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Mahdi Kargar, Amir Hossein Mahvi,
Volume 5, Issue 1 (6 2012)
Abstract

A MicrosoftInternetExplorer4 Backgrounds and Objectives: Large quantities of sludge are produced in biological wastewater treatment. Because this sludge is highly rotten, it should be stabilized before its disposal. Aerobic and anaerobic digestion is widely considered as stabilization techniques. Because of high retention time and sludge dewatering difficulties, reduction in retention time, operation and maintenance should be given into consideration. Ultrasonic process increases the enzymatic activity, so decreases the hydrolysis time, a limiting factor in digestion process, and contributes to the decrease of the detention time. The objective of this investigation is to determine the effect of ultrasound in improving dewatering and stabilization of aerobic and anaerobic digested sludge. In addition, the impact of ultrasonic treatment on improvement of sludge dewatering and aerobic and anaerobic digestion is compared.
Materials and Methods: In this survey, samples of aerobic and anaerobic digestion were collected from local full-scale Garb Town and Tehran South wastewater treatment plant, respectively. The grab samples were collected for 4 month from July to October 2010. Total numbers of 20 samples were collected biweekly for each type of digestion. Each sample was sonicated for 15, 30, 60, and 90 min under 35 and 131 kHz frequencies separately. Total solids, volatile solids , pH, temperature , total COD, dissolved COD and settle able solids were measured. Ultrasound bath of the solution in a 300 mL glass reactor was performed as a bath reactor with power of 500 W.
Result: The results showed that the application of ultrasonic wave increased dissolved COD and temperature and decreased volatile solid, pH and settle able solids. Application of ultrasonic wave with frequency of 131 kHz decreased the VS and increased the dewatering of sludge more effective than the 35 kHz frequency and the highest performance was at 15 min of time and 131 kHz of frequency. Also sonication method showed better efficiency for anaerobic sludge samples compared to the aerobic sludge samples.                 
Conclusion: The results obtained showed that digestion and dewatering properties of sludge improved by ultrasonic application. Therefore it can be used as an alternative method for the sludge treatment.

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P Atabakhsh, M Kargar, A Doosti,
Volume 12, Issue 2 (9-2019)
Abstract

Background and Objective: Human adenoviruses transmitted from contaminated water are one of the major pathogens that has been introduced as one of the most important new qualitative water indicators due to their resistance against the purification processes. The main objective of this study was to evaluate efficiency of human adenovirus removal in different units of Isfahan Water Treatment Plant.
Materials and Methods: Sampling was conducted from 5 points of a water treatment plant including raw water, clarifier, ozonation, filtration, and treated water for one year. Virosorb 1MDS electropositive cartridge filter was used for the concentration of water samples. To test the adenovirus antigens, enzyme-linked immunosorbent assay (ELISA) was employed. Real-time PCR and PCR were also employed for quantitative identification and genotyping, respectively. Moreover, total and fecal coliform and physicochemical parameters of the samples were measured.
Results: Out of the 60 samples examined, 12 (20%) samples were diagnosed with ELISA and 16 (26.67%) with molecular method. The highest number of adenoviruses detected in autumn was 7 (12%) in raw water influent, 6 (10%) in clarifier, and 3 (5%) samples in ozonation. The high frequency of adenovirus detection was in autumn (50%) and the lowest was in spring (12.5%). Furthermore, it was found that the total coliform in raw water influent was between 102-103 CFU/mL.
Conclusion: The results showed that the removal efficiency of adenovirus in filtration and disinfection units of the treatment plant was high and the filtration unit in the plant was an effective unit for the virus removal.
 

Jawad Kadhim Noor, Atefeh Chamani, Ahmed Najm Abdallh Al-Mosawy, Narges Kargari,
Volume 17, Issue 3 (12-2024)
Abstract

Background and Objective: The pollution of trace elements in urban soil has attracted wide attention due to its detrimental environmental and health effects. Therefore, this research was conducted to evaluate of the content, pollution levels, and health risks associated with trace elements (Fe, Zn, Pb, Cd, Cu, Mn, and Mo) in the surface soil of Al-Qasim City in Babylon Governate in 2024.
Materials and Methods: This descriptive cross-sectional study involved, a total of 50 surface soil samples from a depth of 0-20 cm. The elemental content of the samples was determined using inductively coupled plasma optical spectroscopy (ICP-OES). Additionally,, the enrichment factor (EF), pollution index (PI), pollution load index (PLI), hazard index (HI), and carcinogenic risk (CR) were calculated. Statistical data analyses were done using SPSS software. 
Results: The average concentrations of Fe, Zn, Cd, Cu, Mn, and Mo in the soil were 27240, 62.7, 0.302, 33.8, 570 and 0.999 mg/kg, respectively. The highest average concentrations of Fe (30,331 mg/kg), Cu (37.3 mg/kg), Mn (639 mg/kg), and Mo (1.08 mg/kg) were found in downtown areasm whilefor the highest concentrations of Zn (65.3 mg/kg) and Cd (0.332 mg/kg) were observed in rural and midtown areas.
Conclusion: The results of this research demonstrate the impact of urban activities—such astraffic, industry, and agriculture—on the trace element pollution in the soil of Al-Qasim City. Therefore, regular monitoring of trace element concentrations and identification of their pollution sources are recommended to reduce and manage associated environmental and health risks.
 


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