Pressure Vessel Engineering Curriculum
Internals
Module from the Pressure Vessel Engineering Curriculum curriculum.
Module 9 - Vessel Internals (Trays, Packing, Cyclones) · Learning Objectives · 1. Select tray type by service (sieve, valve, fixed valve, baffle) · 2. Apply turndown, capacity, and efficiency criteria to tray selection · 3. Compare random vs structured packing: HETP, ΔP, fouling tolerance · 4. Design distributor and collector for packed columns (gpm/ft2) · 5. Apply FCC cyclone design for regenerator and reactor vapor cleanup · Tray Type Comparison
| Type | Turndown | Capacity % | Efficiency % | Cost | Typical Use |
|---|---|---|---|---|---|
| Sieve | 2-2.5 | 100 (base) | 65-80 | 1.0 | Clean service, low cost |
| Valve (moving) | 4-5 | 95-105 | 65-80 | 1.3 | Crude, variable rates |
| Fixed valve | 3-4 | 105-115 | 70-85 | 1.5 | Fouling, crude |
| Bubble cap | 6-8 | 75-85 | 65-75 | 2.5 | Low flow, rarely used |
| Dual flow | 2-3 | 110-120 | 55-65 | 0.8 | Fouling, crude bottoms |
| Packing Selection | |||||
| Packing | Type | HETP (ft) | Cap factor | Fouling | Use |
| Pall ring 2" metal | Random | 1.5-2.0 | 3.0 | Moderate | Clean service |
| IMTP 40 | Random | 1.3-1.8 | 3.2 | Moderate | High capacity |
| Raschig ring | Random | 2.5-3.5 | 2.0 | Low | Legacy |
| Mellapak 250Y | Structured | 1.0-1.3 | 3.5 | Low | Clean, tight sep |
| Mellapak Plus 752 | Structured | 0.9-1.1 | 3.8 | Moderate | High capacity |
| Flexipac 2Y | Structured | 1.1-1.4 | 3.4 | Low | Vacuum |
Source: Pressure_Vessel_Engineering_Curriculum_v1.xlsx · Sheet: Internals
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