喷气燃料中硫酸盐还原菌对金属的腐蚀

硫酸盐还原茵（SRB）广泛存在于石油中，SRB的存在会对石油储藏、运输过程中的管道和油库产生腐蚀。由于无法完全除去喷气燃料中的SRB，所以导致油库、管道和飞机油箱发生腐蚀，更有甚者，腐蚀产物会堵塞飞机发动机，带来灾难性的后果。通过改变喷气燃料中SRB自身浓度、所处环境的温度等条件，分析浸泡在喷气燃料中金属挂片的外观、质量和金相以及喷气燃料溶液pH值、硫含量等数据，来研究不同条件下喷气燃料中SRB对金属挂片的腐蚀情况。通过研究发现，当SRB浓度不超过10^6CFU／mL喷气燃料时，几乎不发生腐蚀，反之，腐蚀非常明显。SRB浓度越大，腐蚀越严重、通过改变温度环境发现，SRB最适宜生长温度为25℃，在此条件下腐蚀最为严重。浸泡在含有SRB的喷气燃料中的腐蚀挂片，其腐蚀程度随时间不断加深，尤其以第一周腐蚀最为明显。

Metal Corrosion by SRB in Jet Fuel under Different Conditions

The sulfate-reducing bacteria （SRB） widely exist in oil. The presence of SRB will corrode the oil pipelines and oil depots during storage and transpotlation of the oil. The jet fuel which is a petroleum product will corrode the oil tanks, pipelines and aircraft oil tank severely and the corrosion products can even plug aircraft engines and lead to catastrophic consequences because SRB can not be completely removed. By changing the SRB concentration in jet fuel and service temperature and applying the data of appearance, quality and metallography of metal coupon in jet fuel as well as pH value and sulfur content of jet fuel, the corrosion of SRB in jet fuel on metal coupon at different conditions is analyzed. The study finds that almost no corrosion occurs when the SRB concentration is lower than 106 cfu/ml. When the SRB concentration exceeds 106 cfu/ml, corrosion of metal coupon is very apparent. The corrosion becomes increasingly serious with rising SRB concentration. It is also found by changing the service temperature that SRB＇ s optimum growth temperature is 25 ℃, and thus the corrosion is most serious at this condition. The corrosion of coupons soaked in SRB-containing jet fuel is becoming increasingly deteriorated with time, especially in the first week.