Följande arbete kommer att lyfta fram olika alternativ för rening av mänsklighetens viktigaste förutsättning för liv, nämligen för vatten. Syftet är att undersöka olika alternativ för vattenrening och skapa en manual på hur bra dessa är lämpade till plats och förhållande. Arbetets mål är att undersöka vilka olika metoder för vattenrening som finns idag, utvärdera dessa utifrån indikatorer för hållbarhet med hänsyn till sociala, ekonomiska och miljömässiga aspekter, ta fram kostnadsberäkningar för de olika metoder samt ta fram alternativ till vattenrening som redan används och därför kommer rapporten ta reda på vilka dessa är och var de finns, samt hur väl dessa fungerar på respektive plats och under vilka förhållande. / This examination task will highlight different options for water purification, which is humanity's most important condition for life. The purpose is to investigate different alternatives for water purification and create a manual on how well these are suitable for location and association. The aim of the work is to investigate what different methods of water purification are available today, evaluate sustainability indicators based on social, economic and environmental assessments, to prepare cost estimates for the different methods and provide alternatives for water treatment which are already in use and therefore the report will determine which those are and where they exist, and how well they work in each place and under what conditions.

Hydrogen sulfide is commonly found in many Florida potable groundwater supplies. Removing sulfur species, particularly hydrogen sulfide is important because if left untreated, sulfide can impact finished water quality, corrosivity, create undesirable taste and odor, and oxidize to form visible turbidity and color. This document presents the results of a study designed to investigate the removal efficiencies of a variety of tray aerators in Central Florida in order to develop a predictive mathematical model that could be used to determine tray effectiveness for sulfide removal. A literature review was performed that indicated there was limited information regarding the removal of hydrogen sulfide using conventional tray aerators, and no information regarding the removal of total sulfide from tray aerators. There was significantly more information available in the literature regarding the usefulness of sulfide removal technologies from water supplies. Consequently, the lack of literature regarding sulfide removal using tray aerators suggested that there was a need for additional research focused on sulfide removal from water flowing thru tray aerators. Several water purveyors that relied on tray aerators as a part of their water treatment operations were contacted and requested to participate in the study; three water purveyors agreed to allow the University of Central Florida (UCF) to enter their secured sites to collect samples and conduct this study. The three facilities included the UCF‘s water treatment plant located in Orlando and situated in eastern Orange County, the City of Lake Hamilton‘s water treatment plant located in west-central Polk County, and the Sarasota-Verna water treatment plant located in western Sarasota County. An experimental plan was developed and field sampling protocols were implemented to evaluate sulfide removal in commonly used tray aerators at the three drinking water treatment facilities. Total iv sulfide concentrations passing through the trays were determined in the field at each site using a standard iodometric analytical technique. In addition, other water quality parameters collected included dissolved oxygen, pH, temperature, conductivity, turbidity, alkalinity, hardness, total dissolved solids and total suspended solids; these samples were collected and analyzed either in the field or at the UCF laboratory. A first-order empirical model was developed that predicted sulfide removal in tray aerators. The model‘s constant was evaluated with respect to the water‘s proton concentration [H + ], the tray aerator‘s surface area, and hydraulic flow rate thru the trays. The selected model took the form of Cn=C0 (10-kn ) where Cn is the sulfide remaining after aeration in mg/L, C0 is the sulfide entering the distribution tray in mg/L, n is the number of tray stages in the aerator, and . From the empirical model, it was shown that sulfide removal was negatively impacted as the proton concentration (H+ ) decreased, and flow increased. Conversely, it was observed that increased sulfide removal occurred as the available tray aerator surface area increased. The combined parameters of proton concentration, flow rate, and area were statistically evaluated and used to develop an empirical constant that could be used in a first order model to predict sulfide removal in tray aerators. Using a site-specific derived experimental (empirical) constant, a water purveyor could use the developed model from this work to accurately predict sulfide removal in a tray aerator by simply measuring the total sulfide content in any raw groundwater supply and then providing the desired number of tray stages available for treatment.

Yes / This paper presents a study to assess the roof-harvested rainwater (RHRW) in the Ikorodu area of Lagos state, Nigeria, and recommends guidance to minimise the health risk for its households. The types, design and use of rainwater harvesting systems have been evaluated in the study area to inspect the human risk of exposure to Escherichia coli (E. coli). To achieve these objectives, a detailed survey involving 125 households has been conducted which showed that 25% of them drink RHRW. Quantitative microbial risk assessment (QMRA) analysis has been used to quantify the risk of exposure to harmful E. coli from RHRW utilised as potable water, based on the ingestion of 2 L of rainwater per day per capita. Results have revealed that the maximum E. coli exposure risk from the consumption of RHRW, without application of any household water treatment technique (HHTTs) and with application of alum only, were 100 and 96 respectively, for the estimated number of infection risk per 10,000 exposed households per year. This estimation has been done based on 7% of E. coli as viable and harmful. Conclusively, it is necessary that a form of disinfectant be applied to the RHRW before use.

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I Sverige har ungefär 1,2 miljoner människor enskild dricksvattenförsörjning och en stor andel av dessa har problem med vattenkvalitet. En utvärdering av reningstekniker har inletts av företaget Ecoloop och Utvecklingscentrum för vatten och detta examensarbete fördjupar och följer upp de inledande resultaten från det projektet. Med hjälp av en litteraturstudie, modellering i Visual MINTEQ och fem fallstudier utvärderades reningsteknikerna jonbytarfilter och nanofilter avsett för enskild dricksvattenförsörjning med avseende på reduktion av föroreningarna bly och uran. Fallstudierna visar att jonbytarfilter kan fungera väl för att reducera uranhalter men en viss inkörningsperiod förekommer där bieffekter, exempelvis kemisk smak, kan förekomma samt att underhåll är viktigt för att fortsätta ha en hög reduktionsgrad. Fallstudierna kunde ej besvara ifall nanofilter är en lämplig reningsteknik för ändamålet att reducera halter av bly och uran under de gränsvärden som finns, eftersom de membranfilter som använts i fallstudierna visade sig ha för stor porstorlek för att kallas nanofilter. En slutsats är att det är viktigt att fortsätta med provtagning av vattnet även efter att ett filter installerats. Utöver det genomfördes intervjuer och en enkätundersökning som undersökte hur kommuner i Sverige arbetar för att möta enskilda brunnsägare i deras utmaningar med vattenkvalitet. Intervjuerna och enkätsvaren visar på en variation där några kommuner jobbar aktivt för att stötta de enskilda brunnsägarna med rådgivning, bidrag och förebyggande åtgärder medan andra kommuner är mer passiva och låter de enskilda ta eget ansvar för sitt vatten. / About 1.2 million people in Sweden rely on their own private drinking water supply for their daily needs and a large portion of those have problems with water quality. An evaluation of water treatment technology intended for private wells has been initiated by the companies Ecoloop and Utvecklingscentrum för vatten and this master’s thesis further develops and follows up the initial results. By conducting a literature review, doing modelling in Visual MINTEQ and carrying out five case studies the two water treatment techniques nanofilter and ion exchange are evaluated in the context of domestic water supplies with water quality problems caused by either lead or uranium. The case studies shows that ion exchange filters can reduce uranium in drinking water below the threshold value but with some initial side effects (i.e., chemical taste of the water). The case studies could not show if nanofilters are suitable to reduce lead or uranium from domestic water supplies, since the pore size was found to be too big for the membrane filters used in the case studies to be called nanofilters. This concludes that it is important to proceed with sampling of the water even after installing a filter for water treatment. Additionally, interviews and a survey were conducted which investigated how municipalities in Sweden are working to meet private well owners in their challenges with water quality. The answers from the interviews and the survey displays a variation where some municipalities are actively supporting the private well owners through counselling, grants, and preventive measures while other municipalities are more passive and leaves the individual well owners responsible to look after their water quality by themselves.

Both Part I and Part II are included. / The separation of a mixture of glass spheres in water using 2 inch hydrocyclones was studied. <p> Three operating parameters were investigated: feed concentration, volume split and feed flow rate. In addition, three design parameters were cone angle, inlet diameter, and vortex finder length. The performance criterion parameters were the efficiency with which the solids were separated from the liquid, and the energy required per unit mass flowing through the hydrocyclone. </p> <p> First the experimental data were analyzed by three different statistical methods and the results compared in an attempt to determine which statistical method was most suitable for this two criteria system. The three methods were principal component analysis, canonical correlation analysis and multiple regression analysis. The theory behind these methods is briefly outlined. Our conclusion is that using all three methods give much more insight than could be obtained from any individual method. </p> <p> Second, an analysis of the above eight hydrocyclonc parameters of hydrocyclones with cylindrical sections indicated that for the range of parameters covered in this work, feed flow rate and inlet diameter influenced the energy loss most; volume split influenced the separation efficiency the most. Energy loss and separation efficiency are quite independent; this means that it is possible to design and run a hydrocyclone with high separation efficiency and low energy loss. The dilute concentrations used in this work indicate that a hydrocyclone of conventional design can be used in waste water treatment. When the parameters were correlated, a power model gave more consistent interpretation than a linear model. </p> <p> Third, the effect of the three operating parameters on hydrocyclones with three different body shapes suggested that the most efficient cyclone was one with a straight cone and no cylindrical section. The body shape dictated which parameters would significantly affect performance. </p> / Thesis / Master of Engineering (ME)

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Ph. D. (Department of Chemistry, Faculty of Applied and Computer Sciences), Vaal University of Technology. / The study based on thiourea derivatives has received significant interest from several disciplines due to their variable bonding modes, promising biological implications and their complexation capacity. Thiosemicarbazones are a stimulating type of ligands that reveals a diverse range of biological activities. They are effectual intermediates for the production of pharmaceutical and bioactive materials which makes them very useful in the field of medicinal chemistry. The FTIR spectral variations in the stretching frequencies of C=N, C–N and C=S that appeared at 1663, 1327 and 726 cm-1, respectively confirmed the formation of the ligand. The present study describes the preparation of (Z)-2-(pyrrolidin-2-ylidene)thiourea ligand for the synthesis of ZnS, CdS and Ag2S nanoparticles via homogeneous/chemical precipitation technique. The effect of different capping agents such as starch, PVP, PEG, PVA, and the role of ammonium hydroxide solution during the synthetic processes was investigated and distinguished. The study based on the effect of capping molecule on the formation of nanoparticles proved that the capping agent has a great influence on the formation of nanoparticles. The FTIR spectra of the capped nanoparticles revealed the shift toward the higher frequencies compared with the uncapped metal sulfide nanoparticles. The metal sulfide nanoparticles also showed an increased in energy band gaps which were different from the bulk materials. The 2-hydroxy-1-naphthaldehyde is regarded as a low-cost ligand which has also been widely used in biological synthesis to determine free amino acid groups. The metal complexes of this ligand are easily prepared and can be used to synthesize metal oxide nanomaterials at low cost which are environmentally friendly that can be expended in bio-applications. The preparation of the Zn, Cd and Ag complexes based on the bis(2- hydroxy-1-naphthaldehydate ligand through the reaction desired metal acetate are reported and confirmed by FTIR spectroscopy, elemental analysis and thermogravimetric analysis (TGA). There has been a great research significance for the synthesis of metal oxide since such materials have high specific surface area and a high fraction of surface atoms. The synthesis of ZnO, CdO and Ag2O nanoparticles through thermal decomposition of the Zn(II), Cd(II) and Ag(I) complexes into trioctylphosphene oxide (TOPO) and/or hexadecylamine (HDA) at different decomposition temperatures is reported. The study proved that the combination of oleylamine as a solvent and TOPO as a capping molecule produced controlled shaped and reasonably dispersed particles. The XRD patterns of all the metal oxide nanoparticles synthesized with TOPO were showing face-centred cubic structures. These metal oxide based complexes were also used as single source precursors to prepare metal oxide thin films at different annealing temperatures on the glass substrate using different methods such as annealing, thermal decomposition, aerosol assisted chemical vapour deposition (AACVD) methods. The optical absorption and size distribution of the synthesized nanoparticles and thin films have been explored using XRD, SEM, AFM, FTIR, PL and UV-Vis spectroscopy techniques. The results show that the decomposition temperature has a huge effect on the formation of the nanomaterials. The SEM images of the as synthesized nanoparticles revealed different shapes of the particles as the decomposition temperature is increased. A change in X-ray diffraction parttern was observed when the decomposition temperatures were increased. The capped metal sulphides and metal oxide nanoparticles were then allowed to react with polydadmac or chitosan to form the polymer nanocomposites. The optical absorption, luminescence properties, size distribution and the bonds distribution of the polymer nanocomposites were characterized with UV-Vis, PL and FTIR spectroscopy. The structural and morphological properties have been studied by XRD, TEM and SEM. The absorption analysis of the prepared nanocomposites revealed the properties of both nanoparticles and polymers. Chitosan and polydadmac are biopolymers that have been proven as the best adsorbents to remove the heavy metal ions from wastewater.In this study, polydadmac and chitosan based metal sulphide and metal oxide nanocopmposites were used as adsorbents for the removal of Fe(III) from the wastewater. The batch experiments were conducted to achieve the optimum conditions. The effect of pH, contact time, and initial metal ion concentration were also determined. The pH = 8 was found to be the optimum pH for the removal of Fe(II) ions from the water sample by utilizing pure chitosan and chitosan nanocomposites as adsorbents.

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