Floating tank storage

Figure 10.29 Fixed roof and floating roof storage tanks...

TANKS This program estimates volatile organic compound (VOC) and hazardous air pollutant (HAP) emissions from fixed- and floating-roof storage tanks. TANKS is based on the emission estimation procedures from... 

The latest research on storage tank fire protection is the LASTFIRE Project conducted in the UK. This joint industry project reviewed the fire-risk of large, open top floating roof storage tanks. For additional information on this project, refer to http //www.resprotint.co.uk/. 

Crude oils all contain some sulfur, mostly as thiols, sulfides, and hydrogen sulfide. The sulfur content ranges from about 6% for light Arabian crudes, to 1-2% for California crudes, down to as little as 0.4% for some Canadian Peace River crudes [60]. Loss of volatile sulfides of stored crude oil is also controlled by using floating roof storage tanks. 

A water tank storage device can be built, very much like those used to store methane in some rural areas. This consists of an inverted drum or tank within another tank or drum that is filled with water. As the gas fills the inner tank, the inner tank floats upwards in the water, and is kept from tilting by guide rails or guy wires. A stop keeps the tank from rising totally out of the water. For a more permanent setup, round concrete spring tiles can be put in the ground and a inverted tank inserted for larger area... 

The legs of the platform can be used as settling tanks or temporary storage facilities for crude oil where oil is exported via tankers, or to allow production to continue in the event of a pipeline shut down. The Brent D platform in the North Sea weighs more than 200,000 tonnes and can store over a million barrels of oil. Topside modules are either installed offshore by lift barges, or can be positioned before the platform is floated out. 

Storage of Flammable Materials. The preferred storage for flammable Hquids or gases is in properly designed tanks. Floating roof tanks frequently are used in the petroleum industry for flammable cmdes and products (see Tanks and pressure vessels). The vents on cone roof tanks should either be equipped with flame arrestors or the vapor space above the contents should be inerted with a nonflammable gas or vapor, unless the flash point is weU above the maximum ambient temperature, the contents are not heated above the flash point, and the tank is not exposed to other tanks containing flammable Hquids. 

API Publ 2026, Safe Access/Egress Involving Floating Roofs of Storage Tanks in Petroleum Service, 2nd ed., April 1998. 

At the beginning of the current reporting year, the facility installed a floating roof in its storage tank. This change reduced fugitive emissions from the tank 90 percent, from... 

A facility stores NFPA (National Fire Protection Association) Class 1B liquid in a diked atmospheric storage tank equipped with an external floating roof. 

In the storage of flammable liquids, if the composition of the vapour-air mixture above the liquid surface falls within the flammability limits, a floating roof tank would be used or the tank blanketed with inert gas. Check if the vapour composition for liquids listed below will fall within their flammability range, at atmospheric pressure and 25°C. 

In some cases the decision whether storage vessels will be equipped with a vapor recovery system has been determined by the United States Environmental Protection Agency (EPA). In 1973 it set the standards4,5 for all petroleum liquids that are stored in vessels of mcae than 65,000 gal (245 m3). It states that if the vapor pressure is greater than 11.1 psia (570 mm Hg) a vapor recovery system or its equivalent must be installed on any new tanks. If the vapor pressure is between 1.52 psia (78 mm Hg) and 11.1 psia (570 mm Hg), a floating head tank may be used or a vapor recovery system may be installed. Since the former is cheaper it will usually be selected. Below 1.52 psia (78 mm Hg) only a conservation vent or its equivalent is required. 

---