Influence of Soil Characteristics on Bioremediation of Hydrocarbons Contaminated Soil

The growth of industrialization and population ultimately results in the pollution of soil, water, air and other components of the environment. The soil is a medium for the growth of plants and microorganisms; as such soil is a major component of a bioremediation system. Hence, research on bioremediation should take into account the influence of physical and chemical characteristics of the contaminated soil. The bioremediation of hydrocarbon contaminated soil has not received much attention of researchers. Thus, a series of laboratory experiments were conducted on three different types of soil, with the aim of developing a new method of bioremediation, in addition to other controlling factors, taking into account the physical and chemical characteristics of soil for remediation of hydrocarbon contaminated soil, and to identify the most suitable soil type, which is potential for bioremediation using indigenous microorganisms

Influence of Moisture Content and Oxygen Concentration on Biodegradation of Petroleum Hydrocarbons

The biodegradability of petroleum hydrocarbons was evaluated using petroleum oily sludge from VRL logistics ltd situated at Kengeri, Bangalore (India). The soil rich in native microorganisms was collected from Bangalore University campus and the same is used to prepare simulated contaminated soil. The initial Total petroleum hydrocarbons (TPH) concentration in the simulated contaminated soil was 83,940 mg /kg of soil. Biodegradation was examined for three different conditions i.e. four bioreactors for studying variation of moisture, four bioreactors for studying variation of oxygen and one bioreactor as control Treatability studies on TPH contaminated soil was conducted for 12 weeks to evaluate TPH mass loss rates under the most favorable conditions, for which a set of nine bioreactors each with 15 kg of fresh soil, 3 kgs of oily sludge, 1.5 kgs of inoculated soil in the ratio of (10:2:1) were thoroughly mixed and maintained under laboratory conditions. The TPH, moisture content, pH, bacterial counts and oxygen were monitored regularly along with the nutrient concentration i.e.. C: N: P ratio maintained at 100:10:1 in all the bioreactors except the control reactor. From the study it is concluded that the optimal conditions for better degradation of TPH is found to be between 50% - 60% of moisture content with biodegradation rate of 0.0128 - 0.0174 day1 and TPH removal efficiency of 68.5 - 79.2% and oxygen concentration of 50 - 60 mg/kg/day, with biodegradation rate of 0.012