Qom University of Medical Sciences Journal

Background and Objectives: 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.

Methods: 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.

Results: 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 O₃ 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.

Conclusion: 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.