Self-emptying separator

Abstract

The invention relates to a self-emptying separator, comprising a rotatable centrifuge drum (1) with a vertical axis of rotation, the centrifuge drum being provided with a solids discharge opening (7), the solids discharge opening being provided with an emptying mechanism having a piston slide valve (6), the piston slide valve being fluid-operable, in particular being moved by means of a fluid, into an open position and a closed position, the emptying mechanism also having a control device (28) provided for the piston slide valve (6) for controlling the opening and closing movement of the piston slide valve, the control device being provided with a controller (24) and a metering device (14) for metering and outputting a fluid quantity, in particular a liquid quantity, required for opening, the metering device (14) having a metering element (17) movable in a metering chamber (16), the metering element dividing the metering chamber (16) into a fluid chamber (18) and a pressure chamber (19) for applying compressed air, the metering device (14) having a regulating system for metering a fluid quantity, in particular a liquid quantity, required for opening in the fluid chamber (18), the regulating system having a measuring device (15) based on a fluid measurement principle.

Description

Technical Field

[0001] The invention relates to a self-emptying separator and a method for treating centrifuged material. Background Art

[0002] Discontinuously emptied separators in the sense of this document have, in addition to one or more outlets for one or more liquid phases, an emptying device with a piston slide valve which can be moved fluidically, in particular with a liquid as the fluid, alternately into an open position and a closed position, whereby the solids discharge opening in the drum wall is released (open position) and closed (closed position) in the piston slide valve. In the open position, the solid phase is discharged from the centrifuge drum. In the closed position, this is not the case.

[0003] In order to ensure the precise function of such a drum emptying system of a self-emptying separator, the self-emptying separator can include a fluid conveying and discharge system with a piston valve. The fluid conveying and discharge system is used to fill the chamber on the piston slide valve with a fluid (liquid) and to enable the fluid to escape from the chamber on the piston slide valve in order to empty the solids, so that the piston slide valve can move. Thus, in a separator with a vertical axis of rotation, the fluid can escape, for example, below the piston slide valve, so that the product in the drum presses it vertically downwards. Here, the goal is to supply the hydraulic system of the centrifuge drum with a liquid volume that is measured as accurately as possible in a short time during emptying ("opening the fluid"). The emptying amount is therefore determined by the volume of the opening fluid.

[0004] In many separation processes, it is advantageous to be able to flexibly set or adjust or generally change the emptying volume via an electronic control. The challenge here is to reliably meter a fluid volume that is variable as required and measured as accurately as possible for specific needs, even if the pre-pressure in the fluid supply is subject to significant fluctuations.

[0005] In order to meter the volume of the opening fluid, a metering device is used according to patent document DE 3115875 C1, which has a housing and a metering element guided movably in the housing, which can be, for example, a metering piston or a metering diaphragm. If the housing is filled with fluid, the metering element is moved and pressed against the stop of the adjusting screw. The amount of liquid measured in this way is then used as the opening fluid, for example to open a piston valve in a centrifuge drum. For this purpose, the metering element is pneumatically pressed back into the end position, for example, so that the fluid can be delivered in the corresponding valve position or is also delivered to the centrifuge drum and then to the piston valve.

[0006] By moving the adjusting screw, the stop position for the metering element is changed when necessary, which in turn changes the amount of liquid measured by the metering device. However, this means that the operator must manually set the respectively required emptying volume directly on the machine. In DE 31 15 875 C1, a deformable diaphragm is used as the metering element.

[0007] A variant of such a metering device is described in DE 10 2005 049 941 A1. Here, a metering piston guided in a cylinder as a housing is used as a metering element. The stroke of the metering piston is limited by a screw, which forms a stop for the metering piston. The position of the stop can be adjusted electrically so that the volume of the opening fluid can be set or, if necessary, automatically adjusted by an electronic control.

[0008] Metering devices according to the prior art have proven themselves in practice, but these solutions require mechanical adjustment elements for metering in order to be able to move the piston to the desired position by means of a threaded spindle. This can be a hindrance in the case of highly dynamic requirements for the adjustment process for discharging solids. Summary of the invention

[0009] The object of the present invention is to eliminate the above-mentioned problems.

[0010] According to the present invention, a self-emptying separator is proposed, which includes a rotatable centrifuge drum with a vertical rotation axis, the centrifuge drum is provided with a solid discharge opening, and the solid discharge opening is equipped with an emptying mechanism with a piston slide valve, which can be fluid-operated, especially moved to an open position and a closed position by means of liquid, wherein the emptying mechanism also has a control device equipped with the piston slide valve for controlling the opening and closing movement of the piston slide valve, the control device is provided with a controller and a metering device for metering and outputting the amount of fluid, especially the amount of liquid, required for opening, wherein the metering device has a metering element movable in a metering chamber, the metering element dividing the metering chamber into a fluid chamber and a pressure chamber for loading compressed air, and the metering device has a regulating system for metering the amount of fluid, especially the amount of liquid, required for opening in the pressure chamber, the regulating system having a measuring device.

[0011] According to the invention, which is particularly simple to implement and nevertheless operates precisely, it is also provided that the measuring device is based on a fluid measuring principle. Preferably, no mechanical adjusting elements, such as a threaded spindle for setting the opening fluid volume, are required. Thus, the metering device can also advantageously meet the very high dynamic requirements of the regulating process for discharging solids.

[0012] According to the invention, it is further provided that the regulating system with a measuring device based on a fluid measurement principle comprises a pressure measuring device arranged in the pressure chamber, with which the pressure in the pressure chamber can be determined, wherein the pressure in the pressure chamber is or forms the basis for metering or for metering the amount of liquid required for the opening. In this way, the features of the contactless measuring principle are realized particularly advantageously and in a structurally simple manner.

[0013] The fluid used for opening is a liquid, preferably water, or another liquid can be used, ie the flowable product to be processed in the separator or a phase of the product.

[0014] In a preferred embodiment of the invention, the control device has an injection chamber for an opening fluid and an injection chamber for a closing fluid, to which fluid, in particular water, can be supplied for activating the opening and closing movements via an opening fluid supply or a closing fluid supply in which an opening fluid valve and a closing fluid valve are arranged, wherein the opening fluid supply is preferably equipped with a metering device. Thus, a device is provided with which a defined amount of solids (phase) can be emptied quickly, reliably and precisely from a separator.

[0015] Here, it is preferably provided that the metering device has a metering element that can be moved in the metering chamber, which divides the metering chamber into a fluid chamber and a pressure chamber for applying compressed air. This advantageously provides a metering device that is structurally simple.

[0016] In particular, it can be advantageously provided that the metering element is a piston. Thus, a robust and precisely usable metering element is provided. However, the metering element can also have a diaphragm which is deformable itself.

[0017] Optionally, it can be provided that the pressure chamber has a temperature sensor. Thus, temperature fluctuations in the pressure chamber of the metering device can be compensated in a structurally simple manner by the control device correspondingly changing or adjusting the pressure setpoint value when the fluid chamber is filled.

[0018] According to another variant of the invention, it can be provided that the pressure chamber is designed to be gas-tight below the metering element, thereby advantageously minimizing adverse influences such as pressure fluctuations or inaccurate measurements of the pressure measuring device and thus inaccurate metering of the opening fluid.

[0019] It is also advantageous that, according to another option, the volume of the pressure chamber is dimensioned in such a way that, even with a maximum filling of the fluid chamber, the pressure in the opening fluid supply device is higher than the counterpressure in the pressure chamber. Thus, a reliable operation of the metering device is achieved by simple structural measures.

[0020] It is also advantageous that, according to one option, a partition is incorporated into the opening fluid supply device. Thus, the inflow of the opening fluid is limited, so that even at high fluid pressures the filling process is slowed down, so that the target position of the metering element can be reliably moved.

[0021] In another advantageous embodiment of the invention, the partition is arranged directly in front of the injection valve. This makes it possible to simply integrate the partition into the opening fluid supply device. For example, it can be integrated into the threaded connection between the pipeline and the valve.

[0022] The invention also provides a method. The advantageous and simple method for carrying out the emptying of solids when processing a flowable product with a separator according to the invention is characterized by the following method steps:

[0023] a) providing one or more self-emptying separators according to the invention and processing a flowable product to be processed, wherein the product is separated into at least a liquid phase and a solid phase;

[0024] b) opening the filling valve, whereby the metering element is moved by the inflowing fluid in the direction of the pressure chamber, wherein the pressure in the pressure chamber increases;

[0025] c) carrying out measurements or repeated measurements in or at the pressure chamber by means of a measuring device and comparing the measurement result with a preset value manually or by means of a controller, wherein in step c) the pressure in the pressure chamber is measured by means of a pressure measuring device and the measured pressure is compared with a predefined pressure as the preset value manually or by means of a controller;

[0026] d) when the measured value corresponds to the preset value, closing the injection valve so that a metered open fluid volume is present in the fluid chamber, wherein in step d), when the measured pressure corresponds to a predetermined pressure, closing the injection valve so that a metered open fluid volume is present in the fluid chamber; and

[0027] e) opening the opening fluid valve and the valve of the compressed air line in order to inject the opening fluid volume metered in the fluid chamber into the separator via the opening fluid supply device and the injection chamber for the opening fluid, and thereby move the piston slide valve from the closed position into the open position, thereby releasing the solid discharge opening and discharging the solid phase from the centrifuge drum.

[0028] This simple and precise method offers at least the advantages also given with regard to the device according to the invention and also enables precise adjustability of the metering volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The present invention is described in more detail below with reference to the accompanying drawings by means of various embodiments. The present invention is not limited to these embodiments, but can be implemented in other ways in a literal sense or in other ways equivalently. In the accompanying drawings:

[0030] Figure 1 A partial cross-sectional view of a centrifuge drum is shown in section as well as a block diagram of an emptying mechanism of the centrifuge drum for the solid phase;

[0031] Figure 2 A sectional view of a metering device according to the invention and a block diagram of the metering device are shown, wherein the metering device is shown in a first position;

[0032] Figure 3 A sectional view of the metering device and a block diagram of the metering device are shown, wherein the metering device is shown in a second position. DETAILED DESCRIPTION

[0033] An exemplary embodiment is described in the following description of the figures. Individual features of this exemplary embodiment can also be combined with exemplary embodiments not shown and are also suitable as advantageous embodiments in each case.

[0034] Figure 1 A lateral partial area of ​​the lower part of a rotatable centrifuge drum 1 of a centrifuge designed as a separator is shown. The centrifuge drum 1 can have a vertical axis of rotation D.

[0035] The centrifuge drum can be designed as a single cone and / or as in the present case as a double cone (lower and / or upper and in particular inner). The centrifuge drum 1 is preferably designed for continuous operation.

[0036] The centrifuge drum 1 can have a drum lower part 2 and a drum upper part 3. These drum parts 2, 3 can be connected to one another in different ways with the locking ring 27.

[0037] Arranged in the centrifuge drum 1 are a distributor 4 for feeding the product and a disk package 5 consisting of separation disks.

[0038] The inlet pipe and the liquid outlet are not shown. They can be realized in any way.

[0039] The emptying mechanism is used to discharge the solid phase and has a piston slide valve 6 for opening and closing solid discharge openings 7, which can be arranged distributed in the circumferential direction in the region of the maximum diameter of the centrifuge drum 1. The emptying mechanism also includes a control device 28 assigned to the piston slide valve 6 for controlling the opening and closing movement of the piston slide valve.

[0040] The control device 28 has a controller 24. The control device 28 also includes an injection chamber 8 for opening fluid and an injection chamber 9 for closing fluid, to which fluid, in particular water, can be introduced for activating the opening and closing movements via an opening fluid supply device 10 and a closing fluid supply device 11 in which an opening fluid valve 12 and a closing fluid valve 13 are arranged.

[0041] The opening fluid supply device 10 is equipped with a metering device 14 which is connected upstream of the opening fluid valve 12 .

[0042] Metering device 14 (see also Figure 2 ) has a metering element 17 that can move, in particular move, in a metering chamber 16, which divides the metering chamber 16 into a fluid chamber 18 and a pressure chamber 19 for applying a fluid, in particular a gas such as compressed air. The metering element 17 is implemented as a movable piston. Instead of the piston, a movable, in particular deformable diaphragm can also be used as the metering element 17.

[0043] The fluid chamber 18 is formed between the filling valve 21 and the opening fluid valve 12 and the metering element 17 .

[0044] Furthermore, a compressed air line 22 opens into the pressure chamber 19 , into which a valve 23 is connected. The control inputs of all controllable valves can be connected to a control unit 24 .

[0045] The piston valve 25 embedded in the wall of the centrifuge drum 1 serves for the controlled discharge of the fluid used to carry out the opening and closing movement of the piston slide valve 6 (see Figure 1 ).

[0046] Furthermore, a diaphragm can be additionally installed in the fluid supply line 20 in order to limit the inflow of the opening fluid and thereby slow down the filling process even at high fluid pressures, so that a target position of the metering element 17 can be reliably moved to, in which a preselected pressure is achieved. The diaphragm is advantageously located (as viewed in the flow direction) directly in front of the filling valve 21.

[0047] The pressure chamber 19 can be filled with a fluid, in particular air, on a first side, purely diagrammatically "below", of the metering element 17 via a compressed air line 22, so that pressure can build up in the pressure chamber. However, the pressure chamber can also be "vented" via the valve 23. For this purpose, the pressure chamber 19 is correspondingly designed to be gas-tight.

[0048] When the fluid chamber 18 is filled with a fluid, in particular an open fluid, via the fluid supply line 20 on the other side, purely diagrammatically “above”, of the metering element 17, the fluid, in particular air, is compressed in the pressure chamber 19 and a pressure increase occurs in the pressure chamber 19 on the first side, “below”, of the metering element 17, wherein the pressure increase in the pressure chamber 19 is substantially proportional to the change in position of the metering element 17 in the metering chamber 16 (here, by way of example, from Figure 2 starting from the location of the

[0049] A measuring device 15 is arranged in the pressure chamber 19 or is connected to the pressure chamber 19 , so that the pressure in the pressure chamber 19 can be determined by means of the measuring device.

[0050] The pressure in the pressure chamber 19 can be measured once or repeatedly by means of the pressure measuring device 15 so that the position of the metering element 17 can be determined by comparison with a pre-stored table or a stored functional relationship etc. This position in turn enables the current fluid volume in the fluid chamber 18 to be determined.

[0051] For this purpose, it can be provided that the measured pressure value is transmitted to the controller 24, so that based on the measured value the volume of the supplied fluid can be determined by measurement by the controller 24 or by the controller 24 repeatedly and thus also precisely regulated. When the desired filling or the desired pre-set metering volume is reached or set, the filling of the fluid chamber 18 can be stopped.

[0052] Alternatively, the pressure value at the pressure measuring device 15 can also be read manually and used in this way for the setting.

[0053] In this way, the metering device 14 here has a control system for measuring the amount of liquid for actuating the drain mechanism (here the opening fluid volume), which is based on the fluid measurement principle. Variants of the system shown can be implemented within the skill of a person skilled in the art.

[0054] The volume of the pressure chamber 19 on the first side of the metering element 17 and the volume of the fluid chamber 18 on the other side of the metering element 17 are preferably each dimensioned such that even in the case of maximum filling of the fluid chamber 18 the pressure in the fluid supply line 20 is higher than the counterpressure in the pressure chamber 19 .

[0055] Temperature fluctuations can be compensated for by means of an additional temperature sensor (not shown) in the pressure chamber 19 by the control unit 24 changing the pressure target value accordingly when the fluid chamber 18 is filled.

[0056] The function of the device when processing centrifugal material is briefly summarized as follows:

[0057] exist Figure 2 In the first position of the metering device 14 shown in FIG. 1 , the metering element 17 is positioned "above" or toward the fluid chamber 18, so that the volume of the fluid chamber 18 is small. The pressure chamber 19 is at ambient pressure. Alternatively, the pressure chamber 19 can also have a defined pre-pressure. The filling valve 21 is closed toward the fluid chamber 18. The open fluid valve 12 is closed. The valve 23 of the compressed air line 22 is also closed.

[0058] Now, the filling valve 21 is opened. By the inflowing fluid, the metering element 17 moves downward into the second position, as in Figure 3 As shown in FIG. 1 , the measured value of the pressure in the pressure chamber 19 increases. If the measured value reaches a preselected setpoint value, which corresponds to a defined fluid volume in the fluid chamber 18, the filling valve 21 is closed manually or automatically by means of a controller 24. For example, the pressure in the pressure chamber can advantageously form the basis for metering the amount of liquid required for opening.

[0059] The opening fluid valve 12 and the valve 23 in the compressed air line 22 are now opened so that the metered opening fluid volume in the fluid chamber 18 can be injected into the drum via the opening fluid supply device 10 for the opening fluid and the injection chamber 8, the piston valve 25 is opened and the piston slide valve 6 is thereby moved (here vertically downward) into the open position, thereby releasing the solid discharge opening 7 and discharging the solid phase from the centrifuge drum 1.

[0060] Thus, the measuring principle can be a contactless measuring principle. Preferably, no mechanical adjustment elements, such as a threaded spindle for adjusting the opening fluid volume, are required. Thus, the metering device 14 can also advantageously meet very high dynamic requirements for the regulation process of solid discharge.

[0061] The control unit 24 can be controlled by means of a computer program product which takes over the separator control and regulation and optionally also controls the actuation of the piston slide valve, in particular also the metering, in particular also the execution and implementation of the measurements.

[0062] Existing centrifuges having a metering device with a mechanical adjusting element for measuring the opening fluid volume can advantageously be retrofitted or converted with the metering device 14 according to the invention in a simple manner, since often only the mechanical adjusting element (such as a screw) must be replaced by the measuring device 15 and the software of the controller must be adjusted.

[0063] Reference numerals

[0064] 1 Centrifuge drum

[0065] 2. Lower drum parts

[0066] 3. Drum upper parts

[0067] 4 Distributor

[0068] 5-disc set

[0069] 6-piston spool valve

[0070] 7 Solids discharge opening

[0071] 8. Injection chamber for opening the fluid

[0072] 9 Injection chamber for closing chamber

[0073] 10 Open the fluid supply

[0074] 11. Shut off the fluid supply.

[0075] 12 Open the fluid valve

[0076] 13 Close the fluid valve

[0077] 14 Measuring device

[0078] 15. Measuring device

[0079] 16. Measuring Room

[0080] 17 Metering element

[0081] 18 Fluid Chamber

[0082] 19 Pressure Chamber

[0083] 20 Fluid input pipeline

[0084] 21 Injection valve

[0085] 22 Compressed air pipeline

[0086] 23 valves

[0087] 24 Controllers

[0088] 25 piston valve

[0089] 27 Locking ring

[0090] 28 Control Devices

[0091] D Rotation axis

Claims

1. A self-emptying separator, comprising a rotatable centrifuge drum (1) with a vertical rotation axis, the centrifuge drum being provided with a solid discharge opening (7), the solid discharge opening being provided with an emptying mechanism having a piston slide valve (6), the piston slide valve being fluid-operated and movable into an open position and a closed position, the emptying mechanism also having a control device (28) assigned to the piston slide valve (6) for controlling the opening and closing movement of the piston slide valve, the control device being provided with a controller (24) and a metering device (14) for metering and outputting the amount of fluid required for the opening movement, the metering device (14) having a metering element (28) movable in a metering chamber (16) 17), the metering element divides the metering chamber (16) into a fluid chamber (18) and a pressure chamber (19) for loading compressed air, the metering device (14) has a regulating system for metering the amount of fluid required for the opening movement in the fluid chamber (18), the regulating system has a measuring device (15), the measuring device is based on the fluid measurement principle, and the regulating system with the measuring device based on the fluid measurement principle includes a pressure measuring device (15) arranged in the pressure chamber (19), the pressure in the pressure chamber (19) can be determined by means of the pressure measuring device, and the pressure in the pressure chamber (19) forms the basis for metering the amount of fluid required for the opening movement.

2. The self-emptying separator according to claim 1, characterized in that The control device (28) has an injection chamber (8) for an opening fluid, to which fluid can be supplied via an opening fluid supply device (10) in which an opening fluid valve (12) is arranged, in order to activate an opening movement.

3. The self-emptying separator according to claim 1 or 2, characterized in that The metering element (17) is designed as a piston or a diaphragm.

4. The self-emptying separator according to claim 1 or 2, characterized in that The pressure chamber (19) has a temperature sensor.

5. The self-emptying separator according to claim 2, characterized in that The pressure chamber (19) can be filled with fluid on a first side of the metering element (17) via a compressed air line (22), and the fluid chamber (18) can be filled with fluid on the other side of the metering element (17) via a fluid supply line (20), the volume of the pressure chamber (19) being dimensioned such that, even in the case of maximum filling of the fluid chamber (18), the pressure in the fluid supply line (20) is higher than the counterpressure in the pressure chamber (19).

6. The self-emptying separator according to claim 2, characterized in that The fluid chamber (18) is connected between the injection valve (21) and the opening fluid valve (12).

7. The self-emptying separator according to claim 5, characterized in that A partition is installed in the fluid input pipeline (20).

8. The self-emptying separator according to claim 7, characterized in that The fluid chamber (18) is connected between the injection valve (21) and the open fluid valve (12), and the partition is arranged directly in front of the injection valve (21).

9. The self-emptying separator according to claim 1, characterized in that The piston slide valve can be moved into an open position and a closed position by means of a fluid.

10. The self-emptying separator according to claim 1, characterized in that The fluid amount is a liquid amount.

11. The self-emptying separator according to claim 2, characterized in that The fluid is water.

12. Method for carrying out the emptying of solids when processing a flowable product with a self-emptying separator according to any one of claims 1 to 11, characterized in that The method comprises the following method steps: a. Providing a self-emptying separator according to any one of claims 1 to 11 and processing a flowable product to be processed, the product being separated into at least a liquid phase and a solid phase; b. opening the injection valve (21), so that the metering element (17) moves toward the pressure chamber (19) through the inflowing fluid, and the pressure in the pressure chamber (19) increases; c. carrying out measurements or repeated measurements in or at the pressure chamber (19) using a measuring device (15) and comparing the measurement results with a preset value manually or using a controller (24), wherein in step c), the pressure in the pressure chamber is measured using the pressure measuring device (15) and the measured pressure is compared with a predefined pressure as the preset value manually or using a controller (24); d. When the measured value corresponds to the preset value, the injection valve (21) is closed, so that a measured open fluid volume exists in the fluid chamber (18), wherein in step d), when the measured pressure corresponds to a predetermined pressure, the injection valve (21) is closed, so that a measured open fluid volume exists in the fluid chamber (18); e. Opening the opening fluid valve (12) and the valve (23) of the compressed air line (22) so that the opening fluid volume metered in the fluid chamber (18) is injected into the separator via the opening fluid supply device (10) and the injection chamber (8) for the opening fluid, opening the piston valve (25) and thereby moving the piston slide valve (6) from the closed position to the open position, thereby releasing the solid discharge opening (7) and discharging the solid phase from the centrifuge drum (1).

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