Automatic tank gauging system

U.S. EPA, Automatic Tank Gauging Systems for Release Detection Reference Manual for Underground Storage Tank Inspectors, EPA 510-B-00-009, U.S. EPA, Washington, 2000. 

Automatic tank-gauging systems are found in almost all tank farms for inventory monitoring. The wire-guided float tape gauge systems are most... 

Operators of Buncefield-type sites should protect against loss of containment of petrol and other highly flammable liquids by fitting a high integrity, automatic operating overfill prevention system (or a number of such systems, as appropriate) that is physically and electrically separate and independent from the tank gauging system. 

A high integrity overfiii prevention system shouid, as a minimum, provide a ievei of SiL 1 as defined in BS EN 61511 -1. To reduce risk as iow as reasonabiy practicabie the overfiii prevention system shouid preferabiy be automatic and shouid be physicaiiy and eiectricaiiy separate from the tank gauging system. Automatic overfiii prevenfion may inciude, but not be restricted to, measures such as automatic shutdown of the suppiy iine or automatic diversion of the flow to another tank. 

Dutyhoiders wiii need to prepare a robust demonstration that aiternative measures are capabie of achieving an equivaient ALARP oufcome fo an overfiii prevention system that is automatic and physicaiiy and eiectricaiiy separate from fhe tank gauging system. 

Unexpected product movements can then be signaled to the operator by an alarm. Statistical analysis of static data from the tank-gauging system and dynamic data from flow meters could also be used to improve the accimacy of the tank capacity table. Cross-correlation of gauges versus fiow meters could further reduce measurement uncertainties. With high-accuracy tank-gauging instruments combined with powerful computing platforms, automatic reconcihation becomes realistic. 

Windsock to determine which way wind is blowing Automatic temperature controls to prevent overheating Pressure relief system to deal with excessive pressure Gauges and indicators to provide information about the state of the process Flares and scrubbers to burn off or neutralize released gas Positive pressure and filtered air in some units to protect employees Spare tank for runoff Emergency showers Eyewash fountain... 

In electronic balances the force exercised by the load on the base is measured with a force measurement cell (for example, an electrical strain gauge) and transformed into an electrical signal. This signal is processed within the balance in a digital or analog fashion and is then displayed. These systems can be calibrated and used in fully automatic installations. As force measurement cells one can use pressure sensors with lower requirements for accuracy. These are installations in which the weight is transformed into pressure pneumatically or hydraulically one can determine levels in tanks or reaction vessels by this method, which can also be used to meter automatically the main ingredients of a batch process, for example the water and monomer phase in an emulsion or suspension polymerization. 

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