The invention relates to a decanter centrifuge with a rotating bowl (1) provided with at least one solids discharge port and at least one clarified liquid discharge port and a screw conveyor (2) disposed coaxially within said rotating bowl (1) rotated in the same direction with a differential rotational speed, where a feed suspension to be separated is introduced into a ring shaped space formed between said rotating bowl (1) and said screw conveyor (2) through a central feed pipe (10) fixed to the end of the screw conveyor (2) and supported in at least one bearing (16) and can be separated by centrifugal force into a solid and a liquid phase so that said solid phase is discharged from said solid discharge port and said liquid phase is discharged from said clarified liquid discharging apparatus (5). According to the present invention it is characterized by a liquid phase conduit (4) arranged in the hollow shaft of the rotating bowl (1) guiding the liquid phase outside of the bearings, a liquid phase discharge valve provided outside the bearing (16; 18) on the side facing away from the bowl (1) and screw (2) and a sealing at the end of the feed pipe (10) surrounded by the liquid phase conduit (4). So it is possible to pressurise the system and to use the pressure from the feed pump to support the cake transport in the solids transporting part of the bowl, thereby eliminating the need for variable speed conveyor control and equipment.