👉 Smokestacks are structures that are used in various industries, especially those involving the production of coal and other fossil fuels. These stacks are typically used to store and transport heavy fuel gases such as sulfur dioxide (SO2), nitrogen oxides (NOx), and particulate matter (PM) from burning coal or other fossil fuels. The primary purpose of smokestacks is to capture and remove these pollutants before they reach the atmosphere, thereby reducing air pollution. Smokestacks can be constructed using various