Topics

What Should Troubleshooters Focus On?

The most common column malfunctions: internals, operational, controls, installation. The top seven malfunctions: plugging, tower base, damage, startup/shutdown/commissioning, incorrect assembly, liquid distributors, intermediate draws.

Troubleshooting Tray Towers

Visualisation of vapour-liquid dispersions on trays, flooding entrainment, weeping. Flood mechanisms: jet (entrainment), system limit, downcomer backup, downcomer choke. Which one limits your capacity? Common tray types: sieve, moving valve, fixed valve. Which works well and which plugs easily in fouling applications? Gamma scans: application for diagnosing flood, missing and damaged trays, foaming and downcomer flooding. Do gamma scans ever lie? Flooding and foaming symptoms: which can be trusted? Liquid and vapour sensitivity field tests: identifying the correct flood mechanism. Downcomer unsealing and vapour cross flow channeling: when would they affect your tower?

Troubleshooting Packed Towers

Rule of thumb for flood pressure drop and packing efficiency. Grid gamma scans for detecting maldistribution, damaged packings, distributor malfunction, distributor and collector overflow. Distributor overflow: DEATH for packed beds. Some do’s and don’ts for distributors. Water testing distributors in the shop and in the field to identify and avoid distributor malfunctions. Surface temperature surveys: application for identifying maldistribution, verifying simulations, and troubleshooting reboilers and condensers. How to conduct and what to avoid.

Troubleshooting Distillation Controls

The material balance control concept and what happens when overlooked. Assembling control loops into an overall scheme: what works, what causes instability and what impairs efficiency. Can a tray-to-packing revamp fail due to inadequate control? Reboiler, condenser and pressure controls: which loops work and which misbehave. How poor piping can lead to unstable pressure control. Best temperature control location. How can a temperature controller be fooled? Control systems that did not work.

Tower Operational Malfunctions

Troubleshooting inlets and outlets: you don’t need an expert, you need a sketch. Tower feeds: how these can cause premature bottlenecks. Vapour entry into downcomers, pipes that obstruct downcomer inlets. Why submerged reboiler return inlets are a common source of premature flooding and of tray/packing damage. Good and bad practices. Can reboiler return impingement on liquid level prematurely bottleneck a tower? Pressure surges caused by water entering a tower full of hot oil or insoluble organics. Other common sources of tray damage. Liquid outlets: sources of vapour entrainment in column outlet liquid. Is it troublesome? Why must self-venting flow be assured in the presence of entrained vapour? How siphons form in liquid outlet lines.

Column Startup Problems

Some commissioning watchouts: pressuring, washing, drawing vacuum, introducing liquid, steam-water operations. Common startup and operation problems: precipitation, chemical reaction. Symptoms and cures. Common instrument problems:what to watch out for.

Troubleshooting Distillation Simulations

Does your simulation reflect the real world? How poor simulation leads to incorrect problem diagnosis. Reality checks that properly validate simulations. Use of mass and energy balances in troubleshooting and simulation validation.

Case Studies

These operating experiences will be scattered throughout to illustrate the key principles and to distinguish good from bad practices.

Special feature of this program...

In addition to the program workbook, every attendee will receive a copy of the Distillation Operation textbook. This material will be an invaluable reference source.