Pollution with petroleum wastes is a serious environmental problem that must be treated considerably. Artificially polluted soil with oily contaminants mixtures was treated biologically using aerated bioreactor. The used oily mixtures used in this study are petroleum sludge, lubricating oil and crude oil. Crude oil and petroleum sludge were obtained from oil refinery of Al-Romayla at Al-Basrah governorate, tests were examined at the Ministry of Science and Technology. These wastes were mixed separately with soil in a ratio 7(pollutant):100 (soil) and treated by using the bioreactor. The degradation ability of microorganisms existed in the soil had been examined in low weather temperature with the aid of enzymatic reagent. The efficiency of removing the organic hydrocarbons after five weeks of treatment was 68.2 %, 74.4 % and 77.7 % for the petroleum sludge, lubricating and crude oil, respectively. The obtained results show the ability of the enzymatic reagent in the activation of micoorganisms to degrade heavy hydrocarbons substances even in cold weather.

Partial degradation of organic materials presented in sewage water had been conducted in the current research in a simulated sewer system. The process had been improved by aeration and seeding with activated sludge to reveal the effect of increasing the amount of biomass in the system. Three ambient temperatures were conducted as 10, 20, and 30 O C to display the influence of temperature on the degradation process. The results revealed that adding activated sludge to the system in a ratio of 50/50 (v/v) had a significant influence on the degradation as more microorganisms required more organic nutrients. In the other hand, increasing the operating temperature indicated positive influence in terms of soluble chemical oxygen demand (SCOD) removal as temperature motivated the living biomass towards severe degradation.

Introduction: Pollution with oil products considered one of the most environmental problems that need to be treated significantly.Artificial polluted mixtures of pollutants and soil had been bio-treated via aerated bioreactor. Methods: Mixtures of used lubricating oil, crude oil and petroleum sludge had been mixed individually with soil in pre-determined ratio and treated via the bioreactor. The living microorganisms existed in soil were reinforced with enzymatic accelerating reagent to examine their activity in relatively cold ambient temperature. Results and Conclusion: Percentage of removal for the total organic hydrocarbons was recorded to be 74.4 %, 77.7 % and 68.2 % at the end of the fifth week of treatment of the three studied mixtures, respectively. This gives a significant indication of the ability of the used reagent combined with existing microorganisms to dissolute heavy hydrocarbon substances contaminates the soil in extreme ambient conditions.