Hot Restart Following a Furnace Trip

Authors

Bryan McVicker

Matt Boian

Abstract:

A hot restart is the result of an unplanned shutdown or protective system “trip” of an online furnace. Coke deposited in the radiant coils, inherent to steam cracking reactions, leaves the coils vulnerable to brittle fracture damage as the furnace cools. Radiant coil damage can lead to higher consequence events including but not limited to a hydrocarbon loss of containment and firebox flooding. A safe, rapid restart is therefore desirable to protect against event escalation and must be balanced with the risk inherent to furnace startup operations.

This presentation intends to summarize the key items that should be considered when attempting to restart a furnace following an online trip. These items rely in part on successful execution of observations and tasks by responding personnel on the DCS console and in the field and therefore necessitate the availability of critical information and training.

Proper management of hot restart risk increases in difficulty during an upset involving multiple furnaces. A method for quickly establishing furnace restart priority will be discussed including an example of integration into a site DCS interface.

Furnaces in the context of this paper are referring to Pyrolysis Furnaces, also known as Steam Crackers.