catacarb section, dawood hercules fertilizers limited
DESCRIPTION
Internship Presentation of Process Gas Purification Unit in Dawood Hercules Fertilizers Limited, Sheikhupura, Pakistan.The plant is capable of producing 1350 MTPD of Urea, branded as BABBER SHER UREA.This report covers detailed process flow & instrumentation used in Carbon dioxide removal unit of Ammonia Section of the plant.Published online for knowledge sharing purposes. In case of any mistakes found, please feel free to contact.Kind Regards,Muddassir SultanTRANSCRIPT
Presented By: Muddassar Sultan
Catacarb Section
National University of Sciences & Technology
Catacarb Section It consists of following main equipments:
• High Temperature Shift Converter
• Low Temperature Shift Converter
• Desuperheater
• Absorber
• Stripper
• Rich Solution Flasher Drum
• Knock Out Drums
Following main operations are carried out:
• Conversion of CO to CO2.
• Removal of CO2 from Synthesis Gas.
High Temperature Shift Converter
• Reaction:
CO + H2O(s) H2 + CO2
• Conditions: o Inlet Temperature: 675oF - 700oF
o Outlet Temperature: 750oF
o Catalyst: Iron
o Pressure Drop: 5psi
• Composition:
Composition Inlet % Outlet %
H2 56.25 60.25
CO 12.38 2.18
CO2 7.96 16.24
Heat Exchangers
103-C
104-C
1112-C
BFW (Tube Side)
Methanator Feed (Shell Side)
BFW (Tube Side)
Bypass From HTS
To LTS
Low Temperature Shift Converter
• Reaction:
CO + H2O(s) H2 + CO2 (Continued)
• Conditions: o Inlet Temperature: 410 F
o Outlet Temperature: 435 F
o Catalyst: Copper
o Pressure Drop: 5psi
• Composition:
Composition Inlet % Outlet %
H2 60.25 61.2
CO 2.18 0.21
CO2 16.24 17.5
Operating Parameters
• Temperature in HTS should not exceed 950oF:
– Catalyst Inactive
– Vessel Damage
• Catalyst deformation is detected via pressure
drop
104-D
HTS
103-C
104-C
1112-C 108-D LTS
700o F
760o F
630o F
530o F
400o F
TRCE Control Valve
HTA
HCV
PB
From Reformer
To Desuperheater
Process Flow Diagram
PDIa-17
Desuperheater LTS effluent at 440oF is quenched to 350oF using process condensate
Desuperheater
1105 CA & CB
102-F
Raw Gas Separator vessel
To Absorber 440oF
350oF
260oF
Rich Solution
Lean Solution
Syn Gas CO2 free
Raw Syn Gas
101-E
Absorber:
HLA
LLA
LICe
•Low Temperature & High pressure
•Polypropylene Flexi rings & Stainless Steel rings packing
•Catacarb Solution is used to absorb CO2:
K2CO3 + CO2 +H2O 2KHCO3
•Other components of Catacarb solution are:
- K2CO3 (35%)
- Glycol (Defoamer)
- Corrosion inhibitor
- Diethanol Amine & Tertiary Ethanol Amine
(enhance absorption capacity)
Semi-Lean
AR
Lean Solution 16% CO2 Semi Lean 35%CO2
Rich Solution 75%CO2
1105C
A&B 1111C
Stripper: Rich Solution
Lean Solution
Semi-Lean
•High temperature & Low Pressure
•Polypropylene Flexi rings & Stainless Steel rings packing
•CO2 is stripped off the rich solution:
2KHCO3 K2CO3 + CO2 +H2O
•Three Exchangers are provided at the bottom to provide heat
•Air injection to regenerate reduced V2O5
•Glycol addition for avoiding foaming
CO2 to
Urea
LLA
HLA
LRe
Rich
Solution
Flasher
1103-E
Absorber Stripper
Gases
107-JT
PDIe HPDA
Rich Solution
Semi Lean Solution
Knock Out Drum Working
CO2 Recovery
• CO2 may be recovered by the flue gases out of the primary
reformer……..?
• CH4 + O2 CO + CO2 + H20
• Main Constituents of flue gases:
– SO2
– NO2
– CO
– CO2
Thank You For Your Attention…..!
Questions.…?