A filter structure has a main body and a stirring member. The main body has a hollow containment space filled with a filtering material. A filtering mesh is disposed at a bottom side of the containment space. A first purifying opening is disposed at a top end of the main body. A second purifying opening is disposed at a lower sidewall position of the main body above the filtering mesh. A first cleaning opening and a second cleaning opening are disposed on the main body and respectively coupled to a first and second inner pipe. An outlet is disposed at a bottom of the main body. The stirring member has an upper cover corresponding to the first purifying opening of the main body. The upper cover further has a driving arm and a connecting rod, and the connecting rod has a plurality of stirring rods.

A filter structure has a main body and a stirring member. The main body has a hollow containment space filled with a filtering material. A filtering mesh is disposed at a bottom side of the containment space. A first purifying opening is disposed at a top end of the main body. A second purifying opening is disposed at a lower sidewall position of the main body above the filtering mesh. A first cleaning opening and a second cleaning opening are disposed on the main body and respectively coupled to a first and second inner pipe. An outlet is disposed at a bottom of the main body. The stirring member has an upper cover corresponding to the first purifying opening of the main body. The upper cover further has a driving arm and a connecting rod, and the connecting rod has a plurality of stirring rods.

An air purifier comprises: a columnar hollow filter, a fan, an impurity scraping member and an impurity accommodation member. The fan starts and then draws external air through a sidewall of the columnar hollow filter into its cavity, the air is filtered and purified as it passes through the columnar hollow filter, thereby discharging clean air. Impurities attached to the air are accumulated on a surface of the columnar hollow filter; when the impurities accumulated on the surface of the columnar hollow filter reach a certain amount, the columnar hollow filter moves relative to the impurity scraping member, the impurity scraping member scrapes off the impurities from the surface of the columnar hollow filter into an accommodation chamber of the impurity accommodation member. The impurity accommodation member can temporarily store the impurities, thereby improve filtration quality of the air purifier and reduce replacement frequency of the filter element.

A solid-liquid filtration assembly for removing solids from a solid-liquid mixture includes a filter module comprising a pan, to which a screen is attached, and a scraping arm, to which is attached slurry nozzles. A media bed on the screen separates solids from a mixture of a liquid and the solids. Filtrate drains from the pan via a drain tube. A scraping arm removes dewatered solids and soiled media from atop the media bed, forward of the scraping arm. The scraping arm also expels the dewatered solids and the soiled media from the pan, while slurry nozzles deliver the mixture to the media bed aft of the scraping arm.