Skyonic's capture-and-sequester approach goes something like this:
- Direct a power plant's polluting flue gasses into the SkyMine device
- Pull out the CO2
- Initiate a chemical reaction that turns the CO2 into harmless baking soda, hydrogen and chlorine
- Sell the byproducts on the open market
It's a very cool concept, even in its simplest form. If we look deeper, it gets even more interesting. A coal-burning power plant essentially produces three things: power (good), pollutants (bad) and heat (neutral). SkyMine uses everything we don't want or don't care about -- pollutants, waste and heat -- to create products people actually want.
The SkyMine device, which is the size of two 50-foot trailers in its prototype form, taps into the plant's flue. It directs the emissions into the trailers instead of into the air. The heat that flows out through the power plant's flue (sort of like a chimney) powers SkyMine. Burning coal produces enormous amounts of heat, so there's plenty of power to run the system. Once inside SkyMine, a series of steps changes pollutants into beneficial substances.
- SkyMine converts heat into energy that will move the gases through the system. In that first heat-conversion step, toxic chemicals like mercury, SO2 and NOx (sulfur dioxide and nitrogen oxide, acid rain gases that lead to smog) separate from the flue gas. SkyMine stores these harmful chemicals on-site for later disposal. What's left is primarily CO2.
- The CO2 enters a series of absorption chambers. Once inside, SkyMine injects sodium hydroxide (NaCl and H2O, also known as salt and water) into the chambers. A chemical reaction takes place: CO2 + H2O + NaCl > NaHCO3 + H2 + Cl2 (carbon dioxide + water + salt > sodium bicarbonate + hydrogen gas + chlorine gas)
- The sodium bicarbonate, or baking soda, is in solid (crystalline) form, and the absorption chambers dump it into a storage area. The hydrogen and chlorine gasses are stored separately from the baking soda. SkyMine then returns the remaining, mostly harmless flue gasses to the power plant, where the power plant releases them into the atmosphere.
This process is very effective: SkyMine removes between 85 percent and 97 percent of the mercury, acid rain gasses and CO2 from the flue gases that pass through the system. The reaction's main byproduct, sodium bicarbonate, is perfectly harmless and endlessly useful. But here's the thing: Even with the thousands of home and industrial uses for baking soda, there may not be enough buyers in the entire world for the amount of baking soda SkyMine would produce.
So how much baking soda are we talking about, and where's it going to go? Next, we'll look at the ups and downs of SkyMine.