LARGE SCALE BIOREMEDIATION OF PETROLEUM CONTAMINATED SOIL

Large areas of soil are historically contaminated with petroleum hydrocarbons, mainly due to lack of environmental protection legislation and careless oil extraction in the past. In some cases, one of the potential remedial actions may be the bioremediation of the oil contaminated soil, due to low cost and low environmental impact. The focus of this research paper was to analyze the efficiency of the ex-situ bioremediation of oil contaminated soil at a large scale, in the open air. The investigations were performed by an ex-situ method in a bioremediation plant with a large capacity. Experiments were conducted both in open air (large scale, less controlled environment) and in the laboratory (small scale, controlled environment). Aeration of the contaminated soil was done using a windrow turner that also had a sprinkler system mounted on it for humidity control. Laboratory analysis was conducted at the beginning to check the availability of petroleum degrading indigenous organisms in soil. The hydrocarbons degrading speed was higher in the field trials under laboratory conditions, but only in the first phase. The experiments showed up that the overall remediation speed in a longer period of time tends to be equal in laboratory and in uncontrolled environment.