烟煤, also known as bituminous coal, is a type of coal that is characterized by its high carbon content and energy density. It is commonly used as a fuel source for electricity generation and in industrial processes. The carbon content in 烟煤 typically ranges from 45% to 86%, making it an efficient energy source. This type of coal is formed from the remains of ancient plants that have undergone heat and pressure over millions of years. 烟煤 is often found in sedimentary rock layers and is mined through both surface and underground methods. Its combustion produces a significant amount of energy, but it also releases pollutants, making its use a topic of environmental concern.