Sewage treatment method and equipment thereof

The invention relates to a sewage treatment method. The method comprises the following steps of: excess sludge which has solid content ratio of 3 to 10 percent and is obtained from an aeration tank for sewage treatment or an aeration zone of a biological reaction tank by treatment of concentration or dehydration is introduced into ultrasonic equipment for ultrasonic treatment for 30 to 120 seconds with the frequency of 20 to 100 kHz and power density of 30 to 180W/L, then the obtained excess sludge is introduced into a hydrolytic acidification tank stored with sludge, wherein the control conditions of utilizing and controlling the amount of the sludge treated by introducing the ultrasonic wave comprises the temperature of 10 to 60 DEG C and pH of 3 to 10, followed by natural deposition and hydrolysis under the condition for 8 to 96 hours, after the hydrolysis is completed, the treated sludge is put back to an anoxic zone of the biological reaction tank or a preparatory reaction zone, a middle tank or an anoxic digestion tank for sewage treatment, and a certain reaction time is maintained. The method exerts the advantages of ultrasonic wave breaking down cells, simultaneously absorbs the advantage that hydrolytic action can convert macromolecules into micromolecular substances which are easy to be utilized by microorganisms, and achieves the development of internal carbon sources of the sludge at utmost.