Corrosion Controls Research Articles

Corrosion-enabled tryptophan biosensing enhancement on commercially available Mg alloy surfaces.

A novel method enhances tryptophan fluorescence signals 5.45 times using a corrosion-modified magnesium alloy. Corrosion controls and stabilizes the surface morphology, resulting in a significant fluorescence enhancement. This highlights its biosensing potential with long-term stability, crucial for understanding the impact of tryptophan on metabolic and neurological disorders.

Unveiling nano-scaled chemical inhomogeneity impacts on corrosion of Ce-modified 2507 super-duplex stainless steels

The widely used stainless steels and their deformed variants are anticorrosive in ambient conditions due to passivation layers composed of chromium oxides. Conventionally, corrosion and erosion of the steels are attributed to the breakdown of such layers but seldomly to the origin that depends on surface heterogeneity at the microscopic level. In this work, the nanometer-scaled chemical heterogeneity at the surface unveiled via spectro-microscopy and chemometric analysis unexpectedly dominates the breakdown and corrosion behavior of the cold-rolled Ce-modified 2507 super-duplex stainless steels (SDSS) over its hot-deformed counterpart. Though relatively uniformly covered by a native Cr2O3 layer revealed by X-ray photoemission electron microscopy, the cold-rolled SDSS behaved poorly in passivity because of locally distributed Fe3+ rich nano-islands over the Fe/Cr oxide layer. This atomic-level knowledge provides a deep understanding of corrosion of stainless steel and is expected to benefit corrosion controls of similar high-alloyed metals.

Electro-Chemical Deposited Cu-Ni Binary and Cu-Ni-Mn Ternary Alloys from Sulphate Bath for Anti-Corrosive Coating Applications in Brine Environment: Effect of Corrosion Behaviour, Polarization Studies, Morphological and Structural Characterizations

Electrochemical preparation of binary alloy of Cu-Ni from acid sulphate bath containing citric acid using Potentiostatic method. The effects of alloy composition were monitored. Copper is widely used in industry, because of its good thermal conductivity and mechanical characteristics. The accumulation of Nickel & Manganese to Copper enhances itspotency, vigour, toughness, endurance, permanence&also the corrosion-resistanceas well asattrition. Corrosion controls of metal have technical environmental and economical importance. The Cu-Ni-Mn alloyswere used commercially for decorative and protective purpose and also in marine applications. The thin film coating characterized by SEM, EDAX and XRD shows morphological, compositional and structural properties of alloys respectively.

Acceleration of steel corrosion in concrete by cyclic wetting and drying: effect of drying duration and concrete quality

To investigate the influence of concrete quality and drying duration on steel corrosion rate when cyclic wetting and drying is used to accelerate corrosion propagation. To inform future similar experimental work in the area of accelerated steel corrosion in concrete. Concrete prisms (100 × 100 × 240 mm) were made using two w/b ratios (0.40 and 0.65) and three binder types. After elimination of the corrosion initiation phase using an impressed current technique, the specimens were exposed to cycles of wetting (2 days) and drying (1, 3, 5, or 7 days). Steel corrosion rate was monitored using a coulostatic technique, over a period of ca. 170 days. Both the duration of drying and concrete quality profoundly affect corrosion rate of steel in concrete in a cyclic wetting and drying regime. A general inference from the results is that with drying, the denser microstructure concretes with high resistivity exhibited resistivity corrosion control while the less dense microstructure concretes with low resistivity exhibited both cathodic and resistivity corrosion controls. In accelerated corrosion testing using cyclic wetting and drying, the combined effects of concrete quality and drying duration need to be considered in determining corrosion rate.

A Review of Field Corrosion Control and Monitoring Techniques of the Upstream Oil and Gas Pipelines

All steel pipelines used in hydrocarbon transportation are susceptible to either electrolytic or galvanic corrosion attack which deteriorate with time leading to failure even before end of design life. Consequences of corrosion attack and eventual failure of pipelines within oil and gas industry has been classified into economic, health, safety and environmental impacts. The present study considers detailed review of practical field corrosion control and monitoring mechanisms necessary to preserve, extend service life of pipelines and reduce corrosion impacts. The corrosion controls are various preventive strategies considered during construction and prior to pipelines’ commissioning which include design, material selection, protective coating, chemical treatment and cathodic protection system. But the corrosion monitoring strategy is aimed at establishing condition of pipelines and environmental variables that may accelerate corrosion process and this includes potential survey, bacteria count, corrosion coupons and intelligent pigging. The identified corrosion control and monitoring techniques are not governed by any industry code and standard but has been generally accepted as best practice within the oil and gas industry as ways of combating corrosion and evaluating pipelines condition. Therefore, effective implementation of the identified corrosion control and monitoring strategies would limit corrosion attack and guide pipelines’ operators to make informed decision and timely respond to corrosion threat before failures. Keywords : cathodic protection, corrosion mechanism, control and monitoring, pipelines, oil and gas.

Comparing the 2014–2016 Flint Water Crisis to the 1993 Milwaukee Cryptosporidium Outbreak

Contrasting the 1993 Cryptosporidium parvum outbreak in Milwaukee to the 2014–2016 Flint Water Crisis through an environmental justice perspective examines how the cities’ population demographics influenced the local, state, and national governmental responses and outcomes. In October 2014, the Flint Emergency Manager switched from Detroit's water system to the Flint River. Without corrosion controls applied, Legionnaires’ disease cases increased, and childhood lead poisoning levels spiked twofold in Flint. In Milwaukee, the cryptosporidium outbreak impacted the five-county area serviced by Milwaukee Water Works. City officials shut down the contaminated treatment facility and began preventative measures. While the city of Milwaukee boosts a high minority population and low median income, Milwaukee's surrounding areas are predominantly white, and the median income is nearly double of the city. The socioeconomic makeup in the City of Flint triggered the government's denial of problems with the Flint River's water and the lack of response, thus demonstrating that the Flint Water Crisis is an example of environmental injustice. In many ways, Milwaukee's income and demographics parallel Flint. However, the distribution of cryptosporidium, where mainly white individuals became ill, influenced the recognition and long-term solutions applied. Comparing the origins of the crises and costs concludes that the populations shaped political responses. Thus, situational environmental injustice explains differential outcomes. The localized governmental response in Milwaukee and impacted population effectively ended the cryptosporidium outbreak. However, the state control in Michigan and inadequate coordination with other agencies have prolonged the Flint Water Crisis. Finally, long-term policies are suggested for Flint.

Inhibitive properties of 2,5-bis(n-methylphenyl)-1,3,4-oxadiazole and biocide on corrosion, biocorrosion and scaling controls of brass in simulated cooling water

2,5-Bis(n-methylphenyl)-1,3,4-oxadiazole with (n=2,3,4), denoted n-MPOX, have been investigated by using potentiodynamic polarization (PP) and electrochemical impedance spectroscopy (EIS) methods, to evaluate the electrochemical behavior of brass in simulated cooling water system. The PP study revealed that oxadiazole inhibited both cathodic and anodic reactions, indicating a mixed type control of inhibition. It was shown that, 3-MPOX as well as 4-MPOX, were the best inhibitors and the inhibition efficiency followed the sequence: 3-MPOX⩾4-MPOX≫2-MPOX. The interference between non-oxidizing biocide CTAB and 3-MPOX and 4-MPOX against corrosion and biocorrosion has also been studied.

Monitoring of anaerobic microbially influenced corrosion via electrochemical frequency modulation

Electrochemical frequency modulation (EFM) is a rather novel technique to monitor corrosion rates in situ, providing direct access to Tafel slopes with only minor polarization. So far EFM has been applied mainly for electrochemical corrosion monitoring in purely chemical corrosion systems with predominant uniform corrosion, but it has also great potential for monitoring microbially influenced corrosion (MIC). Thus, in this study MIC induced by different cultures of sulfate-reducing bacteria (SRB) was monitored with EFM, and compared to results from linear polarization resistance (LPR) and measurements of the free corrosion potential Ecorr. The electrochemical results obtained in small scale bioreactors with a three electrode setup were complemented by chemical analysis and SEM observations. SRB featuring high corrosion rates were compared to non-corrosive but still H2-consuming control SRB, sterile controls and abiotic sulfide corrosion controls. Corrosion rates determined with EFM and LPR were accurate and precise in all cases as long as the system was based on uniform corrosion. However with the onset of localized corrosion both methods fail to predict accurate rates. Unlike other electrochemical corrosion rate measurements, EFM has the advantage to provide indicating ratios in the current response at different frequencies, so-called causality factors, which allow identifying changes in the corrosion system and therefore assessing the accurateness of the obtained results. As a consequence EFM is a promising electrochemical corrosion monitoring technique for MIC in fundamental and applied studies.

English

Metal corrosion is an electrochemical reaction between the environment and a metal, in which microbes are thought to play a very important role. The rates at which various types of metals corrode are dependent upon environmental conditions as well as on the type of metals. The most well studied bacteria involved in biocorrosion are the anaerobic sulphate reducing bacteria (SRB) and other bacteria such as methanogens, acid producers as well as the aerobic iron respirers and manganese oxidisers. The biofilm produced by the microorganisms facilitates bicorrosion by altering the chemistry such as pH, pressure, oxygen levels and nutrients at the interface between the metal and the bulk solution. Therefore biofilms can be used to alter the conditions at a metal surface, and to accelerate or inhibit corrosion. In this review, the proposed mechanisms of how bacteria contribute to the biocorrosion processes and the groups of bacteria involved will be included. Different strategies for biocorrosion control will also be discussed. Biological control strategies such as biocompetitve exclusion and the use of antimicrobial producing biofilm forming bacteria show increasing promise as more effective, environmental friendly and long term method of corrosion controls. Key words: Microbially influenced corrosion, biocorrosion control strategies, biofilms, microorganisms, biocompetitive exclusion

Biocorrosion control: Current strategies and promising alternatives

Metal corrosion is an electrochemical reaction between the environment and a metal, in which microbes are thought to play a very important role. The rates at which various types of metals corrode are dependent upon environmental conditions as well as on the type of metals. The most well studied bacteria involved in biocorrosion are the anaerobic sulphate reducing bacteria (SRB) and other bacteria such as methanogens, acid producers as well as the aerobic iron respirers and manganese oxidisers. The biofilm produced by the microorganisms facilitates bicorrosion by altering the chemistry such as pH, pressure, oxygen levels and nutrients at the interface between the metal and the bulk solution. Therefore biofilms can be used to alter the conditions at a metal surface, and to accelerate or inhibit corrosion. In this review, the proposed mechanisms of how bacteria contribute to the biocorrosion processes and the groups of bacteria involved will be included. Different strategies for biocorrosion control will also be discussed. Biological control strategies such as biocompetitve exclusion and the use of antimicrobial producing biofilm forming bacteria show increasing promise as more effective, environmental friendly and long term method of corrosion controls. Key words: Microbially influenced corrosion, biocorrosion control strategies, biofilms, microorganisms, biocompetitive exclusion.

Assessing the impact of corrosion control measures on tap drinking water of the Greater Vancouver Regional District

A study on the quality of water distributed within the Greater Vancouver Regional District (GVRD) was carried out to evaluate the effectiveness of previously implemented corrosion controls. In addition, the effect of temperature fluctuations was investigated to determine if it influenced the efficacy of the control measures. The GVRD was divided into four distribution areas. The Capilano water had no corrosion control treatment. Seymour, Coquitlam, and Newton waters were treated with soda ash, resulting in a pH of 6.8, 6.9, and 8.1, respectively. Standing cold water and running hot and cold water samples were collected from the four zones and analyzed for lead, copper, and zinc concentrations. The source water did not influence the amount of lead at the tap. The source water did influence the amount of copper and zinc at the tap. The highest copper and zinc concentrations were found in the water with the lowest pH (Capilano) and the lowest concentrations in the water with the highest pH (Newton). Seasonal temperature fluctuations of distributed GVRD water did not affect the metal concentrations in the water.Key words: corrosion control, GVRD drinking water, copper, lead, zinc, pH adjustment.

Chlorination Systems—Feeding Chlorine Into Water

The most common type of chlorination system used in water treatment plants is the solution‐feed vacuum‐type chlorination system. This article describes the solution‐ feed vacuum‐type chlorination system's regulator, rate valve, and ejector. Accompanying this article is a list of guidelines for inspecting and maintaining these components. Also discussed are guidelines for the handling of chlorine containers, connecting chlorine containers, temperature and corrosion controls, and leakage checks.

A Positive Approach to Corrosion Control of Submersible Vault Type Urd Systems

This presentation establishes corrosion controls for submersible vault type electric systems and includes a computerized analysis of galvanic and electrolytic conditions. Separate tests of anode configuration and of cathodic protection interference with the copper concentric neutral of a direct buried cable are discussed.