Capacity Increase of Urea Plants
Thomas Krawczyk, Uhde Dortmund
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
Outline
o
Targets and requirements of a revamp
o
Revamp concept for a capacity increase of 17% (1925-2250 MTPD)
o
Contractor‘s input
o
CO2 generation
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
2
Targets and requirements of a revamp
Capacity increase
– By using existing margins to get maximum possible additional product with the lowest effort
necessary
– Elemination of bottlenecks
Reduction of energy consumption (e.g. heat integration)
Environmental improvements
– Reduction of emissions (to comply with new laws and international standards)
Increase of reliability and availability
Utilization of a well proven and reliable technical concept
Short as possible implementation downtime for modifications and new equipment
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
3
Revamp targets
Granulation
Melt Plant
actual design
revamp
actual design
revamp
Plant I
STAC
1925 mtpd
+ ~17%
2250
MTPD
UFT
2000 mtpd
+ 12.5%
2250
MTPD
STAC
1925 mtpd
+ ~17%
2250
MTPD
STAC
2000 mtpd
+ 12.5%
2250
MTPD
Plant II
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
4
The basis before the revamp for both plants
Conventional Stamicarbon CO2 Stripping Process
Condensate
LP
LP
absorber
absorber
Reactor
Reactor
To atmospheric absorber
WC
S
From recirculation
WC
HP
HPScrubber
Scrubber
C
HPCC
HPCC
S
C
NH3
To recirculation
CO2
Air
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
5
HH
2 Removal
2 Removal
Stripper
Stripper
Block Diagram Plant I & II (MP Section)
NH3
CO2
CO2
Synthesis
Synthesis
Carbamate
Pur. Process Cond.
urea solution
carbamate
20wt% water
LP
LPRecirculation
Recirculation
MP
MPSection
Section
carbamate 30wt% water
Parallel
Parallel
LP
LPRecirculation
Recirculation
Desorption
Desorption
Evaporation
Evaporation
Parallel
Parallel
Desorption
Desorption
Granulation
Granulation
1925 MTPD +17% 2250 MTPD
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
6
waste heat
Revamp concept 1925 2250 MTPD
To LP absorber
Reactor
Reactor
new equipment
WC
S
carbamate 20wt% water
WC
HP
HPScrubber
Scrubber
C
HPCC
HPCC
After
Afterreactor
reactor
S
NH3
C
To recirculation
CO2
Stripper
Stripper
Air
CO2
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
7
MP Section
MP Section (operating at ~20bar)
MP
MPPre-Evaporator
Pre-Evaporator
To 2bar Absorber
From synthesis
Level
LevelTank
Tankf.f.MPCC
MPCC
MP Rectifying
MP Rectifying
Column
Column
MPCC
MPCC
MP Stripper
MP Stripper
HP
HPCarbamate
CarbamatePump
Pump
To synthesis
CO2
To recirculation
MP
MPCO
CO2 2Compressor
Compressor
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
8
new equipment
Granulation Revamp 2000 2250 MTPD
Bucket
Bucket
elevator
elevator
Screen
Screen
Process
Granulator
scrubber
Cooler
scrubber
condensate
to US
tank
Startup
bin
Water injection
Fluidising air
Air cooler
NH3
Crusher
Crusher
Granulator
Safety
screen
Final
Cooler
Atomising air
NH3
Air
First Cooler
C
NH3
S
Urea solution
from evaporation
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
9
new equipment
To storage
Air cooler
Air
Overview of the revamp measures for plant I & II
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
10
Overview of the revamp measures for plant I & II
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
11
Uhde‘s input to optimise the concept
1925 MTPD
Case 1: before revamp
One pump in operation
One pump stand-by
A
in operation
B
stand-by
HP NH3 / Carbamate Pumps
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
12
Uhde‘s input to optimise the concept
2250 MTPD
Case 2a : after revamp
Two pumps in operation
Fall back to capacity before revamp in case
of malfunction or maintenance
Case 2b : after revamp
Two pumps in operation
One pump stand-by
Production remains at revamp capacity
A
in operation
B
in operation
C
stand-by
HP NH3 / Carbamate Pumps
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
13
Uhde’s modifications of closed cooling water loops
Lower water temperature in order to reduce fouling on CW side.
55°C
80°C
TIC
Circ.
Circ.Cooler
Coolerf.f.225E003
225E003
229E006
229E006
MP
MPCarbamate
CarbamateCondenser
Condenser
225E003
225E003
90°C
CW
65°C
225P010
90°C
new
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
14
Circ.
Circ.Water
WaterPump
Pumpf.f.225E003
225E003
229P006
229P006
CO2 and NH3 for Urea Production
Production
of ammonia plant is typically with lower ratio CO2 / NH3
(1.14 t/t for ideal process with no loss and pure CH4 as feedstock)
Demand
of urea plant per ton of urea: 0.566 t NH3 + 0.733 t CO2
⇒Ratio CO2 / NH3 needed: 1.29 t/t
Ammonia
plant
Ammonia
plant
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
15
CO2
NH3
CO2
NH3
Urea
plant
urea
Urea
plant
urea
Ways of CO2 Production
oo Standard
IncreasedAmmonia
CO2 production
Process
by
increasedofthroughput
recovery
CO2 from flue
of CO
gas
2 removal and return of
excess synthesis gas to reformer fuel
CO2 recovery
CO22 to urea
CO2 flue gas
NG feed
Reforming
NG fuel
CO shift
CO2 removal
Syngas return as reformer fuel
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
16
Purification
Synthesis
NH3
Conclusion
Changes
–
in one place always lead to changes in another place
Overall knowledge
Many
–
constraints in an existing plant and set by the existing periphery
Collaboration between all involved parties
Input
–
to optimize the revamp concept for a tailor-made solution
Expierenced contractor
Thank you for your attention!
[email protected]
www.uhde.eu
Capacity Increase of Urea Plants
24th AFA Int’l. Technical Fertilizers Conference & Exhibition
22 – 24 November 2011, Amman, Jordan
T. Krawczyk
17