LATROBE UREA PROJECT Challenges posed from using...
Transcript of LATROBE UREA PROJECT Challenges posed from using...
Fourth International Conference on Clean Coal Technologies CCT2009
3rd International Freiberg Conference on IGCC and XtL Technologies
Dresden Germany 18-21 May 2009
Ltd
Dr David CrazeLatrobe Fertilisers Limited6-8 Powlett Street, East Melbourne VIC 3002Tel: 613 9415 7844 Fax: 613 8415 0351
LATROBE UREA PROJECT
Challenges posed from using Lignite Feedstock
Regional Urea Market ~ 0.5 Mtpa
Latrobe Valley 53 Bt of “Economic Coal”
Current Electricity Cost A$35-45/MWh
Depletion of Esso/BHP Gas & Oil Fields offers Potential for Future CO2 Geo-sequestration
Victoria’s Electricity Demand to Increase by 50% in 15 years
Project Locale
Latrobe Urea Project
MAIN OUTSET OBJECTIVES:
Economic Plant Size for Local Market plus Potential Export Product
Use of Proven Technologies
Enabled for CO2 Geosequestration (“CCS Ready”)
POTENTIAL ADJUNCTS:
Low Emissions Power Generation via Leveraging
Load-Following / Peak-Shaving Ability via Storage of Intermediate Liquid Products
Urea Plant Design DriversLatrobe Valley Coal is very low cost < A$1/GJ (Equates to <US$0.7/GJ vs $8-12/GJ Henry Hub gas in 2007/8)
Coal is very high moisture and potentially high sodium(Steam fluid bed drying and water quench gasification mandated)
Proximate power supply is very low cost: A$35-45 /MWh (Incentive for electric in lieu of steam compressor drives)
Fresh water supply is potentially constrained(Favours electric drives plus water conservation measures)
Milling & Drying
(RWE X3)
RAW LIGNITE
(~8000 TPD)
SIEMENS
GASIFIER
(x 2)
Air Separation
AIR
Oxygen (2200 TPD)
Slag (~100 TPD) Nitrogen
Raw Quenched Syngas CO:H2O Shift
Gas Treatment
Sulphur Recovery
H2S
Hydrogen
Ammonia Synthesis
Carbon Dioxide
Urea Production
UREA 3800 TPD
Sulphur (~20 TPD)
NH3
Carbon Dioxide(~4000 TPD to disposal)
Dried Coal
QUENCH WATER
~160 MWe EXTERNAL POWER SUPPLY
~4 MWe
15 MWe
23 MWe74 MWe
Recovered Water
13 MWe
3800 TPD UREA PLANT WITH IMPORTED POWER
~3.8 Gl/a Cooling Water
Potential Feedstocks
NWSE GDSE Moisture Ash (db) Na (db)COAL REFERENCE (MJ/kg) (MJ/kg) wt% wt% wt%
Loy Yang ROM* 8.6 26.3 60.6 2.3 0.12
Yallourn Seam (1) 6.9 25.6 65.7 3.0 0.67
Yallourn Seam (2) ** 7.0 25.4 65.3 2.3 0.53
Morwell 1A Seam (3) 6.9 26.2 66.8 1.2 0.28
* Drying & Gasification tests performed in 2005 for Monash Energy** Drying & Gasification tests performed in 2008 for Latrobe Fertilisers Ltd
MHC @ 52%RH (wb) 16days vs Na
12.0
12.5
13.0
13.5
14.0
14.5
15.0
0.00 0.10 0.20 0.30 0.40 0.50 0.60 0.70 0.80
Na % db in Coal
Moi
stur
e C
onte
nt %
LY ROM
Site 3 Site 2
Site 1
Effect of Sodium Content on Equilibrium Moisture Level
MAIN CONCLUSION FROM DRYING TEST:For same scale as RWE Niederaussem Demonstration Drier, LUP drier capacity will only be ~ 80% under similar operating conditions due to lower heat/mass transfer coefficient. This applies for all Latrobe coals. (Nominal water removal rate is only 80 TPH instead of 100 TPH expected from Niederaussem)
IMPLICATIONS for 3800 TPD Urea Plant, including extra coal for dry lignite fired boiler:
Coal Type LY ROM Y-Seam 50:50 MixMoisture 60.5% 66.5% 63.5%Raw Coal (TPD)Urea Only 7410 9650 8440Urea+Fuel 7900 11500 9400
3 Drier Utilization 75% 123% 95%
SECONDARY OBSERVATIONS:Ability to increase operating capacity through increasing
steam supply pressure is limited by fine particle carryover
Raw milling power very low cf. Rhenish lignite
Final dryness (14% 12%) governed by ambient air conditions (flow, temperature, humidity)
Recovered condensate very acceptable for water quench in gasification process
Final particle size exceeds SFGT specification limits thus requiring supplemental screening/milling upstream of gasification
PROPERTY UNIT VALUEpH ~4.0Conductivity μS/cm ~42Sodium mg/l <0.5Potassium mg/l <0.5Ammonia mg/l <0.2Chloride mg/l <1Sulphate mg/l <2Phosphorus mg/l <0.1TOC mg/l ~17Solids mg/l ~1COD Filtrated mg/l <40
Average test values for vapour condensate from Yallourn seam coal
(% dry basis)Sample
Description Ash Yield SiO2 Al2O3 Fe2O3 TiO2 K2O MgO Na2O CaO SO3 AFT (degC)
Loy Yang ROM 2.3 45.4 15.4 5.4 0.95 0.54 5.9 6.9 2.1 9.0 ~1250Site 1, Yallourn 3.2 1.1 0.9 4.5 0.03 0.4 25.5 31.5 3.1 19.1 1550+Site 2, Yallourn 2.3 2.1 4.8 2.9 0.09 0.18 20.8 32.3 4.3 18.7 1550+
Site 3, Morwell 1A 1.3 2.3 11.5 3.8 0.01 0.46 13.8 28.5 4.1 27.0 1550+
Fluxant (LYPS ash) Add 2-3% 50.0 23.3 7.2 2.3 0.8 7.5 2.9 2.0 0.6 1300-1350
Feedstock Ash Characteristics
Post Drying Test Particle Size Distribution
0.1
1
10
100
10 100 1000 10000
Screen Size (microns)
Wt%
Ret
aine
d on
Scr
een
Loesche
IBC Top
IBC Bottom
UVR-FIE AsReceivedUVR-FIE AsMilledSFGT
2008 SFGT Gasification Trials with Yallourn seam coal:7 October: Pre-Test @ 3% db flux addition
10 October Witness Test @ 3% db flux addition
15 October Witness Test @ 1.8% db flux addition
PRINCIPAL CONCLUSIONS:Taking into account the successful Monash Energy
trial in 2005 plus the most recent trials with Y-seam coal, two SFGT gasifiers will be able to supply a 3800 TPD urea plant using essentially any low-ash feedstock sourced from Loy Yang mine
Due to the need for slightly higher gasification temperatures, coupled with its somewhat lower density when dried plus lower calorific value, Y-seam coal has less operating capacity margin than LY ROM coal.
SECONDARY OBSERVATIONS:SFGT performance guarantee is contingent on meeting
moisture content less than 12% and particle size less than 500 micron
Fluidization and particle transport tests by SFGT may mitigate the need for extensive post-drying milling however some form of particle classification will still be required
Additional particle drying may be advantageous and could possibly be realized using the nitrogen transfer system from drier to gasifier
A 50:50 blend of LY-ROM and Yallourn-Seam or similar high AFT coal may overcome the need for flux addition, and consequent increase in oxygen demand
Milling & Drying
(RWE X3)
RAW LIGNITE
(~8000 TPD)
SIEMENS
GASIFIER
(x 2)
Air Separation
AIR
Oxygen
Slag Nitrogen
Raw Quenched Syngas CO:H2O Shift
Gas Treatment
Hydrogen
Ammonia Synthesis
Carbon Dioxide
Urea Production
UREA 3800 TPD
NH3
Carbon Dioxide
Dried Coal
QUENCH WATER
Recovered Water
3800 TPD UREA PLANT FRONT END TECHNOLOGIES
SFGT 500 MWth Gasifier (per Ningxia)
RWE Drier Niederaussem(100TPH water removal rate)
Implications for Process/Utility Integration:All process water demands should be met with water recovered from
coal drying unit, therefore the only water requirement is for cooling needs that cannot be economically realized by air cooling
Steam system configuration is biased towards maximizing LP steam generation to facilitate coal drying with minimal extra coal demand (< 12%) leading to advantageous application of (ejector) thermo-compressors
A considerable quantity of low grade heat is rejected from the drying unit, therefore could be utilized for BFW pre-heating, AAR (ammonia absorption refrigeration) and miscellaneous heating needs
If CPRS is legislated mechanical vapour recompression can be readily incorporated to reduce CO2 emissions
The use of excess LP nitrogen from the ASU should be considered to reduce residual moisture in the dried coal ahead of gasification
Raw Lignite Mills
Raw coal (0 - 80 mm)
Drier
Circulation Cyclone
Vapour Electrostatic Precipitator
CirculationBlower
Dry Lignite to Milling & Gasification
Condensate return
to BFW System
External steam ~4 bara (sat)
0 - 2 mm Air Cooled Condenser
Bleed to atm.
Condensate to Quench
RWE Steam Fluidized Bed Drier Without Heat Recovery
Coal Steam ~1.2 bara
~130 C
Drier
Gasifier Shift Rectisol & LIN Wash
Ammonia Synthesis
Urea Syn & Granulation
Superheater /Auxiliary
BoilerASU
MP Steam ~ 50 barg
LP Steam @ 4-5 barg
Preliminary System Lineup with Thermo-compressors (Indicative TPH Steam Flows for LY ROM coal)
~250 TPH
Water Treatment
SulphurRecovery
36 100 126#
10
801
40
130 *
*Start Up Only
** LLP Steam
# 30 barg only
(60)**85
2 10
(31)**35
3
6061
120
~185 TPH Atm Steam
Cooling Tower M/U
3.57
Steam/Condensate Return3.43
Wet Syngas to Shift Reaction
1.70
Shift Water Return to Quench1.38
Quench Water M/U
1.35
Quench Wastewater
1.20Coal Water M/U to Cooling Tower
0.27
Cooling Tower Blowdown0.13
Boiler Blowdown0.04
Boiler Chemicals
0.00
Demin Water from Loy Yang A
0.60
HQ Water
3.57
Coal Drying Unit Water
1.62
Dried Coal - Water and Salt
0.16
Cooling Towers
3.84
Quench
2.90
Evaporation3.46
Windage0.25
Boilers
4.02
Steam Losses0.55
Final Effluent
1.37
Shift Reaction
1.70
Shift Water Losses
0.32
Water Uses/Processes
Demin Water
Low TDS Water
High TDS Water
Shift Water
Steam/Condensate
WastewaterBoiler Chemicals
CONVENTIONS
Units: GL/yr Parsons Brinckerho
Indicative SANKEY Diagram for LY ROM Coal
ACKNOWLEDGEMENTSLatrobe Fertilisers Limited acknowledges the contribution of the following organizations, whose highly capable personnel have supported its efforts towards realizing the Latrobe Urea Project:RWE Power International, RE GmbH
Siemens Fuel Gasification Technology GmbH & Co. KG
GHD Pty Ltd
HRL Technology Pty Ltd
Loy Yang Power
Parsons Brinckerhoff Australia Pty Ltd
United Group Resources Limited
WorleyParsons Services Pty Ltd
Wuhuan Engineering Corporation Ltd