A decanter centrifuge has a hollow, rotatable drum with a screw conveyor comprising a core body, in which an inlet opening for material into the drum from an inlet chamber is provided, the inlet opening having a delimitation surface which is rear relative to the direction of rotation and extending substantially axially, said delimitation surface being provided with a wear reinforcement member. The dispenser includes first and second members pivotally connected together by a first hinge to form a first entrance into the dispenser. Charged polymer chains and counterions may be combined with a photosensitive compound to form photosensitive aggregates, and then nanoparticles may be combined with the aggregates to form the microcapsules. A power up signal drive unit of the circuit activates the power up signal in response to the detection signal and drives the power up signal in response to the control signal. The local telephone converts the voice signal to a text signal responsive to storing the voice signal. The main filter element is preferably made from high-density polyethylene porous filter media.