22-02-2023

Level measurement on distillation bottoms

The level measurement in the bottom of any distillation column is a critical measurement task in refineries. Tower internals damage due to the failure of level control technologies for residual bottoms is one of the most common issues in refineries. However, this is not the only way that reliable bottoms level measurements can save costs and increase efficiency in the refining process.

In the atmospheric distillation process as well as in vacuum distillation, crude oil is separated into fractions by temperature. The least volatile components descend to the bottom of the column, where it is important to measure the liquid level in order to avoid excessive height or falling too low. If the level is too high, this could lead to tray damage and decrease the quality of the products with large impacts downstream in other units. If the level is too low, this could potentially damage pump seals or even the pumps themselves. With the radiometric level systems from Berthold the bottoms can be reliably measured in a non-invasive and non-intrusive manner, regardless of process conditions changes or environmental changes.

Berthold has the best solution
Often, the level measurement on tower bottoms is carried out using differential pressure probes. Such devices require calibrations and often face issues with the plugging of pressure ports. Berthold offers a radiometric measurement solution, which does not have these issues and can easily be installed on existing columns without any process downtime. Typically an arrangement with a point source and a rod detector is applied here. In case of measurement ranges over 2 meters, our TowerSENS solution can be used to cover the entire span with just one set of wiring.

These are the advantages of Berthold's level measurement on distillation bottoms:
■ Reliable prevention of pump cavitation
■ Increased efficiency of distillation process
■ Safe prevention of foam or liquid entering the upper fractions
■ Unaffected by foaming, plugging, build-ups or changes in temperature or pressure
■ Easy to install on existing columns without process downtime