Sharif Digital Repository

It is aimed in this study to numerically investigate the effect of contact angle on the heat transfer coefficient in oil-water two-phase flow. For this purpose, the finite element method (FEM) is used to solve the unsteady Navier-Stokes and energy equations. The level set method is also used to capture the interface between the phases. In the first part of the study, two-phase flow of the water and calibration oil is considered in a T-junction geometry at contact angles of 5°, 40°, and 75°. It is observed that the flow patterns formed in the microchannel depend on the initial flow condition which results in the hysteresis phenomenon. Investigating the effect of wall contact angle on the... 

Constructed wetlands are natural systems for wastewater treatment that Proper functionality of these systems to remove organic matter, pathogens, micro pollutants and etc., Are considered as environmental friendly systems. Proper capabilities of pollution removal and inexpensive cost of construction, commissioning and maintenance of these systems compared to engineering WWTPs in the world is leading to growing constructed wetlands. Due to the increasing use of artificial wetlands in the world for post treatment wastewater, because of right capabilities of this systems, and the absence of any natural wastewater treatment systems on Kish Island, this study investigates the possibility of... 

A major environmental challenge for wastewater treatment in Iran and other countries is the disposal of excess sludge produced during the biological process. This project has been developing and testing a technology that will help to overcome this challenge in Kish Island wastewater plant. Results demonstrate it can perform highly effective treatment of municipal wastewater while producing low levels of sludge.Applicationofvermifiltrationfor treatment of wastewater sludge using the Eiseniafetida earthworm species. The earthworms’ gut acted as a biofilter whereby there was reduction in the sewage wastewater’s solid and liquid organic and inorganic wastes through ingestion and expelling these... 

Garbage leachate which contains suspended and soluble pollutants is produced due to the decomposition of organic substances by microbial activities. Moreover, other sources of water such as surface runoff, rainfall, and groundwater – which in many cases may percolate through the garbage-, can intensify leachate production which in turn imposes considerable impacts on the main elements of the environment, such as water, soil, and air, and has health effects on human beings. Therefore, minimization of leachate production is an important issue in the solid waste management considering economic, social, cultural, and many other aspects. On Kish Island, despite the favorable climatological... 

Concrete is the second most structural material in the world. So attention and promotion of the concrete mix design with respect to variable issues and requirements, is very important. On the other hand, these days environment and its pollution has become very popular discussion. Waste-glass which is produced by human products is one of the environmental pollutants. In this thesis it replaces some aggregate in concrete and it can reduce the level of this material in the world. Also we study effects of silica-fume as cement replacement and properties enhancer in our concrete mix design and see how it can ... 

The present research is aimed at providing solutions for the implementation of the concept of lean production in manufacturing companies. As with increasing production, customer orientation, removal of waste and more arrangements, it can be used in the various equipment manufacturing industries (custom). It can be implemented in accordance with the conditions of each company, in order to help the production sector of the country and in order to develop appropriate strategies to improve performance, especially in the field of production, in line with the principles of pure production. Understanding the principles of pure production helps companies while familiarizing themselves with these... 

One of the novel methods of stabilization of nuclear waste is the use of vitrification technology. In order to stabilize high level wastes (HLLW) in glass, it is required that the elements are in their oxide form. Therefore, it is necessary to evaporate the waste and turn it into a solid form so that the elements can be converted into oxide form in the calcination furnace. Hence, one of the challenges of stabilization is the optimization of evaporation and calcination conditions. In this research, the parameters affecting evaporation were first investigated. Using laboratory measurements of application: temperature (110 to 180 °C), presence of nitric acid (0.5 to 4 mol/L), ratio of zirconium... 

Safety assessment of the final disposal of radioactive waste is crucial to ensure the waste isolation from the biosphere for long periods of time. There are various scenarios for the radionuclide transport from the disposal site to the environment, among which the ground water scenario is considered as the main scenario of the radionuclides migration. In this scenario, the transport parameters of the radionuclides are very important in the safety assessment of the final disposal of radioactive wastes. These parameters are determined using either dynamic or static methods, which usually the dynamic method leads to more realistic results. In the dynamic method, one of the two approaches of... 

The reaction of human societies with environmental limitations such as climate change and the prospect of limited mineral resources has led to the introduction of approaches such as circular economy. The implementation of circular economy requires the development of new assessment methods, technology development and planning. Even though in the economic theories of optimizing the extraction of exhaustible resources such as fossil fuel resources, methods are used to determine the optimal path of resource use, but the optimization of the return flow is less evaluated. In this research, the optimal material circulation model is developed based on material flow analysis and life cycle costing... 

Considering the operation of the current nuclear reactors and the country's policy to achieve 10,000 megawatts of nuclear power in the horizon of 1420, in the coming years we will face a huge amount of radioactive waste, the majority of which is waste with low and intermediate levels of radioactivity (LILW). A large percentage of the radioactive waste production in Bushehr power plant is concentrated waste with a low and intermediate level of radioactivity (about 70% by volume). Due to the commisining of phase 2 and 3 of Bushehr power plant in the coming years and the increase in the radioactive waste production, proper planning should be done for waste management in order to reduce the... 

Considering the operation of the current nuclear reactors and the country's policy to achieve 10,000 megawatts of nuclear power in the horizon of 1420, as well as the construction of research reactors, we will face a huge amount of radioactive waste in the coming years. Meanwhile, spent ion exchange resins constitute a large amount of low and intermediate level (LILW) solid radioactive waste produced from the nuclear industry. Therefore, appropriate precautionary measures should be taken for the immobilization and disposal of these radioactive wastes in order to ensure the sustainable development of the nuclear industry and the protection of the environment and human health. In this study,... 

Industrial symbiosis(IS) is a promising approach toward sustainable development goals. Among common modeling techniques, agent-based modeling holds a special place in IS simulation due to its bottom-up nature. However, the role of essential technologies in supply chain of IS has been poorly studied in the literature. In this work, first, an agent-base model is developed based on economic and environmental incentives of IS stakeholders employing optimization and non-cooperative game theory. Then, essential technologies in each potential symbiotic relation are integrated into the model to investigate their impact. The result suggests, to facilitate IS through environmental policy making, on... 

Due to the increase in population and the migration of people from rural to urban areas, the amount of municipal solid waste is increasing. Therefore, waste management is one of the most important social, economic, and even cultural issues in society now. In this research, one of the methods of waste management, i.e. energy production from waste based on municipal solid waste incinerators, will be investigated. Considering the sensitive environment of Mazandaran province, this province was chosen as the study area of the research. In the methodology of this research, after pre-processing the waste data of the case study, these data were determined as input conditions to the... 

Iran has many fossil fuels resources and today due to several reasons such as the environmental effects caused by burning these fuels, the depletion of fossil resources and energy security, the pattern of fuel production and consumption has changed.In recent years biofuels received the attention of researchers all over the world due to the sustainability of energy supply and their positive environmental effects. The agricultural wastes and Residues may be used to produce biofuels. Qazvin province, with its high potential of agriculture, can provide many sources of agricultural waste and residues for the production of biofuels. In this research, the aim is to optimize the biofuels supply... 

As nuclear energy continues to be used as a useful energy resource, waste management, especially management of high-level nuclear waste (HLW), will always be a major concern, as the future generations should not be deprived of the valuable benefits of this energy. Vitrification of liquid high-level radioactive waste (HLW) has received greater attention, worldwide, than any other high-level waste solidification process. The high solubility of HLW in borosilicate glass, the controllable temperature of this type of glass and its low leaching rate in repository environment, have introduced borosilicate glass as a suitable host for HLW immobilization. In this project, the immobilization of the... 

Nuclear waste management in Iran is the responsibility of the Nuclear Waste Company. The waste company is obliged to bury waste with a certain level of radioactivity, resulting from various processes of the nuclear fuel cycle or other processes such as research projects and medical centers, after the necessary measures, finally at the Anarak landfill site. To evaluate the safety of the site, it is necessary to study the parameters of radioactive nucleation in the soil. Humic substances from natural substances in the soil affect the transport of radioactive nuclei. In this project, to study the effects of the presence of humic acid, the soil of Anarak residue in three weight percent... 

In Iran, the Iranian Nuclear Waste Management Company (INWMC) is responsible for safe disposal of low-level radioactive waste which results from different processes of nuclear fuel cycle and other radioactive-related activities. The safety assessment program is essential to ensure safe isolation of radioactive waste from the biosphere for long periods of time. Usually, the ground water scenario is considered as the main scenario of radionuclides migration from repository to the biological environment. Thus, it is required to measure the transport parameters of radionuclides in the porous media (soil) around the disposal site. In this research, laboratory scale columns, filled with Nain... 

nowadays, due to population growth, unconventional use of water resources and on the other hand, climate change, limited renewable water resources, reduction of groundwater cavities, the need for water for agricultural use and energy production are increasing. Due to the fact that each cubic meter of dirty water pollutes 40 to 60 cubic meters of clean water and the entry of polluted effluent into the receiving sources of environmental degradation leads to a lot of wastewater treatment, water consumption management and The development of wastewater treatment processes is also becoming increasingly important. At present, wastewater treatment plants face the challenges of high energy... 

The growing amounts of generation of electronic wastes (e-waste) and their increasing environmental impacts require a special optimal waste management strategy. Many different methods have been developed to managing e-waste. To make the best choices according to the conditions of each system, having an adequate knowledge of all methods and comparing them is the most important point. This research aims to design a system for managing e-waste by selecting mobile phones as an example of electronic waste and find the optimal condition of the system to increase economic benefits and reduce environmental impact. Recycling and landfill are selected as the main methods in this project. Four lines... 

Increasing population growth and scarcity of fresh water resources have created the challenge of water supply, especially in the Mena region. Thus, many countries in the region have turned to innovation in the development of high-energy seawater desalination technologies. Utilizing the waste heat of refineries in the desalination industry can reduce costs and preserve the environment. In this article, effective ways to use the waste heat of other flue recovery steam of Bandar Abbas oil refinery are investigated. The integration of the heat recovery system consisting of recuperative heat exchangers and heat pipes with thermal desalination plants is investigated by multi-stage flash and...