Sustainable urban infrastructure
M.H. Mosstafavi; A.R. Karbassi; M. Pazoki
Abstract
BACKGROUND AND OBJECTIVES: The water field futurology is mostly focused on the water shortage and resulting political-security crises. However, the emphasis of this study is on the water pollution crisis. This study utilizes water decolorization and microbial decontamination as novel and low-risk methods ...
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BACKGROUND AND OBJECTIVES: The water field futurology is mostly focused on the water shortage and resulting political-security crises. However, the emphasis of this study is on the water pollution crisis. This study utilizes water decolorization and microbial decontamination as novel and low-risk methods in water and water resources sanitization with the preservation of the municipal environment approach. Modern oxidation methods for pre-treatment or aid-treatment have well-attained their place in the water and wastewater treatment process to reduce microbial and chemical contamination of water. Applying light, plasma, ozone, and Ultraviolet light is one of the modern and eco-friendly methods for water treatment and disinfection with growing usage.METHODS: In this research, various types of ozone and plasma generators, with the approach of energy consumption reduction, were manufactured for simultaneous decolorization and disinfecting of the water. All these devices consist of three main sections; frequency-increasing circuits, voltage-increasing transformers, and a reactor based on electrical discharge in gas. The simulation was performed using Orcad and PSPICE and Comsol softwares. After designing and simulation, a pilot of each of these three sections was made.FINDINGS: Both plasma and ozone reactors, which act as light tubes with a purple color spectrum were made and optimized for water treatment in the form of tubular tubes and flat cell for volume and surface radiation. Microbial testing of 8 water samples in terms of coliform in laboratory was confirmed by the Iran Environmental Organization mpn/100ml.RESULTS: After computer simulation, all three basic sections of an ozone generator device with a power consumption equal to a 30-watt lightbulb were made and optimized. By 5-minute injection of the ozone generated by this device into the water containing methylene blue as the color contamination index and Escherichia coli as the microbial contamination index, 99% of microbial decontamination was achieved, along with decolorization.CONCLUSION: Various types of plasma devices for decolorization and disinfecting water were made in this research. Due to the light-like nature of the plasma treatment and since the tested water sample was volumetric, and above all, due to the turbidity of the tested water sample, 30 minute of plasma treatment had no comparable effect to the ozonation method. Therefore, generating and injecting ozone was still the most effective method for simultaneous decolorization and microbial decontamination. The discoloration of water samples by ozonation with optimized devices was noticeable in the first minute.
Urban ecology and related environmental concerns
Gh. Ebraheim; A.R. Karbassi; N. Mehrdadi
Abstract
BACKGROUND AND OBJECTIVES: Rainwater in the city of Tehran is regarded as a freshwater source; however, because of highly polluted air conditions, the rainwater quality could be seriously affected. Therefore, the treatment of it could be an attractive topic for assessment. The purpose of the present ...
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BACKGROUND AND OBJECTIVES: Rainwater in the city of Tehran is regarded as a freshwater source; however, because of highly polluted air conditions, the rainwater quality could be seriously affected. Therefore, the treatment of it could be an attractive topic for assessment. The purpose of the present study was to treat Tehran rainwater by employing photoelectrocatalytic methods as one of the most powerful treatment methods. Also, this study aimed to find an easy laboratory procedure to create various redox environments and to assess a protocol for the release of metals.METHODS: The photoelectrocatalytic process was achieved by using a photocatalyst (Titanium dioxide) as the photoanode for the treatment of Tehran rainwater. Sodium ascorbate was used as a reducing modifier to assess the effect of various redox potentials on the performance of the photoelectrocatalytic process.FINDING: The positive redox potential, the 6 centimeter gap, and the sodium chloride concentration of o.65 g/L resulted in a considerable increase of the chemical oxygen demand, iron, manganese and lead removals. On the other hand, the negative redox potential, the 12 cm gap, and the sodium chloride concentration of o.65 g/L led to a noticeable increase in the removal of zinc. By employing the speciation and Pourbaix diagrams, the removal mechanisms of the PEC process were investigated. Chemical oxygen demand, iron and manganese by oxidation, lead, zinc and cadmium by precipitation were removed. Also, based on the cluster analysis, it was found that redox potential, dissolved oxygen and pH had a strong relationship.CONCLUSION: This work provided evidence that the redox potential could be regarded as a critical parameter helping to better estimate the risks associated with the polluted sites.
Human capital in urban management
H. A. Gafari; A.R. Karbassi; A. A. Rajabi
Abstract
This study is an attempt to monitor and investigate the main elements of social harms from political, economic, sociocultural, technological, environmental and legal perspectives in accordance with the factors of PESTEL. One of the findings of the present study indicates that Iran has taken several measures ...
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This study is an attempt to monitor and investigate the main elements of social harms from political, economic, sociocultural, technological, environmental and legal perspectives in accordance with the factors of PESTEL. One of the findings of the present study indicates that Iran has taken several measures in order to fight narcotics. In poverty and unemployment, it must be admitted that casting shadow of global economic situation on Iran's economy along with failure to implement Article 44 on the Constitution have led to the fact that a considerable section of the country’s economy has remained under direct government control. It seems that broadcasting performance has been weak from cultural perspective; this issue has caused satellite networks intrusion on the culture of people. No organization instructs young generation in life skills and how to prevent from divorce. This problem together with lack of life facilities has caused many marriages to end in divorce within the first year. Considering limited financial resources, the municipality and its affiliated organizations have had a quite good performance in organizing homeless people, but it is not sufficient. Donations contributing to susceptible classes of society are assessed absolutely positive and worthwhile. Street children are considered as an increasing harm in the world and Iran. If we do not reflect on some strategies in order to address this issue, it will be converted to a social crisis. Beggary has a significant manifestation in megacities as a social harm and challenge; it is mostly assumed to be a social dilemma rather than an individual problem. It can be really influential to educate people how to behave with beggars.
Urban health, safety and environment (HSE)
A.R. Karbassi; M. Shahpasand; A.A. Rajabi; H.A. Ghafari
Abstract
Today many of wide scope and famous organizations design and develop HSE models to achieve a more suitable HSE management system for their own purposes. To implement such models some requirements should be considered in line with defined goals and missions. The present study was carried out in order ...
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Today many of wide scope and famous organizations design and develop HSE models to achieve a more suitable HSE management system for their own purposes. To implement such models some requirements should be considered in line with defined goals and missions. The present study was carried out in order to achieve the HSE management system for children and adolescents in education and training centers. This study was conducted in two phases, namely identification and assessment/ documentation. The study was carried out in districts one, four, six, seven and eight of Tehran municipality during eighteen months. The employer was Tehran Shahr-e-salem Company (Healthy City) and the contractor was the faculty of environment, University of Tehran. As the final result of study, based on initial data and by holding brainstorming meetings, the final citizenship HSE model was constructed in five panels: Management responsibility and commitment, Infrastructures and resources management and documentation, Planning, HSE operations management and Monitoring, analysis and improvement. This model was designed by consideration of existing capacities and with the goal of being responsive to all stakeholders (service provider, recipients of services and others).
Urban transportation systems and traffic management
F. Salehi; A.R. Karbassi; M. Khashaypoor
Abstract
Bus rapid transit is an innovative, high capacity, lower cost public transit solution in metropolitan cities. Idea is to dedicate lanes for quick and efficient transport of passengers to their destinations. In the present investigation the environmental impact assessment of bus rapid transit in ...
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Bus rapid transit is an innovative, high capacity, lower cost public transit solution in metropolitan cities. Idea is to dedicate lanes for quick and efficient transport of passengers to their destinations. In the present investigation the environmental impact assessment of bus rapid transit in Tehran metropolitan city is brought out. For this purpose bus rapid transit Lane No. 10 is investigated. The bus rapid transit Lane No.10 is about 10 km in distance that moves up and down between Azadi and Simon Bolivar Squares. About 77500 passengers using 50 buses are transited per day in lane No. 10. These 50 buses cover a distance of 9600 km/day. The results of present study showed that about 6.5 million liters of fuel is saved annually. It should be pointed out that environmental costs are also reduced for about US$ 1.7 million/yr. The overall score of environmental impact assessment stands at +10 that is indicative of Lane No. 10 compatibility with the environmental considerations.