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Biological Sludge Reduction in MBBR Process
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Moslehi Moslehabadi, Parivash (Supervisor)
Abstract
Laboratory experiments were carried out to investigate the effect of ultrasound waves on sludge reduction in MBBR bioreactor for industrial wastewater. The experiments were performed using two identical 20L MBBR bioreactor under same operational conditions. In MBBR with return sludge, sludge was collected from clarifier and after being sonicated, returned to the system by pump.
For determining optimum intensity and time duration of ultrasound, 0.3lit of MBBR sludge was sonicated with intensities of 20, 30, 60, 120, 150, 250 w/cm2 and time duration of 5, 10, 15, 20, 30 min. Afterward, these two parameters were optimized with Energy Efficiency Index. As the results shown, intensity of 120...
For determining optimum intensity and time duration of ultrasound, 0.3lit of MBBR sludge was sonicated with intensities of 20, 30, 60, 120, 150, 250 w/cm2 and time duration of 5, 10, 15, 20, 30 min. Afterward, these two parameters were optimized with Energy Efficiency Index. As the results shown, intensity of 120...
Design and Synthesis of Novel Coumarin Derivatives as Quorum Sensing Inhibitors & Performing Click Chemistry Involving Lysozyme Protein and a Novel Synthetic Fluorecent Compound
, M.Sc. Thesis Sharif University of Technology ; Kalhor, Hamid Reza (Supervisor)
Abstract
Quorum Sensing is a cell-to-cell communication pr°Cess depending on cell concentration. Communication among bacterial cells °Ccurs through small molecular signals called autoinducers. The consequences of quorum sensing include the activation of pathogenic properties and activation of the gene for biofilm formation. Biofilms are aggregations of bacteria that adhere to surfaces through extracellular polymeric substances. Bacteria in the biofilm phase are much more resistant to antimicrobial agents than their free-swimming counterparts (i.e. the bacteria in planktonic form). In this study, first a series of coumarin derivatives were synthesized; but due to low solubility of the synthesized...
Biological Removal of Nutrients in MBBR Reactors, Using Bardenpho Process Principle
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
Given that the most polluting industries in the country there. A suitable treatment system for degradation of these compounds is necessary unless unexpected effect on environment will occur.Moving Bed Biofilm Reactor (MBBR) was developed to adopt the best features of the activated sludge process as well as those of the biofilter processes. MBBR has biomass growth on carriers that move freely in the water volume of the reactor. High surface area of carriers make a good condition for biomass attached growth. This system has had good operation in the urban and some industrial wastewaters.In this study, four reactor volume of approximately 16 litr and 6, respectively, in the aerobic, anoxic...
Experimental Removal of Aromatic Hydrocarbons by Thermophilic Bacteria in a Fixed Bed Reactor
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Vossoughi, Manouchehr (Supervisor) ; Zeinali, Majid (Supervisor)
Abstract
According to the environmental lows and standards, wastewater of petroleum industries such as refineries and petrochemical that include many petroleum compounds like aromatic and aliphatic hydrocarbons, must be treated up to desirable limit, before entering the collecting network. Using microorganisms is one of the fundamental ways of biodegradation of these polluted compounds. Since phenolic compounds are the main components of raw petroleum, strains that are capable of tolerating phenol and usage of this poisonous hydrocarbon are specifically important. Therefore, in this study the potentiality of the indigenous thermophilic bacterium Nocardia otitidiscaviarum strain TSH1, for degradation...
Experimental Study on the Effect of Salinity on Biodegradation of Oil components (Furfural case study) in Moving Bed Biofilm Reactor (MBBR) System
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mahdi (Supervisor)
Abstract
Due to the increasing relationships, and expand the transportation of goods and fuel by ships and other factors may also cause the release of pollution into the sea, Oil and also its derivatives are the dangerous pollutants that threaten the health of the environment and may destroy the local ecosystem.One of its highly carcinogenic pollutants that even inhaled,is furfural. A new and efficient method for the filtration of toxic substances and hazardous wastewaters, using the moving bed biofilm reactor treatment that is MBBR system. Microorganisms present in the reactor, that was used in this project, from the microorganisms of industrial Behran Company. Removal of furfural from the harsh...
Oily wastewater treatment using membrane bioreactor
, Article International Journal of Global Warming ; Vol. 6, issue. 2-3 , 2014 , pp. 295-302 ; ISSN: 17582083 ; Alemzadeh, I ; Vossoughi, M ; Sharif University of Technology
Abstract
A novel implementation of a membrane bioreactor (MBR) has been studied in this paper. It is utilised as combination of rotating biological contractor (RBC) and an external membrane for oily wastewater treatment. The performance of MBR was compared with the standalone RBC. The RBC used in this investigation is the same one combined with the membrane to form the MBR. Wastewater biodegradability has been evaluated by two factors: chemical oxygen demand (COD) and total petroleum hydrocarbon (TPH). They are both compared together for different hydraulic retention times (HRTs) and petroleum pollution concentrations in RBC and MBR. The ratio of TPH to COD of molasses has been varied between 0.2 to...
Simultaneous biological organic matter and nutrient removal in an anaerobic/anoxic/oxic (A2O) moving bed biofilm reactor (MBBR) integrated system
, Article International Journal of Environmental Science and Technology ; Volume 14, Issue 2 , 2017 , Pages 291-304 ; 17351472 (ISSN) ; Seyedsalehi, M ; Safari, G. H ; Ebrahimi Arjestan, M ; Barzanouni, H ; Ghadimi, S ; Kamani, H ; Haratipour, P ; Sharif University of Technology
Center for Environmental and Energy Research and Studies
2017
Abstract
In the present study, the performance of three moving bed biofilm reactors (MBBRs) has been evaluated in series with anaerobic/anoxic/oxic (A2O) units for simultaneous removal of organic matter and nutrients (nitrogen and phosphorous) from a synthetic wastewater with characteristics similar to those of a typical municipal wastewater. Response surface methodology based on central composite design was used to investigate the effects of nitrate recycle ratio, hydraulic retention time (HRT), and influent chemical oxygen demand (COD) on the organic and nutrient removal and optimization process. The optimized values of influent COD, HRT, and R were 462 mg/L, 10 h, and 3.52, respectively. The...
Quantitative determination of linear alkylbenzene sulfonate (LAS) concentration and simultaneous power generation in a microbial fuel cell-based biosensor
, Article Journal of Cleaner Production ; Volume 294 , 2021 ; 09596526 (ISSN) ; Vahabzadeh, F ; Mardanpour, M. M ; Sharif University of Technology
Elsevier Ltd
2021
Abstract
Linear alkylbenzene sulfonate (LAS), one of the most widely used synthetic surfactants in laundry detergent industry, is considered a hazardous contaminant in wastewater. In the present study, a microbial fuel cell (MFC) based biosensor is developed to quantitively determine the LAS concentration in wastewater. To do so, the developed MFC is fed with LAS concentration of 60 mg l−1. Finally, a sustained biofilm is formed after almost 34 days and the highest open circuit potential of 425 mV is recorded. The maximum power and current densities of 75 mW m−3 and 663 mA m−3 are obtained, respectively; and the internal resistance of the MFC-based biosensor is calculated to be about 1 kΩ. After 98...
Multifunctional tetracycline-loaded silica-coated core-shell magnetic nanoparticles: antibacterial, antibiofilm, and cytotoxic activities
, Article ACS Applied Bio Materials ; Volume 5, Issue 4 , 2022 , Pages 1731-1743 ; 25766422 (ISSN) ; Eshrati Yeganeh, F ; Yousefi, M ; Baniyaghoob, S ; Farasati Far, B ; Akbarzadeh, I ; Bigham, A ; Ashrafizadeh, M ; Rabiee, N ; Makvandi, P ; Saeb, M. R ; Sharif University of Technology
American Chemical Society
2022
Abstract
In the current study, the physicochemical and biological properties of tetracycline-loaded core-shell nanoparticles (Tet/Ni0.5Co0.5Fe2O4/SiO2 and Tet/CoFe2O4/SiO2) were investigated. The antibacterial activity of nanoparticles alone and in combination with tetracycline was investigated against a number of Gram-positive and Gram-negative bacteria for determining minimum inhibitory concentration (MIC) values. The MIC of Tet/Ni0.5Co0.5Fe2O4/SiO2 nanoparticles turned out to be significantly higher than that of Tet/CoFe2O4/SiO2 nanoparticles. Furthermore, Tet/Ni0.5Co0.5Fe2O4/SiO2 nanoparticles exhibited potent antibiofilm activity against pathogenic bacteria compared to Tet/CoFe2O4/SiO2...
Studies on Hybrid Reactor Consisting of Sequential Aerobic-Anoxic Systems for Nitrogen Removal Process from Industrial WasteWater
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
In this study, the biological nitrogen removal process from a wastewater with high COD and TKN concentration was investigated in a hybrid reactor. In order to remove nitrogen completely with pre-denitrification process, both moving bed biofilm system and fixed bed biofilm system with pumice stone, were used in a single reactor (volume is 16 l). Moving bed biofilm and fixed bed biofilm systems were considered in sequence, as aerobic and anoxic parts of the reactor. 35% of the aerobic volume was occupied with plastic carriers and 70% of the anoxic volume was occupied with pumice stone with an average diameter of 30mm. Experiments were done in 7 runs, for total hydraulic retention times of 30,...
Nitrogen removal from high organic loading wastewater in modified Ludzack-Ettinger configuration MBBR system
, Article Water Science and Technology ; Volume 72, Issue 8 , October , 2015 , Pages 1274-1282 ; 02731223 (ISSN) ; Borghei, S. M ; Tahmasebian, S ; Andalibi, M. R ; Sharif University of Technology
IWA Publishing
2015
Abstract
A moving bed biofilm reactor with pre-denitrification configuration was fed with a synthetic wastewater containing high chemical oxygen demand (COD) and ammonia. By changing different variables including ammonium and COD loading, nitrification rate in the aerobic reactor and denitrification rate in the anoxic reactor were monitored. Changing the influent loading was achieved via adjusting the inlet COD (956-2,096 mg/L), inlet ammonium (183-438 mg/L), and hydraulic retention time of the aerobic reactor (8, 12, and 18 hours). The overall organic loading rate was in the range of 3.60-17.37 gCOD/m2·day, of which 18.5-91% was removed in the anoxic reactor depending on the operational conditions....
Niosome-encapsulated tobramycin reduced antibiotic resistance and enhanced antibacterial activity against multidrug-resistant clinical strains of Pseudomonas aeruginosa
, Article Journal of Biomedical Materials Research - Part A ; 2020 ; Abolhassani Targhi, A ; Shamsi, F ; Heidari, F ; Salehi Moghadam, Z ; Mirzaie, A ; Behdad, R ; Moghtaderi, M ; Akbarzadeh, I ; Sharif University of Technology
John Wiley and Sons Inc
2020
Abstract
In the current study, niosome-encapsulated tobramycin based on Span 60 and Tween 60 was synthesized and its biological efficacies including anti-bacterial, anti-efflux, and anti-biofilm activities were investigated against multidrug resistant (MDR) clinical strains of Pseudomonas aeruginosa. The niosomal formulations were characterized using scanning electron microscopy, transmission electron microscopy, and dynamic light scattering measurement. The encapsulation efficiency was found to be 69.54% ±; 0.67. The prepared niosomal formulations had a high storage stability to 60 days with small changes in size and drug entrapment, which indicates that it is a suitable candidate for pharmaceutical...
Enhancement of biological nitrogen removal performance using novel carriers based on the recycling of waste materials
, Article Water Research ; Volume 170 , March , 2020 ; Borghei, S. M ; Raie, M ; Sharif University of Technology
Elsevier Ltd
2020
Abstract
This study aims to enhance biological nitrogen removal performance by the innovative carbon-based carriers. The new carriers were produced based on recycling waste materials. In these carriers, the advantages of the hybrid system and physicochemical properties of activated carbon were integrated to promote microbial attachment. To verify the performance of the new carriers compared to the conventional moving carriers, the experiments were conducted in two parallel laboratory-scale sequencing batch reactors under various operating conditions. The analysis revealed that the specific surface area of the new carrier with a total pore volume of 0.0015cm3/gr was 10.9 times the specific surface...
The influence of carrier material on the dominance of polyphosphate-accumulating organism metabolism in the biofilm-based biological phosphorus removal process
, Article Chemical Engineering Journal ; Volume 450 , 2022 ; 13858947 (ISSN) ; Raie, M ; Borghei, S. M ; Appels, L ; Dewil, R ; Sharif University of Technology
Elsevier B.V
2022
Abstract
This study reveals that the type of carrier material affects the stoichiometry of the anaerobic conversion and the metabolism in cultures enriched with polyphosphate-accumulating organisms (PAOs) and helps increase the biological phosphorus removal performance. PAO-enriched biofilms were cultivated in two identical lab-scale sequencing batch reactors containing different carrier types: a typical moving bed bioreactor carrier (MBBR) and a novel carbon-based moving carrier type (CBMC) coated by activated carbon particles. The experiments were conducted at various influent PO43- concentrations (14, 17, 20 mg-PO43--P/L) and two aeration periods (220 and 460 min) under similar operating...
MBBR and MBR Reactor Configuration for Better Performance
, M.Sc. Thesis Sharif University of Technology ; Borgheei, Mahdi (Supervisor)
Abstract
Membrane bioreactors (MBRs) which are commonly understood as the combination of membrane filtration and biological treatment using activated sludge have several advantages, but membrane fouling reduces the membrane efficiency, permeability and lifetime. An alternative is replacing a moving bed biofilm reactor (MBBR) with the activated sludge system which may reduce the effect of membrane fouling. The sludge produced in MBBRs has poor settling characteristics, therefore, their efficiency is limited by the sedimentation tank performance and they require a larger settling surface. The combination of moving bed biofilm reactors and membrane bioreactors can compensate for the drawbacks of both of...
Improvement of Settleability and Sludge Characteristics in Moving Bed Biofilm Reactor (MBBR)
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mahdi (Supervisor)
Abstract
In the present study, effects of Post Aeration stage on moving bed biofilm reactor (MBBR) sludge and effluent quality was investigated by simulated wastewater. Reactors Volume were 3.2 and 5.9 Liter and their filling-fraction were 53% and 29%, respectively. All tests were done at 2.5 and 4.6 volume fraction, in which organic loading rates (OLR) were 2, 4, 6 g/L.d and Hydraulic retention times (HRT) were 3 and 6 hours. Increasing in HRT results in bioreactor efficiency improvement, the most efficiency values were found 81% and 84% for MBBR and MBBR-PA respectively at HRT of 6 hours and 53% filling-fraction. The greatest effect of post aeration on organic removal rate was obtained at HRT of 3...
Ethylene Glycol Removal from Wastewater by Biological Means
, M.Sc. Thesis Sharif University of Technology ; Borgheei, Mahdi (Supervisor)
Abstract
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...
Effect of Salinity on MLE Process Function
,
M.Sc. Thesis
Sharif University of Technology
;
Borghei, Mehdi
(Supervisor)
;
Kariminia Hamedani, Hamidreza
(Supervisor)
Abstract
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...
Ground Water Denitrification by Packed Bed Bioreactor With KMT Packing
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
In this study biological denitrification method by moving bed biofilm reactor is investigated. The main advantage of MBBR reactor is due to their capacity for high removal rates and low operational problems such as clogging. Two MBBRs in series with 3 liter volume each, were designed in experimental set up and used in this research. Nitrification reactor worked under aerobic conditions and denitrification reactor operated under anaerobic conditions. Methanol was used as carbon source in the reactors throughout the study. Fifty percent of each reactor volume was occupied with KMT1 packing. To finding the optimum nitrate loading rate, the concentration of ammonium and nitrate were changed from...
Optimization of Aeration & Dissolved Oxygen Concentration in Moving Bed Bio Reactors
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor)
Abstract
In this research the performance of the Moving Bed Biofilm Rector (MBBR) in different amounts of dissolved oxygen (DO) was investigated. Reactor with a useful volume of 15 liters was used in this study. In order to obtain optimum oxygen concentration, stayed at 6, 10 and 15 hours, and at different levels of dissolved oxygen in the range 0.5 -6 mg/lit, the amount of organic material was removed respectively. Also, in two different aeration intensity of 3.5 and 5.5 liters per minute at different values of e% (percentage of filling of media) the mass transfer coefficient values were obtained. When the aeration intensity increases from 3.5 to 5.5 liters per minute, and the percentage of 40%...