1. Chimney is a structure that provides ventilation for the hot smoke or smoke of boiler, furnace, furnace or fireplace.
 2. Chimneys are usually vertical, or as close to vertical as possible, to ensure a smooth flow of gas, sucking air into the so-called chimney combustion or chimney effect.
 3. The space inside a chimney is called a flue.
 4. Chimneys may be found in buildings, steam locomotives and ships.
 5. The height of the chimney affects its ability to transmit flue gas to the external environment through the chimney effect.
 6. In addition, the use of chimneys in high-altitude areas can reduce the impact on the surrounding environment.
 7. In the case of chemical corrosive output, the chimney high enough can allow the chemical substances in the air to partially or completely neutralize themselves before reaching the ground level.
 8. Dispersion of pollutants over a larger area can reduce their concentration and promote compliance with regulatory limits.
 9. At present, the highest chimney in the world is the chimney of GRES-2 power station in Kazakhstan, which is 420 meters high.
 10. At present, the highest chimney in China is the one of Shanxi Shentou No. 2 Power Plant, which is 270 meters high.