Treatment of Surfactant Wastewater by IFAS Bioreactors

, M.Sc. Thesis Sharif University of Technology Moradian, Amin (Author) ; Borgheei, Mahdi (Supervisor) ; Moslehi, Parivash (Supervisor)

Abstract

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...

, M.Sc. Thesis Sharif University of Technology Allah Yari, Mahdi (Author) ; Soltanieh, Mohammad (Supervisor) ; Moslehi Moslehabadi, Parivash (Supervisor)

Abstract

Air pollution caused by industrialization is the problem which adversely affects human life. Among air pollutants suspended particles, especially particles smaller than 10 microns (PM10), for their high concentration in air in large cities are the major index as air pollutant. Due to their small size, PM10 can penetrate into the aspiration organs causing harmful effects. The objective of this work is to develop an Artificial Neural Network (ANN) model for prediction of short-term concentration of PM10 in the city of Tehran. Complex mechanism of reactions, numerous types of pollutant materials produced from transportation and industrial activities, variety of sources, difficulties in data...

Feasibility Study on the Production of Biodiesel Using Domestic Wastes

, M.Sc. Thesis Sharif University of Technology Atapour, Mehdi (Author) ; Kariminia, Hamid Reza (Supervisor) ; Moslehi, Parivash (Supervisor)

Abstract

Biodiesel as an alternative fuel for fossil diesel has many benefits such as reducing regulated air pollutants emissions, reducing greenhouse gases emissions, being renewable, biodegradable and non-toxic. In this study, used frying oil was used as a low cost feedstock for biodiesel production by alkali-catalyzed transesterification. The used frying oil was originally a mixture of various oils obtained from vegetables that are native to Iran. The design of experiments was performed using a 5-level-5-factor central composite design coupled with response surface methodology in order to study the effect of factors on the yield of biodiesel and optimizing the reaction conditions. The factors...

Biological Sludge Reduction in MBBR Process

, M.Sc. Thesis Sharif University of Technology Tahmasebian Dehkordi, Sepehr (Author) ; 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...

Investigation of Petroleum Pollutant Removal in a Membrane Bioreactor

, M.Sc. Thesis Sharif University of Technology Rahmani Nezhad, Ali (Author) ; Kariminia, Hamid Reza (Supervisor) ; Moslehi Moslehabadi, Parivash (Supervisor)

Abstract

In this study, the performance of Convectional activated sludge reactor (CAS), moving bed biofilm reactor (MBBR) and coupled MBBR-membrane bioreactor (MBR) for diesel removal was investigated.
Hydrocarbon quantification was conducted based on a photometery method at 250 nm after extraction with n-hexane.
Experiments with MBBR was conducted in a batch mode using the sludge obtained from a municipal wastewater treatment plant. In order to adapt microorganisms with diesel as carbon sourse, diesel concentration was gradualy increased from 100 to 3400 ppm where diesel removal efficiency decreased from 62/1 to 26/6 %. However, after addition of diesel degrading bacteria (previously...

Heavy metal removal from water and wastewater using raw and modified diatomite

, Article International Journal of Engineering, Transactions B: Applications ; Volume 20, Issue 2 , 2007 , Pages 141-146 ; 1728-144X (ISSN) Moslehi, P ; Nahid, P ; Sharif University of Technology

Materials and Energy Research Center 2007

Abstract

Heavy metal removal from water and wastewater was investigated by using raw and modified diatomite from Iranian mines. Modification of diatomite was done by impregnating the diatomite surface with 0.35 g of manganese oxide in one gram of diatomite. This modified diatomite was named Mn-Diatomite. The surface area measurements for Mn-diatomite showed a 2.2 fold increase, hence higher removal capacity for the heavy metals. The results of the removal showed an increase in adsorption capacity which was for Pb2+ about 40 mg/g, for Ni 2+ about 34mg/g and for Cu2+ about 33mg/g. The filtration quality of diatomite was significantly enhanced with surface modification by manganese oxide

Design and Implementation of a CMOS Fractional-N Frequency Synthesizer for UHF RFID Readers

, M.Sc. Thesis Sharif University of Technology Moslehi Bajestan, Masoud (Author) ; Sharif Bakhtiar, Mehrdad (Supervisor)

Abstract

A 1.8-v 1.8-GHz fully integrated CMOS fractional-N frequency synthesizer is designed and tested for UHF RFID readers. The synthesizer employs a dual-loop architecture to realize a monolithic design with more optimal trade-off among phase noise, channel spacing, reference frequency and settling time compared to the conventional integer-N phase-locked-loop architecture. Due to the large self-interference and the backscatter scheme of the passive tags, reader synthesizer’s phase noise requirement is stringent to minimize the sensitivity degradation of the reader RX. A 1.8-GHz complementary VCO with noise filter has been used to achieve these tough specifications. Also, since a large KVCO can...

Two-machine flow shop scheduling to minimize the sum of maximum earliness and tardiness

, Article International Journal of Production Economics ; Volume 122, Issue 2 , 2009 , Pages 763-773 ; 09255273 (ISSN) Moslehi, G ; Mirzaee, M ; Vasei, M ; Modarres, M ; Azaron, A ; Sharif University of Technology

2009

Abstract

This paper presents optimal scheduling in a two-machine flow shop, in which the objective function is to minimize the sum of maximum earliness and tardiness (n/2/P/ETmax). Since this problem tries to minimize earliness and tardiness, the results can be useful for different production systems such as just in time (JIT). This objective function has already been considered for n jobs and m machines, but the proposed algorithms are not efficient to solve large scale problems. In this paper, neighborhood conditions are developed and the dominant set for any optimal solution is determined. The branch-and-bound (B&B) method is used to solve the problem and the proper upper and lower bounds are also...

Upgrading Activated Sludge Study System by Introducing Moving Carriers

, M.Sc. Thesis Sharif University of Technology Mofidian, Maryam (Author) ; Borghei, Mehdi (Supervisor) ; Mosleh Abadi, Moslehi (Co-Advisor)

Abstract

In this study, the use of a fixed bed of the Kaldnes commercial carrier in the activated sludge system has been investigated. In this way, at zero time, a submerged fixed bed of Kaldnes was placed into a completely mixed activated sludge reactor and its various parameters were investigated during the time. During the experiment, the fixed bed (Kaldnes carriers enclosed in a lace) with 20, 35 and 50 percentage of volumes were compared to regular activated sludge reactors (without any carriers). The studied parameters are COD, DO, MLSS, and P-PO43-. Input COD was changed at concentrations of 1200 and 400 mg/L, and the reactor hydraulic time was adjusted to 10 and 16 hours. It was observed that...