Self-emptying separator

A method for performing a solids discharge in a processing of a flowable product with a separator, the method comprising:

• a. providing a self-emptying separator and processing a flowable product to be processed, separating it at least into a liquid phase and a solid phase, wherein the self-emptying separator includes a rotatable centrifugal drum having a vertical axis of rotation, solids discharge openings, and an emptying mechanism having a piston valve assigned to each of the solids discharge openings, wherein the piston valve is moveable between an opening position and a closing position in a fluid-actuated manner using fluid, wherein the emptying mechanism further comprises a control assembly coupled to the piston valve and configured to control opening and closing movements of the piston valve, wherein the control assembly includes a control unit and a metering device configured to meter and dispense an amount of liquid required for moving the piston valve to the open position, wherein the metering device has a metering element that is displaceable in a metering chamber and which subdivides the metering chamber into a fluid chamber and a pressure chamber for application of compressed air, wherein the metering device has an adjusting system for metering the amount of liquid required for the opening process in the fluid chamber, wherein the adjusting system has a measuring device, wherein the measuring device is configured to measure based on a fluidic measuring principle, and wherein the measuring device is a pressure measuring device arranged in the pressure chamber, wherein the pressure measuring device is configured to measure pressure in the pressure chamber, wherein the pressure in the pressure chamber forms a basis for the metering of the amount of liquid required to move the piston valve to the open position;
• b. opening a filling valve, causing the metering element to move towards of the pressure chamber due to the incoming fluid, wherein the pressure in the pressure chamber increases;
• c. performing a measurement or repeated measurements in or on the pressure chamber with the measuring device and comparing a measurement result with a preset value manually or with a control unit, wherein in step c) the pressure in the pressure chamber is measured with the pressure measuring device and the measured pressure is compared with a predetermined pressure as default value manually or with a control device;
• d. closing the filling valve when the measured value corresponds to the default value so that a metered opening fluid volume is present in the fluid chamber, wherein in step d) a closing of the filling valve takes place when the measured pressure corresponds to the predetermined pressure so that the metered opening fluid volume is present in the fluid chamber;
• and
• e. opening the opening fluid valve and a venting valve of a compressed air line to inject the metered opening fluid volume in the fluid chamber into the separator via an opening fluid supply and an injection chamber for opening fluid, to open the piston valve and to thereby move the piston valve from a closed position to an open position so that the solids discharge openings are released and the solids phase is discharged from the centrifugal drum.