Showing 6 results for Nabizadeh
R Nabizadeh Noudehi , F Fakheri Raouf , N Jafarzadeh Hagigi Fard , M Monavari ,
Volume 4, Issue 4 (4 2006)
Abstract
Background and Aim: The Razi Petrochemical Complex is one of the greatest factories producing nitrogen and phosphate fertilizers and various other chemicals. The site, comprising 17 production units with a total surface area of around 100 hectares, is located on the outskirts of Imam Khomeini port. The ammonia (1) section of the plant, with its production capacity of 1000 tons/year, was selected as the setting for this research on the feasibility of waste minimization programs.
Material and Methods: This study was conducted form October 2003 to May 2005, and it involved more than 20 visits to the site to gather data. We covered areas such as quality and quantity of liquid waste, reasons for waste generation and the production period. We also studied the current system of waste management. The materials were subsequently classified according to method proposed by the United Nations. Finally, strategies were proposed to minimize waste production.
Results: Results showed that the unit produced 305509.38 cubic meters of liquid waste annually, and water used for cooling accounted for 62.35% of the total volume. The main reasons for the production of liquid waste were problems with the production. Over 95% of the waste was produced on a permanent basis. After classification, it emerged that 18.02% of the material was dangerous. Currently, 85.65% of the liquid waste in this factory is disposed of in the surrounding environment, and 14.35% is recycled.
Conclusion: The proposed strategies for minimizing the liquid waste production materials in the factory are: recycling and re-use (95%), production process modifications (4.79%), and volume reduction (0.01%). With the use of waste minimization methods, we can avoid the dumping of huge amounts of waste into the environment, reduce the loss of raw material, and make out a strong case for the efficiency of waste minimization efforts.
R Saeedi , K Naddafi , R Nabizadeh ,
Volume 5, Issue 2 (3 2007)
Abstract
Background and Aim:We studied the biosorption of lead(II) and cadmium(II) from aqueous solutions by the brown algae Sargassum sp. biomass in a batch system.
The heavy metal uptake was quite rapid, reaching 88-96% of the equilibrium capacity of biosorption in 15 minutes.
Material and Methods: Kinetic data were analyzed using the pseudo first-order, pseudo second-order, and saturation and second-order rate equations.
Results: The pseudo second-order and saturation rate equations gave the best fit with the experimental data(R2 > 0.99). The data obtained from experiments of single-component biosorption isotherm were analyzed using the Freundlich, Langmuir, Freundlich-Langmuir and Redlich-Peterson isotherm models. The Redlich-Peterson equation was found to provide the best fit with the experimental data (R2 > 0.99). Also the other models described the isotherm of lead(II) and cadmium(II) biosorption with relatively high correlation coefficients (R2 > 0.93).
Conclusion: Using the Langmuir model, the maximum uptake capacities (qm) of Sargassum sp. for Pb2+ and Cd2+ were 1.70 and 1.02mmolg-1, respectively.
A Gholampour , A.r Mesdaghinia , F Vaezi , R Nabizadeh , M Farrokhi , A Ghasri ,
Volume 5, Issue 2 (3 2007)
Abstract
Background and Aim: 2,4-Dichlorophenol (DCP) is a compound generated in a variety of industrial processes and also by chlorine disinfection of water polluted with phenolic compounds . Dumping of DCP into the environment and water resources is of great concern because of the compound's intense odor and toxicity. DCP is very soluble and resistant to biodegradability so it cannot be removed through conventional water and wastewater treatment processes. On the other hand, pollution prevention (P2) strategies have not been able to resolve the problem.
Material and methods: In this study, one of the AOPS named Fenton was used for DCP degradation. The method is based on simultaneous use of hydrogen peroxide and ferrous sulfate.
Results: Results of treatment with hydrogen peroxide and ferrous ion (as Fenton reagent ingredients) indicate that by oxidation of 50 mg/L DCP at 60 minutes contact time with iron concentration kept at 15 mg/L and various concentrations of H2O2 (50 and 100 mg/L), the efficiency of COD(Chemical Oxygen Demand) reduction would go up from 65% to 80% with higher concentrations of H2O2. We also determined the effect of various concentrations of ferrous ion on DCP oxidation rate. The results showed the prominent role of this ion in DCP treatment: increasing Fe concentration from 5 to 15mg/L produced a 60% reduction in COD occurred in 10 and 60 minutes contact times. Another conclusion was that the oxidation of DCP solutions by Fenton had a major effect on biodegradability so that BOD: COD ratios of these solutions increased significantly after this oxidation.
Conclusion: Pretreatment of waste containing dichlorophenol by the Fenton reagent can enhance the biodegradability of this chemical and perhaps of similar compounds in a short time interval.
R Nabizadeh, K Naddafi, M Mohebbi, M Yonesian, A.m Mirsepasi, S Oktaie, M Faghihi ,
Volume 5, Issue 4 (5 2008)
Abstract
Background and Aim: The scattered state of the rural populations- in terms of both the distance between villages and the distance between residential units within a single village- has made the task of supply, distribution and monitoring the quality of water a difficult one. In this study we looked at the bacteriological quality as well as access to safe potable water in selected villages of Tehran Province. This research started in February 2006 and ended in July the same year.
Materials and Methods: In this cross-sectional field study, sampling points were specified on the basis of the populations of the villages served by the Tehran Rural Water and Wastewater Company. After systematic sampling, the specimens were transferred to the laboratory for testing. Data were analyzed using the SPSS and Microsoft Excel software packages.
Results: Drinking water contamination with E. coli was observed in 5.99% of the villages. The degree of contamination was highest in the districts of Pakdasht, Savojblagh and Damavand, with rates of 33.34, 13.69 and 13.32 percent respectively. For 99.36% of the Tehran rural population the turbidity was lower than the standard value of 1053 set by the Iranian Institute of Standards and Industrial Research. Values in Savojblagh and Varamin were relatively higher, with rates of 96.51% and 99.30% respectively. Given the standard value of 1053, the residual chlorine levels were unacceptably low for 92.39% of the rural residents, with figures in the districts of Pakdasht, Damavand and Robatkarim reaching 75.67, 85.45 and 83.98 percent respectively.
Conclusion: Based on WHO guidelines concerning the microbial quality of water published in 2006, the average indicator for lack of E.coli in rural water of Tehran was 94.01%, i.e. at an excellent level. Levels were good for Damavand and Savojblagh, low in Pakdasht and excellent in all other districts.
A Mesdaghinia, H Nourmoradi, F Vaezi, S Naseri, R Nabizadeh, M Ali Mohammadi, Sh Nazmara,
Volume 6, Issue 2 (27 2008)
Abstract
Background and Aim: Methyl tertiary butyl ether (MTBE) is an oxygenated additive chemical added to gasoline, which is as a substitute for tetra ethyl lead, to reduce discharge of pollutants from automobile exhausts. This organic chemical is present in water samples collected from areas where gasoline wastes are abundant. The objective of this study was to investigate the possibility of MTBE removal from drinking water at the point of use (POU) by using an Iranian granulated active carbon (GAC) bed.
Materials and Methods: Adsorption of MTBE from drinking water at POU was studied by using an Iranian GAC bed. The water samples treated by this filter adsorber were prepared synthetically at two concentrations (50 ppb and 100 ppb). In addition, the effects of residual chlorine at concentrations of 0.2 and 0.5 mg/L and of chloroform at a concentration of 100 ppb on removal of MTBE were determined.
Results: It was found that this filter adsorber could treat 375 liters of water containing 50 ppb MTBE, 100 ppb chloroform and 0.2 ppm residual chorine. If the residual chlorine content was increased to 0.5 ppb, the volume of water treated would be 335 liters. The filter could t eat 195 liters of water containing 100 ppb MTBE, 100 ppb chloroform and 0.2 ppm residual chlorine to acceptable levels for drinking, provided the amount of MTBE is below the respective standard.
Conclusion: Both residual chlorine and chloroform reduced the MTBE adsorption capacity on GAC due to occupation of adsorption sites. In addition, to the tendency of GAC to adsorb chloroform and chlorine was greater than that of MTBE.
Mostafa Leili, Kazem Nadafi, Ramin Nabizadeh, Masoud Younesian, Alireza Mesdaghi Nia, Shahrokh Nazm Ara,
Volume 7, Issue 1 (23 2009)
Abstract
