Investigation and comparison of concentration and Accumulation of Heavy Metals (Hg, Pb, Ni, V) in Raw and Treated Wastewater from Amir Kabir Petrochemical Company in Bandar Imam Khomeini and Sediments of Shadegan Wetland

Komasi, Mohammad; Monavari, SeyedMasoud; Zamani Hargalani, Fariba; Baikpour, Shahram

Volume 17, Issue 3 (Autumn 2025) 3 2025, 17(3): 81-93 | Back to browse issues page

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Komasi M, Monavari S, Zamani Hargalani F, Baikpour S. Investigation and comparison of concentration and Accumulation of Heavy Metals (Hg, Pb, Ni, V) in Raw and Treated Wastewater from Amir Kabir Petrochemical Company in Bandar Imam Khomeini and Sediments of Shadegan Wetland. 3 2025; 17 (3) :81-93
URL: http://jmb.ahvaz.iau.ir/article-1-1015-en.html

Investigation and comparison of concentration and Accumulation of Heavy Metals (Hg, Pb, Ni, V) in Raw and Treated Wastewater from Amir Kabir Petrochemical Company in Bandar Imam Khomeini and Sediments of Shadegan Wetland

Mohammad Komasi

, SeyedMasoud Monavari

, Fariba Zamani Hargalani

, Shahram Baikpour

Department of Environmental Sciences, Faculty of Natural Resources and Environment, Islamic Azad University, Science and Research Branch, Tehran, Iran.

Abstract: (555 Views)

Industrial wastewater from petrochemical industries, due to the presence of various organic and inorganic compounds, poses a significant threat to the health of aquatic ecosystems. This study aimed to measure the concentration and investigate the distribution pattern of heavy metals (mercury, lead, nickel, and vanadium) in the wastewater units of the Amir Kabir petrochemical complex, as well as to assess their accumulation in the sediments of the international Shadegan wetland. In this research, 15 raw wastewater samples, 15 treated effluent samples, and 15 surface sediment samples were collected from 4 strategic stations. Metal concentrations were measured following sample preparation and acid digestion according to standard methods using an ICP-OES 730-ES model. The results revealed that the metal concentrations in the incoming wastewater exhibited a wide range of variations due to the diversity of processes in the operational units, with mercury ranging from 0.02 to 6.09, lead from 0.02 to 2.23, nickel from 0.76 to 26.88, and vanadium from 6.54 to 20.13 micrograms per liter. The highest pollution load was observed in the olefin unit, while the lowest was found in the butene-1 unit (P<0.05). The treatment process led to a significant reduction in the concentrations of all metals in the effluent (P<0.05). However, metal concentrations in the wetland sediments (mercury: 1.56–6.17, lead: 0.92–5.06, nickel: 19.55–59.42, and vanadium: 30.65–68.05 micrograms per gram) were significantly higher than in the liquid phase. The pollutant accumulation pattern identified was sediment > incoming wastewater > treated effluent, indicating the role of sediments as the final sink for persistent pollutants. A significant positive correlation between metals in the sediment and organic matter, as well as a strong relationship between nickel and vanadium, confirms their common oil and catalytic origin. Comparison with EPA and NOAA standards showed that metal concentrations in the sediments of stations near the wastewater discharge site exceeded the permissible thresholds, requiring urgent environmental management.

Keywords: Heavy metals, Industrial wastewater, Activated sludge, Sediments, Shadegan wetland.

Full-Text [PDF 994 kb] (268 Downloads)

Type of Study: Research | Subject: Pollution
Received: 2024/11/19 | Accepted: 2025/11/24 | Published: 2025/11/24