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Development of capacitive deionisation electrodes: optimization of fabrication methods and compositionSmith, Nafeesah January 2020 (has links)
>Magister Scientiae - MSc / Membrane Capacitive Deionisation (MCDI) is a technology used to desalinate water where a potential is applied to an electrode made of carbonaceous materials resulting in ion adsorption. Processes and materials for the production of electrodes to be applied in Membrane Capacitive Deionisation processes were investigated. The optimal electrode composition and synthesis approached was determined through analysis of the salt removal capacity and the rate at which the electrodes absorb and desorb ions. To determine the conductivity of these electrodes, the four point probe method was used. Contact angle measurements were performed to determine the hydrophilic nature of the electrodes. N2 adsorption was done in order to determine the surface area of carbonaceous materials as well as electrodes fabricated in this study. Scanning electron microscopy was utilised to investigate the morphology. Electrodes were produced with a range of research variables; (i) three different methods; slurry infiltration by calendaring, infiltration ink dropwise and spray-coating, (ii) electrodes with two different active material/binder ratios and a constant conductive additive ratio were produced in order to find the optimum, (iii) two different commercially available activated carbon materials were used in this study (YP50F and YP80F), (iv) two different commercially available electrode substrates were utilised (JNT45 and SGDL), (v) different slurry mixing times were investigated showing the importance of mixing, and (vi) samples were treated at three different temperatures to establish the optimal drying conditions.
Through optimization of the various parameters, the maximum adsorption capacity of the electrode was incrementally increased by 36 %, from 16 mg·g-1 at the start of the thesis to 25 mg·g-1 at the end of the study.
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Aufbereitung schwefelwasserstoffhaltiger Wässer durch katalytische Oxidation an porphyrinmodifizierten kohlenstoffhaltigen MaterialienDonner, Jan 28 January 2009 (has links)
In ariden Gebieten tritt Schwefelwasserstoff häufig im Grundwasser auf, wodurch dessen Nutzung für die Trinkwassergewinnung aufgrund des störenden Geruchs und Geschmacks stark beeinträchtigt wird. Die in der Praxis oft eingesetzte Belüftung erweist sich zumeist als ineffizient und führt zu Geruchsbelästigungen in der Umgebungsluft. Das Ziel der Arbeit, die im Rahmen eines deutsch-israelischen Forschungsprojekts angefertigt wurde, bestand darin, einen wirksamen und für den praktischen Einsatz bei der Wasseraufbereitung geeigneten Katalysator zur Entfernung von Schwefelwasserstoff zu entwickeln, hinsichtlich verschiedener Verfahrensparameter und relevanter Randbedingungen durch systematische Batch- und Säulenversuche zu erproben und zu optimieren. Wichtige Kriterien zur Charakterisierung der Katalysatoren waren die Kinetik des Sulfidumsatzes, die Langzeitstabilität und die Zusammensetzung der Reaktionsprodukte. Die Nachahmung natürlich vorkommender Strukturen (z. B. Häm-Gruppe) und deren Anpassung an eine katalytische Sulfidoxidation war der Grundgedanke am Anfang der Arbeit. Entsprechende Materialien, organische Metallkomplexe (Porphyrine) auf Kohlenstoffträgern (Acetylen Black), wurden bereits erfolgreich bei der Sauerstoffreduktion in Brennstoffzellen eingesetzt. Cobalttetraphenylporphyrin (CoTPP) zeigte von allen getesteten Materialien die beste katalytische Wirksamkeit zur Sulfidoxidation. Die Sulfidumsetzung lief sowohl bei höheren pH-Werten als auch mit zunehmender Temperatur schneller ab. Anhand von Untersuchungen zum Einfluss des pH-Werts konnte bestätigt werden, dass eine katalytische Wirksamkeit nur für die Oxidation der Sulfid-Spezies HS- und S2- besteht. Mit Aktivkohle konnte ebenfalls eine katalytische Sulfidumsetzung erzielt werden, jedoch lag die Aktivität hier im Vergleich zum CoTPP deutlich niedriger. Bei allen getesteten katalytisch wirksamen Materialien entstand als vorrangiges Reaktionsprodukt Schwefel, gebildete Schwefel-Sauerstoff-Verbindungen wie Sulfat und Thiosulfat waren von untergeordneter Bedeutung. Die Untersuchungen zeigten, dass Acetylen Black aufgrund der sehr geringen Teilchengröße technisch kaum einsetzbar ist, weshalb weitere Trägermaterialien erprobt wurden. Im Gegensatz zu Aktivkohle oder Anthrazit erwiesen sich Weichfilze, insbesondere der Sigratherm Kohlenstoff-Weichfilz (KFA-Filz), als sehr gut geeignete Trägermaterialien. Beim Einsatz von Aktivkohle lagerte sich der gebildete Schwefel in den Porenräumen ab, was zu einer erheblichen Verringerung der katalytischen Aktivität führte. Dagegen wurde unter Verwendung des modifizierten Filzmaterials auch bei sehr langen Laufzeiten (bis 3000 Stunden) keine Abnahme der katalytischen Wirksamkeit beobachtet. Durch diese Katalysatormatrix konnte somit die Deaktivierung des Katalysators durch elementaren Schwefel verhindert werden. Bei abschließenden Versuchen unter Verwendung einer kleintechnischen Versuchsanlage konnte gezeigt werden, dass der Katalysator für den großtechnischen Einsatz geeignet ist. Im Vergleich zur Aktivkohle sind zwar größere Investitionskosten notwendig, andererseits können mit dem CoTPP-Material deutlich längere Laufzeiten realisiert werden. Aufgrund seiner guten technischen Handhabbarkeit ist der modifizierte KFA-Filz sowohl in kleinen dezentralen Anlagen (ländliche Siedlungen) als auch in größeren Wasserwerken einsetzbar. Zusätzliche Chemikalien sind für den Betrieb eines solchen Filters nicht erforderlich. Eine weitere Verbesserung der Sulfidentfernung wird bei langen Filterlaufzeiten durch sulfidoxidierende Bakterien bewirkt. Das Ziel, einen effizienten, technisch einsetzbaren Katalysator zur oxidativen Sulfidentfernung aus Wässern zu entwickeln, wurde somit erreicht. / Hydrogen sulfide often occurs in groundwater of arid areas. Because of its malodour, H2S containing water cannot be used as drinking water without treatment. Aeration as the most common treatment technique is less effective and leads to nasty odour of ambient air. Catalytic oxidation could be an alternative. The aim of this work was to develop and to optimize a technically applicable oxidation catalyst as well as to test its applicability under practical conditions. Various N4-chelates (e. g. porphyrins), which are frequently used for the reduction of oxygen in fuel cells, were evaluated for catalytic oxidation of sulfide at selected boundary conditions and process parameters using batch and column experiments. The new catalysts should be characterized in comparison with other materials. The oxidation kinetics, the long-time stability of the catalyst and the composition of oxidation products were the main criteria used for catalyst assessment. Cobalt tetraphenylporphyrin (CoTPP) showed the highest catalytic activity of all tested materials. The rate of sulfide transformation increased significantly with increasing temperature and at pH values higher than 6. A catalyst suitable for technical use in fixed-bed reactors was obtained by coating of a supporting material (carbon felt KFA) with the active substance. For all investigated materials, sulfur was found to be the main reaction product of the sulfide oxidation. In contrast to activated carbon, which showed catalytic activity for sulfide oxidation too, modified KFA felt materials were not blocked and deactivated by formed sulfur, even after long-term use. The new catalyst is well qualified for a stable oxidation of sulfide in water. In comparison to activated carbon, higher investment costs are required, but the carbon felt supported porphyrin has a significant longer lifetime. Because of its easy use, modified KFA felt is applicable both in small local plants and in large waterworks. There is no necessity to add chemicals or to install complex control equipment. As a positive side-effect, further improvement of sulfide elimination caused by sulfide-oxidizing bacteria was found during long filter run times.
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Adsorpce pesticidů na granulovaném aktivním uhlí při úpravě vody / Adsorption of pesticides onto granular activated carbon in water treatment processKopecká, Ivana January 2010 (has links)
The diploma thesis is aimed at adsorption processes during the removal of pesticides onto granular activated carbon (GAC) in the process of drinking water treatment. Adsorption onto GAC represents an efficient method for pesticides removal. High adsorption efficiency can be significantly reduced due to the occurrence of natural organic matter (NOM) in raw water, which involves AOM (Algal Organic Matter) produced by phytoplankton. Analogous to NOM, AOM probably affects adsorption of pesticides by two different mechanisms - a direct site competition and pore blockage effect, in dependence on the different molecular weight of particular AOM fractions. Equilibrium batch and kinetic adsorption experiments were performed using two types of GAC (Norit 1240 and Filtrasorb 400) and two pesticides (terbuthylazine and alachlor). In order to examine the effect of AOM on adsorption of pesticides, raw GAC and GAC preloaded by AOM were used. The effect of pH on the competitive adsorption of AOM was also evaluated. A solid phase extraction (SPE) method and gas chromatography with electron capture detection (GC-ECD) were used to determine pesticides in water samples. AOM was characterized using fractionation onto sorptive resins. The representation of apparent molecular weights of AOM proteins was determined by...
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Biomass-Derived Activated Carbon Through Self-Activation ProcessXia, Changlei 05 1900 (has links)
Self-activation is a process that takes advantage of the gases emitted from the pyrolysis process of biomass to activate the converted carbon. The pyrolytic gases from the biomass contain CO2 and H2O, which can be used as activating agents. As two common methods, both of physical activation using CO2 and chemical activation using ZnCl2 introduce additional gas (CO2) or chemical (ZnCl2), in which the CO2 emission from the activation process or the zinc compound removal by acid from the follow-up process will cause environmental concerns. In comparison with these conventional activation processes, the self-activation process could avoid the cost of activating agents and is more environmentally friendly, since the exhaust gases (CO and H2) can be used as fuel or feedstock for the further synthesis in methanol production. In this research, many types of biomass were successfully converted into activated carbon through the self-activation process. An activation model was developed to describe the changes of specific surface area and pore volume during the activation. The relationships between the activating temperature, dwelling time, yield, specific surface area, and specific pore volume were detailed investigated. The highest specific surface area and pore volume of the biomass-derived activated carbon through the self-activation process were up to 2738 m2 g-1 and 2.209 cm3 g-1, respectively. Moreover, the applications of the activated carbons from the self-activation process have been studied, including lithium-ion battery (LIB) manufacturing, water cleaning, oil absorption, and electromagnetic interference (EMI) shielding.
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Activation of the carbonaceous material from the pyrolysis of waste tires for wastewater treatment.Malise, Lucky 07 1900 (has links)
M.Tech. (Department of Chemical Engineering, Faculty of Engineering and Technology), Vaal University of Technology. / The generation of waste tires is one of the most serious environmental problems in the modern world due to the increased use of auto mobiles all over the world. Currently there is a problem with the disposal of waste tires generated since there are strict regulations concerning their disposal through landfill sites. Therefore, there is a need to find ways of disposing these waste tires which pose serious health and environmental problem. The pyrolysis of the waste tires has been recognised as the most promising method to dispose the waste tires because it can reduce the weight of the waste tires to 10% of its original weight and produce products such as pyrolysis oil, pyrolysis char, and pyrolysis char. These products can be further processed to produce value added products. The char produced from the pyrolysis of waste tires can be further activated to produce activated carbon.
This study is based on the chemical activation of waste tire pyrolysis char to produce activated carbon for the removal of lead ions from aqueous solution. This was done by impregnating the waste tire pyrolysis char with Potassium hydroxide and activating it inside a tube furnace under inert conditions to produce waste tire activated carbon. Adsorbent characterisation techniques (SEM, FTIR, TGA, XRF, XRD, BET, and Proximate analysis) were performed on the waste tire pyrolysis char and the activated carbon produced to make a comparison between the two samples. The results showed that the waste tire activated carbon produced has better physical and chemical properties compared to the raw waste tire pyrolysis char.
Adsorption results revealed that waste tire activated carbon achieves higher removal percentages of lead ions from aqueous solution compared to waste tire pyrolysis char. The results also showed the effect of various process variables on the adsorption process. Adsorption isotherms, kinetics, and thermodynamics were also studied. The adsorption of lead ions agreed with the Freundlich isotherm model for both the waste tire pyrolysis char and waste tire activated carbon. In terms of adsorption kinetics, the experimental data provided best fits for the pseudo-first order kinetic model for both the waste tire pyrolysis char and the waste tire activated carbon. The adsorption thermodynamics study revealed that the process is an exothermic process and spontaneous in nature.
Response surface methodology was used to determine the combined effect of process variables on the adsorption of lead ions onto waste tire activated carbon and to optimise the process using numerical optimisation. The optimum conditions were found to be adsorbent dosage = 1g/100ml, pH = 7, contact time = 115.2 min, initial meta concentration = 100 mg/l, and temperature = 25°C to achieve a maximum adsorption capacity of 93.176 mg/l.
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Investigating the Impact of Permanganate Pre-Oxidation on Dissolved Organic Matter During Drinking Water Treatment Using Ultrahigh Resolution Mass SpectrometryLaszakovits, Juliana Rose 14 October 2021 (has links)
No description available.
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Utilization of exhausted coffee waste and date stones for removal of pesticides from aquatic media / Примeнa oтпaдa oд кaфe и кoштицa урмe зa уклaњaњe пeстицидa из aквaтичнoг мeдиjумa / Primena otpada od kafe i koštica urme za uklanjanje pesticida iz akvatičnog medijumaHgeig Ali 30 September 2020 (has links)
<p>The main goal of the thesis was to prevent the generation of waste, by<br />using the spent coffee grounds (SCG) and date stones (DSAC) for<br />production of activated carbon adsorbent for water treatment. The<br />substances for water removal were selected from those presenting<br />potential risk to aquatic environment according to the NORMAN list of<br />emerging substances and belong to the group of pesticides:<br />carbendazim, linuron and isoproturon. SCG and DSAC adsorbents, as<br />an eco-friendly and low-cost materials, showed high potential for the<br />removal of selected emerging pesticides.</p> / <p>Основни циљ тезе био је смaњeњe стварања отпада коришћењем oтпaдa oд кaфe (SCG) и кoштицa урмe (DSАC) за производњу активног угљa кao адсорбенса за пречишћавање воде. Изaбрaнe супстанце за испитивaњ прoцeсa уклањањa из воде представљају потенцијални ризик за воднe eкo систeмe према NОRМАN листи eмeргeнтних супстaнци и припадају групи пестицида: карбендазим, линурон и изопротурон. SCG и DSАC адсорбенти су, као еколошки прихватљиви материјали нискe цeнe, показали висок потенцијал уклањања одабраних пестицида из aквaтичнoг систeмa.</p> / <p>Osnovni cilj teze bio je smanjenje stvaranja otpada korišćenjem otpada od kafe (SCG) i koštica urme (DSAC) za proizvodnju aktivnog uglja kao adsorbensa za prečišćavanje vode. Izabrane supstance za ispitivanj procesa uklanjanja iz vode predstavljaju potencijalni rizik za vodne eko sisteme prema NORMAN listi emergentnih supstanci i pripadaju grupi pesticida: karbendazim, linuron i izoproturon. SCG i DSAC adsorbenti su, kao ekološki prihvatljivi materijali niske cene, pokazali visok potencijal uklanjanja odabranih pesticida iz akvatičnog sistema.</p>
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Removal of Microcystin-LR from Drinking Water Using Granular Activated CarbonVillars, Kathryn E., Villars 12 December 2018 (has links)
No description available.
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The Potential of Dissolved Air Flotation for PFAS Reduction in Norrvatten's Future Waterworks / Potentialen av Flotation för PFAS Reduktion i Norrvattens Framtida VattenverkVikström, Madeleine January 2023 (has links)
Norrvatten är en av Sveriges största dricksvattenproducenter. Med ett ökande behov av en större produktionskapacitet och nya regleringar, planerar dem att förbättra sin reningsprocess. En aspekt som kräver omfattande undersökning är val av reningsmetod för att nå den nya gränsen från Livsmedelsverket för fyra PFAS kemikalier. PFAS är en grupp kemikalier som är mänskligt producerade sedan 1950-talet, vilka är persistenta och farliga för människors hälsa. Deras stabilitet i miljön leder till att de ackumulerar i naturen och hamnar i mat och dricksvatten. För att uppnå de nya regleringarna måste Norrvatten minska sin PFAS4 koncentration från cirka 5.7 ng/L till 4 ng/L. PFAS-separationen är planerad att genomföras via antingen aktivt kol eller en kombination där flotation även implementeras. Aktivt kol har en bevisad möjlighet att separera och destruera PFAS4, men nyligen har indikationer på en potential hos flotation uppenbarats. Dock är forskningen kring dess effektivitet begränsad vilket medför ett behov av att utvärdera dess användbarhet. Denna rapport syftar till att förse Norrvatten med ett underlag på effektiviteten och gynnsamheten med flotation inför beslutet att implementera flotation. Av den anledningen undersöktes separationseffektiviteten som uppnås i en befintlig flotationsbassäng i Norrvattens vattenverk. Genom att mäta PFAS4 koncentrationen i inflödet, utflödet och slammet kunde en borttagningseffektivitet på 19-38% bestämmas för olika belastningar. Slamkoncentrationen mättes till ungefär 200-700 ng/L. Felkällor kunde identifieras i mätningarna eftersom massbalansen inte stämde överens trots att mätosäkerheten från analysen adderades. Dessutom gjordes en omanalys av två prover som skilde sig från det förväntade resultatet, vilket gav avsevärda skillnader i resultatet. Trots att några felkällor kunde identifieras kunde inte en fullständig förklaring till avvikelserna fastställas. Trots detta kunde slutsatser dras att den uppmätta separationseffektiviteten och slamkoncentrationen kunde förse ett korrekt intervall. Dessutom indikerade resultaten att flotation inte kan appliceras enskilt för att nå koncentrationsmålet utan bör kombineras med kompletterande kolfilter f ̈or att nå gränsvärdet. Flotation ger upphov till en mer koncentrerad ström av PFAS som kräver behandling för att eliminera kemikalierna från miljöns kretslopp. Flera potentiella behandlingsmetoder identifierades för hur slammet kan hanteras. Jämförelsen inkluderade aktivt kolfilter, jonbytare, membran, oxidationsprocesser, sonolys, förbränning, deponi, jordrening, flotation, skumfraktionering, behandling på reningsverk och återanvändning för jordförbättring. Metoderna jämfördes utifrån bevisad robusthet, kostnad och applicerbarhet. Ett möjligt slamhanteringsalternativ visade sig vara ett sekundärt steg med flotation, förbränning av det uppkoncentrerade slammet och behandling av permeatet med jonbytare. Med den föreslagna slamhanteringen kunde implementering av flotation utvärderas baserat på maximal PFAS destruktion, ekonomi, koldioxidutsläpp och energiförbrukning. Det visade sig att energiförbrukningen är större för processen som inkluderar flotation men koldioxidutsläppen är mindre. Dock är det möjligt att avgränsningarna för koldioxid kan ha gynnat flotationsprocessen eftersom utsläpp från reaktivering av kolfilter inkluderades men inte utsläpp från förbränning eller energiproduktion. PFAS destruktionen blev ungefär 1-2% större för processen med exklusivt kolfilter eftersom flotationsprocessen innehåller ytterligare en ström som släpper ut PFAS efter behandling med jonbytare. Det mest ekonomiska alternativet visade sig bero på koncentrationsgränsen där implementering av flotation var dyrare för en PFAS4 koncentration på 4 ng/L i dricksvattnet, men billigare vid en gräns på 3 ng/L. Slutligen upptäcktes det att volymen av sekundärt slam som beräknades att skickas till förbränning har en stor påverkan på driftkostnaderna. Därför bör optimeringar genomföras för att minimera den sekundära slamvolymen om flotation implementeras. / Norrvatten is one of the largest drinking water producers in Sweden. With the need to increase their production capacity and new regulations, they are planning to improve their treatment process. One aspect that requires extensive investigation, is the treatment approach to reach the new limit from the Swedish Food Agency of four PFAS chemicals. PFAS is a group of chemicals that have been humanely produced since the 1950s, which are persistent and hazardous to human health. Their environmental stability causes them to accumulate in nature and ends up in foods and drinking water. To fulfill the new regulations, Norrvatten has to decrease the PFAS4 concentration in their drinking water from approximately 5.7 ng/L to 4 ng/L. The removal is planned to be achieved through either activated carbon filters or a combination where dissolved air flotation is included. Activated carbon has a proven separation and destruction possibility for PFAS4 but recently, DAF has appeared to be a promising alternative. However, there is limited research on its efficiency, which establishes a need for investigations on the potential of DAF for PFAS removal. To navigate Norrvatten through the decision between exclusively applying GAC filters or implementing a combination with DAF, this thesis intends to provide a basis of its efficiency and favorability. Therefore, this thesis investigated the removal efficiency that was obtained in one existing DAF basin in Norrvattens waterworks. By measuring the PFAS4 concentration in the inlet, outlet, and sludge flow, a removal efficiency of 19-38% was acquired for different flow levels. In addition, the sludge concentration was measured to approximately 200-700 ng/L in the water phase. Presence of sources of errors could be identified in the measurements as the mass balance did not add up despite the addition of the measurement uncertainty in the analysis. Also, two samples were analyzed twice as the results differed from the expected results, which provided significant variations. Although some sources of error were identified, a full explanation for the differing results could not be disclosed. However, through some consistency, it was possible to conclude that the removal efficiency and sludge concentration could provide an accurate interval to illustrate the reality. In addition, the results indicate that DAF cannot be applied alone to reach the concentration goal, but has to be combined with additional GAC filters to reach the target. DAF provides a separation of PFAS into a sludge stream that requires treatment to remove the chemicals from the environmental cycle. To investigate how the sludge could be managed, several treatment methods were identified. The comparison included GAC, AIX, membranes, oxidation processes, sonolysis, incineration, landfill, soil cleaning, DAF, foam fractionation, treatment at a wastewater facility, and reuse for soil improvement. The methods were compared based on proven robustness, cost, and applicability. It was concluded that a viable alternative was to transfer the sludge to a second stage of DAF, incinerate the concentrated sludge, and treat the permeate with AIX. From the sludge management proposal, the implementation of DAF was analyzed based on maximum PFAS destruction, economics, carbon emissions, and energy requirements. It was found that the energy requirement was larger for the process including DAF but the carbon emissions are smaller. However, the delimitations on the carbon emissions may have been in favor of the DAF process as the GAC reactivation emissions are included but emissions due to incineration or energy production are excluded. The PFAS destruction was approximately 1-2% larger for the process that excluded DAF as an additional stream containing PFAS would be released into the environment after AIX, which is not present when only GAC is implemented. The economic out-come depended on the concentration limit, where implementation of DAF was more expensive for a treatment target of 4 ng/L in the drinking water and more economical for 3 ng/L. Lastly, it was found that the volume of the concentrated sludge that would be sent for incineration had a large impact on the operational cost. Therefore, if DAF is implemented optimizations are of relevance to minimize the volume of that stream.
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Removal of pharmaceutical residues from wastewater / Avlägsnande av läkemedelsrester från avloppsvattenGoralski, Alma January 2019 (has links)
Today, pharmaceutical residues are widely found in nature as a cause of the extensive use of human and veterinary medicine. The pharmaceutical residues have shown to have a damaging impact on flora and fauna. Wastewater Treatment Plants (WWTPs), today, are not designed for pharmaceutical removal, which calls for new methods and the implementation of these to avoid increased concentrations of pharmaceutical residues in nature. This thesis addresses three main areas. Firstly, a pre-study regarding the prevalence of pharmaceutical residues at different parts of a WWTP and in the nearby river, secondly, an evaluation of removal of pharmaceutical residues using ozone and, thirdly, the construction of a pilot plant scale Activated Carbon (AC) unit and an evaluation of its capacity for pharmaceutical and ozone removal. This work was done in order to verify the quality of a future full-scale unit including the advanced techniques ozone and AC that will be implemented at a WWTP for pharmaceutical removal. The pre-study shows that the total concentration of the Active Pharmaceutical Ingredients (APIs) was largest at the inlet (93.8 mg/L) and decreased throughout the process steps to be the lowest at the outlet (5.6 mg/L). Paracetamol was found in the highest concentration (86.5 mg/L) at the inlet but could not be detected in the outlet. In the recipient none of the APIs could be found. However, caffeine was detected in the recipient. The pilot plant studies were performed in a batch process, one at high ozone generation and one at low ozone generation. The pilot test at high ozone generation showed that all of the measured APIs were below their Limit of Quantification (LOQ) after 2 minutes. The pilot test at low ozone generation showed a total API-removal of 44% after 7 minutes, 78% after 13 minutes, 97% after 20 minutes and more than 99% after 60 minutes. All of the APIs were below their LOQ after 180 min. The AC-filter construction mirrored the conditions within a full-scale unit as closely as possible and was scaled by the superficial velocity. The AC-filter showed an ozone removal of approximately 99% and removed all pharmaceutical residues apart from Ranitidine which was decreased by 76%. / Idag återfinns läkemedelsrester i stor utsträckning i naturen, vilket är ett resultat av den omfattande användningen av human- och veterinärmediciner. Läkemedelsresterna har visat sig ha en skadlig effekt på flora och fauna. Dagens avloppsreningsverk är inte byggda för att rena vattnet från läkemedelsrester, vilket kräver att nya metoder utvecklas och implementeras för att förebygga spridning av läkemedel. Denna avhandling redogör för tre huvudområden, inledningsvis en förstudie om förekomsten av läkemedelsrester i olika delar av ett vattenreningsverk samt i en närliggande å. Därefter en studie av ozons förmåga att eliminera läkemedelsrester och slutligen konstruktion av ett aktivt kolfilter och en utvärdering av dess förmåga att ta bort läkemedel. Detta gjordes med syftet att verifiera kvalitén hos en fullskalig anläggning som kommer att installeras på ett vattenreningsverket där ozon och aktivt kol kommer användas för borttagning av läkemedelsrester. Förstudien visar att totalkoncentrationen av de aktiva läkemedelssubstanserna (API:er) var som störst vid inloppet av reningsverket (93.8 μg/L) och koncentrationen minskade genom de olika processtegen och var som lägst i utloppet (5.6 μg/L). Paracetamol återfanns i den högsta koncentrationen i inloppet (86.5 μg/L), men kunde inte detekteras i utloppet. Ingen av API:erna återfanns i recipienten, men däremot detekterades koffein. Pilotanläggningsstudierna genomfördes i en batch och genomfördes med högozongenerering och med låg ozongenerering. Studien med hög ozongenerering visade att alla läkemedelsrester var under analysmetodens detektionsgräns efter 2 minuter. Pilotstudien med låg ozonegenerering visade att den totala läkemedelsborttagningen var 44 % efter 7 minuter, 78 % efter 13 minuter, 97 % efter 20 minuter och mer än 99 % efter 60 minuter. Alla läkemedelsrester var under analysmetodens detektionsgräns efter 180 min. Kolfiltret konstruerades för att efterlikna det fullskaliga filtret så mycket som möjligt och skalades således efter den hypotetiska tomma bäddhastigheten. Kolfiltret tog bort cirka 99 % av ozonet och alla läkemedelsrester utom Ranitidin som reducerades med 76 %.
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