PROJECT TITLE :

Online Monitoring of Crude Oil Biodegradation at Elevated Pressures

ABSTRACT:

So as to check the biodegradation of crude oil spilled in the deep sea, incubations of deep-ocean-bed sediments and crude oil were administrated in a very high-pressure reactor, however monitoring the biodegradation of oil at high pressure is restricted by sampling as a result of the volatile crude oil parts are partly lost during depressurization. Moreover, the seawater-oil-sediments multiphase system can't be sampled representatively. The aerobic oil biodegradation can also be monitored indirectly by measuring the oxygen consumed and therefore the carbon dioxide produced. In this paper, the O2 and CO2 concentrations were monitored in an exceedingly reactor with clear windows using chemical-optical sensors. To compare the effect of pressure on the biodegradation of oil, two pressure regimes were compared: atmospheric pressure (1 bar) and 150 bar, resembling 150zero m depth of the Deepwater Horizon's well at the Gulf of Mexico. Solely within the experiments where deep-ocean sediments were added, the oxygen concentration decreased while the carbon dioxide and therefore the bacterial concentration increased. In experiments where no sediment was added, the values for the oxygen and carbon dioxide remained constant. This proved that deep-sea sediments contained microorganisms, that might degrade crude oil at each 1 and 150 bar. To our data, this is the first time where O2 and CO2 were monitored online throughout crude oil biodegradation at high pressure in the laboratory.