复合菌种对海洋工程材料微生物腐蚀的影响研究

发布时间：2018-04-16 14:40

本文选题：微生物腐蚀 + 海洋工程材料　；参考：《浙江海洋大学》2016年硕士论文

【摘要】：随着陆地资源的日益紧张,人类逐渐把目光转向蕴含丰富资源的海洋,船舶、海洋平台、海底导油管道等海洋工程设施的数量不断增加。在海洋环境中,生物与微生物对海洋工程设施的附着,不可避免的使其寿命减短,造成严重的经济损耗,甚至在安全运行方面留下巨大的隐患。海洋细菌是海洋微生物研究中的重要分支,是海洋生态系统中重要环节,因此建立复合菌种对海洋工程材料腐蚀防护的基础理论,为我国海洋工程设施的设计、建造、选材提供理论保障,对提高我国海洋工程设计能力和建造水平都具有非常重要的现实意义。本论文主要采用电化学实验和腐蚀形貌观察等方法,在实验室条件下对海洋工程设施中常用黄铜和低碳钢两种材料,分别在硫酸盐还原菌、铜绿假单胞菌、噬油菌及其复合菌种等五种不同环境介质条件下的腐蚀行为进行了研究。实验结果表明,黄铜在单一硫酸盐还原菌菌种条件下,由于阴极去极化作用而加速腐蚀,且随着试样浸泡时间的增长,腐蚀电位负移,腐蚀电流密度正移,表明腐蚀加剧;在铜绿假单胞菌环境中,由于微生物膜的形成前期对于黄铜起到了一定的缓蚀作用,但随浸泡时间的延长,铜绿假单胞菌对黄铜缓蚀效果减弱甚至促进了腐蚀的进程;Q235低碳钢在硫酸盐还原菌单菌种溶液中由于阴极去极化作用促进了Q235钢的腐蚀,试样表面出现了大范围的局部腐蚀;在噬油菌中低碳钢腐蚀初期由于氧浓度差腐蚀速度加快,后期腐蚀反应减慢,试样表面腐蚀相对较轻;黄铜在硫酸盐还原菌和铜绿假单胞菌的复合菌种溶液中,黄铜腐蚀电流密度介于单一铜绿假单胞菌和硫酸盐还原菌种的腐蚀电流密度之间;Q235低碳钢在硫酸盐还原菌和铜绿假单胞菌的复合菌种溶液中,腐蚀电流密度均小于两种单一菌种作用时的腐蚀状态,两个试验结果均说明铜绿假单胞菌抑制了硫酸盐还原菌的生长;Q235低碳钢在噬油菌和硫酸盐还原菌复合菌种中的腐蚀状态与其在噬油菌单一菌种中的腐蚀前期状态相类似,也说明是噬油菌抑制了硫酸盐还原菌的生长。
[Abstract]:With the increasing shortage of land resources, the number of marine engineering facilities, such as ocean, ships, offshore platforms, submarine oil pipelines and so on, is gradually increasing.In the marine environment, the attachment of organisms and microbes to marine engineering facilities will inevitably shorten their life, cause serious economic losses, and even leave a huge hidden danger in safe operation.Marine bacteria is an important branch of marine microorganism research and an important link in marine ecosystem. Therefore, the basic theory of composite bacteria for corrosion protection of marine engineering materials is established to design and build marine engineering facilities in China.It is of great practical significance to improve the design ability and construction level of marine engineering in China by providing theoretical support for the selection of materials.In this paper, two kinds of materials, brass and low carbon steel, were used in marine engineering facilities under laboratory conditions by electrochemical experiment and corrosion morphology observation, respectively, in sulfate reducing bacteria and Pseudomonas aeruginosa.The corrosion behavior of oil-macrophage and its compound bacteria were studied under five different environmental conditions.The results showed that the corrosion of brass was accelerated by cathodic depolarization under the condition of single sulfate reducing bacteria, and the corrosion potential shifted negatively and the corrosion current density shifted positively with the increase of immersion time, which indicated that the corrosion was aggravated.In the environment of Pseudomonas aeruginosa, the microbial membrane had a certain inhibition effect on brass in the early stage of formation, but with the prolongation of soaking time,Corrosion inhibition effect of Pseudomonas aeruginosa on Brass the corrosion process of Q235 low carbon steel was weakened or even promoted. Due to cathodic depolarization, the corrosion of Q235 steel was promoted by cathodic depolarization, and a wide range of local corrosion occurred on the surface of the sample.In the early stage of corrosion of oil bacteria, the corrosion rate of low carbon steel was accelerated due to the difference of oxygen concentration, and the corrosion reaction was slowed down in the later stage, and the corrosion on the surface of the sample was relatively light, and brass was found in the solution of compound bacteria of sulfate reducing bacteria and Pseudomonas aeruginosa.The corrosion current density of brass is between the corrosion current density of single Pseudomonas aeruginosa and the corrosion current density of sulfate reducing bacteria in the solution of compound strain of sulfate reducing bacteria and Pseudomonas aeruginosa.The corrosion current density is less than the corrosion state of two single strains.The two results showed that Pseudomonas aeruginosa inhibited the growth of sulfate reducing bacteria, and the corrosion state of Q235 low carbon steel in oil-macrophage and sulfate reducing bacteria was similar to that in the earlier stage of corrosion of Pseudomonas aeruginosa.It was also indicated that oil-macrophage inhibited the growth of sulfate reducing bacteria.
【学位授予单位】：浙江海洋大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：Q93;P755.3

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