Showing 47 results for Nabizadeh
Amir Hossein Mahvi, Noushin Rastkari, Ramin Nabizadeh Nodehi, Shahrokh Nazmara, Simin Nasseri, Mahboobeh Ghoochani,
Volume 6, Issue 3 (12-2013)
Abstract
Background and Objectives:Chlorination is the most common method of water disinfection. Chlorine reaction with natural organic compounds nor removed completely during treatment process would result in forming disinfection byproducts. Followed by trihalomethanes, Haloaceticacides are the second main byproducts of chlorination in water. The research works conducted in Iran have assessed trihalomethanes. Hence, this is the first time we are reporting haloacetic acids in Iran.
Materials and Methodology: We collected samples from surface water resources and treated water in Tehran for six consecutive months (first half, 2010). We measured temperature, pH, UV adsorption at 254 nm and TOC in each surface water sample and analyzed pH, residual chlorine, and haloacetic acids in the treated water samples.
Results: We found that TOC in surface water resources is 3.6-4.42 and 1.78-2.71 mg/l in spring and summer respectively. Moreover, haloacetic acids concentration was found to be 41.7-55.56 and 34.83-43.73 μg/l in spring and summer respectively.
Conclusion: Our results revealed that concentration of NOM, TOC, and HAAs was more in spring than summer. In addition, concentration of HAAs was depended up on NOM and TOC. Considering maximum permeable concentration of HAAs (60 μg/l) by EPA, it can be claimed that concentration of HAAs was less than the maximum permissible level in all of the samples. However, the immanency of the monitored values to the standard values can be a warning for concerned authorities in water industry.
Mahdi Sadeghi, Kazem Naddafi, Ramin Nabizadeh,
Volume 7, Issue 2 (10-2014)
Abstract
Background and objective: Perchloroethylene is a chlorinated hydrocarbon used as a solvent in many industries and services activities such as dry cleaning and auto industry as degreasing. We carried out a bioassay using Daphnia Magna in order to determine the ecological effects of wastewater treatment through applying advanced oxidation processes (ultrasonic, ultraviolet irradiation and hydrogen peroxide processes) for removal of perchloroethylene. Materials and Methods: Due to the sensitivity of Daphnia and reports indicating this species is the most sensitive aquatic invertebrate to a variety of organic compounds, toxicity of perchloroethylene and its intermediate degradation products during applying different processes was tested using Daphnia. Lethal concentration (LC50) and toxic units (TU) were determined. In to determine toxicity of perchloroethylene, its stock solution was prepared at a concentration of 100 mg/L. Then, nine samples each containing 0 (control), 5, 10, 20, 30, 40, 50, 75, and 100% by volume of the primary stock solution were prepared. To determine the toxicity of the intermediate products of perchloroethylene by ultrasonic, photolysis, photolysis with hydrogen peroxide and photosonic processes, an initial concentration of perchloroethylene for each reactor (100 mg/L) was taken. All experiments were carried out at the Laboratory of Microbiology, Faculty of Health, Tehran University of Medical Sciences, Iran. Results: It was found that the 24 h LC50 for perchloroethylene on Daphnia Magna was 35.51 mg /L. The 48 h, 72 h and 96 h LC50 of perchloroethylene were 28.058, 21.033, and 19.27 mg/L respectively. Toxicity of perchloroethylene was decreased after oxidation processes. Conclusion: The toxicity after hybrid processes was lower than the single processes. The toxicity reduction was the same during all time period. Hence, the hypothesis of reducing toxicity of the intermediate products of perchloroethylene degradation after the abovementioned processes is acceptable. It is noteworthy that although there are different intermediate compounds in the effluent of various chemical oxidation processes, , but they are less toxic compared with the original perchloroethylene this may be due to the partially concentration of intermediate products that will decrease toxicity.
R Nabizadeh, K Naddafi, A Jonidi Jafari, M Yunesian, A Koolivand,
Volume 7, Issue 3 (5-2014)
Abstract
Background & Objectives: Remaining crude oil in storage tanks lead to accumulation of oily sludge at the bottom of the tank, which should be treated and disposed of in a suitable manner. The aim of the present study was to investigate the efficiency of chemical oxidation using H2O2 and Fenton’s reagent in removal of Total Petroleum Hydrocarbons (TPH) from bottom sludge of crude oil storage tanks. Materials & methods: In this experimental study, hydrogen peroxide and Fenton’s reagent were added to the sludge in six concentrations including 2, 5, 10, 15, 20, and 30% (w w-1) and TPH was measured for a period of 24 and 48 h of reaction time. The oxidants were added in a single and stepwise addition way, both to the pristine and saturated sludge. The elemental analysis of sludge and TPH measurement were carried out using ICP and TNRCC methods respectively. Results: The mean TPH removal of 2, 5, 10, 15, 20, and 30% oxidant concentrations were 1.55, 9.03, 23.85, 33.97, 41.23, and 53.03%, respectively. The highest removal efficiency was achieved in stepwise addition to the saturated sludge. Increasing oxidation time from 24 to 48 h had a little effect on increase in TPH removal. Moreover, the removal efficiency of H2O2 and Fenton was nearly similar. Conclusions: Mere application of chemical oxidation is not capable of complete treatment of the sludge but it is an effective process as a pre-treatment step for decreasing toxicity and increasing its biodegradability.
E. Karimi Pasandideh, R. Rezaei Kalantary, S. Nasseri, A. H. Mahvi, R. Nabizadeh, A. Esrafili,
Volume 7, Issue 3 (5-2014)
Abstract
Background and Objective: The presence of natural organic materials (NOM) in water resources affects its quality (i.e. color, odor, and taste). In addition, it leads to the fouling of filters and membranes and reduces water treatment efficiency during flocculation/ coagulation. Moreover, NOM reacts with disinfectants and produces byproducts (DBPs), which are harmful to human health. Magnetic nanoparticles have been reported as effective adsorbents for the removal of pollutants from the aqueous media. In this study, we applied SiO2coating on these nanoparticles in order to enhance their stability and dispersion in aqueous media and investigated their capability in NOM adsorption from water. Materials and Methods: Iron oxide magnetic nanoparticles were prepared by co-precipitation. Then, we added Tetraethoxysilane (TEOS) to the solution in order to coat it with SiO2 . The adsorbent characteristics were determined by SEM and XRD. Then, we carried out the adsorption experiments under different pH(3-12) and contact time (5-240 min)performance conditions. The adsorption kinetic was determined with respect to different Humic acid adsorption times. Later, we determined the effect of different concentrations of adsorbent on different concentrations of Humic acid, and Langmuir and Freundlich coefficients based on the optimum conditions. Results: The morphology investigation of adsorbent showed the average size of Fe3O4/SiO2nanoparticles was 30-130 nm. The pH value of 10.5 and the contact time of 90 min at room temperature were determined as optimum conditions for removal of humic acid using Fe3O4/SiO2 nanoparticles. The maximum adsorption capacity of Fe3O4/SiO2 was192.30. The adsorption isotherm was fitted well by Langmuir model (R2>0.90) and the pseudo-second order model (R2>0.98) could better explain humic acid adsorption. Conclusion: Having high number of active surface sites, magnetic properties, easily separation using magnetic field, and its cost-effectiveness, the Fe3O4/SiO2 nanoparticles could be used as an efficient adsorbent in removal of humic acid from water.
M Abtahi, K Naddafi, A.r Mesdaghinia, K Yaghmaeian, R Nabizadeh, N Jaafarzadeh, N Rastkari, R Saeedi, Sh Nazmara,
Volume 7, Issue 4 (1-2015)
Abstract
Background and objectives: Dichloromethane (DCM) is one of the hazardous contaminants of the environment, especially ambient air that threatens human health at both acute and chronic exposures. In this study, the performance of a pilot-scale hybrid bubble column/biofilter (HBCB) bioreactor was studied for the removal of DCM from waste gas streams at steady state. Materials and methods: The experiments were conducted in four stages with relatively constant concentrations of DCM (approximately 240 ppm) and variable empty bed residence time (EBRT) of 50, 100, 150 and 200 s. In addition to determining DCM removal rate and efficiency, quality parameters of mixed liquor of the bubble column bioreactor were studied and kinetic of biofiltration was analyzed. Results: The average DCM removal efficiency of the HBCB bioreactor at EBRT of 200 and 150 s were 79 and 71% respectively. However, further reduction of EBRT resulted in significantly decreased DCM removal efficiency, so that at EBRT of 50 s, the DCM removal efficiency decreased to 32%. In addition, the EBRT reduction from 200 s to 50 s through increasing DCM loading rate resulted in increasing DCM removal rate from 12.1 to 19.6 g/m3.h. The results of kinetic analysis showed that the kinetic data of biofiltration were in the best fitness with the first order rate equation (R2>0.99 and &epsilon%<2.2) and the DCM removal rate constant was determined 0.0114 s-1. The mixed liquor characterization indicated that the daily adjustment of pH and EC was sufficient to prevent any limitation in the performance of the HBCB bioreactor. Conclusion: This study indicated that the DCM removal rate and efficiency of the HBCB bioreactor were relatively high and the HBCB bioreactor had reliable performance during the variable operational conditions.
A Gholampour, R Nabizadeh, M. S. Hassanvand, H Taghipour, S Faridi, A.h. Mahvi,
Volume 7, Issue 4 (1-2015)
Abstract
Background & Objectives: Determining the impacts of air pollution in cities is facing two major challenges first, the limited data on the health effects of pollutants, and secondly, the lack of information on exposure to air pollutants and their concentration. This is an applied-observational carried out to determine the concentration, seasonal changes, and to estimate the health impacts attributed to the particulate matters in Tabriz during September 2012 to July 2013. Materials and Methods: The particulate matters were sampled using high volume sampler and were analyzed using portable HAZ-DUST EPAM-5000. The health impacts of particulate matterswere estimated using AirQ software developed by W.H.O. Results: The annual mean concentration of TSP, PM10, PM2.5, and PM1 in the urban sampling site were 139, 83, 38, and 27 µg/m3 respectively. In addition, these concentrations were 178, 110, 40, and 27µg/m3 in industrial area. The average of PM10/TSP, PM2.5/PM10, PM1/PM10, and PM1/PM2.5 ratio level was 0.6, 0.48, 0.33, and 0.7 in the urban areas and 0.61, 0.37, 0.28, and 0.77 in the industrial areas respectively. The total mortalities associated with the TSP, PM10, and PM2.5 concentrations were estimated as 327, 363, and 360 respectively. Nevertheless, the calculated cardiovascular mortality for TSP and PM10 were estimated to be 202 and 227 respectively. Conclusion: This research found that the concentrations of PM10 and PM2.5 were 73 and 69% more than National Standard and 8 and 5% more than USEPA Standards respectively. In Tabriz, especially industrial area, the soils of surrounding ground and re-suspension of particles fromcontaminated soils have a significant contribution to particulate emissions.
A Heidari, R Nabizadeh, M Alimohammadi, M Gholami, A.h Mahvi,
Volume 8, Issue 1 (8-2015)
Abstract
Background and Objectives: Reduction of released extracellular polymeric substances (EPS) during sludge dewatering is one of the main challenges in sludge treatment process. The aim of this study was to investigate the EPS quantity changes within sludge dewatering by continues ultrasonic – electrocoagulation (US – EC) reactor under different conditions and to determine the most efficient case for reducing these substances. Materials and Methods: In this study, the EPS quantity changes in supernatant were compared after undergoing different conditions of ultrasonic (frequency of 35 and 130 KHz, detention time of 3,5,10, and 30 min) and electrocoagulation (voltage of 20, 30, and 40 V, detention time of 10, 20, and 30 min) processes were compared. Results: The research found that the maximum efficiency of the US-EC reactor was achieved at a frequency of 35 KHz and detention time of 5 min for ultrasonic with voltage of 40 V and at detention time of 30 min for electrocoagulation process as under these conditions total EPS concentration reduced by 69%. Conclusion: According to the results achieved, US – EC reactor significantly reduced the released EPS in supernatant in addition to dewatering sludge.
M Jahangiri-Rad, R Nabizadeh, J Nouri, M Yunesian, F Moattar,
Volume 8, Issue 1 (8-2015)
Abstract
Background and Objective: Nitrate is one of the dissolved anions having great health importance in water. Human activities and natural sources are considered as the main roots of nitrate intrusion in to water bodies. The main objective of this paper was to study nitrate removal by packed bed column filled with (PAN)-oxime-nano Fe2O3. Materials and Methods: PAN-oxime-nano Fe2O3 were synthesized and used as an adsorbent in glass column for the removal of nitrate from aqueous solution. Nitrate solution tank was set above the prepared column. The effect of factors, such as flow rate (2, 5, and 7 mL/min) and bed depth (5, 10, and 15 cm) were studied. Results: It was found that the data fit well with Thomas model and breakthrough curve was designed accordingly. The column performed well at lowest flow rate. As the flow rates and time increased, earlier breakthrough was observed. The column breakthrough time (Ce/C0 = 0.05) was reduced from 9 to 4 h, as the flow rates increased from2 to 7 mL/min. Conclusion: fixed-bed using PAN-oxime-nano Fe2O3 exhibited good removal of nitrate. The adsorption studies showed that at longer bed depth, better removal of nitrate would be achieved. Thomas model was suitable for the normal description of breakthrough curve at the experimental condition. The data also were in good agreement with logistic regression.
H Zarei, A.h Mahvi, S Nasseri, R Nabizadeh Noudehi, F Shemirani,
Volume 8, Issue 3 (12-2015)
Abstract
Objective and Background: Fluoride is an element widely found in the earth crust. Advantages and disadvantages of fluoride in the human body are depended on its concentration. Long-term consumption of drinking water contaminated with arsenic can cause adverse health effects such as skin lesions and cancer in humans. The aim of this study was to study efficiency of nano alumina on multi walled carbon nano tube for removal As(V) and fluoride from aqueous solution.
Materials and Method: In this study, nano-scale crystalline alumina was synthesized on single walled carbon nanotube by sol-gel method for using as a sorbent for solid phase extraction of Fluorine ion and arsenic(V). Response surface methodology based on Box-Behnken was used to assess the effect of independent variables on the response function and prediction of the best response value. In this study, effect of different parameters, such as contact time (10 to 120 min), pH (3-9), adsorbent dosage (0.25-1.5 g/L) and initial concentration of fluoride (2-8 mg/L) on efficiency of process was investigated. The structure of nano-scale alumina on multi walled carbon nano tube was determined by XRD and SEM techniques. Moreover, Freundlich and Langmuir isotherm models were used to calculate equilibrium constant.
Results: It was found that by increasing contact time and adsorbent dosage the rate of fluoride removal increased. However, by increasing pH and initial concentration the efficiency of fluoride removal decreased. High value for R2 (0.94) shows that removal of arsenic(V) can be described by this model. The Freundlich isotherm was the best fitted graph for experimental data with R2 more than 0.997.
Conclusion: In this study, it was observed that efficiency of arsenic(V) and fluoride removal was greatly increased by using nano-scale alumina on multi walled carbon nanotubes (MWCNTs).
K Naddafi, R Nabizadeh, S Nasseri, K Yaghmaeian, A Koolivand,
Volume 8, Issue 3 (12-2015)
Abstract
Background and Objectives: Remaining of crude oil in storage tanks usually results in accumulating oily sludge at the bottom of the tank, which should be treated and disposed of in a suitable manner. The efficiency of in-vessel composting process in removing total petroleum hydrocarbons (TPH) from bottom sludge of crude oil storage tanks was investigated in the present study.
Material and methods: The sludge was mixed with immature compost at the ratios of 1:0 (as control), 1:2, 1:4, 1:6, 1:8, and 1:10 (as dry basis) with the initial C:N:P and moisture content of 100:5:1 and 55% respectively for a period of 10 weeks. The moisture adjustment and mixing process were done 3 times a day during the composting period. Sampling and analysis of TPH and pH were done every week and every two days, respectively.
Results: TPH removal in the 1:2, 1:4, 1:6, 1:8, and 1:10 composting reactors was 66.59, 73.19, 74.81, 80.20, and 79.91%, respectively. Thus, initial adjustment of sludge to immature compost ratios plays a great role in reduction of TPH. The results of the control reactors indicated that the main mechanism of TPH removal in the composting reactors was biological process.
Conclusions: In-vessel composting by addition of immature compost as amendment is a viable choice for bioremediation of the bottom sludge of crude oil storage tanks.
K Yaghmaeian, N Jaafarzadeh, R Nabizadeh, H Rasoulzadeh, B Akbarpour,
Volume 8, Issue 4 (3-2016)
Abstract
Background and Objective: Arsenic is one of the most toxic pollutants in groundwater and surface water. Arsenic could have lots of adverse impacts on human health. Therefore, access to new technologies is required to achieve the arsenic standard.
Materials and Methods: The present study was conducted at laboratory scale in non-continuous batches. The adsorbent of zero-valent iron nanoparticles -Chitosan was produced through reducing ferric iron by sodium borohydride (NaBH4) in the presence of chitosan as a stabilizer. At first, the effect of various parameters such as contact time (5-120 min), pH (3-10), adsorbent dose (0.3-3.5 g/L) and initial concentration of arsenate (2-10 mg/L) were investigated on process efficiency. Then optimum conditions in terms of contact time, pH, adsorbent dose and initial concentration of arsenate were determined by RSM method. Freundlich and Langmuir isotherm model equilibrium constant, pseudo-first and second order kinetic constants were calculated. The residual arsenate was measured y using ICP-AES.
Results: The optimum values based on RSM for pH, absorbent dose, contact time, and initial concentration of arsenate were 7.16, 3.04 g/L, 91.48 min, and 9.71 mg/L respectively. Langmuir isotherm with R2= 0.9904 for Arsenate was the best graph for the experimental data. According to Langmuir isotherm model, the maximum amount of arsenate adsorption was 135.14mg/g. . The investigation of arsenate adsorption kinetics showed that arsenate adsorption follows the pseudo-second kinetics model.
Conclusion: This research showed that the adsorption process is depended on pH. With increasing pH, the ability of amine groups in chitosan are decreased to protonation, caused to decrease the efficiency of arsenate removal at high pH.
H Aslani, R Nabizadeh,
Volume 8, Issue 4 (3-2016)
Abstract
Background and Objectives: Considering the complexity, cost, and time-consuming techniques of detecting Cryptosporidium oocysts and Giardia cysts, B. subtilits spores have been introduced as microbial indicators of these pathogens to evaluate the efficacy of disinfection studies. The present study was aimed to investigate the feasibility of B. subtilis spores inactivation using hydrogen peroxide combined with copper and silver ions. A new glutaraldehyde based compound used for surface disinfection was also tested.
Materials and Methods: In order to sporulation, vegetative bacteria were allowed to grow on a medium with insufficient nutrients, and after 5 days incubation at 37˚C, spores were washed and purified. Spore suspension was used to prepare synthetic water. Disinfection efficiency was reported as logarithmic decrease of initial spore count.
Results: This research found that none of the disinfection compounds was able to spore inactivation in low initial concentration. The highest spore reduction efficiency was related to HP/Cu+2 with 1.48 log inactivation, and HP/Ag+ compound placed in the second rank with 1.03 log reduction. Maximum spore reduction of 0.6 log was achieved when glutaraldehyde based disinfectant was used in disinfection process.
Conclusion: According to the results, it can be concluded that spores are very resistant even to combination of disinfectants. Spore reduction potential of the studied compounds was as follows: HP/Cu+2> HP/Ag+> glutaraldehyde based compound.
B Sepehrnia, R Nabizadeh, A.h Mahvi, S Naseri,
Volume 9, Issue 1 (6-2016)
Abstract
Background and Objective: In this study, WQI was estimated using an Iranian software called IWQIS to assess drinking water quality in Ray Township distribution systems.
Materials and Methods: The assessment of 73 samples of drinking water during 2013 and the comparison of 18 physicochemical parameters with the standard Code of 1053 (Iran National Standard) was done.
Results: The results showed that the concentration of 7 parameters is out of normal range in special percentage of the samples. Those parameters are as follow: total hardness (31.5%), Mg (46.6%), nitrate (50.68%), Na (45.2%), F (42.46%), Cl (2.7%), Sulfate (28.76%) of samples. The medium concentration of theses parameters was: total hardness (375 mg/L), Mg (32 mg/L), Nitrate (47.43 mg/L), Na (187 mg/L), F (0.5 mg/L), Cl (169 mg/L), and Sulfate (263 mg/L). It is estimated that 5.6% of the population of this township are highly exposed to nitrate, 79.1% to fluoride and 13.5% are exposed to sodium. The average WQI in Rey Township in a good spectrum is 71.22.
Conclusion: 17 samples (23.2%) were assessed in excellent spectrum, 54 samples (74%) in good and 1 sample (1.4%) in very poor spectrum and 1 sample in unsuitable condition were assessed. No sample was assessed in poor situation. The samples of the autumn showed the worst quality.
A Beiki, M Yunesian, R Nabizadeh, R Saeedi, L Sori, M Abtahi,
Volume 9, Issue 1 (6-2016)
Abstract
Background and objectives: Swimming is one of the most popular sport fields and entertainments that has considerable benefits for human health, but on the other hand microbial water contamination in swimming pools through transmission and spread of infectious diseases is a significant threat against public health. In this study, microbial water quality of all public swimming pools in Tehran were assessed and effective factors on microbial water quality were analyzed.
Materials and Methods: This cross-sectional study with the analytical approach was performed in 2013. The whole public swimming pools in Tehran were inspected and water samples were taken for measurement of microbial indicators including thermotolerant coliforms, heterotrophic plate count (HPC), and physicochemical parameters affecting the microbial water quality including turbidity, free residual chlorine and pH and an integrated swimming pool microbial water quality index were used to describe the overall situation. Operational parameters with probable effects on microbial water quality were checked through inspection using a checklist.
Results: The assessment of the swimming pool microbial water quality indicated that the compliance rates of thermotolerant coliforms and HPC were 91.4 and 84.5%, respectively. Compliance rates of free residual chlorine, turbidity, Ph, and temperature were also obtained to be 82.7, 45.5, 85.6, and 65.4% respectively. Based on the integrated swimming pool microbial water quality index, the proportions of swimming pools with excellent and good microbial water quality were 39.6 and 50.4% respectively and the others had not proper microbial water quality. The parameters of water free residual chlorine and turbidity, swimmer density, water recirculation period, dilution amount, cleaning, usage rates of shower and disinfection basin and operation of water treatment systems had significant effects on the microbial indicators (P<0.05).
Conclusion: The study showed that the overall microbial water quality status of public swimming pools in Tehran was acceptable and analysis of the results determined the most efficient interventions for improvement of the microbial water quality of the pools.
M Asghari, R Nabizadeh, H Norzad, H Mortezaee,
Volume 9, Issue 3 (12-2016)
Abstract
Background and Objective: Increasing air pollution and consequently adversely effects on the quality of life for many people has resulted in the use of the air quality indice for determination of the actual amount of pollutants and air quality, as one of the most important and effective measures for air quality control, to be considered further. The air quality health index (AQHI) is a new index related to air pollution developed in collaboration with Environment Canada and Health Canada, in 2001. The purpose of this study was to design and develop a software system for calculating AQHI for the first time in the country that calculates the health effects caused by the presence of several pollutants (NO2, O3,PM10, and PM2.5) at the same time with a new approach.
Materials and Methods: To achieve those aims, the software was designed and coded in Visual Basic. Net. After preparation of the software, it was tested using the real-time database of six air pollution monitoring stations in Tehran including Aghdasyeh, Setad Bohran, Shahrdari 4, Golbarg, Park-e- Roz, and Shahrdari 11.
Results: This program is a software package installed on the computer with the possibility of exporting Excel file. The performance of software testing was verified using real data.
Conclusion: The results of the verification tests show that the index calculated by the software introduced and presented in this study can be used as a useful tool to assess air quality.
A Gholampour, Ms Hassanvand, R Nabizadeh, Z Alizadeh, Ah Mahvi,
Volume 9, Issue 3 (12-2016)
Abstract
Background and Objective: The present study was carried out to determine the amount and ionic characterization of TSP and PM10 aimed at identifying the potential emission sources of particulates in the ambient air of Tabriz.
Materials and Methods: TSP and PM10 samples were collected by two high volume samplers during September 2013 to August 2014. Water-soluble ions in particulate matter were extracted using ultrasonic method and were identified by ion chromatography. Using Stata12 software, linear regression analysis was performed between the ions to determination of the major ionic component of the particulates. In addition, in order to identify the potential emission sources of PM10, the rotation varimax model was used.
Results: Total measured water-soluble ions in TSP and PM10 of the urban sampling site were 20.33±20.77 and 16.04±14.08 µg/m3, respectively. Among all detected ions, sulfate (8.69±5.79 µg/m3) and nitrate (8.47±7.9 µg/m3) were the dominant constituents followed by calcium and sodium.
Conclusion: The modeling results revealed that the soils of surrounding ground together with secondary PM and also resuspension of PM from polluted soil account for 80 percent of PM10 mass.
A Koolivand, K Naddafi, R Nabizadeh, A Jonidi Jafari, M Yunesian, K Yaghmaiean, S Naseri,
Volume 9, Issue 3 (12-2016)
Abstract
Background and Objective: The performance of in-vessel composting process, as one of the most effective methods of oily sludge treatment, depends on factors such as nutrients and temperature. Therefore, it is crucial to investigate the trend of changes of these factors. The aim of the present study was to investigate the trend of changes of organic carbon, nitrogen, phosphorus, and temperature during the composting of bottom sludge of crude oil storage tanks.
Materials and Methods: The sludge was mixed with the immature compost at the various ratios of sludge to compost including 1:2, 1:4, 1:6, 1:8, and 1:10 with the initial C/N/P of 100/5/1 and then was composted for a period of 10 weeks. The process of mixing and moisture adjustment of the mixtures was done 3 times a day during the composting period. Sampling and analysis were performed every week for organic carbon, nitrogen, and phosphorus and every day for temperature.
Results: The research indicated that the concentrations of organic carbon, nitrogen, and phosphorus were decreased sharply during the first weeks of the process and then they were decreased gently. At the final stage of the composting, the ratios of C/N and C/P increased from 20:1 and 100:1 to 26:1 and 166:1, respectively. In addition, the temperature of the reactors was kept in the mesophilic range during the process period.
Conclusion: The similar trend of decrease of organic carbon, nitrogen, and phosphorus in the composting reactors is an indication of decreasing the activity of the microorganisms involved in petroleum hydrocarbons degradation.
R Nabizadeh Nodehi, Ar Mesdaghinia, S Nasseri, M Hadi, H Soleimani, P Bahmani,
Volume 9, Issue 4 (3-2017)
Abstract
Background and Objective: Water corrosion and scaling are known as destructive phenomenon of drinking water quality and water facilities. In this study, the groundwater tendency to corrosion or scaling in source water, water storage reservoirs and distribution system were studied. Simultaneous use of some qualitative and a quantitative index along with statistical analyses to assess the water scaling or corrosion tendency were investigated.
Materials and Methods: The data analysis of groundwater, water storage reservoirs and water distribution system in rural area of Kurdistan province were analyzed and the amount of Langelier (LI), Ryznar (RY), Pockorius (PSI) and Larson–Skold (LS) and CCPP indices were determined. Corrosion and scaling threshold for qualitative indices were determined based on CCPP index. The mean of indices was compared with the thresholds using independent t-test. ANOVA was used to assess the difference between the indices in different sources of water.
Results: The balance range for LI, RY and PSI found to be -0.1-0.05, 7-9 and 7.1-8.5. The mean CCPP for groundwater, reservoirs and networks were 9.27 ± 1.29, 9.13 ± 1.25, 11.25 ± 1.23, respectively. All three sources of water have some tendencies toward scaling; however, a significant balance status was confirmed statistically. According to Larson–Skold index, sulfate and chloride anions did not play a role in scaling process.
Conclusion: The use of qualitative indices with CCPP index can provide more accurate estimation of water tendency toward scaling or corrosion. The assessment of qualitative indices along with CCPP is recommended in drinking water corrosion monitoring studies.
K Naddafi, M Yunesian, S Faridi, A Rafiee, S Parmy, Gh Safari, R Nabizadeh Nodehi , K Yaghmaeian, N Rastkari, R Ahmadkhaniha, S Niazi, M Hoseini,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Polycyclic aromatic hydrocarbons (PAHs) are a group of organic pollutants that are mostly generated during the incomplete combustion. The main objective of this study was to characterize potential sources of PAHs in Tehran.
Materials and Methods:, Samples of PM10 were collected at 10 monitoring stations belonging to Tehran Air Quality Control Company (AQCC) and transferred to laboratory for analysis. Besides, a SKC Flite 2 Air Sampling Pump (SKC, USA) equipped with a sampling head and PM10 size-selective inlet was used at four stations to compare the results obtained by collecting AQCC monitors (AQCCMs) tapes with the standard sampling procedures for assessing the interchangeability of two field sampling methods. The principal component analysis (PCA) and diagnostic ratios were applied to identify emission sources and source contribution.
Results: The average diagnostic ratios of phenanthrene (Phe)/ (Phe+anthracene (Ant)), benzo(a)anthracene (BaA)/ (BaA+chrysene (Chry)), fluorantene(Flu)/ (Flu+pyrene (Py)), and indeno(1,2,3cd) pyrene (IcP)/(IcP+benzo(ghi)perylene (BghiP)) in samples were 0.79, 0.52, 0.43 and 0.38, respectively. These ratios showed that the combustion, especially fossil fuels and motor vehicles, was the main sources of PAHs emission in Tehran. The results of PCA analysis also indicated that 49, 29 and 22% of PAHs sources in Tehran atmosphere were attributed to gasoline-driven vehicles, diesel vehicles and other sources, respectively.
Conclusion: According to the results, the combustion, especially fossil fuel and motor vehicle, was the main sources of PAHs emission in Tehran.
M Heydari, R Nabizadeh Nodehi, M Ali Mohammadi, K Yaghmaeian,
Volume 10, Issue 1 (6-2017)
Abstract
Background and Objective: Bottled water consumption is rapidly increasing in recent years for various reasons.The main aim of this study was to survey the geological origin of Iranian bottled water and determine compliance or lack of compliance with the experimental data obtained through sampling 71 brands of drinking bottled water and mineral water.
Materials and Methods: In this study the coordinates of access points as a georef of the chosen points were launched on the "Iran geological map" and "Iran mineral and warm water map." The compliance of laboratory data and water types with the geological data were evaluated and compared with the important ionic ratios of the extracted water through using awh software.
Results: In examining 71 brands of the bottled water, 28% of the brands did not agree with the laboratory results, reflected by observing higher levels of bicarbonate in 50% of the bottled waters than those of the geological data.. Additionally, 70% of water types were calcic bicarbonate. In the bottled waters from North Alborz range with coastal Time deposits around the Caspian Sea, there was a source of brine or sea water that was about 55% of this amount.
Conclusion: Water pass through different geological structures and the dissolution phenomenon might be an important factor for the observed disagreement. Because chemical treatment and use of additives on mineral waters are not allowed it prompts further studies to determine the cause and origin of this issue through sampling from the factory and water source.
