材料研究学报, 2025, 39(2): 145-152 DOI: 10.11901/1005.3093.2023.602

研究论文

复配杀菌缓蚀剂对N80钢在SRB环境中微生物腐蚀行为的影响

胥聪敏,1, 李雪丽1, 付安庆2, 孙姝雯1, 陈志强1, 李城臣1

1 西安石油大学材料科学与工程学院 西安 710065

2 中国石油集团工程材料研究院有限公司 石油管材及装备材料服役行为与结构安全国家重点实验室 西安 710077

Effect of Compound Bactericidal Corrosion Inhibitor on Corrosion Behavior of N80 Steel at Different Temperatures

XU Congmin,1, LI Xueli1, FU Anqing2, SUN Shuwen1, CHEN Zhiqiang1, LI Chengchen1

1 School of Materials Science and Engineering, Xi'an Shiyou University, Xi'an 710065, China

2 State Key Laboratory for Performancce and Structure Safety of Petroleum Tubular Goods and Equipment Materials, CNPC Tubular Goods Research Institute, Xi'an 710077, China

通讯作者: 胥聪敏,教授,cmxu@xsyu.edu.cn,研究方向为金属腐蚀与防护

责任编辑: 吴岩

收稿日期: 2023-12-25   修回日期: 2024-03-04  

基金资助: 国家自然科学基金(51974245)
国家自然科学基金(21808182)
陕西省重点研发计划(2020GY-234)
西安石油大学材料科学与工程学院西安市高性能油气田材料重点实验室,陕西省高等学校重点实验室“油气田腐蚀防护与新材料”,西安石油大学研究生创新与实践能力培养项目(YCS22213138)

Corresponding authors: XU Congmin, Tel: 18092078500, E-mail:cmxu@xsyu.edu.cn

Received: 2023-12-25   Revised: 2024-03-04  

Fund supported: National Natural Science Foundation of China(51974245)
National Natural Science Foundation of China(21808182)
Shaanxi Province Key R&D Program Projects(2020GY-234)
Xi'an Key Laboratory of High Performance Oil and Gas Field Materials, School of Materials Science and Engineering, Xi'an Shiyou University, Corrosion protection and New Materials for Oil and Gas Fields in Key Laboratory of Higher Education in Shaanxi Province, Postgraduate Innovation and Practical Ability Training Program of Xi'an Shiyou University(YCS22213138)

作者简介 About authors

胥聪敏,女,1977年生,博士

摘要

采用生物培养技术、失重实验、电化学测试和表面分析等手段研究了硫酸盐还原菌(SRB)在不同温度对N80钢腐蚀行为的影响和在SRB环境中复配杀菌缓蚀剂对N80钢缓蚀性能的影响。结果表明,N80钢在不同温度的腐蚀速率与SRB的活性成正比,37 ℃活性最高的SRB使N80钢表面的极化电阻Rp最小,腐蚀最严重,腐蚀速率(0.03553 mm/a)最高,分别是20和50 ℃时的1.53倍和1.16倍。加入复配杀菌缓蚀剂使N80钢20和37 ℃的Rp值显著增大,腐蚀受到抑制,缓蚀率分别高达65.45%与64.79%。其原因是,复配杀菌缓蚀剂中的杀菌剂四羟甲基硫酸磷(THPS)中的亲油基团羟甲基进入细菌细胞膜改变了蛋白质的特性而使细菌死亡;增效渗透剂二甲基亚砜促进THPS的羟甲基进入细菌细胞膜内提高了杀菌效果;而杀菌增强剂D-络氨酸作为信号分子使生物膜分解脱落,破坏了浓差环境,使腐蚀减缓;缓蚀剂中的壳聚糖与Fe2+结合生成一层保护膜保护了基体,从而降低了腐蚀速率。N80钢在50 ℃的缓蚀率仅为0.26%,因为过高温度使缓蚀剂分子的运动加剧,使吸附在N80钢表面的分子解吸率提高和吸附膜解离,导致缓蚀率下降到极低。

关键词: 金属材料; 硫酸盐还原菌; 复配杀菌缓蚀剂; 生物膜; 腐蚀行为

Abstract

The effect of sulfate-reducing bacteria (SRB) on the corrosion behavior of N80 steel in SRB containing solution at 20, 37 and 50 oC, and for this case the effectiveness of a compound bactericidal corrosion inhibitor in the bactericidal effect and corrosion inhibition performance of N80 steel were comparatively investigated via biological culture technique, weightlessness measurement electrochemical testing, and surface analysis etc. The results showed that the corrosion rate of N80 steel was proportional to the SRB activity at different temperatures. The SRB activity was the highest at 37 oC, the polarization resistance Rp of N80 steel was the smallest, and the corrosion rate (0.03553 mm/a) was the largest, which was 1.53 times of that at 20 oC and 1.16 times of that at 50 oC, thus the corrosion was the most serious. However, after adding the compoundbactericidal corrosion inhibitor, the Rp value of N80 steel at 20 and 37 oC were increased significantly, and the corrosion of the steel was effectively inhibitedwith corrosion inhibitionefficiency of 65.45% and 64.79%, respectively. This is mainly due to that the lipophilic group hydroxymethyl of the bactericide tetrahydroxymethyl phosphate sulfate (THPS), as one of the components of the compound bactericide corrosion inhibitor, enters the bacterial cell membrane, changes its protein properties, then resulting in bacteria death; Meanwhile the dimethyl sulfoxide promotes the hydroxymethyl of THPS to enter the bacterial cell membrane and enhances the bactericidal effect. As a signal molecule, D-tyrosine, a bactericidal enhancer, promotes the decomposition of biofilm, destroys the surrounding concentration difference, thus slows down the corrosion. The Chitosan in the corrosion inhibitor combined with Fe2+ to produce a protective film to protect the substrate, thereby, reducing the corrosion rate. However, at 50 oC, the corrosion inhibition efficiency for N80 steel was only 0.26%, which is due to that the excessive temperature intensifies the movement of corrosion inhibitor molecular, increase in the molecular desorption rate adsorbed on the surface of N80 steel and the dissociates the adsorption film, resulting in a very low corrosion inhibition efficiency.

Keywords: metallic materials; sulfate-reducing bacteria (SRB); compound bactericidal corrosion inhibitor; biofilm; corrosion behavior

PDF (4780KB) 元数据 多维度评价 相关文章 导出 EndNote| Ris| Bibtex  收藏本文

本文引用格式

胥聪敏, 李雪丽, 付安庆, 孙姝雯, 陈志强, 李城臣. 复配杀菌缓蚀剂对N80钢在SRB环境中微生物腐蚀行为的影响[J]. 材料研究学报, 2025, 39(2): 145-152 DOI:10.11901/1005.3093.2023.602

XU Congmin, LI Xueli, FU Anqing, SUN Shuwen, CHEN Zhiqiang, LI Chengchen. Effect of Compound Bactericidal Corrosion Inhibitor on Corrosion Behavior of N80 Steel at Different Temperatures[J]. Chinese Journal of Materials Research, 2025, 39(2): 145-152 DOI:10.11901/1005.3093.2023.602

天然气中的页岩气是有机储集岩系中的非常规天然气,开采条件极为苛刻[1-3]。开采环境的复杂和恶劣使管线钢发生严重的腐蚀,如发生缝隙腐蚀、应力腐蚀开裂、微生物腐蚀(MIC)、以及多因素耦合腐蚀[4,5]。在页岩气的开采过程中,产出的水中有大量的微生物,包括硫酸盐还原菌(SRB)、乙酸菌和甲烷菌等。SRB是产生微生物腐蚀的主要细菌。Liu等[6]和Liao等[7]分别指出,SRB极易在X70管线钢和X65管线钢的管壁表面繁殖,生成的生物膜使管线钢发生严重的局部腐蚀。温度是影响MIC的重要因素,在不同温度下细菌的生物活性和代谢机制不同。页岩气田的温度甚至高于100 ℃,且随着油气田开采过程中工况深度的变化而变化[8]。Salgar-Chaparro等[9]发现,在不同温度发生MIC的程度不同,是生物代谢活性的不同所致。

用于减缓微生物腐蚀的传统杀菌剂用量大,造成严重环境污染和产生抗药性,为此国内外学者筛选出环保型杀菌剂[10]。一些D-氨基酸可在MIC中用作杀菌剂增强剂。在四羟甲基硫酸鳞(THPS)和环丙沙星中加入D-氨基酸增强剂可促进生物膜的分解,从而加强对SRB和铜绿假单胞菌(PA)的杀菌缓蚀作用[11,12]。N80钢是开采油气田使用的重要金属材料,研究其MIC极为必要。本文采用生物培养技术、杀菌过程评价、失重实验、电化学测试等手段,研究在不同温度下复配杀菌缓蚀剂对N80钢在SRB环境中微生物腐蚀行为的影响。

1 实验方法

1.1 试样的制备及菌种来源

实验用N80钢的化学成分为C 0.47,Mn 1.55,Si 0.25,S 0.008,P 0.015,Fe余量。将尺寸为50 mm × 25 mm × 2 mm的N80钢挂片试样用系列砂纸依次横纵打磨至1000#,用无水乙醇和丙酮冲洗后用吹风机冷风吹干,然后称其质量。将尺寸为10 mm × 10 mm × 2 mm的N80钢试样用环氧树脂和固化剂密封后风干,表面用砂纸横纵打磨至1000#后用无水乙醇冲洗并吹干。

实验用复配杀菌缓蚀剂的主要成分:THPS、D-络氨酸、二甲基亚砜和壳聚糖。将取自国内某油田的实验菌种富集培养、分离和提纯,鉴定表明其为SRB脱硫弧菌属(Desulfovibrio sp)。

1.2 细菌数的测定

用绝迹稀释法(MPN)测定溶液中的SRB菌数。将待测溶液接种并逐级稀释至10-7,在温度为37 ℃的生化培养箱中培养14 d后进行阳性反应读数,根据国家标准(GB/T14643.5-2009)[13]得到溶液中SRB的细菌浓度,复配杀菌缓蚀剂对SRB的杀菌率为

SRB bactericidal rate=(nWithout-nWith)/nWithout×100%

式中nWithout为不添加杀菌剂时培养14 d测得的细菌浓度(cell/mL);nWith为添加杀菌剂后培养14 d测得的细菌浓度(cell/mL)。根据SY/T5523-2016[14]测定SRB溶液中的S2-,得到SRB产生的S2-含量。

1.3 测定腐蚀速率和缓蚀率

实验中用美国石油协会(API)的标准培养基(GB/T14643.6-2009)[13]培养SRB。将配置好的培养基和广口瓶在121 ℃灭菌20 min,然后置于无菌操作台上冷却。在2个灭菌后容积为125 mL的无菌密封瓶中加入114 mL的SRB培养基和6 mL的SRB,放入3组平行试样。其中一组加入复配杀菌缓蚀剂;另一组作为对照实验放入20 ℃的培养箱中,在37和50 ℃处理,方式同上。浸泡14 d后取出,其腐蚀速率v (mm/a)为

v=8.76×104(m-m0)Aρt

式中:m0为腐蚀试验前试片的原始质量(g);m为腐蚀实验后去除腐蚀产物的试片质量(g);A为试片的表面积(cm2);ρ为试片的密度(g/cm3);t为腐蚀时间(h)。

为了研究复配杀菌缓蚀剂对N80钢腐蚀行为的影响,根据相关腐蚀速率和计算出复配杀菌缓蚀剂对N80钢的缓蚀率(η)为

η=(vWithoutvWith) / vWithout×100%

式中vWithout为不添加杀菌剂时的腐蚀速率,vWith为添加杀菌剂时的腐蚀速率。

1.4 电化学阻抗谱(EIS)的测定

在2个灭菌后容积为500 mL的无菌密封瓶瓶中加入475 mL的SRB培养基和25 mL的SRB,再分别放入2个平行试样,后续实验的分组和实验环境与细菌数的测定实验相同。使用三电极体系进行电化学实验:在不同温度下腐蚀14 d尺寸为10 mm × 10 mm × 2 mm的N80试样为工作电极,饱和甘汞电极为参比电极,铂电极为辅助电极。使用M2273电化学测试系统进行实验,EIS的测试频率范围为10-2~105 Hz,正弦波幅值为10 mV。

1.5 试样腐蚀产物的表面形貌观察

将腐蚀14 d的N80钢试样(表面附着生物膜)先在5%的戊二醛溶液中固定30 min,然后用无水乙醇逐级脱水和干燥;用扫描电子显微镜(SEM,TESCAN MAIA3LMH)观察试样腐蚀产物的表面形貌,用配套的电子能谱(EDS)仪分析腐蚀产物的成分,用X射线衍射仪分析腐蚀产物的物相。

2 结果和讨论

2.1 SRB的细菌浓度

图1给出了SRB分别为在25、37和50 ℃培养14 d的SRB细菌浓度和硫化物含量。表1列出了复配杀菌缓蚀剂在25、37和50 ℃对SRB的杀菌率。由图1可见,在不同温度培养14 d后SRB的细菌浓度高低的排序为37 ℃ > 50 ℃ > 20 ℃。这表明,在37 ℃ SRB的生长繁殖最好,活性最高,细菌浓度约为20 ℃时的3倍,50 ℃时的1.5倍;而20 ℃时SRB数量最少,活性最低。SRB以SO42-为电子受体将其还原成腐蚀性S2-,S2-与基体反应生成FeS,FeS固着在基体表面形成锈瘤,锈瘤下缺氧的基体成为阳极,无产物覆盖的基体成为阴极,形成的氧浓差电池使腐蚀加速。S2-含量与SRB活性成正比,SRB活性越高S2-含量越高则材料腐蚀越严重。

图1

图1   SRB在不同温度生长14 d的细菌浓度和硫化物含量

Fig.1   Bacterial concentration and sulfide content of SRB grown at different temperatures for 14 d


表1   复配杀菌缓蚀剂在不同温度下对SRB的杀菌率

Table 1  Bactericidal rate of SRB at different temperature with compound bactericidal corrosion inhibitor

Temperature20 oC37 oC50 oC
SRB bactericidal rate92.05%99.00%49.05%

新窗口打开| 下载CSV


这表明,温度决定了SRB的生长速度和代谢活动,温度过高和过低都抑制SRB的生长。因此,本文实验中使用中温SRB,37 ℃是最适宜的生长温度,生长代谢速度最高。由表1可见,在20和37 ℃复配杀菌缓蚀剂对SRB杀菌率均达到90%以上,表明杀菌效果显著;而50 ℃时的杀菌率仅为49.05%。其原因是,在过高的温度下溶液中的分子运动加快,使缓蚀剂分子的解吸率提高和壳聚糖中的N、O、S元素与Fe2+生成的保护性吸附膜解离。

2.2 失重分析

将N80钢分别在20、37、50 ℃腐蚀挂片,其中一组加入复配杀菌缓蚀剂,另一组不加入复配杀菌缓蚀剂,在SRB溶液中浸泡14 d后的质量损失和η分别在图2表2中给出。

图2

图2   N80钢在不同温度的SRB溶液中腐蚀14 d后的质量损失

Fig.2   Mass loss and corrosion inhibition rate of N80 steel corroded in SRB solution at different temperatures for 14 d


表2   复配杀菌缓蚀剂对N80钢在不同温度下的缓蚀率

Table 2  Corrosion inhibition rate of N80 steel at different temperatures with compound bactericidal corrosion inhibitor

Temperature20 oC37 oC50 oC
Corrosion inhibition rate (η)65.45%64.79%0.26%

新窗口打开| 下载CSV


图2表2可见,N80钢在不同温度的SRB溶液中腐蚀14 d腐蚀速率高低的排序为:37 ℃(0.03553 mm/a,中度腐蚀) > 50 ℃ (0.03062 mm/a,中度腐蚀) > 20 ℃ (0.02316 mm/a,轻度腐蚀)。由此可见:在37 ℃腐蚀最严重,在50 ℃次之,在20 ℃腐蚀最轻。其原因是:SRB在37 ℃活性最高,适合其生长繁殖;SRB在20 ℃活性最低,生长繁殖受到抑制。这些结果,与图1给出的结果一致。加入复配杀菌缓蚀剂后,N80钢在37 ℃的腐蚀速率由0.03553 mm/a(中度腐蚀)降低到0.01251 mm/a(轻度腐蚀),η为64.79%,在20 ℃降低到了65.45%。而添加复配杀菌缓蚀剂后N80钢在50 ℃时的年腐蚀深度几乎不变,η仅为0.26%。其原因是,在过高的温度下激烈的热运动打破了杀菌缓蚀剂中分子的平衡,杀菌缓蚀性能的降低影响了杀菌缓蚀效果。

2.3 电化学阻抗谱

图3给出了N80钢在不同温度的SRB溶液中腐蚀14 d的Nyquist、Bode以及拟合曲线。无复配杀菌缓蚀剂时,不同温度下容弧抗半径大小的排序为37 ℃ < 50 ℃ < 20 ℃。容抗弧半径越小表明N80钢的腐蚀越严重,与质量损失和SRB计数结果吻合。加入复配杀菌缓蚀剂后N80钢在37和20 ℃的容抗弧半径显著变大,最大相位角向高频移动。这表明,此时N80钢基体表面的生物膜疏松,复配杀菌缓蚀剂的效果好。但是,50 ℃的容抗弧半径反而变小,最大相位角几乎不变。其原因是,过高的温度在复配杀菌缓蚀剂中引入了其他离子,促进了N80钢的溶解。这表明,温度对SRB引起的腐蚀有重要的影响。

图3

图3   N80钢在不同温度SRB溶液中腐蚀14 d后的Nyquist、Bode以及拟合曲线

Fig.3   N80 corrodes 14 d EIS of (a) Nyquist plots, (b, c) Bode plots in SRB solutions at different tem-peratures


表3列出了阻抗谱对应的等效电路和相应的拟合参数(误差在10%以内),图4给出了拟合所用的等效电路,其中Rs为溶液电阻,Rf为腐蚀产物膜电阻,Rct为电荷转移电阻,Qf为腐蚀产物膜电容,Qdl为双电层电容;C为电容,与电学中的纯电容相同[15]。在阻抗拟合中用常相位角元件Qdl代替电容元件C,因为弥散效应导致双电层充放电不均匀[16]nf (取0~1)为弥散系数,代表电极表面的粗糙程度和腐蚀电流不均匀的程度,nf越小弥散效应越强[15]

表3   N80在不同温度SRB溶液中腐蚀14 d的EIS拟合结果

Table 3  EIS fitting results of 14 d corrosion of N80 in SRB solution at different temperatures

TemperatureRsYfnfRfYdlndlRctWEquivalent circuit
Without adding compound bactericidal corrosion inhibitor
20 oC16.246.14 × 10-31.0042.197.716 × 10-20.977756.3-Fig.4a
37 oC16.369.30 × 10-20.95361.91.054 × 10-20.699.43-Fig.4a
50 oC10.085.16 × 10-41.00447.94.689 × 10-41.00307.4-Fig.4a
Adding compound bactericidal corrosion inhibitor
20 oC19.812.98 × 10-31.00192.31.256 × 10-30.872960-Fig.4a
37 oC19.761.69 × 10-31.0099372.50 × 10-30.8610.11-Fig.4a
50 oC19.136.42 × 10-40.91482.21.747 × 10-30.8850.363.75 × 10-3Fig.4b

新窗口打开| 下载CSV


图4

图4   EIS数据拟合的等效电路模型

Fig.4   Equivalent circuit model of EIS data fitting


表3可见,在20和37 ℃加入复配杀菌缓蚀剂后,Yf都有不同程度的减小。Yf减小说明电极表面膜减小和Rct增大,表明电荷转移受到阻碍。其原因是,杀菌剂THPS使SRB代谢产物减少和杀菌增强剂D-络氨酸促进了生物膜解体,使N80钢的表面腐蚀程度降低。但是在50 ℃加入复配杀菌缓蚀剂后Yf没有变小的趋势,Rct和电荷转移阻碍减小且nf值偏离1。这表明,此时N80钢表面腐蚀产物膜堆积、表面粗糙,腐蚀电流不均匀的程度提高和腐蚀严重。

图5给出了N80钢在不同温度的SRB溶液中腐蚀14 d后的Rp-1图。极化电阻Rp = Rf + RctRp-1可用于腐蚀速率评价,Rp-1与腐蚀电流呈正比,Rp-1的值越大表明N80钢腐蚀越严重。从图5可以看出,在不同温度下没有复配杀菌缓蚀剂时Rp-1大小的排序为:37 ℃ > 50 ℃ > 20 ℃。由此可见,37 ℃时Rct的值最小,电荷转移阻碍小,SRB的活性最高,表明腐蚀最严重。加入复配杀菌缓蚀剂后,20和37 ℃时的Rp-1值减小且Rct的值增大,电荷转移困难,使N80钢的腐蚀缓解;而温度提高到50 ℃反而促进了N80钢的腐蚀,因为过高的温度使分子热运动加快,加速了N80钢的腐蚀;也可能是分子解析效率提高,使杀菌缓蚀剂不起作用。

图5

图5   N80钢在不同温度的SRB溶液中腐蚀14 d后的Rp-1

Fig.5   N80 steel corroded Rp-1 after 14 d in SRB solution at different temperatures


2.4 N80钢腐蚀后的表面形貌

图6给出了N80钢在不同温度的SRB溶液中腐蚀14 d的SEM照片和EDS图。根据代谢腐蚀产物理论[17],在厌氧条件下SRB代谢生成活性较高且挥发性强的磷化物,与基体反应促进基体溶解,提高了腐蚀速率。由图6可以看出,没有复配杀菌缓蚀剂时N80钢在37 ℃的腐蚀产物膜最厚,完全覆盖了基体表面。这表明,此时的SRB生长活性最好。但是在高倍下可见其上有大量裂缝,使溶液中的P2-和Cl-从裂缝处进入膜内引起基体表面的电子发生转移,进一步促进N80钢发生点蚀。同时,37 ℃时P2-、Cl-和Ca2+的含量最高。这个结果与该温度下N80钢腐蚀最严重的结果吻合,而在另外两个温度下腐蚀性的产物含量都有所降低。加入复配杀菌缓蚀剂后,N80钢表面腐蚀产物膜的厚度显著减小且分布不均匀,部分基体表面裸露,在高倍镜下可见腐蚀产物膜疏松(在37 ℃尤为明显),且介质中的腐蚀性离子Cl-与SRB代谢生成的P2-和S2-的含量显著降低。这表明,复配杀菌缓蚀剂对SRB有很好的生长抑制和杀菌作用,能杀灭微生物膜下的SRB,对N80钢有很好的缓蚀作用。

图6

图6   N80钢在不同温度SRB溶液中腐蚀14 d后的SEM照片和EDS图

Fig.6   SEM and EDS images of N80 steel corroded in SRB solution at different temperatures for 14 d (a) no bactericidal at 20 oC; (b) no bactericidal at 37 oC; (c) no bactericidal at 50 oC; (d) with bactericidal at 20 oC; (e) with bactericidal at 37 oC; (f) with bactericidal at 50 oC


图7给出了N80钢在SRB溶液中腐蚀14 d后腐蚀产物的XRD谱。可以看出,N80钢在SRB中的腐蚀产物主要有FeOOH、Fe2O3、FeS和CaCO3,其含量分别为37.8%、32.9%、16.1%和13.2%。其中Ca2+与CO32-反应生成的CaCO3沉淀与其他产物吸附在产物膜上生成不均匀腐蚀产物膜,从而导致局部腐蚀。

图7

图7   N80钢在SRB溶液中腐蚀14 d后的XRD谱和腐蚀产物的含量

Fig.7   XRD pattern and corrosion product content of N80 steel after 14 d corrosion in SRB solution


3 讨论

从SEM照片和EDS可见,SRB生长代谢产生了大量的硫化物和磷化物。根据代谢腐蚀产物理论[17],SRB产生的H2S与溶液介质中的磷酸盐等发生反应生成磷化物。硫化物和磷化物与基体发生进一步反应,促进了基体的溶解。根据质量损失和细菌计数,温度是影响SRB生长代谢的重要因素。对于中温SRB,适宜的生长温度为30~37 ℃,其活性越高则腐蚀性越强。

加入复配杀菌缓蚀剂后,杀菌剂THPS中的羟甲基破坏浮游态细菌的细胞膜和蛋白质而抑制酶活性,使金属表面的细菌死亡;杀菌增强剂D-络氨酸作为信号分子与SRB蛋白质结合使生物膜分解脱落和氧浓差降低,减缓了基体腐蚀;增效渗透剂二甲基亚砜对亲水性和亲脂性基团有促渗作用且使其起效迅速,因此能促进THPS的亲油基团羟甲基渗透进入SRB细胞膜内,有利于杀菌剂发挥作用;缓蚀剂壳聚糖中的N、O、S元素继续与基体表面的Fe2+结合生成一层新的保护膜[18],减轻了N80钢的腐蚀。这表明,在37和20 ℃腐蚀速率降低,硫化物和磷化物大量减少。但是在50 ℃腐蚀速率仍然较高,因为温度超过了最佳温度,此时分子运动加快使吸附在N80钢表面的分子解吸效率提高[19,20]。同时,温度的提高也加速了N80钢的溶解,降低了缓蚀效果。结合XRD谱的产物分析可知,在SRB环境中溶液中的碳源和脂肪源为SRB提供能量,使SRB生长繁殖。同时,SRB以SO42-为电子受体,依靠碳源提供能量,使SO42-还原成H2S气体[21]

CH3CHOHCOO-+H2OCH3COO-+
CO2+4H++4e-
SO42-+8H+S2-+4H2O
S2-+2H+H2S

代谢产生的S2-与Fe2+发生反应生成FeS且附着在基体表面形成锈瘤,锈瘤下的基体缺氧从而成为阳极,加剧了点蚀的发生,不稳定的Fe2+又氧化成Fe3+而生成Fe2O3

Fe2++S2-FeS
Fe2++2OH-Fe(OH)2
4Fe(OH)2+O24FeOOH+2H2O
4Fe(OH)2+O2+2H2O4Fe(OH)3
2Fe(OH)3+nH2OFe2O3·nH2O+3H2O

4 结论

(1) 在不同温度下SRB生物活性的不同使N80钢的MIC行为不同,腐蚀速率与SRB的生长活性成正比。37 ℃时SRB生长繁殖的状态最佳,S2-含量最高,使腐蚀速率最高、腐蚀最严重。

(2) 复配杀菌缓蚀剂在37和20 ℃时的η分别达到了64.79%和65.45%,杀菌效果显著;过高的温度使缓蚀剂分子的解吸率提高、壳聚糖中的N、O、S元素与Fe2+生成的吸附膜解离,使缓蚀率和对SRB的杀菌率降低。

(3) 复配杀菌缓蚀中的杀菌增强剂D-酪氨酸使固着态生物膜发生脱落和氧浓差梯度减小,使腐蚀速率显著降低和杀菌剂THPS使SRB失去活性。增效渗透剂二甲基亚砜使THPS加速进入细菌细胞膜内提高杀菌作用。缓蚀剂壳聚糖与Fe2+生成的新保护膜使材料不易发生腐蚀。

(4) SRB代谢产生的硫化物、磷化物与N80钢基体发生腐蚀反应,以及腐蚀产物附着在基体表面形成的阴极与钢基体阳极形成氧浓差电池,促进点蚀的发生。

参考文献

Feng S Q, Li Y C, Liu H M, et al.

Microbiologically influenced corrosion of carbon steel pipeline in shale gas field produced water containing CO2 and polyacrylamide inhibitor

[J]. J. Nat. Gas Sci. Eng., 2020, 80: 103395

[本文引用: 1]

Zheng L, Cheng S K, Han Y Z, et al.

Bio-natural gas industry in China: current status and development

[J]. Renew. Sustain. Energy Rev., 2020, 128: 109925

Liu H X, Jin Z Y, Liu H F, et al.

Microbiological corrosion acceleration of N80 steel in shale gas field produced water containing Citrobacter amalonaticus at 60 oC

[J]. Bioelectrochemistry, 2022, 148: 108253

[本文引用: 1]

Shi L, Luo K, Wang J G, et al.

Failure analysis of an offshore drilling casing under harsh working conditions

[J]. Eng. Fail. Anal., 2021, 120: 105018

[本文引用: 1]

Wang H, Zhao W L, Shu Z H, et al.

Failure analysis of casing dropping in shale oil well during large scale volume fracturing

[J]. Eng. Fail. Anal., 2020, 118: 104849

[本文引用: 1]

Liu T, Cheng Y F, Sharma M, et al.

Effect of fluid flow on biofilm formation and microbiologically influenced corrosion of pipelines in oilfield produced water

[J]. J. Pet. Sci. Eng., 2017, 156: 451

[本文引用: 1]

Liao W Z, Yuan J T, Wang X D, et al.

Under-deposit microbial corrosion of X65 pipeline steel in the simulated shale gas production environment

[J]. Int. J. Electrochem. Sci., 2023, 18: 100069

[本文引用: 1]

Yang S, Lai F P, Li Z P, et al.

The effect of temperature on flowback data analysis in shale gas reservoirs: a simulation-based study

[J]. Energies, 2019, 12: 3751

[本文引用: 1]

Salgar-Chaparro S J, Lepkova K, Pojtanabuntoeng T, et al.

Microbiologically influenced corrosion as a function of environmental conditions: a laboratory study using oilfield multispecies biofilms

[J]. Corros. Sci., 2020, 169: 108595

[本文引用: 1]

Xu C M, Zhang J R, Zhu W S, et al.

Effect of D-amino acids on corrosion behavior of different steels due to mixed bacteria

[J]. Chin. J. Mater. Res., 2023, 37(12): 924

DOI      [本文引用: 1]

The effect of biocide and D-amino acid on the corrosion behavior of 20# carbon steel, N80 steel and P110 steel in the media of SRB+IOB mixed bacteria, was comparatively assessed by using weight loss method, electrochemical measurements and SEM. In the tests without biocide, P110 suffered from severe corrosion with weight loss of 0.278 mm/a, while weight loss of 20# and N80 were 0.149 and 0.148 mm/a respectively, while uniform and dense biofilms with deposited corrosion products formed on the surface of all the steels; in the tests with biocide, the corrosion of the three steels slowed down, it is found that the formed rust scales on the surface of steels with significantly lower content of Ca Mg, P, and S, but with cracks and spallation steels. The electrochemical measurement results also revealed that the corrosion rate of three steels was significantly reduced when they were immersed for 14 d in the corrosive media with addition of biocides. The corrosion mechanism of SRB and IOB mixed bacteria is probably due to that SRB oxidizes Fe to Fe2+ through its own metabolism, and Fe2+ is further oxidized by IOB to Fe3+, and IOB provides environmental conditions for SRB so as to form a synergistic effect. It is proposed that D-amino acids and biocide effectively inhibit MIC behavior by regulating the bacterial gene expression and destroys the cell structure, as well as the oxygen concentration difference environment. Due to the different content of C, Cu and others, the corrosion rate of the three steels may be different under the sterile conditions.

胥聪敏, 张津瑞, 朱文胜 .

D-氨基酸对不同钢材混合菌腐蚀行为的影响

[J]. 材料研究学报, 2023, 37(12): 924

DOI      [本文引用: 1]

研究了杀菌剂与D-氨基酸对20#碳钢、N80钢以及P110钢在硫酸盐还原菌(SRB)+铁氧化菌(IOB)混合菌腐蚀过程中的影响作用,利用失重与电化学测量以及扫描电镜(SEM)对腐蚀形貌分析等初步探索了D-氨基酸的杀菌缓蚀增强机理。无杀菌剂组中P110发生严重腐蚀(0.278 mm/a),20#与N80腐蚀速率较低(为0.149、0.148 mm/a),所有试样表面有均匀且致密的生物膜以及腐蚀产物堆积;有杀菌剂组中三种钢材腐蚀程度减缓,腐蚀产物膜发生龟裂、剥离,其中Ca、Mg、P以及S含量明显减少。在添加杀菌剂溶液中浸泡14 d后,三种钢材的腐蚀速率明显降低。有无杀菌剂下,三种钢材耐蚀性由优到差排序均为N80&gt;20#&gt;P110。SRB和IOB混合菌的腐蚀机制可能是由于SRB通过自身代谢将基体Fe氧化为Fe<sup>2+</sup>,Fe<sup>2+</sup>又被IOB进一步氧化为Fe<sup>3+</sup>且IOB为SRB提供环境条件形成了协同作用。D-氨基酸和杀菌剂通过调控细菌基因表达、破坏细胞结构、氧浓差环境等方式有效的抑制微生物腐蚀(MIC)行为。三种钢材由于C、Cu等元素含量不同,使得三种钢材在无菌条件下腐蚀速率有所差异。

Jia R, Yang D Q, Li Y C, et al.

Mitigation of the Desulfovibrio vulgaris biofilm using alkyldimethylbenzylammonium chloride enhanced by D-amino acids

[J]. Int. Biodeterior. Biodegrad., 2017, 117: 97

[本文引用: 1]

Unsal T, Wang D, Kumseranee S, et al.

D-Tyrosine enhancement of microbiocide mitigation of carbon steel corrosion by a sulfate reducing bacterium biofilm

[J]. World J. Microbiol. Biotechnol., 2021, 37: 103

[本文引用: 1]

Liu H W, Fu C Y, Gu T Y, et al.

Corrosion behavior of carbon steel in the presence of sulfate reducing bacteria and iron oxidizing bacteria cultured in oilfield produced water

[J]. Corros. Sci., 2015, 100: 484

[本文引用: 2]

Shang T, Tian J C, Liu X, et al.

Genesis analysis of the petroleum associated H2S: a case study of Pengyang oilfield in Ordos Basin

[J]. Acta Petrol. Sin., 2022, 43(5): 595

[本文引用: 1]

尚 婷, 田景春, 刘 鑫 .

石油伴生H2S的成因分析——以鄂尔多斯盆地彭阳油田为例

[J]. 石油学报, 2022, 43(5): 595

[本文引用: 1]

Gateman S M, Gharbi O, de Melo H G, et al.

On the use of a constant phase element (CPE) in electrochemistry

[J]. Curr. Opin. Electrochem., 2022, 36: 101133

[本文引用: 2]

Xu C M, Wang W Y, Liu L, et al.

The inhibition effect of D-amino acid on the microbial corrosion of mixed bacteria

[J]. Nat. Gas Ind., 2021, 41(2): 160

[本文引用: 1]

胥聪敏, 王文渊, 刘 利 .

D-氨基酸对混合菌生物腐蚀的缓蚀行为影响分析

[J]. 天然气工业, 2021, 41(2): 160

[本文引用: 1]

Tang H Q, Guo Z H, Zhang J H, et al.

Effects of sulfate reducing bacteria on anaerobic corrosion of mild steel

[J]. J. Chin. Soc. Corros. Prot., 1991, 11(1): 46

[本文引用: 2]

唐和清, 郭稚弧, 张君华 .

硫酸盐还原菌对碳钢腐蚀的影响

[J]. 中国腐蚀与防护学报, 1991, 11(1): 46

[本文引用: 2]

采用失重法,极化曲线法和 SEM 研究了硫酸盐还原菌(SRB)诱导碳钢腐蚀的主要因素。实验结果表明,在 SRB 的代谢过程中,会产生一种挥发性的含磷化合物,它具有一定的腐蚀性,但导致碳钢腐蚀的主要因素是代谢产物中的硫化物,特别是硫化氢,以及在介质中可能大量存在的 Fe~(2+),它们对腐蚀电化学过程有明显的去极化作用。

Liu H, Du Y M, Wang X H, et al.

Chitosan kills bacteria through cell membrane damage

[J]. Int. J. Food Microbiol., 2004, 95(2): 147

PMID      [本文引用: 1]

The bactericidal activity of chitosan (CS) acetate solution against Escherichia coli and Staphylococcus aureus was evaluated by the enumeration of viable organisms at different incubation times. Morphologies of bacteria treated with CS were observed by transmission electron microscopy (TEM). The integrity of the cell membranes of both species and the permeabilities of the outer membrane (OM) and inner membrane (IM) of E. coli were investigated by determining the release from cells of materials that absorb at 260 nm, changes in the fluorescence of cells treated with the fluorescent probe 1-N-phenylnaphthylamine (NPN) and release of cytoplasmic beta-galactosidase activity. In addition, the interaction of CS with synthetic phospholipid membranes was studied using gel permeation chromatography (GPC), UV-VIS spectrophotometery, Fourier-transform infrared spectroscopy (FT-IR) and thermal analysis. Results showed that CS increased the permeability of the OM and IM and ultimately disrupted bacterial cell membranes, with the release of cellular contents. This damage was likely caused by the electrostatic interaction between NH(3)(+) groups of CS acetate and phosphoryl groups of phospholipid components of cell membranes.

Song D, Yu W, Yang H.

Scale and corrosion inhibition performance of carboxymethyl chitosan

[J]. Sci. Sin. Chim., 2021, 51(5): 566

[本文引用: 1]

宋 荻, 余 伟, 杨 琥.

羧甲基壳聚糖阻垢缓蚀性能研究

[J]. 中国科学: 化学, 2021, 51(5): 566

[本文引用: 1]

Tan F N, Pang X H, Sui W P, et al.

The mechanism and inhibition effect on chitosan for mild steel in 1 mol/L HCl

[J]. Mar. Sci., 2011, 35(7): 40

[本文引用: 1]

谭福能, 庞雪辉, 隋卫平 .

壳聚糖在1 mol/L HCl中对Q235碳钢的缓蚀性能及机理研究

[J]. 海洋科学, 2011, 35(7): 40

[本文引用: 1]

Xu C M, Gao H R, Zhu W S, et al.

Study on the behavior and mechanism of D-amino acid dispersing biofilm

[J]. Mater. Rep., 2023, 37(1): 243

[本文引用: 1]

胥聪敏, 高豪然, 朱文胜 .

D-氨基酸驱散生物膜的行为与作用机理研究

[J]. 材料导报, 2023, 37(1): 243

[本文引用: 1]

/