Microbial-induced corrosion (MIC) is a type of corrosion that occurs as a result of the activity of microorganisms. MIC can cause significant damage to metal structures, including pipelines, storage tanks, and ships. MIC testing is essential for understanding and preventing this type of corrosion. While MIC testing has been around since the 20th century, new technologies are making it easier for pipeline engineers to determine the difference between MIC and other types of corrosion.
What is Microbial-Induced Corrosion (MIC)?
MIC is a type of corrosion that occurs as a result of the activity of microorganisms, including bacteria, fungi, and algae. These microorganisms produce metabolic byproducts that can be corrosive to metal surfaces. In addition, microorganisms can form biofilms on metal surfaces, which can accelerate the corrosion process.
MIC is a significant problem in various industries, including oil and gas, marine, and water treatment. MIC can cause leaks, failures, and other safety hazards, leading to costly repairs and downtime.
MIC Testing Methods
There are several methods for MIC testing, including coupon tests, biocide tests, and microbial analysis.
Coupon tests involve exposing metal coupons to microorganisms and measuring the corrosion rate. The coupons are placed in a solution containing microorganisms, and the corrosion rate is measured over time. This method can help determine the susceptibility of a metal to MIC.
Biocide tests involve adding biocides to the microorganism solution to determine their effectiveness in controlling MIC. Biocides are chemicals that can kill or inhibit the growth of microorganisms. This method can help identify the most effective biocide for a specific application.
Microbial analysis involves identifying the type and number of microorganisms present in a sample. This method can help determine the microbial community’s composition and activity, providing insight into the potential for MIC.
Preventing MIC
Preventing MIC involves several approaches, including maintaining a clean and dry environment, controlling the pH and temperature, and using corrosion inhibitors and biocides.
Maintaining a clean and dry environment can prevent the buildup of biofilms and other corrosive substances. Controlling the pH and temperature can also reduce the growth and activity of microorganisms.
Corrosion inhibitors and biocides can be added to the metal surfaces or the surrounding environment to prevent MIC. Corrosion inhibitors work by forming a protective layer on the metal surface, preventing corrosive substances from reaching the metal. Biocides can kill or inhibit the growth of microorganisms.
Conclusion
MIC testing is essential for understanding and preventing microbial-induced corrosion. Methods such as coupon tests, biocide tests, and microbial analysis can help identify the susceptibility of a metal to MIC and the effectiveness of prevention measures. Investing in MIC testing is worth it. By implementing effective prevention measures, we can reduce the risk of MIC and ensure the safety and reliability of metal structures in various industries.