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 noncontact technology is ideally suited for this kind of application since dust and temperature have no impact on measurement performance.
- 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
- Noncontact, nonintrusive technology
- No re-calibrations 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
SIL certified option
The SENSseries LB 480 detectors offer versions that are certified for use in SIL2 applications. SIL3 is achieved by adding an identical redundant SIL2 detector using the same source for homogenous redundancy. The certificate covers all measurement applications, from high level or low level alarms to continuous level. Thus the safe measurement of critical processes is guaranteed.
A reliable measurement, requiring no recalibration, is vital for the operation of the FCC, and is our highest priority. Berthold’s detectors offer stability in the face of changes in ambient temperature. Even drastic temperature shifts, e.g. from winter to summer do not cause measurement drift. Our patented method for detector stabilization compensates for temperature changes and aging.
Radiation Interference Protection (XIP)
With this function, weld tests no longer cause sudden fluctuations in the measured value. When weld tests are detected, the measured value is frozen until the external radiation event ends. A digital output can be set to signal the detection of interfering radiation.
All of our level measurement detectors are equipped with XIP.
Vessels that use radiometric devices in the FCC besides cyclone separators include electrostatic precipitation hoppers and the FCC fractionator tower bottoms. The radiometeric level measurement on the fractionator tower bottom is unaffected by the changing percent catalyst fines, unlike differential pressure detectors. This increases the reliability of the level, proventing tray damage if level gets too high, or pump damage if level were to become too low. Level and density measurements of the fluidized bed in the standpipe are also an often required measurement task in the FCC.