Sharif Digital Repository

The membrane bioreactor (MBR) as an alternative method for simultaneous biodegradation and separation of oily water has received more attention, recently. Normally the MBR works at ambient temperature; therefore, the yield of biodegradation recalcitrant components is low. Increasing temperature improves the efficiency of degradation and reduces the amount of produced sludge. In this study the performance of an aerobic thermophilic and mesophilic membrane bioreactor (MBR) for treating oily wastewater has been investigated. In batch conditions (without applying the membrane), a comparison between COD removal in mesophilic and thermophilic conditions was done. In thermophilic conditions COD and... 

This study works on the novel researchment about produced waste water treatment in an annular single-chamber microbial fuel cell.This configuration has a spiral anode which increase available surface for microorganismes.In this study two main goals are followed;first Bio-eletricity production in a microbial fuell cell and second Bio-hydrogen production in a microbial electrolysis cell. In bio-electricity production effect of two parameters were considered;effect of light and substrate concentration .Two systems were used in this research;one of them was exposed to the light and another was out of reach of any light.Results show that darkness has better effect on the cell’s performance... 

In this research, MBBR was used to study petrochemical and gas refinery industry's low strength wastewater COD removal for reuse purposes. Reactor's feed was synthesized based on data analysis conducted by fourth wastewater treatment facility operating in phases 6,7 and 8. Inlet COD was 70 mg/L and this COD was provided by different portions of Mono ethylene glycol and Tri ethylene glycol. COD removal was studied under 1, 2 and 3 hours hydraulic retention time. Reactor's feed was provided with COD ratio of ( 〖COD〗_MEG/〖COD〗_total ) 65%, 60% and 50%. For the first time, hybrid combination of activated sludge system and MBBR was carried out and recycle stream was used in this system. The... 

The main objective of this project is the deposition of photo-catalysts on cement and concrete blocks with an emphasis on commercialization. We started with an extensive study of common methods introduced in previous literature, and conclude with a number of suggestions for industrialization. First, slurry and sol-gel deposition of the photo-catalysts on blocks of type 2 commercial cement which is one of the most used materials in construction of buildings and waste-water treatment plants has been examined to reach a method of sample formation. Due to the simplicity of common methods and low quality of formed samples (less than 5 percent aging efficiency), the obtained experience was used to... 

The dairy industry wastewater has high biological oxygen demand(BOD) and high chemical oxygen demand(COD). In this study, membrane bioreactor(MBR) was used for the treatment dairy industry wastewater. Since two diffuser,submerged membrane modul and intermittent suction method were adpted to system. In this study, the response surface method and experimental design were applied as an alternative to conventional methods for the optimization of the treatment. A central composite design, with 5 replicates at the center point were used to build a model for predicting and optimizing the treatment. Mathematical model equations were derived by computer simulation programming with Design Expert... 

Presence of heavy metals in industrial waste has always been a serious environmental problem. One of such metals in uranium that is used in important industries such as nuclear industry. Thus, it must be excluded from industrial waste efficiently. This research aimed to study effect of local strain of aspergillus niger in bioabsoprtion of uranium from industrial waste in which good absorption was reached and absorption of local strain was compared with that of control strain obtained from PTCC. Also, local strain was collected from uranium anomalies of Bandar Abbas Mining Site and was used to identify it with reference strains available at NCBI site using PCR and proliferation of part of... 

Vulnerability of water and sewage infrastructure in Kish Island survey versus natural and unnatural threats. It is important to know what to do when crisis or unpredicted event occurs in the Island. Decision makers and master managers of the Island, as the main custodians make suitable and effective reactions and decisions so that the impact of threats is reduced to minimum. According to the threats, there are short term and long term solutions. These solutions can be applied when the Island is encountered with crisis  

Azo dyes that are the most common dyes in textile industries, are toxic and stable complex compounds. Release of this dyes in environment disturb the ecosystem and endanger human health. So selection of an appropriate method for treatment of them is a sensitive work. photocatalytic degradation is one of the best promising methods because of its perfect mineralization, middle condition and lack of creating the secondary pollutant. In this research CuO/CNT nanocomposite was synthesized and used as a photocatalyst. The surface features of CuO/CNT were surveyed by using Fourier transform infrared(FTIR), X-ray diffraction (XRD) and Scanning electron microscopy (SEM). Photocatalytic efficiency of... 

Regarding the reduction of high qualified and accessible resources, the waste water treatments are accounted as one of the main challenges in environmental context. Surprisingly, with or without consideration of this issue can lead to play the crucial key in whether development or society retardation. With developing and being more sophisticated of waste water treatment technology and also rising the stringency of environmental constraint, approaching the optimum technology basis economics of scale is time consuming and complicated.Behind this concept, contribution of this study is twofold. The general approach of treatment is identified using AHP methodology in primary stage. After that, it... 

Removing nitrogen, as one of the most important contaminants of surface and ground water, needs to be considered. Since this material minimizes water quality and makes it useless. On the other hand, many industries as refineries have saline wastewater which their salinity removal is not economical by physical and chemical methods and is often impossible. Although biological treatment of saline wastewater has its problems, biological nitrification and denitrification are efficient and economical methods for nitrogen removal from industries saline wastewater. In this research, moving bed biofilm reactor (MBBR) adopted from Modified LUDZACK – ETTINGER (MLE) method has been used in order to... 

Tehran, the capital of Iran, like many megacities in the world is encountered with increasing freshwater demand and water resources limitation because of the rapid growth of population. In spite of the existence of neighboring water recourses; such as Karaj-Dam, Latian-Dam and Lar-Dam, and large usage of groundwater, the management of urban water demand is one of the biggest problems with this city. In this thesis, water reuse and wastewater recycling are considered as a sustainable solution for water supply and wastewater management of Tehran. A linear programming optimization model with the object of cost minimization is used to allocate water between users and resources, concerning the... 

In this thesis was investigated the effect of solid retention time (SRT), Hydraulic retention time (HRT), activated carbon and suspended carrier on styrene and ethylbenzene biological removal and also on membrane fouling. In addition to the typical analysis (COD, MLSS, MLVSS, and SVI), the flocculation ability, sludge particle size distribution (PSD), FTIR analysis, excitation-emission matrix (EEM) fluorescence spectroscopy, soluble microbial product (SMP), extracellular polymeric substance (EPS), microscopic observations, microbial activities, microorganism population, and filamentous bacteria are considered to determine sludge characteristics. This study was done in five sections: in the... 

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... 

Environmental issues and lack of drinking water had forced researchers to find some alternatives in order to wastewater treatment. Since dyes are used in a variety of industrial application such as textile, pharmaceutical, etc.; therefore, wastewater of these factories makes several environmental problems. Using catalysis under UV- irradiation (photocatalysis) is one of the cases that is used in wastewater treatment which the catalyst stimulated under UV- irradiation and this process degraded dyes. In this work, reactive red 198 degradation is investigated with MIL-53(Fe) and MIL-100(Fe) and in the literature section, the methods that was implemented by other researchers is studied.... 

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... 

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... 

If wastewater is not properly treated, then the environment and human health can be negatively impacted. These impacts can include harm to fish and wildlife populations, oxygen depletion and contamination of drinking water. In the typical wastewater treatment process, the goal of primary, secondary and tertiary effluent treatment is to reduce or remove organic matter, solids, nutrients, disease-causing organisms and other pollutants from the treated wastewater before it is discharged to a body of water. Biological methods for wastewater treatment are much preferable for being more economical and environmentally friendly. Biological treatment of wastewater using algal-bacterial culture... 

In this research, start-up, performance and stability of a A2O system (Anaerobic/ Anoxic/ Oxic) combined with a Moving Bed Bio Reactor (MBBR), using Kaldnes packings, have been investigated in treating synthetic dairy wastewater. Also the effect of influent Chemical Oxygen Demand (COD), Hydroulic Retention Time (HRT) and Ruturn Activated Sludge (RAS) ratio on removing pollutants such as COD, Total Nitrogen and Total Phosphorous have been studied. The experiments have been designed using ‘Design Of Experiments’ software, and at the end the results have been optimized based on desired terms. The performance and capability of the reactor in removing pollutants in 8, 12 and 16 hours of HRT,... 

Discharge of Raw wastewater or effluent of Treatment plants into the natural bodies of water, in the case of high nutrients may cause serious problems such as algae bloom which results in a reduction in concentration of dissolved oxygen. Among the nutrients, phosphorous is known as a limiting factor in growth and intensification (intensifier) of eutrophication. Therefore, elimination of phosphorus from wastewater prior to the discharge point is highly important. Phosphorus can be removed chemically as well as biologically. Chemical methods are known, efficient and reliable but Problems like operational and maintenance costs and chemical sludge production cause tendency to use biological... 

There are a lot of industry, including refineries with saline wastewater. Biological wastewater treatment saline pose particular problems and leads to plasmolysis microorganisms in the presence of salt. Remove salt from the wastewater before biological treatment by reverse osmosis or ion exchange and other methods are expensive and often impossible. Remove nutrients from wastewater before disposal and give up their saline for nature is essential. Because the these materials, especially nitrogen and phosphorus can degrade water quality and even make it unusable. So that by increasing the concentration of the algae production is also too much and cause eutrophication of water tanks are grown....