Low interface level

Elevation of low interface level shutdown (LILSD) is normally set at 150 mm from the bottom of the vessel however, it is always advisable to check the liquid residence time for LILSD. A too short liquid residence time will increase the chances of a gas breakthrough from the separator. Generally, 1 to 3 min residence time is adequate for the shutdown level. The same principle can be used to set the low liquid level shutdown (LLLSD). This setting also depends on tire type of separator being used. For the flooded weir separator, this level can be set either above or below the weir level, depending on the residence time requirement. 

A low interface level (LIE) is usually used to raise an alarm for the operator s intervention. The required distance and liquid residence time between LIE and LILSD depends on the fluctuation of the incoming liquid and the possible liquid withdrawal rate. Eor a relatively steady flow, a 150 mm gap between LIE and LILSD is often used, with a liquid residence time ranging from 1 to 3 min. A low liquid level (LLL) can also be set for a 1 to 3 min residence time. Like LLLSD, LLL can also be set either above or below the weir level, depending on the application. 

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See also in sourсe #XX -- [ ]

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