Berthold's solution for fluid catalytic cracking (FCC) processes

Graphic of Fluid catalytic cracking unit FCC process

Level measurement of catalyst fines in cyclone separators

Catalyst fines have to be removed from the regenerator flue gas to fulfill regulatory requirements and to protect downstream equipment. Thus cyclonic separators are used to filter out the remaining catalyst fines. The solid particles settle down at the bottom of the separator, where their level is controlled by radiometric level systems from Berthold. The non-contacting technology is ideally suited for this kind of application since dust and temperature have no impact on the measurement performance.

Customer Benefit

  • Improved catalyst removal
  • Reliable process control
  • Ideal utilitzation of vessel capacity


  • Continuous level measurement, typically 2...4 m measuring range
  • Installed at the bottom conical part
  • Typical arrangement uses Cs-137 point sources and scintillation rod detectors
  • Non-contacting, non-intrusive technology
  • No re-calibrations, no maintenance required

Article "Made to measure"

Catalytic cracking, especially fluid catalytic cracking (FCC), is one of the most important conversion processes used in the refineries. To ensure a control of the entire cracking process, level measurements are essential. But the extreme process conditions of a fluid catalytic cracking unit pose some challenges for the measurement technology. The article “Made to measure” (published in the journal Hydrocarbon Engineering April 2020) explains why the use of radiometric measurement systems can help to optimize level control in FCCUs and how Berthold systems can help you to control your process more reliably to ensure safe operation while increasing efficiency.

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SIL certified option

The SENSseries LB 480 detectors are certified for use in SIL2 applications. Even SIL3 is achieved with homogenous redundancy. The certificate covers all measurement applications, from high level or low level alarms to continuous level measurement and density measurement. Thus safe operation of critical oil and gas processes is guaranteed.

More about SIL


Long-term stability

A reliable measurement, requiring no maintenance and re-calibration, is vital for the operation of a process and is therefore, our highest priority. Berthold’s detectors operate absolutely stable irrespective of changes in ambient temperature. Even drastic temperature shifts, e.g. from winter to summer don’t irritate the measurement drift. Our patented method for detector stabilization compensates for temperature influences and aging.

Detector Stability

Radiation Interference Protection (XIP)

With this feature, radiometric welding checks do no longer interfere the measured value. The measured value is frozen until the radiation interference detection is over. A digital output signalizes the detection of radiation interference. All Berthold level and level switch measurements are equipped with XIP.

More about XIP


Further applications

Vessels that use radiometric devices in the FCC besides cyclone separators are electrostatic precipitation hoppers and fractionator tower bottom level. The radiometeric level measurement on the fractionator tower bottom is unaffected by the changing percent catalyst fines like differential pressure. This increases the reliability of the level potentially proventing tray damage if level gets too high, or pump damage if level gets too low. Level and density measurements of the fluidized bed in the standpipe is also an often required measurement task.


Radiometric measurement Whitepaper

English | PDF | 1.8 MB

Article made to measure Publication

English | PDF | 6.8 MB