Sharif Digital Repository

With the growth of the population and the significant expansion of industries in the last century, many environmental problems have plagued developed and developing countries. One of these environmental problems is water pollution. Observing the effects of water pollution over time, sanitary and industrial wastewater treatment was proposed as a reliable solution. With technology development, wastewater treatment requirements have become stricter. The increase in energy consumption and wastewater treatment costs due to population growth and industrialization on the one hand and strict regulations, on the other hand, have forced those involved in this field to employ a variety of technical and... 

In this research performance of microbial fuel cells (MFCs) in continuous flow mode was studied. Different anodic chambers were tested and it was found that granular activated carbons (GACs) produced the highest power density (1228 mW/m3) in comparison with multiple anodes (731 mW/m3), single anode (294 mW/m3) and polymeric packings (40 mW/m3). It was also shown that in a plug-anodic chamber (PAC) the power output is reduced by reducing agitation of anodic volume. Adding more GACs to anodic chamber results in power increase, however by increasing occupied volume from 80% to 100% the power increase was negligible in result of cathodic reactions limitations. Feed flowrate was increased from... 

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  

The increasing demand for energy forced to production of oil as one of the main sources of energy. Along with the increase in oil production, the proportion of water produced with oil is increasing relative to the oil produced. On the other hand, environmental restrictions for the discharge of industrial effluents into the environment are becoming more and more stringent every day. Before discharging the effluent into the environment, petroleum must be removed. The complexity of these issues demonstrates the need to develop new technologies and improve the efficiency of existing technologies. Gas flotation are among the technologies adopted in the field that have been used throughout the... 

Osmotically assisted reverse osmosis (OARO) assimilates high efficiency due to non-thermal processes and accessing high salinity. This makes it suitable for high water recovery for the purpose of zero- and minimal liquid discharge desalination. Moreover, forward osmosis (FO) has low fouling efficiency which makes the operating costs of cleaning and replacement lower. This study aims at incorporating OARO and FO in a novel configuration with multiple inlet of the diluted draw solution to the regeneration section. Pinch analysis with simplifying assumptions was carried out for FO and OARO standalone stages. The results showed that pinch point in FO resides either on the beginning or at the end... 

Microbial desalination cells have been considered as one of the most promising technologies in water desalination and wastewater treatment. Due to slow biological processes, experimental approach toward these types of cells has always been a challenge. Consequently, modeling and simulation techniques are crucial to be developed in order to avoid wasting time and resources.In this study, a dynamic model for a microbial desalination cell consisting of three parts: anode, cathode and desalination section is proposed in which changes in microorganism concentration, acetate concentration as anode feed, oxygen concentration in cathode, pH changes and electrical potential drop in anode and cathode... 

In present work, we fabricated novel heterojunction magnetic composite and the goo visible-light-harvesting photocatalysts through integration of ZnFe2O4 and MIL-53 by facile solvothermal method. To understand physical and chemical structure prepared material and morphology of samples, The XRD,FTIR, FESEM, DRS and VSM analysis were carried out. The ZFO/M53Fe/vis-light system reveled 92.3% dye degradation which enhanced photo catalyst reactivity for the decolorization of Direct red 23 as anionic dye under irraditation of LED lamp through AOP environment friendly technology, which are significantly higher than those of pure ZFO and M53Fe semiconductors. more ever ,aforementioned composite... 

A Microbial fuel cell is a Bioreactor in which chemical bands are broken and their energy convert to electricity by bio-catalysts such as microorganisms and enzymes. Depletion of energy resources encouraged researchers to investigate microbial fuel cell as a power bio-resource. MFCs produce electricity or hydrogen without any net carbon emission. Nowadays, real applications of microbial fuel cells are limited because their power density level is very low (about 1000 mW/m2). Many research projects are running to modify MFCs operation and optimize its costs. The most important application of MFCs is electricity production, hydrogen production, waste water treatment and BOD5 biosensor. In this... 

A Microbial fuel cell is a Bioreactor in which chemical bands are broken and their energy convert to electricity by bio-catalysts such as microorganisms and enzymes.In this project, construction, substrate investigation and optimization of operational parameters were done. Microbial fuel cell as a waste water treatment method was considered in this project. As a result, different substrate were used in anode chamber of constructed microbial fuel cell. The most important ones were waste water containing ethylene glycol and crude oil.Consequently, lack of information about cathode operational parameters was led to optimum condition selection for pH, buffer concentration and ionic strength as... 

Today, membrane bioreactors (MBRs) process is one of the most important options in industrial and municipal wastewater treatment. In MBRs, membrane has an essential influence on their performance. In this study, polycarbonate was exploited as membrane to evaluate its performance in MBR since it has excellent mechanical properties. However, polycarbonate is brittle and breaks at low elongation at room temperature. Solution blending was utilized to improve polycarbonate’s properties. Blending membrane was characterized and assessed by scanning electron microscopy (SEM) and tensile strength. Polycarbonate solution blending with polyurehatne which has excellent toughness and flexibility enhance... 

In recent years membrane bioreactors (MBR) were widely used as an advanced process for industrial wastewater treatment. But fouling issue causes some restrictions in these systems. So for fouling reduction many researches were done.In this study for fouling improvement, blending of hydrophilic polymer (PAN) with main polymer PVDF was used. Blending membrane in phase inversion process with DMAC as solvent and water as non-solvent was made. For pore-forming in membranes, PVP as hydrophilic additive with three different composition was added and then for more enhancement of antifouling property of membrane, TiO2 nanoparticles with four different composition were added to polymeric... 

Industrial wastewater treatment has always been one of the significant human being problems for the years. In particular, sewage containing heavy metals that, if discharged into nature, would have irreversible effects on the ecosystem and human health. Due to their toxic nature, heavy metals will reduce the efficiency of wastewater treatment systems if they are not efficiently treated. Also, the removal of Nitrate from the wastewater, which is one of the most stable nitrogen oxides, has always been a serious human problem in the treatment of effluents due to their high solubility in water. The simultaneous presence of nitrate and heavy metals in the effluent will cause many problems in the... 

Nuclear energy is one of the most important sources of energy from the economical point of view and also in terms of cleanliness and safety. Hence, strategically, uranium is one of the most basic elements of the earth and nowadays, the importance of this element is more marked due to the nuclear industry developement. Therefore, uranium recovery from the wastes generated during nuclear fuel production in Isfahan’s uranium conversion plant- in which yellow cake is converted to uranium hexafluoride- is quite pivotal. In this experimental research, we have to remove Fluoride from waste after dissolution by several methods like precipitation. After that uranium is extracted from the sludge of... 

In the modern societies, wastewater treatment is essential in achieving high level of standard in environmental protection and disposal. Recently, many researches are performed to study the surfactants’ biological decomposition in wastewater treatment process. In this project, fixed bed aerobic reactors are used in order to remove surfactant from wastewater. Integrated fixed film activation sludge reactor (IFAS) is used to remove surfactants and organic matters. It also used to study the capability of micro organisms in organic load removal in fixed bed biofilm for biological treatment of industrial wastewater. Pumice stone were used as the support in the reactor. The pumice stone is a... 

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... 

Isfahan Zirconium Production Plant (ZPP) is one of the most important plants in the nuclear industry of Islamic Republic of Iran. The wastewater of this plant contains high values of Sodium, Chloride, Nitrate and low values of Calcium, Magnesium, Zinc and Zirconium ions. Its release has been banned by international and national law because of the dangers and toxicity of its ions for the environment and living organisms. Therefore, its refinement as a compensation of Iran’s water resources in agriculture and drinking water has received a major consideration. Among the common methods to removal of these ions, membrane process method is selected due to it's major benefits such as not producing... 

An increase of wastewater treatment plants and wastewater treatments methods have increased the importance of selection of best wastewater treatment alternative. This selection should not be merely based on the quality of effluent, but the whole factors (economic, environmental, technical and social factor) should be considered. Different methods for the assessment of wastewater treatment plants is used. For example, life cycle assessment is used for the evaluation of environmental impacts or cost-benefit analysis are used for economic analysis. But, for selection of the most sustainable technology whole factors should be evaluated together. Multi-criteria decision-making methods can be... 

Phenolic compounds are hazardous pollutants that are released into environment through wastewater discharges from variety of industries. Although good biodegradability has been reported at low concentrations, but at higher concentrations phenols are known to be antibacterial. In this study the Membrane Biological Reactor (MBR) with submerged hallow fiber membrane was operated at 25±2 ºC and pH=7.5±0.5 to treat a synthetic wastewater containing high phenol concentration (up to 5.9 g/l). Removal efficiency of phenol and COD were evaluated at four various “Hydraulic Retention Times” (HRT) of 24, 12, 8 and 4 hours. To test the tolerance of the bioreactor to phenol concentration various loading... 

Removing pollutants of water and, in general, wastewater treatment is one of the most important issues in the world. In this research, we synthesized a nanophotocatalyst based on znic-iron in the form of a magnetic core-shell Fe3O4@ZIF-8, and used to degrade the malachite green toxic color of wastewater. SEM, XRD and FT-IR analyzes have been taken and analyzed fore all three core, shell and core-shell composite catalysts.Due to the band gap of core-shell nanocomposite and the performance of the malachite green dye, a photocatalytic process under the visible light was obtained, which at an optimum amount of photocatalyst 0.003g, we reach 99.2% dye degradation at the 30ppm concentration. This... 

Increased photo catalytic activity of NiO and 〖Co〗_3 O_4 were obtained by Ni〖Co〗_2 O_4 synthesizing and supporting functionalized multiwall carbon nano-tubes via calcinations followed by hydrothermal precipitation. NiO, 〖Co〗_3 O_4 and Ni〖Co〗_2 O_4 were prepared in the same procedure exactly for the subsequent photo catalytic activity to be compared to Ni〖Co〗_2 O_4/MWCNT later on. The photo catalytic degradation of Reactive Red 120 dye as a deazo organic pollutant model was used for experimental photo catalytic performance analysis. The CCD method was applied for experimental designing, modeling, and optimizing the operational parameters of the photo catalytic degradation of RR120 using...