[ process of coagulation, flocculation and advanced oxidation in effluent treatment of second refinery oil industries]

One of the industries dependent on oil compounds that play an important role in economy, preserve resources and oil reserves, as well as environmental protection is the secondary refinery Oil industries. The efficiency of Coagulation, flocculation and advanced oxidation process in the Effluent treatment industry was studied. This study is a descriptive- quasi-experimental that effluent pollution quality measured with COD. Physicochemical processes of coagulation, flocculation, by using conventional coagulants and oxidation with ozone for the removal to access environmental discharge effluent standards were studied. Coagulants such as aluminum sulfate, ferric chloride, sodium silicate, poly aluminum chloride were evaluated. Jartest was used to determine the efficiency of coagulation and flocculation. Samples were collected from Salafchegan industrial district in Qom. Examination methods were extracted from Standard methods for water and wastewater examination. Initial experiments showed that BOD, indicating biological treatment wastewater, in comparison with COD, indicating chemical oxygen demand of wastewater is very low. Thus, the application of biological processes of effluent treatment without using chemical processes, not performance and not economic. The experiment showed that the amount of COD in raw effluent was varied from 38000 to 78000mg/l. Using advanced oxidation with O[3] in pH=11.5 can reach 77.5% and in pH=9 in 57.2 and in pH=3.25 in 21.3 COD removal efficiency respectively. According to the results, advanced oxidation process prior to biological effluent treatment of the second refinery oil industries is effective in eliminating pollutants and toxic substances

[ physical, chemical and microbial quality of treated water in Qom's desalination plants]

Water is the basis of life and health. The health of food and water supply plays an important role in human health. One of the methods of water desalination is membrane filter reverse osmosis method. This method is used for desalination of drinking water supply in Qom. This is a descriptive, cross-sectional study designed to determine the quality of treated water in Qom desalination plant in year 2002. Inlet and outlet water samples of this plant were examined by the standard examination methods and the collected data were compared with national and international standards. Excel software was used for statistical analysis. The results showed that the residual chlorine concentration, total hardness and fluoride concentration were lower than the minimum standard limit set for drinking water. The pH was also lower than the minimum standard limit. Microbial contamination was detected in 6% of samples. The results show that the acidity of water was lower than standard in whole plant. This gives corrosive properties to the water and increases the dissolution of materials, which are in contact with this water. In order to eliminate the secondary contamination, the concentration of residual chlorine should be 1 mg/l. But, none of the measurements showed a concentration as high as this value. As fluoride is an important element for health and growth of bone and teeth, especially in growing children, fluoride should be added to the drinking water. As the relationship between hardness of water and cardiovascular diseases has been established, it can be concluded that this drinking water supply can increase the risk of cardiovascular diseases in long time. Dilution of this water is recommended to adjust various factors to the standard limits and keep the total dissolved solids low