Treatment of contaminated soil to petroleum hydrocarbons with Vetiver phytoremediation

Industrialization can be one of the main causes of environmental pollution increasing, especially petroleum hydrocarbons in the water, air, and soil. Polluted soils in the evaporation ponds are one of the primary sources of pollution in the oil refineries. Phytoremediation is the use of plants to remove contaminants from contaminated soils, to accumulate them in the roots and to remove them from the stems and leaves, or to decompose these compounds within the plant. Choosing the right plant, especially in soils with low or moderate pollution, plays an important role in the process of phytoremediation. Vetiver is a suitable plant for phytoremediation. In this project, first, soil samples were collected and the survival and resistance of vetiver were investigated. After that, executive works started in the Dalan area, including planting plants in the area, installing a reservoir, installing a drip irrigation system, sampling contaminated and non-contaminated soils in the area, and sampling the soil adjacent to the plant roots and measuring the amount of Petroleum hydrocarbons. The vetiver plant can grow and survive in oil-polluted soils. After a year of phytoremediation effect, the Vetiver plant reduced the amount of total petroleum hydrocarbons and aromatic hydrocarbons by about six times and nine times, respectively. Further phytoremediation treatment with vetiver root (soil rhizosphere near the root) could further reduce the amount of total petroleum hydrocarbons and aromatic hydrocarbons.