Tanks, elevated

Another type of aboveground tank is the elevated tank. These tanks, elevated by stmctural supports, are almost exclusively relegated to the domain of the municipal water supply companies. Because the municipal water supply is considered a vital pubHc resource, tanks are often elevated for the reason that gravity as a source of pressure is considered more reHable for distribution to the market. Although the same effect can be accompHshed by placing tanks on bills, where this is not possible the tanks are elevated by stmctural steel supports. 

American Water Works Association (AWWA) The association has many standards deahng with water handling and storage. A list of its publications is given in the AWWA Handbook (annually). AWWA DlOO, Standard for Steel Tanks—Standpipes, Reservoirs, and Elevated Tanks for Water Storage, contains rules for design and fabrication. 

Elevated Tanks These can supply a large flow when required, but pump capacities need be only for average flow. Thus, they may save on pump and piping investment. They also provide flow after pump failure, an important consideration for fire systems. 

On small installations an elevated tank above the furnace would be used (refer to Figure 37). The savings from eliminating the pumps, valving, and slurry lines are offset by the additional cost of a structure to support the tank and a rotary feed valve. The tank is fitted with a screened overflow. A dewatering screw conveyor is used for feeding the furnace. 

Some pieces of equipment will be elevated to simplify the plant operations. An example of this is the gravity feed of reactors from elevated tanks. This eliminates the need for some materials-handling equipment. 

A 4 hr storage capacity of cooling water will be maintained in an elevated tank on a nearby hill. This will provide enough water to properly cool all the reactors in case of a power failure. 

Elevated heat exchangers, 19 508 Elevated tank, 24 280-281 Elevated temperature precipitation heat treatment, aluminum alloys, 2 333 Elevator furnace, 12 288 Elgonidipine, 5 131... 

Elevated tanks can supply a large flow when required, but pump... 

The procedure was to clear the transfer fine of the waxy material with compressed air supply just before the transfer fine was put in service. On the evening of the accident, an operator connected an air hose to a 90 psig (6 bar) supply to clear the entire 200 meters (600 ft.) of feed line. The operator then walked to the elevated tank to determine if air could be heard rushing out of the tank vent. He heard nothing. The operator spoke to two maintenance employees working near the end of the 20-m3 (700 ft3 or 5,300 gallon) tank and left the area to find his supervisor. Shortly after that, one end of the tank blew off, and the two maintenance mechanics plunged some 40 ft. (12 m) to their deaths. [7]... 

The procedure was to clear the transfer line of the waxy material with a compressed air supply just before the transfer line was put in service. On the evening of the accident, an operator connected an air hose to a 90 psig (6 bar) supply to clear the entire 200 meters (600 ft.) of feed line. The operator then walked to the elevated tank to determine if air... 

The rakeless ultrahigh-rate thickeners use elevated tanks up to 20-m diameter. Advantages are no drive, high throughput rate, and the small footprint. Disadvantages are the height of the elevated tank. 

This procedure is used for calculating the distribution of vertical and horizontal forces due to wind or seismic loadings for vessels, spheres, elevated tanks, and bins supported on cross-braced legs or columns. 

Figure 6-21. Dimensional data and forces of bin or elevated tank.

Figure 6-23. Dimensions and loads for a liquid-filled elevated tank.

Figure 6-28. Typical support arrangements for bins and elevated tanks.

Procedure 6-3 Design of Square and Rectangular Platforms, 304 Procedure 6-4 Design of Pipe Supports, 309 Procedure 6-5 Shear Loads in Bolted Connections, 317 Procedure 6-6 Design of Bins and Elevated Tanks, 318 Procedure 6-7 Agitators/Mixers for Vessels and Tanks, 328 Procedure 6-8 Design of Pipe Coils for Heat Transfer, 335 Procedure 6-9 Field-Fabricated Spheres, 355 References, 364... 

In Chapter 10, we discussed fluid pressure and the role of water towers in small tovras. RecaU that the function of a water tower is to create a desirable municipal water pressure for household and other usage in a town. To achieve this purpose, water is stored in large quantities in elevated tanks. Also recall that the municipal water pressure may vary from town to town, but it genetaUy falls somewhere between 50 and 80 Ib/in (psi). In this assignment, use Excel to create a table that shows the relationship between the height... 

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