Fuente: Wipo "digitalization" The invention discloses a progressive sewage treatment device and a treatment method. The progressive sewage treatment device comprises a main shell, a sewage inlet, a sewage outlet, a filter screen plate, a stirring roller, a driving motor, a flocculant inlet pipe, a sludge discharge pipe, an air supply type locking mechanism and an air supply main channel. The filter screen has the following advantages and effects that the two air supply type locking mechanisms are arranged to lock the first filter screen plate and the second filter screen plate respectively, and the air supply main channel is arranged to be connected with the two air supply type locking mechanisms, so that the first filter screen plate and the second filter screen plate can be locked only by feeding air into the air supply main channel; the two air supply type locking mechanisms can be controlled, and the structure can be effectively simplified through a single-input and double-control output mode; and the first filter screen plate and the second filter screen plate have the advantage of being convenient to mount/dismount.