Why are some industrial chimneys so high, like what’s the difference if it’s 150 or 300 meters?

Question

Why are some industrial chimneys so high, like what’s the difference if it’s 150 or 300 meters?

In: Engineering

Answer 1

One, A chimney is a “zero-energy” vaccum cleaner.

Two, The more smoke you create, the higher suction you need. The sides are keeping it in and the height provides a pressure differential. The higher you go, lesser is the air pressure around compared to ground.

Three, Some pollutants require to be let off higher up. It gives more time for sulphur and nitrogen compounds to burn up.