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ozonization
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Modeling of Ground-Level Ozone Concentrations in Tehran using CMAQ Model
, M.Sc. Thesis Sharif University of Technology ; Arhami, Mohammad (Supervisor)
Abstract
Every year, air pollution is causing immense harm to humans and the environment. To cause Air pollution, several factors are involved. Among these are the sources of emissions such as factories, power plants and Cars, meteorological factors such as temperature and wind speed and geographical conditions such as altitude, postal and looming around the area, land slope and soil type region. The aim of this study is to identify factors that affect the ozone concentration in Tehran, which could help identifying other secondary pollutants. For this purpose, a combination tailored to the geography of Tehran using CMAQ-WRF-SMOKE-made programs. This model includes four intervals each of which lasting...
Study of the Effect of Ozonation in Reducing Mambrane Fouling
, M.Sc. Thesis Sharif University of Technology ; Shaygan, Jallaledin (Supervisor) ; Hazrati, Hossein (Co-Advisor)
Abstract
Membrane bioreactors (MBRs) are a combination of activated sludg and mebrane technology. MBRs have been widely used as an advanced process for urban and industrial wastewater-treatment in recent years. Membrane fouling is the main issue that limits their performance and therefor, many studies have concentrated on testing different ways to mitigate the fouling. Ozonation process, that has been proved to reduce the MBR fouling, is studied in this project. Ozonation can provide the conditions for flocculation and therefor improves mixed-liqure properties. Ozon at two concentrations, 0.2 and 0.9 mg/lit was tested. Although results show little change in COD (chemical oxygen demand), but membrane...
Labratoary Studies of Ozonation Pretreatment for Anaerobic Digestion of Waste Thickened Active Sludge
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Manouchehr (Supervisor) ; Ghasemi, Shahnaz (Supervisor)
Abstract
The best method for stabilizing sludge is anaerobic digestion, In addition to reducing the amount of volatile solids; it produces biogas, which can be considered as a sustainable energy source for wastewater treatment plants. However, the most important factor limiting the process of digestion is the sludge hydrolysis, the best way to increase the speed of hydrolysis is to pre-treatment the sludge before entering the digester; One of the most effective pretreatment methods is pre-treatment by ozone gas, This gas, which is highly unstable, quickly reacts with the wall of the bacterial cell and oxidizes it due to its high oxidizing properties And accelerates the process of sludge hydrolysis....
Modelling and Prediction Air Polutants Level in Tehran Using Dynamic Neural Networks
, M.Sc. Thesis Sharif University of Technology ; Erhami, Mohammad (Supervisor)
Abstract
In parallel to the growing of population in Tehran metropolitan, air pollution in this city has become to a major problem. From which high concentration of pollutants have adverse effects on public health, accurate estimating and forecasting of concentrations for several days ahead, can provide the possibility to implement the management measures to reduce hazard and risks. Among the air pollution models, application of statistic models based on neural network in comparison to the traditional deterministic models are easier and less costly. In most studies, static models use a classical single MLP to predict one step ahead. For this purpose ANN models are required to estimate next value of...
Copper Selective Leaching from Sarcheshmeh Reverberatory Furnace Dusts
, M.Sc. Thesis Sharif University of Technology ; Askari, Masoud (Supervisor)
Abstract
In this study, leaching of Sarcheshmeh Reverberatory Furnace Dust was investigated in the H2SO4-O3 media. Response surface methodology based on central composite face-centered design (RSM-CCF), was applied to optimize the operating parameters. The optimum conditions to obtain the main goal of maximum copper and minimum iron dissolution from dust were identified to be temperature of 30˚C, leaching time of 3hr, initial pH of 0.5, pulp density of 20% and ozone flow rate of 1g/h. The copper and iron concentrations of leaching solution were found to be 27.11 and 0.89983 g/L under the optimum conditions, respectively. The results showed that selective copper extraction from the dust could be...
Modeling Gaseous Air Pollutants Concentration in Tehran Using Artificial Neural Network and Land Use Regression
, M.Sc. Thesis Sharif University of Technology ; Mohammad Arhami (Supervisor) ; Amini, Zahra (Co-Supervisor)
Abstract
In this thesis the hourly concentration of different gaseous air pollutants in Tehran is modeled using Land Use Regression (LUR) and Artificial Neural Network, separately. Both models are provided with the same set of input data; the first step is to find these data. Since traffic affects air pollution, information about traffic conditions is one of the main inputs in air pollution modeling. Therefore, to obtain traffic information, in this thesis, first a novel method is developed to extract and analyze Google Maps traffic data. In this method, image processing is used along with the Geographic Information System (GIS) to count the number of pixels of different traffic colors for each road...
Comparison of ozonation and aeration methods in removal of naphthalene from aqueous solution
, Article Asian Journal of Chemistry ; Volume 25, Issue 16 , 2013 , Pages 9135-9137 ; 09707077 (ISSN) ; Borghei, S. M ; Hassani, A. H ; Mirbagheri, S. A ; Javid, A. H ; Sharif University of Technology
2013
Abstract
High molecular mass of naphthalene make it non-biodegradable and the biological methods for treated the pollutant are much time consuming. In this paper, two methods of ozonation and aeration are used to remove naphthalene. Because of the industrial wastewater has a great range of pH, in this study different concentrations of soluble naphthalene are placed in variable pH conditions, different contact times and changes in amount of aeration and ozonation. ANOVA results indicated a significant difference between two methods. The average removal of naphthalene by use of ozonation is 55 % and 37 % for aeration. As results, the best conditions that naphthalene are removed is in acidic environment...
Contribution of the Middle Eastern dust source areas to PM10 levels in urban receptors: Case study of Tehran, Iran
, Article Atmospheric Environment ; Volume 75 , 2013 , Pages 287-295 ; 13522310 (ISSN) ; Arhami, M ; Tajrishy, M ; Sharif University of Technology
2013
Abstract
The origins and evolution of the Middle Eastern dust storms which frequently impact the residents of this arid region were studied. A methodology was adapted and developed to identify the desert regions of potential dust sources and determine their contributions to PM10 concentrations in the highly-populated receptor city of Tehran, Iran. Initially, the episodes of regional dust intrusion and the resulting amounts of increase in the particulate concentrations during these episodes were determined using a statistical analyzing methodology. The dust episodes were also inspected with the aerosol index information from the Ozone Monitoring Instrument (OMI). The Hybrid Single-Particle Lagrangian...
Predicting hourly air pollutant levels using artificial neural networks coupled with uncertainty analysis by Monte Carlo simulations
, Article Environmental Science and Pollution Research ; Volume 20, Issue 7 , 2013 , Pages 4777-4789 ; 09441344 (ISSN) ; Kamali, N ; Rajabi, M. M ; Sharif University of Technology
2013
Abstract
Recent progress in developing artificial neural network (ANN) metamodels has paved the way for reliable use of these models in the prediction of air pollutant concentrations in urban atmosphere. However, improvement of prediction performance, proper selection of input parameters and model architecture, and quantification of model uncertainties remain key challenges to their practical use. This study has three main objectives: to select an ensemble of input parameters for ANN metamodels consisting of meteorological variables that are predictable by conventional weather forecast models and variables that properly describe the complex nature of pollutant source conditions in a major city, to...
Dual catalytic function of the task-specific ionic liquid: Green oxidation of cyclohexene to adipic acid using 30% H2O2
, Article Chemical Engineering Journal ; Volume 221 , April , 2013 , Pages 254-257 ; 13858947 (ISSN) ; Hashemi, M. M ; Sharif University of Technology
2013
Abstract
The sole industrial process which currently used for adipic acid production is nitric acid oxidation of either cyclohexanol or cyclohexanol/cyclohexanone mixture. Emission of greenhouse nitrous oxide (N2O) gas from this process strongly contributes to global warming, resulting in acid rain and ozone depletion. Herein, we report a catalytic application of a novel dual task-specific ionic liquid (an ionic liquid with two catalytic functions) for oxidation of cyclohexene to adipic acid using 30% hydrogen peroxide. The catalyst showed desirable activity toward oxidation of cyclohexene and some cyclic olefins to produce their corresponding dicarboxylic acids
Localized surface plasmon resonance sensor for simultaneous kinetic determination of peroxyacetic acid and hydrogen peroxide
, Article Analytica Chimica Acta ; Volume 762 , 2013 , Pages 87-93 ; 00032670 (ISSN) ; Hormozi Nezhad, M. R ; Khodaveisi, J ; Dashti, R ; Sharif University of Technology
2013
Abstract
A new sensor for simultaneous determination of peroxyacetic acid and hydrogen peroxide using silver nanoparticles (Ag-NPs) as a chromogenic reagent is introduced. The silver nanoparticles have the catalytic ability for the decomposition of peroxyacetic acid and hydrogen peroxide; then the decomposition of them induces the degradation of silver nanoparticles. Hence, a remarkable change in the localized surface plasmon resonance absorbance strength could be observed. Spectra-kinetic approach and artificial neural network was applied for the simultaneous determination of peroxyacetic acid and hydrogen peroxide. Linear calibration graphs were obtained in the concentration range of (8.20×10-5 to...
Electrocardiographic ST-segment depression and exposure to traffic-related aerosols in elderly subjects with coronary artery disease
, Article Environmental Health Perspectives ; Volume 119, Issue 2 , Feb , 2011 , Pages 196-202 ; 00916765 (ISSN) ; Gillen, D. L ; Tjoa, T ; Staimer, N ; Polidori, A ; Arhami, M ; Sioutas, C ; Longhurst, J ; Sharif University of Technology
2011
Abstract
Background: Air pollutants have not been associated with ambulatory electrocardiographic evidence of ST-segment depression ≥ 1 mm (probable cardiac ischemia). We previously found that markers of primary (combustion-related) organic aerosols and gases were positively associated with circulating biomarkers of inflammation and ambulatory blood pressure in the present cohort panel study of elderly subjects with coronary artery disease. Objectives: We specifically aimed to evaluate whether exposure markers of primary organic aerosols and ultrafine particles were more strongly associated with ST-segment depression of ≥ 1 mm than were secondary organic aerosols or PM 2.5 (particulate matter with...
Degradation of humic acids through heterogeneous catalytic ozonation with bone charcoal
, Article Reaction Kinetics, Mechanisms and Catalysis ; Volume 100, Issue 2 , 2010 , Pages 471-485 ; 18785190 (ISSN) ; Asgari, Gh ; Hashemian, S. J ; Moussavi, G ; Sharif University of Technology
2010
Abstract
Catalytic ozonation has recently been used as a new means of contaminant removal from water and wastewater. In this study, bone charcoal (BC), a new catalyst prepared under laboratory conditions, was used to catalyze the ozonation of humic substances (HS) in aqueous solutions. The catalytic effect of bone charcoal and the relevant parameters of this ozonation process (solution pH, temperature, scavenger effect, humic acids concentration and BC dosage) were investigated. In the catalytic ozonation experiments, the degradation kinetics was investigated. The reaction rate and the rate constant were determined. The results showed that using a BC catalyst in the ozonation of HS produced a 1.43-...
Application of ozone treatment and pinch technology in cooling water systems design for water and energy conservation
, Article International Journal of Energy Research ; Volume 34, Issue 6 , 2010 , Pages 494-506 ; 0363907X (ISSN) ; Gharaie, M ; Parand, R ; Panjeshahi, E ; Sharif University of Technology
2010
Abstract
Re-circulating cooling water systems offer the means to remove heat from a wide variety of industrial processes that generate excess heat. Such systems consist of a cooling tower and a heat-exchanger network that conventionally has a parallel configuration. However, reuse of water between different cooling duties allows cooling water networks to be designed in a series arrangement. This results in performance improvement and increased cooling tower capacity. In addition, by the integration of ozone treatment into the cooling tower, the cycle of concentration can be increased. The ozone treatment also dramatically reduces the blow-down that, in turn, is environmentally constructive. In this...
Copper recovery from reverberatory furnace flue dust
, Article International Journal of Mineral Processing ; Volume 157 , 2016 , Pages 205-209 ; 03017516 (ISSN) ; Askari, M ; Sharif University of Technology
Elsevier, B. V
2016
Abstract
In this study, leaching of reverberatory furnace dust at Sarcheshmeh was investigated in H2SO4-O3 medium. Response surface methodology based on central composite face-centered design (RSM-CCF) was applied to optimize the operating parameters. The optimal conditions to achieve the principle objectives of maximizing copper dissolution and minimizing iron dissolution from dust were identified to be a temperature of 30 °C, a leaching time of 3 h, an initial pH of 0.5, a pulp density of 20%, and an ozone flow rate of 1 g/h. Under the optimum conditions, the copper and iron concentrations in the leaching solution were found to be 27.11 and 0.90 g/L, respectively. The results showed that selective...
Heterogeneous catalytic ozonation by Nano-MgO is better than sole ozonation for metronidazole degradation, toxicity reduction, and biodegradability improvement
, Article Desalination and Water Treatment ; Volume 57, Issue 35 , 2016 , Pages 16435-16444 ; 19443994 (ISSN) ; Bahrami Asl, F ; Farzadkia, M ; Esrafili, A ; Salahshour Arian, S ; Khazaei, M ; Dadban Shahamat, Y ; Zeynalzadeh, D ; Sharif University of Technology
Taylor and Francis Inc
2016
Abstract
Abstract: In the current paper, the removal efficiency of metronidazole (MNZ) using a catalytic ozonation process (COP) in the presence of magnesium oxide nanocrystals, as a catalyst, was investigated in deionized water and compared with a sole ozonation process (SOP). The influence of several operational factors on both removal processes was evaluated: solution pH, MgO dosage, initial MNZ concentration, and reaction time. Biodegradability improvement, mineralization rate, oxidation intermediates, and toxicity were also studied for the COP. The results showed that MgO nanocrystals accelerated MNZ removal compared to the SOP. The optimum pH for both SOP and COP was obtained at 10 and optimum...
Ozone concentration forecasting with neuro-fuzzy approaches
, Article ICSCCW 2009 - 5th International Conference on Soft Computing, Computing with Words and Perceptions in System Analysis, Decision and Control, 2 September 2009 through 4 September 2009, Famagusta ; 2009 ; 9781424434282 (ISBN) ; Mahjoob, M. J ; Zarringhalam, R ; Miranian, A ; Sharif University of Technology
Abstract
Forecasting is a challenging problem in highly nonlinear dynamic systems. The main goal in development of forecasting models in complex systems is to produce a model that can accurately behave similar to the main system. In problems such as air pollution forecasting, the presence of uncertainties and nonlinearities affects the model's precision. In this paper, ozone concentration, which is well-known as an index for air pollution is forecasted using neuro-fuzzy models. Causal variables are integrated in the models in order to enhance the model's performance. The results are compared to a fuzzy logic approach to demonstrate reliability and accuracy of the proposed model using real observed...
Spatiotemporal description of BTEX volatile organic compounds in a middle eastern megacity: tehran study of exposure prediction for environmental health research (Tehran SEPEHR)
, Article Environmental Pollution ; Volume 226 , 2017 , Pages 219-229 ; 02697491 (ISSN) ; Hosseini, V ; Schindler, C ; Hassankhany, H ; Yunesian, M ; Henderson, S. B ; Künzli, N ; Sharif University of Technology
Abstract
The spatiotemporal variability of ambient volatile organic compounds (VOCs) in Tehran, Iran, is not well understood. Here we present the design, methods, and results of the Tehran Study of Exposure Prediction for Environmental Health Research (Tehran SEPEHR) on ambient concentrations of benzene, toluene, ethylbenzene, p-xylene, m-xylene, o-xylene (BTEX), and total BTEX. To date, this is the largest study of its kind in a low- and middle-income country and one of the largest globally. We measured BTEX concentrations at five reference sites and 174 distributed sites identified by a cluster analytic method. Samples were taken over 25 consecutive 2-weeks at five reference sites (to be used for...
Fouling control mechanism by optimum ozone addition in submerged membrane bioreactors treating synthetic wastewater
, Article Journal of Environmental Chemical Engineering ; Volume 6, Issue 6 , 2018 , Pages 7294-7301 ; 22133437 (ISSN) ; Hazrati, H ; Shayegan, J ; Sharif University of Technology
Abstract
In this paper, the effect of ozone on membrane fouling of membrane bioreactor (MBR) systems was investigated. Sludge specification such as soluble microbial product (SMP), extracellular polymeric substance (EPS), viscosity, particle size distribution (PSD), microscopic observations and sludge volume index (SVI) in presence of ozone were determined. Further, EPS, Fourier-transform infrared (FTIR) analysis, excitation-emission matrix (EEM) fluorescence spectroscopy, and gel permission chromatography (GPC) are considered to determine cake layer characteristics. The results indicated COD removal did not show significant difference with ozonation. Ozone also increases the particle size and...
A novel regression imputation framework for Tehran air pollution monitoring network using outputs from WRF and CAMx models
, Article Atmospheric Environment ; Volume 187 , 2018 , Pages 24-33 ; 13522310 (ISSN) ; Karimi, S ; Hosseini, V ; Yazgi, D ; Torbatian, S ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Missing or incomplete data in short or long intervals is a common problem in measuring air pollution. Severe issues may arise when dealing with missing data for time-series prediction schemes or mean analysis. This study aimed to develop a new regression imputation framework to impute missing values in the hourly air quality data set of Tehran and enhance the applicability of Tehran Air Pollution Forecasting System (TAPFS). The proposed framework was designed based on three types of features including measurements of other stations, WRF and CAMx physical models. In this framework, elastic net and neuro-fuzzy networks were efficiently combined in a two-layer structure. The framework was...