Storage Tank Design BGBataller December 14, 2010 2nd Semester, AY 2010-2011 Seminar Room, ChE Dept, CEAT-UPLB

Storage Tank CLASSIFICATION Shop-fabricated  Vcap≤23,700 gal Field erected  Vcap> 23,700 gal

Shop-Fabricated Tanks

Field Erected Tanks

Guidelines on Allowances 1. Vessels below 500 gallons (1.9 m3) are never more than 85% filled 2. Vessels above 500 gal (1.9 m3) are never more than 90% filled 3. Liquid in quantities less than 1,000 gal (3.8 m3) is stored in vertical tanks mounted on legs

Guidelines on Allowances 4. Liquid in quantities between 1,000 and 10,000 gal (3.8 and 38 m3) is stored in horizontal tanks mounted on a concrete foundation 5. Liquid in quantities exceeding 10,000 gal (3.8 m3) is stored in vertical tanks mounted on a concrete foundation.

SHELL DESIGN Shell Thickness (One – Foot Method) >> Applicable only for the Lower Course Shell Thickness

SHELL DESIGN Shell Thickness (One – Foot Method) >> Applicable only for the Upper Course Shell Thickness

SHELL DESIGN Shell Thickness (Variable Point Method) LOWER COURSE THICKNESS

SHELL DESIGN Shell Thickness (Variable Point Method) UPPER COURSE THICKNESS

Shell Design >> Variable Point Where:

Shell Design >> Variable Point Where x is a variable design point that is a function of: a. Thickness of layers b. Tank Radius c. Liquid Height >> is the minimum value among x1, x2, x3

Roof Thickness For Self-Supporting Roofs (FS=4)

Height between Stiffeners For Long Cylindrical Shell (E=30x106, FS=1.5, Poisson’s ratio = 0.3)

Bottom (annular) Plate Length For FS=2 and tb=0.25 to 0.75 in.