Method for the liquid solid separation of material mixtures and suspensions in which the material mixture under pressure is fed into a closed chamber having at least one filter surface and a hydrostatic pressure is generated within said chamber for separating the liquid phase. After separating the liquid phase the chamber is opened and the filter surface together with the filter cake is removed from said chamber. The material mixture firstly is treated by the means of hydrostatic pressure of about up to 0.2 bar, wherein 80 to 90% of the fed volume is removed as filtrate. Thereafter the concentrated remaining volume is drawn off and is further treated in the closed chamber with a pressure of up to 5 bar. By reducing the volume of the chamber finally with a pressure of up to 50 bar the remaining filtrate is separated.