Tubular sawdust briquettes produced by compressing sawdust, which are then carbonized into sawdust charcoal, are classified as a new type of fuel in the rural energy industry. Recently, this charcoal has boasted promising export prospects and favorable pricing, which has led many rural energy enterprises to launch related projects. However, the entire process from sawdust compression to carbonization entails stringent technical requirements; failure to comply with these requirements may easily result in project setbacks. Today, experts in sawdust pneumatic drying will elaborate on the critical pre-compression sawdust drying process.
If sawdust drying for charcoal production is uneven, “pop-off” incidents may occur during compression, compromising the compactness of the finished briquettes. Conversely, high-temperature drying can cause carbon chain cracking, leading to insufficient structural strength of the final charcoal product. Therefore, sawdust drying is a pivotal step in the entire production process.
Sawdust is ideally suited for drying via a pneumatic drying system, where the material is conveyed by high-temperature airflow in accordance with production volume requirements. In this system, sawdust particles float in the airflow and are fully surrounded by hot flue gas, resulting in an extensive heat exchange surface area and rapid drying speed.
The structural diagram of this equipment is shown above. The system is powered by a high-pressure induced draft fan, which draws cold air into a coal-fired hot air furnace. The air participates in combustion to generate hot flue gas, which is then processed through dust sedimentation and cold air adjustment to produce a heat medium with the desired temperature, before being fed into the drying and conveying pipeline. Sawdust is introduced into the pipeline through a feed inlet and disperser, where it is rapidly carried by the hot airflow and its moisture content is absorbed. By the end of the pipeline journey, the sawdust has been dried to the required moisture level. It then enters a cyclone separator filter, where the dried sawdust is separated and collected. The moist waste gas is discharged through the fan afterward.
This equipment offers rapid and uniform drying, coupled with relatively high thermal efficiency. Moreover, since sawdust does not pass through the fan, there is no fan abrasion. The fan only handles cooled waste gas instead of high-temperature flue gas, preventing fan deformation and damage to bearing lubrication.