Microorganisms, surfactants produced

One recent attempt to decrease the costs associated with surfactant flooding has been to inject surfactant-producing bacteria into oil reservoirs. This technique involves the injection of selected microorganisms into the reservoir and the subsequent stimulation and transportation of their growth products in order to recover more of the oil-in-place [34]. Some of the mechanisms proposed by which these microbes can stimulate oil production include reservoir repressurization, modification of reservoir rock, degradation and alteration of oil, decrease of viscosity, and increase in emulsification [35]. 

Biosurfactants can also be employed for in-situ oil recovery either by innoculating the petroleum reservoir or by producing the compound on the surface and injecting it into the well. If the surfactant is to be produced in place, it is necessary to select the microorganisms which produce good yields of biosurfactants. Improvements in yields and fermentations which use cheaper substrates than carbohydrates are needed. 

Lang S. 2003. Surfactants produced by microorganisms. In Hobnbetg, K. (editor). Novel Surfactants Preparation, Applications, and Biodegradability, 2nd Edn. New York Marcel Dekker, Inc. pp. 279-315. 

Table 10 Major Types of Bio surfactants Produced by Microorganisms... 

Surfactants can be either found or synthesized to contain both hydrophobic and hydrophilic regions and can be cationic, anionic, or neutral. Cationic surfactants can be chosen to extract metals from soil. Of particular interest are those anionic surfactants that are naturally produced by plants and microorganisms because they can easily be broken down in soil once extraction has been accomplished. However, the use of surfactants for extracting metals has found limited use [27],... 

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