| MEOR agents |
Microbes |
Product |
Possible application |
| |
Bacillus sp. |
Cells and EPS (mainly
exopolysaccharides) |
Selective plugging of oil
depleted zones and
wettability angle alteration |
| Leuconostoc |
| Xanthomonas |
| Surfactants |
Acinetobacter |
Emulsan and alas an |
|
| |
Bacillus sp. |
Surfactin, rhamnolipid,
lichenysin |
Emulsification and deemulsification
through
reduction of interfacial
tension |
| Pseudomonas |
Rhamnolipid, glycolipids |
| Rhodococcus sp. |
Viscosin and trehaloselipids |
| |
Arthrobacter |
|
Injectivity profile and
viscosity modification,
selective plugging |
| Biopolymers |
Xanthomonas sp. |
Xanthan gum |
| |
Aureobasidium sp. |
Pullulan |
| Bacillus sp. |
Levan |
| Alcaligenes sp. |
Curdlan |
| Leuconostoc sp. |
Dextran |
| Sclerotium sp. |
Scleroglucan |
| solvents |
Clostridium,
Zymomonas and
Klebsiella |
Acetone, butanol, propan-
2-diol |
Rock dissolution for
increasing permeability, oil
viscosity reduction |
| Acids |
Clostridium |
Propionic and butyric acids |
Permeability increase,
emulsification |
| |
Enterobacter |
| Mixed acidogens |
| Gases |
Clostridium |
Methane and hydrogenc |
Increased pressure, oil
swelling, reduction of
interfacial section and
viscosity, increase
permeability |
| |
Enterobacter |
| Methanobacterium |