Interior Coating for Surge Tank

"installing a new bottom, an interior coating as well as painting the exterior of the tank"

So, it's an existing tank?

What's it made of?

Is the inside painted now?

What's the total thermal range the tank will see?

So, it's an existing tank?

yes

What's it made of?

carbon steel plate SA-285 gr c

Is the inside painted now?

No just rusty and corroded

What's the total thermal range the tank will see?

The tank will run between 120 and 140 degrees F

3 times a week our dimin. water system re gens and dumps 2-4% HCL/water into the effluent system. This causes the high acidic excursions. I am currently getting a coatings engineer to design a coating and give an installation price on the interior coating. We are looking at epoxy type coatings at present. I am sure everything will be blasted to a white metal profile before coating can occur. I only have 20 days to do this entire job and I have to start in 2 weeks so there is an urgency to figure it out and get started.

pH 2 is extremely acidic. Is it HF? If it's not, you can use FRP lining. If it is, PP or epoxy would be better.

Have you looked at RAVEN coatings/linings?

Will it see any organics? Organic solvents in the ppm range can be significant for some materials, even when low pH is not a problem.

How durable will it need to be? I don't care how chemically resistant a thin film lining is if it's going to get dinged up.

Your long life/low cost requirements are often at odds with one another on linings, so hopefully you get good unbiased advice from your coatings engineer. You should strongly consider independant 3rd party inspection by a NACE certified inspector during the lining process.

Epoxy would seem likely to be your best bet on all criteria.

Check if organics are likely to be present and what they will be then have your coating supplier advise.

Good luck

From all the information I have received so far the epoxy seems to be the best bet and is what I am currently getting pricing on. As far as durability goes it is always a concern in a paper mill although in this particular tank it really should not be a problem. As soon as I say that I will probably catch a maintenance guy setting a bobcat over into the tank to clean it or something like that. Thanks all for your suggestions, I am currently looking through the options.

Oh, you didn't say paper mill before - poor lining is doomed

As a former materials engineering consultant, I could tell you some pretty "interesting" paper mill stories.

One follow up question that comes to mind based upon your comment that it's a paper mill application - will the lining see caustic now and again (e.g. might be used to neutralize the low pH excursions you mentioned)?

Yes It could see caustic when we would do a caustic boil out on the Paper machine head box but not very often and then it would not be enough to change the Ph significantly. The current through put of our effluent system is somewhere around 14-17 million gallons per day so compared to this a few hundred gallons of caustic wouldn't be a big difference. I went back and checked with the environmental guys and they said that the acid is the problem that I should plan for. I will be doing the pre bid walk through tomorrow for the new steel portion of the bottom and should have suggestions for a coating as well as budgetary number then as well. I have 4 companies in mind for quoting the coating and application portion of this work but I need to be able to make sure all the coatings are in the same ball park so to speak in that they will do what I need.

Like I said earlier, we use Raven 405 inside sewer manholes and to line the walls of our pump stations, and it holds up better than anything. We have tried 5 or 6 other linings, but Raven has always outlasted them. Our main reason for lining manholes is to protect the concrete against the leaching caused by the gases that build up.

Hello and thanks for the information. I am looking into the Raven lining system. Are you aware of anywhere this coating has been applied to steel tanks? A few years ago I did a no dig rehabilitation project of the underground pipe line that feeds this surge tank and I used a vinyl easter resin "Invertapipe" brand/type liner system and it worked very well. I assume this is one application of the Raven coating or is it more of a sprayed on type coating?

The raven is a sprayed on system.

Please contact me with any questions regarding Raven products. I'm a Sales Rep for RLS Solutions that manufacturers Raven epoxies. 800-324-2810 or cell: 216-212-6493. Email: duggerj@rlssolutions.com.

I look forward to hearing from you.

Best Regards,

James Dugger