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Protecting concrete in wastewater treatment plant from corrosion

I am a wastewater treatment plant superintendent in a small town with a population below 5000. We have been having problems with concrete being attacked by sewer gases (H₂S). We have a very limited maintenance budget and we would like to do the maintenance ourselves. We have done some checking and most of the products recommended were linings and epoxy coatings or a multilayered combinations thereof. These require a lot of surface preparation, specialized equipment and contractors and are expensive for us to use. Does anyone know of a product that is easy to use, does not require much surface preparation and preferably environmentally friendly that we can apply ourselves? Any recommendations or ideas will be appreciated.

Brandon Elliott
USA
1999

As a very inexpensive coating, I've used a tar like black epoxy. It has good acid resistance for a paint - H₂S? - I don't know. However, I would buy just a small amount and paint a test patch - you can apply these products around 8 mils thick per coat. No matter what you choose to use, you'll have to clean the existing concrete well prior to application if you expect to get good results. This may involve grit blasting the floor prior to application. This is just a "poor man's" fix - it might get you by but it will never be as good as an engineered floor coating - good luck.

Mark McGlynn
- Oklahoma City, Oklahoma
1999

Try a drop-in liner, they are made of PVC in almost any size.

Guillermo Luna
- Mexico City, Mexico
1999

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We had a similar problem with one of our wastewater treatment facilities. We have tried a water based , environmentally safe product that can be applied like paint and needs little surface preparation. In addition it is flexible and can bridge any existing concrete cracks. Although we were skeptical initially, the manufacturer showed us a testimonial on a one year test result in an actual treatment plant which convinced us to use the product. In addition the product came with a warranty which practically made it risk free. We have had it for almost 1 year with no problems.

I hope this helps.

Emmett W. Haddox
- Topeka, Kansas
2000

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Ed. note: Sorry, folks, but we had to purge brand names and limit this discussion to generic, technical answers, rather than a discussion of proprietary products.