Showing 48 results for Dust
A Naghizadeh, Ah Mahvi, H Jabbari, A Dadpour4, M Karimi,
Volume 1, Issue 1 (10-2008)
Abstract
Background and Objectives: Silica is an inorganic material that found in the nature in various forms. The hazards of crystal of silica or α-quartz (free silica) is greater than other forms. Exposure to dust that contains free silica result to pulmonary injury and result to silicosis and death finally. The present research was conducted in order to evaluate the level of workers exposure to free silica in air of Khaf Iron stone quarries.Materials and methods: The exposure level to total and respiratory dust measured based on personal and environmental sampling methods and concentration of dust determined based on gravimetric method. For determination of amounts of free silica, dust samples analyses based on X-ray diffraction (XRD) method, and results compared with standard levels.Results: The maximum amount of total dust and free silica measured in stone breaking station (800±155mg/m3 and 26.11±6.7 mg/m3) and minimum of them measured in official and safeguarding station (8.28±2.2 mg/m3 and 0.012±0.0019 mg/m3). The maximum amount of respiratory dust and free silica measured in red mound digging number 1 (66.14±13.45 mg/m3 and 1.48±0.39 mg/m3) and minimum of them measured in air hammer machine station (5.26±2.62 mg/m3 and 0.01±0.005 mg/m3).Conclusion: Amount of total dust only in official and safeguarding station was lower than standard levels of Iran. Amount of respiratory dust in all stations was greater than Iran standard levels. Furthermore the level of respiratory free silica only in airy hammer machine station was lower than standard level of Iran. Regarding to this amounts it is so essential to that with applying different methods generation and emission of dust protected.
M Mosaferi, H Taghipour, A Ostadrahimi, Sh Nazmara,
Volume 1, Issue 2 (3-2009)
Abstract
Background and Objectives: In the production of some high-consumed food products like cake, biscuit, chocolate and spaghetti water is used in the preparing of primary material and in the kneading processes. At the present study microbiological and chemical quality of consumed water in food industries of East Azerbaijan Province were studied.
Materials and Methods: Eleven factories with different products were selected. Water samples were collected and analyzed regarding the microbiological contamination and chemical parameters, and heavy metals. In addition, condition of water quality in selected industry was surveyed during the summer.
Results: According to the results, monitoring of water quality in the studied industries is not suitable. The chemical characteristics of consumed water in those industries had major differences. Ni, Cr, Zn, Fe and Mn were present in all analyzed water but in lower concentration than national Maximum Contaminant Level (MCL). Pb was measured in higher concentration than MCL in spaghetti factory no. 2 and close to MCL in wiener and frankfurter and sugar industries. Cd was close to MCL in spaghetti factory no. 2 and wiener and frankfurter industries.
Conclusion: It was concluded that for the safety and health of food products the food industries should use the public water supply system as water source at least in food processing units or in the units of preparing of primary materials. Also for the preventing of chemical pollution of food products it is necessary, pay more attention to the subject of water quality control according to the special water standard of food industries, and using less volume of water in some food industry isn.t acceptable reason for neglecting of water quality monitoring and assessing. In addition it is required to analyze heavy metals in the final products of those industries.
N Jaafarzadeh Haghighi Fard, S Salamat, Z Rezvani, M.a Behrooz,
Volume 2, Issue 3 (11-2009)
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 (3-2010)
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.
A Ghanavati Hormozi, K. Naddafi, R. Nabizadeh Nodehi, N. Jaafarzadeh,
Volume 3, Issue 1 (4-2010)
Abstract
Background and Objectives:Fanavaran petrochemical company is located on the shore of Persian Gulf on west south of Iran, Imam Khomeini Bandar, petrochemical special economic zone with of 25 hectares area. Two units of this company, methanol unit with production capacity 1000000 tons/years and monoxide carbon unit with 140000 tons/years were studied for determination and emission factories of SO2, CO2, CO, NO, NO2, NOx Gases.
Materials and methods: With attention to project goals, for implementation of this project 14 months took into from April 2008 till June2009.For goals provide of mentioned research on this basis,case sampling were done from 3 emission sources by using of direct reading device of gas concentration according to standard methods of United State Environmental Protection Agency.
Results: Results of the study indicate that concentration of issued pollutant gases from these units is in the level lower than Iran department of environment standard level. The total amount of emission Factory of SO2, CO2, CO, NO, NO2, NOx gases diffused from these units are11.7×10-6 , 81/8×10-6, 0.14×10-6, 431.5×10-6, 19.2×10-6 , 681.2×10-6kg /tons million production in a year respectively.
Conclusion:Parameters which optimization is performed in accordance with them, include of additional air percentage, exit air temperature from pre heater, and fuel type, in fact with regarding these 3 factors. effects, the work is done in a manner that the amount of pollutants diffusion is near to minimum and the selected best fuel.
M.a Zazouli, E. Ghahramani, M. Ghorbanian Alahabad, A. Nikouie, M. Hashemi,
Volume 3, Issue 1 (4-2010)
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 Ahmadimoghadam, H Amiri,
Volume 3, Issue 2 (7-2010)
Abstract
Backgrounds and Objectives: Formaldehyde and phenol are key precursors in the industrial manufacture of resins. Toxicity of these compounds prevents function of microbial populations, so they affect the biological treatments. The aim of this study was investigation of TOC removal from phenol-formaldehyde resin manufacturing wastewater by electrocoagulation using Al- electrodes.
Materials and Methods: This study is the laboratory scale experiment was conducted as a pilot. Wastewater sample was adjusted in the desired pH, electrical conductivity and current density, then it was placed in to the reactor contains four electrodes in aluminum. The electrodes were connected to a DC power supply (0-40V, 0-3A). Samples were collected for TOC determination in the middle of cell at regular time intervals. Collected samples were analyzed using TOC analyzer.
Results:The results indicated that the optimum conditions for the removal of TOC were current density 75 A/m2, solution pH 4 and Conductivity 3 mS/cm. In this condition energy consumption was found 22.5 kWh m-3 after 60 min reaction.
Conclusion: This study shows that electrocoagulation of wastewater from phenol-formaldehyde resin manufacturing can be used as a pretreatment process.
M.h Dehghani, S Nasseri, M Ghaderpoori, A.h Mahvi, R Nabizadeh Nodehi,
Volume 3, Issue 4 (1-2011)
Abstract
Backgrounds and Objective: Surfactants are one of the largest pollutants which exist in urban and industrial wastewaters. Large quantities of surfactants have entered to the environment since last decade due to increased use of synthetic detergent in industrial and home consumptions.In this study, the efficiency of UV/H2O2 process in removal of linear alkylbenzane sulfonate (LAS) from aqueous solutions was investigated.
Materials and Methods: In this study methylene blue active substane(MBAS)method and spectrometery were used to determine anion and residual surfactant respectively. In this study important variables were H2O2 concentration, initial concentration of surfactant, pH and duration of UV radiation. The effect of UV/H2O2 process on the degradation of LAS was analyzed statistically by using Multiple Linear Regression test.
Results: The resulted showed that after 20 minute, ultraviolet radiation solely removed 38.44 percent of Anionic detergent, Hydrogen peroxide showed no significant removal of detergent solution in the time course study. The efficiency of UV/H2O2 process in 10, 20 and 30 minute were to 86.2, 90 and 96.5 %, respectively.
Conclusion: The results showed that the efficiency of ultraviolet radiation and hydrogen peroxide process in anionic detergent was not significant thoogh it was considerable in combination process (UV/H2O2).
P Bahmani, R Rezaei Kalantary, M Gholami, A Jonidi Jafari, Z Javadi,
Volume 3, Issue 4 (1-2011)
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 Manshouri, A Yazdanbakhsh, M Sardar, A Sheykh Mohammadi,
Volume 3, Issue 4 (1-2011)
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. A Karami, M Farzadkia, A Jonidi Jaafari, R Nabizade, M. R Gohari, M Karimaee,
Volume 4, Issue 4 (3-2012)
Abstract
Background and Objectives: In recent years, poor industrial waste managements have created many crises in human societies. The aim of this study was to investigate industrial waste management located between Tehran and Karaj zone in 2009-2010.
Materials and Methods: This study is descriptive and sectional which was done by site visits, (Iranian environmental protection organization) use of questionnaires, database production and results analysis. The questionnaire consisted of 45 questions mainly about industrial waste quantity, quality and management. Total number of industries with over 50 personnel's, calculated as 283. Class-weighted sampling was used in which the sample size contained 50 industries.
Results: Total generated industrial waste was 123451, kg per day. Major hazardous waste generated in industrial sections included: chemical and plastic making. About 45.28% of waste generated disposed by private sectors. Landfill with 62% and reuse with 17% were the first and second alternative of common methods for final disposal of solid waste in this zone.
Conclusion: In order to reduce hazardous waste generation in this zone, reuse and recovery maximization of the waste must be noted in short-term. In long-term, some industries such as chemical-plastic and electronics which have high rate of hazardous waste production must be replaced with other industries with low rate production, such as wood-cellulose and paper industries.
Amir Bagheri, Gholamreza Moussavi, Ali Khavanin,
Volume 5, Issue 2 (10-2012)
Abstract
MicrosoftInternetExplorer4
Background and Objectives: Formaldehyde is a toxic substance and harmful to human
beings and the environmental health. Therefore, the effluents containing
formaldehyde have to be efficiently treated before discharging into the
environment. This study was aimed at investigating the efficiency of
Electro-Fenton (EF) Process in pre-treating industrial wastewater containing
high concentrations of formaldehyde.
Materials and Methods: The effect of the important operational variables including pH, current
density, H
2O
2 dosage, and reaction time were evaluated on the degradation of
7500 mg/L formaldehyde using batch tests. The EFP batch reactor was consisted
of a cylindrical glass column with 5.20 cm in internal diameter and 34.50 cm in
height. Working volume of the reactor was 500 mL.
Results: The maximum
formaldehyde removal was obtained at alkaline pH of 10, H
2O
2 concentration of
10 mM/min, current intensity 8.5 mA/cm2, and the reaction time of 6 minute.
Furthermore, aerating the EFP cell could enhance the formaldehyde removal.
Complete removal of formaldehyde was obtained under the abovementioned
operational conditions.
Conclusion: This study
demonstrated that the EFP is capable of reducing high concentration of
formaldehyde (7500 mg/l) to the level suitable for biological post-treatment.
Sohrab Delangizan, Zainab Jafari Motlagh,
Volume 6, Issue 1 (5-2013)
Abstract
Background
and Objectives:
Dust phenomenon has adverse effects on the health of the population.Due to the
increasing concentration of Kermanshah dust phenomenon in recent years, The aim
of this study was to measure the concentration of the sensitivity coefficients
between dust phenomenon hospitalization and mortality rates for heart and
respiratory.
Materials
and Methods:
This was a descriptive study in which we studied the sensitivity coefficient of
hospitalization and mortality rates for heart disease and respiratory to
changes of dust concentration.. The study duration was during March-September
2010 and 2011. We collected the dust
phenomenon data from Kermanshah Province Environmental Protection Department.
The admissions and mortality of the cardiovascular and respiratory sufferers
was collected from the Imam Ali, Imam
Reza, and Imam Khomeini governmental hosiptals in Kermanshah.
Results: 1% increase in air pollution
caused by the dust phenomenon will result in increasing about 0.5 % of the respiratory patients, 1% cardiac patients,
and about 0.3% of the heart disease mortality. The relationship between dust
phenomenon and respiratory sufferers was statistically not significant.
Conclusions: We found that respiratory and
cardiovascular hospital admission has a high sensitivity to dust phenomenon.
This sensitivity has increased from 2010 to 2011. This sensitivity was greater
for males than females. At least, during
March-September 2010, for every 100% increase in the concentration of dust
phenomenon, cardiovascular mortality increased by 29%.
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Ahmad Reza Yazdanbakhsh, Akbar Eslami, Akram Najafi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and objectives: Formaldehyde is one of the compounds widely used in various industries hence, its discharge into the effluent is unavoidable. Exposure to formaldehyde has a significant health effects. To prevent these issues, treatment of wastewater containing formaldehyde is necessary. The purpose of this study was to determine the performance of aerobic sequencing batch reactor (SBR) in removing formaldehyde from wastewater. Methods: We used a SBR having a total volume of 6.15 liters and an effective volume of 4 liters. The formaldehyde and COD removal efficiency of SBR was evaluated by applying loading rate of 0.031 to 0.156 kgCOD/m3.h. Four cycles of 6, 8, 10, and 12 hours were considered to investigate retention time effect onto the reactor efficiency. Results: Acclimation of microorganism with formaldehyde was achieved after about 30 days. We found that a retention time lower than an hour is not enough for achieving an acceptable efficiency. The maximum removal efficiency (90.52% for COD and 95.32% for formaldehyde) was observed at organic loading rate of 0.031 kg COD/m3.h and 12 hour retention time. The removal efficiency decreased to 46.44% for COD and 69.12%, for formaldehyde with increasing the organic loading rate to 0.156 kg COD/m3.h. The maximum concentration of MLSS was measured 2863 mg / L at organic loading rate of 0.091 kg COD/m3.h. Conclusion: The results showed that SBR could be applied as a practical, effective, and reliable technology for treatment of wastewater containing formaldehyde.
Kamiar Yaghmaeian , Ali Akbar Roudbari, Saeeid Nazemi,
Volume 6, Issue 3 (12-2013)
Abstract
Background & Objectives: The aim of the study was to design and implement integrated solid wastes management pattern in Shahroud industrial area, to evaluate the results, and to determine possible performance problems.
Materials & Methods: This cross - sectional study was carried out for 4 years in Shahroud industrial area and the implementation process included: 1. qualitative and quantitative analysis of all solid wastes generated in the area, 2. determining the current state of solid waste management in the area and identifying programs conducted, 3. designing and implementation of integrated management pattern including design and implementation of training programs, laws, penalties and incentives, and illustrating and implementing programs for all factories, and 4. monitoring the implementation process and determining the results.
Results: Annually, 1,728 tons of solid waste is generated in the area including 1603 tons of industrial waste and 125 tons of municipal wastes. By implementing this pattern, two separated systems of collection and recycling of domestic and industrial waste were launched in this area. Moreover, consistent with the goals, the amount of solid waste generated and disposed in 2011 was 51.5 and 28.6 kg per 100 million Rials production respectively. In addition, 42 and 40% of the industrial waste and paper were recycled.
Conclusion: Results showed that implementation of this pattern, i.e. running source separation, training programs, capacity building, providing technical services, completing chain of industries and strengthening the cooperation between industrial estate management and industrial units could greatly reduce the waste management problems.
Gh Asgari, A. R. Rahmani, A. R. Dehghanian, A. R. Soltanian,
Volume 7, Issue 1 (7-2014)
Abstract
Background and Objectives: In this experimental study, we used Analytical Hierarchy Process method to determine the best wastewater treatment process for dairy products factories. That is a multi-criteria decision making techniques and is based on expert knowledge. Materials and Methods: First, we formed the hierarchical structure and defined the main criteria and indicators. Then, we investigated the current situation of the treatment process through field observations and conducting influent-effluent analysis. Later, we converted the results obtained into quantitative indices. Then we weighted the main criteria, and their related sub criteria, depending on existing conditions we performed the experiments required and considered the experts ideas. Finally, Evaluation and prioritization of the options was conducted using Expert choice software. Then the sensitivity analysis was performed for main criteria and we evaluated the influence of the parameters weight change on the options. Results: In comparison with the main criteria, environmental criteria were more important followed by engineering criteria, economic and management criteria. Conclusions: Due to the influence of various parameters in choosing optimal wastewater treatment, Multi-criteria decision-making methods are necessary. Finally, “UASB + Aeration” was found to be the first priority followed by “Anaerobic filter + Aeration”, “Anaerobic lagoon + Aeration (2) + Sedimentation (2)”,” Anaerobic filter + Aeration (2) + Sedimentation (2)”. “Septic tank + Trickling filter + Aeration” system was found to be less preferable than other options.
M. Arbabi, M.a. Ahmadi, M. Sedehi,
Volume 7, Issue 3 (5-2014)
Abstract
Background and Objectives: Bakery’s yeast industry wastewater contains various pollutants and is generally characterized with high chemical oxygen demand (COD), dark color, high-nitrogen and sulfate and non-biodegradable organic pollutants. Having persistent soluble colored compounds (called melanoidins), effluent from yeast industry is a major source of water and soil pollution. The aim of this study was to evaluate advanced oxidation efficiency using Fenton process for COD and color removal from bakery’s yeast wastewater. Materials and Methods: This was an experimental- laboratory scale study. In this study, the effect of time and Fenton concentrations were tested for COD and color removal from bakery’s yeast wastewater. The sample used for this study was yeast effluent from Separator 2 with initial concentrations of COD and color of 5300 mg/L and 6950 pt-co respectively. In order to obtain the optimum operating conditions of the process, Taguchi analysis method was used. Experiments were carried out in five stages of the time in the range of 15, 30, 45, 60 and 75 min with various concentrations of hydrogen peroxide (e.g., 0.02, 0.04, 0.06, 0.08, and 0.1 molar) and concentrations of Fe2+ (e.g., 0.01, 0.02, 0.03, 0.04, and 0.05 molar) at pH = 3. Jar test method was used to determine the best operating conditions including: reaction time, dosages of hydrogen peroxide and Fe2+. Results: According to Taguchi method and SN-ratio analysis, the best H2O2/Fe2+ dosages were 0.08/0.04 molar at pH 3 and in reaction time of 30 min for removal of COD and color. For these conditions, the maximum COD and color removal efficiencies were 63 and 69 percent respectively. Based on the results, with increasing reaction time, there was no perceptible change in the removal efficiency. Conclusion: It can be concluded that Fenton’s oxidation method can be used successfully, as an alternative option to the design and choice of color and COD removal from strength industrial wastewaters e.g., bakery’s yeast industry.
M Rajabi, B Souri,
Volume 8, Issue 1 (8-2015)
Abstract
Background & Objectives: Dust storms happening frequently in arid and semiarid regions of the world carry huge amount of particulate matters hence, these are recognized as one of the most important environmental issues at regional and international scales. This study aimed to evaluate heavy metals laden dustfall particles in Sanandaj, Khoramabad, and Andimeshk cities, West Iran. Materials & Methods: Sampling of dustfall particles was conducted once every 10 days from June 20, 2012 for one year at three stations of Sanandaj, Khorramabad, and Andimeshk simultaneously using Deposit Gauge Method. The concentration of Fe and Mn were measured using Flame Atomic Absorption Spectroscopy and Furnace Atomic Absorption Spectroscopy was used for analyzing Ni, Cr, Ag, As, Cu, and Zn. Then, pollution levels for the heavy metals were evaluated using Geo-Accumulation Index (Igeo) and Integrated Pollution Index (IPI). Mineralogy and morphology of the dustfall particles were inspected using X-ray diffraction and scanning electron microscopy. Results: Igeo index indicated that levels of pollution for Ag and Cu were higher than As and Zn among the dustfall particles of the three stations whereas the concentrations of the other heavy metals were not evaluated as contaminant. Moreover, means of IPI values calculated for stations of Sanandaj, Khorramabad, and Andimeshk were 2.86, 1.55 and 1.40 respectively. X-ray diffraction revealed abundance of silicate (quartz) and carbonate (calcite) minerals in dustfall particles. Additionally, scanning electron microscopy emphasized on similarity of shape of dustfall particles in the three stations. Conclusion: Although mean of dustfall particles on area unit in Sanandaj station was less than Khorramabad and Andimeshk, heavy metals concentration was relatively higher among the sampled dustfall particles.
. P Broomandi, A Bakhtiar Pour,
Volume 9, Issue 4 (3-2017)
Abstract
Background and Objective: The aim of this study was to investigate the physico-chemical properties, size distribution and shape of the falling mineral dusts over Masjed Soleyman and to identify their origins. Also, seasonal and annual variations of climatic parameters and their relation with dust storm occurrence were investigated.
Materials and Methods: The collected samples were as result of dry deposition process during warm season in 2013. Particle size distribution was determined by laser size diffraction. Chemical and mineralogical compositions were measured with atomic absorption spectrophotometer (AAS) and X-ray diffraction (XRD). Crustal and non-crustal origins for elements in the dust samples were determined using enrichment factor (EF). In addition, dust storm sources were identified using the Hybrid Single Particle Lagrangian Integrated Trajectory Model (HYSPLIT.4).
Results: The study of the annual and seasonal changes in meteorological parameters associated with the occurrence of dust storms indicated an agreement between the occurrence of dusty days, temperature and rainfall in summer. The chemical and mineralogical analysis of dust particles demonstrated that the likely origin of these particles is of neighboring countries in the South West of Iran. Also, some of the detected trace elements had non-crustal sources.
Conclusion: Using HYSPLIT.4 results, it was concluded that the main origin of dust storms are North West of Iraq and East of Syria in Masjed Soleyman.
Q Moradi, R Mirzaei,
Volume 9, Issue 4 (3-2017)
Abstract
Background and Objective: Street dust is consisting of solid particles with complex compositions which can be an appropriate indicator to determine urban environmental contamination. Therefore, the purpose of this study was to determine spatial patterns and heavy metals contamination in the street dusts of Kashan.
Materials and Methods: A total of 48 urban street dust samples were collected and total concentrations of Pb, Cu, Zn, Fe, Cr, Ni, and Cd were determined in the dust samples. The geoaccumulation index was applied to assess heavy metals contamination. In addition, the spatial patterns of heavy metals concentrations in the street dust were determined using GIS.
Results: The results showed that the average concentrations of Zn, Cd, Cr, Fe, Ni, Pb and Cu in the street dust samples were 237.21, 0.43, 37.12, 16589.77, 13.62, 45.18 and 45.58 mg/kg, respectively. The average concentrations of Pb, Cu, Zn, and Fe were higher than their local background values. Based on geoaccumulation index, the heavy metals in the street dust were in the following decreasing order: Pb > Zn > Cu > Ni > Cd > Cr. According to the spatial analysis results, higher concentrations of heavy metals were observed in the city center and Kashan-Qom highway; whereas, lower concentrations were found in the residential regions.
Conclusion: Based on the obtained results, it seems the high concentrations of Pb, Zn and Cu and to a lesser extent Fe and Cd concentrations in the dust samples was derived from anthropogenic activities; whereas the concentration of Cr and Ni has been mostly affected by natural sources. The high concentrations of heavy metals in the street dusts of Kashan could be attributed to vehicle emissions and industrial activities.
