20111031-IEA-Power_Generation_from_Coal_2011_56页_5mb

报告摘要

Summary of "Power Generation from Coal: Ongoing Developments and Outlook"

Core Content

This document, published by the International Energy Agency (IEA) in 2011, provides an overview of ongoing developments and future outlook for coal-based power generation technologies. It emphasizes the need for improving efficiency and reducing environmental impact, especially in the context of carbon capture and storage (CCS) and climate change mitigation.

Main Objectives

To review major ongoing developments in process technology, equipment, instrumentation, and control for coal-fired power generation.
To highlight key research and development (R&D) requirements for these technologies.
To identify barriers to the widespread adoption and deployment of advanced coal technologies.
To provide recommendations for policy and technology development to support a more sustainable and efficient coal power sector.

Key Recommendations

Introduce policies to reduce the construction of sub-critical coal plants for new builds.
Use the successful Lagisza CFBC plant in Poland as a model for future supercritical CFBC projects.
Maximize plant efficiency when applying CCS, as this is essential for reducing the energy penalty associated with CO₂ capture.
Reduce the energy penalty of CO₂ capture through innovative systems such as membrane reformer reactors.
Promote the development of low-grade coal drying and beneficiation technologies to improve efficiency and reduce emissions.

Main Technologies and Developments

1. Supercritical and Ultra-supercritical (USC) Pulverised Coal (PC) Technology

The Supercritical Cycle: Supercritical technology operates at high steam pressures (25 MPa or more) and temperatures (600°C to 620°C), resulting in a single-phase fluid and higher efficiency than sub-critical plants.
Current Commercial Status: Super- and ultra-supercritical units are available in many countries, including Australia, Canada, China, Germany, India, South Africa, and the United States.
Efficiency Gains: USC plants can achieve efficiencies of up to 46% (LHV, net), significantly higher than sub-critical units (38%–39%).
Unit Capacity: Some USC plants can reach up to 1100 MWe.
Future Potential: With ongoing materials development, efficiencies of up to 50% (LHV, net) may be achievable within 10–15 years.
Barriers: High capital costs, limited experience with high-temperature and high-pressure systems, and challenges in retrofitting existing sub-critical plants with CCS.
Cost Implications: USC plants have higher boiler and turbine costs (40%–50%) but lower balance-of-plant costs (13%–16%), leading to a total investment cost 12%–15% higher than sub-critical plants.

2. Circulating Fluidised Bed Combustion (CFBC) Technology

Advantages: Better utilisation of low-rank fuels, lower emissions of conventional pollutants.
Recent Developments: The first supercritical CFBC plant (460 MWe) was commissioned in Poland in 2009.
Future Prospects: China and Russia have programmes to construct supercritical CFBC units.
Barriers: Limited commercial experience, technical challenges in scaling up, and need for supportive policies.

3. Integrated Gasification Combined Cycle (IGCC) Technology

Status: Only six coal-based IGCC units exist globally.
Potential: IGCC has the technical capability to capture CO₂ efficiently.
Challenges: High costs and long construction times, lack of clear emission guidelines and government incentives.
Retrofit Considerations: IGCC plants may be more suitable for CO₂ capture than PC or CFBC plants.
Efficiency: IGCC can achieve efficiencies above 40% (LHV, net) with supercritical steam conditions.
Future Outlook: A few new IGCC projects are in planning or construction, but widespread deployment is not yet feasible.

4. Coal Treatment Technologies

Coal Beneficiation: Reduces ash and sulphur content, but lacks sufficient pricing incentives and R&D support.
Coal Drying: Reduces moisture content in coal, which can improve plant efficiency by up to 4–9 percentage-points.
Technologies: Steam fluidised-bed drying and mechanical thermal expression (MTE) are being developed.
Progress: Efforts are ongoing in Australia, Germany, and the United States.
Need for Demonstration: Accelerating large-scale integrated demonstration of these technologies is crucial for their wider adoption.

CO₂ Capture and Storage (CCS)

Energy Penalty: Retrofitting existing PC or CFBC plants with CCS can result in efficiency losses of up to 10 percentage-points.
CCS Readiness: Only plants with high baseline efficiency (e.g., 40% or more) are likely to be retrofittable.
Retrofit Feasibility: Less than 10% of current coal-fired capacity is considered suitable for CCS retrofit.
Future Potential: New plants using SC or USC technology are more likely to be suitable for CCS retrofit, with up to 30% of the fleet potentially retrofittable by 2030.
Operability Considerations: Plants retrofitted for CCS must be assessed for dynamic performance during start-up, shut-down, and load changes.

Outlook for Development

Efficiency Improvements: Ongoing developments in steam turbine technology and combustion systems are expected to enhance plant efficiency.
Technology Adoption: SC and USC PC plants dominate new plant orders, with a growing number of projects in China, India, and other countries.
Market Penetration: IGCC may only achieve large-scale market penetration where co-production of power and chemicals is economically viable.
Policy and Collaboration: Clear emission guidelines, government incentives, and collaboration among technology vendors and utilities are necessary for the wider deployment of IGCC and CCS.

Conclusion

The report highlights the importance of improving the efficiency of coal-fired power plants through advanced technologies such as SC and USC.
It stresses the need for supportive policies and R&D to enable the transition to cleaner and more efficient coal technologies.
CCS is seen as essential for deep emission reductions, but its deployment is constrained by high costs and technical challenges.
The successful implementation of coal drying and beneficiation technologies can significantly enhance the viability of low-rank coals in power generation.

Key Information

Global Coal Reserves: Nearly 1000 billion tonnes.
CO₂ Emissions: Coal contributes over 40% of global anthropogenic CO₂ emissions.
Efficiency Impact: A 1% improvement in efficiency can lead to a 3% reduction in CO₂ emissions.
Market Share: SC and USC plants account for 25% of global coal-fired capacity as of 2009.
Future Projections: By 2030, up to 30% of the coal-fired fleet may be retrofittable for CO₂ capture.

References and Appendices

The report includes detailed lists of figures, tables, and boxes to support its analysis.
It references the IEA's role in promoting energy security and sustainable energy policies.
The European Commission is also involved in the work of the IEA on fossil fuels.