Abby L. Harvey
GHG Monitor
10/24/2014
Capital SkyMine, a first-of-its-kind commercial-scale carbon capture and utilization demonstration project, opened this week outside of San Antonio, Texas. The project, owned by Skyonic, pulls flue gas off of the Capital Aggregates cement plant into the new $125 million Capitol SkyMine plant, where the CO2 is mineralized to create baking soda, hydrochloric acid and bleach, which are then sold. The plant is expected to generate roughly $48 million in revenue and $28 million in annual earnings. “We are able to basically run our carbon capture system at a profit. … The natural comparison is [carbon capture and storage] where you would have a cost per ton of carbon and then you inject it underground. We’re different because we make a profit per ton of carbon and we sell the products into the market place,” Skyonic spokeswoman Stacy MacDiarmid told GHG Monitor this week. According to a Skyonic press release, the process captures up to 90 percent of carbon emissions. The project was completed on time and on budget.
The products produced by the SkyMine process are in high demand and of good quality, MacDiarmid said. “The benefits to our process and this plant is that we’re producing carbon negative chemical products and they’re pretty lucrative markets. There are lots of industrial markets for baking soda, and we’re producing a really high grade. It’s better than food grade … I’ve actually made cookies with it,” she said. “The hydrochloric acid that we make has oil field applications as well and that’s a growing market. The bleach, everybody uses bleach, it’s very common and it’s easy to sell."
Once the carbon has been captured from the flue gas, it is transferred back to the cement plant next door and emitted. This gives the process an advantage over other carbon utilization processes, such as enhanced oil recovery, because transportation costs are minimal. “The products that we make are used everywhere, and are easily transportable and there’s a really low penalty for getting our products to market. I think one of the things that you see with CO2 as your product is that you have to build pipes to get it where you need it and that is very expensive,” MacDiarmid said.
The SkyMine technology has also proven very adaptable, MacDiarmid said. “We had a couple of mobile pilot plants that we did in 2007-2008 at different plants in Texas and those were coal fired power plants, so a little bit different than a cement plant, but still coal, but they were using radically different kinds of coal. One of the things that we learned by doing those projects is that our process is really indifferent to the concentration of CO2 in the flue stream. That means that we can do our process on a natural gas plant, that’s fine, even though there’s less CO2 in the stream, we don’t have to pre-treat that stream to try and concentrate the CO2 before we can get it out. We just operate as normal and we still get our CO2.”
Project Funded, in Part, by DOE
The project received some funding from the Department of Energy including $28 million in grants awarded under the American Reinvestment and Recovery Act. "The DOE grants really served as a really good vote of confidence because clearly everybody knows that the Department of Energy does their due diligence," MacDiarmid said. “Today’s announcement demonstrates the range and potential for carbon capture technologies,” said Energy Secretary Ernest Moniz in a DOE release this week. "Through this partnership, the Department has shown its commitment to finding innovative uses for carbon that can have a positive impact on the economy while also reducing carbon emissions."
New Technologies to Come
Skyonic is also in the process of developing different carbon capture and utilization technologies. A pilot plant for the company’s SkyCycle technology is currently being planned in Canada. The SkyCycle technology will have outputs including hydrochloric acid and limestone. Skyonic has also received $500,000 CAD (roughly $460,660 USD) from the Climate Change and Emissions Management Corporation (CCEMC), an Alberta-based non-profit, to support research and development of the SkyCycle pilot plant. According to a May Skyonic release, “while current industry estimates place the cost of carbon capture between $150 and $450 per ton, SkyCycle uses a thermolytic chemical reaction to capture carbon dioxide emissions at costs estimated to be between $16 and $25 per ton, significantly lower than industry averages.”
