The aim of this study was to evaluate the effects on a simulated wastewater plant regarding GHG emissions and use of energy and resources when implementing source separated wastewater systems. The effects were studied for different restrictions of effluent quality and for different temperatures on the influent. The simulation model BSM2G calibrated for Käppala wastewater treatment plant was used. The task was executed by simulating nine different scenarios with an increase in influent load from new connections equivalent to 3, 10 and 30 % of the present connections. These new connections were served by conventional, urine separated or black water separated systems.

Perfluorinated substances (PF) are environmental pollutants that are used to coat fibres of so called ?all weather clothes? to make them water resistant. PF are effectively spread through water. Waste water treatment plants (WWTPs) are a pollutant source of these substances. PF are poisonous to different kinds of organisms, and supposedly also to human beings, if concentrations are sufficiently high.Perfluorinated substances have been investigated at three waste water treatment plants in Stockholm during the 2000?s.

Society has depended on fossil-based fuel for a long time, which has led to a fundamental increase of greenhouse gases in the Earth?s atmosphere. To tackle this problem the international community has agreed that action is necessary. Focus is now directed towards local extraction of energy from renewable sources such as biogas.Utö is participating in the Green Island project, which aims to investigate the possibility of making the island climate neutral. This report has been implemented on behalf of Skärgårdsstiftelsen, the main partner responsible for the Green Island project in Sweden.

Hammarby Sjöstad is a new district of southern Stockholm built with focus on reduced environmental impact by recirculation of materials and sustainability. The environmental goals aim to cut the water consumption by half and a separate storm water treatment. Thus, the wastewater will be more concentrated and will originate from the households only. The Sjöstad project includes the idea of a local treatment plant for the household wastewater. To evaluate this possibility, Sjöstadsverket, an experimental treatment plant was constructed.

The requirements for wastewater treatment plants (WWTP) are gradually increasing, partly because of higher incoming loads, which in turn require a more efficient treatment process. In parallel with environmental and economic goals there are also desires to lower energy consumption without compromising the wastewater treatment. Furthermore, there is a demand on WWTP´s to alter eutrophication in aquatic systems through better nitrogen and phosphorus removal. An increasing number of WWTP´s have acquired biological nitrogen and phos-phorus removal. A by-product of this type of biological treatment is the formation of nitrous oxide, which is a potent greenhouse gas.

Sewage sludge contains plant nutrients and has earlier been utilised as fertilizer to cropland. Unfortunately not only plant nutrients but also heavy metals, pathogens and organic contaminants tend to accumulate in sludge. The suitability to use sewage sludge in agriculture has therefore been subject to several discussions over the years. The Swedish food industry does no longer accept sludge as fertiliser for Swedish producers. In 1999 the Swedish parliament accepted several objectives for environmental protection. In order to prevent environmental pollution and further exploitation of the earth crust, one of these objectives confirm that phosphorous from sewage shall be recirculated to arable land.

Chemical substances are spread diffusely and uncontrollably as a result of the increased consumption of goods. REVAQ is a certification system that works to reduce the flow of hazardous substances to Swedish treatment plants and to create a sustainable nutrient recycling. According to REVAQ, the yearly accumulating rate of metals should not exceed 0.2% in soil per year. Silver and bismuth are two metals that do not fulfill this requirement. The silver concentration in sludge decreased during the last decade, however the last few years, it has leveled off.

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 goal of this master thesis project was to develop computer models of some plausiblepretreatment techniques and to assess the potential benefits/costs of using pretreatment andanaerobic digestion for waste management of organic waste from a system perspective. Forthis purpose a computer program called ORWARE has been used. ORWARE (organic wasteresearch) is a program for making life cycle assessments of waste management. As the mainpart of the project work the ORWARE system has been provided with three new models ofpretreatment techniques. The additions consist of: One model of pretreatment with ultrasound,one model of thermal hydrolysis and one model of a screw press.

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.

Chemical substances are spread diffusely and uncontrollably as a result of the increased consumption of goods. REVAQ is a certification system that works to reduce the flow of hazardous substances to Swedish treatment plants and to create a sustainable nutrient recycling. According to REVAQ, the yearly accumulating rate of metals should not exceed 0.2% in soil per year. Silver and bismuth are two metals that do not fulfill this requirement. The silver concentration in sludge decreased during the last decade, however the last few years, it has leveled off.

The most common way to treat wastewater in Sweden today is by a combination of an Activated sludge process and a chemical treatment. These processes are not very energy efficient and may not be the most environmentally friendly. That is why it is interesting to evaluate new alternative methods to see if they can be less harmful to the environment and help to a lower resource consumption. New techniques are tested in a pilot installation at Hammarby Sjöstad, Sjöstadsverket. To be able to evaluate these techniques in a wide perspective system analyses are conducted where different impacts can be considered, advantages and disadvantages in the systems.Five system structures for water treatment have been constructed in Matlab/Simulink in this study.

AbstractThe dependency of fossil fuels in the transport sector causes large emissions of carbondioxide. This problem can we reduce by using vehicle gas from digested solid manure and leftover of pasture. I have studied the potential for this in the county of Västernorrland. Thepurpose is to investigate how much vehicle gas that can be extracted.One central, large scale digestion and upgrade plant should be placed in Härnösand. Theamount of pasture and manure that is economical and practical available is enough to produce2,7-3,5 millions Nm3 vehicle gas.

Bringing back the nutrients from the city to the country is becoming increasingly important, as the world?s stores of nutrients get more exhausted. Sewage sludge is an unapplied resource, rich in plant nutrients, which could replace parts of the commercial fertilizers used in Sweden today. Sewage sludge may contain large amounts of pathogens, such as Campylobacter and Salmonella, why use can cause severe spreading of infections, both to animals and humans. These pathogens have the ability to survive for a long time in soil and water and therefore some sort of treatment of the sludge is recommended before use.

Avloppsreningsverk står inför uppgiften att rena inkommande vatten för att möta lagstiftade gränsvärden till en så låg kostnad som möjligt. Att syresätta biologiska reningsprocesser är kostsamt eftersom luftningsanordningen förbrukar mycket energi. Ungefär en femtedel av Himmerfjärdsverkets totala elenergiförbrukning går till luftning av biologiska processer.För att öka Himmerfjärdsverkets energieffektivitet startades under 2010 experiment med olika strategier för luftflödesstyrning. En av verkets nitrifikationsbassänger byggdes då om för att möjliggöra zonvis reglering av syrehalten.Syftet med denna studie var att utvärdera reglering med ammoniumåterkoppling och syrehaltsprofil för styrning av Himmerfjärdsverkets nitrifikationsprocess. Utvärderingen baserades på reningsresultat och energiförbrukning.Med nuvarande reglerstrategi varieras luftningen genom återkoppling från syrehalten i den andra av sex zoner i varje luftad bassäng.