SRB Corrosion Component of SEW N80 Oil Casing in Oilfield Produced Fluid

The sulfate reducting bacteria(SRB) corrosion component of SEW N80 oil casing in Qingerlian produced water of Changqing oilfield was studied by culturing SRB bacteria. The results showed that the number of SRB in Qingerlian produced water of Changqing oilfield was 103 pieces /mL, the growth cycle was 6~7 d, the growth peak was on the third day, the length was about 2.5 μm and the SRB belonged to corynebacterium without flagellum in the end. The corrosion rate of SEW N80 oil casing in the produced water caused by SRB accounted for 4.99% of total corrosion rate. To a certain extent, the SRB corrosion component contributed to total corrosion rate, but the contribution value was small. In addition, the corrosion resistance of base metal was equivalent to that of weld seam, and the surface of the tested specimens showed pitting corrosion and the main corrosion products were iron oxides.