Crude Oil Industry

In the recent scenario, the oil industry is experiencing undesirable changes, which are mainly the cause of violation of the prices. As the availability of crude oil is increasing, environmental concerns are increasing and the supply is not able to cope up with the demand. This situation is challenging for refineries operation all over the world. Transportation fuel constitutes the largest part of the oil market. Refining is one of the most complex and dynamic manufacturing process which requires continuous updating and renovation; it has developed from simple distillation process to highly sophisticated mixture of processes that mainly separates the crude into simplified fractions.

Crude oils are the mixture of paraffins, naphthenes (or

It uses less energy for heating (since bioprocesses operate at room temperature or at the most 80_C), reduces green house gases such as CO2, as well as less production of NOx, SOx, etc. takes place. Along with these there are some more advantages which include the following:

• Direct conversion of toxic compounds (sulfur and nitrogen compounds, hydrogen sulfide, polyaromatics, etc.) to an easily removable or desirable product.
• No requirement for secondary recoveries, minimizing waste management.
• Low energy requirements, since the processes operate at ambient temperatures.
• Inexpensive cost of chemicals (mineral salts, nutrients).
• Minimal problems of catalyst corrosion (moderate pH).
• Minimal disposal problems (negligible hazardous wastes).
• High-protein biomass as by-product (potential revenue

It ranges from 1000 – 30000 ppm in crude oil (Monticello, 2000). Moreover, high-sulphur diesel could duplicate NOx emissions and causes environmental contamination (USEPA,1998). Hydrodesulfurization (HDS) removes sulphur and nitrogen, into hydrogen sulfide and ammonia, satisfying the current regulation of 500 ppm sulphur in diesel. As deeper HDS (below 200 ppm) requires higher temperature (265 - 425°C), pressure (75 - 100 kg/cm2) and larger quantities of hydrogen (290 - 1260 scf/bbl) which in turn results in high investment as well as cost (Speight, 1998; Gonzalez, 1996; EIA). Biotechnology based techniques are attractive and innovative alternatives as they can selectively desulfurize the alkylated DBTs (recalcitrant to hydrodesulphurization) under less severe reaction conditions in an energy intensive manner. Biodesulfurization involves the use of microbial or enzymatic system that selectively oxidizes the sulphur atoms or removes sulfur without attacking the C-C backbone and avoiding the lost of oil value (Kilbane, 2003; Furuya et al., 2001). It has also been investigated that BDS processes also involve the use of isolated enzymes because of its greater technological utility in organic solvents. An enzymatic desulphurization approach as compared to the utilization of complete cells would have at least three advantages i.e. activity at low water