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Background: In this study, the effect of wastewater produced by pistachio processing in processing terminals on wastewater treatment plants with activated sludge process was investigated
Methods: The pilot of activated sludge was constructed at the laboratory scale similar to wastewater treatment plant in Kerman and it was investigated in different ratios of the wastewater of pistachio processing with urban wastewater and return sludge ratios of 50% and 75%. The best reactor efficiency in treating pistachio processing wastewater was obtained at a ratio of 5% with urban wastewater and return sludge of 50% plus 5 and 10% with urban wastewater and return sludge of 75%
Results: The removal efficiency in the reactor in the aforementioned ratios was obtained to be 96.9%, 98%, and 96.2% for COD, 95.7%, 97.2%, and 93.3% for BOD5, and 7.1%, 99%, and 96.97% for phenolic compounds, respectively. The removal efficiency of BOD5 and COD reduced with the increase in the ratios of pistachio processing wastewater especially with the presence of phenolic compounds. The one-way analysis of variance [ANOVA] indicated that in the aforementioned ratios of pistachio processing wastewater with urban wastewater, the mean COD and BOD5 in the output wastewater were significantly lower than the standards of Iranian environmental organization and guidelines of World Health Organization [WHO]
Conclusion: Activated sludge process is able to remove organic compounds of pistachio processing wastewater at a ratio of 5% and return sludge of 50% along with ratios of 5 and 10% and return sludge of 75% with urban wastewater with a high efficiency
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Background: Microalgal lipid is a promising feedstock for biodiesel production. The aim of the present study was to investigate the effects of cultivation temperature on the growth and lipid accumulation properties of Nannochloropsis oculata microalgae
Methods: Nannochloropsis oculatacan grow in a wide range of temperatures [5 -35°C]. Late in the stationary growth phase of microalgae, biomass production and lipid accumulation were measured. The methanol-chloroform extraction method was used to extract total lipids from dried cells. The direct esterification method was used to measure fatty acids. Constituents were identified by gas chromatography
Results: The results show that the maximum specific growth rate at 20°C was 0.1569 day[-1], and the maximum biomass production of microalgae at 25°C was 2.2667 g/L. The highest percentage of biomass conversion into lipid [35.71%] occurred at 30°C. Maximum lipid productivity was seen at temperatures of 15°C, 20°C, and 25°C, but the analysis of fatty acids in the three temperatures shownare maximum accumulations of triglycerides in the microalgae cells at 20°C and 25°C
Conclusion: In the cultivation of Nannochloropsis oculata, the optimal temperature range for maximum efficiency in biodiesel production from lipids is 20°C to 25°C
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Background: This study purposed to assess the health risks of heavy metals including nickel [Ni], chromium [Cr], mercury [Hg], and lead [Pb] in three widely-consumed fish from the coast of Bandar Abbas [Persian Gulf] and to determine the maximum amounts allowed for consumption according to the degree of contamination
Methods: This cross-sectional study was conducted in the summer and fall of 2013. Thunnus tonggol and Liza klunzingeri were selected from the Bandar Abbas market, and Pleuronectiformes were caught from the sea. Heavy metal concentrations were determined by atomic absorption. Risk assessment and allowable consumption levels were determined according to methods provided by the US Environmental Protection Agency [USEPA]
Results: The highest average levels of Ni and Cr in Thunnus tonggol were 0.059 and 0.234 [ micro g/g dry weight], respectively. The highest average level of Hg in Pleuronectiformes was 0.095 [ micro g/g dry weight], and the highest average level of Pb in Liza klunzingeri was 0.006 [micro g/g dry weight]. The target hazard quotient [THQ] for all analyses of metals in the studied species and the hazard index [HI] were less than 1 for all three species
Conclusion: The results showed that despite Ni, Cr, Hg, and Pb pollution, the consumption of up to 4 [kg/d] of Thunnus tonggol by adults and up to 2.2 [kg/d] by children does not cause health problems in terms of the tested heavy metals. For Liza klunzingeri, these levels are 7.32 and 4.02 [kg/d], respectively
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Background: bio-aerosols in the air of hospital wards have an important role in the development of infections. It is important to make quantitative and qualitative estimations of microorganisms in the air of these wards as an index for environmental hygiene applicable to different hospital wards. The aim of the study was to investigate degrees of diversity and density of bio-aerosols in the education hospitals of Kerman city
Methods: this study applied a descriptive-cross-sectional methodology in the second half of 2014 in the education hospitals of Kerman city, with bed capacity of over 300. As many as 200 samples were collected from the air in different wards of each hospital using the standard method of the National Occupational Health and Safety Institute. Following collection, samples were placed in an incubator for 48 hours and then bio-aerosol detections were made for and resulting data reported as colonies/m3
Results: results indicated that maximum and minimum degrees of bacterial density were observed in operation rooms and in the intensive care unit [ICU] of Shafa hospital. Furthermore, comparison showed that the operating room at Afzalipour hospital had the lowest level of fungal contamination, while ICU at Bahonar hospital had the highest level of fungal contamination. The emitted fungi of Aspergillus and Penicillium along with the bacteria, staphylococci and Acinetobacter had greater frequencies. The means of bacterial density and fungal density were not equal across the studied hospitals and significant statistical, difference was observed between means of bacterial and fungal density [P
Conclusion: amounts of bacterial and fungal density were greater than those proposed in the American Industrial Health State Conference in 73.3% of the wards in the educational hospitals of Kerman city sampled in this study. Therefore it is suggested that implementation of some, necessary measures for continuous monitoring, promotion of hygienic disinfection standards, and ventilation systems are taken more seriously by stipulating regulations to control this important issue in the country's hospitals
RESUMO
Background and Aim: In the present study the influence of the different sulfate concentration on the anaerobic lagoon stabilization was investigated
Materials and Methods: The present study is an experimental research carried out on anaerobic stabilization pond pilot for 7 months in Birjand wastewater treatment plant. After making sure of a steady state sulfate with different concentrations of 200, 300 and 400 mg/L were injected into the pilot. Then parameters including pH, organic nitrogen, ammonia nitrogen, BOD5, COD and nitrate were measured. All of the experiments were carried out according to the methods presented in the book "Standard Method" for the examination of water and wastewater [2005]
Results: It was found that by increasing sulfate concentration from 200 to 300 mg/L all of parameters except BOD5 [10% reduction] had no significant changes, but by increasing the sulfate concentration from 200 to 400 mg/L the removal efficiency of the parameters such as BOD5, COD, Organic nitrogen, total kjeldahl nitrogen, nitrate and sulfate reduced to 11, 8, 12, 26, 6 and 10 percent, respectively. PH in the first stage was alkaline and then changed to acidic
Conclusion: Anaerobic stabilization ponds have different capacities for removal of organic compounds at different sulfate concentrations; so that; in sulfate concentration of 200 mg/L, the proper operation was seen and in concentration of 300 mg/L, sulfate-reducing bacteria get dominant and therefore odor is produced. Alternatively, by increasing the concentration of sulphate to 400 mg/L, ammonia nitrogen increased 2.5 times [150%] in the effluent
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Background: Entry of untreated wastewater of wool scouring factories has been associated with many environmental hazards because of high rate of pollution. Presently effective treatment methods and reducing the costs of operation and maintenance from treatment units have always been under the attention of this industry owners. The aim of this survey is to present a suitable method for the treatment of wool scouring
Methods: In this study, chemical coagulant is used for wastewater treatment [aluminum sulfate, ferric chloride, poly aluminum chloride and lime]. And then these materials with "ozone" as a strong oxidative in reduction of the amount of Chemical Oxygen Demand [COD] in wastewater effluent has been surveyed
Results: The results of this work showed that only ferric chloride and aluminum sulfate among the above chemical coagulant had a high efficiency in the turbidity removal. Productivity of turbidity removal using ferric chloride with the pH of 4 to 5 was 99%, and turbidity was reduced from 166 Nephelometric Turbidity Units [NTU] to 1.5 NTU, and productivity of turbidity removal using aluminum sulfate within the pH 4.5 to 5 was 99.33% that reduced turbidity from 166 to 1.1 NTU. Results of ozonation with 5 g/hour and the oxygen flow of 2.5 litter per min with the pH assess of 15, 30, 45, 60, 90, 120, and 150 min to wastewater from chemical treatment with ferric chloride showed that the rate of COD was reduced from 24700 mg/L to 2940 mg/L. In ozonation to wastewater of chemical treatment with aluminum sulfate within the above rang of time, the rate of COD was reduced from 22500 mg/l to 4800 mg/l
Conclusion: We can be hopeful that in near future, getting the cheap technology of ozone production in industrial scale, one can use this technology for the propose of removal of pollutants having removal preferable by help of advanced treatment approaches
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Background: This study quantified the effect of four popular culture media in a biodiesel production study on the qualitative and quantitative lipid content, dry biomass, and lipid productivity of Nannochloropsis oculata
Methods: Culture of microalgae was done separately in Walne, F/2, Sato, and TMRL media. In the logarithmic and stationary growth phases, biomass production and lipid accumulation of microalgae were measured and the constituents were identified by gas chromatography
Results: N. oculata exhibited the highest rate of cell growth and biomass productivity of 0.2616 day-1 and 2.652 gl-1 in the Walne medium. The highest level of biomass conversion into lipids in TMRL medium revealed a cell dry weight of 37.22%. Walne medium proved to have the most efficient lipid productivity which was 0.1057 gl[-1] day[-1]. The highest amount of triacylglycerol [TAG] was obtained in Sato medium in the stationary growth phase and was 75.25% of the fatty acids
Conclusion: The present study provides a practical benchmark, which allows the introduction of Walne as a suitable culture medium for N. oculata in biodiesel studies
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Background: Chlorophenols are classified as priority toxic pollutants. These acidic organic compounds present a serious potential hazard for human health and aquatic life. Chlorophenols accumulate in water, soil and air due to high stability, and impart an unpleasant taste and odor to drinking water and can exert negative effects on different biological processes. Among the different methods of removal, adsorption process by low price adsorbents, such as fly ash [FA] is common. Therefore, in this study, the effects of oxidation of FA as modified adsorbent were investigated when the adsorption of 2-chlorophenol [2-CP] was increased
Methods: This experimental study was conducted from March to September of 2013. FA obtained from Zarand power plant [located in Kerman province] was oxidized with potassium permanganate. Effective factors on the oxidation of FA, such as temperature, oxidation time and concentrations of oxidizers were optimized. Raw sewage of Zarand coal washing plant was tested under optimal conditions. All tests were carried out according to the standard methods book for the examination of water and wastewater
Results: Optimal condition for the preparation of oxidized FA was obtained at 70 degree C, 1 hour, and 1 mM of potassium permanganate concentration. The absorber obtained was able to remove 96.22% of 2-CP under optimized conditions [pH=3, 2 hours, adsorbent dose 0.8 g and room temperature]. The removal efficiency of the real wastewater under optimal conditions was 82.1%
Conclusion: Oxidized FA can be used for the removal of this pollutant from industry wastewater due to its high efficiency of removal in real wastewater, it is easy and inexpensive to prepare and could modify the sorbent
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Background: This study aimed at determining the appropriate method for dewatering and drying biomass and selecting a suitable organic solvent for lipid extraction
Methods: Nannochloropsis Oculata was cultured in Gillard F/2 medium and after reaching the end of the stationary growth phase, algal biomass was separated from aqueous by centrifuge and dried through three methods: Oven, Air-dried and Lyophilized. Soxhlet apparatus achieved lipid extraction of all samples: diethyl ether, n-hexane and n-pentane using three solvents. At each stage, the quantity and quality of the extracted lipids were determined by Gas Chromatography
Results: In all three drying methods, palmitic acid and palmitoleic acid, and most significantly fatty acid composition of microalgae were extracted. The fatty acid composition of palmitic acid extracted by Diethyl ether was significantly more than the other two solvents. Maximum production of triglyceride was observed in Lyophilized and air-dried microalgae where lipid extraction was performed with diethyl ether solvents and are 75.03% and 76.72% of fatty acid
Conclusion: The use of Lyophilized method for dewatering and drying of biomass and Diethyl ether as solvent for the extraction of lipids from biomass, studied in this paper, as compared to other methods, had higher yields and researches proved that the production of biodiesel from microalgae's lipid was more efficient