Kwong Lee Oilfield Corrosion Mechanism And Anti-corrosion Measures Discussed

Aim at the corrosion condition of the guangli oil-field, by the method of the etched potential, voltaic potential scanning and circulate volt-ampere polarization, we study the corrosion trend, the corrosion property and the point corrosion trend of the output water from the guangli station and the liquid between the hollow in the different depth well. We found out the strong corrosiveness reason of the water, the free carbon dioxide, the pH is worth 6.0 or so, that belongs to the weak acidity corrosiveness medium, and the dissolved oxygen, the high degree of mineralization, the incrustation etc. The recycled pumped water from the distance travelled by a stream of water to inject well will be deteriorated and the corrosiveness is heightened belong the flowing technology, because recycled pumped water environment and the system have the corrosiveness. In all, the main reason of the guangli station corrosiveness is the free carbon dioxide, the reproducing bacterium, the mineralization, the dissolved oxygen and the cell corrosiveness of the concentration gap below the incrustation etc.We study the corrosion mechanism of the oil tube and the casing in the guangli station by the SEM. The corrosion mechanism of the first or second casing which is near the surface, is oxygen corrosion by the chlorine ion. The corrosion mechanism in the 100 meter casing, is oxygen corrosion by the chlorine ion and the carbon dioxide corrosion. The corrosion mechanism from 100 to 1000 meter, is carbon dioxide corrosion and a little SRB corrosion. The corrosion mechanism from 1000 to 2000 meter casing, is the main carbon dioxide corrosion. The corrosion mechanism below 2000 casing is complex, that is the common result of the chlorine ion, carbon dioxide and SRB, and the affect has the order. But in the all, the main corrosion element is the carbon dioxide. In all, in the corrosion element of the guangli oil-field, the carbon dioxide, SRB and the mineralization have been action, but the carbon dioxide is the main corrosion element.We probed into the shelter measure about the corrosion, the applied the shelter measure is to use the compound metal tube that can endure corrosion, or to plus the chemical reagent, use the pictured tube and the electrochemistry protection. By the spot application of the plusing the chemical reagent and making the stagnant water flow, the protect corrosion effect is obvious, and the water modified technology is applied in the guangli station...