Native Bacterial Mixed Culture: A Proportionate Solution for Refinery and Petrochemical Wastewaters

Abstract

Background: Heat, chemical and organic pollution are three types of environmental pollution, caused by refinery and petrochemical industries. Problems caused by hear and chemical pollutants are currently resolved to some extent but organic pollution such as Poly Aromatic Hydrocarbons (PAHs) are still considered as important problems of industry and environment. Objectives: A laboratory study was carried out to investigate the effects of native bacterial mixed culture (BMC) isolated from mixtures of refinery and petrochemical wastewaters for treatment of wastewaters of refinery and petrochemical industries. Materials and Methods: All bacteria were isolated from two refineries and two petrochemical plants of Iran. Several bacterial strains from both kinds of wastewater were mixed and two final stock culture collections (BMC a and BMC b), showed the ability to improve the growth among strains. BMC a was added to the refinery wastewater (activated sludge influent sample) and BMC b was added to petrochemical wastewater (activated sludge influent sample). The effects of continuous and non-continuous aeration at high and low pressures, along with the effects of nutrient addition in the beginning of experiment versus sequential addition at specific time intervals, were studied. Results: Native BMC, when continuous high level aeration was used, decreased chemical oxygen demand (COD) in refinery and petrochemical wastewaters for about 81% and 63%, respectively. Gradual addition of nutrients increased COD removal of refinery and petrochemical wastewaters to 85% and 87%, respectively. Conclusions: Native BMCs from mixture of refineries and petrochemical wastewaters can be an effective method of wastewater treatment of both regional refinery and petrochemical plants. High pressure continuous aeration and gradual nutrient addition to the native BMCs can improve bioremediation of organic wastewater in different industries.

Recent Proportionate Treatment Methods for Crude Oil Contamination Evaluation of the Tehran Refinery Site Soil

“…Tehran Refinery is one of the largest refineries in Iran and Middle East, with a nominal capacity of 225,000 barrels per day and an n operational capacity of 240,000 barrels per day (8). Tehran Refinery products are liquid gas, ordinary gasoline, light and heavy naphtha, kerosene, gas oil, furnace oil, mineral oil, and sulfur (9) and its wastewater has a high chemical organic demand (COD), close to 900 mg/L (10). The recent increases in the activities of Tehran Refinery, despite the old transmission lines and tanks, have resulted in the crude oil leakage and consequently, possibility of soil and following underground water contamination with crude oil compounds.…”

Bioremediation of The Crude Oil Contamination of Soil by The Indigenous, Herbaceous Plant Salicorniaeuropea in Iran

“…The half-life of Phenanthrene is approximately 16-126 days in soil sediments (6). Organic contaminations, especially PAHs, are more than standard values in petrochemical and refinery wastewaters (7); these PAHs contaminations are spreading in the surrounding area of these industrial locations. Phytoremedition has several advantages as the removal method of choice in the mentioned areas.…”