布鲁金斯学会-重工业脱碳的挑战（英文）-2021.6-31页_897kb

Summary of "The Challenge of Decarbonizing Heavy Industry"

Core Content

Heavy industry is essential for modern life, providing critical materials like steel, cement, and chemicals. However, it is also a major source of greenhouse gas (GHG) emissions, responsible for nearly 40% of global CO₂ emissions when indirect emissions are included. These industries are among the most difficult to decarbonize due to technical, economic, and trade-related challenges.

Main Industries and Their Emissions

1. Steelmaking

• Emissions: Steelmaking accounts for about 8% of global energy use and is responsible for a significant portion of industrial CO₂ emissions.
• Process: Steel is produced by converting iron ore to pig iron in a blast furnace using coke (a carbon-based reducing agent) and then further processing in a basic oxygen furnace.
• Emissions Sources: CO₂ is emitted both from fuel combustion and chemical reactions.
• Decarbonization Options:
  • Recycling: Steel can be recycled with 74% less energy and no process emissions. However, global demand for steel exceeds the supply of recyclable material.
  • Hydrogen Direct Reduction: Replacing carbon with hydrogen as a reducing agent can eliminate CO₂ emissions. This process is still in early development and may be more expensive than traditional methods.
  • Biocarbon: Using biomass-derived charcoal as a reducing agent can reduce emissions by around 20%, though it faces competition with fossil fuels.
• Challenges: High capital intensity, long asset life, and low profit margins make investment in new technologies difficult.

2. Cement Production

• Emissions: Cement production is the second-largest industrial emitter of GHG, with 60% of emissions coming from the chemical process of producing clinker.
• Process: Limestone is heated in a kiln to produce calcium oxide (clinker), which is then ground into cement.
• Decarbonization Options:
  • CCUS (Carbon Capture, Utilization, and Storage): Capturing CO₂ from clinker production is a key method. Examples include Anhui Conch and Heidelberg Cement.
  • Clinker Substitution: Using alternative materials like fly ash, slag, or natural substances can reduce emissions. However, this is limited by quality and supply concerns.
• Challenges: High process heat requirements, limited alternatives to fossil fuels, and the need for significant investment in CCUS.

3. Chemical Industry

• Emissions: The chemical industry is responsible for about 70% of industrial CO₂ emissions and uses large amounts of fossil fuels as both feedstocks and energy sources.
• Key Products: Methanol, olefins, aromatics, and ammonia are central to the chemical industry and account for more than two-thirds of energy use.
• Decarbonization Options:
  • Process Electrification: Using renewable electricity for certain processes can reduce emissions.
  • Zero-Carbon Hydrogen: Hydrogen can replace fossil fuels in chemical reactions, reducing CO₂ emissions.
  • Feedstock Alternatives: Using biomass, waste, or CO₂ from other industrial processes can lower emissions.
• Challenges: High energy consumption, diverse processes, and reliance on fossil fuels as feedstocks.

Common Technical Challenges

• High Heat Requirements: Many industrial processes require temperatures above 1000°C, which are difficult to achieve without fossil fuels.
• Process Emissions: CO₂ is produced as part of chemical reactions, not just from combustion.
• Hydrogen Use: Hydrogen is a potential alternative to fossil fuels in some processes, but its production and use require significant infrastructure and energy.

Economic and Trade Considerations

• Low Profit Margins: Steel, cement, and bulk chemicals are capital-intensive and have minimal product differentiation, making them difficult to decarbonize without government support.
• Capital Intensity and Long Asset Life: Production facilities can last up to 50 years, locking in emissions over time.
• Trade Exposure: These industries are highly traded globally, leading to the risk of carbon leakage — shifting production to countries with lower emissions regulations.
• Policy Role: Governments must support decarbonization through subsidies, demand pull for low-carbon products, and trade policies to protect domestic industries.

Key Findings

• Steel: Can be recycled or produced with hydrogen or biocarbon, but demand for virgin steel remains high.
• Cement: CCUS and clinker substitution are promising, but the industry is cautious due to performance and quality concerns.
• Chemicals: Diverse processes and feedstock requirements make decarbonization complex, but alternatives like hydrogen and waste-based feedstocks offer opportunities.
• Global Trends: China is the largest producer of steel and cement, contributing over 50% of global production, while the chemical industry contributes nearly 40% of global revenue.
• Future Outlook: Process electrification, hydrogen-based technologies, and CCUS are key to decarbonizing these sectors, but they require significant investment and policy support.

Conclusion

Decarbonizing heavy industry is a critical step in achieving global net-zero goals. While technical solutions like CCUS and hydrogen-based processes are available, they face economic and trade-related barriers. Government policies will play a vital role in enabling the transition by reducing costs, creating demand for low-carbon products, and preventing carbon leakage.