Loading...
Search for: batch-reactors
0.011 seconds

    Simultaneous ammonium and nitrate removal by a modified intermittently aerated sequencing batch reactor (SBR) with multiple filling events

    , Article Polish Journal of Chemical Technology ; Volume 18, Issue 3 , 2016 , Pages 72-80 ; 15098117 (ISSN) Hajsardar, M ; Borghei, S. M ; Hassani, A. H ; Takdastan, A ; Sharif University of Technology
    De Gruyter Open Ltd 
    Abstract
    Optimized methods for simultaneous removal of nitrate, nitrite and ammonium are important features of nutrient removal. Nitrogen removal efficiency in an intermittently aerated sequencing batch reactor (IA-SBR) with multiple filling events was studied. No external carbon source was added and three filling events were considered. Oxidationreduction potential (ORP) and pH curve at solids retention time (SRT) of 20 d were analyzed. Effects of three organic loading rates (OLR), 0.67, 1.0 and 1.5 kgCOD/m3d, and three nitrogen loading rates (NLR), 0.054, 0.1 and 0.15 kgN/m3d, on nitrogen removal were studied. Nitrate Apex in pH curve and Nitrate Knee in ORP profile indicated that the end of... 

    Molecular weight control of a batch suspension polymerization reactor

    , Article Iranian Polymer Journal (English Edition) ; Volume 11, Issue 6 , 2002 , Pages 403-411 ; 10261265 (ISSN) Shahrokhi, M ; Fanaei, M. A ; Sharif University of Technology
    2002
    Abstract
    This paper concerns molecular weight control of a batch polymerization reactor where suspension polymerization of methyl methacrylate(MMA) takes place. For this purpose, a cascade control structure with two control loops has been selected. The slave loop is used for temperature control using on-line temperature measurements, and the master loop controls the average molecular weights based on its estimated values. Two different control algorithms namely proportional-integral(PI) controller and globally linearizing controller (GLC) have been used for temperature control. An estimator, which has the structure of an extended Kalman filter (EKF), is used for estimating monomer conversion and... 

    State estimation in a batch suspension polymerization reactor

    , Article Iranian Polymer Journal (English Edition) ; Volume 10, Issue 3 , 2001 , Pages 173-187 ; 10261265 (ISSN) Shahrokhi, M ; Fanaei, M. A ; Sharif University of Technology
    2001
    Abstract
    This paper concerns non-linear state estimation in a batch polymerization reactor where suspension polymerization of methyl methacrylate takes place. A kinetic model proposed in the literature is selected and its validity has been verified through an experimental set-up. Based on this model monomer conversion and average molecular weights of the polymer are estimated using only one output measurement (reactor temperature). The performance of the estimator, which has the structure of an extended Kalman filter, is examined through simulation and experimental studies in the presence of different levels of parameter uncertainties. The effects of adding 'fictitious noise' and parameter state' to... 

    Effect of pH on aerobic granulation and treatment performance in sequencing batch reactors

    , Article Chemical Engineering and Technology ; Volume 38, Issue 5 , 2015 , Pages 851-858 ; 09307516 (ISSN) Rezasoltani, S ; Shayegan, J ; Jalali, S ; Sharif University of Technology
    Wiley-VCH Verlag  2015
    Abstract
    Two sequencing batch reactors were operated to investigate the effect of influent alkalinity and reactor pH on aerobic granulation. In the first reactor R1 with high influent alkalinity the pH was adjusted in the neutral range, and in the second reactor R2 with low alkalinity the pH was held within the acidic range. The R1-dominating species were bacteria and the appearance time of granules was three weeks after reactor start-up. On the other hand, the acidic environment of R2 provided favorable conditions for fungal growth, and rapid granule formation occurred within the first week of operation. The varying microbial structure of granules resulted in different reactor performance in terms... 

    Investigate Laboratory Production of Hydroxyurea

    , M.Sc. Thesis Sharif University of Technology Nejati, Poorya (Author) ; Bastani, Dariush (Supervisor) ; Seifkordi, Ali Akbar (Supervisor) ; Zegordi, Elahe (Co-Advisor)
    Abstract
    Hydroxyurea is an anticancer drug that is commonly used to treat chronic myeloid leukemia (white blood cell cancer in bone marrow), polycythemia vera (red blood cell cancer), sickle cell anemia, solid tumors, and in particular leukemia. In this research, in addition to analyzing all available methods for synthesis of hydroxyurea, the most economical method for synthesis of hydroxyurea which is Hantzsch method was chosen; then we synthesized hydroxyurea crystals using a precipitation or crystallization process. To do so, two hydroxylamine hydrochloride and potassium cyanate reactants have been used in the semi batch reactor. Since the reaction efficiency and purity of the synthesized... 

    Design and Construction of Aerobic Granulation Reactor in Order to Study the Effect of Cationic Polymer on Granular Formation

    , M.Sc. Thesis Sharif University of Technology Jalali Varnamkhasti, Sajjad (Author) ; Shaygan Salek, Jalaloddin (Supervisor)
    Abstract
    Despite many advantages of granular sludge in anaerobic reactors (e.g. UASB), over the past few years research attention had turned towards developing aerobic granular sludge. Although much research is carried out on the formation of aerobic granules, less work is reported on how to enhance granules characteristics such as increasing in granule size, concentration, durability and stability. The aims of this study are to investigate the effects of cationic polymer on granule formation and the way to improve granule characteristics. For this purpose two SBR reactors (0.15 m diameter and 1.8 m height, R1 and R2) were used by feeding synthetic wastewater (diluted molasses, COD ranging from 1400... 

    Determining the Optimal Kinetic Equation for the Transesterification Process in a Batch Reactor

    , M.Sc. Thesis Sharif University of Technology Belalzadeh Gavgani, Mahsa (Author) ; Ghotbi, Sirous (Supervisor) ; Larimi, Afsane Sadat (Supervisor)
    Abstract
    The aim of this project is to inventigate and synthesize CaO-based nanocatalysts with metal promoters of magnesium and lithium by wet impregnation and coprecipitation methods, which are used in the transesterification reaction of canola oil and methanol. Sections of thesis include review of before researches , synthesis of nanocatalysts, catalyst characterization tests,and investigation of reaction under optimal conditions. In wet impregnation method, nanocatalysts were made with 5% by weight of lithium-magnesium on the basis of CaO and with different weight percentages of these two elements. In the co-precipitation method , catalysts with a combined base of calcium oxide/magnesium oxide ... 

    Optimisation of SBR Systems in Treating Mono-Ethylene –Glycol Wastewaters

    , M.Sc. Thesis Sharif University of Technology Esmaili Hashemabadi, Zahra (Author) ; Borghei, Mehdi (Supervisor)
    Abstract
    In the present study , operation of a laboratory scale sequencing batch reactor (SBR) was evaluated to treatment of synthetic wastewaters containing ethylene glycol. Studies carried out with a plexiglass bioreactor whith effective volume of 18 lit.Aeration was supplied via two air diffusers that set at the bottom of the reactor. Synthestic wastewater containing ethylene glycol and molasses as carbon source and other nutrient such as diammonium hydrogen phosphate as phosphor source and urea as nitrogen source for biological activities was composed at the laboratory. To optimization of this reactor three parameters – aeration time, chemical oxygen demand and sudden change in arganic loading... 

    Treatability Study of Industrial Slaughterhouse Wastewater

    , M.Sc. Thesis Sharif University of Technology Khadem Masjedi, Siavash (Author) ; Shaygan Salek, Jalaloddin (Supervisor)
    Abstract
    Almost all of the animal slaughter is done in slaughterhouses. Environment concerns about slaughterhouse industries have been increased as increase in their production. In this study, a DAF+SBR system was used for treatment of industrial slaughterhouse wastewater and efficiency of this system was evaluated.In DAF, we used anionic polymer and PAC as coagulant. We reached best composition in 2 ppm of AP and 200 ppm of PAC. After that DAF system run in different pressures to estimate the best operational pressure & A/S. Best operational pressure and A/S is 4 bar and 0.038. After pretreatment, biological treatment by using SBR reactor was carried out. The results of the SBR reactor showed that... 

    Modeling and Predictive Control of Vinyl Acetate Polymerization in Semi-batch Reactor

    , M.Sc. Thesis Sharif University of Technology Najafi, Maysam (Author) ; Shahrokhi, Mohammad (Supervisor)
    Abstract
    Obtaining polymers with desired properties is very important from industrial point of view. Weight average molecular weight and polydispersity are two important polymer properties. It is also important to obtain a high monomer conversion. In this thesis production of polyvinyl acetate is considered. Under special conditions, the vinyl acetate reactor dynamics become oscillatory which makes the reactor control difficult. For obtaining polymer with desired properties, an objective function which includes weight average molecular weight, polydispersity and monomer conversion has been defined. Then by minimizing this objective function the optimal temperature trajectory is obtained. In this... 

    Degradation of Dye in Wastewater Using iron Based Porous Nanocatalyst in a Batch Reactor

    , M.Sc. Thesis Sharif University of Technology Mehdipour, Mohammad Hossein (Author) ; Ghotbi, Cyrus (Supervisor) ; Mahmoudi, Niaz Mohammad (Supervisor)
    Abstract
    consumption of which (especially azo dyes) have been increasing nowadays, causing the increase of textile wastewaters. Usually, these wastewaters contain an immense number of dyes, and if these dyes release in the environment especially in waters, they cause some problems, such as the change of watercolor as well as taste, and affect creatures' lives severely. Moreover, If the dyes are left untreated in aquatic ecosystems, they can remain in the environment for a very long time, resulting in harmful and irreversible effects. Azo dyes are classified as mono, di-, three, azo dyes due to their bonds. Because dyes are increasingly used, nowadays, different methods are developed for the treatment... 

    Biodiesel production from Spirulina microalgae feedstock using direct transesterification near supercritical methanol condition

    , Article Bioresource Technology ; Volume 239 , 2017 , Pages 378-386 ; 09608524 (ISSN) Mohamadzadeh Shirazi, H ; Karimi Sabet, J ; Ghotbi, C ; Sharif University of Technology
    Elsevier Ltd  2017
    Abstract
    Microalgae as a candidate for production of biodiesel, possesses a hard cell wall that prevents intracellular lipids leaving out from the cells. Direct or in situ supercritical transesterification has the potential for destruction of microalgae hard cell wall and conversion of extracted lipids to biodiesel that consequently reduces the total energy consumption. Response surface methodology combined with central composite design was applied to investigate process parameters including: Temperature, Time, Methanol-to-dry algae, Hexane-to-dry algae, and Moisture content. Thirty-two experiments were designed and performed in a batch reactor, and biodiesel efficiency between 0.44% and 99.32% was... 

    Performance Optimization of SBR Reactors Using Fluidized Media (Conversion of SBR to SMBBR)

    , M.Sc. Thesis Sharif University of Technology Safi Samghabadi, Farshad (Author) ; Borghei, Mehdi (Supervisor)
    Abstract
    In recent years, utilization of hybrid attached and suspended growth system for modification of conventional activated sludge systems has attracted a lot of attentions. Nowadays, with development of urban areas and also introducing new emerging contaminants and as a result an increase in the influent loading of wastewater treatment facilities, the importance of upgrading and retrofitting available facilities have been highlighted. Conversion of Sequencing Batch Reactors to Sequencing Batch Biofilm Reactors is a viable solution for overcoming these problems. Eventhough several researches have been conducted on removal of different contaminants through these systems, the information about the... 

    Optimization of the Pulp and Paper Mill Wastewater Treatment System from Recycling with the Aim of Reducing COD by Conducting a Laboratory Pilot Plant

    , M.Sc. Thesis Sharif University of Technology Yousefi, Farid (Author) ; Raie, Mohammad (Supervisor)
    Abstract
    Paper and cardboard waste pulping consume large volumes of water, so the discharge of this effluent without proper treatment can have far-reaching environmental consequences. The color and variable COD concentration of wastewater in this industry make treating this wastewater complicated. Therefore, this study aims to reduce the COD of the wastewater treatment plant of a pulp and paper mill under different laboratory conditions to achieve environmental standards in Iran.In this study, coagulation-flocculation and the Fenton process on the wastewater entering the treatment plant were investigated first. It was found that coagulation and flocculation by 750-1250 ppm of alum coagulant and ten... 

    Modeling the Removal of Phenol Dyes Using a Photocatalytic Reactor with SnO2/Fe3O4 Nanoparticles by Intelligent System

    , Article Journal of Dispersion Science and Technology ; Volume 36, Issue 4 , Apr , 2015 , Pages 540-548 ; 01932691 (ISSN) Sargolzaei, J ; Hedayati Moghaddam, A ; Nouri, A ; Shayegan, J ; Sharif University of Technology
    Taylor and Francis Inc  2015
    Abstract
    The objective of this study was to model the extent of improvement in the degradability of phenol dyes by SnO2/Fe3O4 nanoparticles using a photocatalytic reactor. The effect of operative parameters including catalyst concentration, initial dye concentration, stirring intensity, and UV radiation intensity on the photocatalytic batch reactor during removal of phenol red was investigated. Fractional factorial design and response surface methodology were used to design the experiment layout. The SnO2/Fe3O4 nanoparticles were synthesized using the core-shell method. The results of x-ray diffraction and transmission electron microscopy showed the successful synthesis of these nanoparticles. The... 

    Production of granulated-copper oxide nanoparticles for catalytic application

    , Article Journal of Materials Research ; Volume 25, Issue 10 , 2010 , Pages 2025-2034 ; 08842914 (ISSN) Hosseinpour, M ; Ahmadi, S. J ; Mousavand, T ; Outokesh, M ; Sharif University of Technology
    2010
    Abstract
    Ultra fine CuO nanoparticles In the range of 2 ± 0.2 nm were synthesized by the supercritical hiydrotliermal method in a batch reactor. Itwas demonstrated that elevating the pH of the Cu2+ precursor solution to around 6 (neutral condition) not only does not lead to excessive agglomeration of the particles, but also reduces particle size and in general promotes their nanoscale characteristics. Prepared nanoparticles were immobilized in the biopolymcric matrix of barium alginate and calcined at different temperatures resulting in micro spherical granules of high porosity and elevated mechanical strength. The fabricated samples were characterized using x-ray diffractometry (XRD), transmission... 

    Enhancement of biological nitrogen removal performance using novel carriers based on the recycling of waste materials

    , Article Water Research ; Volume 170 , March , 2020 Massoompour, A. R ; 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... 

    Photocatalytic decolorization of red dye in aqueous ZnO-TiO2 suspensions

    , Article International Conference on Smart Materials-Smart! Intelligent Materials and Nano Technology, (SmartMat-'08) and also the 2nd International Workshop on Functional Materials and Nanomaterials (IWOFM-2) ; Volume 55-57 , 2008 , Pages 577-580 ; 10226680 (ISSN); 9780878493562 (ISBN) Khameneh Asl, S ; Sadrnezhaad, K ; Kianpoor Rad, M ; Sharif University of Technology
    2008
    Abstract
    The photocatalytic decolorization of aqueous solutions of Direct Red 27 in the presence of various amounts of semiconductor powder suspensions has been investigated in a batch reactor with the use of artificial light sources. ZnO and TiO2 have been found the most active photocatalysts; the effect of catalyst loading and type on the reaction rate was optimized for maximum degradation. The results imply that 1:1 ratio is proper for the photocatalytic removal of Direct Red 27. In addition, the effects of particle size and surface area were examined in this photocatalytic process. The results showed that the decolorization efficiency increases with increase in surface area, and decrease in... 

    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) Massoompour, A. R ; 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... 

    Catalytic wet peroxide oxidation of phenol in a new two-impinging-jets reactor

    , Article Industrial and Engineering Chemistry Research ; Volume 48, Issue 23 , 2009 , Pages 10619-10626 ; 08885885 (ISSN) Dehkordi, A. M ; Ebrahimi, A. A ; Sharif University of Technology
    Abstract
    The catalytic wet peroxide oxidation (CWPO) of phenol with activated carbon (AC) as the catalyst has been successfully tested in a novel type of two-impinging-jets reactor (TIJR). The TIJR is characterized by a high-intensity reaction chamber, which is separated by a perforated plate from other parts of the reactor. The perforated plate was used as a filter to keep the catalyst particles within the reaction chamber. The influences of various operating and design parameters such as jet Reynolds number, feed flow rate, internozzle distance, and the jet diameter on the performance capability of the TIJR were investigated. As a result of the impinging process, turbulence, complex trajectory of...