Heirloom Carbon Technologies

Heirloom Carbon Technologies develops direct air capture (DAC) technology intended to remove carbon dioxide from the atmosphere and store it durably. The company’s approach combines carbon mineralization with direct air capture, using limestone—an abundant mineral—as the material that absorbs CO₂. Heirloom describes its mission as restoring balance to the atmosphere by accelerating a natural process that ordinarily takes years into a cycle of days.

In Heirloom’s process, limestone is heated in a renewable-energy-powered kiln to release a concentrated stream of CO₂. The remaining material is hydrated with water and prepared on vertically stacked trays, where it absorbs CO₂ from ambient air. The company says its technology accelerates this uptake to less than three days, after which the mineral material is cycled through the process again. Reuse is intended to reduce the amount of limestone required, while modular facility designs are intended to support expansion.

Captured CO₂ can be permanently stored underground or incorporated into concrete. At the company’s Tracy, California, facility, Heirloom has worked with CarbonCure to embed captured atmospheric CO₂ in concrete used in building foundations. The company also sells carbon removals to customers; its website describes credits as representing one ton of permanently removed CO₂ and says removal is independently monitored by a third party. Its customers therefore include organizations purchasing carbon-removal credits, while its storage and concrete applications involve project and technology partners.

Heirloom reports that its first commercial DAC facility is operating in California and fulfilling customer carbon-removal purchases. The company is also developing two facilities in northwestern Louisiana, which it says are planned to have a combined annual capture capacity of nearly 320,000 tons. Heirloom states that its facilities are powered by additional renewable energy and that its projects are being developed with labor protections and community governance considerations.

The company was established in 2020 as Heirloom Carbon Technologies, Inc. Its public materials frame its work around building a scalable, lower-cost approach to durable carbon removal, using engineering to accelerate mineral processes. The stated long-term ambition on its technology page is to help remove one billion tons of CO₂ from the atmosphere by 2035. These are company goals and descriptions rather than a guarantee of future performance.

Heirloom presents community benefits as part of its approach to deployment, describing potential local employment, investment, and stakeholder input alongside climate benefits. Its careers page says it seeks people committed to addressing climate change. The company’s published materials also emphasize learning from operational data to improve CO₂ uptake and lower costs as its facilities scale. Its work spans climate technology, industrial facility development, carbon accounting and monitoring, and coordination with carbon storage and concrete partners.