Zero Emission IGCC with Rectisol®
Zero Emission IGCC with Rectisol technology
Presentation at the GTC 2002 in San FranciscoU.Koss, M. Meyer
Lurgi Oel.Gas.Chemie GmbH
Zero Emission IGCC with Rectisol®
TOC
Background
Why IGCC…..?
Why Rectisol?
CO2 Bulk Removal
Trace components, mercury
Plant Configuration
Features & Figures
The Presentation will cover…….
Zero Emission IGCC with Rectisol®
Background
Kyoto protocol is still alive- also the DOE finances considerable R&D activities
CO2 emission taxes are being discussed or in place
Primary focus on improving efficiencies, but …..... sequestration of CO2 might be necessary
Sequestration- in aquifers seems feasible- in oil fields (Enhanced Oil Recovery) is proven technology
Focus of interest:De-carbonization of coal based power production!
Zero Emission IGCC with Rectisol®
Why IGCC……..
Scrubbing CO2 from Flue Gas with MEA !?
…..when CO2 will have to be sequesterred?
Power producer´s favorized solution:
? ?
Zero Emission IGCC with Rectisol®
Estimated Figures for 500 MWel. / MEA Flue Gas Scrubbing 1) :
Flue Gas to be de-carbonized: 2 000 MM SCFDMEA Circulation Rate: 66 000 gpmLP Steam Consumption: 1 200 tons/hourMEA losses: 1 000-1 500 tons/year Loss in overall efficiency: 20 - 28 %
Trace component behavior: ?
Arrangement:- 6 Absorption towers, Φ 8 m - 12 Regeneration towers, Φ 6 m
CAPEX increased by: approx. 80 %
MEA Figures
1) Electrical Efficiency w/o de-carbonization 45 %, with de-carbonization 33 %
Zero Emission IGCC with Rectisol®
Why IGCC…..?
IGCC´s are proven technology
De-carbonized gas (hydrogen) generation is proven technology
Penalty for de-carbonization is low compared to other solutions
Synergies with removal of other contaminants lead to a
„Zero Emission IGCC“
Zero Emission IGCC with Rectisol®
Why Rectisol®?
Rectisol® Regeneration
H2SRectisol®
CO ShiftConversion
CO2Rectisol®
OxyClaus®
SRURefrigeration
Unit
Raw GasfromGasification
Fuel Gasto Turbine
Liquid CO2
Sulphur Product
CO2Liq.
Rectisol® Fuel Gas Conditioning Package:
Zero Emission IGCC with Rectisol®
Complete removal of H2S
Complete removal of trace contaminants
Excellent availability & cheap
No solvent degradation!
No environmental problems!
Your gas turbine likes it!
and
Best-suited for CO2 bulk removal
Rectisol® uses generic Methanol
Why Rectisol®?
Zero Emission IGCC with Rectisol®
CO2 Bulk RemovalSolvent Characteristics
0
5
10
15
20
25
30
35
40
0 0,2 0,4 0,6 0,8 1 1,2 1,4
CO2 Partial Pressure in MPa
CO
2 Loa
ding
in %
wt.
Chemical Solvents(Amines)
Selective physical Solvents
Rectisol®
Zero Emission IGCC with Rectisol®
CO2 Bulk RemovalSolvent Characteristics
0
5
10
15
20
25
30
35
40
0 0,2 0,4 0,6 0,8 1 1,2 1,4
CO2 Partial Pressure in MPa
CO
2 Loa
ding
in %
wt.
MEA, 25 wt% at 140 °FaMDEA®, 50 wt% at 158 °FSelexol® at 104 °F
Purisol® at 104 °FRectisol® at -4°F
Zero Emission IGCC with Rectisol®
0
5
10
15
20
25
30
35
40
0 0,2 0,4 0,6 0,8 1 1,2MPa
CO
2 Loa
ding
in %
wt.
CO2 Bulk RemovalFlash Regeneration
∆pCO2 available
Atm. Pressure Raw GasCO2 Partial Pressure
Rectisol® FlashRegenerationPotential (92%)
aMDEA® FlashRegenerationPotential (61%)
Selexol® Flash RegenerationPotential (90%)
Zero Emission IGCC with Rectisol®
It´s the small bugs that can bother you most!
Trace Contaminants
Carbonyls
COS
NH3
MercaptansHCN
Hg
CS2
VOC´s
Zero Emission IGCC with Rectisol®
Removed by……..
Absorption, e.g….
- Total Sulfur < 100 ppb (v)
- VOC not detectable!
- HCN below detection level (0.01 ppmv)
- NH3 below detection level
or
Temperature Trap:
- Inside Rectisol®, the Gas “sees” -76°F!
Trace Contaminantsin Rectisol®
Zero Emission IGCC with Rectisol®
1,E-10
1,E-09
1,E-08
1,E-07
1,E-06
1,E-05
1,E-04
1,E-03
1,E-02
1,E-01
1,E+00
1,E+01
-120 -80 -40 0 40 80 120 160 200 240
Temperature, °F
Hg
Part
ial P
ress
ure,
mba
r
Literature DataExtrapolated Curve
Rectisol
Elemental Mercury Vapor Pressure
Mercury
Zero Emission IGCC with Rectisol®
Non-elemental mercury precipitated in quench and cooling
Elemental mercury condensed in gas refrigeration or latestat cold absorber top
- theoretical figure: not detectable
- analytical figure: 1-2 ppb(v)(in standard Rectisol® / 340 psia)
- after dilution with combustion air: 0,1 - 0,2 ppb(v)
UK Environment Protection act: 200/ 600 µg/Nm3
OSHA limit: 50 µg/Nm3 ~ 6 ppb
=> no additional mercury removal process step needed!
Mercury
Zero Emission IGCC with Rectisol®
Plant ConfigurationBlock Flow Diagram
Zero Emission IGCC with Rectisol®
Plant Configuration
Rectisol® with integrated Clean Gas Shift
Gas Expander, providing double benefit:- energy recovery- refrigeration effect through cold expanded gas
Lurgi OxyClaus® SRU- approx. 30 % lower invest relative to air Claus- excellent drain for ammonia stripper offgas
Tailgas re-compression, i.e. Emissions-free sulphur recovery
No COS hydrolysis needed!
Technical Highlights
Zero Emission IGCC with Rectisol®
Plant ConfigurationPFD
Zero Emission IGCC with Rectisol®
Features & Figures
For producing 500 MWel
appr. 260 MM SCFD of Hydrogen Fuel have to be generated
appr. 360 MM SCFD of Raw Syngas have to be de-sulfurized
appr. 430 MM SCFD of Syngas have to be de-carbonized after the Shift Conversion
, assumed that…...
Efficiency “conventional” IGCC: ηel = 50 %
Efficiency drop “Zero Emission”: 7 %- points
Zero Emission IGCC with Rectisol®
Rectisol® plant- Solvent circulation rate: 4100 gpm- LP steam consumption: 39 tph- Electricity consumption (incl. Refrig.): 13 MW- one single train!
Shift conversion:- HP steam consumption: 170 tph- Electricity consumption: 1,4 MW
OxyClaus® : - Sulfur Production (quality “bright yellow”): 180 tpd - Oxygen consumption: 3,7 tph - Electricity consumption: 3,4 MW- MP steam production: 30 tpd- LP steam production: 6 tpd
Features & Figures
Zero Emission IGCC with Rectisol®
500 MWel.
Flue Gas Volume approx. 3000 MM SCFD
SO2 < 1 lb/h
VOC´s below detection limit
Mercury < 0.2 ppb(v) or < 0.013 lb/h
NOx depending on gas turbine design
CO2 10 - 30 tph or 20 - 60 g/ kWh 1)
1) CO2 emission “conventional” IGCC : 780 g/ kWh
EmissionsFeatures & Figures
Zero Emission IGCC with Rectisol®
Rectisol Absorber,at Sasol II, RSADiameter: 5.4 mHeight: 62 mOp. Press.: 23 barg
The largest single train
HP absorption in the World,
643,000 m³n/hof Feed Gas
per train
References
Zero Emission IGCC with Rectisol®
3 SGP Gasifiers100000 m³n/h Syngas
Rectisol®81000 m³n/h H2to NH3 Synthesis
CO Shift Conv.134000 m³n/h
UREA Plant,Quimigal, Portugal
References
Zero Emission IGCC with Rectisol®
Conclusion
“Zero Emission IGCC” withRectisol® Fuel Gas Conditioning Package
means
Very low CO2 emissions
Maximum single train capacities
No sulfur emissions
Complete removal of trace contaminants like e.g. COS, HCN, NH3, Hg…...
Highest possible overall efficiency among the IGCC processes with CO2 removal
Energy efficient recovery of pure CO2
Zero Emission IGCC with Rectisol®
What´s left?
Based on the results, the overall efficiency of theIGCC has to be re-calculated
In case H2S can be sequesterred together with CO2 ,concept may be changed toRaw Gas Shift followed by Standard Rectisol®
Remaining Technology Challenge:Hydrogen fuelled gas turbine
Zero Emission IGCC with Rectisol®
Thank you for your attention!
Zero Emission IGCC with Rectisol®
Standard Rectisol®for MEGAMMONIA
Zero Emission IGCC with Rectisol®
Solvent Characteristics
0
5
10
15
20
25
30
35
40
0 0,1 0,2 0,3 0,4 0,5 0,6 0,7 0,8 0,9 1 1,1 1,2 1,3CO2 Partial Pressue in MPa
CO
2 Loa
ding
in %
wt.
Rectisol® at -20°C
aMDEA®, 50 wt% at 70°C
MEA, 25 wt% at 60°C
Purisol® at 40 °C
Selexol® at 40 °C
Purisol® at 0 °C
Selexol® at 40 °C