5 Tips For The 100-Year Storage Tank
Treatment plant showrunners are constantly looking for ways to save. They investigate processes that can be automated and new pieces of equipment that can be brought in to conserve energy. But few realize that one of the simplest ways to save money in the long run concerns the ubiquitous behemoths surrounding the plant. They fail to properly maintain their storage tanks.
While it’s difficult to estimate the exact cost savings that result from taking care of your storage tanks, Lourdes Borrego-O’Brien, a manager with Tank Industry Consultants, has found that with proper maintenance, a storage tank can last up to 100 years. Maintaining the tank that’s already in place at nominal cost will mean avoiding an expensive full-scale replacement for decades.
“Take a proactive approach to tank maintenance,” implored Borrego-O’Brien, before offering these tips for proper tank management:
- Conduct routine weekly checks for cracks in the foundation, deterioration, and corrosion.
“Acknowledge that all types of tank construction — concrete, welded steel, or bolted steel — require maintenance,” said Borrego-O’Brien. “Inspect tanks on a regular schedule to identify deficiencies so that small problems don’t turn into big and expensive ones.”
- Arrange a full inspection and clean-out of your tank every three to five years.
This recommendation is per the American Water Works Association (AWWA) and endorsed by Borrego-O’Brien. In watersheds with particularly high sediments, annual clean-outs are recommended.
- Don’t skimp on the coating.
If a top-quality coat is applied to the tank the first time around, maintenance costs will be reduced for years to come. A good coating is the primary defense against corrosion. As metal loss is eliminated, so too are weld repair costs. Tank rafters and stiffeners will last much longer as well.
Plus, a good original coating means that when it is time for maintenance, there’s the opportunity to “topcoat” over the existing layer, instead of starting from scratch.
“The owner can significantly reduce repainting costs if the existing coating type, thickness, condition, and adhesion allow for topcoating of an existing coating system, which would cost approximately two-thirds or less of a full recoat,” said Borrego-O’Brien.
- And while we’re talking about coating, be sure to watch closely.
Borrego-O’Brien warns of a pitfall that is all too common in the world of storage tank maintenance: contractor negligence. Be sure to prepare highly-detailed and specific documents when outsourcing tank coating work and to solicit competitive bids from qualified contractors. But don’t rely solely on these methods to ensure the job is done right.
“The observation of the contractor’s workmanship is one of the most important parts of a tank rehabilitation project,” said Borrego-O’Brien. “The best written, most thorough specifications do not assure the contractor will complete the project correctly.”
Workers should be aware of atmospheric conditions as specific as humidity, dew point, air, and steel temperatures, all of which can affect a coat’s total lifespan at the point of application. The right contractor will suspend work whenever these conditions become unfavorable. Overseeing the details of a coating process might seem authoritarian, but leaving a contractor to do a shoddy job will have an all too real effect on the tank’s life.
“The ability of a coating system to achieve its anticipated service life is directly proportional to the quality of the workmanship during application,” said Borrego-O’Brien. “Therefore, money spent on project observation will be paid back in a longer-lasting coating system.”
- Keep up with new technology
It might not jump out as an industry ripe for innovation, but there are several emerging technologies that are exciting the world of storage tank maintenance. Borrego-O’Brien mentioned robotic blasting equipment, 100 percent solids coatings, improved impressed current cathodic protection systems, and improved active and passive mixing systems as trends to stay on top of.