عنوان مقاله [English]
This study was conducted to determine the qualitative parameters of the wastewater from the Olefin Unit of Bandar-e-Imam Petrochemical Complex in an attempt to identify the problems and to develop solutions. All the oily wastes generated in the unit under study are directed to the CPI and DAF systems where they are deoiled, diverted into the Eastern Pond, and, finally, discharged into the sea after a primary treatment process. In this study, information was collected on the process and on the effluent contaminant spreading sources in order to determined the sampling spots. Sampling was performed over 6 months and the effluent quality parameters (pH, TDS, BOD, COD, Oil, SO4=, PO4≡, and NO−) were measured. Changes in the parameters were recorded on monthly, weekly, and daily bases. Combined samples were additionally used to ensure measurement accuracy. The results showed that the concentration levels of the parameters BOD, COD, oil, and phosphate ion in the effluent from the CPI system were beyond the national standards. Pollution load estimations for the relevant parameters also confirmed these results. Investigations revealed that COD and oil removal efficiencies in the CPI system were 17% and 10%, respectively, which cannot be desirable (paired sample t-test). Another problem observed was the effluent from the caustic wash tower. This effluent, which contains considerable quantities of caustic, polymer, yellow oil, and water, is discharged into the waste neutralization pond to leave the complex without further neutralization.