A large-scale carbon dioxide (CO₂) capture technology made possible through support from the Department of Energy’s Office of Fossil Energy and National Energy Technology Laboratory has captured and transported its 4-millionth metric ton of CO₂.

Air Products and Chemicals designed, built, and is operating the state-of-the-art CO₂-capture and storage system at their hydrogen-production facility located at the Valero Port Arthur Refinery in Port Arthur, Texas.

The project utilizes a gas-separation technology called vacuum swing adsorption to capture more than 90 percent of the CO₂ from the product streams of two commercial-scale steam methane reformers, preventing its release into the atmosphere.

In addition to demonstrating the integration of Air Products’ vacuum swing adsorption technology, the project is also helping to verify that CO₂-enhanced oil recovery (CO₂-EOR) is an effective method for permanently storing CO₂. CO₂-EOR allows CO₂ to be stored safely and permanently in geologic formations, while increasing oil production from fields once thought to be exhausted.

The CO₂ captured from the Port Arthur facility is being used for EOR at the West Hastings Unit oil field in southeast Texas. Injected CO₂ can dissolve and displace oil residue that is trapped in rock pores. The demonstrated technology can also enhance the U.S. hydrogen market for refinery use, which is estimated to be almost 4 million tons annually.