What pollution control measure effectively reduces nitrogen oxide emissions from coal combustion?

Lowering coal burning temperatures is an effective pollution control measure for reducing nitrogen oxide emissions from coal combustion. This is because nitrogen oxides (NOx) are formed when nitrogen in the air reacts with oxygen at high temperatures typically found in combustion processes. By reducing the combustion temperature, the reaction rate for the formation of NOx decreases, thereby lowering the overall emissions produced during the coal combustion process.

Switching to renewable energy sources would significantly reduce NOx emissions overall but does not specifically address the combustion process itself. Increasing ventilation systems pertains more to improving air quality and may not directly impact the combustion process where NOx is produced. Implementing stricter vehicle emission standards focuses on reducing emissions from vehicles rather than from coal combustion processes. Therefore, lowering coal burning temperatures specifically targets the reduction of nitrogen oxides effectively during coal burning.