SCR in coal-fired power plants is used to reduce nitrogen oxide emissions. It works much like an automobile’s catalytic converter which also is used to reduce emissions produced by the car’s internal combustion engine.
Prior to exhaust exiting the car’s tailpipe, it passes through the catalytic converter, where a chemical reaction for reducing emissions takes place.
Similarly, at a power plant, nitrogen oxides emissions pass through an industrial version of a catalytic converter known as SCR and reacts with ammonia, converting it to elemental nitrogen and water.
