Sürdürülebilir Yeşil Kampüs Koleksiyonu / Sustainable Green Campus Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7755
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Master Thesis B and Se Transport Modeling in Saturated/Unsaturated Zones(Izmir Institute of Technology, 2002) Yüreklitürk, O. Emin; Tayfur, GökmenThere has been renewed interest in the application of models to the transport of non-point source pollutants. However, very little work has been done to evaluate the performance of a functional transient-state model for the transport of a reactive solute over an extensive study period. This research consists of mathematical modeling to simulate water flow, boron and selenium transport through soil in tile-drained croplands.For Boron part a mathematical model was developed to simulate non-conservative boron transport. The dynamic two-dimensional finite element model simulates water flow and boron transport in saturated-unsaturated soil system, including boron sorption and boron uptake by root-water extraction. Two different models have been employed for the sorption of boron. Similarly, for selenium part a finite element model is developed to simulate species of selenium transport in two dimensions in saturated/unsaturated zones. The model considers water, selenate, selenite and selenomethionine uptake by plants. It also considers oxidation/reduction, volatilization, and chemical and biological transformations of selenate, selenite, and selenomethionine. Comparison of boron transport model results with observed data is satisfactory. The model employed with Langmuir isotherm was found to give slightly better simulation results when compared with the model employed with Freundlich. The sensitivity analysis results indicate that the irrigation scheduling and the irrigation water quality are very important parameters for boron accumulation in the soil. Also the adsorption isotherm parameters, which reflect us the soil properties, are found to be important for the boron movement in the soil. Comparison of selenium transport model with observed data is not quite satisfactory in accuracy when compared with the model for boron transport. This may be the result of the complexity of the mechanisms affecting the selenium transport in soil. There are too many parameters, and due to the errors depending on the parameters, the total error for the estimation of the total selenium increases.Master Thesis Protection of the Marble Monument Surfaces by Using Biodegradaple Polymers(Izmir Institute of Technology, 2007) Ocak, Yılmaz; Sofuoğlu, AysunThe deterioration of historic buildings and monuments constructed by marble has been accelerated in the past century due to the effects of air pollution. The main pollutant Sulphur dioxide (SO2) reacts with marble composed primarily of calcite (CaCO3), the firs step of decay which called gypsum (CaSO4.2H2O) crust is formed and this process can be accelerated when the surfaces exposed to the rain.In this study, the possibilities of slowing down the SO2-marble reactions were investigated by coating the surface of marble with some bio-degradable polymers: zein, chitosan, polyhydroxybutyrate (PHB) and polylactic acid (PLA) as protective agents.Uncoated control marbles and biodegradable polymer coated marbles were exposed at nearly 8 ppm SO2 concentration at 100 % relative humidity conditions in a reaction chamber for several days. The extent of reaction was determined by leaching sulphate from the marble surface into deionized water and measuring the total concentration of sulphate with ion chromatography (IC). Then, gypsum crust thickness, polymers % protection factor and average deposition velocity were calculated. Concurrently, the ratio and amount of calcium sulfite hemihydrate (CaSO3.H2O)and gypsum (CaSO4.2H2O) were determined by FT-IR analysis. The surface morphology of SO2 exposed marble to distinguished calcium sulfite hemihydrate and gypsum crystals were determined by Scanning Electron Microscope (SEM).The results of the study showed that SO2-calcite reaction increased in the use of zein, glycerol added zein and chitosan polymers on the surface of marble. While, PHB treated marble surfaces had 5 % increases in the protection factor. The low molecular weight PLA protection factor was 45 % after 85 days exposure. Similar results were observed when the high molecular weight of PLA used. The protection was extended to more than 90 days having 60 % protection factor.Master Thesis A Chromatographicstudy of Carbon Monoxide Adsorption in Clinoptilolite(Izmir Institute of Technology, 2001) Narin, Güler; Ülkü, SemraAdsorption equilibrium and kinetic parameters for CO/clinoptilolite adsorbate/adsorbent pair were determined by perturbation gas chromatography. Chromatographic experiments were performed at temperatures in the 60-120°C range and at carrier gas flow rates in the range of 10.31-24.36 em/sec. The chromatographic response peaks were obtained by concentration pulse method. A packed column of 10 em length and 0.46 em inlet diameter which was packed with clinoptilolite particles with narrow size distribution (500-850 §) around mean diameter of301.9 § was used. The clinopti10lite particles were excavated from Gordes, Western Anatolia. The moments of the response peaks were calculated by integration of experimental chromatographic data and matched to the .model parameters in order to determine the equilibrium constants and diffusion coefficients. The dynamic model (Haynes and Sarma, 1973) was applied to describe the adsorption and diffusion processes in the packed column. This model includes axial dispersion, external mass transfer resistance, micropore and mesopore diffusion resistances. The equilibrium constants (Henry's law constants, K) were calculated in the range of 40 - 952 and were found to be in good agreement with the results in the literature. These constants were found to decrease with increasing temperature. The heats of adsorption were obtained in the range of 54.15 - 57.14 kl/mol from the slope of van't Hoff plots and compared with those in the literature. The heats of adsorption were found to be lower than those reported in the literature obtained for the same adsorbate/adsorbent pair. The higher heats of adsorption were explained by the smaller pore size, higher cation content of the clinoptilolite and more accessibility of the cations in the clinoptilolite framework by CO molecules. Heats of adsorption remained almost constant over the carrier gas velocity range studied. The contributions of axial dispersion and other mass transfer resistances Indiffusion of CO in clinoptilolite were also determined. The total dispersion exhibited slight change (average 0.035 see) with temperature implying that the micropore diffusional resistance was not dominant for diffusion of CO in clinoptilolite under the experimental conditions studied. The axial dispersion coefficient was determined in the range of 1.149.88 cm2/sec and the total mass transfer resistances were found between 0,02-0.06 sec. The results showed that the mesopore diffusion resistance was the controlling mechanism in CO diffusion in clinoptilolite. Mesopore diffusion coefficient was estimated as 2.98xlO-3 cm2/sec. This value was in good agreement with the theoretically determined value.Master Thesis Seasonal Variation in Disinfection By-Product Concentrations in Izmir Drinking Water(Izmir Institute of Technology, 2007) Baytak, Derya; Sofuoğlu, Sait CemilThe goal of this study was to investigate the seasonal variation in disinfection byproduct (DBP) concentrations in drinking water zmir. In accordance with this aim, drinking water samples were collected from tap water of five sampling points in the distribution system of three different water sources (Tahtalı Reservoir, Balçova Reservoir and ground water) during a 10 month period, from June 2006 to April 2007. The samples were analyzed by GC-ECD according to EPA Method 551.1. In addition, while the organic matter content (measured as NPOC) and bromide ion concentration were measured in samples from Tahtalı and Balçova Water Treatment Plants, other parameters including pH, temperature and chlorine dose were obtained from the treatment plants. These parameters were used as explanatory variables in the multivariate regression analysis to construct statistical models for DBPs. Trihalomethanes were the most abundant DBPs in all samples, followed by haloacetonitriles, chloropicrin and halogenated ketones. The mean total trihalomethanes (TTHMs) concentration of Balçova, Narlıdere and Güzelbahçe was 20.78 ppb while it was 94.71 ppb at Hatay. Concentrations of DBPs in all sampling locations were found to be the highest in spring and lowest in summer and fall. Although TTHM levels in all samples were found to be in accordance with the current drinking water regulations of Turkey, 41 % of the samples from Hatay exceeded the level that will be come into effect in 2012. Multivariate regression analysis suggested that water temperature and total chlorine dose were the most effective parameters for DBPs. In addition, simple regression analysis between total haloacetonitriles and TTHMs revealed a very high correlation (R2.0.83). Logistic regression models were able to predict the probability of exceedance of the selected TTHM thresholds with 76 % efficiency.Master Thesis Environmental Effects of Geothermal Applications Case Study: Balçova Geothermal Field(Izmir Institute of Technology, 2003) Çakın, Ayça; Gökçen Akkurt, GüldenDirect application of geothermal energy can involve a wide variety of end uses, such asspace heating and cooling, industrial applications, greenhouses, fish farming, and health spas. It uses mostly existing technology and straightforward engineering. The technology, reliability, economics and environmental acceptability of direct use applications of geothermal energy have been demonstrated throughout the world.The use of geothermal energy is the minimum waste forming type of energy in the world. Geothermal energy is also considered cheap, sustainable and environmentally friendly when compared to the other energy resources.Turkey has abundant geothermal resources because of its location. In particular, İzmir-Balçova district heating system is one example of the high temperature district heating applications in Turkey exhibiting high geothermal potential.The objective of the Thesis is threefold, namely: (a) to determine the negative and positive environmental effects of Balçova Geothermal District Heating System, (b) to find out sources of contamination if pollution exists (c) to offer a solution to protect the public health.Contamination may occur in Balçova Geothermal Field in either water phase or soil phase. Therefore, a sampling program was developed in order to monitor the alterations in water. The sampling points were chosen in a way that Balçova District Heating System production wells, groundwater wells, and the irrigation points could all be monitored.In order to investigate the contamination of the region, several parameters including physical properties such as temperature, electrical conductivity, total dissolved solids, alkalinity; non-metallic constituents such as ammonia, boron, chloride, silica, sulfate; and metals and semi metals such as calcium, magnesium, sodium, potassium etc. were determined.The results of this study showed that all of the samples had bicarbonate alkalinity. The concentrations of the parameters were not constant during the monitoring study. This may be because of the nature of geothermal fluid. During the studying period, concentrations of many heavy metals were below the limit of detection of atomic spectrometric techniques used in the study. Wells T and I did not seem to be suitable for drinking and irrigation water, respectively.In order to determine the effects of Balçova District Heating System on physical environment, noise measurements were conducted. The results of noise measurements have shown higher values than the acceptable limits of Noise Control Regulation.Master Thesis Removal of Heavy Metals From Wastewaters by Use of Natural Zeolites(Izmir Institute of Technology, 2001) Türkmen, Müşerref; Ülkü, SemraIn the present study, clinoptilolite rich local natural zeolite was proposed as an ion-exchanger for the removal of heavy metals (Pb2+, Cu2+, Zn2+) from wastewaters.Natural zeolite samples were exposed to a simple pretreatment process which included washing and drying to remove impurities and dust.Thermal and adsorption related properties of washed and original zeolite samples were determined by TGA and N2 adsorption analyses. In TGA analyses, average water content for washed and original samples were found as 9.44 and 10.13 % respectively. In N2 adsorption studies, both washed and original samples showed the characteristic Type IIb isotherm. BET surface areas of the samples were calculated as 39.73 and 47.72 m2/g for washed and original samples respectively.Pretreatment process was found to improve the adsorption capacity of clinoptilolite due to the removal of impurities and dust.In ion-exchange studies, efficiency of natural zeolite in removal of heavy metals from the solutions was investigated based on some physical and chemical variables. For this purpose, particle size and the amount of zeolite in the solution, contact time of the metal containing solution with zeolite were selected as physical variables and pH, metal concentration of the solution, and the presence of other ions were selected as chemical variables. The chemical analyses of all exchange solutions were performed by using ICP-AES. Removal % of the metal ions from the solutions were obtained. Based on the experimental results, zeolite exhibited a significant affinity to Pb2+, followed by Cu2+ and Zn2+ even in the presence of competing cations.To test the applicability of natural zeolite for the treatment of Acid Mine Drainage (AMD), zeolite samples were allowed to contact with simulated AMD solutions.Consequently, natural zeolite was found to be an efficient ion exchanger for removing lead, copper and zinc ions from aqueous solutions.Master Thesis Biosortion of Nickel (ii) by Using Waste Baker's Yeast(Izmir Institute of Technology, 2001) Özdemir, Peruze; Harsa, Hayriye Şebnem3 Biological methods for removing heavy metals are in competition with chemical and physical techniques such as precipitation, ion exchange, electrochemical treatment and evaporative recovery, especially, when the concentration of the heavy metal ion is low, between 1.0 and 100 mg/L. In order to qualify for industrial applications, biosorbents have to be produced at low cost. The use of biomass from various production stages; e.g. from the pharmaceutical or the food industries, is one way to minimize the costs. This study is concerned with the binding of nickel ions onto waste biomass of Saccharomyces cerevisiae genus, obtained from the food industry. Since the biomass employed is a waste material, biosorption process described in this study may represent a cheap alternative to conventional methods.Biomass cell walls, consisting mainly of polysaccharides, proteins and lipids, offer many functional groups which can bind metal ions such as carboxylate, hydroxyl, phosphate and amino groups.The objective of this study was to investigate the adsorption of nickel on wastebaker.s yeast as a function of several factors, i.e. pretreatment, pH, temperature, biomass concentrations and initial metal concentrations, in order to determine the optimum adsorption conditions of a batch process.Pretreatment of waste yeast biomass using sodium hydroxide, formaldehyde, nitric acid and ethanol decreased the sorption of nickel (II) ions compared with live biomass. Optimum initial pH for nickel (II) ions was 5.0 at the optimum temperature of 25o C. The uptake values increased with the increasing initial nickel (II) ion concentrations up to 150 mg/L. The optimum biomass concentration for this process was determined as 1.0 g/L.The biosorption isotherms were developed at various initial pH and temperature values. The equilibrium values were expressed with the Langmuir model while nickel sorption did not fit the Freundlich plot. The Langmuir parameters qmax (14.30 mg/L) and b (0.0069 L/mg) have been calculated."qmax" increased from 7.8 to 14.30 mg/L with the increase in pH from 3.0 to 5.0. Similar trend was observed for the "b" values; an increase from 0.0025 to 0.0069 L/mg were obtained when the pH of the solution was raised from 3.0 to 5.0. Both Langmuir model parameters were found to be the highest values at pH 5.0 which is consistent with the results of the optimization studies as described above.Temperature also affected the phase equilibria of nickel (II)/S.cerevisiae system.The highest capacity for biosorption system was obtained at 25o C with the qmax and b values of 14.3 mg/L and 0.0069 L/mg at pH 5.0, respectively. The enthalpy change for the biosorption process have been evaluated by using the Langmuir constant "b", which is related to the energy of adsorption. Nickel (II) biosorption is considered to be an exothermic process since low binding occurs when the temperature increases from 25 to 45o C.The uptake of nickel (II) ions by the yeast biomass was also investigated with respect to time under optimum operating conditions. Biosorption kinetics were rapid within the first few minutes. After the initial rapid uptake, further biosorption by yeast cells continued slowly and reached an equilibrium after 2 hours at all pH values of 3.0, 4.0 and 5.0. On the other hand, the rate of adsorption was found to be the fastest at pH 5.0 with an initial rate of around 3.59 mg Ni (II) / g-min.Master Thesis Effects of Biosurfactants on Remediation of Soils Contaminated With Pesticides(Izmir Institute of Technology, 2002) Zenginyürek, Özlem; Ertürk, HandanPesticides have played a significant role in increasing food production, and in view of growing worldwide food demand. Nevertheless; some of them have been classified as persistent toxic chemicals. This has resulted in serious concern about environmental contamination. Once a pesticide or toxic chemical find its way in the environment, a major part of it comes in contact with soil. There are several possible sources of pesticide contamination; at manufacturing, storage, or user sites. The most serious examples of pesticide contamination are typically the result of poor production and waste management practices of pesticide manufacturing, formulation, and application facilities. Improper storage, handling, and also have resulted in pesticide contamination at these sites and at landfills. Today, many remediation technologies are used to remove the pesticides from the soil. One of the soil treatment methods is enhanced biodegradation. Bioremediation of the soil has often proven to be a cheap solution for contaminated soil problem. This research was conducted to investigate the effectiveness of biologically produced surfactants (biosurfactants) on the biodegradation of pesticide-contaminated soil and evaluate the potential for biosurfactant-enhanced bioavailability of pesticide in soil. In order to determine the effectiveness of biosurfactants on pesticides, sophorolipid and rhamnolipid type biosurfactants were used. These biosurfactants were chosen since they are well characterized and their stimulating effect on the biodegradation of hydrophobic substrates was described in the literature. In this study, endosulfan and trifluralin were selected as pesticides. The study was performed in two stages in laboratory conditions. In the first part of the experiment, degradation of endosulfan-contaminated soil was studied by the presence of sophorolipid and in the second part of the experiment; rhamnolipid (JBR 425) was used on the removal of trifluralin-contaminated soil. Throughout the experiment, three different concentrations of sophorolipid and rhamnolipid were applied to soil which, are 0.98, 9.75 and 195 ppm for sophorolipid and 1.6, 100 and 1000 ppm for rhamnolipid. The effectiveness of synthetic or microbial surfactants on biodegradation of chemicals has been investigated by many researchers. However, studies about the biosurfactant enhanced soil remediation for the pesticide contaminants are limited. Besides that, the outcome of surfactant applications has been highly system-specific, conflicting results reported in the literature. Therefore, despite the general trends outlined in literature, the effect of biosurfactants on the biodegradation of organic compounds is poorly understood. Opposed effects are frequently observed. This study is the first M.Sc. thesis study about the use of biosurfactant enhanced bioremediation of pesticides in Turkey. The results from first part of our study obtained from sophorolipid, were not satisfactory since the degradation patterns for endosulfan were not affected by the presence of sophorolipid. According to the second experiment results, removal of trifluralin ranged from 24-35 %, with the increase in rhamnolipid concentrations. Addition of rhamnolipid (JBR 425) into the soil was found to increase the degradation rate of trifluralin by 13 % as compared to the control soil column. Additional time would probably increase the rate of degradation and bioavailability, as a result of providing the adaptation of microorganisms in contaminated soil media and formation of more bioavailable metabolites.Master Thesis Removal of Hydrocarbons From Wastewaters(Izmir Institute of Technology, 2002) Koltuksuz, Gülsan; Ülkü, SemraWastewater of chemical industries and petrochemical spills are the main sources of hydrocarbon pollution. Benzene, toluene and o- xylene are generally found in petrochemical spills which effect the all livings in the environment because of its toxicity.This thesis was an investigation of benzene, toluene and o- xylene (nonpolar aromatics) adsorption on clinoptilolite rich natural zeolite and surfactant modified zeolite. The aim of surfactant modification was to make highly polar zeolite surface hydrophobic and thereby remove the hydrophobic benzene, toluene and o- xylene molecules from the aqueous phase with the help of hydrophobic attraction forces.Cationic surfactants Dodecyl Amine (DA), Tetramethylammonium (TMA+) and an anionic surfactant Sodium Dodecyl Sulfate (SDS) were used for surface modification.The degree of surface hydrophobicity was examined by calculating the change in Gibbs free energy of the zeolite-water system by using the contact angle and surface tension measurement results in the presence and absence of surface modification. For natural zeolite the mean contact angle value was found 7.76o. Modification by DA and TMA+ increased .m from 7.76o to 51.13o and 29.37o respectively at a concentration of M. In case of SDS, at the pH value of 4, there was only a slight increase from 7.76 o to 18.03 o at a concentration of M. Effect of these surfactants on interfacial tension at air water interface was also different from eachother. DA decreased the surface tension from 72.8 to 37 dynes/cm while TMA+ did not bring any change. This part of the study showed that the presence of surfactant makes zeolite surface more hydrophobic.In adsorption studies, natural zeolite removed 20% of hydrocarbons from water. Except toluene, there was an optimum time that the removal was high. Presence of surfactant was able to increase this percent up to 40% under some conditions depending on the surfactant and hydrocarbon type and concentration. The highest benzene adsorption was obtained with TMA+ modified zeolite. The sequence was benzene > toluene > o-xylene. In case of DA modified zeolite, on the other hand, oxylene was adsorbed more than the other hydrocarbons. The removal follows the order o- xylene > toluene > benzene in this case.Master Thesis Anaerobic Co-Treatability of Olive Mill Wastewaters and Domestic Wastewater(Izmir Institute of Technology, 2003) Atayol, Ahmet Avni; Sofuoğlu, Aysun; Sofuoğlu, AysunHandling of olive mill wastewater (OMW) constitute an important problem for Mediterranean countries in general and western parts of Turkey in particular. This wastewater is seasonally produced and has high organic pollutant concentrations. Many treatment methods have been tried for its treatment, but a method having both sufficient treatment efficiency and economical feasibility could not be offered.Anaerobic treatment, having the advantages of applicability to high-strength and/or seasonal wastewaters, energy production and reduced costs, may be a good option. But olive mill wastewater is considered still to be highly polluted and not to have sufficient nutrients while domestic wastewater (DW) is assessed to be dilute and to have nutrients in excess for anaerobic treatment. Therefore anaerobic co-treatment of these wastewaters may be a better solution.In this study, the anaerobic co-treatability of OMW and DW was investigated by means of anaerobic treatability assays called Biochemical Methane Potential (BMP) tests. These tests were applied to OMW and DW mixtures of different ratios (OMW:DW of 1:9, 1:5, 1:3, 1:1, 1:0) at different organic loadings (4553 mg/l, 9107 mg/l, 13660 mg/l, 22767 mg/l and 34150 mg/l Chemical Oxygen Demand (COD) loading) with two different seed cultures. In order to determine the effect of nutrient addition, and the complementarity of these wastewaters, all tests were carried out both with (BM+) and without (BM-) the addition of a nutrient solution (basal medium).Results of the experiments showed treatment efficiencies around 80% at 4553 mg/l COD loading and around 70% at higher loadings for samples seeded with the culture obtained from the treatment plant of Efes Pilsen Brewery in İzmir, Turkey. For samples seeded with the culture obtained from the anaerobic digesters of Ankara Municipal Wastewater Treatment Plant, results were between 61% and 82% with the higher efficiencies at medium COD loading levels. A meaningful relation between DW content and treatment efficiency could not be observed; but the performance ratio of BMreactors to BM+ reactors increased with increasing DW content in the mixture, indicating the positive effect of DW addition. Reactors seeded with Efes culture did not require an acclimation period, while those seeded with Ankara culture did so. Efes seeded reactors, at all COD loadings, performed most of the gas production, around 75-80%, in about 15-20 days. Ankara seeded BM+ reactors required about 25 days for 80% production, while this period was about 35-45 days for BM- reactors.