Microbial degradation of oil

In the name of Allah who is the most beneficient and merciful

Microbial degration of oil is the possible infection of an oil system by micro organisms. these live
by consuming hydrocarbons in the base oil togather with nitrogen, sulphur and phosphorus from additives.
if water is present they will multiply rapidly in the warm, agitated conditions in the oil system. contamins is
humids climates or accidental entry of dirt and water during overhaul.

infection by microorganisms will form organic acids and more water while depleting the additives. This will cause
corrosions and wear of metal surfaces(particularly bearing metals) and will create sludge and slime that choke oil filters.
The oil may be prone to emulsification and saponification.

Test for microbial infection make use of a special gel which is either dipped in the oil or has oil poured over it and is then
incubated to develop a growth or culture. the appearance of this culture is then compared visually with a standard coloured
chart, to indicate the degree of contamination if any. If the oil doesnot wet the get, it may be necessary to mix the sample with a
small quantity of sterile water.

contamination doesnot commonly occur if cleanliness and care are exercised and water is eliminated from the sytem. Recommendations are that a
maximum of 0.2 % of water content must not be exceeded when using detergent oils.


WRITTEN BY S/C ZEESHAH AHMED
LECTURE BY: CHIEF ENGR. Tahir jamil
Phone no. 03344011232
EMAIL: ZEETEC4@YAHOO.COM
date: 03.nov.2009