Fan Yuxing, Chen Cuiying, Zhang Yuxuan, Liu Haixian, Liu Hongwei, Liu Hongfang
School of Chemical Engineering and Technology, Sun Yat-sen University, Zhu Hai 519082, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Zhu Hai 519082, PR China.
School of Chemical Engineering and Technology, Sun Yat-sen University, Zhu Hai 519082, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-sen University, Zhu Hai 519082, PR China.
Bioelectrochemistry. 2021 Oct;141:107880. doi: 10.1016/j.bioelechem.2021.107880. Epub 2021 Jun 29.
Microbiologically influenced corrosion (MIC) is one of the reasons leading to the service failure of pipelines buried in the soil. The effects of sulfate-reducing bacteria (SRB) on steel corrosion without organic carbon are not clear. In this work, SRB cells were enriched in the simulated soil solution, aiming to study SRB corrosion behavior without organic carbon source using weight loss, electrochemical measurements, and surface analysis. Effects of DO on SRB corrosion were also studied. Results indicate that SRB can survive after 14 days of incubation without organic carbon source, but approximately 90% SRB have died. SRB without organic carbon source could inhibit the uniform corrosion but enhance the pitting corrosion compared with the control specimen. The corrosion rate of the control calculated from weight loss is highest with a value of (0.081 ± 0.013) mm/y. The highest localized corrosion rate of (0.306 ± 0.006) mm/y is obtained with an initial SRB count of 10 cells/mL. The presence of DO influences the steel corrosion process. Oxygen corrosion dominates for the specimens in the absence and presence of SRB with an initial count of 10 cells/mL, while SRB MIC is primary for the specimens with high SRB counts.
微生物影响下的腐蚀(MIC)是导致埋地管道服役失效的原因之一。硫酸盐还原菌(SRB)在无有机碳情况下对钢腐蚀的影响尚不清楚。在本研究中,在模拟土壤溶液中富集SRB细胞,旨在通过失重法、电化学测量和表面分析研究无有机碳源时SRB的腐蚀行为。同时也研究了溶解氧(DO)对SRB腐蚀的影响。结果表明,在无有机碳源的情况下培养14天后SRB仍可存活,但约90%的SRB已死亡。与对照试样相比,无有机碳源的SRB可抑制均匀腐蚀,但会加剧点蚀。由失重法计算得出的对照试样的腐蚀速率最高,为(0.081±0.013)mm/y。当初始SRB数量为10个细胞/mL时,局部腐蚀速率最高,为(0.306±0.006)mm/y。溶解氧的存在会影响钢的腐蚀过程。对于初始数量为10个细胞/mL且有无SRB的试样,氧腐蚀占主导,而对于SRB数量较高的试样,SRB引起的微生物腐蚀是主要的。