M Ghanbari, K Nadafi, M Mosaferi, M Yunesian, H Aslani,
Volume 4, Issue 3 (1 2011)
Abstract
Background and Objectives: Over the last three decades environmental pollutions became a more noticeable problem in all around of the world. In many countries, noise pollution as a basic problem has a great importance.Development of the city, increasing of industrial centers, increasing vehicles, other annoying noise resources and also little information about the noise pollution of Tabriz city, has led to the doing of this research.
Materials and Methods: Sampling and measuring of noise pressure levels was done 180 times According to the EPA standards, measuring was done simultaneously in two stations(commercial-residential areas), three times a day (morning 7:30 -9:30 am, midday 12:30-14:30 pm and night 19:00-21:00 pm) and 30 days in month.
Results: Sound pressure level in both stations was higher than the standards and the highest average level with 71.4 db was recorded in Raste-koche station at midday. Also lowest calculated average value with 68.5 db was measured in Golbad station at the morning time that is 8.5 db higher than the standards.
Conclusion: Average measured sound pressure level in two stations was higher than the standards. The results show that Tabriz has a noise pollution in commercial and residential - commercial areas. It is suggested that other noise pollution resources identified and the proper management actions for its reduction be done.
Mostafa Leili, Gholamreza Moussavi, Kazem Nadafi, Rasoul Khosravi,
Volume 6, Issue 2 (9-2013)
Abstract
Background and Objectives: Furfural with a chemical formula of C5H4O2 is a toxic and hazardous substance for human and environment. Furfural and its derivatives such as furfuryl alcohol, alone or in combination with phenol, acetone or urea are used mainly in the production of resin. The second major application of furfural is in the production of solvents such furan and tetrafuran frequently used as a selective solvent in the production, treatment, and refining lubricants from petroleum products. A few studies have recently been done in terms of removal or recovery of furfural. Due to advantages of biological methods, the uses of theses environmentally friendly methods are being investigated in this study.
Materials and Methods: We used cyclic biological reactor (CBR) and Fusarium culmorum granules to biologically degrade different concentration of furfural and equivalent of COD under different operating conditions. The analysis was based on the measurement of furfural degradation efficiency during operational period using spectrophotometer and measuring influent and effluent COD variations using a closed reflux method.
Results: cyclic biological reactor was operated in various flow rate (Q) of furfural-containing wastewater for a different period. For all of the flow rate used, furfural degradation and COD removal efficiency was over 99 and 90 percent respectively. Fusarium culmorum granules were also exposed to different concentrations of furfural at different incubation temperatures showing high furfural removal capacity. Conclusion: Under different operating conditions of biological systems, high removal efficiency of furfural was observed, but CBR in comparison with Fusarium culmorum granules reached the optimum and desired removal efficiency in shorter time. Therefore, these systems can be developed and replaced with chemical methods to treat furfural containing wastewater.
