Pillar to Post: Peter Welander's Blog
News and comment from Control Engineering process industries editor, Peter Welander
Cement producers and the EPA
August 11, 2010
You may have noticed recent announcements that cement producers will soon have to restrict emissions of mercury and other pollutants. New EPA regulations require that by 2013, cement producers collectively will reduce mercury and particulates by 92%, acid gasses by 97%, and sulfur dioxide by 78%.
This has a familiar ring to it, and it took me back to an earlier life where I paid a lot of attention to the cement industry. I worked for a company that manufactures spray nozzles that are used to cool flue gasses. If the gas coming out of your process is hotter than you want it to be, and there is no practical way to capture and reuse the heat, you can cool it by spraying in finely atomized water. The concept is simple but doing it effectively is harder than you might think.
Back in 1999, I presented a paper at the Cement Conference on EPA regulations that were coming into effect in 2000. One of rep organizations that sells the equipment still hosts the paper if you’re interested. Back then the EPA was concerned more with toxic gas formation (dioxins and furans) but it also wanted to restrict particulates and mercury for hazardous waste burning kilns. The point then and now is that proven and practical technologies exist to manage these emissions. SOx, NOx, mercury, acid gasses, toxic gasses, and heavy metals can all be controlled. (Carbon dioxide is another matter. A cement or lime kiln produces carbon dioxide because it’s part of the calcining process, regardless of the fuel used.)
Some plants may not want to add control technologies it because it will add cost. For better or worse, the cement industry managed to stay under the environmental radar for a long time, but regulations are beginning to catch up. Now as it implements new controls, production will shift around. Plants that can work with the new regulations without much trouble will benefit. Others will likely close and the balance of imports vs. domestic production may change. This isn’t the first industry to have to face such a displacement, nor will it be the last. Life will go on.