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Showing 4 results for Processing

M Moradzadeh, Kh Ashrafi, M Shafiepourmotlagh,
Volume 11, Issue 4 (3-2019)
Abstract

Background and Objective: Hydrocarbon processing industries are considered as potential sources of volatile organic compounds (VOCs) due to their specific nature. These compounds can directly or indirectly through producing secondary pollutants have adverse effects on the health of individuals. Therefore, identification of them is an important step in the formulation of control programs. This study aimed to identify the type and amount of the most important volatile organic compounds in the South Pars region.
Materials and Methods: In this study, industrial processes located in the region were investigated and information was gathered for estimation of VOCs emissions. The emission was estimated over a one-year period and was ranked according to three criteria including emission, health hazards and ozone production potential.
Results: The results showed that the greatest emission was due to equipment leakage and storage tanks (64%), cooling towers (21%) and flaring (11%). The 171 VOCs were determined in Plum of these processes and propylene had the greatest contribution (21%). The alkenes had the highest share in total mass (41%) and ozone production (78%). By weighting the list based on the three criteria mentioned above, formaldehyde is the most important emitted VOC and the main sources of it were olefins and aromatic units.
Conclusion: This method can be a useful tool for identifying effective organic compounds in such areas. Here, the optimum control strategy is mitigating of emission of formaldehyde from the aromatic and olefins processes. The next priority is to control propylene, ethylene and butylene emission sources.
 

Somayeh Mokhtari, Mahdi Farzadkia, Leila Janani, Ahmad Jonidi Jafari,
Volume 13, Issue 2 (8-2020)
Abstract

Background and Objective: The purpose of this cross-sectional study is to evaluate the microbial contamination of food-handlers' hands and food contact surfaces in food preparation and distribution centers.
Materials and Methods: This study was performed in 2019 in Fardis city of Alborz province. In this study, 100 samples of food contact surfaces and 48 samples of staff hands were collected from three traditional bakery units, pastry centers and snack shops and the microbial load was determined using a luminometer device. The samples were then analyzed for the presence of coliforms, Escherichia coli and Staphylococcus aureus bacteria.
Results: Among the samples studied, 62 samples (62%) of contact surfaces and 27 samples (56.25%) of food-handlers' hands had microbial load more than 30 RLU.  According to the results, the main cause of microbial contamination of equipments were 44.40% of Coliform bacteria and 11.10% of Staphylococcus aureus on the equipment of confectionery centers,  10% of Escherichia coli, 20% of coliforms and 20% of Staphylococcus aureus were detected on food tools and 2.30% of Escherichia coli, 14% of coliforms and 14% of Staphylococcus aureus –on the tools of traditional bakeries.Moreover coliform bacteria was noticed onconfectionary-handlers' hands and all three types of bacteria were also found on the hands of bakers.
Conclusion: The results showed that the cleanliness of food contact surfaces and the personnel hands hygiene was in poor condition which may pose serious threat to public health. Therefore, adequate personal hygiene practices, food safety and inspections should be implemented to protect the health of society.

Alireza Rahimi, Nabi Shariatifar, Ali Heshmati,
Volume 14, Issue 3 (12-2021)
Abstract

Background and Objective: The Pesticides used in agriculture have caused great concern due to their adverse effects on human health. In this study, the effect of rinsing, crushing, filtering, clarifying with bentonite and pasteurization on the reduction of diazinon, ethion and phosalone during Asari grape juice was investigated.
Materials and Methods: Vineyard was sprayed during three growth stages before flowering, sour grape (ghooreh) and during grape ripening with phosalone, diazinon, ethion and in doses of 525, 600, 750 g of active substance per hectare, respectively. Twenty-four hours after the last spraying step, the grape sample was harvested and exposed to the process of rinsing (20-30 s), crushing, filtering, clarifying and pasteurizing. Then, the pesticides residue concentration was determined after each step by GC-MS/MS.
Results: The initial concentrations of diazinon, ethion and phosalone in unprocessed grape samples were 0.640, 0.716 and 0.550 mg/kg, respectively. The reduction values of diazinon during the juicing processes of rinsing, crushing, filtering, clarifying with bentonite and pasteurization, in comparison with the concentration of unprocessed grapes, were 25.72, 41.96, 74.54, 90.21 and 100% (not found), respectively; while these values were 9.78, 28.50, 69.45, 89.38 and 96.74% for ethion and 17.32, 28.47, 46.40, 80.25, 93.28% for phosalone, respectively. All processes significantly reduced insecticides residue.
Conclusion: Findings showed that the processes of grape juice production could significantly decrease the diazinon, ethion and phosalone residues.

Sadaf Moeini, Seyed Masoud Monavari, Fariba Zamani Hargolani,
Volume 17, Issue 2 (9-2024)
Abstract

Background and Objective: The increase in waste at integrated urban waste centers, along with the problems and adverse environmental consequences due to their inappropriate establishment have become more apparent. This research was conducted with the aim of determining and investigating environmental pollution in urban waste integration management centers.
Materials and Methods: This research investigated the environmental pollutants in the integrated waste center in Koohak at various distances ranging from 0 to 900 meters. Four main criteriawaste, water pollution, air pollution and sound pollutionwere determined, each with 16 sub-criteria. The map of each criterion and sub-criteria were multiplied by the coefficients they received from the weights obtained using the Analytical Network Process (ANP) method. By combining the criteria using the Weighted Linear Combination (WLC) method and superimposing them, finally, the studied area was ultimately classified into three classes: inappropriate, medium, and suitable.
Results: Air pollution, with a weight of 0.26, had the highest rating compared to the other three criteria. Noise pollution (0.25), water pollution (0.24) and waste-related criteria (0.23) were ranked next. The results of the Kruskal-Wallis test indicated a significant difference in pollutant concentrations between different stations (p<0.05). Additionally, the results show that the average concentration of pollutants at distances of 0-300 meters differed significantly from those at all other distances (p<0.05). After determining the suitable zones using the WLC method, the results showed that 62.5 percent of the criteria were approved by the environmental organization.
Conclusion: By examining the results of the methods used in this research, it can be concluded that the combination of ANP and WLC methods provide effectivee results. However, uncertainty in subjective decisions and time constraints in decision-making have posed challenges in assessing waste collection in integrated urban waste centers.
 


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