After reading about the process of making charcoal from sawdust, we know that the weight loss happens in three stages: drying, briquetting, and carbonization
To get 1 ton of charcoal, we need to carbonize around 3 tons of sawdust briquettes. The sawdust briquettes are carbonized by a carbonization furnace or earthen kiln. In this step, the weight of sawdust briquettes will shrink greatly.
To make 3 tons of sawdust briquettes, we need at least 3 tons of dried sawdust with a moisture of <12%. From sawdust to briquettes, the needed machine is a sawdust briquette machine. In this process, sawdust moisture will reduce little, it can be neglected.
To make sawdust briquettes, the sawdust needed to be dried at <12% moisture. Therefore, the carbonization rate ultimately depends on the humidity of the raw material.
The moisture of naturally dried materials is around 20%. After being dried by the sawdust dryer, the water content can be reduced to around 10%. To get 3 tons of 10% moisture sawdust, we need to dry around 3.5 tons of 30% moisture sawdust.
For the fresh biomass materials, humidity can reach 50%-60%, it will need 6-7 tons of wet materials to get 3 tons of 10% moisture sawdust.