The effects of sulphate-reducing bacteria （SRB） on the 2205 duplex stainless steel in the sea water and oil industry environments were studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polar...The effects of sulphate-reducing bacteria （SRB） on the 2205 duplex stainless steel in the sea water and oil industry environments were studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polarization and microorganism analysis. The results showed that the detected SRB was the non-spore bacillus of about 0.8μm×（1.8--2.2）μm in size and the content of S was about 7. 59% in the corrosion products. SRB contributed to the corrosion evolution which caused the corrosion failure of 2205 duplex stainless steel pipe in the liquid hydrocarbon cooler. During the corrosion process, the produced H2S could significantly influence the anodic process and finally accelerate the corrosion. SEM observation indicated that the distribution of SRB on the surface of 2205 duplex stainless steel was nonuniform. X ray photoelectron spectroscopy analysis revealed that the surface film was composed of Cr2O3, MoO3 , FeS, FeS2, Fe（OH）2 and FeO after immersing the sample in the SRB medium for 14 d.展开更多
Microbiologically driven acidic pollution of coal gangue has become amajor environmental problem in coal gangue dumps in coal mining areas.Addition of bactericides and sulphate reducing bacteria(SRB)is an effective me...Microbiologically driven acidic pollution of coal gangue has become amajor environmental problem in coal gangue dumps in coal mining areas.Addition of bactericides and sulphate reducing bacteria(SRB)is an effective means to control the acidic pollution of coal gangue,but their mechanism of action has not been fully investigated.By adding bactericide,SRB and bactericide-SRB to the newly produced coal gangue,respectively,the effects of these treatments on the microbial community structure were observed.Changes in pH and electrical conductivity(EC)of the gangue leaching solution,as well as themicrobial community composition and functional abundance on the gangue surface were analysed by leaching simulation experiments and 16S rRNA sequencing.The results showed that(1)the addition of bactericide-SRB was the most effective treatment to elevate pH before 8 d,while the addition of SRB performed best after 22 d(2)The addition of bactericide and SRB drastically changed the microbial community structure on the gangue surface.Simultaneous addition of both had the best inhibitory effect on pathogenic bacteria and Thiobacillus.(3)All three treatments promote higher abundance of genes related to nitrogen cycling,but reflected in different gene functions.Microorganisms with sulfate respiration function in the experimental group all showed different increases.The abundance of other sulfur cycle genes decreased substantially.However,Human Pathogens All had higher abundance than control check(CK)in each treatment,whichmay indicate that the addition of either bactericides or SRB increases the risk of microbial pathogenicity to humans.展开更多
In this work, surface characterization and electrochemical measurement were employed to investigate the effects of magnetic field（MF） on the corrosion of Q235 carbon steel in a NaCl solution containing sulphate-redu...In this work, surface characterization and electrochemical measurement were employed to investigate the effects of magnetic field（MF） on the corrosion of Q235 carbon steel in a NaCl solution containing sulphate-reducing bacteria（SRB） or extracellular polymeric substances（EPS）. Results demonstrated that a 150 mT MF enhanced steel corrosion in a SRB-containing NaCl solution by 202% calculated from weight loss with pitting corrosion as the main corrosion type.Either EPS or MF rendered steel corrosion, but a synergistic interaction between MF and EPS boosted up steel corrosion.This synergistic enhancement could be referred to the alteration in orientation of EPS induced by MF. The presence of higher percentage of chloride ions on the carbon steel surface manifested that MF initiated the erosion of chloride ions on the carbon steel coupon.展开更多
基金Item Sponsored by National Natural Science Foundation of China(21276036,51101025)
文摘The effects of sulphate-reducing bacteria （SRB） on the 2205 duplex stainless steel in the sea water and oil industry environments were studied by electrochemical impedance spectroscopy （EIS）, potentiodynamic polarization and microorganism analysis. The results showed that the detected SRB was the non-spore bacillus of about 0.8μm×（1.8--2.2）μm in size and the content of S was about 7. 59% in the corrosion products. SRB contributed to the corrosion evolution which caused the corrosion failure of 2205 duplex stainless steel pipe in the liquid hydrocarbon cooler. During the corrosion process, the produced H2S could significantly influence the anodic process and finally accelerate the corrosion. SEM observation indicated that the distribution of SRB on the surface of 2205 duplex stainless steel was nonuniform. X ray photoelectron spectroscopy analysis revealed that the surface film was composed of Cr2O3, MoO3 , FeS, FeS2, Fe（OH）2 and FeO after immersing the sample in the SRB medium for 14 d.
文摘Microbiologically driven acidic pollution of coal gangue has become amajor environmental problem in coal gangue dumps in coal mining areas.Addition of bactericides and sulphate reducing bacteria(SRB)is an effective means to control the acidic pollution of coal gangue,but their mechanism of action has not been fully investigated.By adding bactericide,SRB and bactericide-SRB to the newly produced coal gangue,respectively,the effects of these treatments on the microbial community structure were observed.Changes in pH and electrical conductivity(EC)of the gangue leaching solution,as well as themicrobial community composition and functional abundance on the gangue surface were analysed by leaching simulation experiments and 16S rRNA sequencing.The results showed that(1)the addition of bactericide-SRB was the most effective treatment to elevate pH before 8 d,while the addition of SRB performed best after 22 d(2)The addition of bactericide and SRB drastically changed the microbial community structure on the gangue surface.Simultaneous addition of both had the best inhibitory effect on pathogenic bacteria and Thiobacillus.(3)All three treatments promote higher abundance of genes related to nitrogen cycling,but reflected in different gene functions.Microorganisms with sulfate respiration function in the experimental group all showed different increases.The abundance of other sulfur cycle genes decreased substantially.However,Human Pathogens All had higher abundance than control check(CK)in each treatment,whichmay indicate that the addition of either bactericides or SRB increases the risk of microbial pathogenicity to humans.
基金financially supported by the Shenzhen Strategic Emerging Industry Development Special Fund Project (No. JCYJ20130401144744190)the Innovation Foundation of Huazhong University of Science and Technology Innovation Institute (Nos. 2015TS150, 2015ZZGH010)
文摘In this work, surface characterization and electrochemical measurement were employed to investigate the effects of magnetic field（MF） on the corrosion of Q235 carbon steel in a NaCl solution containing sulphate-reducing bacteria（SRB） or extracellular polymeric substances（EPS）. Results demonstrated that a 150 mT MF enhanced steel corrosion in a SRB-containing NaCl solution by 202% calculated from weight loss with pitting corrosion as the main corrosion type.Either EPS or MF rendered steel corrosion, but a synergistic interaction between MF and EPS boosted up steel corrosion.This synergistic enhancement could be referred to the alteration in orientation of EPS induced by MF. The presence of higher percentage of chloride ions on the carbon steel surface manifested that MF initiated the erosion of chloride ions on the carbon steel coupon.
