Storage tanks maximum thickness

The maximum strain in a vertical liquid storage tank is given by e = pgHR/lEh where H is the level above the base of the liquid of density p, and h is the wall thickness of the tank. 

A storage tank for concentrated nitric acid will be constructed from aluminium to resist corrosion. The tank is to have an inside diameter of 6 m and a height of 17 m. The maximum liquid level in the tank will be at 16 m. Estimate the plate thickness required at the base of the tank. Take the allowable design stress for aluminium as 90 N/mm2. 

Raising the maximum storage tank level within the safe operating envelope for that tank. Replacement of a vessel or piping with equipment of the same size, metallurgy, wall thickness, pressure rating, and design temperature. 

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