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Microbiologically‐influenced corrosion (MIC) is extremely harmful to both the industry and the environment. Sulfate‐reducing bacteria (SRB) are also important: we have to know what they really are and what they really do to us; this means we have to improve our understanding of SRB and their characteristics. MIC is the officially accepted terminology by NACE[1] to address this type of corrosion. It is a kind of corrosion in which effects of certain microorganisms are felt. MIC is still a matter open for discussion: we cannot explain what is really meant by “microbiological” component, i.e. does it express the possibility that some microbial activity observed at corroded sites on metal surfaces may not result from bacterial growth on metal, but rather that chemical or electrochemical attack on the metal may provide a favorable niche for bacteria to grow? Nor can we be sure about our understanding of the importance of working mechanisms and even the types of microorganisms involved in MIC. In order to have a deeper understanding about corrosion caused by sulfate‐reducing bacteria (SRB), we have to know more about SRB themselves. So, after discussing the importance of MIC, we will mainly focus on SRB and their characteristics that may be new and interesting to the reader.

Sulfate-reducing bacteria (SRB) are recognized by scholars as the most important class of bacteria leading to corrosion of metal materials. It is important to use the properties of microorganisms to inhibit the growth of SRB in the corrosion protection of metal materials and to protect the environment.

In this work, the behavior of anaerobic Thiobacillus denitrificans (TDN) intracellular enzyme inhibition of SRB corrosion of EH36 steel was investigated with electrochemical impedance spectroscopy, biological detection technology and X-ray photoelectron spectroscopy.

Results showed that the SRB crude intracellular enzyme affected the corrosion behavior of EH36 steel greatly and the purified TDN intracellular enzyme inhibits SRB intracellular enzyme corrosion to EH36 steel.

A perfect enzyme activity inhibition mechanism will provide theoretical guidance for the selection and application of anticorrosion microorganisms, which is of scientific significance in the field of microbial anticorrosion research.

This paper deals with the causes and mechanisms of internal corrosion of tanks used for the storage of crude oil and distillates. Services which are considered in this paper include crude oil storage tanks, gasoline blending and/or storage tanks and storage tanks for kerosene and heavier distillates. Fixed‐roof, as well as floating‐roof tanks, are considered. Methods for corrosion prevention and control are discussed.

Investigates anaerobic two‐stage treatment of tannery wastewater. This results in a mean chemical oxygen demand (COD) removal of 60 per cent for tannery B and more than 70 per cent for tanneries A and C with COD_o = 5,710mg l^‐1 and mean detention time held at 3.5 days. Gas production was small, rating an estimated 75 l kg‐1 COD_o with COD_o = 5,710mg l^‐1. Tests simultaneously the influence of quality and quantity of wastewater on COD removal and gas production (multiple regression). Finds significant inhibitory effects were caused by chloride on gas volume and by sulphate on COD removal. Chromium showed no significant effect. Dosage of ferric chloride for removal of the toxic sulphide effected a decrease in gas volume and had no effect on COD removal (analysis of variance).

The purpose of this paper is to study the metal-Microbe interaction playing a crucial role in microbiologically influenced corrosion (MIC) and biofouling of materials in cooling water systems. Treatment regimens should be planned based on this understanding.

Attempts were made in the past decades to characterize and understand biofilm formation on important power plant structural materials such as carbon steel (CS), stainless steel (SS) and titanium in fresh water and in seawater to achieve better control of biofouling and minimize MIC problems.

This report presents the results of detailed studies on tuberculation-formed CS because of the action of iron-oxidizing bacteria and the effects of algae- and bacteria-dominated biofilms on the passivity of SS. The preferential adhesion of different bacterial species on SS under the influence of inclusions and sensitization was studied in the context of preferential corrosion of SS weldments due to microbial action. Detailed characterization of biofilms formed on titanium (the likely condenser material for fast breeder reactors) after exposure for two years in Kalpakkam coastal waters revealed intense biofouling and biomineralization of manganese even in chlorinated seawater. Studies on the effectiveness of conventional fouling control strategies were also evaluated.

The detailed studies of different metal/biofilm/microbe interactions demonstrated the physiological diversity of microbes in the biofilms that were formed on different materials, coupling their cooperative metabolic activities with consequent corrosion behaviour. These interactions could enhance either anodic or cathodic reactions and exploit metallurgical features that enhance biofilm formation and/or the capacity of microbes to mutate and overcome mitigation measures.

Bacterial action often constitutes a major cause of corrosion in petroleum refineries and similar plant. The problem occurs in three major areas: in underground structures, in cooling water systems and in storage facilities for both crude and refined petroleum products. What are the factors upon which bacterial corrosion depends and what are the remedies?

The purpose of this study is to find the multi-factor influence law of stress, strain rate and sulfate-reducing bacteria (SRB) on X70 pipeline steel in a simulated solution of sea mud and the order of influence of the three factors on X70 steel to develop a scientific basis for pipeline corrosion protection.

This paper studied the effects of stress, strain rate and SRB on the X70 pipeline steel corrosion behavior in simulated sea mud solution through orthogonal testing, electrochemical experiments and morphological observations.

The results of this study showed that stress proved to be the most relevant element for corrosion behavior, followed by SRB and strain rate. At high stresses (301 MPa and 576 MPa), stress dominated the corrosion behavior of X70 pipeline steel. However, at low stress (82 MPa), SRB played the most important role.

Subsea pipelines are in a very complex environmental regime that includes stress, strain rates and SRB, which often cause pipeline pitting and perforation. However, most scholars have only looked into the influence of single factors on metal corrosion. So, the single-factor experimental results of previous studies could hardly be applied to actual working conditions. There is an urgent need to understand the multi-factor influence law of stress, strain and SRB acting together on the pipeline corrosion behavior, especially to determine the dominant factor.

Bdellovibrio bacteriovorus is a gram-negative predatory bacterium which can potentially inhibit microbiologically influenced corrosion by preying on sulfate-reducing bacteria (SRB). However, no researches about the inhibition are reported according to the authors’ knowledge. The purpose of this paper was to investigate the Inhibition effect of B. bacteriovorus on the corrosion of X70 pipeline steel induced by SRB.

The effect of B. bacteriovorus on the growth of SRB was studied by measuring the optical density at 600 nm (OD600) and sulfate concentration in culture medium. X70 pipeline steel was used as the test material to investigate the anti-corrosion effect of B. bacteriovorus on SRB by conducting electrochemical analysis (including Tafel polarization curves and electrochemical impendence spectroscopy) and weight loss measurement.

B. bacteriovorus could inhibit the growth of SRB in culture medium by its predation on SRB, which led to decrease of OD600 value and increase of sulfate concentration. The results of electrochemical analysis indicated that B. bacteriovorus had positive inhibition efficiencies on SRB-induced corrosion of X70 pipeline steel. Moreover, corrosion rate of X70 pipeline steel was declined from 19.17 to 3.75 mg·dm-2·day-1 by the presence of B. bacteriovorus.

This is the first report about using B. bacteriovorus to inhibit the corrosion induced by SRB. Compared to other anti-corrosion methods, the microbial inhibition methods exhibit more considerable application value due to its low cost, high efficiency and non-pollution.

The purpose of this study is to explore the influence of the sulfate reducing bacteria (SRB) on the corrosion of cupronickel.

Tests monitoring the change in free corrosion potential, linear polarization resistance and electrochemical impedance spectroscopy and examination using the scanning electron microscope and energy spectrum analysis were used to investigate the corrosion behavior of cupronickel in blank medium and in media inoculated with SRB to explore the influence of the SRB on the corrosion behavior of cupronickel alloy.

The results show that SRB can destroy the surface oxide film of cupronickel and significantly reduce the free corrosion potential and polarization resistance of the cupronickel, causing the cupronickel to corrode significantly.

SRB are widely found in the water supply system and is one of the important factors inducing microbial corrosion. This paper verified that SRB promote cupronickel corrosion and explored the influence and mechanism of attack.

Corrosion-producing microorganisms have different physiology and include sulfate-reducing bacteria, iron oxidizers and magnesium oxidizers. Biocorrosion has been seen in various industries, especially the petrochemicals and oil industries. One proposal to solve this problem is the use of bacteriophages to treat the bacteria-caused corrosion. The aims of this study were isolation and identification of corrosion-producing bacteria from petroleum pipeline corrosion as well as finding their specific bacteriophages for phage therapy purposes.

The sample pipes with the corrosion were obtained from the Gandomkar petroleum pipeline station, Chaharmahal and Bakhtiari, Iran. For screening the corrosion-producing bacteria, the rusted pipe samples were cultured in a selective culture medium, manganese agar. The purified individual colonies were subjected to molecular examinations. For isolating bacteriophages from silversmithing workshops wastewater in Isfahan, whole plate titration methods and transmission electron microscopy were used to isolate and detect phages.

The cultivation of corrosion-based material on manganese agar after 18 hours incubation at 30°C resulted in the isolation of cream-colored colonies. The microscopic examinations showed Gram-negative coccobacilli. Based on molecular examinations, the isolated bacteria were identified as Stenotrophomonas maltophilia strain PBM-IAUF-2 with Genebank accession number of KU145278.1. The found bacteriophage was related to the Siphoviridae family of phages.

This paper is the first report of isolation and identification of corrosion-producing bacteria and its specific lytic phages from Gandomkar petroleum pipeline station, Chaharmahal and Bakhtiari, Iran. The biological procedures for preventing the microbial corrosion could be an asset and considered as a potential in the petroleum and industrial microbiology. Phage therapy is considered as one of the economical methods for reducing the biocorrosion.