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21 Uppsatser om Aerated lagoon - Sida 1 av 2

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.

Kemisk karaktärisering samt nedbrytning av process- och avloppsvatten vid SCA Ortvikens pappersbruk

During pulp and papermaking process a huge amount of water is used. The wastewater contains a large amount of pollutants and has to be treated before it reaches the recipient. In March 2004 a new bleaching plant was started up at SCA Graphic Sundsvall AB, Ortviken?s paper mill using peroxide. The production of bleached thermo mechanical pulp and thus the load to the wastewater plant increased.

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.

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.

Rening av lakvatten vid deponin Degermyran i Skellefteå kommun : Utvärdering av nuvarande reningseffekt och simulering av mängden bildat lakvatten under 2000-talets klimatförändringar

At Degermyran landfill, situated in the municipal Skellefteå, a leachate treatment system was installed in 2005. One of the aims of this study was to investigate how well the treatment system works by using data from chemical measurements made on the leachate before and after treatment. Further this study had the purpose of investigating how the predicted climate changes of the 21st century will affect the amount of leachate generated at Degermyran by using a modified version of Thornthwaites water balance model. The treatment system has the ability of reducing manganese by 90 %, nitrogen by 73 % och TOC by 79 %. By the turn of this century the amount of precipitation that percolates the waste at Degermyran will be between 254 and 298 mm, depending on the amount of greenhouse gases that will be released in the future to come.

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.

Energieffektivisering av luftningssteget på Käppalaverket, Lidingö

This master thesis in energy optimization was made during the autumn of 2006 at Käppala wastewater treatment plant in Lidingö, Stockholm. A preceding thesis, where all electricity consumption was mapped, showed that the aeration in the biological treatment is the single largest consumer in the plant, and it is therefore of interest to reduce this cost. The oxygen control strategy used at Käppala WWTP is working well from a nutrient removal point of view, but not from an economic one. The last aerobic zones have a very low oxygen consumption during low loading periods which give rise to enhanced dissolved oxygen concentrations with excessive costs and reduced denitrification as a result. But also during periods of normal loading unnecessary high oxygen concentration are sometimes given.By modifying the aeration control strategy three full-scale experiments have been made, with the intention to reduce the air consumption.

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.

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.

Effect of vortex-processed water on tomato (Solanum lycopersicum) plants

This pilot study examined whether treatment with Vortex Process Technology (VPT) of the irrigation water used on tomato (Solanum lycopersicum) plants had any effect on plant growth. In a block experiment, with two blocks comprising 12 vases containing 1 L water and two tomato plantlets, treatment in which, nutrient solution was based on Vortex-treated water was compared with an control using untreated water. All vases were kept in a static aerated culture system in a daylight chamber for four weeks. The results showed that the effect of the two blocks exceeded the effect of vortex treatment in terms of leaf area and weight of fresh and dry matter. Plant height, stem width and internodal length were significantly different in tomato plants grown in Vortex-processed water compared with the untreated control.

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.

Kartläggning och nedbrytning av komplexbildare i ett integrerat kartongbruk

Skoghalls Bruk fick i juni 2005 tillstånd av miljödomstolen att öka kartongproduktionen från 665 000 till 800 000 ton kartong per år. Villkoren för tillståndet var att under en prövotidsperiod bl.a. utreda möjligheten att minska utsläpp till omkringliggande vatten.Syftet med examensarbetet var att kartlägga Skoghalls Bruks avloppssystem med avseende på komplexbildarna EDTA (etylendiamintetraättiksyra) och DTPA (dietylentriaminpentaättiksyra), kväve samt fosfor.Dessutom genomfördes nedbrytningsförsök i luftade dammar i laboratorieskala.För att få en klarare bild av nedbrytningen i Skoghalls Bruks luftade damm gjordes även en molekylviktsfraktionering på inkommande och utgående avloppsvatten.Komplexbildare används inom pappers- och massaindustrin för sin förmåga att binda till sig metalljoner som kan vara skadliga i processen. Metalljoner katalyserar nedbrytningen av väteperoxid i blekningen och påskyndar bildandet av aldehyder i kartongen vilket kan leda till lukt- och smakpåverkan.EDTA och DTPA anses vara stabila ämnen, vilket innebär att de är biologiskt svårnedbrytbara. Under den litteraturstudie som genomfördes fanns motsägande uppgifter angående nedbrytningen av komplexbildare, där vissa menade att de genomgår biologisk nedbrytning, men att det sker mycket långsamt.

Behandling av lakvatten med kemiska oxidationsmedel för att delvis bryta ned oönskade organiska förening : en studie utförd vid Hovgårdens avfallsanläggning i Uppsala

A renewed application for environmental permit for the Hovgården landfill in Uppsala shall be submitted before December 2004, therefore the municipality of Uppsala needs improved knowledge of the contents, mostly organic compounds in the leachate and they also want to find a method to minimize the emissions of these compounds. The purpose of this study was to find a practical and economical method based on chemical oxidation using oxidants. The oxidants investigated are Fenton's reagent, hydrogen peroxide, Oxypro, potassium permanganate and potassium persulfate. The study was made on untreated leachate and leachate that has been treated in an aerated dam followed by sedimentation dams collected from the Hovgården landfill, and alson on sludge water from sludge storage cells. The effects of the five oxidants have been established by analysing the UV absorbance at the wavelengths 253,7 nm and 260,0 nm at different pH values. The UV absorbance was used to indicate the amount of aromatic hydrocarbons in the water. Also analyses of iron and manganese were done after the experiments with potassium permanganate, hydrogen peroxide and Fenton's reagent.

Fuktvandring i putsade lättbetong- och tegelfasader : En undersökning om hur fukt vandrar och beter sig mot en putsfasad av två olika material med olika porositeter.

I dagsläget finns en stor mängd byggnader i Sverige där fasaden består av puts direkt anliggande mot antingen lättbetong eller tegel. Dessa fasader kan skapa problem för brukaren p.g.a. fukttransport via putsen direkt in i konstruktionen. Problemen som kan uppstå som följd av dessa konstruktioner är inte bara estetiska utan kan även påverka inomhusmiljön. Syftet med detta arbete var att undersöka om det gick att med ny teknik visa de resultat som framkommit från erfarenheter från praktiskt arbete samt undersöka hur en renovering påverkar de fasader som består av puts direkt mot lättbetong eller tegel.

Radon i betongkonstruktioner : - Kan det undvikas?

The following article consists of two parts; one part is about house construction and the other is a specialization about radon. The house construction part describes how to project a house from start. It contains the conformation of the house, the installations needed, calculations considering the strength of the construction, energy calculation and what materials were chosen. Calculations considering the costs of building and operate the house has been carried out. The result showed that the house would cost approximately two million Swedish kroner to build and thirteen thousand kronor a year to operate.

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