese Government advocates an increase in environmentally-friendly aquaculture and the fish Siganus guttatus (Rabbit fish) is a candidate for this. This fish eats mainly algae and can be cultivated in a polyculture.

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.

Miljökonsekvenser av dagvattendamm i Skebäck, Örebro : en fallstudie hur miljöpåverkan av en dagvattendamm intill ett Natura 2000-område kan bedömas

Stormwater is surface runoff water that originates from precipitation or snowmelt and that on hardened surfaces prevents to infiltrate the ground. In city areas stormwater can consists of major amounts pollutants and when reaching a lake or watercourse it can cause damages on vegetation and animals. Therefore it is important to treat polluted stormwater before it reaches the recipient. The municipality of Örebro have since the 90ies an extensive work with treatment of stormwater in sedimentation ponds. A new stormwater treatment project is planned in an industrial estate in Skebäck, Örebro.

Modellstudie av föroreningsretention i Bäckaslövs våtmark : Tillämpning av modellverktygen MIKE SHE WET och MIKE 21

During the nineties, ecological handling of urban storm water became very popular in Sweden. Together with Chalmers University of Technology and two Swedish communities, DHI Water and Environment has been doing research of storm water ponds and constructed wetlands. This thesis work is a part of that research project. The work has been applied at the Bäckaslöv storm water treatment plant in Växjö, Sweden. The plant consists of one storm water pond and a downstream constructed wetland.

Utveckling av en äldre villaträdgård : från oplanerad till planerad

The result of this work is a plan for the development of an 1128 m2 elderly raised garden. The purpose has been to create an overall plan covering the long-term development of the garden. The work process has covered a description of the garden of today, review of requirements, analysis of the garden sections, design of a new plan as well as starting the construction of the new garden. The plan covers a time period of a couple of years to create the new garden since the construction work is carried out during spare time with small resources available. The planning must contain review of functions such as protection from insight, eating area and compost area. Also the esthetic expression must be planned. Colors, shapes, choice of material and plants together make up the esthetic expression. It is recommended to include anything you wish to create in the garden. In a raised garden one has to overcome the step to remove trees and shrubs and think different.

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