Sharif Digital Repository

This study focused on the investigation of bioleaching of heavy metals from incinerator ash using Thiobacillus thiooxidans. Eight factors were examined for their significance on bioleaching using a Placket-Burman factorial design. Four significant variables (pulp density, Initial pH, sulfur Concentration and inoculation amount) were selected for the optimization studies. The combined effect of these variables on metal bioleaching was studied using a central composite design. Second order polynomials were established to identify the relationship between the recovery percent of the metals and the four significant variables. The optimal values of the variables for maximum metals bioleaching... 

Underground water is one of major resources of drinking water in Iran and thus, its quality (in terms of absence of pollutants) is a matter of great importance. The main goal of this research was to investigate the pollution concentration in underground water and soil in two regions: Dasht-e-naz in Sari and the fields near Sarkhoun gas refinery. The second goal was to determine the source and measure the distribution of the pollutants (in case of presence) and determine potential risks caused by them. The first step was to perform experimental tests in the two regions. In Sari's Dasht-e-naz region, a number of wells were chosen for sampling according to the direction of underground water... 

With the increasing population and expanding urbanization and changing consumption patterns and relative prosperity increases, the amount of waste generated has increased significantly. So the municipal waste management as one of the challenges that lie ahead for municipal and state has become. Therefore, different approaches have been proposed to solve this problem. In the past government used landfill or incineration program for waste management. Given the risks to the environment and human health are two ways to create and large amount of biodegradable solid waste, composting seems to be good approach for waste management. With using the process on an industrial scale by municipalities,... 

Water-energy nexus approach is any water and energy interaction in a system to provide sustainable usage of resources. Quantitative model of interaction of water and energy in analyzing water-energy nexus is not comprehensive approach for solving all challenges facing this section. Qualitative analysis of water-energy nexus provides optimization and prioritization solutions in water and energy systems from other aspects. In present thesis two quantitative and qualitative aspect of water-energy nexus is considered. Initially, for quantitative modeling, interaction and relation of water and energy (watergy) with six principles to form WatErgy Reference System (WERS) was presented. The... 

The sudden increase in population growth rate in major cities and the recent changes in life style (consumerism) have resulted in a massive load of municipal solid waste. Managing this huge amount of waste imposes a heavy burden on municipalities’ shoulders. There are several options to Manage Solid waste, among them incineration and landfill are widely use in Managing municipal solid waste. Considering the fact that these two options are potentially hazardous to environment, high moisture content of municipal solid waste added, composting has become more trendy approach in last decades.Although composting is more environmentally friendly, it still needs the waste to be collected from all... 

Automation of the software development process is the software engineers' final goal, but with the current facilities and knowledge in software engineering, it is not possible to automatically generate the whole software. Usually all the software in a specific domain contain common behaviors, which by careful exploration of these common behaviors and automation of code generation in these sections, the cost and time of projects' execution can be reduced. According to Model Driven Development (MDD), the first step in software development is creating appropriate models. For creating models, metamodel is required; therefore, we need to create a specific motamodel for the chosen domain or use... 

With the growth of the urban population and the increase in private car ownership, negative implications of transportation, such as traffic congestion and environmental pollution has increased. A good solution to this problem is development of traffic infrastructures. However, it is not sufficient by itself and better management strategies for solving these problems are needed. One of the related approaches, is high occupancy toll lane. The main purpose of this study is modeling user’s mode choice behavior in the presence of high occupancy toll lane and pricing some highway lanes in Tehran. Another important purpose of this study is to find affective factors that have an influence on users... 

The cosmic ray astronomy was born in 1937 when Victor Hess flied with his balloon to the height of 17,500 feet. He found that the cosmic rays come from out of atmosphere. There are three fundamental questions from that time. The goal of all cosmic ray's experimental activities and related theories is finding out the answer of these questions. The first question is about the energy and composition spectrum of cosmic rays. The second one is finding the sources which can product the very high energy particles such as the protons with the energy of 1021eV found in some observatory such as AGASA and Haverah Park. The last question is the process of diffusion of cosmic rays in the galaxy. One of... 

Laboratory experiments were carried out to investigate the effect of influent alkalinity and reactor pH on microbial species, morphology and performance efficiency of aerobic granules. The experiments were conducted in two L sequencing batch reactors (R1-R2) with different influent alkalinity and pH medium. pH in R1 ,with high influent alkalinity, was in the range of 7-7.5 and pH in R2 was adjusted in 4.5-5.5. The experimental results demonstrated that the dominated microbial species and structure of granules were different in two rectors. Acidic environment of R2 provide favorable condition for fungal growth and granules formed within first week of operation. On the other hand in R1,... 

In this project, performance of anaerobic digestion of organic waste in liquid phase has been investigated in an experimental process. Thus, the objective of this study was to optimize the organic loading rates, temperature and mixing of anaerobic digestion to the treatment of municipal solid wastes. To achieve this, the pilot scale experiment was conducted in 70l, fully mixed reactor. The start-up process was established over a period of 2 months. Starting the digestion in two stages was done with two different feed stocks, in which the feed stock of the first stage was star and in the second stage vegetables were considered as the organic waste. Experiment was investigated in mesophilic... 

In this study the performance of the conventional activated sludge and the membrane bioreactor systems were investigated and their operations were compared. . A membrane bioreactor and a conventional activated sludge system which includes one aeration basin and one settling tank were designed and constructed. The feed was synthetic and the BOD:N:P ratio was 100:5:1. In order to starting the systems, the sludge supplied from the municipal wastewater treatment plant and inoculated. Then, the inoculated sludge was adapted to treat the starch wastewater with step by step increasing the feed COD. . The performance of two systems investigated in inlet COD=2500 mg/L and four hydraulic retention... 

In this thesis, an algorithm is developed based on Multi Criteria Decision Analysis (Analytical Hierarchy Process, TOPSIS) combination with Fuzzy logic, and then user-friendly software with a GUI was designed and introduced. By using this method, it becomes possible to compare processes based on their ratings and users desired importance, and finally determine the closest process to the user ideal choice  

Organic dye couldn’t be treated by conventional method (biological method) due to their durable structure. In recent years, graphene based adsorbent has become more popular; this is because of high specific surface area and presence of numerous functional group on its surface. Due to the widespread application of organic dye in different industry especially in textile industry, stability and toxicity nature of them, finding an appropriate and cost effective method in treatment of this pollutant is very important. In this study, preparing and characterization of 3-D gel magnetic graphene oxide/kappa carrageenan was conducted and its ability of dye adsorption was tested. For this purpose, at... 

The oilfields' wastewater, the water that is produced beside oil and is called ''Produced Water'', includes a large variety of pollutants. Heavy metals such as Lead, Manganese, Zinc and Barium and their compounds are some of the produced water's pollutants and because of their high stability they accumulate in life cycle. So a suitable and proper treatment is necessary. A combination of effectual and important parameters such as good adsorption, magnetic properties and low prices made Iron nanoparticles have a bright future in management of environmental pollutions. In this study Maghemite and Magnetite nanoparticles are used to remove heavy metals and effect of others factors such as pH,... 

Because of production of large volumes of Produces Water during oil exploration, it is necessary to purify this water for reuse or discharging to environment. Thus, finding a suitable method for removing contaminations seems necessary. In the present study, removal of soluble and dispersed organic contaminants from produced water by Dissolved Air Precipitation/ Solvent Sublation has been studied. Combination of floatation by dissolved air and extraction with solvent has been used for removal of organic compounds in order to study simultaneous effect of both methods on removal efficiency. Samples used in the experiments were tested in two groups: the first group was synthesized samples of... 

Water is used as a key material in different processes of chemical industries. Considering abundant demand of chemical industries for water, pollution that threats this valuable material and the fact that there is currently no proper substitute for water, an urgent necessity is felt for economic utilization of water in industrial processes and optimal use of water resources. A variety of methods have been developed for analysis of water consumption in industrial processes, amongst are Pinch methodology and Mathematical Programming approach. In this thesis a Petroleum Refinery has been preferred as a case study in which optimization of water consumption in the aforementioned petroleum... 

Biological treatment is an essential part of wastewater treatment. One of the major problems of the biological treatment systems is a solid separation. Filamentous bulking is a type of solid separation problem that settled sludge volume and the turbidity of the effluent will be increase in bulking condition. The presence of excessive Filamentous bacteria causes filamentous bulking. In this thesis, filamentous bulking were studied to understand this phenomena better and tried to control that with the different methods. This research was conducted in laboratory scale Sequencing Batch Reactor (SBR), conventional activated sludge and conventional activated sludge with anaerobic selector with...