calaculation of stripping index of catacarb system using Excel.

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Catacarb Stripping index calculations
and ways of improvement
Aug 2022
Intern: Anfal Zafar
Mentors:
Waqas Iqbal (SIC)
Usama Majeed(SS)
Unit Manager: Meer Salam Mudassar

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Catacarb System

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Stripping Index
Amount of energy to remove 1 lb mole of CO2 from stripper.
E-2508-Reboilers
76.67 MMBtu/hr
Heat from ejectors
65.03 MMBtu/hr
Heat of 40# steam
32.9 MMBtu/hr
Heat Input to Stripper C-2515
E-2508-Reboilers Heat from ejectors Heat of 40# steam
Heat Inputs to Amm-2 Stripper
Major heat input sources to Stripper are as followings:
 Heat input from reboilers E-2508
 Heat input from ejectors of 60# steam
 Heat of 40# steam

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Heat Input Sources At FEL 154% At FEL 125%
Heat from E-2508 (Reboilers) 55.79 MMBtu/hr 76.67 MMBtu/hr
Heat from ejectors 66.95 MMBtu/hr 65.03 MMBtu/hr
Heat from FR-413 51.7 MMBtu/hr 32.9 MMBtu/hr
Total Heat Input 174.33 MMBtu/hr 173.61MMBtu/hr
CO2 flow 202.9 KPPH / 4611 lbmol/hr 168 KPPH / 3818 lbmol/hr
Stripping Index 37.83 MMBtu/hr 45.47 MMBtu/hr
Stripping Index Calculation
Comparison of Stripping Index @ FEL 154 %Vs 125%

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 Stripping index requirement w.r.t load chart should be configured at DCS.
 From following table, it is evident that at 125% FEL compartment pressure is lower @PT-706/707
so these two ejectors should be cleaned in FAO
Recommendations

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Thank-You!