The technology used to clean coal during combustion is called "clean coal technology" or CCT. There are
several methods used in CCT, including:
1. Flue gas desulfurization (FGD): This method removes sulfur dioxide (SO2) from the flue gas by using a
scrubber. The scrubber contains a solution of calcium oxide or calcium carbonate, which reacts with the
SO2 to form calcium sulfate or calcium carbonate.
2. Low NOx burners: These burners reduce the amount of nitrogen oxides (NOx) emitted during
combustion by controlling the amount of oxygen and fuel that is supplied to the burner.
3. Electrostatic precipitators (ESP): These devices remove particulate matter (PM) from the flue gas by
using an electrostatic charge to attract the particles to a collection plate.
4. Gasification: This process converts coal into a gas, which can then be burned more efficiently and
cleanly.
5. Integrated Gasification Combined Cycle (IGCC): This technology combines gasification with a
combined cycle power plant, which can achieve efficiencies of up to 50%.
Overall, the goal of CCT is to reduce emissions of pollutants such as SO2, NOx, and PM, while also
increasing the efficiency of coal-fired power plants.