~ Consider running between TAR’s with only spalling though a proactive approach
– EOR = 1175-1200degF
– 5 years between pigging
~ Delta Valve Info
– During an emergency shutdown, stagnant cooling water froze in the Delta Valve cooling box causing a bulge in the covers.
– Two instances of transition spool leakage at bottom flange face
~ Furnace Fouling
– Skin TI’s, Delta P
~ Reasons
– Feedstock CCR, Aromaticity, Salt
– Furnace Hot Spot, Flame Impingement, less XS02
– Process Low Velocity
~ Mitigation
– Chemicals
– CZ Alonizing – Inside
– Recycle
– Velocity Steam
– Metallurgy
– Furnace Design
– Preheat
– Outside Coating – Outside
~ No technology for venting
– Getting everyone away from the structure on a routine basis (unheading, cutting, switching)
~ Lowering pressure during venting of the drum
– EPA driven
– Options:
– Install liquid ring compressor
– Install injector
~ Foaming/Anti-foaming Injection
– Injection point 180 degrees from vapor outlet
– Carrier is HGO and LGO
– Throttle to hold pressure
– Standard outage one drum diameter
~ Minimum coking time
– 4 – 6 hours in the drum
– Achieve minimum temp of 910 to 920 for 30 minutes
– Restart coking process
– If too soon into drum, quench and drill
