In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with Aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

In the production of pulp, paper and cardboard, a large amount of water is used daily. The water has to be purified in the internal purifying plant before it reaches the receiving body of water. In the biological purifying stage at the Stora Enso Skoghall mill, an aerated basin is used where the microorganisms, using oxygen, oxidize the organic material to carbon dioxide. The air is pumped from the bottom of the basin and the oxygen can then be transported from the air bubbles to the water through diffusion. The problem with Aeration of waste water from the forest industry is that wood residues, such as fatty acids, are making the transport of oxygen in water more difficult.

Pulp- and papermills expend vast amounts of water in order to produce pulp, paper and cardboard. Hence, they alsocreate vast amounts of waste water which has to be cleaned before it can be released into the receiving body of water. Insuch a wastewater treatment plant, tremendous amounts of energy are expended by the Aeration in the biologicalcleaning process. This Aeration is necessary to supply the microorganisms that shall decompose organic material withoxygen, which they need for their metabolism. The transfer of oxygen from the gas phase to the liquid phase isprimarily inhibited by surface-active substances in the waste water like resin acids or fatty acids.

This thesis has been done at the powder department (GH) at AB Sandvik Coromant in Gimo. With a rheometer measurements has been made on raw materials and powder blends. The focus of this report has been to find correlations between raw material powders and press data, comparisons have also been made between raw materials and powder blends.The rheometer can show information of how a powder act in flow conditions, together with air and with pressure. Analyses has been done comparing the rheometer data with press parameters (for example: rejected orders, weight variations and the compaction pressure) with the goal to find correlations between the powders flow properties and the powders compaction in production.The measurements and analyses have been showing that the powder flow properties depends on the powders composition and that properties like flow rate, Aeration and permeability varies between powder blends and batches of the same powder sort. It seems to exist a correlation between the pressure force and the flow rate of a raw material.

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.

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.

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.

Detta examensarbete utreder möjligheterna att utveckla en energieffektiv luftningsstrategi i en aktivslamprocess. Arbetet innehåller först en litteraturstudie där forskningsläget gås igenom.Därefter följer en optimeringsstudie i Matlab, en simuleringsstudie i en förenklad variant av Benchmark Simulation Model No 1 (BSM1) och en redogörelse för ett fullskaleförsök vid Käppalaverket.  Resultaten från optimeringsstudien visar att, under vissa förutsättningar, är ett konstant luftflöde energioptimalt. Simuleringsstudierna visar att en minskning av energiförbrukningen på upp till 16%  kan uppnås, då luftflödet hålls konstant, jämfört med att hålla ett konstant ammoniumbörvärde. Preliminära resultat från fullskaleförsöken indikerar att ett konstant luftflöde kan minska luftförbrukningen men en längre utvärdering bör genomföras för att få mer tillförlitliga resultat.Slutsatsen från detta arbete är att den utvecklade metodiken kan vara intressanta alternativ till en överordnad reglering av ammoniumkoncentrationen och bör därför studeras vidare..

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.

This thesis has been done at the powder department (GH) at AB Sandvik Coromant in Gimo. With a rheometer measurements has been made on raw materials and powder blends. The focus of this report has been to find correlations between raw material powders and press data, comparisons have also been made between raw materials and powder blends.The rheometer can show information of how a powder act in flow conditions, together with air and with pressure. Analyses has been done comparing the rheometer data with press parameters (for example: rejected orders, weight variations and the compaction pressure) with the goal to find correlations between the powders flow properties and the powders compaction in production.The measurements and analyses have been showing that the powder flow properties depends on the powders composition and that properties like flow rate, Aeration and permeability varies between powder blends and batches of the same powder sort. It seems to exist a correlation between the pressure force and the flow rate of a raw material.

This master thesis has been done in cooperation with Sweco Viak AB in Sundsvall. The aimwith the project is to investigate the purifying effect of percolation filter due to iron andmanganese. The overall goal was to investigate how the parameters surface load,sandfractions, and burden time affect the purifying effect. The expectation is to optimize thedesign and find a demouldning of the filter that gives sufficient purifying with a highersurface load. As an attempt to accelerate the curing of the filter, experiments with a layer ofsand which surface has been covered with manganese ore (MnO2) on top of the filter havebeen done.As test filters 10 L bars were used and the experimental work was performed at thewaterworks in Hassela and Munkbysjön.In Hassela different sandfractions were tested.

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.

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.

På Käppalaverket i Stockholm står luftningen av de biologiska bassängerna för omkring en femtedel av verkets totala elenergiförbrukning. I ett försök att minska energikostnaden utvärderades under hösten 2010 nya metoder för luftflödesreglering på verket. Grundtanken var att styra luftflödet efter medelvärdet på utgående ammoniumkoncentration under en längre tid, istället för som idag efter momentana värden.Ett vanligt sätt att styra luftflöden på reningsverk idag är att använda återkoppling från utgående ammoniumkoncentration, vilket syftar till att alltid hålla den utgående koncentrationen vid ett valt börvärde. Lagstiftade gränsvärden på ammonium avser dock normalt medelvärden över en längre tid, såsom kvartal eller år. Istället för att anpassa luftflödet efter den inkommande belastningen är det därför möjligt att hålla luftflödet relativt konstant medan istället den utgående koncentrationen tillåts variera.I denna studie visades en energibesparing kunna erhållas om luftflödets variation reduceras.

Because of the increasing trends in energy consumption and increased environmental awareness, greater focus has been placed on improvement and development of renewable energy sources. An already proven and accepted method is biogas production from anaerobic digestion at municipal wastewater treatment plants.In the waste water treatment process solid material and dissolved pollutants are separated from the water, forming a sludge. The sludge is separated from the process and stabilized during anaerobic digestion or aerobic Aeration. Most often, mesophilic anaerobic digestion is used. Because of degradation by microorganisms, biogas with a high content of methane is formed during the digestion.