19-06-2010, 07:26 PM
Microbial enhanced oil recovery techniques
Microbial Enhanced Oil Recovery (MEOR) is a potentially inexpensive method. The other methods of oil recovery processes are only able to retrieve from 15 to 50% of the available oil in the reservoir. The the average well life can be extended by the utilization of this technology . This can also spare the increasing excessive lifting costs.This is also a an environmentally compatible method for the tertiary oil recovery. more effective microbial bacteria can be developed by the genetic engineering and they may subsist on inexpensive and abundant nutrients.
TERTIARY RECOVERY:
Primary recovery typically recovers 10 to 35% of a reservoir's oil-in-place.The Secondary recovery,increase the recovery by 20% or more. The Enhanced oil recovery (EOR), also called tertiary oil recovery, enables oil producers to extract as much as 30 to 60% . chemical flooding, miscible displacement and MEOR are the main tertiary oil recovery techniques used. microorganisms may contribute to EOR in six ways.
-microorganisms grow in reservoir rock pore throats and produce chemicals to recover trapped oil.
-biosurfactants and biopolymers are produced by them on the surface.
-high-permeability channels in reservoir rock can be selectively plugged by the microbes so that there is increased efficiency.
-biocracking: here the microbes metabolize carbon atoms from the interior of an alkane chain.
-biocompetitive exclusion: here an undesirable population is replaced by a desired one such as the as denitrifying bacteria.
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http://findarticlesp/articles/mi_m3159/is_10_227/ai_n16850405/