Sawdust has a low ash content and high carbon content (50% w/w), making it ideal for making charcoal briquettes for residential cooking.
https://www.ftmmachinery.com/blog/biomass-charcoal-briquette-philippines.html
Here is the sawdust charcoal briquette production process:
1 Collect sawdust:
Collect sawdust from wood processing plants, furniture manufacturing factories, or other sources.

2 Drying
Dry the sawdust in the sun or a sawdust rotary dryer to remove extra moisture. Sawdust with a high moisture content will not carbonize properly and may produce low-quality charcoal.

3 Carbonization:
The dried sawdust is then carbonized at a temperature about 300°C to 500°C for several hours until it turns into charcoal.

4 Crush and sieve the charcoal:
The charcoal is then crushed into small pieces and sieved by a 60 mesh filter.

5 Prepare the binder:
Mix the tapioca with water in a pan and then heat on the stove until the mixture coagulates.

6 Mix the charcoal with the binder:
The charcoal is mixed with the binder at a ratio of 1:3 (charcoal to binder).

7 Briquetting:
Compress the mixture with a charcoal briquette machine to obtain briquettes with desired shape and size.

8 Drying:
The briquettes are then dried in the sun or using a dryer to reduce their moisture content and make them easier to handle and store.

9 Packing and storage:
The final step is to pack the briquettes in bags or boxes and store them in a dry place away from moisture and direct sunlight.

Note: To increase the calorific value of biomass charcoal briquettes, you can mix in coal powder, charcoal dust, carbonized coconut shells, carbonized straw, etc.