Research On The Control System Of Oil Field Sulphate-Reducing Bacteria Corrosion

Sulfate-Reducing Bacteria (SRB) may corrode metals seriously. In the oil field ,as a result of SRB being fungus massive existences, not only corrodes the equipment, but also reduces the processing efficiency of the water-treating equipment and so on, therefore the controlling SRB is extremely essential. So the study on preventing metal from SRB corrosion is becoming more and more important.In this paper, Sulfate-Reducing Bacteria (SRB), which gains from the spot sewage water in the oil field is purified with solid mediums, conserved at low temperature and counted in Most Possible Number method. The bacterium is identified to belong to G- in both simple staining method and Gram's staining method.In the research SRB corrosion experiment, obtains SRB logarithm growth rule, 1-2 days logarithms slow-growing are the incubation periods, 3-6 days amounts of quantity rapid increase for its vegetal period, after the 6th day achieved the logarithm peak value the amount starts to reduce for its decline phase; Simultaneously obtains that the Q235 steel in SRB culture medium corrosion rate is quicker than in the asepsis culture medium corrosion rate, which proves that SRB has the function which the promotion corrodes, also the corrosion rate increases along with SRB density enlarges, reduces along with SRB density reduces; After the experiment the culture medium pH value from 7.2 to 6.1.In the research oil field spot sewage situation, discovered by when the sewage containing SRB puts drugs in the medium, SRB amounts also grow the same as the logarithm growth rule, difference is that achieves the peak value on the 7th day. After the experiment the culture medium pH from 7.8 to 7.3; After the corrosion rate in antiseptic sewage is lower than in the sewage with SRB.In order to prevent and control SRB corrosion, in using the cathodic protection and in the painted fluorine carbon coating situation, the test sample corrosion rate is lower than the painted fluorine carbon coating by far and not painted the fluorine carbon coating, the test sample is at the protection condition basically, simultaneously finds that the pH nearby the negative pole is alkaline which is not fit for the growth of SRB ,the bacterium amounts reduce. Thus the cathodic protection and the painted coating has the function which to protect the metal corrosion, simultaneously SRB amounts reduce to certain scope, which is a new way to solve the oil field physics sterilization .