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Choosing a Suitable Microalgae for Bioremediation of Heavy Metals Regarding Iran's Clamate
, M.Sc. Thesis Sharif University of Technology ; Yaghmaei, Soheyla (Supervisor)
Abstract
The pollution of water resources with heavy metals as a result of industrial activities threatens the lives of all living organisms. Therefore, separation of heavy metals from wastewater before entering our invironment is very important. Various chemical and physical methods such as absorption, chemical precipitation, extraction by solvent and ion exchange can be used to separate heavy metals but each of these methods have their own problems such as imperfect separation of heavy metals, need for expensive facilities and refining systems, high energy consumption and leaving pollutant residuals that need to be separated. On the other hand, the methods mentioned above can not separate heavy...
A Study of Practical Methods for Petroleum Hydrocarbons Removal from Polluted Groundwaters in a Refinery
, M.Sc. Thesis Sharif University of Technology ; Kariminia, Hamid Reza (Supervisor)
Abstract
Petroleum based products are the major sources of energy for industry and daily life, With the development of social economy, the demands of the oil have increased dramatically. Petroleum hydrocarbons can cause environmental pollution during various stages of production, transportation, refining and use. Releases of petroleum products(e.g., gasoline, diesel, fuel oil) from aboveground and underground storage tanks or transport pipelines are the major causes of the environment pollution.The major constituents of petroleum hydrocarbons are biodegradable. Many soil microorganisms transform oil hydrocarbons into nontoxic compounds or mineralize them to inorganic compounds. In situ...
Indoor Noise Pollution Modeling: A Case Study on Resalat Tunnel
, M.Sc. Thesis Sharif University of Technology ; Vaziri, Manouchehr (Supervisor)
Abstract
Noise or noise pollution, is defined as an unwanted sound, produced mostly by motor vehicles in urban areas. If the noise exceeds its limit, adverse effects on users and citizens are expected. Thus the assessment of the noise level and its comparison with allowable values is mandatory. Traffic induced noise depends upon different factors such as traffic, weather, and, sound barriers. Noise pollution study has a long history all over the world. Many studies, mostly representing the outdoor noise pollution models, have been done in recent years. This paper presents an assessment of traffic-induced noise in a heavily traveled tunnel, locally referred to as Resalat tunnel, which is located in...
Mathematical Modeling of Upflow Biofilm Reactor for Wastewater Treatment
, M.Sc. Thesis Sharif University of Technology ; Yaghmaee, Soheila (Supervisor) ; Kariminiaye Hamedani, Hamid Reza (Supervisor)
Abstract
By increasing of population, migration to urban area and industrial development, the concern of environmental pollution becomes more important. Wastewaters are one of the polluting agents which should be collected, treated and reused in a safe and healthy condition. Generally wastewater treatment systems are classified into two major groups, namely aerobic and anaerobic treatment systems.Anaerobic fixed bed reactors are used for decreasing the organic load of wastewater. Enhancement of microbial retention time by attaching the organisms to packings is the most significant advantage of this bioreactor which increases the removal efficiency of organic materials of strength wastewater.In this...
Evaluation of Permeable Pavement in Removing Pollutants from Surface Runoff
, M.Sc. Thesis Sharif University of Technology ; Tajrishi, Masoud (Supervisor) ; Nazari Alavi, Alireza (Supervisor)
Abstract
Urbanization expansion increases impermeable surfaces and ultimately produces more runoff from urban surfaces. The runoff in the urban streets moves the pollution with high levels from the city and then collects into channels where they are transported into the water courses. The most important factor in runoff polluting is sediments. If you remove sediments from runoff, their quality will be improved. One of the effective systems to reduce sediments from the surface runoff is permeable pavement. In this study a simulator system is used. The sample of permeable pavement analysed consisted of two layers of geotextile beddig, filter granular layer (2.36 to 4.75mm), subbase granular layer (4.75...
Projecting emission reductions from prospective mobile sources policies by road link-based modelling
, Article International Journal of Environment and Pollution ; Volume 53, Issue 1-2 , 2013 , Pages 87-106 ; 09574352 (ISSN) ; Arhami, M ; Sharif University of Technology
2013
Abstract
A methodology was developed to project total vehicular emissions from different emission reduction policies for the light-duty vehicles in the roads network of Tehran, Iran. A road-link-based model was constructed based on a bottom-up approach by coupling COPERT emission functions with the travel demand model of EMME/2. Results showed total emission from the studied network was largely impacted by vehicles' technology and age, speeds in the links, and fuel type. The proper transportation management to reduce the part of passenger cars and improve traffic flow also leads to a significant drop in the emission, e.g., emission decreased by 43% from 20% traffic volume reduction. Results indicated...
Biodegradation of phenol from a synthetic aqueous system using acclimatized activated sludge
, Article Arabian Journal of Geosciences ; Volume 6, Issue 10 , 2013 , Pages 3847-3852 ; 18667511 (ISSN) ; Doulati Ardejani, F ; Marandi, R ; Rafiee pur, S ; Sharif University of Technology
2013
Abstract
Phenol is one of the aromatic hydrocarbons. Phenol and its derivatives are highly toxic. These pollutants can be observed in the effluents of many industries. This research investigates the removal of phenol by the use of activated sludge in a batch system. The effects of influencing factors on biodegradation efficiency have been evaluated. The main factors considered in this study were the volume of acclimatized activated sludge inoculation, pH, temperature, and initial concentration of phenol. The inoculation volumes of 1, 3, and 5 mL of acclimatized activated sludge were taken into account. Different pH values of 3, 5, 7, 9, and 11 were examined. The experiments were conducted for...
Optimization of conditions in ultrafiltration treatment of produced water by polymeric membrane using Taguchi approach
, Article Desalination and Water Treatment ; Volume 51, Issue 40-42 , 2013 , Pages 7499-7508 ; 19443994 (ISSN) ; Rekabdar, F ; Hemmati, M ; SafeKordi, A. A ; Ahmadi, M ; Sharif University of Technology
Desalination Publications
2013
Abstract
In this study, the ultrafiltration of produced water was studied using a two-stage ultrafiltration process. In the first stage, the influences of operating parameters, including transmembrane pressure, temperature, and cross-flow velocity on the amount of flux decline caused by membrane fouling, were investigated using a polymeric membrane. In order to design the experiments and optimize the experimental results, the Taguchi method was applied. L9 (33) orthogonal array for experimental planning and the smaller-the-better response category was selected to obtain optimum conditions because the lowest flux decline was our aim. Analysis of variance was used to determine the most important...
Biofiltration of hexane vapor: Experimental and neural model analysis
, Article Clean - Soil, Air, Water ; Volume 39, Issue 9 , 2011 , Pages 813-819 ; 18630650 (ISSN) ; Halladj, R ; Saber, M ; Ferdowsi, M ; Nasernejad, B ; Sharif University of Technology
Abstract
Biofiltration is a commonlypracticed biological technique to remove volatile compounds from waste gas streams. From an industrial view-point, biofilter (BF) operation should be flexible to handle temperatures and inlet load (IL) variations. A compost BF was operated at different temperatures (30-45°C) and at various inlet loading rates (ILR; 8-598gm -3h -1) under intermittent loading conditions. Complete removal of n-hexane was observed at 30 and 35°C at ILRs up to 330gm -3h -1. Besides, 20-75% of the pollutant was removed at 40°C, corresponding to the different ILs applied to the BF. Increasing the temperature to 45°C decreased the removal efficiency (RE) significantly. A feed forward...
Combination of artificial neural networks and genetic algorithm-gamma test method in prediction of road traffic noise
, Article Environmental Engineering and Management Journal ; Volume 14, Issue 4 , April , 2015 , Pages 801-808 ; 15829596 (ISSN) ; Ghaiyoomi, A. A ; Teshnehlab, M ; Ashlaghi, A. T ; Abbaspour, M ; Nassiri, P ; Sharif University of Technology
Gh. Asachi Technical University of Iasi
2015
Abstract
Neural Networks (FFNNs) that are trained with the Levenberg-Marquardt back-propagation algorithm were used. Models were evaluated using mean squared error (MSE) and coefficient of determination (R2) as statistical performance parameters. In traffic noise modelling, the noise level at a receptor position due to the source of traffic emission is modelled as a function of the traffic conditions, road gradient, road dimensions, speed and height of buildings around the road. The curse of dimensionality problems is caused by the large number of input variables in the ANN model. The Hybrid Genetic Algorithm-Gamma Test (GA-GT) as a data pre-processing method for determining adequate model inputs was...
Assessment of jajrood river watershed microbial pollution: Sources and fates
, Article Environmental Engineering and Management Journal ; Volume 9, Issue 3 , 2010 , Pages 385-391 ; 15829596 (ISSN) ; Tajrishy, M ; Jamshidi, M ; Sharif University of Technology
2010
Abstract
The Jajrood River watershed is on of the main drinking water resurces of Tehran, the capital city of Iran. In addition it provides many recreational usages. However, a variety of microbial pollutions is commonly perecived in the Jajrood River, among them a high concentration of coliform group bacteria that has caused strong concerns. In this article, different aspects of microbial pollution as well as the main microbial pollution sources in the region are discussed. Coliform group bacterial die-off rates have been evaluated as the key parameters that govern bacterial fate in the watershed and were estimated using both laboratory and field data investigations. The high values of the bacterial...
Examining some potential actions in mitigating gaseous emissions from vehicles, case study: Tehran
, Article Air Quality, Atmosphere and Health ; Volume 9, Issue 8 , 2016 , Pages 909-921 ; 18739318 (ISSN) ; Mir, H. M ; Sharif University of Technology
Springer Netherlands
Abstract
Pollutant emission from vehicles is known as a major air pollution source in metropolitan areas. Efficiency of several solutions was quantified and compared to introduce the best solution for decreasing greenhouse gases and air pollutant emissions: (1) inspection and maintenance (I/M) of vehicles, (2) restriction of air conditioner usage, (3) injecting better quality fuel (removing sulfur), and (4) replacing older vehicles with new ones were modeled by International Vehicle Emissions (IVE) model as potential solutions. Restricting air conditioner usage makes an insignificant contribution in pollutants’ emission. The idle inspection/ maintenance system can reduce carbon monoxide (CO) and...
Preparation and evaluation of chitosan-coated eggshell particles as copper(II) biosorbent
, Article Desalination and Water Treatment ; Volume 57, Issue 4 , 2016 , Pages 1693-1704 ; 19443994 (ISSN) ; Khodabakhshi Soreshjani, F ; Bakhshi, H ; Sharif University of Technology
Taylor and Francis Inc
Abstract
Preparation and evaluation of chitosan-coated eggshell (CTS-ES) particles as a biosorbent for removal of Cu(II) ions from aqueous media was considered in this research. For this purpose, chitosan was coated on eggshell (ES) particles through precipitation procedure. The coated particles were characterized by Fourier transform infrared, thermogravimetric analysis, and field emission scanning electron microscopy analysis. Kinetic studies showed that coating of chitosan on ES particles improved their Cu(II) adsorption capacity. The removal of Cu(II) ions by either ES or CTS-ES particles followed the pseudo-second-order kinetics, indicating that chemical sorption is the rate-limiting step for...
The impact of outcome framing and psychological distance of air pollution consequences on transportation mode choice
, Article Transportation Research Part D: Transport and Environment ; Volume 46 , 2016 , Pages 328-338 ; 13619209 (ISSN) ; Behrang, K ; Isaai, M. T ; Nejat, P ; Sharif University of Technology
Elsevier Ltd
Abstract
Recent years, air pollution phenomenon has become one of the crucial problems of Tehran, Iran. Due to main political and economic role of Tehran, population of this metropolis is high and increasing. Urban transportation of this highly populated city contributes more than 70% of air pollution problem in this city. Although a number of urban transport developments, policy measures and regulations have been employed, Tehran's air pollution has remained crucial thus far. Finding ways to encourage individuals to behave more sustainable can be considered as a substantial approach of tackling environmental problems such as air pollution, since it can be highly cost-effective and fast. This...
Developing air exchange rate models by evaluating vehicle in-cabin air pollutant exposures in a highway and tunnel setting: case study of Tehran, Iran
, Article Environmental Science and Pollution Research ; 2018 ; 09441344 (ISSN) ; Arhami, M ; Delavarrafiee, M ; Ketabchy, M ; Sharif University of Technology
Springer Verlag
2018
Abstract
The passengers inside vehicles could be exposed to high levels of air pollutants particularly while driving on highly polluted and congested traffic roadways. In order to study such exposure levels and its relation to the cabin ventilation condition, a monitoring campaign was conducted to measure the levels inside the three most common types of vehicles in Tehran, Iran (a highly air polluted megacity). In this regard, carbon monoxide (CO) and particulate matter (PM) were measured for various ventilation settings, window positions, and vehicle speeds while driving on the Resalat Highway and through the Resalat Tunnel. Results showed on average in-cabin exposure to particle number and PM10 for...
A variable turbulent Schmidt number formulation by numerical simulation of atmospheric plume dispersion
, Article International Journal of Modern Physics C ; Volume 29, Issue 4 , 2018 ; 01291831 (ISSN) ; Ebrahimi, M ; Qate, M ; Sharif University of Technology
World Scientific Publishing Co. Pte Ltd
2018
Abstract
Turbulent Schmidt number as an important parameter in computational fluid dynamic (CFD) simulations is strongly dependent on height, whereas it is mostly considered to be constant in the literature. This paper presents a new variable turbulent Schmidt number formulation which can calculate the relative concentrations (RCs) in neutral atmospheric conditions more accurately. To achieve this aim, RCs from continuous releases are calculated in different distances by the analytical Gaussian plume mode. CFD simulations are carried out for single stack dispersion on a flat terrain surface and an inverse procedure is then applied so that different turbulent Schmidt numbers are used as inputs to...
A numerical study of reactive pollutant dispersion in street canyons with green roofs
, Article Building Simulation ; Volume 11, Issue 1 , February , 2018 , Pages 125-138 ; 19963599 (ISSN) ; Afshin, H ; Farhanieh, B ; Sharif University of Technology
Tsinghua University Press
2018
Abstract
Roof greening is a new technique for improvement of outdoor thermal environment which influences air quality through its impacts on thermal and flow field. In order to examine effects of green roofs on reactive pollutant dispersion within urban street canyons, a computational fluid dynamics (CFD) model was employed which contained NO-NO2-O3 photochemistry and energy balance models. Simulations were performed for street canyons with different aspect ratios (H/W) of 0.5, 1.0, and 2.0 such that leaf area density (LAD) of green roofs changed. It was found that roof greening led distribution of pollutants to alter for H/W = 0.5 and 1.0 cases in such a manner that their averaged concentrations had...
A conflict resolution method for waste load reallocation in river systems
, Article International Journal of Environmental Science and Technology ; 2018 ; 17351472 (ISSN) ; Moridi, A ; Mirbagheri, A ; Abbaspour, M ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2018
Abstract
Various urban, industrial, and agricultural pollutions discharge more than river self-purification potential damages river ecosystem and increases water treatment costs. As different decision-makers and stakeholders are involved in the water quality management in river systems, a new bankruptcy form of the game theory is used to resolve the existing conflict of interests related to waste load allocation in downstream river. The river restoration potential can allocate to the conflicting parties with respect to their claims, by using bankruptcy solution methods. In this research, dischargeable pollution loads to Karun River are determined by pollution sources in various scenarios using...
Phosphorus transport in intensively managed watersheds
, Article Water Resources Research ; Volume 55, Issue 11 , 2019 , Pages 9148-9172 ; 00431397 (ISSN) ; Boardman, E ; Danesh Yazdi, M ; Finlay, J. C ; Hansen, A. T ; Baker, A. C ; Dalzell, B ; Sharif University of Technology]
Blackwell Publishing Ltd
2019
Abstract
Understanding controls of P movement through watersheds are essential for improved landscape management in intensively managed regions. Here, we analyze observational data from 104 gaged river sites and 176 nongaged river sites within agriculturally dominated watersheds of Minnesota, USA, to understand the role of landscape features, land use practices, climate variability, and biogeochemical processes in total, dissolved and particulate P dynamics at daily to annual scales. Our analyses demonstrate that factors mediating P concentration-discharge relationships varied greatly across watersheds and included near-channel sediment sources, lake and wetland interception, assimilation by algal P,...
An investigation into the effects of green space on air quality of an urban area using CFD modeling
, Article Urban Climate ; Volume 34 , December , 2020 ; Hosseini, V ; Sharif University of Technology
Elsevier B.V
2020
Abstract
Tehran, the capital of Iran, is one of the most polluted cities in the Middle East. However, there is no clear evidence of the effects of Tehran green spaces on reducing air pollution because there are still challenges to application of vegetation for improving air quality. The current study investigates the effects of a large volume of green space with 275 ha area in the vicinity of major highways on nearby air quality. Similar environments are often seen in many cities around the world. A computational fluid dynamics model containing aerodynamics and deposition effects of vegetation was used to simulate pollutant dispersion for eight wind directions and three different foliage densities....