α. Mentioned thread
http://www.cheresour...tanks-ld-ratio/ reveals following (among other data):
α1. S Mukherjee's Table reports dimensions of standard tanks. Max height is 25 m for every diameter larger than 15 m. Lower diameters have lower max height (reasonable).
α2. It seems that tanks higher than 15 m are not very common.
Note: Only once have we determined tank diameter and height considering standard sheet dimensions.
β. As tank height increases, plate thickness increases; besides requirements for foundations & earthquake protection get more sophisticated (so more expensive); and so do requirements for tank stiffness, to resist buckling (and bending moments) for high H/D ratios. A practical limit of height = 30 m could be considered, according to previous posts. Over here petroleum tanks of height = 23 m are not rear.
γ. A verified example from precipitators, used as crystallizers in alumina production, concerns atmospheric tanks, each of them of D=14 m, H=29.3 m, total weight ~220 ton (empty). They had to be high for following reasons ( increasing importance, last reason most important).
- there would be ~ 30 tanks in total, bigger diameter would mean more space.
- each tank had an agitator to keep particles in suspension (agitation is not efficient in big diameters)
- there was a platform at H=28 m (say) communicating with all tanks. Valves had to be manipulated (not in every shift) from the platform.
Plant layout was affected by the need of Precipitators' foundation to be on rock. Area was of high seismism, requiring special survey for the protective measures in an earthquake. Stored liquid oscillations during it (with risk of caustic liquid to pour out) imposed covered tanks, contrary to usual practice of open tanks.
So these are some special issues faced with high tanks.
Edited by kkala, 10 December 2011 - 10:43 PM.