Health and environment
Mostafa Sobhanikia; Edris Bazrafshan; Hossein Kamani
Volume 24, Issue 2 , May and June 2017, , Pages 144-137
Abstract
Backgrounds and Objectives: Antibiotics can’t be removedefficiently by conventional wastewater treatment.Nano Zero Valent Iron (nZVI) has high efficiency of degradation of contaminants such as heavy metal, nitro aromatic compounds and insecticides. Ozonation is one of the most well known methods ...
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Backgrounds and Objectives: Antibiotics can’t be removedefficiently by conventional wastewater treatment.Nano Zero Valent Iron (nZVI) has high efficiency of degradation of contaminants such as heavy metal, nitro aromatic compounds and insecticides. Ozonation is one of the most well known methods for remove of chemichal-resistant materials like antibiotics of water and wastewater
Materials and Methods: This study is experimental. nZVI and ozonation were used to remove of penicillin G. for determination removal efficiency of penicillin, COD and TOC, factors: initial pH, dose of nano particle, initial penicillin dose, reaction time with nano particle and ozone were investigated.
Results: Removal efficiency of penicillin G, COD, TOC in stage of reaction with nZVI were 96.35%, 73.13% and 47.45%, respectivly with reaction time: 60 min, initial penicillin concentration: 100 mg/L, COD: 1429 mg/L, TOC: 510 mg/L, pH=7, nano particle iron concentration: 0.25 g/L. In the stage of reaction with ozone, removal efficiency of penicillin G, COD and TOC were 99.5%, 96.35% and 92.65%, respectivly with reaction time: 13 min, pH=9, initial penicillin 20 mg/l, COD: 356 mg/L, TOC: 136 mg/L, volumetric flow rate of ozone: 5 L/min.
Conclusion:The best removal efficiency in stage of nano particles reaction was in pH=7, initial nZVI concentration 0.25 g/L, initial penicillin concentration 100 mg/L and time about 60 min. The best removal efficiency in stage of ozonation was in pH=7 and time about 9 min.
Somayyeh Rahimi; Mostafa Alizadeh; Ferdows Kord Mostafapour; Edris Bazrafshan; Edris Hosseinzadeh; Mahmoud Taghavi
Volume 23, Issue 1 , May and June 2016, , Pages 48-57
Abstract
Background & Objectives: With increasing the dairy products, particularly cheese, the problem of pollution arisen from the corresponding wastewaters and their treatment is being more serious than before. One of the used treatment methods for such wastewaters is coagulation process. This study was ...
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Background & Objectives: With increasing the dairy products, particularly cheese, the problem of pollution arisen from the corresponding wastewaters and their treatment is being more serious than before. One of the used treatment methods for such wastewaters is coagulation process. This study was done with the aim of determining optimal condition of coagulation process for dairy wastewater treatment using poly Aluminium chloride (PAC). Materials & Methods: At first, the coagulation process with PAC coagulant was used under laboratory conditions. By changing important parameters affecting the system pH (2-12) and coagulant dosage (5-100 mg/L), the decreasing of quality parameters of effluent such as Chemical Oxygen Demand(COD), Biological Oxygen Demand(BOD), Total Kjehldahl nitrogen (TKN), Total Phosphorous(TP) and Total Dissolved Solids (TDS) were obtained. Results: Experiments showed the removal efficiency ofCOD, BOD, TKN, TP, and TDS in pH 8 and coagulant dosage of 50 mg/L at 22±2 °C can be reached to 74.51, 84.81, 68.24, 65.46 and 85.69, respectively, which were the highest amounts among the pHs and coagulant dosages studied. Conclusion: The results showed that PAC coagulant is able to improve quality parameters of dairy wastewaters to standard levels. Because of availability, easy operation and acceptable removal efficiency for this wastewater type, PAC coagulant can be used for treatment of dairy industries wastewater.
Edris Bazrafshan; Khosro Afsari; Nayereh Pormolaee; Mohammadali Forghani; Hamideh Khedengi; Hamideh Kord Mostafapor
Volume 22, Issue 1 , March and April 2015, , Pages 73-83
Abstract
Introduction: At present time, dental solid waste management continues to be a major challenge, particularly in most healthcare facilities of the developing world such as Iran. In this country, few studies have been conducted on dental solid waste management and its composition. In this study, hazardous ...
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Introduction: At present time, dental solid waste management continues to be a major challenge, particularly in most healthcare facilities of the developing world such as Iran. In this country, few studies have been conducted on dental solid waste management and its composition. In this study, hazardous status of dental solid waste, which has a significant role in cross-infection chain, was studied.
Materials & methods: This work is a descriptive and cross sectional study which was performed during 2013-2014. For this research, 159 publicand private dental centers in Sistan and Baluchestan province were selected and both the composition and generation rate of dental solid waste were measured. Dental solid wastes were categorized to four main categories including domestic type, potentially infectious, chemical and pharmaceutical and toxic wastes and, finally, they were analysed.
Results: The results showed that the percent of potentially infectious, domestic type, chemical and pharmaceutical and toxic wastes were 80.3, 11.7, 6.3 and 1.7%, respectively. Also, the results indicated that the dental solid waste generation rate for total waste, potentially infectious, chemical and pharmaceutical waste, domestic type and toxic waste was 169.9, 153.3, 11.2,8.6 and 3.3 g per patient per day (g/p.d), respectively. Additionally, the generation rate of dental solid waste for total waste, domestic type, potentially infectious, chemical and pharmaceutical and toxic waste was 194.5, 22.6, 156.1, 12.3 and 3.4 kg/day, respectively.
Discussion: For the best management of dental solid waste, it is suggested that source reduction, separation, reuse and recycling programs be implemented and each section of dental waste be collected and disposed separately, in agreement with related standards.
Ferdovs Kord MostafaPor; Edris Bazrafshan; Farnaz Heidar Nejad
Volume 20, Issue 2 , May and June 2013, , Pages 142-153
Abstract
Background: Phenol is one of the main components concerned in the industrial wastewater. Physicochemical or conventional biological methods are usually used for the treatment of wastewater with high concentrations of phenol. At present study, the adsorption potential of phenol from aqueous solutions ...
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Background: Phenol is one of the main components concerned in the industrial wastewater. Physicochemical or conventional biological methods are usually used for the treatment of wastewater with high concentrations of phenol. At present study, the adsorption potential of phenol from aqueous solutions by Pistachio hull ash was investigated.
Materials and methods: Present study is an experimental survey that was performed in a batch system. To study the efficiency of Pistachio hull ash in phenol removal from aqueous solutions, the effect of critical variables such as contact time (15, 30, 45, 60, 75, 90, 105 and 120 min), initial phenol concentration (5, 10, 20, 30, 40, 50 and 100 mg/L), adsorbent dosage (0.1, 0.2, 0.3, 0.4, 0.5 and 0.6 g/L) and initial pH of solution (2,3,4,5,6,7,8,9,10,11,12,13) was investigated.
Results: Maximum adsorption capacity of the Pistachio hull ash was 327.6 mg/g at pH 5, initial concentration of 100 mg/L and reaction time 45 min, which 98.28% of the phenol was removed. The adsorption equilibriums were analyzed by Langmuir and Freundlich isotherm models. It was found that the data fitted to Freundlich (R2=0.9436) better than Langmuir (R2=0.8395) model.
Conclusion: According to achieved results, it was observed that Pistachio hull not only was an inexpensive absorbent, but also a quite effective factor in removal of phenol from water and wastewater.