Startup Sequence

Chapter from the FCC Operations Guide.

FCC STARTUP SEQUENCE OVERVIEW

Typical FCC Startup Steps

Phase	Step	Objective	Key Parameters	Duration	Critical Checks	Next Step Requires
1. Pre-startup	Mechanical completion & punch	All work complete, blinds removed	Punchlist zero safety items	Weeks	Safety walk-down	All items closed or accepted
2. Pre-startup	Instrument loop checks	Verify all instruments function	Every loop in unit	Days	100% completion	Signed loop check sheets
3. Leak test	Pressure test, leak check	System integrity verification	Test pressure, hold time	1-3 days	Zero leaks on safety systems	Successful hold test
4. Dry-out	Regenerator refractory dry-out	Remove moisture from refractory	Ramp rate per refractory vendor	2-5 days	Temperature ramp control	Target temperature achieved and held
5. Catalyst loading	Load catalyst inventory	Fill regenerator to operating level	Catalyst quality, level	1-2 days	PSD, activity, metals on fresh catalyst	Target inventory loaded
6. Circulation	Establish catalyst circulation	Verify circulation, slide valves, standpipes	Catalyst flow, ΔPs, temperatures	4-8 hours	Stable circulation, instrumentation OK	Stable at target circulation rate
7. Heat-up	Heat to operating temperature	Bring regen and reactor to cracking temperature	Torch oil or start-up burner	8-24 hours	Ramp rate, uniform heating	Regen >1,050°F, reactor >700°F
8. Feed introduction	Introduce hydrocarbon feed	Begin cracking operation	Feed rate, temperatures, yields	2-4 hours	Stable operation, no carryover	Stable at minimum feed rate
9. Lined out	Increase to design throughput	Full rate operation	All operating parameters	4-12 hours	All parameters within limits	Performance test conditions

Source: FCC_Operations_Guide_v1.xlsx · sheet “Startup Sequence”

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