Çevre Bilimleri

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Wastewater treatment by land disposal on sandy grounds
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1984., 1984.) Baysal, Ayşegül.; Curi, Kriton,
Wastewater disposal on land can be considered as "appropriate" wastewater treatment technology for many less developed and developing countries. The main advantages of .this technique are the low initial and maintenance costs involved, the effective reduction of the organic load as well as the removal of bacteriological pollution, reuse of nutrients such as nitrogen and phosphorus present in the was,tewater through retention by soil and the increase of the productivity of the soil. Treatment of wastewater by land application has not been practised so far in Turkey. The present study was conducted to investigate the applicability of this method in our country and to predict the results. For this purpose, a 25 meter long channel was constructed and after it was filled with sand, domestic wastewater was applied. The variation of the wastewater and soil characteristics with time and distance were investigated through out the application period. Removal efficiencies obtained are given below: Chemical oxygen demand (COD) 74-84 % - Nitrogen (N) 65-75 Z - Phosphorus (P) 73-92 % - Turbidity 75-80 Z - Total coliform 77.5-82.5 % These results are in full agreement with the results of similar studies conducted elsewhere. The conclusion of the present study is that land disposal on sandy grounds is a method which can be used effectively in many parts of Turkey.
Scale effect of modelling on biogas generation
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1984., 1984.) Çukurova, Recep.; Curi, Kriton,
Anaerobic decomposition of manure i s an outstanding alternative energy source, appropriate for most developing countries. Several studies related to this subject were conducted so far, however, the effect of the size of the inodel on the efficiency obtained was not investigated. The main purpose of the present study was t o investigate, the scale effect on the perfomance of an anaerobic digestion. To achieve this three digesters , each of different size and voluue, were installed and operated under ambient conditions. The results obtained have shown that: 1. The size of the model has as light effect on the efficiency of anaerobic digestion, better performance being obtained in larger model. 2. Any digester can be operated under ambient conditions if proper insulating precautions are taken. 3. Mixing has a positive effect on biogas generation. 4. The positive effect of yeast on anaerobic decomposition is verified .
Efficiency of wastewater treatment by land disposal and its effects on crop productivity
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1985., 1985.) Üstün, Beyza.; Curi, Kriton,
Land application of wastewater is one of the oldest methods used for treatment and disposal of wastes.The main advantages of this technique are the low initial and maintenance costs involved,high Nutrieht recyle capacity, and the increase of crop growth. Because of these factors it is believed that land disposal is an advantageous thechnique for deyelooing countries and is strongly recommended for the rural areas of Turkey. in 1984, a 25 meters long channel was constructed by A-Bavsal in Boğaziçi University's Garden.These Channels were filled with sand and gravel domestic wastewater was applied. The variation of wastewater characteristics with timerdistance and effective size of media were investijated through out the anplication period in 1985. Removal efficiencies obtained are given below: Chemical Oxvqen Demand(C0D) 76% in the Sand bed for 35days - 60% in the Gravel bed for 35days -- Nitrogen (N) 70% in the Sand bed for 35 days - 57% in the Gravel bed for 35days -- Phosnhorus (P) 77% in the Sand bed for 35 days - 64% in the Gravel bed for 35days. The study of crop productivity has been performed at Faculty of Forest of Istanbul University. Its aim was to examine the crop productivity of the media through which wastewater has been disnosed.The best result was obtain from a mixture containing 80% of the media and 20% of soil.
Heavy metal taxicity on blue-green alga
(Thesis (M.S.)- Bogazici University. Institute of Environmental Sciences, 1986., 1986.) Berk, Hüma.; İnel, Yüksel.
In this study, the growth response of Anabaena flos-aquae, which is a filamentous, heterocystous blue-green alga, towards heavy metals i s described. The experiments were long term, batch type experiments, and algae were incubated in media containing Hg(I1) as mercuric chloride (HgC12) ,Cd(II) as cadmium chloride (CdC12), Se(1V) as sodium seleni te (Na2Se03), Ni (11) as nickel chloride (NiCI2.6H20) ,Cr(VI) as potassium chromate(K2Cr04) and As(V) as sodium arsenate (Na2HAs04). 7H20) in solution. Growth i s measured spectrophotometrical ly and optical density is used in the expression of results. In all cases, metals were found to be inhibitory on the growth, the degree of inhibition depending upon the type of the metal ion and the concentration in the medium. I t was found that in media contaminated with 10,20 ppm selenium and 0.2 ppm nickel, the growth of cells failed complelety.
A numerical model for the Marmara sea
(Thesis (M.S.)- Bogazici University. Institute of Environmental Sciences, 1987., 1987.) Albek, Erdem Ahmet.; İnel, Yüksel.
In this study, a numerical model has been developed to predict currents and water levels prevailing in the Marmara Sea. The model is a depth averaged two-layer transient model to adequately simulate stratified flow conditions in the sea. The nonlinear partial differential equations of the model have been solved by using an explicit finite difference scheme and employing a local integral method to reduce truncation and round-off errors and to improve accuracy. Special emphasis has been laid on the prediction of currents and water levels under strong winds.
Valance molecular connectivity model in the prediction of compartmental distribution of selected aromatic pollutants
(Thesis (Ph.D.)- Bogazici University. Institute of Environmental Sciences, 1987., 1987.) Menemenli, G. Feryal.; İnel, Yüksel.
The main purpose of this work is to develop a mathematical model based on the Valance Molecular Connectivity theory which is initiated as an extension of graph theory having its roots especially in structure-activity studies concerning drug-design and toxicity prediction in pharmaceutical chemistry, to evaluate the compartmental distribution of various aromatic pollutants in the environment. During the last decade concerns have been expressed as to the "best way" to assess the potential hazards posed by exposure to chemical substances. In response to these concerns, the chemical group of OECD initiated a hazard assessment project to examine the available methods for hazard assessment of chemicals. The main purpose being to determine how information on theultimate fate and effects of a chemical can be derived from the set of premarket data, the group accepted four models for the estimation of exposure potentials of chemicals within environmental compartments of major concern. Ail of the four models accepted by OECD chemical group was based on the concept of fugacity and essentially needed the following data e molecular weight e water solubility e vapor pressure e soil sorption constant e octanol-water partition coefficient However, the availability and precission of the set of data proposed, especially for chemicals which have rather large and complicated structures was a drawback of these models. Hence, a reasonable model to evaluate this distribution quantitatively without needing such hard-to-gather data would have been a remarkable advance in prediction of environmental hazards that are going to be caused by unknown chemicals irrespective of size and conformation. In this work a new mathematical model (VMCI) based only on the topological characteristics of molecules is deveioped in order to evaluate the distribution of chemicals within various compartments of the environment such as air, soil, water, biota, suspended solids and sediment. The Valance Molecular Connectivity Index, which is the basis of this new model is known to correlate significantly with a number of structure dependent physicochemical properties, and by this wock lt has now been shown to have a high degree of correlation also with water solubilities, vapor pressures and partition coefficients hence wlth the partitioning properties of molecules. As a result, by comparing the two completely different methods of evaluation (VMCI and Level I Fugacity Models) this work proved that it is possible to predict the compartmental distribution of any aromatic compound quantitatively within a high accuracy just by considering the molecular geometry. The superiority of this model compared to fugacity dependent models accepted by OECD lies in the fact that it does not require the physical data such as solubility, vapor pressure or partition coefficient. Relevantly another superiority comes out to be the ability to stay as accurate when even very complicated molecules are investigated while for fugacity dependent models accuracy diminishes due the difficulties in obtaining the experimental data.
Environmental distribution of polychlorinated biphenyls by topology based characteristic root index
(Thesis (Ph.D.)- Bogazici University. Institute of Environmental Sciences, 1990., 1990.) Saçan, Melek Türker.; İnel, Yüksel.
Relationships between a newly developed index -which is based on topological characteristics ofthe molecules and called the Characteristic Root (CR) index- and the environmentally relevant physicochemical properties of the Polychlorinated Biphenyls, namely, aqueous solubility, vapour pressure, Henry's Law Corastants, and octanol-water partition coefficient are discussed. Correlations performed on the congeners clearly demonstrate that the CR index model accurately predicts the physicochelnicaiproperties of PCBs. Highcorrelationcoefficient (r = 0.998) was calculated for the linear one-parameter correlation between the CR index and molecular total surface area. So, the CR index was used in the prediction of pro2erties dependent on tetal surface area. The quality and reliability of the correlations are show to be high enough for environmental applications. Reported experimental physicochemical data of PCBs are tabulated, Recomended values are given for 58 of the 209 congeners, With the available data, it is possible to estimate what percentage of the chemical will be located in the soil, bottom sediments, water and air. The predicted and experimental physicochemical properties of PCBs were used to predict the environmental compartmentalization of these compounds in an evaluative environment using the fugacity approach.
The predicted environmental distribution of selected flame retardant chemicals
(Thesis (M.S.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1991., 1991.) Baysan, Semra.; İnel, Yüksel.
The aim of this study is to calculate environmental equilibrium distributions for selected Flame Retardant Chemicals and thus to indicate where each of them goes and what relative concentrations they adopt in the enviromental compartments. In this study, Mackay's Level I Fugacity Model, based on fugacity that characterizes the escaping tendency from a phase, is used for calculations. The fugacity calculations are applied to an evaluate environment a "unit world" consisting of compartments of homogeneous air, soil, water, biota, suspended solids and sediment. Each compartment is assigned a reasonable volume and properties and the equilibrium distributions of those chemicals are calculated using fugacity capacities, that are calculated from physical and chemical data partition coefficients. When the results are designed to yield priorities for each compartment, it is found that Halognated Flame Retardant Chemicals for the air compartment, Phosphorus Flame Retardant Chemicals in the Sediment and Soil compartments are priorities.
Evaluation of the Eutrophication process in lake İznik
(Thesis (M.S.)- Bogazici University. Institute for Graduate Studies in Science and Engineering, 1993., 1993.) Zakrı, Fawaz.; Akkoyunlu, Atilla.
Lake Iznik is located in the southern east part of Marmara region within the province of Bursa . Its water is of a big importance to the region with a Mediterranean climate, and an annual rainfall ranging between 500 - 750 rom, falling mainly in the period from October to March . This water is used in dry season for irrigation . In this thesis, a physical study of the region is conducted . The physical , chemical and biological parameters were examined at several sites in order to determine the eutrophication state and a suitable model was applied to represent the lake . Lake Iznik was found to be very near to the eutrophic state and the limiting nutrient in the lake was found to be the phosphorus element .
Waste biomass in Turkey and solar drying as a new alternative for its utilization as feed
(Thesis (Ph.D.) - Bogazici University. Institute Environmental Sciences, 1993., 1993.) Tosun, Ayşe.; Saygın, Ömer.
Sources of waste biomass in Turkey were classified in this study. The amounts belonging to the items of the classification were estimated. The current use of these wastes were discussed and it was suggested that the best way to recycle nutritious wastes was using them as feed. Since some of these wastes are high in moisture, it is essential to protect them against bacterial spoilage by drying. Drying, on the other hand, is an energy intensive process. The economical feasibility as well as the ecological benefit of drying wastes by burning fuels is questionable. An economical solution at least for countries with abundant solar insolation would be the use of solar energy for drying. Various methods of solar drying of food wastes were examined. Open air as well as forced air drying gave bacteriologically inadequate products. Therefore, solar boiler dryers, working at 105°C, were constructed. To prevent the observed temperatures higher than 105°C at the later stages, drying was conducted in two stages. While sterilization and removal of most of the water were achieved by boiling in the solar boiler dryer at the first day, open air drying at the second day allowed to obtain a light brown colored product with trace amounts of bacteria and mold. The energy efficiency for vaporization was 85%. Heat losses of the whole dryer due to reflection, convection, and radiation were calculated to be 13%, 7%, and 20%, respectively. Suitability of the material obtained, as animal feed, was tested on broiler chickens. The results indicated that soybean meal protein in broiler diets, can be replaced by the protein of this product up to 40% without any reduction of the weight gain of the birds.|Keywords: Biomass, Food Wastes, Recycling, Solar Drying of Wastes, Feed from Wastes
Investigation of nitrification characteristics of a nitrogenous industrial wastewater
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1994., 1994.) Gökçin, Pınar.; Çeçen, Ferhan.
Treatment of wastewaters containing very high amounts of nitrogen is a problem for industries like the fertilizer industry. Up to date methods like air stripping or ion exchange can also be used in removal of nitrogen but they have certain disadvantages. The main purpose of this thesis was to present another known process used in nitrogen removal. The general concern of the study is to determine if nitrification process could tolerate industrial wastewaters containing high concentrations of nitrogen. In the beginning of the experimental part of the study, sludge previously acclimated to nitrification was introduced to increasing concentrations of ammonium nitrogen. In the second part of the study, wastewater from a fertilizer industry was used in order to detect the removal capacity of the system. Throughout the study effects of pH on the system and the system's tolerance was observed. Data obtained during the study proved that nitrification is a process that behaves according to the zero order kinetics. Finally, the results indicated that a nitrification process can surmount very high amounts of nitrogen if the environmental conditions are idealized.
The characteristics and reuse of Golden Horn surface sediments
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1994., 1994.) Aydın, Zehra Semra.; Karpuzcu, Mehmet.
In this study the characteristics and reuse of Golden Horn surface sediment were investigated. 40 per cent of the water content of the sediment is free and immobilised water, and the remaining 60 per cent is bound water content. In accordance with these results, the high specific resistance value of the sediment indicates its poor dewaterability characteristics. The leachate of the samples does not contain the toxic heavy metals even if the deposits get into contact with acid rain of pH 4. The sediment has strong Cu and Pb adsorption properties. Considering the metal content of the sediment, it is obvious that the sediment is not saturated with these metals. Another important characteristic of the samples IS their high buffering capacity. The reuse of the dried sediment as a clay mixture III brick manufacturing seems possible.|Keywords: Sediment, dewatering, metal adsorption
A study of shipping industry and assessment of environmental impacts in Turkey
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1998., 1998.) Tuzcu, M. Fikret.; Kocasoy, Günay.
In recent years, the importance of the environmental concerns at shipping and the related standards/safety measures have become subject to clear understanding and acceptance of each country at international platforms. The aim of this study was to evaluatelinvestigate the reflections of the international standardization developments at Turkey and the ways for reaching the very strict and internationally requested standards at her shipping industry at once. For this purpose; general evaluation of the prospective Turkish Shipping Industry, its development during the recent years, its current performance in the terms of conforming with the international standards and ways for reaching these standards with a better conformance have been investigated. The necessary steps that Turkey should immediately take during this period have been evaluated by specifically studying the problems of the Turkish Ports that can be defined as evident indicators of the economic power of a country. The results were expressed by analyzing the economic, commercial and technological means of overcoming the sub standardization at Turkish ShippingIPorts. Moreover, 'Pipe-Line' alternative has been suggested instead of 'Straits' alternative with social cost/benefit analysis of marine pollution and other environmental effects that have been studied by evaluating the effects of tanker accidents on environment and human nature.
Trace-level metals and natural organic matter interactions: |oxidative/adsorptive removal pathways
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1999., 1999.) Uyguner, Ceyda Senem.; Bekbölet, Miray.
The destructive removal of humic acids in natural waters has gained increased attention, because these substances are known to be major precursors of carcinogenic disinfection byproducts which are produced during chlorination. Since the conventional treatment methods are expensive and complicated, heterogeneous photocatalytic degradation processes using Ti02 have been applied as an alternative treatment for the destruction of humic acid. This study was conducted to investigate the effects of chromium and manganese ions on the photocatalytic degradation of humic acid (10 mg L-1 ) in aqueous medium at neutral pH conditions (pH=6.7). Bench scale experiments were carried out using titanium dioxide (0.25 mg mL-1 ) as the photocatalyst and Black Light Fluorescent Lamp as the irradiation source. For comparison purposes, the photocatalytic degradation of humic acid was performed both in the presence and absence of metal ions. The degradation was followed by pseudo first order and Langmuir-Hinshelwood kinetics in terms ofColor436, Color4oo, UV280 and UV 254. The presence of chromium and manganese ions resulted in decreased removal rates on the photocatalytic degradation of humic acid compared to the baseline rate of humic acid alone. Pseudo first order reaction rate constants for Color436 and UV254 were found to be 3.86x10-2 min-1 and 2.73x10-2 min-1 in the absence of metal ions. Color436 removal rate constant decreased to 3.13x10-2 min-1 in the presence of 0.10 mg L-1 chromium ion and in the presence of 0.05 mg L-I manganese ion, a value of 3.37xlO-2 min-1 was attained. On the other hand, a similar trend was observed for UV254, the removal rate constant in the presence of chromium was calculated to be the lowest with a value of 2.06x10-2 min-1 whereas, in the presence of manganese it was found to be 2.31xlO-2 min-I. The decrease in the photocatalytic oxidation rate might be explained by the formation of a weak complex between humic acid and the metal ion which might have blocked the active sites on the Ti02 surface. Complimentary adsorption experiments were also performed to evaluate the effect of adsorption intensity on the photocatalytic degradation rates. The results indicated that no significant difference was observed with the adsorption capacity (KF) values, but compared to the other two, the humic acid + manganese system exhibited the highest values.
Dynamic simulation model for long term comprehensive environmental analysis of GAP
(Thesis (Ph.D.)- Bogazici University. Institute of Environmental Sciences, 1999., 1999.) Saysel, Ali Kerem.; Yenigün, Orhan.; Barlas, Yaman.
Integrated development projects based on water resources development, aiming hydropower production and agricultural modernization have many potential impacts on social and natural environments. Southeastern Anatolian Project (GAP), located in Southeast Turkey, comprising 10% of Turkish lands, targeting irrigation schemes on 1.7 million hectare fertile lowlands and 7400 MW hydropower production on Euphrates and Tigris would have many social and environmental consequences. In this study, potential environmental problems suggested by GAP, questions related with utilization of water resources, land degradation, agricultural pollution and land use are analyzed in systems perspective, focusing on the integrity of environmental, social and economic issues. With this aim, GAP S 1M, a dynamic simulation model is developed to trace long term trajectories of selected parameters, representing the relevant aspects of GAP's social, economic and natural environment. Based on a "systemic" problem definition, GAPSIM simulates the development rate of irrigation schemes, hydropower production with respect to changing irrigation releases, water availability on farmlands, crop selection and production, salinization, erosion, pesticide and fertilizer consumption, rangeland and forest quality, urbanization and population dynamics in GAP during 1990-2030 period, which comprises water facilities construction process. GAPSIM is validated, first "structurally", according to the validation tests suggested by the literature and then, model "behavior" is calibrated with respect to data available for the period 1990-1998. GAPSIM provides a dynamic simulation platform where several scenarios and policy analyses concerning GAP environment can be executed in order to arrive at an improved understanding of GAP as a socio-environmental system. Scenario and policy runs on GAPSIM reveal that, increased intensity of the most evapotranspirant crop cotton on GAP fields may cause significant water scarcity, which hinders the development rate of irrigation into new acres and inhibits crop yields by decreased water delivery to individual farms.
Biodiversity analysis of marine demersal invertebrate fauna in the princess islands region
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 1999., 1999.) Hüseyinoğlu, Fatih.; Furman, Andrzej.
A study for the inventory of the diversity of invertebrate species habited in the Princess Islands region, istanbul was conducted to cover the gap between alike studies conducted all over the top biodiversity centres. The mentioned area was one of the most diverse areas in temperate waters. The biodiversity due to over population has been decreased in the area, and this study was made in comparison with the past study. Princess Islands region and Bosphorus Strait was studied in detail in 1952 by Muzaffer Demir, which was the starting point for this comparative study in the area after half a century. Between Muzaffer Demir and this study, the studies conducted over invertebrate fauna in the Sea of Marmara are insufficient. The main concepts as the definitions, value and conservation of biodiversity are also given followed by the key notions of the current trends in conservation biology. Descriptions of the new species and keystone species with their pictures are also added. There are two groups of islands: Inhabited and desolate (see Map3.1 and Map 3.2). The inhabited islands are 6km far from the shore and domestic wastes are discharged directly to the sea. The desolate islands are 12km far from the shore and comparably have greater biodiversity than the inhabited islands coasts which are being polluted both by istanbul wastes because they are nearer and domestically. Several dives were done in various sites to observe the species in their habitats. Comparative which-and-where tables of the demersal invertebrate phyla are added with a scale of abundance that will help future studies. 9 new species were recorded that were not recorded before, and many probable extinctions were noted.
The summer populations of cave-dwelling bat species of Çatalca-Kocaeli region and environmental region and environmental factors that influence their distribution
(Thesis (M.S.)- Bogazici University. Institute of Environmental Sciences, 2000., 2000.) Bilgin, İbrahim Raşit.; Furman, Andrzej.
The summer population of cave dwelling-bat species in Catalca-Kocaeli Region was surveyed between May-August 1999. The effects of geographical location, habitat, and temperature were studied as possible factors in determining the distribution patterns of the bat species in these caves. Nine out of the 11 caves were studied for the first time with regard to the assessment of bat populations inside. Three maternity colonies were identified for Rhinolophus ferrumequinum, R euryale and Minioptems schreiberszi in three different caves. The statistical analysis based on geographical coordinates, and species distribution hinted that Bosphorus might be acting as a natural barrier limiting migration and gene flow between Catalca and Kocadi regions. Hence it may be more correct to treat Catalca and Kocaeli regions separately in terms of species occupancy. The critical habitat types influencing species distribution were traditional arable land, pond, heathland, and maquis. River, riparian treeline, pasture, broadleaved woodland md broadleaved woodmd/pasture edge were the common habitat types recorded for all of the bat species. Habitat surveys around the caves indicated that M. schreibersii might be able to utilize a greater number, and Large Myotis a lesser number of different habitat types, compared to the other species studied. Average temperature in the caves was the weakest contributing factor far explaining the distribution patterns of the species.|Keywords: Chiroptera, Cave, Habitat, Temperature, Turkey
Oxidative treatment of antibiotics in pharmaceutical effluents
(Thesis (M.S.) - Bogazici University. Institute of Environmental Sciences, 2002., 2002.) Ötker, Havva Merih.; Balcıoğlu, Işıl.
Antibiotics are intensively used both in veterinary and human medicine and up to 90 per cent they are excreted through urine and feces into municipal sewage after administration. They can also enter to the sewage treatment plants through the wastewater generated from the formulation process in pharmaceutical industry. Since antibiotic containing effluents are inert towards conventional biotreatment, antibiotics may reach to the aquatic environment and thus such effluents require an oxidative pretreatment. Cephalosporine (I) and penicillin (II) group human antibiotics and quinolone group veterinary antibiotic in synthetically prepared pharmaceutical formulation effluents were treated by ozonation in order to improve their biodegradability. The effects of pH, initial antibiotic concentration, dose of H2O2 and applied ozone doses were investigated on treatment performance. Elevating the reaction pH, inlet ozone concentration and H2O2 dose resulted in an enhancement on treatment efficiencies of all antibiotic formulation effluents. While in the veterinary antibiotic effluent BOD5/COD ratio was increased from 0.077 to 0.38 with an applied O3 dose of 2960 mg/L h, at pH=7, for human antibiotic I and human antibiotic II, BOD5/COD ratio was increased from 0 to 0.1 and 0.27 respectively. In order to correlate biodegradability results with a structure of antibiotics, degradation rates of antibiotics were related with energies required for the degradation by H-abstraction. Combination of ozone with UV, accelerated aromaticity removal from 63 to 83 per cent, and oxygen uptake rate from 0.21 to 0.28 mg/L min for veterinary antibiotic (CODi=900 mg/L), however, did not appear to be more effective than applying mere ozonation in terms of COD removal rates.
Health-care waste management of the hospitals in the European side of Istanbul
(Thesis (M.S.)-Bogazici University. Institute of Environmental Sciences, 2004., 2004.) Zeren, Binnur Aylin.; Kocasoy, Günay.
The inefficient management and disposal of the health-care wastes generated at the health-care institutions is the significant problems faced in the İstanbul City of Turkey. This study will refer to the development of an integrated health-care waste management plan at the European Side of İstanbul City. In the scope of the study, firstly the existing institutional and legislative framework are reviewed and the health-care institutions generating the wastes are surveyed through the prepared questionnaires, comprehensive field research and personnel interviews. By the obtained data, the inventory about the amounts, types and sources of the health-care wastes is developed. The infectious composition of the health-care wastes is also determined by the conducted microbiological analyses. To analyze the possible cost reductions, the optimum waste prevention and minimization techniques are suggested for the health-care institutions. For the problem of the transportation and disposal of these wastes; the optimum transportation routes are prepared and the appropriate treatment and disposal technologies are determined. The final stage is planning and proposing a health-care waste management center which can be used as a basis for the other cities in Turkey. All the graphs, tables and maps related to the proposed suggestions are illustrated in the study.
Integrated ozone and biotreatment of pulp mill effluent
(Thesis (M.S.)-Bogazici University. Institute of Environmental Sciences, 2005., 2005.) Saraç, Canan.; Balcıoğlu, Işıl.
In this study, the effluents from the biggest pulp and paper plant in Turkey that having amultistage chlorine bleaching process were treated by an integrated process consisted ofozonation and activated sludge processes to enhance the biodegradability and increase the quality of effluent.In the first part of the study, ozonation process was applied to CEHDED and CEH stagebleaching effluents. The effects of fibre type, pH, H2O2, and ozone dose were investigated ontreatment performance of ozonation process. Significant COD and color removals wereachieved by increasing ozonation pH of combined bleaching effluents to a value of 12. The highest treatment efficiency was achieved by the O3/H2O2/pH=7 process with 1632 mg/Lozone dose for CEHDED effluent. While 41 per cent COD removal was obtained by applyingO3/pH=7 process to CEHDED effluent, COD removal was increased to 57 per cent by the addition of 15 mM H2O2. Although ozonation of CEHDED effluent at pH=7 resulted in only amoderate alteration in BOD5/COD ratio, O3/H2O2 /pH=7 treatment increased the BOD5/CODratio from 0.2 to 0.4. Almost complete color removal was also achieved by O3/H2O2 /pH=7treatment. In the second part of the study, activated sludge process was applied to pulp milleffluent. While for the raw effluent overall CODs removal efficiency of biological processwas 61 per cent, it was 77 per cent for the pulp mill effluent, which contained the pretreated(O3/H2O2/pH=7) CEHDED effluent. Furthermore, AOX removal rate was increased from 39 to 70 per cent by the pretreatment of combined bleaching effluent.

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