Storage Tanks and Tank Farms

The process equipment train consisted of a storage tank farm, an initiator pot, some small addition pots and a reactor. Multiple processes were run in the system and the equipment and instrumentation had to handle a variety of... 

This concept book is intended for nse by chemical engineers and other technical personnel involved in the design, operation, and maintenance of facilities and eqnipment where deflagration and detonation arresters (DBAs) may be reqnired. These people are nsnally technically competent individnals who are aware of, bnt not experts in, combnstion phenomena. The facilities where snch devices may be needed inclnde chemical plants, petrochemical plants, petrolenm refineries, pharmacentical plants, specialty chemical plants, storage tank farms, loading and nnloading facilities, and pipelines. 

Metallic lead is occasionally used as an extruded sheath to provide protection against chemical corrosion where it is necessary to bury cables in polluted or aggressive soils. Examples of these are found in chemical plants, refineries, storage tank farms and areas that have high water tables. 

Another means of protecting against the explosion hazard in flammable atmospheres is to employ gas detectors. The principle is that the gas detectors detect flammable gas/air mixtures at a low percentage, typically 10%, of the LEL and cause an alarm to sound. If the concentration reaches 25% or so of the LEL, the system automatically initiates a shutdown of the process. This type of technique is commonly used in process plants such as oil and gas refineries, LEG storage tank farms, chlorine doping rooms in water treatment plants, and on vehicles such as electric fork lift trucks operating in Zone 1 and 2 areas. 

Tank installations with underground storage tanks and station piping should, if possible, be provided with conventional cathodic protection [3]. This is sometimes not possible because electrical separation cannot be achieved between the protected installation and other parts of the plant (see Section 11.4). The necessity for cathodic protection can be tested as in Ref. 13. In tank farms, a distinction should be made between coated, buried storage tanks and aboveground, flat-bottomed tanks in which the base contacts the soil. 

Further chapters cover in detail the characteristics and applications of galvanic anodes and of cathodic protection rectifiers, including specialized instruments for stray current protection and impressed current anodes. The fields of application discussed are buried pipelines storage tanks tank farms telephone, power and gas-pressurized cables ships harbor installations and the internal protection of water tanks and industrial plants. A separate chapter deals with the problems of high-tension effects on pipelines and cables. A study of costs and economic factors concludes the discussion. The appendix contains those tables and mathematical derivations which appeared appropriate for practical purposes and for rounding off the subject. 

Texaco Limited, Canvey Island tank farm on the west side of the methane terminal is used to import petroleum products by sea via the two jetties, store and distribute them by tanker-trucks and sea, but mostly by the U.K. oil pipeline. The storage capacity is 80,000 tonnes of petroleum products employing about 130 people. 

The tank farm consisted of four storage vessels located approximately 15 m (50 ft) from a production building (Figure 2.19). A warehouse and a boiler house were on the opposite side of the vessels. On January 2, 1969, at 1 50 p.m., one of the vessels (C) was filled from the production plant. During filling, the vessel exploded (2 24 p.m.). Some minutes later, another vessel (D) also exploded. 

Dairy farms have bulk-storage tanks with their own refrigeration plants. These are usually made in the form of a double-skin, insulated tank, having the evaporator coils in the jacket, which also contains water. The refrigeration system runs throughout the 24 hours and... 

Storages for raw materials and products tank farms and warehouses. 

Storage vessels are usually located on tank farms. The space around a tank and the distances to other equipment depend on the materials stored, their potential hazardousness and the possibility of the unexpected changes in storage conditions. Fluid storages should be in a safe location away from process and public areas. It is also important to prevent fire spreading between tanks by keeping the level of heat radiation in an acceptable level (Mecklenburgh, 1985). 

After products are produced by refining they are further enhanced in a blending unit. In this unit the finished products are made by mixing the components in blending tanks. To gasoline for example, coloring dyes or special additives maybe added. The completed blends are tested and then routed to tank farm storage or shipment. 

Unidentified release in tank farm lead to storage tank fires and BLEVEs... 

Tank farm areas require additional consideration for spacing not only between other process hazards but from other storage tanks. Minimum shell to shell spacings for storage tanks are provided in NFPA 30. It also includes requirements for minimum spacings from other exposures such as property lines and buildings. 

A major factor in location of storage tanks within a tank farm is the topography of the tank farm area. The slope of the natural topography can be used to assist in the drainage requirements for a diked area and minimized the accumulation of spilled liquids near a storage tank. Diversion dikes or curbing can be used to divert spillage so it runs off remotely to a safe location. 

Assuming that only 1% of the -hexane of motor fuels is released to environmental media, such releases could be on the same order of magnitude as the total amount of relatively pure -hexane associated with the major end-uses described in Chapter 4. In addition to emissions to the atmosphere, releases from heating and motor fuel uses to other environmental media are possible as a result of leaks and spills at refineries, pipelines, large tank batteries (or tank farms ), above- and below-ground storage tanks, tanker trucks and railroad tanker cars, or from minor releases at garages or around homes and workplaces. Crude oil spills also result in the release of -hexane to the air or other environmental media. 

A 245-acre crude oil refining, processing, and storage facility located adjacent to the site discussed in Section 12.5 is bordered by other refineries and aboveground tank farms, and changed ownership around 1991. The site was initially characterized... 

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