Questions on Technology

Often, questions are received about particular aspects of distillation. This includes operation, troubleshooting, design, and construction. Short answers, specifically aimed at those questions are made. Some of the questions and responses are posted here. These responses apply to very specific situations, so be careful in applying them to your plant.

Questions and answers are posted as they arrive. This page is updated often. Please return to keep track of new technical information. In general, the most recent postings are listed first.

Questions should be sent via e-mail or use our contact information.

1. Vaporization limits in thermosyphon reboilers
2. Control of parallel condensers (non-symmetrical)
3. Mass-transfer unit approach to column design.
4. Fluid heating systems: vaporizer, stab-in, thermosyphon, forced, kettle
5. Vacuum system selection and pumparound control logic
6. Heat exchanger system selection criteria
7. Packing efficiency tests and interpreting the results to operating units
8. Liquid level measurement problems in an FCC main fractionator
9. Hanging downcomer high-capacity trays: what are they and how do they work?
10. Cascade control on distillation units: why use it?
11. Dry-out of a supercritical extraction unit.
12. Random packing hold-downs and open area for flow.
13. Structured packing application in high-pressure systems: limitations and experience.
14. Visbreaker wash zone coking: poor product quality (D8 color) from HVGO cut from a visbreaker vacuum fractionator.
15. Dual reboiler operation: removing the first reboiler of two reboilers from service while leaving it in place: petroleum refinery FCC naphtha stabilizer.
16. Thermosyphon reboiler operation: affect of liquid levels on heat duty in a recirculating system without a baffle: petroleum refinery naphtha splitter.