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ATM tank design-Corrosives
- Thread starter llls
- Start date
Where are you located?
And what is the product?
In the US, the tank would typically be specified with references to API-650 or API-620 "as applicable". Neither standard specifically covers leg-supported tanks. Neither addresses the specific requirements for corrosion with various products.
AWWA D100 covers leg supported tanks, that is, water towers. But it covers the design of legs and accompanying stresses in the shell in a very vague fashion that is of no help in the design process.
We used to have a standard that dealt specifically with sulfuric acid tanks, but I don't recall who put it out. It addressed mainly corrosion issues, as I recall, not structural details.
And what is the product?
In the US, the tank would typically be specified with references to API-650 or API-620 "as applicable". Neither standard specifically covers leg-supported tanks. Neither addresses the specific requirements for corrosion with various products.
AWWA D100 covers leg supported tanks, that is, water towers. But it covers the design of legs and accompanying stresses in the shell in a very vague fashion that is of no help in the design process.
We used to have a standard that dealt specifically with sulfuric acid tanks, but I don't recall who put it out. It addressed mainly corrosion issues, as I recall, not structural details.
- Thread starter
- #3
You have several options. First, for a 3M diameter, you should forget about the legs and use a flat bottom tank. Legs are usually limited to 1M diameter tank. Then specify an API Standard 650 tank in stainless steel or carbon steel with an internal liner (Plasite etc). You can consider a fiberglass reinforced plastic tank per API Standard 12P. A flat bottom tank can be designed with secondary containment and completely draining.
hbw,
I think it is a drastic statement to say that legs are usually limited to 1m diameter tanks. I just finished a 4m diamter x 50 m tall tank on legs. It was an EN 13445 designed pressure vessel. Legs were needed for access and a skirt would not have had enough room to move around the equipment in the bottom. The legs were relatively tall, about 4m to 5m and x-braced.
lls,
You need to tell us more about the tank, height for example. Being in NZ, I expect you will have large seismic loads. I've done work at the Kinleith mill and seismic was a big issue.
I think it is a drastic statement to say that legs are usually limited to 1m diameter tanks. I just finished a 4m diamter x 50 m tall tank on legs. It was an EN 13445 designed pressure vessel. Legs were needed for access and a skirt would not have had enough room to move around the equipment in the bottom. The legs were relatively tall, about 4m to 5m and x-braced.
lls,
You need to tell us more about the tank, height for example. Being in NZ, I expect you will have large seismic loads. I've done work at the Kinleith mill and seismic was a big issue.
- Thread starter
- #7
Hi Guys, Sorry for not replying. OK the tank I am looking at needs a head room of 1.5m, we are planning to have a 15 deg cone bottom (mainly for self draining requirement). The shell T-T is about 6.5m. Earlier comments by hdw to limit legged tanks to 1m Dia, any idea how this limit came from, as I have sean many larger Dia tanks on leggs or Skirts type supports. I our case we cant use the skirt design due to operational requirement etc.
"Carbon Steel Sulfuric Acid Storage Tank- Inspection Guidelines" published by C-I-L Corporation of America (an acid producer/supplier), Stamford Connecticut, copyright 1986. Lots of useful information, specifically dealing with sulfuric acid. That's the design standard I mentioned in my post above.
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