Storage tanks and vessels

Equations for estimating the f.o.b. purchase costs of spherical pressure vessels, based on just the vessel volume, are included in Table 16.32 for two different pressure ranges. 

In some chemical processes, operations are conducted at pressures less than ambient. To achieve such pressures, vacuum systems are required. Pressures below ambient are commonly divided into four vacuum regions  

Of greatest interest to chemical processing is the rough region, which covers most polymer reactors, vacuum distillation columns, vacuum stripping columns, pervaporation membrane separations, vacuum-swing adsorbers, and vacuum crystallizers, evaporators, filters, and dryers. 

System Type Lower Limit of Suction Pressure (torr) Volumetric Flow Range at Suction Conditions (ftVmin) 

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Contrac tors bids offer the most rehable information on cost. Order-of-magnitude costs, however, may be required for preliminary studies. One way of estimating them is to obtain cost information from similar facihties and scale it to the proposed installation. Costs of steel storage tanks and vessels have been found to vaiy approximately as the 0.6 to 0.7 power of their weight [see Happel, Chemical Process Economics, Wiley, 1958, p. 267 also Williams, Chem. Eng., 54(12), 124 (1947)]. AU estimates cased on the costs of existing eqiiipment must be corrected for changes in the price index from the date when the equipment was built. Considerable uncertainty is involved in adjusting data more than a few years old. 

Refrigerated vessels handling flammables should also be provided with fixed fire protection in a manner similar to that of other storage tanks and vessels. Water spray protection or fireproofing of vessel surfaces that could be fire exposed should be considered. Where fireproofing is used, it should be specified for a fire endurance rating of 1 hr. 

Spillage due to transfer line breakages can be prevented by the installation of automatic shut-off valves inside storage tanks and vessels. 

ASME Code Sec. Ill Nuclear Power Plant Components This section of the code includes vessels, storage tanks, and concrete containment vessels as well as other nonvesseJ items. 

Provide adequate fixed fire protection for tanks and vessels containing flammable, unstable or reactive materials. This can include fire loops with hydrants and monitors in the storage area, foam systems for individual tanks, and deluge spray systems to keep the exposed surfaces of tanks cool in case of fire in an adjacent tank. 

Storage tanks and surge vessels for MEA must have inert blanket-gas systems. Sweet natural gas or nitrogen can be used as the blanket gas. This is required because MEA will oxidize when exposed to the oxygen in air. 

Flame arresters on outdoor reactors, storage tanks, and process vessels may be of the in-line, deflagration type with a short vent pipe connected in... 

Brewing Austenitic steels are used in fermentation vessels, storage tanks and attemperators, in yeast processing, and for transport tanks and barrels. 

Above ground (internal surfaces only) Surface and elevated water storage tanks condensers and heat exchangers hot-water storage tanks, processing tanks and vessels hot- and cold-water domestic storage tanks breweries and dairies (pasturisers). 

The ASME Boiler and Pressure Vessel Code, Section VIII, is the standard resource for the design, fabrication, installation, and testing of storage tanks and process vessels rated as pressure vessels (i.e., above 15-psig design). ASME B31.3 is a basic resource for process piping systems. 

The facilities consist of storage tanks or vessels, loading racks (or unloading) by ship, rail or truck, metering devices, and pumping or compression systems. Their capacities are relatively smaller compared to refinery storage and are normally dictated by local commercial demands in the bulk storage location. 

Where relief valves are provided on liquid storage tanks or vessels, where there is a possibility of liquid release, i.e., liquid slug, careful evaluation of the release disposal system (e.g., flare header) needs to be undertaken. In some cases, a liquid slug may block a header from releasing pressure and defeat the purpose of the pressure release system. 

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