Measuring level in distillation bottoms

The oil that is not fractionated ends up in the bottom of the column, where the liquid level is important to measure, to prevent the level from being either too high or too low. If the level is too high, this could lead to tray damage and cause quality issues with products. If the level is too low, this could potential damage pump seals or the pumps themselves. By using the radiometric level systems from Berthold the residue can be reliably measured in a non-contacting manner, regardless of temperature and pressure changes.

Customer benefit

  • Stable level conditions
  • Avoid foam or liquid entering the upper fractions
  • Increased efficiency of distillation process
  • Highly reliable measurement, not affected by temperature and process density changes, pressure changes or foaming
  • Easy to install on existing columns, without process downtime


  • Continuous level measurement, typically 2…4 m measuring range
  • Installed on the cylindrical bottom of the column
  • Due to the importance of the measurement a redundant setup is often used
  • Typical arrangement uses Cs-137 point sources and scintillation rod detectors
  • On small diameter columns Co-60 rod rod sources achieve best measurement results

Berthold has the best solution

Though there are several cost effective ways to carry out this measurement using Berthold Technologies’ non-contacting, non-intrusive radiometric systems. One way is to use a single, continuous detector/point source (fan-beam) shield and source to cover the measurement range. If the range is longer than 3 meters, Berthold's LB 480/490 TowerSENS can be used to ensure the required span is entirely covered. A second redundant radiometric level measurement is used arranged at 90° to the first one.
Regardless of which Berthold solution you choose, a reliable and highly repeatable measurement is assured—without the possible repair costs and downtime that comes with contacting instrumentation.


Measurement solutions for the refining industry Brochure

Englisch | PDF | 3.0 MB

Whitepaper-radiometric-measurement.jpg Whitepaper

English | JPG | 76.1 KB