Module 8 - Turnaround Scope

Module from the Hydroprocessing Operations Curriculum curriculum.

TURNAROUND SCOPE — CATALYST CHANGEOUT & REACTOR INSPECTION · Learning Objectives · 1. Plan and execute catalyst unloading (vacuum and gravity methods) 2. Conduct reactor vessel and internals inspections during turnaround 3. Supervise catalyst reloading to achieve target density and level 4. Complete reactor closure and leak testing 5. Manage turnaround schedule for reactor work · Catalyst Changeout — Activity Sequence

Activity	Duration (days)	Crew Required	Equipment	Safety Requirements	Deliverables
Unit shutdown and cool-down	2-3	Operations (4-6)	N/A	Normal shutdown procedure, O2 monitoring	Shutdown log, temperature records
Inert and wash (N2/steam)	1-2	Operations (4)	N2 supply, steam	Confined space prep, atmospheric monitoring	Purge records, gas-free certificate
Reactor head removal	0.5-1	Riggers (4), mechanics (4)	Crane, torque tools, head stand	Crane lift plan, confined space entry permit	Reactor open for inspection
Catalyst unloading (vacuum)	2-5 per reactor	Catalyst crew (6-8), vacuum truck operator	Vacuum truck, hoses, nitrogen lance	Pyrophoric material handling, respiratory protection, inert atmosphere	Spent catalyst drums (weighed), unloading report
Reactor internals inspection	1-2	Inspector (2), FOS advisor	UT gauge, borescope, camera, measuring tools	Confined space entry, LOTO, fall protection	Inspection report: UT readings, visual findings, photos
Internals maintenance/replacement	1-5 (as needed)	Mechanics (4-6), welders	Welding equipment, new internals if needed	Hot work permit (if welding), confined space	Repair records, weld inspection reports
Catalyst loading (dense)	3-7 per reactor	Catalyst crew (8-12), crane operator	Dense loading equipment (Densicat), hopper, crane	Confined space, dust monitoring, respiratory protection	Loading report: quantities, densities, levels per bed
Reactor closure	0.5-1	Mechanics (4), torque crew	Torque wrenches, new gaskets, studs	Bolting procedure per PCC-1, stud verification	Torque records, gasket log
Pressure test	0.5-1	Operations + inspection	Test pump, pressure gauges, N2 supply	Test procedure per B31.3, safety perimeter	Test record (signed)
Commission and startup	5-10	Full crew	Per startup procedure	Full PSSR before hydrocarbon introduction	Startup log, PSSR checklist
Catalyst Loading Quality Control
Parameter	Target	Tolerance	Measurement Method	Corrective Action	Notes
Loaded Density	Per vendor spec (typically 42-52 lb/ft³)	±2 lb/ft³	Weigh each drum loaded ÷ bed volume	Re-level, add/remove catalyst	Dense loading achieves 10-15% higher density than sock loading
Bed Level	Level within ±1 inch across reactor diameter	±1 inch	Laser level or string line measurement at 8+ points	Re-level before next bed	Critical for distribution — uneven level causes channeling
Catalyst Quantity	Per BOM (Bill of Materials)	±0.5% of specified weight	Drum count × average drum weight	Reconcile with vendor, adjust grading if needed	Track cumulative weight vs plan throughout loading
Catalyst Integrity	No broken extrudates, dust, or contamination	<1% fines by visual inspection	Visual check of each drum before loading, screen at hopper	Reject damaged drums, notify vendor	Fines increase ΔP and reduce performance
Inert Ball Layers	Per loading diagram (size graduation per spec)	Correct size at each layer	Verify ball size matches diagram before placing	Replace incorrect size	Bottom: large → small (upward); Top: small → large (upward)
Temperature (catalyst in drums)	<120°F	Max 150°F for safe handling	IR thermometer on drums	Cool drums before loading if hot, check for self-heating	Presulfided catalyst can self-heat — monitor closely
Source: FOS Chief Files — Catalyst & Loading folder, Hydro Loadings, Catalyst_Loading_Best_Practices_v1.xlsx, Catalyst_Loading_Report_Template_v1.docx

Source: Hydroprocessing_Operations_Curriculum_v1.xlsx · Sheet: Module 8 - Turnaround Scope

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