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Showing 7 results for Amiri
Investigation of TOC Removal from IndustrialWastewaters using Electrocoagulation Process
M Ahmadimoghadam, H Amiri,
Volume 3, Issue 2 (6 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.


Carcinogenic and Non-carcinogenic Risk Assessment of DDT and its Metabolites Residuals in Pasteurized Milk in General Population of Tehran
Ar Khajeamiri, M Zare Jeddi, R Ahmadkhaniha, N Rastkari,
Volume 9, Issue 3 (12-2016)
Abstract

Background and Objective: Organochlorine pesticides are among the endocrine disrupting chemicals believed to produce a wide variety of adverse health outcomes such as cancers. Generally, fatty foods of animal origin are the major sources of human exposure to lipophilic contaminants such as DDTs and their metabolites. The objectives of the present study were to evaluate exposure of general population to DDTs via dietary milk consumption in Iran, and to assess the respective potential risks to health of people in terms of carcinogenic and none-carcinogenic effects.

Materials and Methods: The DDT residue levels were determined by GC/MS analysis in 60 milk samples of full fat pasteurized commercial types (3% fat). The assessment of carcinogenic and non-carcinogenic risks was calculated through international standard methods.

Results: In all of the milk samples, DDT and its metabolites were detected in the range of 0.0015 to 0.28 µg/L with the mean of 0.05±0.03, 0.15±0.08, 0.09±0.05, 0.05±0.02 µg/L for o, p-DDE, p,p-DDE, p,p-DDT, p,p-DDD, respectively. The calculated estimated daily intake (0.00006-0.0002 mg/kg/day) for all categories and all compounds were lower than the Reference doses (RfDs). Consequently, the hazard quotients calculated in these groups for DDTs were less than 1. Hazard index obtained for all compounds in full fat pasteurized milk based on maximum DDT residue concentrations was higher than unity confirming health risk. From the carcinogenic point of view, there is no risk and it was within the acceptable threshold of EPA.

Conclusion: The results of the present study showed that the general population are exposing to DDT and its metabolites constantly. Therefore, it is recommended to biomonitoring and measuring these chemicals in all age groups especially in children. 


Optimization of UV/H2O2/TiO2 process for the treatment of hospital effluent
M Hadi, M Solaimany Aminabad, M Amiri, M Arjipour,
Volume 11, Issue 3 (12-2018)
Abstract
Background and Objective: Treatment of hospital wastewaters has an important role in reducing the discharge of organics and pharmaceutical compounds into aquatic environments. Nowadays, advanced oxidation processes were extensively used for the removal of organic compounds from treated effluents. The study aimed to examine organic compounds removal from real treated effluent of a hospital treatment plant using a lab scale UV/H2O2/TiO2 process by optimizing the process.
Materials and Methods: The effluent characteristics including COD, TOC and DOC were measured and recorded. A hybrid advanced oxidation process (UV/H2O2/TiO2) was used for the removal of organic compounds. The experiments were designed using surface response methodology (RSM). The effects of the independent factors including pH, duration of UV irradiation, H2O2 and TiO2 concentrations on COD, TOC, DOC and the approximate cost of treatment were assessed by analysis of variance (ANOVA).
Results: The optimal condition was 7.2 for pH, 50 mg/L for H2O2, 100 mg/L for TiO2 and 19.65 min for irradiation time. This condition provided the maximum removal percentage for organic compounds with a minimum cost. The removal efficiency for TOC, DOC and COD were 63.9, 52.9, and 64.7%, respectively. The treatment cost was approximated to be $ 0.71 per one liter of the effluent.
Conclusion: Irradiation and H2O2 concentration had the greatest impact on the cost of the treatment. UV/H2O2/TiO2 process seems to be an expensive process for tertiary treatment of wastewater. However, further investigations are required to evaluate the cost effectiveness of the process for a full scale operation.
 
 

Potential health risk assessment of heavy metals (Cu, Zn, Ni) via the consumption of the prevailing bony fish Liza auratas (Risso, 1810) of Caspian Sea
Z Farahbakhsh, A Akbarzadeh, P Amiri, A Naji,
Volume 12, Issue 2 (9-2019)
Abstract
Background and Objective: Heavy metals enter to water resources through various ways, causing dangers such as illness, cancer, and, in general, a disorder in the body of living organisms. Mullet (Liza aurata) is highly consumed by the people living in Guilan province, Iran. Therefore, the amount of heavy metals included copper, zinc, and nickel was investigated in the muscle tissue of mullet.
Materials and Methods: A total number of 11 mullet were obtained from Bandar Anzali.  After a preparation step, the fish samples were digested using chemical digestion, and the amounts of heavy metals were determined by atomic absorption.
Results: The average concentration of copper, zinc, and nickel in muscle tissue was 10.07±0.93, 28.39 ±3.99, and 4.01 ± 0.55 μg/g dry weight, respectively. The concentrations of the studied metals were lower than the FAO, WHO, FDA, NHMRC and UKMAFF international standards, except for the nickel. The daily absorption rates of the studied metals (EDI) for children and adults were lower than the reference dose set by the EPA and the TI provided by the FAO / WHO Organization. The risk potential (THQ) of seven days, three days and one day consumption per week of Golden grey mullet for both adults and children were found less than 1. The hazard index (HI) of 7 days a week consumption of mullet for children was greater than 1.
Conclusion: According to the results of the present study, the consumption of this fish has a harmful effect on consumer health in children age group.
 

Effect of irrigation with treated wastewater on lead and cadmium accumulations in soil and sweet pepper plant
Maliha Afkhami, Fazel Amiri, Tayebeh Tabatabaie,
Volume 14, Issue 1 (5-2021)
Abstract
Background and Objective: Limited water resources in arid and semi-arid regions are one of the major limiting factors in agricultural production. Thus, unconventional water resources, such as urban treated wastewater, may be used for irrigation. Application of wastewater to the soil may cause accumulation of heavy metals (HMs). Soil pollution causes uptake of these metals by plants and their entrance to the food chain. In the present greenhouse research, concentration variations of HMs (lead (Pb) and cadmium (Cd)( in soil and sweet pepper (Capsicum annuum) plant were investigated.
Materials and Methods: The experiment was conducted as a completely randomized design with three replications and irrigation with different wastewater treated (well water, wastewater treatment and diluted wastewater). To evaluate the effects of different irrigation treatments on soil, parameters of acidity (pH), electrical conductivity (EC), the concentration of heavy metals Pb and Cd in soil were studied.  Additionally, for the effects of irrigation treatments on sweet pepper plant, parameters of biomass weight, fresh and dry weight and Pb and Cd concentrations (in branches, fruits and roots) were measured. The amount of Pb and Cd in the pepper were measured by ICP-OES. The obtained average concentrations were compared using one-way analysis of variance (ANOVA), and the Duncan test was used to determine the differences between groups (p <0.05). The independent t-test was also used to investigate the difference in concentrations of Pb and Cd in soil and water (p <0.05).
Results: The results of chemical analysis of soil and pepper showed that irrigation with wastewater did not cause a significant increase in the concentration of Pb and Cd in the soil and in the branches, fruits and roots of the pepper. The concentration of Pb and Cd in the soil and in the branches, fruits and roots of the pepper was within the allowable and standard concentration range. The difference in lead and cadmium concentrations in the soil before planting was not significant; however, at the end of the study period, the Pb concentration in pepper was higher than the Cd concentration. The use of wastewater increased the fresh and dry weight of branches, fruits and roots of the pepper.
Conclusion: The results showed that Pb and Cd concentration in roots and aerial parts of pepper plant was not increased significantly as a result of wastewater irrigation (p <0.05). The results of this study are limited to one growing season and by the continued use of municipal wastewater, the concentration of Pb and Cd in the soil and then in the plant may exceed the standard. Especially in the case of Pb, which seems to have shown a slight tendency to increase relative to the primary soil and the pepper. Therefore, the continuation of this study is recommended to evaluate the long-term effects of Bushehr municipal treated wastewater on the concentration of heavy elements in soil and plants, and soil properties. Overall, it should be acknowledged that based on technical recommendations, the use of treated wastewater are not recommended.

Evaluating the efficiency of a baffled-filter system with sponge media on removal of turbidity, microbial agents, and total organic carbon from water
Zahra Amirilagmuj, Gholamreza Moussavi,
Volume 14, Issue 2 (9-2021)
Abstract
Background and Objective: Access to safe water is critical for protecting human health. Turbidity is one of the main physical parameters that affect the quality of water from both health and aesthetical points of view. Therefore, waters should be treated based on the standards set for turbidity before consumption. This study was performed to determine the performance of a bench-scale baffled filter system for removing the turbidity, microbial population, and total organic carbon (TOC) from the contaminated water.
Materials and Methods:  A lab-scale Plexiglas baffled filter consisting of five compartments with a total working volume of 2 L was designed and constructed. The polyurethane foam cubes were used as filter media. The effect of turbidity (10, 50, and 100 NTU) and surface overflow rate (SOR: 7.5, 10 and 15 m/h) was investigated on the performance of the developed system.
Results: A direct relationship between turbidity, TOC, and microbial density was observed in the inlet water. The efficiency of the baffled filter in the removal of turbidity and the period of the filter operation run both enhanced as the SOR was either decreased or the inlet turbidity was increased. In addition, almost complete removal of TOC from the inlet water was noticed.
Conclusion: The results of the present study indicated that the baffled filter system with sponge media can be a novel and effective method for the removal of turbidity, microbial contaminants and TOC from the natural surface water.

Investigating the effect of micro aerobic process on the efficiency of anaerobic digester of sulfate-rich municipal sewage sludge
Abbas Ali Moserzadeh, Gholamreza Nabi Bidhendi, Nasser Mehrdadi, Mohammad Javad Amiri,
Volume 17, Issue 1 (6-2024)
Abstract
Background and Objective: A high concentration of Hydrogen Sulfide in biogas is a major problem associated with anaerobic digestion of waste rich in sulfate. It disrupts the functional process and reduces the lifespan of biogas facilities. The micro-aerobic (MA) process is an alternative method for direct sulfurization.
Materials and Methods: The effect of sulfate loading (200, 500 and 700 mg/L) on H2S in biogas were investigated. Subsequently, the effect of MA process (0.88, 1.04, 1.34 NL/day) on H2S reduction in biogas production was evaluated. Additionally, oxidation-reduction potential (ORP) and pH were measured. Finally, under optimal conditions, the biogas volume and the content of CH4 and CO2 in biogas were determined.
Results: The results indicated that there were no significant differences in biogas volume production between the reactor fed with 200 mg/L sulfate and the control. However, the biogas production in reactors with 500 and 700 mg/L sulfate decreased to 4103 and 3929 mL, respectively. The H2S levels in control and reactors with 200, 500, 700 mg/L sulfate were 0.35, 0.46, 2.4, and 1.8%, respectively. In reactors with MA at rates of 0, 0.88, 1.04, 1.34 NL/day, the H2S levels were 1.95%, 0.9%, 0.4% and 0.1% (V/V) in biogas, respectively. The pH in reactor varied between 2.7 and 4.7, and the ORP was measured between -281 and -291 mV. Statistical analysis shows that no significant difference was observed between the average daily production of biogas with MA process of 0.88 and 1.04 NL/day. However, MA with 1.34 NL/day resulted in a decrease in biogas production.
Conclusion: The results indicated MA at a rate of 1.04 NL/day is a favorable option for the treatment of sulfate-rich urban wastewater sludge due to its efficiency in H2S removal.
 

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