Patent ID: 7131540

Claim:
A reverse flow filter system ( 3 ) having a reverse flow filter with an inlet ( 5 ) for a liquid to be prepared containing the substances to be separated, with an outlet ( 7 ) conducting the filtrate as prepared liquid to an associated liquid system ( 23 ), and with an outlet ( 9 ) for reverse flow volumes charged with separated substances, a closing valve ( 13 ) for closing and opening the outlet ( 9 ) for the reverse flow volumes, a filter mechanism ( 33 ) for separation of residual liquid from a mud-like mass which contains substances separated in the separating device ( 1 ), and an assembly ( 35 ) for return of the residual liquid to the liquid system ( 23 ) as prepared liquid, characterized in that a separating device is present for separating solids from the reverse flow volume, having a spinning screen in the form of a drum screen ( 17 ) with annular screen wall ( 21 ), a spray tube ( 15 ) conducting the liquid to the drum screen ( 17 ), which spray tube ( 15 ), with respect to its opening ( 26 ), extends at least in approximation tangentially on the inside of the screen wall ( 21 ) of the drum screen ( 17 ) in order to generate a spin flow of the liquid on the screen wall ( 21 ) and is connected by way of a line to the outlet ( 9 ) for the reverse flow volume, a housing ( 19 ) enclosing the drum screen ( 17 ) to receive liquid penetrating the screen wall ( 21 ), and an outlet ( 29 ) positioned on the bottom ( 27 ) of the drum screen ( 17 ) for discharge of the substances separated, and in that the separating device is mounted upstream from the filter mechanism.