2 replies to this topic

[ceyer]

ı xant to make a styrene production design for school.what is the residence time for ethylbenzene for storage of intermediate tank.and what is the volume of a standard vertical storage tank

[Doggert]

Residence time for storage? Do you meant "shelf-life"? The residence time for storage is something that is typically set by the accountants, logisitics personnel, and managers - as it has more to do with inventory control than the actual process.

Or maybe I'm misunderstanding your problem. Please explain in greater detail what you need.

Also, there is no real standard for volume of vertical storage tanks. You really just need to use common sense. The first thing you need to know is how much of the material you need to store. Now you have your volueme.

From that point, determine an appropriate height x diameter (assuming you're going to use a cylindrical tank). Be sure to be realistic when you choose these numbers - for instance, you don't want a tank which is 10 cm in diameter by 1 kilomter in height. Likewise, you don't want a tank that is 5 cm in height and 1 kilomter in diameter. Determine a good "normal" size for a tank. If your size ends up being too large, then consider splitting the volume between two or more tanks.

That's about all I can tell you at this point, given the detail you've presented. I have been involved in process engineering for a styrenics plant in my past for about 3 years, so I may be able to help with further questions once you have more detail.

[pleckner]

We try to design vessels with a length to diameter ratio of 1:1 or 2:1. In the "old" days, sheets were cut in 8' sections so we would try to make the heights multiples of 8' or 4' to minimize waste (that you end up paying for). Today, they cut just about anything. Just remember that you get more volume for your money on the diameter side than you do on the vertical side but I would still try to maintain the 1:1 or 2:1 ratios. You also need to decide if it will be a horizontal vessel or a vertical vessel. If vertical, will it be with a flat bottom mounted on a pad or will it have dished type heads and be on legs.

Do a Google on storage tanks and see what the world has to offer.