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Capitol Aggregates Breaks Ground on CO2 Technology


Capitol Aggregates and Skyonic hosted a groundbreaking event for the installation of CO2 capture technology at Capitol’s cement mill in San Antonio. Once fully operational in 2014, the plant, which is the first of its kind in the United States, is expected to capture 300,000 tons of CO2 annually through the direct capture of 75,000 tons and additional 225,000 tons that will be offset by the production of green products. The plant is expected to turn a profit within three years from the sale of the products including sodium bicarbonate, HCl and bleach.

Greg Hale, president of Capitol Aggregates, spoke at the event, as well as Joe Jones, founder and CEO of Skyonic. Other speakers included Bexar County Judge Nelson Wolff.

“The beginning of construction is a major milestone on the road to commercialization,” said Hale. “When Skyonic began operating its demonstration plant at Capitol Aggregates several years ago, we were excited about the prospect of producing more sustainable cement. Now that the project has reached a commercial-scale, we couldn’t be happier to have such a revolutionary process at our cement factory.”

Skyonic has operated a demonstration-scale plant at the Capitol Aggregates site since 2010, with on-going support from the San Antonio community. The commercial-scale Capitol SkyMine plant will employ roughly 35 people and is expected to create more than 200 jobs through the plant's construction and on-going operations.

“I applaud the Zachry Corporation and Skyonic for setting the standard with the first commercial carbon capture plant of its kind,” Mayor Julian Castro said. “This project is another example of how San Antonio is becoming a leader in combining green technology and job creation.”

Skyonic’s electrolytic carbon capture technology, SkyMine, will selectively capture CO2, acid gases and heavy metals from the flue gas of the Capitol Aggregates plant, where the Capitol SkyMine plant will be retrofitted. The captured pollutants will be mineralized into products, including sodium bicarbonate, which are stored, transported and sold as safe, stable solids, eliminating many of the costs and concerns associated with other forms of carbon capture.

The sodium bicarbonate, as well as the hydrochloric acid and bleach that is also produced, can be sold at a profit. By producing valuable products using low-cost chemical inputs and operating at energy-efficient conditions, SkyMine captures CO2 at a substantially lower operating cost than other carbon capture technologies and allows industrial emitters to turn a profit from reduced emissions.

“Industrial manufacturing is a cornerstone of the global economy and we’re doing our part to making the process more lucrative for industries and cleaner for the environment,” said Jones. “Our partners and investors have played an important role in getting to this commercialization stage, and we’re all looking forward to starting construction and making our first plant a stand-out success.”