Vertical tanks

Single Wall. Single-wall tanks are usually cylindrical and may have either vertical or horizontal orientation. Horizontal tanks are generally supported by two saddle supports and use more space than vertical tanks. Horizontal tanks have an advantage in that leaks can be seen as they occur. 

UL 58 covers horizontal steel tanks up to 190 m (50,000 gal), with a maximum diameter of 3.66 m (12 ft), and a maximum length of six diameters. Thickness and a number of design and fabrication details are given. UL 142 covers horizontal steel tanks up to 190 m (50,000 ffal) (like UL 58), and vertical tanks up to 10.7-m (35-ft) height. Tmckness and other details are given. The maximum diameter for a vertical tank is not specified. 

The Underwriters Standards overlap API, but include tanks that are too small for API Standards. Undei writers Standards are, however, not as detailed as API and therefore put more responsibility on the designer. They do not specify grades of steel other than requiring weldability. Designers should also place their own limits on the diameter (or thickness) of vertical tanks. They can obtain guidance from API. 

Equivalent-Area Concept The preceding equations for batch operations, particularly Eq. 11-35 can be appliedforthe calculation of heat loss from tanks which are allowed to cool over an extended period of time. However, different surfaces of a tank, snch as the top (which would not be in contact with the tank contents) and the bottom, may have coefficients of heat transfer which are different from those of the vertical tank walls. The simplest way to resolve this difficulty is to nse an equivalent area A in the appropriate equations where... 

Physical depth or height of turbine mixer, ft or in., consistent with other dimensions. Figure 5-34 = Impeller blade wndtii, ft = width of baffles in vertical tank. Figure 5-34. 

The wetted area of the tank or storage vessel shall be calculated as follows For spheres and spheroids, the wetted area is equal to 55 percent of the total surface area or the surface area to a height of 30 feet (9.14 meters), whichever is greater. For horizontal tanks, the wetted area is equal to 75 percent of the total surface area For vertical tanks, the wetted area is equal to the total surface area of the shell within a maximum height of 30 feet (9,14 meters) above grade. 

For venl area limited or restricted to one end of an elongated enclosure (vertical tank, silo, etc.), the venting equation is limited to ... 

The filling pipe should enter at the top of most horizontal storage tanks. For vertical tanks up to 3 meters (10 ft) diameter the filling pipe should be fitted at the top and then bend through 180°. This directs the incoming oil fuel down one side of the tank and minimizes air entrainment. 

With storage tanks which are filled from the bottom such as large vertical tanks, the stirring action of incoming oil will carry any water (which would normally settle out) into the oil-handling system. In these circumstances, any daily service tank used in the system should receive regular inspection to ensure that water has not accumulated. Any oil/water mixtures should be drained into suitable containers and subsequently removed for disposal into a separator or interceptor. 

Vertical tanks over 3.65 meters (12 ft) high should have a further manhole fitted near the bottom to provide access for cleaning and maintenance of any storageheating facilities. 

Pressure filters are available in either horizontal or vertical tank (vessel) arrangements, with manual or automatic backwashing facilities and with tanks constructed of steel or noncorrosive construction materials. Flow through the filters is normally from the top and then down through the bed. 

The design of fixed roof, vertical tanks is discussed in Chapter 13, Section 13.16. 

Horizontal or vertical tanks are used, depending on the size and duty. Where only a small hold-up volume is required this can be provided by extending the column base, or, for reflux accumulators, by extending the bottom header of the condenser. 

Figure 145. Model of the Cylindrical vertical tank used in experiments...

Liquid in quantities less than 1,000 gal (3.8 m3) is stored in vertical tanks mounted on legs.9... 

One rule of thumb is to make the floor-to-floor heights 8-10 ft (approximately 3m) higher than the sides of a dished-head vertical tank.6... 

When V6 in cylinders are conveyed, a simple vertical tank will be used instead of a cyclone for separating the solids from the air. It is assumed a 4 fit 8 ft aluminum vessel will suffice. 

A is the area absorbing heat (in ft2) for the following geometries for spheres, 55% of total exposed area for horizontal tanks, 75% of total exposed area for vertical tanks, 100% of total exposed area for first 30 ft, and Q is the total heat input to the vessel (in Btu/hr). 

The typical back-pulse filter is a vertical tank pressure vessel with a conical bottom,... 

Pressure leaf filters are supplied in a wide range of size and materials of construction. One typical design is the Verti-jet unit with a vertical tank and vertical leaf filter, as shown in Figure 7.12, with rectangular leaves mounted individually but connected to a common outlet manifold. For sluice cleaning either a stationary or oscillating jet system... 

Use of subsurface foam delivery systems for fixed roof vertical tanks is an option but there are limitations, refer to Section 7.4.10, Foam Systems. 

ULC S630, Shop Fabricated Steel Aboveground Vertical Tanks for Flammable and Combustible Liquids, covers single-and double-wall cylindrical vertical steel nonpressure tanks. 

Assume a boiler built of V inch BWG 14 tubes, 4.9 m long. The heat is supplied by saturated steam at 381.7 K. The tube-bank is placed at the bottom of a vertical tank, which produces 3.4563 kg/s of saturated cyclohexane at 356.7 K. How may tubes are needed ... 

Vertical tanks. Those supported above ground are made with dished or conicai bottoms. Flat bottomed tanks rest on firm foundations of oiled sand or concrete. Supported flat bottoms usually are 1/4 in. thick. Roof plates are 3/16 in. thick. Special roof... 

When the maintenance crew returned to the job site a short time later, they observed a water stream forcefully squirting from the two 1/2-inch vents. They noticed this normally vertical tank leaning at a slight angle. The bottom bulged upward at the bottom-to-shell joint as much 8 inches (20.3 cm) above the foundation. Anchor nuts ripped through the anchor chairs, and catwalks attached to the tank roof had torn away from welded clips. 

The welder was directed to weld a patch-plate on the roof of the low-pressure, vertical tank. Heat from the welders torch vaporized and ignited some phenol which had accumulated on the underside of the roof and a mild explosion occurred. The overpressure tore some of the roof seam. Fortunately, the alert welder saw evidence of an internal fire and ran to safety just before the explosion occurred. [3]... 

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