Measuring level in distillation tower bottoms

Residual oil that is fractionated out ends up in the bottom of the tower, and it is control liquid level. If the level is too high, this could lead to tray damage and cause product quality issues. If the level is too low, this could potentially damage pump seals or the pumps themselves. By using the radiometric level systems from Berthold, residuel level can be reliably measured in a non-contacting manner, regardless of temperature and pressure changes.

Customer benefits

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

Characteristics

  • Continuous level measurement, typically 2…4 m measuring range
  • Installed on the cylindrical bottom of the column below trays and packing
  • 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

There are several ways to carry out this measurement using Bertholds’ non-contacting, non-intrusive radiometric systems. The most common and cost effective way is to use a single rod detector with a point source in a fan-beam shield. If the range is longer than 2 meters, Berthold's TowerSENS can be used to ensure the required span is entirely covered with only one electronics head. Another option is to use a rod source and point detector, or even a rod source and rod detector for the greatest sensitivity and lowest source activity. 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.

DOWNLOADS

Measurement solutions for the refining industry Industry brochure

Englisch | PDF | 3.0 MB

Radiometric measurement - Accuracy, repeatability and errors Whitepaper

English | PDF | 1.8 MB