1. Definition

Carbon Capture refers to a set of technologies and processes designed to remove carbon dioxide (CO₂) from the atmosphere or prevent its release from industrial sources. The goal is to mitigate climate change by reducing greenhouse gas concentrations.

2. Historical Context

  • 1970s–1980s: Initial research into CO₂ removal began with enhanced oil recovery (EOR) projects, using captured CO₂ to boost oil extraction.
  • 1996: Sleipner gas field in Norway became the first commercial-scale project to inject CO₂ underground.
  • 2000s: Global interest increased as climate change became a central scientific and policy issue.
  • 2010s–Present: Advances in direct air capture, bioenergy with carbon capture and storage (BECCS), and mineralization.

3. How Carbon Capture Works

A. Point-Source Capture

Captures CO₂ directly from emission sources (e.g., power plants, cement factories).

Steps:

  1. Capture: CO₂ is separated from other gases using solvents, membranes, or adsorption.
  2. Compression: CO₂ is compressed into a liquid or supercritical state.
  3. Transport: Pipelines or ships move CO₂ to storage sites.
  4. Storage: Injected underground into geological formations (e.g., saline aquifers, depleted oil fields).

B. Direct Air Capture (DAC)

Removes CO₂ directly from ambient air using chemical processes.

Process:

  • Air passes through filters containing sorbents or solvents.
  • CO₂ is extracted and concentrated for storage or utilization.

C. Bioenergy with Carbon Capture and Storage (BECCS)

Combines biomass energy production with CO₂ capture, resulting in net negative emissions.

4. Diagrams

Carbon Capture Process

Carbon Capture Process

Direct Air Capture

Direct Air Capture

5. Surprising Facts

  1. Natural Carbon Sinks Limitations: Earth’s natural carbon sinks (forests, oceans) absorb only about half of annual human CO₂ emissions; the rest accumulates in the atmosphere.
  2. Mineralization Potential: Some rocks (e.g., basalt) can permanently lock away CO₂ through mineralization, potentially storing billions of tons.
  3. Negative Emissions: BECCS and DAC can remove more CO₂ than they emit, offering a pathway to reverse historical emissions.

6. Latest Discoveries

  • Solid Sorbents: Recent advances in metal-organic frameworks (MOFs) have increased the efficiency and selectivity of CO₂ capture (Science, 2022).
  • Ocean-Based Capture: Research into ocean alkalinity enhancement shows promise for large-scale CO₂ removal (Nature Communications, 2023).
  • Modular DAC Plants: Companies like Climeworks and Carbon Engineering have built modular DAC facilities, scaling up removal capacity.

Citation:
“Direct air capture of CO₂ with chemicals: A review of commercial technologies,” Joule, 2021.
Link to study

7. Applications & Utilization

  • Enhanced Oil Recovery (EOR): Injecting captured CO₂ into oil fields to increase extraction.
  • Synthetic Fuels: Using captured CO₂ to produce methanol, jet fuel, or plastics.
  • Building Materials: Mineralized CO₂ can be used in concrete, reducing its carbon footprint.

8. Career Paths

  • Chemical Engineer: Design and optimize capture processes.
  • Geologist: Assess and monitor underground storage sites.
  • Environmental Scientist: Evaluate impacts and sustainability.
  • Data Analyst: Model carbon flows and project effectiveness.
  • Policy Advisor: Develop regulations and incentives for deployment.

9. Challenges

  • Cost: Current capture technologies are expensive ($50–$600 per ton of CO₂).
  • Scale: Billions of tons must be captured annually to meet climate goals.
  • Public Acceptance: Concerns over safety and long-term storage integrity.
  • Energy Use: Capture and compression require significant energy input.

10. The First Exoplanet Connection

The discovery of the first exoplanet in 1992 broadened our understanding of planetary atmospheres and habitability. Studying exoplanet atmospheres (e.g., CO₂ levels) informs climate science and the importance of carbon management on Earth.

11. References

  • “Direct air capture of CO₂ with chemicals: A review of commercial technologies,” Joule, 2021.
  • “Ocean alkalinity enhancement: a promising carbon dioxide removal strategy,” Nature Communications, 2023.
  • International Energy Agency (IEA) Carbon Capture, Utilization and Storage Reports, 2022.

12. Summary Table

Technology Source Storage Method Negative Emissions Latest Development
Point-Source CCS Factories Underground No Cheaper solvents
Direct Air Capture Atmosphere Underground/Util. Yes Modular plants
BECCS Biomass Underground Yes Large-scale pilots

13. Future Outlook

  • Scaling Up: Global deployment required to meet Paris Agreement targets.
  • Policy Support: Carbon pricing, credits, and investment in R&D.
  • Interdisciplinary Collaboration: Engineers, scientists, and policymakers must work together.

14. Additional Resources

End of Study Notes