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M Farzadkia, R Rezaee Kalantari, S Jorfi, A.r Talaee, G.r Moussavi,
Volume 2, Issue 1 (16 2009)
Abstract

Background and Objectives : Propylene glycol is the main compound of anti-freezing chemicals. A significant amount of propylene glycol is released to the environment after application and contaminates the soil. The main objective of this study was to determine the biological removal of propylene glycol from wastewater and its degradation in soil by the isolated bacteria from activated sludge process.
Materials and Methods: In the present study, the sludge taken from the return flow in a local activated sludge treatment system was used as the initial seed. The performance of the bioreactor in treating the wastewater was evaluated at four different retention times of 18, 12, 6 and 4 h all with the inlet COD concentration of 1000 mg/L. This phase lasted around 4 months. Then, a part of the adapted microorganisms were transported from the bioreactor to the soil which was synthetically contaminated to the propylene glycol.
Results: The average of propylene glycol removal efficiency from the wastewater in detention times of 18, 12, 8 and 4 h in steady state conditions was 98.6%, 97.1%, 86.4% and 62.2% respectively. Also, the maximum degradation in soil was found to be 97.8%.
Conclusion: According to the results obtained from this study, it appears that propylene glycol is inherently well biodegradable and can be biodegraded in liquid phase and soil after a short period of adaptation.


S Jorfi, N Jaafarzadeh Haghighifard, R Rezaei Kalantary, Y Hashempur,
Volume 2, Issue 1 (16 2009)
Abstract

Backgrounds and Objectives: Direct biodegradation of landfill leachate is too difficult because of high concentrations of COD and NH3 and also the presence of toxic compounds. The main objective of this study was to application of Strurvite precipitation as a pretreatment stage, in order to remove inhibitors of biodegradation before the batch decant activated sludge process with addition of powdered activated carbon (PAC).
Materials and Methods: Strurvite precipitated leachate was introduced to a bench scale batch decant activated sludge reactor with hydraulic retention times of 6 and 12 hour. PAC was added to aeration tank directly at the rate of 3.5 g/L.
Results:TCOD, SCOD, NH3 and P removal efficiency with addition of PAC in HRT of 6 h were 90,87, 98.3 and 94 % respectively and 96, 95, 99.2 and 98.7 5 in HRT of 12 h.
Concusion:According to obtained data from this work, it can be concluded that Strurvite precipitation before batch decant activated sludge process and simultaneous addition of PAC is promising technology for leachate treatment and can meet effluent standards for discharge to the receiving waters.


F Rashid Ashmagh, R Rezaei Kalantary, M Farzadkia, A Joneidy Jafari, R Nabizadeh,
Volume 2, Issue 3 (25 2009)
Abstract

Backgrounds and Objectives: Polycyclic aromatic hydrocarbons (PAHs) are a group of hazardous pollutants which have carcinogenic and mutagenic properties and accumulated in environment by different actions, therefore treatment of them is important. Biological treatments are simple and cheep technologies. This technology was recommended as a cost- effective method for treatment of these pollutants. In order to investigate the trend of pollution reduction of petroleum hydrocarbons in bioremediation, the phenanthrene biodegradation&aposs model in contaminated soils was studied.
Materials and Methods: Firstly, PAHs capable degrading bacteria was isolated from petroleum contaminated soils and then their ability for biodegradation of phenanthrene was assessed in slurry phase. After that by using Acinetobacter which have the most potential of removing phenanthrene from soil, the biodegradation model was investigated in bench scale.
Results: Phenantherene removal efficiency was obtained 99.4% for 100 mg/kg and 96 % for 500 mg/kg concentrations in 33 and 60 days biodegradation period respectively. Phenantherene reduction rate varied from 2.99 to 8.86 and 1.4 to 11.09 mg/kg/day for 100 and 500 mg/kg concentrations, respectively.
Conclusion: Rate of phenantherene removal is depended on primary concentration of contamination and by increasing of primary concentration, phenantherene removal rate was increased. Also removal efficiency followed zero and first order kinetic model with good correlation.


N Jaafarzadeh Haghighi Fard, S Salamat, Z Rezvani, M.a Behrooz,
Volume 2, Issue 3 (25 2009)
Abstract

Backgrounds and Objectives: As industries are developed, human uses of the energy in the huge scale and release the loss  energy in the form of electromagnetic radiation such as infrared into the environment, that it could affect on the man health. According to the available standards, if the IR-A could be controlled and consequently health of workers could be provided, it would reduce the total industrial expenses.
Materials and Methods: To control this radiation, it is necessary to measure it and compare the results with the available standards. Hence, in this study, we try to  measure this radiation in a unit of industy. For this porpuse the unit of steel company that settled in southeast of ahvaz is selected.
Results: The determinations were done every month during one year in all selected units. These results are compared with the available standards, and finally the differences are statistically evaluated by some suitable statistical methods. For measuring the dispersal of ray in the diffrent height. bat hard data compared with ACGIH standard and SPSS software is used for changing Radiation.
Conclusion:  The  average amount of IR-A  at  this  industrial  unit  is  1.18 mW/cm2  which  is more than the standard value in such industries ,and based on our fouding the natural solar source of this radiation increases such effects in out-door work places.


N Jaafarzadeh Haghighi Fard, A.r Talaiekhozani, M.r Talaiekhozani, S Jorfi,
Volume 2, Issue 4 (9 2010)
Abstract

Backgrounds and Objectives:Propylene glycol is applied in many industries as raw material and can be released to the environment through wastewater of such industries. The biological treatment of solutions containing high concentration of propylene glycol is difficult and some problems can be observed during this process. The main objective of this study was the investigation of electrochemical degradation of propylene glycol and the parameters influencing on improving removal efficiency.
Materials and Methods: In this study the degradation of propylene glycol was made by passing an electrical current though the synthetic wastewater containing propylene glycol. In order to investigate this process several types of electrode with applied voltage ranging between 5 to 50 V was used. Due to the effect of NaCl concentration on removal efficiency which was mentioned in the literature, the experiment was performed for different NaCl concentrations.
Results: In optimum condition, the maximum removal efficiency of propylene glycol (based onCOD) was obtained equal to 90%. The results showed that rising applied voltage, NaCl concentrationand retention time increase the removal efficiency. The optimum retention time was obtained equalto 50 min. The maximum removal was obtained when aluminum electrode was used. It can beattributed to the production of coagulant material such as Al+3 during this process.
Conclusion: The results revealed that this process can be useful for treating the industrial wastewatercontaining propylene glycol.


M.a Zazouli, E. Ghahramani, M. Ghorbanian Alahabad, A. Nikouie, M. Hashemi,
Volume 3, Issue 1 (3 2010)
Abstract

Backgrounds and Objectives: One of environmental outcomes in industrial towns is developing environmental pollution such as production of industrial wastewaters. These industrial wastewaters should be appropriately treated before entering to receiving waters. However we can't solve environmental anxieties by establishing of wastewater treatment plants alone but permanent and regular assessment of these treatment plants performance is necessary for achieving environmental standards. Thus, this research has been done in order to investigation of activated sludge performance in wastewater treatment of Agghala industrial town in Golestan province.
Materials and Methods: This cross-sectional study implemented in sewage treatment plant laboratory of Agghala industrial town in Golestan within 12 months at 2007. Chemical Oxygen Demand (COD) parameter determined twice in week, But Biochemical Oxygen Demand (BOD) test accomplished weekly. pH measured by pH meter daily. Experiment of total suspended solids (TSS) and total dissolved solids (TDS) carried out every 10 days. All tests accomplished according to standard method for water and wastewater examination (2005). Then data analyzed using excel 2007.
Results: The average of BOD, COD and TSS in influent was 11196.17, 1854.58, 1232.25 mg/L respectively.Maximum influent organic loading rate was related to Shahrivar andMehr months. The total average of removal efficiency for BOD, COD and TSS was calculated 99.66, 98.2, and 97.6% respectively.
Conclusion:Quality of this treatment plant effluent was according to effluent disposal standards all over year. In sum, efficiency of this treatment plant (activated sludge system) was very good ininfluent pollutant removing. However occasionally effluent was not adapted with environmental standards but these deficiencies is solvable by accurate management and supervision on flow rate and influent organic loading rate easily.


M Malakootian, N Jafarzadeh Haghighi Fard, M Ahmadian, M Loloei,
Volume 3, Issue 2 (6 2010)
Abstract

Backgrounds and Objectives: Untreated leachate is discharging into the environment in the many countries of worldwide. Leachate treatment methods have not been unified so far due to variable composition of leachate. Moreover, the uncontrolled management of leachate, cause many environmental dissociates. The aims of this study apply the Fenton process to decrease the pollutants of Kerman leachate.
Materials and Methods: Rawleachatewas obtained fromcompactor vehicles used for the collection of Kerman city solid waste, before final disposal. In order to removal of biodegradable organic compounds, a rector was built based on characteristics of landfill Kerman city and raw leachate underwent anaerobic treatment in this pilot. In the next stage, treated leachate in the pilot, was affected by Fenton process. The optimized parameters in Fenton process including pH, reaction time and dosage of H2O2 and Fe2+ were also studied.
Results: The results showed that TSS, BOD5 and COD decrease to 62*, 96*and 89*, respectively, after 60 days treatment in the pilot. BOD5/COD ratio also decreased from 0.6 to 0.2 in anaerobic treated leachate. In optimum condition (pH=3, reaction time=75 min, Fe2+=1400 mg/L and H2O2 = 2500 mg/L) maximum COD removal was 78 * by Fenton process. BOD5/COD ratio increased from 0.2 to 0.51 which showed an increase in biodegradability of leachate as a result of Fenton process.
Conclusion: anaerobic biologically treatment followed by Fenton processes could be assumed as an efficient process that could improved the leachate quality. Biological treatment to reduce leachate pollution alone was not enough. The most important Fenton process advantage is reduction of refractory and toxic leachate compounds and increasing leachate.s biodegradability.


A.r. Talaie Khozani, N Jafarzadeh Haghighi Fard, M.r Talaie Khozani, M. Beheshti,
Volume 3, Issue 2 (6 2010)
Abstract

Backgrounds and Objectives: Oil pollution can be generated as a result of spillage, leakage, discharge, exploration, production, refining, transport and storage of crude oil and fuels in the environment. Consequently, many researchers have developed and studied the chemical, physical and biological methods to degrade crude oil. Among them, the biological treatments are the most interesting as they are simple and economical methods. The aim of this study was to determine biokinetic coefficients of crude oil degradation by pseudomonas aerogenusa. This microorganism was isolated in our previous work.
Materials and Methods: In this study the bio-kinetic coefficients of crude oil biodegradation were evaluated. Pseudomonas aerogenusa bacteria which had been isolated from the soil sample taken from a gas station in our previous work were used in this study. This microorganism was cultured in the liquid medium containing crude oil as sole carbon source. Finally with determining the amount of microorganisms and crude oil concentration during biodegradation process, the bio-kinetic coefficients based on modified Monod equation were calculated.
Results: bio-kinetic coefficients obtained from laboratory studies are vital factors in industrial applications. As a result, the bio-kinetic study was performed to find bio-kinetic coefficients for biodegradation of crude oil using the isolated bacteria. The results showed that ,Y, k and were equal 0.107 , 0.882 , 9.39 and 169.3 respectively.
Coculusion:Our results showed that pseudomonas aerogenusa is usable for treatment of oily wastewaters in the full scale facility. Results of this study indicated bio kinetics confections.


P Atabakhsh, M.m Amin, H Mortazavi, M Yaran, A Akhavan Sepahi, A Nouhi, M Jalali,
Volume 3, Issue 3 (4 2010)
Abstract

Backgrounds and Objectives:Total and Fecal coliforms (TC and FC), heterotrophic plate count (HPC), were counted by microbiological method and E.coli O157:H7 were detected through immunological and Real time PCRmethods inwater intake and all of units of Isfahanwater treatment plant (IWTP).
Materials and Methods: The microbial profile including TC, FC, and HPC, were monitored and turbidity and total organic carbon were analyzed in 8 locations of water intake, and unit operation and processes of IWTP, including, inlet, sedimentation, ozonation, and filtration and finished water. Immunological method through anti-serum kits and molecular method of RT-PCR were used to detect E.coli O157:H7 in the 8 locations and also the sludge of the sedimentation basin and filters backwash water of IWTP.
Results: Survival of E.coli O157:H7 in sludge sample of sedimentation basin was indicated by formation of agglutination particles in immunological method and through indicator probes in the RT-PCR method. However, E.coli O157:H7 was not detected in water samples of other units of IWTP. The removal percent of TC, FC, and HPC were: 59.5, 49, and 54.8 % in sedimentation basin 66, 45.8, and 57 % in ozonation: 98.8, 98, and 78.8 in the filtration and 96, 100, 91% in disinfection, respectively.
Conclusion: This study approved the existence of the pathogenic coliform, E.coli O157:H7 in the
sludge of sedimentation basin. Absent of E.coli O157:H7 in the finished water indicates that the existing units of IWTP could eliminate these pathogenic bacteria, before reaching the final units of the plant, including the filters and disinfection.


E Kalantar, A Maleki, M Khosravi, S Mahmodi,
Volume 3, Issue 3 (4 2010)
Abstract

BackgroundsAandObjectives: Pseudomonas aeruginosa and Staphylococcus aureus are important pathogens that producewidespread infections. Purpose of this studywas to evaluate the antimicrobial effect of ultrasonic irradiation (US) alone and in combination with antibiotic on antibiotic resistance Pseudomonas aeruginosa and Staphylococcus aureus.
Materials and Methods: In this study ultrasonic irradiation (US) in a laboratory-scale batch sonoreactor with low frequency (42 kHz) plate type transducer at 170W of acoustic power was used. The Water samples, were taken from different wards of the 3 teaching hospitals which were affiliated to the Kurdistan University of Medical Sciences to isolate Pseudomonas aeruginosa and Staphylococcus aureus and also to determine their antimicrobial susceptibility pattern.
Results:Our results showed that Pseudomonas aeruginosa and Staphylococcus aureus were affected by the ultrasound and the bactericidal effect increased with time.
Conclusion: It was found that P. aeruginosa was more susceptible to the ultrasonic treatment than S. aureus. The combination of US with an antibiotic (amoxicillin) enhanced killing of both bacteria over the use of US alone. There were no differences in resistance to ultrasound between isolated strains and standard strains from persian type culture collection.


P Bahmani, R Rezaei Kalantary, M Gholami, A Jonidi Jafari, Z Javadi,
Volume 3, Issue 4 (8 2011)
Abstract

Backgrounds and Objectives: Reactive dyestuff has potential of toxicity, carcinogenesis and mutagenesis for mammals and aquatic organisms. The current physical and chemical methods such as adsorption, coagulation, precipitation, filtration and ... can been used for removing of dyestuff. Biological treatment which is effective and economic for decontamination of dyestuff wastewaters was preferred because of limitation and difficulty of physicochemical methods. In order to investigate the trend of pollution reduction of color compounds, ability of Remazol Black-B dyestuff removal from aqueous medium by bacterial consortium under anoxic conditions was studied.
Materials and Methods: The mix culture of bacteria from textile industries activated sludge was enriched in luria broth medium containing RB-B dyestuff as a carbon source. Then biodegradation was assessed in 4 batch reactors. Microbial population of bacterial and decolorization quantities of samples were detected by MPN and UV-Vis spectrophotometer.
Results: Decolorization efficiency by the bacterial consortium was obtained more than 99% for 50 and 250 mg/L concentrations in 72 and 144 h (3 and 6 days) respectively, while for the initial concentration of 500 mg/L was 98.1in 240 h (10 days) of biodegradation period. Dyestuff reduction rate after completed removal was about 0.69, 1.74,2 mg/L/h for initial concentration of 50, 250, 500 mg/L respectively.
Conclusion: Results showed that Alcaligenes denitrificans and Alcaligenes xylosoxidans bacteria
which were isolated from activated sludge have good potential of RB-B dyestuff removal and this removal is depending on primary concentration of dye. Removal efficiency increased as primary concentration went up.


M Malakootian, K Yaghmaeian, M Meserghani, A.h Mahvi, M Danesh Pajouh,
Volume 4, Issue 1 (24 2011)
Abstract

Background and Objectives: Heavy metal pollution has always been a major cause contamination of environment and considered as a major concern for food health. Rice is the most popular food among Iranians and presence of heavy metals in trace level in rice has received special attention because they are directly related to health.The aim of this research was to investigate the concentration of Pb, Cd, Cr, Ni in rice prevalent in the market of Iran.
Materials and Methods: 20 of the most widely consumed brands of Iranian rice were purchased from local market in Iran. 3 samples of each brand were collected and certain volumes of each sample were digested with acid. Heavy metal contents in the digested samples were determined by atomic absorption spectrometry.
Results :The results showed that mean concentration Pb , Cr , Ni in rice samples respectively was 0.387 , 0.683, 0.019 ( mg/kg )
Conclusion: Notably the Ni and Cr content in the rice samples was found to be below the food sanitary standards in India rice . In the other hand 50% samples content Pb was found to be upper the food sanitary (Pb: 0.3 mg/kg). The result indicated that weekly intake of heavy metal by rice was below the provisional tolerable weekly intake recommended by WHO/FAO. However, risk assessments needs considerable attention and better prevention this low pollution.


S Jorfi, R Rezaei Kalantary, A Mohseni Bandpi, N Jaafarzadeh Haghighifard, A Esrafili, L Alaei,
Volume 4, Issue 1 (24 2011)
Abstract

Background and Objectives: Fluoride is widely used in industries such as manufacture of semiconductors, power plants, glass production etc and release to the environment via their effluents. The purpose of this sturdy was to compare the efficiency of low price adsorbents in fluoride removal from water.
Materials and Methods: The optimum values of pH, contact time and adsorbent dosage were determined and different concentrations of fluoride were experimented in lab scale conditions for bagasse, modified bagasse and chitosan. Then Langmuir and Freundlich coefficient were determined based on optimum conditions.
Results: The pH value of 7, contact time of 60 min and adsorbent dosage of 2 g/L were determined as optimum conditions for all three adsorbents. The most fluoride removal efficiency of 91% was obtained for modified bagasse in optimum conditions.
Conclusion: Based on data obtained in this study, it can be concluded that adsorption by modified bagasse is an efficient and reliable method for fluoride removal from liquid solutions.


A Mirzaei, A Takdastan, N Alavi Bakhtiarvand,
Volume 4, Issue 3 (1 2011)
Abstract

Backgrounds and Objectives: Selection of  proper coagulants for turbidity removal and determination of effective methods to reduce coagulants dose and related costs in water treatment plants is of critical importance. The present study investigates the effect of returned sludge on improving the performance of poly-aluminum chloride (PAC) in turbidity, coliform bacteria, heterotrophic bacteria removal from drinking water during rapid mixing phase.
Materials and Methods: In order to determine the optimal returned sludge volume injected during rapid mixing with PAC for turbidity, total coliform and hetrophic bacteria, experiments were conducted based on variables such as injected silt volume (from 0 - 125 ml), and varying turbidities from 58 - 112 NTU. At the end of each JAR experiments, remaining turbidity , microbial parameters of samples were measured . Coagulant efficiency in turbidity removal and microbial parameters were determined by Covariance, Duncan analyses and graphs were drawn by MS Excel . The results statistically showed significant among variables (P<0.05).
Results: The results showed that the maximum turbidity removal efficiency of 98.92 at 30 ppm was 10 ml while the maximum turbidity removal efficiency of 98.31 at 10 ppm was 4 ml. The maximum total coliform removal efficiency  of 95.68 obtained for 10 ppm in 10 cc injected sludge volume.
Conclusion: This study shows that addition of returned sludge to flash mixing can reduce the turbidity of samples.


M Malakootian, M. M Amin, H Jaafari Mansourian, N Jaafarzadeh,
Volume 4, Issue 4 (2 2012)
Abstract

Background and Objectives: Microbial fuel cells are the electrochemical exchangers that convert the microbial reduced power, generated via the metabolism of organic substrate, to electrical energy. The aim of this study is to find out the rate of produced electricity and also treatment rate of simulated wastewater of food industries using dual chamber microbial fuel cell (MFC) without mediator and catalyst.
Materials and Methods: MFC used in this study was consisted of two compartments including anaerobic anode chamber containing simulated food industries wastewater as synthetic substrate and aerobic cathode chamber containing phosphate buffer, respectively. These two chambers were separated by proton exchange membrane made of Nafion. Produced voltage and current intensity were measured using a digital ohm meter and the amount of electricity was calculated by Ohm's law. Effluent from the anode compartment was tested for COD, BOD5, NH3, P, TSS, VSS, SO42- and alkalinity  in accordance with the Standard Methods
Results: In this study, maximum current intensity and power production at anode surface in the OLR of 0.79 Kg/m3.d were measured as 1.71 mA and 140 mW/m2, respectively. The maximum voltage of 0.422 V was obtained in the OLR of 0.36 Kg/m3.d. The greatest columbic efficiency of the system was 15% in the OLR of 0.18 Kg/m3.d. Maximum removal efficiency of COD, BOD5, NH3, P, TSS, VSS, SO42- and alkalinity, were obtained 78, 72, 66, 7, 56, 49, 26 and 40%, respectively.
Conclusion: The findings showed that the MFC can be used as a new technology to produce electricity from renewable organic materials and for  the treatment of different municipal and industrial wastewaters such as food industries.


Hamid Reza Salari-Joo, Mohammad Reza Kalbassi, Seyed Ali Johari,
Volume 5, Issue 1 (6 2012)
Abstract

MicrosoftInternetExplorer4 Background and Objectives: Nanotechnology defined as understanding and controlling of materials at dimension between 1-100 nm, which show unusual physical and chemical properties. With Increasing development of nanotechnology, concerns associated with release of materials containing nanoparticles into the environment is rising. The purpose of this study is investigation of salinity effect on the acute toxicity of silver nanoparticles in rainbow trout fry (Oncorhynchusmykiss).
Materials and Methods: In order to conduct the toxicity tests, the Caspian Seawater(12±0.2 ppt) and (0.4 ppt) as sources of brackish water and freshwater were used, respectively. Toxicity of silvernano particles were evaluated in brackish water and freshwater at concentrations of1, 2, 4, 8, 16, 32and64ppm and  0.12, 0.25, 0.5, 1, 2, 4 and8 ppm, respectively. In addition, in order to investigate the quality of the used silver nanoparticles the Zetasizer, ICP, and TEM method were applied.
Results: Results of 96-hour median lethal concentration(LC50 96h), showed that toxicity of silver nanoparticles for rain bow trout fry in brackish water is 12 times less than its toxicity in freshwater.
Conclusion: According to the toxicity categories, analysis of the results showed that, for rainbow trout fry (1g), silver nanoparticles are classified as highly toxic agent substances in fresh water, and little toxic in brackish water, respectively.


Zahra Sajadi Mian Ab, Nasrollah Kalantari, Jaber Mozafarizadeh,
Volume 5, Issue 1 (6 2012)
Abstract

Background and Objectives: Due to population intensity and industrial activities, quality of groundwater is important in Bushehr province and in particularly in coastal areas. The salinity of groundwater in Asaluyeh plain is increasing from the heights towards the Persian gulf and in some places are not even applicable for irrigation.
Materials and Methods: In order to explore the source of the chloride anomaly, groundwater samples were analyzed and compared with the Persian Gulf samples. Also Water Samples Different diagrams were determined and the reasons of water salinity of Asaluyeh Plain were investigated.
Results: The results of chemical analyses showed the groundwater excessive salinity, especially near the sea. Based on correlation matrix, the highest correlation between the sodium and chlorine ions was observed.
Conclusion: The factors influencing on groundwater salinity in the plain varies and arising from solution of halite and gypsum from surrounding formations, suddenly increas sodium chloride in some parts of plain and forming Cl-Na water type. The results indicated that the Groundwater Type of Asaluyeh is Cl-Na and therefore it is classified as non-potable water.


Ruhollah Rostami, Ahmad Jonidi Jafari, Roshanak Rezaee Kalantari, Mitra Gholami,
Volume 5, Issue 1 (6 2012)
Abstract

Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 Background and Objectives:Benzene, toluene and Xylenes (BTX) are organic pollutants, which are mainly associated with oil and its derivatives. BTX is environmental contaminants and considered harmful to human health. Application of surface absorbents such as zeolite is one of several methods for the removal of these compounds. In this study, BTX compounds' removal efficiencies were investigated and compared by using clinoptilolite type zeolite and zeolite with copper oxide nanoparticles.
Materials and Methods: In this study, the modified zeolite by hydrochloric acid in the grain size 1-2 mm and modified zeolite with nano particle of copper oxide were used.  Artificially- Contaminated Air flow was used continuously .To determine BTX concentrations, samplings were done by charcoal tube in current input and output. The concentrations of contaminants were determined by gas chromatography with FID detector.
Results: Removal efficiency of benzene, toluene, p-xylene, m-xylene and o-xylene by clinoptilolite were 78.3%, 62.1%, 32.2% 32.15% and 18.8%, respectively. For the clinoptilolite containing copper oxide nano particles efficiency were 25.42%, 35.65%, 36.33%, 33.24% and 29.39%, respectively. Average removal efficiency of BTX compounds observed when the zeolite without nanoparticles used (43.31%) was more than zeolite with nanoparticles (32%). The results showed that the concentration of CO2 in the outlet air of the zeolite-containing nanoparticle (550 ppm) was more than the zeolite without nanoparticle (525 ppm).
Conclusion: Results showed that adding nanoparticles to the zeolite, although the removal efficiency of benzene and toluene can be reduced. The results showed that adding nanoparticles to the zeolite, although can be reduced removal efficiency of benzene and toluene, which may be due to occupying or blocking of the pollution absorption sites by the nanoparticles on the zeolite, but It cause promote more catalytic effect of zeolite in the decomposition process of contaminants by breaking the molecules of pollutants and their further degradation progress is done for conversion to carbon dioxide


Ali Khavanin, Ramezan Mirzaee, Maryam Safari, Ardalan Soleimanian,
Volume 5, Issue 2 (13 2012)
Abstract

Background and Objectives: city bus drivers, during driving, are always exposed to the whole body vibration. This can lead to central- neural, musculoskeletal, and blood circulation disorders and develop occupational diseases due to vibration. The objective of this descriptive- analytic study is to investigate Tehran bus drivers&apos exposure to the whole body vibration.
Materials and Methods: We measured parameters related to the whole body vibration, such as acceleration of the frequency weighted root sum of squares, the overall equivalent acceleration, vibration dose value, and crest factor were measured separately at three directions (X, Y, Z) in 80 buses in 5 different types, which were selected randomly. The results obtained were compared with ISO 2631: 1997 Standard, and finally permitted driving time was calculated for different buses.
Results: Acceleration of the frequency weighted root mean of squares at X, Y axes in all of the buses was below the district of health warning and at Z axis, it was in the district of health warning, while the overall equivalent acceleration in Icarus buses was above the district of health warning and in other buses it was in the district of health warning according to standard ISO 2631: 1997. Vibration dose value (VDV) was less than 8.5 and crest factor was less than 9 and in all of the buses, it was less than the suggested permitted limits of ISO 2631: 1997 standard. Moreover, permitted driving time was estimated less than 8 hours per day and Icarus buses had the most and Man buses had the least vibration acceleration, crest factor, and vibration dose value respectively.
Conclusion: According to the results obtained, there is the possibility of developing potential health risks in bus drivers therefore, it is recommended that the health and safe managers consider decrease of working hours and increase of rest time while purchasing new buses.


Mohammad Malakootian, Hassan Izanloo, Maryam Messerghany, Mohammad Mahdi Emamjomeh,
Volume 5, Issue 2 (13 2012)
Abstract

MicrosoftInternetExplorer4 Background and Objectives: leachate from municipal solid waste landfill is a strong sewage having hazardous toxic substances. It should be treated by choosing a simple, economical, and eco-friendly method. The aim of this study is reduction of COD from the Qom City landfill leachate using electrocoagulation process.  
Materials and Methods: The experimental study was carried out at bench scale using a batch reactor during 2010.  We used a Plexiglas reactor having 0.7 liter capacity, containing nine plate aluminum electrodes connected to a DC power supply (10-60V, 1-5A). Samples were collected in the middle of cell at regular (every 10 minutes) time intervals. The concentration of COD was determined using a COD analyzer. The effects of different parameters including current density (52.08, 69.44 mA/cm2), electrolyte time (10, 20,30,40,50 and 60 min), and voltage range (10, 20, 30, 40, 50 and 60 volt) were investigated.
Results: For a voltage of 60 V and electrolysis time 60 min, the COD removal efficiency was increased from 48.7% for 52.08 mA/cm2 to 77.4% for 69.44 mA/cm2. The highest TSS removal efficiency was obtained at the largest current input when the voltage and electrolysis time were kept at 60V and 60 min respectively.
Conclusion: The results showed that the highest COD removal efficiency (77.4%) was obtained when the current density was 69.44 Ma/cm2 and the voltage and electrolysis time were kept at 60V and 60 min respectively. Power consumption for this removal level was measured to be 431.26 kWh per kg COD removal. The results obtained revealed that the electrocoagulation technology is an effective treatment process for landfill leachate.

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