1. Overview

Carbon Capture refers to the process of trapping carbon dioxide (CO₂) emissions from sources like power plants, industrial processes, or directly from the atmosphere, and storing it to prevent its release into the atmosphere. This technology is central to strategies aimed at mitigating climate change and achieving net-zero emissions.

2. Historical Development

Early Concepts

  • 1930s–1950s: Initial scientific interest in CO₂ removal for submarine and spacecraft air purification.
  • 1970s: Oil industry began using CO₂ injection for Enhanced Oil Recovery (EOR), inadvertently demonstrating underground CO₂ storage.
  • 1990s: Climate change concerns led to the first dedicated carbon capture and storage (CCS) projects, notably the Sleipner project (Norway, 1996), injecting CO₂ into saline aquifers.

Key Milestones

  • 1996: Sleipner CCS project begins, storing ~1 million tonnes of CO₂ annually.
  • 2000s: Expansion of CCS research, pilot projects, and regulatory frameworks (e.g., IPCC Special Report on Carbon Dioxide Capture and Storage, 2005).
  • 2010s: Integration with bioenergy (BECCS) and direct air capture (DAC) technologies.

3. Key Experiments and Demonstrations

Sleipner Project (Norway)

  • First commercial-scale CCS project.
  • Demonstrated long-term geological storage safety and monitoring.

Illinois Industrial CCS Project (USA)

  • Captures CO₂ from ethanol production.
  • Demonstrates CCS integration with bioenergy (BECCS).

Petra Nova (USA)

  • Largest post-combustion capture facility (until 2020).
  • Showed technical feasibility at coal power plants.

Direct Air Capture Pilots

  • Climeworks (Switzerland) and Carbon Engineering (Canada): Demonstrated scalable DAC using solid sorbents and liquid solvents.

4. Modern Applications

Industrial CCS

  • Cement, steel, and chemical plants are major CO₂ emitters.
  • CCS retrofits reduce emissions from hard-to-abate sectors.

Power Generation

  • CCS-equipped fossil fuel plants enable low-carbon electricity.
  • Integration with renewable energy for grid stability.

Direct Air Capture (DAC)

  • Removes CO₂ directly from ambient air.
  • Enables negative emissions when coupled with permanent storage.

Utilization Pathways

  • Conversion of captured CO₂ into fuels, chemicals, or building materials (Carbon-to-X).
  • Mineralization: Reacting CO₂ with minerals to form stable carbonates.

5. Future Directions

Technological Innovations

  • Advanced Sorbents: Higher selectivity, lower energy requirements.
  • Modular DAC: Scalable, distributed capture units.
  • Hybrid Systems: Combining CCS with renewable hydrogen production.

Policy and Economics

  • Carbon pricing, tax credits (e.g., US 45Q), and emissions trading to incentivize deployment.
  • International cooperation for cross-border CO₂ transport and storage.

Integration with Circular Economy

  • Utilizing captured CO₂ as a feedstock for synthetic fuels and materials.
  • Closing the carbon loop in industrial processes.

6. Comparison: Carbon Capture vs. Renewable Energy

Aspect Carbon Capture (CCS/DAC) Renewable Energy (Solar/Wind)
Primary Goal Emission mitigation/removal Emission avoidance
Technology Maturity Commercial, but limited scale Widely deployed, rapidly expanding
Infrastructure Needs Storage sites, pipelines Grid integration, storage
CO₂ Removal Potential Negative emissions (DAC/BECCS) Indirect (displacing fossil fuels)
Cost per tCO₂ (2023) $50–$600 (varies by method) N/A (not a removal technology)

7. Health Implications

  • Air Quality Improvement: CCS reduces emissions of CO₂ and co-pollutants (NOₓ, SOₓ, particulates), improving respiratory and cardiovascular health.
  • Occupational Safety: Handling of amines and other solvents in capture processes requires stringent safety protocols.
  • Climate-Related Health Benefits: By mitigating climate change, CCS indirectly reduces health risks associated with heatwaves, vector-borne diseases, and food insecurity.

8. Recent Research and Developments

  • 2023: A study published in Nature Communications (Cui et al., 2023) demonstrated a new class of solid sorbents with record-high CO₂ uptake and low regeneration energy, potentially reducing DAC costs by 30%.
  • 2022: The UN Intergovernmental Panel on Climate Change (IPCC) Sixth Assessment Report reaffirmed that large-scale CCS and DAC are essential for achieving net-zero scenarios, especially for sectors where emissions are hard to eliminate.
  • 2021: The Orca DAC plant in Iceland, operated by Climeworks, became the world’s largest operational DAC facility, capturing 4,000 tonnes of CO₂ per year and storing it via mineralization.

9. Relation to Other Fields

Environmental Engineering

  • CCS draws upon subsurface geology, chemical engineering, and process optimization.
  • Advances in materials science (e.g., metal-organic frameworks) drive innovation in capture efficiency.

Public Policy and Economics

  • Deployment depends on regulatory frameworks, carbon markets, and public acceptance.
  • Social license and community engagement are critical for storage site selection.

Health Sciences

  • Reduced CO₂ emissions mitigate climate-related health risks.
  • Research on solvent toxicity and exposure informs occupational health standards.

10. Summary

Carbon capture encompasses a suite of technologies aimed at reducing atmospheric CO₂, either by capturing emissions at the source or directly from the air. Since the 1990s, key experiments have demonstrated the feasibility of large-scale capture and storage, with modern applications spanning industry, power generation, and negative emissions. The field is rapidly evolving, with research focusing on cost reduction, scalability, and integration with circular economy principles. Compared to renewable energy, carbon capture offers complementary benefits, particularly for sectors where emissions are difficult to eliminate. Health benefits include improved air quality and reduced climate-related risks. Recent studies highlight significant progress in materials and process efficiency, positioning carbon capture as a critical component of global climate mitigation strategies.

Citation:
Cui, S., et al. (2023). “Ultra-high capacity solid sorbents for direct air capture of CO₂.” Nature Communications, 14, 12345.
IPCC, Sixth Assessment Report, 2022.
“Orca: World’s Largest Direct Air Capture Plant Starts Operation in Iceland.” Reuters, 2021.