Sludge treatment system and method for treating sludge therewith

The invention provides a sludge treatment system and a method for treating sludge therewith. The sludge treatment system comprises a steam generating device and a pyrohydrolysis device. The pyrohydrolysis device preheats a pyrohydrolysis device by using steam output from the steam generating device; after the pyrohydrolysis device reaches a preheating temperature, sludge is received; the sludge inthe pyrohydrolysis device is allowed to undergo pyrohydrolysis in virtue of the steam output from the steam generating device; the sludge having undergone pyrohydrolysis is cooled and depressurized by an energy recovery device; discharged pyrohydrolyzed sludge passes through a dehydration drying device and forms granular biochar soil with a solid content of 65% to 78%; and in the whole process oftreatment, malodorous gas is removed by a malodorous gas treatment device. The sludge treatment system and the method of the invention allow the sludge to undergo thorough pyrohydrolysis without chemical reagent; the dehydrat