Gasification Technology for Brown Coal Power Generation

1
Gasification Technology for Brown Coal Power
Generation

• Terry Johnson
• HRL Developments Pty Ltd

APP Brown Coal Best Practice Workshop Melbourne,
June 2008
2
Issues for Brown Coal Power

• Brown coal in Latrobe Valley
• Large resource (gt100,000 Mt)
• Low level of impurities (ash lt4, sulphur lt0.5)
• Low cost (lt0.60 per GJ)
• Low emissions of pollutants (NOx, SOx, trace
  elements)
• BUT
• High moisture content (60), leads to
• Low efficiency, down by 20 c.f. black coal
• High CO2 emissions, up by 20 c.f. black coal
• Hence need for new lower CO2 emissions
  technologies such as gasification combined cycle

3
Current Latrobe Valley Steam Cycle Technology
Energy used to evaporate coal moisture is lost as
steam in the flue gas ? chimney.
4
Efficiency Improvement - Drying
Efficient coal pre-drying - reduced moisture
gives higher efficiency and lower CO2
5
Types of Coal Gasifiers

• Fluidised bed suitable for high reactivity coals
  - operates at low temperature (800-900 degC), dry
  ash removal, can be air blown
• Entrained flow suitable for lower reactivity
  coals - operates at high temperature, molten ash
  removal, usually O2 blown

6
IDGCC Future for Brown Coal

• IDGCC is a technology that supports the future of
  brown coal in a carbon-constrained world
• Increased efficiency and 30 lower CO2 emissions
  than current best Latrobe Valley
• Lower cost of electricity production
• Lower water consumption, 50 of steam cycle plant
• Potential for v. low CO2 emissions using CCS, at
  lower cost than other technologies

7
IDGCC Technology

• Integrated Drying Gasification Combined Cycle
  (IDGCC)
• Coal is dried using direct contact with hot gas
• Dried coal is converted to hot combustible gas in
  a fluidised bed gasifier
• Hot gas is cooled by the coal drying step
• Gas is cleaned, burned in a gas turbine producing
  power
• Hot exhaust gas from gas turbine used in boiler
  to produce steam
• Steam used in a steam turbine to produce extra
  power
• Gas turbine plus steam turbine - combined cycle

8
IDGCC Process
9
Development of IDGCC Technology
TGA (1990)
CGDU (1992)
CGDF (1996)
Dry coal gasification, gas flared
Wet coal gasification and power generation
Reactivity tests
10
IDGCC Proven at 10-MW Scale

• Wet coal drying, gasification and power
  generation
• Power sent to grid
• 10-MW scale

11
Advantages of IDGCC Technology

• Particularly suited to reactive, wet coals
• Cost reductions of around 30 on boiler
  technology, wet coals
• Efficiency at around 40 HHV (from gas
  turbine/steam turbine) compared with 33 for
  supercritical boiler plant
• Significant reduction in CO2 emissions around 30
  compared with current best Latrobe Valley boiler
  plant
• Savings on water - IDGCC uses only 50 of usual
  cooling water levels of boiler plant
• Suitable for pre-combustion CO2 capture for lower
  CO2 emissions in future

12
CO2 Emissions
13
Water Consumption
14
Costs including CO2 Capture
15
IDGCC Next Steps
500 MW IDGCC Demonstration Project 2 gasifiers
supplying Gas Turbine Combined Cycle Proposed
location Latrobe Valley

16
500 MW IDGCC Demonstration Project Structure

• Funding will be a mix of equity, debt and
  government support
• State Government grant (50M) announced November
  2006
• Federal Government grant (100M) announced March
  2007
• HRL and Harbin Group in Joint Venture
• Harbin to be EPC Contractor
• Will engage local constructor for site erection
• Planned start of operation early 2012

17
500 MW Project Outcomes

• Provide 500 MW combined cycle power into Grid
• Demonstrate 500 MW IDGCC power at Greenhouse
  Intensity of about 0.8 tCO2/MWh
• Confirm low fuel use, low water consumption
  compared to current LV power plant
• Prove scale up for commercial operation of IDGCC
• Provide the platform for commercial deployment of
  low greenhouse power at cost of about 39/MWh

18
CO2 Capture

• IDGCC is suitable for pre-combustion CO2 capture
  with systems already used commercially in other
  industries
• Additional cost is high 45 increase in capex
• Penalty on power output 10
• Cost of CO2 capture lower for IDGCC than other
  power technologies
• Working with CO2CRC to evaluate improved solvent
  systems more suited to IDGCC, with support from
  Victorian ETIS program
• HRLs aim is to move towards near-zero CO2 from
  IDGCC in future with CCS (believe we can get CO2
  emissions down close to 0.2 t/MWh)