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The old adage “an ounce of prevention is worth a pound of cure” applies particularly well to practice of corrosion control in oil and gas pipelines and other heavy industry equipment. In most, but certainly not all, cases, corrosion is preventable. However, many industries still focus on outdated methods for corrosion mitigation, chasing corrosion rather than preventing it in the first place, perhaps in the erroneous belief that prevention methods are costly or difficult.
Research and development in the field of corrosion engineering has led to the creation and implementation of effective new technologies focused on strategic prevention of corrosion, and form the main component of cutting-edge corrosion control operations. A new category of corrosion control products: decontamination surfactants, function both separately and as the core of high-performing corrosion prevention systems that outperform standard corrosion mitigation efforts in terms of cost- and labor-savings, and significantly simplify and speed surface preparation and coating processes.
“Cure” vs. Prevention: The Difference
The “cure” is a passive approach that entails waiting for corrosion to appear, using frequent inspections in an attempt to mitigate corrosion damage (not corrosion as a phenomenon), followed by removal of the visible evidence of corrosion by blasting to a merely visual standard of hygiene, then coating metal surfaces with paint or coatings.
The “cure” in this case is analogous to wiping the blood and pus out of a wound, then covering it with a bandage. Without disinfection, the wound is likely to fester painfully. Likewise, failure to remove all existing soluble salts and non-soluble microcontaminants results in inevitable underfilm corrosion that eventually compromises protective coatings, leaving metal surfaces exposed and vulnerable to external corrosion factors.
Prevention is dynamic approach that entails adopting measures that removing the highest number of factors that cause corrosion from the equation, not simply palliating the problem once it begins. The systematic elimination of known root causes (known corrosion triggers that initiate corrosion reactions) both inside and outside metal surfaces is key to prevention. In the case of corrosion, especially in aggressive industrial environments such as oil, gas, marine and energy sectors, this means taking steps to a) eradicate corrosion triggers existing in metal surfaces in and b) protect metal surfaces from contact with corrosion triggers existing in the environment.
The core of this dynamic approach relies heavily on a new, biodegradable decontamination surfactant technology that complements existing surface preparation procedures. Decontamination is inserted into processes after wet or dry blasting, or simultaneously during wet abrasive vapor blasting to obtain “beyond visual” levels of metal hygiene that routinely exceed the highest NACE/SSPC.
The development of this unique product, known as CleanWirx, was the catalyst behind the Corrosion Prevention
Biodegradable, eco-friendly decontamination surfactant is sprayed onto the surface using the same WAVB equipment or a conventional spray system and allowed to dwell for 30 minutes or more to solubilize, react and disperse strongly bonded soluble salts, non-soluble sulfides and microcontaminants, simultaneously producing surfaces reflecting extremely high levels of metal hygiene with zero ionic contaminants detected (as determined by sensitive potassium ferricyanide testing). A stabilizing rinse agent removes the detritus left after decontamination and stabilizes metal.
The decontaminated surface naturally “hold the blast” longer to allow the tasks to flow in a single, continuous process from blast to decontamination to coating with no repetition or interruption of workflow, thus cutting time to project completion by roughly 40%. allowing consistent “first time, every time” inspection success.
This reliability translates into fewer delays, reduced downtime, tighter scheduling with less vulnerability to humidity and weather incidents, and lower risk of demurrage, without resorting to measures such as dehumidification or application of film-forming inhibitors. The resulting optimally receptive metal surfaces promote consistent coating adhesion and performance uncompromised by underfilm corrosion.
Conventional surface preparation involves dry or wet blasting that uses dangerous high PSI equipment and large amounts of media and/or water to clean surfaces of old coatings, mill scale, oil, film, dirt and/or visible rust. High PSI blasting can embed or drive corrosion causing moisture, water-dissolved salts, and potentially contaminated media deep into the pores of metal surfaces. In addition, high PSI necessarily damages structural integrity of substrates. Although on steel, the damage each time is generally minimal, the cumulative effect of multiple blasts should be noted. Shrouding of work area, cleanup and extensive respiratory PPE is required to prevent damage to worker and environment. Repeated blasting tasks waste energy. Process is sensitive to humidity, necessitating the use of dehumidifiers or inhibitors to “hold the blast” in attempt to maintain NAVE/SSPC inspected standards for visible levels of metal cleanliness required before coating. Sensitivity to humidity causes frequent delays and extend downtime (with associated demurrage) and often necessitates repeated process attempts. Highly contaminated surfaces are known to fail inspection repeatedly, requiring multiple attempts to meet inspection parameters for visual cleanliness only. Inhibitors and pickling agents often toxic to the environment require special attention. At no time does conventional surface preparation address the presence of microcontaminants in metal surfaces.
Advanced surface preparation involves wet abrasive vapor blasting (WAVB) that uses safer, low PSI equipment and a small fraction of the media and water used by dry or wet blasting to clean surfaces of old coatings, mill scale, oil, film, dirt and/or visible rust. WAVB can be used on delicate surfaces without damaging the surface. The force of impact of higher-mass moist media bursts on impact, removing impurities from the metal surface without driving them deeper into pores by excessive force. Dust particles created are encapsulated in water and fall to the workfloor, greatly alleviating danger to respiratory health and the need for extensive shrouding of the work area to protect from environmental impact. Biodegradable, eco-friendly decontamination surfactant is sprayed onto the surface using the same WAVB equipment or a conventional spray system and allowed to dwell for 30 minutes or more to solubilize, react and disperse strongly bonded soluble salts, non-soluble sulfides and microcontaminants, simultaneously producing surfaces reflecting extremely high levels of metal hygiene with zero ionic contaminants detected (as determined by sensitive potassium ferricyanide testing). A stabilizing rinse agent removes the detritus left after decontamination and stabilizes metal. The result is an optimally receptive surface proven to promote maximum coating/lining adhesion and performance. Advanced surface preparation hygiene results exceed the highest SSPC/NACE and industry standard. These advanced surface preparation processes are far less sensitive to humidity, thus use of dehumidifiers and inhibitors are not necessary. The decontaminated surface naturally “hold the blast” longer to allow the tasks to flow in a single, continuous process from blast to decontamination to coating with no repetition or interruption of workflow, thus cutting time to project completion by roughly 40%. Surfaces pass inspection the first time. This reliability translates into fewer delays, reduced downtime, tighter scheduling, and lower risk of demurrage.