硫酸盐还原菌的腐蚀机理

Corrosion Mechanism of Sulfate Reducing Bacteria

采用硫酸盐还原菌 ( SRB)培养技术 ,研究了 SRB的生长特性 ,结果表明 :在 SRB的整个生长过程中 ,培养液中 SO2 -4 浓度逐渐减小 ;但当 SRB处于繁殖期时 ,H2 S释放量逐渐增大 ;处于衰亡期时 ,H2 S释放量逐渐减小。同时 ,对三种油田管材进行浸泡试验 ,采用扫描电镜对试样腐蚀产物形貌及组成进行分析 ,发现腐蚀产物主要为 Fe S和 Fe1-x S。着重研究了 SRB的腐蚀机理 ,结果表明 :SRB的代谢产物 ,特别是 H2 S,是加快腐蚀的主要原因 ,它们对腐蚀反应即有阴极去极化作用 ,又有阳极去极化作用。

With cultural technology of sulfate-reducing bacteria(SRB), growing character of SRB is researched. The result shows that SO2-4 consistency will decrease as SRB growing. But with SRB multiplying, H2S consistency will increase; with SRB declining and falling, it will decrease. In the meantime, with three petroleum tubular materials soaked, the form and composition of the corrosion products are analysed with scanning electron microscopy(SEM), and it is found the corrosion products are FeS and Fe1-xS. The corrosion mechanism is amphatically researched and its result shows that the main cause of accelerating corrosion is the products of SRB, because of metabolism, especially, H2S. They have both anode depolarization reaction and cathode depolarization reaction to corrosion reaction.