Treatment of Natural Waters Subjected to Perennial Petroleum Hydrocarbon Pollution Using Green Microalgae

The method of water treatment of natural objects subjected to long-term oil pollution with the use of green microalgae Chlorella vulgaris Beijer is proposed. It is shown that introduction of Chlorella in concentration of 2.9×10 6 cl/mL leads to reduction of oil hydrocarbons concentration by 86.6–100 %, and increase of Chlorella concentration up to 6.3×10 6 cl/mL allows to reduce oil content by 94.5–100 % at initial concentration of 15.4–148 MAC. It was found that the introduction of Chlorella reduces the level of water toxicity by 1.1–35.9 times. It is concluded that the introduction of green microalgae Chlorella vulgaris Beijer provides purification of chronically polluted water with petroleum hydrocarbons to the values approaching to the normative ones (1.06–4.2 MAC) and also reduces the toxicity level to slightly toxic/non-toxic.