Method for preparing charcoal by pyrolyzing sludge based on microwave-induced directional heating technology

The invention relates to a method for preparing charcoal by pyrolyzing sludge based on a microwave-induced directional heating technology, and relates to the technical field of resource utilization ofmunicipal sludge resources. The method comprises the following steps of (1) drying the sludge, crushing, sending into a pyrolyzing furnace, and primarily pyrolyzing, so as to obtain the semi-pyrolyzed sludge; (2) performing microwave-induced pyrolyzing on the semi-pyrolyzed sludge in step (2), and cooling, so as to obtain the sludge charcoal. The method has the advantages that the semi-pyrolyzedsludge with microwave-enhanced absorbance property and high property is obtained by the primary pyrolyzing; the heavy metals are pyrolyzed, enhanced, vitrified and cured by high-energy sites of a substrate in situ, and the purpose of preparing the high-property sludge charcoal at low energy consumption is realized; on the basis of no additional physical/chemical activating additive, the heavy metal in the sludge is safely