After screening trash is conveyed through a drying down about 4.5% moisture. After drying sawdust was drunk puree again pour into the tank. Sawdust is made into wood mulch using screw presses with heating. Density of 1.4 tonnes of wood sawdust? Block. Then the wood shavings into the furnace of coal. Maintain temperature of 700-800 degrees C in 5 days .When volatiles in wood that will fly off the only remaining major component is carbon (charcoal) with a content of> 85%. Than when satisfactory will be bringing out the natural cooling hatched within 2 days. Finally we get the coal sawdust.