What does high volatile matter in coal indicate about its burning characteristics?

High volatile matter in coal indicates that it ignites easier due to the presence of a significant amount of volatile compounds. These volatile substances include gases such as methane, hydrogen, and other light hydrocarbons that are released when coal is heated. This release of gas makes the ignition process much more efficient compared to coal with lower volatile matter.

When coal has high volatile matter, it can easily catch fire and sustain burning, thus enhancing its combustibility. This characteristic is particularly beneficial in various combustion applications, as it allows for a quicker and more complete ignition, ultimately leading to a more efficient burning process.

In contrast, other characteristics of coal are not directly related to high volatile matter. For instance, burning characteristics such as burning time and the amount of ash produced depend more on the type of coal and its overall composition rather than just the volatile content. Furthermore, coal with high volatile matter typically does not mean it has less energy per weight; instead, it can have varying calorific values depending on the specific coal type.