Small-grained sulfur with additives is introduced to the soil polluted by oil. Owing to humidification and aeration, a positive environment for generation and growth of sulfur bacteria colonies is created. Microorganisms and thiobacteria (thiobacillus, thiooxidanus and others) contained in sulfur start growing and biologically decompound oil wastes using them as carbon nutrition.

Biological decomposition releases hydrogen sulfide, organic acid, alcohols and aldehydes characterized by surface activity and contributing to intensive cleaning of oil from soil particles owing to the reduction of the strain between soil and oil. Porous surface of the adsorbent accumulates water and air in the pores, which improves soil aeration and creates favorable conditions for decompounding activity of microorganisms and thiobacteria.

We conducted tests on optimization of small-grained sulfur with additives. In the result of tests conducted during two years both in the laboratory and on the testing ground we revealed the following:

1. At positive temperature sulfur grains dissolve in the wet soil during not more than a day.

2. At the increased temperatures the process is more intensive. More hydrogen sulfide is released. After completion of biological decomposition, release of hydrogen sulfide stops.

3. Laboratory studies of samples before and after the processing showed the reduction of content of oil and sulfur to the certain sanitary regulations and norms. Test samples of standard soil and processed soil were used to plant barley. Growth of plants was near the same at the same attendance.

4. АIt is also possible to process oil waste containing great amount of hydrocarbons, contaminations and water by mixing with natural soil in the soil mixer in order to average the concentration of oil waste to 25-30%.

Figure 1. A plot of oily soil before processing on August 14, 2008.

Figure 2. The same plot after processing on October 7, 2008.