Heavy metals (Nickel and Zinc) pollution of industrial waste of storage tanks and petroleum products distribution of Shazand oil refinery

Oil contamination is an inevitable consequence of rapid population growth. The non-stop usage of oil resources on a large-scale is increasing and it is a major cause of pollution. In the present study, nickel and zinc pollution as heavy metals found in the waste from petroleum product storage tanks was investigated. Sampling was conducted randomly and from six different types of oil tanks based on the type of products manufactured, and repeated three times for each tank. Since the samples were aggregated into three different phases (organic, watery, watery and organic phases), a special method of analysis was used for each phase. The results showed that the average concentrations of nickel and zinc in the waste of the storage tanks were 141.5 mg/l and 087.7 mg/l, respectively. The comparison of waste concentrations with the standards of the environmental protection agencies of America and Iran showed that, in 25% of samples, the nickel concentration is higher than the standards while 75% of samples have the equal or smaller nickel concentration. Also, the Zinc concentration was higher than the standards in 20% of samples. Finally, with regard to the importance of the ecological status of the Shazand area, control of heavy metal pollution and monitoring of waste oil reserves in the region is emphasized, which requires accurate and timely management in order to prevent an increase in these pollutants.