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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Closing the Loop by Combining UASB Reactor and Reactive Bed Filetr Technology for wastewater Treatment : Modelling and Practical Approaches

Rodríguez-Gómez, Raúl January 2016 (has links)
A laboratory-scale upflow anaerobic sludge blanket (UASB) reactor followed by a packed bed reactor (PBR) filled with Sorbulite® in the lower part and Polonite® in the upper part was used to treat household wastewater in a 50-week experiment. A model was developed to describe the performance of the UASB reactor, including mass transfer through the film around anaerobic granules, intra-particle diffusion and bioconversion of the substrate. In a second model, a numerical expression describing the kinetics occurring in the granules was developed. It includes the resistances through which the substrate passes before biotransformation. These expressions were then linked to governing equations for the UASB reactor in order to describe degradation of the substrate, biomass growth (active and inactive), and variation in granule size over time. A third model was developed to describe the profile of the phosphorus (P) concentration throughout the PBR. In a first attempt, the analytical and numerical model was applied to data taken from previous studies in which UASB reactors were used to treat sugarcane mill wastewater and slaughterhouse wastewater. The results showed good agreement between observed and simulated results. Sensitivity analysis showed that diffusion coefficient and yield were important parameters in the UASB reactor model.The laboratory bench-scale experiment revealed that the combined UASB-PBR system efficiently treated the residential wastewater. Phosphorus, BOD7 and pathogenic bacteria all showed average removal of 99%, while total nitrogen showed a moderate reduction in the system (40%). Application of the numerical solution model to the experimental UASB reactor used resulted in good agreement between simulated and experimental values. Regarding the PBR, the model developed successfully predicted P removal. For both models, the capability and sensitivity analyses identified important parameters. A treatment system aiming to close the loop is suggested based on sequential UASB and PBR with biogas collection, nutrient recycling via sludge and filter media and elimination of pathogenic organisms. / <p>QC 20160226</p>
2

Engineered Wetlands and Reactive Bed Filters for Treatment of Landfill Leachate

Kietliñska, Agnieszka January 2004 (has links)
<p>The main objectives of this study were to investigate (i) anovel wetland treatment technology and (ii) selected bed filtermedia for the removal of contaminants from landfill leachate. Areview of the literature concerning experiences of the use ofconstructed wetlands (CW) for the removal of nitrogen fromlandfill leachate, showed that at least three groups oftreatment systems are in practice: sub-surface flow wetlands,hybrid systems (a combination of vertical and horizontal flowwetlands) and, compact constructed wetland (CCW). Most of thesetypeswere generally effective in reducing nitrogen (N,<i>e.g.</i>NH<sub>4</sub>-N, dominant N species in leachate) down toeffluent concentrations of about 10 mg L<sup>-1</sup>. Unfortunately, very little evidence ofresponsible mechanisms for the removal of N was presented,although some data indicated denitrification. The treatmentperformance of a compact constructed wetland (CCW) applied atthe Tveta Landfill, Södertälje, Sweden, wasevaluated. Chemically purified leachate and untreated leachatewere applied in periods of 7 day submergence and 7 day drainageto different sections of the CCW. The removal efficiency variedbetween 40 and 82%, and a mass removal rate of up to 5.1 g m<sup>2</sup>d<sup>-1</sup>was achieved. The chemical pre-treatment had adecisive role for the highest removal efficiencies obtained andit was unclear whether that treatment enhanced the efficiencybecause of lower toxicity and/or content of fewer competingcations. The possible combination of bed filter media and CCWas an ecotechnological treatment method for landfill leachatewas investigated by bench-scale laboratory column experiments.Reactive filter media (sorbents) was selected from their knownor suggested capacities for removal of heavy metals, nitrogenand phosphorus. Quartz sand or natural sand from an esker wasused as reference medium. Peat was used as an additionalcomponent in mixtures with the reactive media Polonite<sup>®</sup>(product from the bedrock opoka) and blastfurnace slag (BFS). A small column study also involved zeolite.Phosphorus was efficiently removed by Polonite<sup>®</sup>and NH<sub>4</sub>-N to some extent. Concerning metal removal, thebest performance was found as well for Polonite<sup>®</sup>, especially for Mn, Fe, Zn and Cu. The BFSshowed good removal efficiency for Cu, Ni and Mo. The removalof different elements was suggested to be a combination ofseveral factors,<i>e.g.</i>precipitation, ion exchange and adsorption. Priorto full-scale application of reactive filters at a landfillsite, matrix selection, filter design and operationalprocedures must be developed.</p><p><b>Keywords:</b>Blast furnace slag; Compact constructedwetland; Metals; Nitrogen; Polonite; Sorbents</p>
3

Engineered Wetlands and Reactive Bed Filters for Treatment of Landfill Leachate

Kietliñska, Agnieszka January 2004 (has links)
The main objectives of this study were to investigate (i) anovel wetland treatment technology and (ii) selected bed filtermedia for the removal of contaminants from landfill leachate. Areview of the literature concerning experiences of the use ofconstructed wetlands (CW) for the removal of nitrogen fromlandfill leachate, showed that at least three groups oftreatment systems are in practice: sub-surface flow wetlands,hybrid systems (a combination of vertical and horizontal flowwetlands) and, compact constructed wetland (CCW). Most of thesetypeswere generally effective in reducing nitrogen (N,e.g.NH4-N, dominant N species in leachate) down toeffluent concentrations of about 10 mg L-1. Unfortunately, very little evidence ofresponsible mechanisms for the removal of N was presented,although some data indicated denitrification. The treatmentperformance of a compact constructed wetland (CCW) applied atthe Tveta Landfill, Södertälje, Sweden, wasevaluated. Chemically purified leachate and untreated leachatewere applied in periods of 7 day submergence and 7 day drainageto different sections of the CCW. The removal efficiency variedbetween 40 and 82%, and a mass removal rate of up to 5.1 g m2d-1was achieved. The chemical pre-treatment had adecisive role for the highest removal efficiencies obtained andit was unclear whether that treatment enhanced the efficiencybecause of lower toxicity and/or content of fewer competingcations. The possible combination of bed filter media and CCWas an ecotechnological treatment method for landfill leachatewas investigated by bench-scale laboratory column experiments.Reactive filter media (sorbents) was selected from their knownor suggested capacities for removal of heavy metals, nitrogenand phosphorus. Quartz sand or natural sand from an esker wasused as reference medium. Peat was used as an additionalcomponent in mixtures with the reactive media Polonite®(product from the bedrock opoka) and blastfurnace slag (BFS). A small column study also involved zeolite.Phosphorus was efficiently removed by Polonite®and NH4-N to some extent. Concerning metal removal, thebest performance was found as well for Polonite®, especially for Mn, Fe, Zn and Cu. The BFSshowed good removal efficiency for Cu, Ni and Mo. The removalof different elements was suggested to be a combination ofseveral factors,e.g.precipitation, ion exchange and adsorption. Priorto full-scale application of reactive filters at a landfillsite, matrix selection, filter design and operationalprocedures must be developed. Keywords:Blast furnace slag; Compact constructedwetland; Metals; Nitrogen; Polonite; Sorbents
4

Avskiljning av koppar och zink från vägdagvatten med filtermaterialet Polonite : Experiment och modellering / Separation of copper and zinc from roadwater using the filter material Polonite : Experiment and modeling

Redin, Sigrid Hjelm, Lundholm, Sofia January 2021 (has links)
The number of hardened surfaces has increased as a result of urbanization, and thus also the amount of road stormwater. Road stormwater can transport pollutants that have been released on road areas to surrounding recipients. Two substances that are found in particularly high concentrations in road storm water are copper and zinc. At high concentrations of these substances, toxic effects occur which are particularly harmful to aquatic organisms. This report intends to investigate how well the filter material Polonite purifies road stormwater from copper and zinc. Polonite is a reactive filter material made of the sedimentary rock Opoka, which binds substances such as copper and zinc by adsorption. In this thesis, a laboratory experiment has been carried out where it has been investigated how well different amounts of Polonite adsorb copper and zinc during different time periods. The results show that the concentrations of copper and zinc generally decreased over time and with an increasing amount of Polonite. Furthermore, a simulation of how Polonite's purification capacity decreases over time has been created. The simulation showed that Polonite's ability to purify stormwater according to the guideline values ceases after 133 days for copper and 325 days for zinc. Data collected from a column experiment was then compared with the simulation. The comparison showed that the simulation for zinc was in good agreement with the data from the column experiment, while the data for copper were more different from the simulation.  Conclusions drawn are that Polonite can be a good solution for sustainable road stormwater management as it can purify zinc and copper in accordance with the recommended guideline values. The results also show that Polonite has a better ability to purify zinc than copper and that it can purify zinc for a longer period of time. Moreover, other aspects such as economics need to be investigated in future studies to establish with certainty that Polonite is a good solution for the purification of road stormwater in large-scale treatment plants. / Till följd av urbaniseringen ökar antalet hårdgjorda ytor, och därmed även mängden vägdagvatten. Vägdagvatten kan transportera föroreningar som uppkommit på vägområden till omgivande recipienter. Två ämnen som hittas i särskilt höga koncentrationer i vägdagvatten är koppar och zink.  Vid höga koncentrationer av dessa ämnen uppstår toxiska effekter som är särskilt skadliga för vattenlevande organismer. Denna rapport ämnar att undersöka hur väl filtermaterialet Polonite renar vägdagvatten från koppar och zink. Polonite är ett reaktivt filtermaterial som genom adsorption kan rena vägdagvatten. I detta arbete har en laboration utförts där det har undersökts hur väl olika mängder Polonite adsorberar koppar och zink under olika tidsperioder. Resultatet visar att halterna koppar och zink generellt minskar med tiden samt med ökande mängd Polonite. Vidare skapades en simulering av hur Polonites reningsförmåga minskar med tiden.  Slutsatser som dragits är att Polonite kan vara en god lösning för hållbar vägdagvattenhantering då det kan rena koppar och zink i enlighet med de rekommenderade riktvärdena. Resultatet visar även att Polonite har en bättre förmåga att rena zink än koppar samt att det kan rena zink under en längre tidsperiod. För att med säkerhet fastställa att Polonite är en bra lösning för rening av vägdagvatten i storskaliga reningsanläggningar behöver flera aspekter såsom ekonomi undersökas i framtida studier.
5

”Rätt avlopp på rätt plats” : – Livscykelanalys av tre enskildaavloppsanläggningar / "Right sewage system in the right place" : - Life cycle assessment of three on-site wastewater treatment options

Sörelius Kiessling, Helene January 2013 (has links)
”Rätt avlopp på rätt plats” – Livscykelanalys av tre enskilda avloppsanläggningar Problemen med övergödning i Östersjön och i Sveriges insjöar är stort och enskildaavlopp pekas ut som en central aktör, framförallt beträffande fosforutsläppen. I Sverigefinns det ungefär en miljon enskilda avloppssystem och nästan hälften av dessa har enså pass bristande vattenrening att de inte uppfyller gällande lagstiftning. Utvecklingenav nya tekniker för rening av avloppsvatten har länge strävat efter att minska utsläppenav övergödande ämnen, detta ibland på bekostnad av andra utsläpp, så somväxthusgaser och försurande ämnen.Det här examensarbetet har därför med hjälp av metodik från livscykelanalys (LCA)utvärderat tre enskilda avloppssystem med tanke på deras utsläpp av växthusgaser,försurande gaser samt övergödande ämnen. Då misstanke också fanns att de lokalaplatsegenskaperna påverkar de enskilda avloppssystemens totala miljöpåverkan,utfördes även en intervjustudie med ett antal av landets kommuner. I intervjustudiengjordes ett försök att identifiera de platsegenskaper som påverkar valet ochutformningen av de enskilda avloppssystemen. De tre avloppssystemen som ingick istudien är markbädd samt kompaktfilter i kombination med antingen ett reaktivt filtermed Polonite®, eller i kombination med kemfällning.Resultatet av studien visade att markbädden hade lägst utsläpp av både växthusgaseroch försurande gaser, men högst utsläpp av övergödande ämnen. De tvåfosforreducerande systemen uppvisade betydlig bättre potential för att reduceraövergödande ämnen, men detta på bekostnad av större utsläpp av växthusgaser ochförsurande gaser, speciellt i fallet med det reaktiva filtersystemet. Lokalaplatsegenskaper, så som näringsretention, visade sig spela en central roll för deundersökta avloppssystemens totala miljöpåverkan. I områden med hög fosforretentionunder vattnets väg till havet skulle avloppssystem med höga utsläpp av fosfor (så somdet markbaserade systemet) kunna vara försvarbara. På de platser i landet därövergödningen är problematisk finns det dock motiv för att använda fosforreducerandesystem. / "Right sewage system in the right place" - Life cycle assessment of three on-sitewastewater treatment options The problem with eutrophication in the Baltic Sea and in Swedish lakes is serious andon-site wastewater treatment systems are considered important, especially forphosphorus emissions. There exist about one million on-site wastewater treatmentsystems in Sweden and almost half of them do not meet current legislation.Development of new technologies for on-site wastewater treatment systems has for along time been focused on reducing emissions of eutrophying substances. However,there is a risk that this reduction could be achieved at the expense of other emissions,such as greenhouse gases and acidifying substances.This master thesis has therefore by use of life cycle assessment (LCA) evaluated threeon-site wastewater treatment systems considering their total emission of greenhousegases, acidifying gases and eutrophying substances. Because local site characteristicswere thought to affect the sewage systems overall environmental impact, an interviewstudy were also carried out with a number of municipal officials. The interview studywas designed to identify the local site characteristics that influence the selection anddesign of the on-site wastewater treatment systems. The three sewage systems includedin the study were a soil treatment system with surface water discharge and a compactbiological filter in combination with either a reactive filter module with Polonite®, or incombination with chemical precipitation.The results of the study reveal that the soil treatment system had the lowest emissions ofboth greenhouse gases and acidifying gases, but the largest emissions of eutrophyingsubstances. The two phosphorus reducing systems showed significantly greaterpotential to reduce the emissions of eutrophying substances, but at the expense of largeremissions of greenhouse gases and acidifying gases, especially in the case of thereactive filter system. Local site characteristics such as the retention of nutrients, provedto play a vital role in the investigated sewage systems overall environmental impact. Inareas with high retention of phosphorus sewage systems with high emissions ofphosphorus (such as the soil treatment system) where favored. However, in areas whereeutrophication is problematic, it is justified to use phosphorus reducing systems.
6

Dephosphorisation of Acidic Wastewater : Aimed to allow the recirculation of byproducts as slag builders

Welander, Henrik, Palm, Martin January 2018 (has links)
This study was conducted to evaluate if Polonite® could remove Phosphorus from Sandvik’s wastewater that naturally forms during steelmaking, and hence be proficiently used as a precursor of the neutralization process of said steel plant. Currently lime (CaO) is mixed with the wastewater which creates clean water and sediments, that later need to be landfilled. Due to the high Phosphorus content in the sediments these cannot be recycled back into the production, this result in a loss of important elements. The aim is therefore to remove the Phosphorus to a target level of 1-2 [mg/L]. In fact, the Phosphorus present in the wastewater drifts in the solid particles derived by the neutralization process, impairing their possible recirculation as slag builders. To evaluate the purifying abilities of Polonite® a batch test and a column test were conducted. During the column test measurements of pH and conductivity were made. To analyze the composition, Inductively Coupled Plasma (ICP) tests were performed. No clear correlation between the pH and the conductivity of the water could be established from the results. Overall the Polonite® removed high amount of Phosphorus from the wastewater. The target level of 1-2 [mg/L] Phosphorus was achieved in the batch test. Although, Polonite® also incidentally absorbed most of the Fluorine present in the wastewater making it a questionable choice for the process, as Fluorine is desirable in large quantities in the sediments if used as slag builders. As no ICP results were received from the column test only pH and conductivity are discussed. / Denna studie utfördes för att utvärdera om Polonite® kunde rena Fosfor från Sandvik’s avfallsvatten som naturligt uppkommer från stålprocesserna, och använda det som ett försteg i neutraliseringsprocessen. Idag blandas kalk (CaO) med avfallsvattnet vilket resulterar i rent vatten och sediment, dessa deponeras sedan. På grund av den höga halten Fosfor i sedimenten kan dessa inte återcirkuleras in i produktionen, detta leder till att viktiga ämnen går förlorade. Målet är därför att sänka halten Fosfor till en nivå på 1-2 [mg/L]. Fosfor i avfallsvattnet driver i de fasta partiklarna från neutraliseringsprocessen, vilket förhindrar möjligheterna att återanvända dem som slaggbildare. För att utvärdera Polonites® reningsförmåga gjordes ett kolumntest och ett skaktest. Under kolumntestet mättes pH och konduktivitet. För att analysera innehållet i vattnet gjordes ICP-tester på det renade vattnet. Inget tydligt samband mellan konduktiviteten och pH kunde fastställas från resultaten. Överlag hade Polonite® en hög grad av rening av Fosfor. Den givna mängden av Fosfor uppnåddes i skaktestet. Olyckligtvis hade Polonite® även en hög reningsgrad av Fluor som även fanns i avfallsvattnet, vilket gjorde Polonite® tvivelaktigt försteg i denna process, då Fluorrikt vatten är önskat för att kunna användas som slaggbildare. Då inga ICP-resultat har mottagits diskuteras enbart pH och konduktivitet för kolumntesterna.
7

Fosforavskiljning i reaktiva filter vid småskalig avloppsrening / Reactive Filter Materials for Removal of Phosphorus in Small Scale Wastewater Treatment Plants

Stark, Therese January 2004 (has links)
<p>An excessive input of nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone. In the column experiment, the phosphorus sorption capacity in BF-slag and BF-slag mixed with burned limestone was observed under saturated and unsaturated flow conditions for 10 weeks. The waste water used in both experiments originated from the full scale testing site at Ångersjön in Sweden. After the column experiment was ended, the filter materials were investigated with XRD (X-ray diffraction) and SEM (scanning electron microscope) in order to figure out which chemical reactions that had taken place.</p><p>The results from the batch experiments show that fine Polonite® and BF-slag mixed with limestone have the fastest P sorption capacity. Already after 5 seconds of shaking the materials showed effective retention of P. The coarse Polonite®, Filtralite® and BF-slag showed similar sorption capacities, although the coarse Polonite® tended to be somewhat inferior. The column studies showed that the materials used in the columns had a sorption capacity of 98 % or more. The XRD and SEM indicated that an amorphous calcium-P-compound was created in the filter material.</p> / <p>I Sverige är reningen av fosfor i vatten från enskilda avlopp ofta bristfällig, vilket bland annat kan leda till övergödning av sjöar, hav och vattendrag. Sedan några år tillbaka har olika filtermaterial med speciella reaktiva egenskaper, som bland annat avskiljer fosfor från avloppsvatten, undersökts. Tanken med filtermaterialen är att de efter mättnad med näringsämnen ska kunnas användas som jordförbättringsmedel. I denna rapport har några olika filtermaterial, lämpade för fosforavskiljning, undersökts genom skak- och kolonnförsök. I skakförsök, där skaktiderna varierade mellan 5 sekunder och 60 minuter, testades Polonite®, Filtralite®, Hyttsand och Hyttsand blandad med 10 % bränd kalk. Polonite® är en upphettad form av bergarten opoka varav två olika kornstorleksfraktioner (0-2 mm och 1-4 mm) användes. Filtralite® och Hyttsand är antropogena filtermaterial. Filtralite® tillverkas i Norge och består av kalkhaltiga kulor av expanderad lera (Leca®). Hyttsand framställs genom vattenkylning av masugnsslagg som bildas vid framställningen av råjärn vid stålverket i Oxelösund. I kolonnförsöken, som utfördes under 10 veckor, studerades Hyttsand och Hyttsand blandad med 10 % bränd kalk under omättade och mättade flödesförhållanden. I samtliga experiment användes avloppsvatten från reningsverket vid Ångersjön, där Filtralite® och Hyttsand testas i fullskala. Efter kolonnförsöken avslutats undersöktes filtermaterialen med XRD (röntgendiffraktion) och SEM (svepelektron mikroskop) för att utreda vilka mekanismer som medverkat vid avskiljningen av fosfor.</p><p>Resultaten från skakförsöken visade att finkornig Polonite® och Hyttsand blandad med kalk avskiljer fosfor effektivt redan efter skakning i 5 sekunder. Grovkornig Polonite, ren Hyttsand och Filtralite® sorberade fosfor tämligen likartat, även om den grovkorniga Poloniten® tenderade att vara aningen sämre än de övriga. Resultaten från kolonnförsöken visade att fosfor kunde avskiljas till över 98 % i alla kolonner och att det bildats amorfa fosfatföreningar, främst med kalcium, under den 2,5 månader långa experimentperioden.</p>
8

Fosforavskiljning i reaktiva filter vid småskalig avloppsrening / Reactive Filter Materials for Removal of Phosphorus in Small Scale Wastewater Treatment Plants

Stark, Therese January 2004 (has links)
An excessive input of nutrients to lakes and other water bodies has created a problem with eutrophication in Sweden. Untreated, or partially treated, domestic sewage is a major source for discharge of phosphorus (P), which is the nutrient most frequently responsible for eutrophication of most fresh waters and the Baltic Sea. The waste water can be cleaned by filter materials, which have a high P-retention ability and which after saturation may be used as fertilizers. Four potentially suitable filter materials were tested in batch- and column experiments in this study. In the batch experiments, the following materials were shaken with waste water in time series ranging from 5 seconds to 60 minutes: coarse (1-4 mm) and fine (0-2 mm) Polonite® (heated bedrock from Poland); Filtralite® (light expanded clay aggregates with limestone added before burning); water cooled blast furnace slag (BF-slag) and BF-slag mixed with 10% burned limestone. In the column experiment, the phosphorus sorption capacity in BF-slag and BF-slag mixed with burned limestone was observed under saturated and unsaturated flow conditions for 10 weeks. The waste water used in both experiments originated from the full scale testing site at Ångersjön in Sweden. After the column experiment was ended, the filter materials were investigated with XRD (X-ray diffraction) and SEM (scanning electron microscope) in order to figure out which chemical reactions that had taken place. The results from the batch experiments show that fine Polonite® and BF-slag mixed with limestone have the fastest P sorption capacity. Already after 5 seconds of shaking the materials showed effective retention of P. The coarse Polonite®, Filtralite® and BF-slag showed similar sorption capacities, although the coarse Polonite® tended to be somewhat inferior. The column studies showed that the materials used in the columns had a sorption capacity of 98 % or more. The XRD and SEM indicated that an amorphous calcium-P-compound was created in the filter material. / I Sverige är reningen av fosfor i vatten från enskilda avlopp ofta bristfällig, vilket bland annat kan leda till övergödning av sjöar, hav och vattendrag. Sedan några år tillbaka har olika filtermaterial med speciella reaktiva egenskaper, som bland annat avskiljer fosfor från avloppsvatten, undersökts. Tanken med filtermaterialen är att de efter mättnad med näringsämnen ska kunnas användas som jordförbättringsmedel. I denna rapport har några olika filtermaterial, lämpade för fosforavskiljning, undersökts genom skak- och kolonnförsök. I skakförsök, där skaktiderna varierade mellan 5 sekunder och 60 minuter, testades Polonite®, Filtralite®, Hyttsand och Hyttsand blandad med 10 % bränd kalk. Polonite® är en upphettad form av bergarten opoka varav två olika kornstorleksfraktioner (0-2 mm och 1-4 mm) användes. Filtralite® och Hyttsand är antropogena filtermaterial. Filtralite® tillverkas i Norge och består av kalkhaltiga kulor av expanderad lera (Leca®). Hyttsand framställs genom vattenkylning av masugnsslagg som bildas vid framställningen av råjärn vid stålverket i Oxelösund. I kolonnförsöken, som utfördes under 10 veckor, studerades Hyttsand och Hyttsand blandad med 10 % bränd kalk under omättade och mättade flödesförhållanden. I samtliga experiment användes avloppsvatten från reningsverket vid Ångersjön, där Filtralite® och Hyttsand testas i fullskala. Efter kolonnförsöken avslutats undersöktes filtermaterialen med XRD (röntgendiffraktion) och SEM (svepelektron mikroskop) för att utreda vilka mekanismer som medverkat vid avskiljningen av fosfor. Resultaten från skakförsöken visade att finkornig Polonite® och Hyttsand blandad med kalk avskiljer fosfor effektivt redan efter skakning i 5 sekunder. Grovkornig Polonite, ren Hyttsand och Filtralite® sorberade fosfor tämligen likartat, även om den grovkorniga Poloniten® tenderade att vara aningen sämre än de övriga. Resultaten från kolonnförsöken visade att fosfor kunde avskiljas till över 98 % i alla kolonner och att det bildats amorfa fosfatföreningar, främst med kalcium, under den 2,5 månader långa experimentperioden.
9

Phosphorus recycling from wastewater to agriculture using reactive filter media

Cucarella Cabañas, Victor January 2007 (has links)
<p>This thesis focused on testing the suitability of reactive filter media used for phosphorus (P) removal from wastewater as fertilizers, thus recycling P to agriculture. The work compared the P sorption capacity of several materials in order to assess their suitability as a source of P for plants. The selected materials (Filtra P, Polonite and wollastonite) were saturated with P and used as soil amendments in a pot experiment. The amendments tended to improve the yield of barley and ryegrass compared with no P addition. The amendments also increased soil pH, P availability and cation exchange capacity in the studied soils. The substrates studied here can be of particular interest for acid soils. Of the materials studied, Polonite appears to be the most suitable substrate for the recycling of P from wastewater to agriculture</p>
10

Phosphorus Removal from Domestic Wastewater Using Dual Reactive Materials Polonite® and Absol®.

Fatehi Pouladi, Soheil January 2011 (has links)
Private wastewater treatment facilities release tons of phosphorus to the aquatic environment due to the insufficient removal efficiency in conventional soil infiltration systems. Reactive filter materials have demonstrated promising P removal rates. Laboratory-scale column experiments were carried out using Absol® and Polonite® in dual infiltration media and results were compared with Polonite® functioning as the only layer of reactive filter material. Two sets of experiments were arranged with layer lengths of 5 cm and 15 cm which were operated for 50 and 119 days respectively. Columns with an additional layer of Absol® demonstrated very good average removal rates of 85.99 % and 99.13 % in both experiments while the effluent in the former exceeded the maximum allowed P concentration shortly after half of the total time of the experiment. On the other hand, O-P concentration in collected samples from dual filter media with 15 cm layers of Absol® and Polonite® (column B1) was as low as 0.04 mg/l after 119 days of operation exhibiting high potentials for Absol® in local wastewater treatment. Levels of pH in treated samples showed a decreasing trend in all columns which was similarly simultaneous with high removal rates observed in B1.

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