Lignite, often referred to as brown coal, is a soft brown combustible sedimentary rock formed from naturally compressed peat. It is considered the lowest rank of coal due to its relatively low heat content. It has a carbon content around 25-35%. It is mined in China, Bulgaria, Greece, Germany, Poland, Serbia, Russia, Turkey, the United States, Canada, India, Australia, and many other parts of Europe and it is used almost exclusively as a fuel for steam-electric power generation, but is also mined for its germanium content in China. About 26.3% of Germany's electricity comes from lignite power plants,while in Greece, lignite provides about 50% of its power needs.

 

With different characteristic of lignite,we built heating chamber following drying temperature in four stage.

 

Primary drying are at 400 ℃, high humidity state to remove most of the water to ensure that the chemical composition of lignite does not change and difficult to burn.Secondary drying zone temperature 300 ℃, temperature strength by the wind high yield in addition to water, to ensure lignite not coking.Third drying zone temperature at 120 ℃ -210 ℃, equipped with drum crushing device to break lignite quickly for smoothly discharging.Fourth drying zone is high exhaust area, room temperature 60 ℃ -80 ℃, rely on negative pressure of cool air from the wind system.For final dry lignite should be kept in cool and dry storage condition.