It’s very important for all of us to do what we can to keep the environment healthy. Whether this means recycling, carpooling, or not littering, there is something each of us can do to make the Earth a nice place to live for us and for future generations.
Coal companies have a responsibility to keep the environment clean, too. How are they doing that? One way is through clean coal technology (CCT). CCT is actually a group of methods that coal power plants can use. They all do different things, but have a common goal: to make coal cleaner!
Flue Gas Desulfurization is also called “scrubbers.” You can remember this by thinking of how you scrub your hands when you wash them, to get them clean. Desulfurization does just what it sounds like: it takes the sulfur out of the air when coal is combusted. It does that by adding limestone to the power plant. When the limestone meets the sulfur, the sulfur goes away.
Fluidized Bed Combustion (FBC) is another process that can sometimes use limestone. When coal is combusted in an FBC boiler, the very small pieces of coal are suspended in the air by strong currents. The coal stays in the boiler for a much longer amount of time than regular boilers. This means that the coal is combusted more completely, which makes it cleaner. FBC boilers also use a lower temperature than regular boilers, which also helps keep it clean. Limestone can be added to the boiler to make the coal even cleaner.
Carbon Capture and Storage (CCS) is used to keep carbon dioxide out of the air. When coal is combusted, carbon dioxide is produced. CCS captures that carbon dioxide and sends it through pipes. Those pipes lead underground or under the ocean. The carbon dioxide can be stored underground for a long time and won’t come back up to the surface. It eventually dissolves from being under so much pressure.
Gasification is when coal is blasted with very hot steam and turns into a gas. When the coal gets hit by the steam, it starts to break apart. The bad parts, like sulfur and nitrogen, can then be separated from the good parts. This new coal gas is like natural gas, and it can be used to make electricity.
These are just a few of the many clean coal technologies available. Different power plants use different technologies, and new power plants that are being built today are much cleaner than plants built 30 years ago. Scientists are always working on new and better ways to keep coal clean. Cleaner coal means a cleaner environment for all of us.
Be sure to see our accompanying lesson: Keep It Clean: Clean Coal Technology