Self-discharging separator

Abstract

The present invention relates to a self-draining separator comprising a rotatable centrifugal drum (1) having a vertical rotation axis and a solids discharge opening (7), to which a discharge mechanism having a piston valve (6) is assigned, which is fluid-operated, in particular by a liquid, between an open position and a closed position, the discharge mechanism further comprising a control assembly (28) assigned to the piston valve (6) for controlling the opening and closing operation, the control assembly (28) comprising a control unit (24) and a metering device (14) for metering and dispensing a fluid amount, in particular a liquid amount, required for the opening process, the metering device (14) having a metering element (17) displaceable in a metering chamber (16) and dividing the metering chamber (16) into a fluid chamber (18) and a pressure chamber (19) for the application of compressed air, the metering device (14) comprising a regulating system for metering a fluid amount, in particular a liquid amount, required for the opening process of the fluid chamber (18), the regulating system comprising a measuring device (15).

Description

Technical Field

[0001] The present invention relates to a self-discharging separator described in the first half of claim 1 and a method for treating centrifuged materials described in claim 9.

Background Art

[0002] As defined herein, a separator that discharges discontinuously has a discharge mechanism with a piston valve that is fluid-driven, particularly by a liquid, in addition to one or more outlets for one or more liquid phases. As a result of the piston valve opening (open position) and closing (closed position) the solid discharge opening in the drum wall, the discharge mechanism is alternately moved between the open and closed positions. In the open position, the solid phase is discharged from the centrifuge drum. In the closed position, the solid phase is not discharged from the centrifuge drum.

[0003] To ensure the correct operation of such a drum discharge system of a self-discharging separator, the self-discharging separator has a discharge system with a fluid supply and a piston valve. This serves to fill the chamber on the piston valve with a fluid - a liquid - and to allow the fluid to escape from the chamber on the piston valve in order to discharge solids, and as a result, to enable the piston valve to move. For example, in a separator with a vertical axis of rotation, the fluid can escape under the piston valve, and as a result, the product in the drum pushes the piston valve vertically downwards. The aim here is to supply the hydraulic system of the centrifuge drum with a volume of fluid measured as accurately as possible in a short time during discharge ("opening fluid"). Thus, the volume of the opening fluid determines the discharge amount.

[0004] In many separation processes, it is advantageous to be able to flexibly set, regulate, or more generally change the discharge amount via an electronic control device. The problem here is to vary as required and to reliably meter as accurately as possible the required amount of fluid even if the upstream pressure in the fluid supply is subject to considerable fluctuations.

[0005] According to German Patent Specification No. 3115875, a metering device having a housing and a metering element movably guided within the housing, such as a metering piston or a metering diaphragm, is used for metering the volume of a release fluid. When the housing is filled with fluid, the metering element is moved and pressed against the stopper of the adjusting screw. The amount of liquid thus measured is then used, for example, as a release fluid for opening a piston valve in a centrifuge drum. For this purpose, the metering element is pushed back to its end position, for example by air pressure, so that the fluid can be conveyed into the centrifuge drum and thus to the piston valve in the corresponding valve position.

[0006] By adjusting the setting screw, the stop position of the metering element is changed as required, thereby changing the amount of liquid metered by the metering device. However, this means that the operator has to manually set the required discharge amount directly on the machine. German Patent Specification No. 3115875 uses a flexurally deformable diaphragm as the metering element.

[0007] A variant of this metering device is described in German Patent Publication No. 102005049941. Here, a metering piston guided within a cylinder as the housing is used as the metering element. The stroke of the metering piston is limited by a threaded rod forming the stopper of the metering piston. The position of the stopper is adjusted by an electric motor, and the volume of the release fluid can be set via an electronic control system or, incidentally, automatically adjusted.

[0008] Although the metering devices according to the prior art have actually been well proven, these solutions require the mechanical actuator for metering to move to the desired position of a piston having a threaded spindle. This can be an obstacle when there are high dynamic requirements for the adjustment process for solid discharge. It is an object of the present invention to solve this problem. SUMMARY OF THE INVENTION

Means for Solving the Problem

[0009] The present invention achieves this object by the subject matter of claim 1. Further, a method according to claim 9 is provided.

[0010] According to claim 1, a self-discharging separator is provided, the separator comprising a rotatable centrifugal drum having a vertical axis of rotation and a solid discharge opening, a discharge mechanism having a piston valve being assigned to the centrifugal drum, the piston valve moving between an open position and a closed position in an operating mode by a fluid, in particular a liquid, the discharge mechanism further comprising a control assembly assigned to the piston valve for controlling the opening and closing operation, the control assembly comprising a control device and a metering device for metering and dispensing a fluid quantity, in particular a liquid quantity, required for the opening process, the metering device being displaceable within a metering chamber and having a metering element which divides the metering chamber into a fluid chamber and a pressure chamber for the use of compressed air, the metering device having an adjustment system for metering a fluid quantity, in particular a liquid quantity, required for the opening process of the fluid chamber, the adjustment system having a measuring device.

[0011] According to the present invention, which is particularly easy to implement and operates accurately, it is further shown that the measuring device is based on a fluid measurement principle. Preferably, no mechanical actuator such as a threaded spindle is required to adjust the quantity of fluid for opening. Thus, the metering device can also advantageously meet the very high dynamic requirements in the adjustment process of solid discharge.

[0012] Also according to the present invention, it is further shown that an adjustment system with a measuring device based on a fluid measurement principle has a pressure measuring device arranged in the pressure chamber, the pressure in the pressure chamber can be determined using the pressure measuring device, and this pressure in the pressure chamber is the basis for, or forms, or is for metering the fluid quantity required for the opening process. Thus, the feature of the non-contact measurement principle is implemented in a particularly advantageous and constructionally simple manner.

[0013] The fluid used in the opening process is a liquid, preferably water or a liquid other than water, and such a fluid product can be processed by the separator or phase of this product.

[0014] In a preferred embodiment of the present invention, the control assembly has an injection chamber for the opening fluid and an injection chamber for the closing fluid, and both chambers are supplied with fluid, particularly water, and the opening and closing operations are driven through the opening fluid supply part and the closing fluid supply part respectively, and an opening fluid valve and a closing fluid valve are arranged, and preferably a metering device is assigned to the opening fluid supply part. Thereby, a device is created that can quickly, safely and accurately discharge a defined quantity of solids (solid phase) from the separator.

[0015] In this context, the metering device has a metering element, which is preferably movable within a metering chamber that divides the metering chamber into a fluid chamber and a pressure chamber to which compressed air is applied. This advantageously creates a structurally simple metering device.

[0016] In particular, it is shown to be advantageous for the metering element to be a piston. Thereby, a robust and accurately usable metering element is created. However, the metering element can also essentially have a deflectable diaphragm.

[0017] Incidentally, it is shown that the pressure chamber has a temperature sensor. In this way, temperature fluctuations in the pressure chamber of the metering device can simply be compensated for by the configuration in terms of the control system changing or adjusting the pressure setpoint accordingly.

[0018] According to a further variant of the present invention, it is shown that the pressure chamber under the metering element is configured to be gas-tight. This is advantageous for minimizing adverse effects such as pressure fluctuations or inaccurate measurements of the pressure measuring device, and thus inaccurate metering of the opening fluid.

[0019] Furthermore, according to a further accompanying example, it is advantageous if the volume of the pressure chamber is dimensioned such that even when the fluid chamber is filled to the maximum, the pressure of the fluid supply for opening is still higher than the opposing pressure of the pressure chamber. As a result, a simple structural measure provides for the safe operation of the metering device.

[0020] Furthermore, according to one accompanying example, it is advantageous to install an orifice plate in the fluid supply for opening. This restricts the inflow of the fluid for opening and, as a result, the filling process can be decelerated even under high fluid pressures, so that the target position of the metering element can be safely approached.

[0021] In a variant of a further advantageous embodiment of the invention, the orifice plate is arranged directly upstream of the filling valve. This facilitates the integration of the orifice plate with the fluid supply for opening. For example, it can be integrated into the threaded connection between the pipeline and the valve.

[0022] The invention also provides a method according to claim 9. This advantageous and simple method of discharging solids in the treatment of a flowable product having a separator according to any of the above claims is characterized by the following method steps. a) providing a self-discharging separator according to one or more of the relevant claims and treating the flowable product to be treated to separate the flowable product into at least a liquid phase and a solid phase; b) opening the filling valve, causing the metering element to move towards the pressure chamber due to the inflow of fluid and increasing the pressure in the pressure chamber; c) performing repeated measurements in or on the pressure chamber using a measuring device and comparing the measurement results with a preset value manually or using a control unit, where the pressure in the pressure chamber is measured using a pressure measuring device and the measured pressure is compared with a preset pressure as a default value manually or using a control device; d) A step of closing the filling valve so that the volume of the fluid for opening, which has been measured, exists in the fluid chamber when the measured value corresponds to the default value, wherein the filling valve is closed when the measured pressure corresponds to a predetermined pressure, and as a result, the fluid with the measured volume for opening exists in the fluid chamber; e) Opening the valve of the fluid for opening and the valve of the compressed air line, and injecting the measured volume of the fluid for opening in the fluid chamber into the separator and into the injection chamber for the fluid for opening via the fluid for opening supply section, thereby moving the piston valve from the closed position to the open position, releasing the solid matter discharge opening, and discharging the solid phase from the centrifuge drum.

[0023] This simple and accurate method provides the advantages given at least with respect to the device of claim 1 and also results in an accurate adjustment of the measurement. Even more advantageous configurations of the invention can be found in the dependent claims.

Brief Description of the Drawings

[0024] The present invention will be described in more detail below by way of exemplary embodiments with reference to the drawings. The present invention is not limited to these exemplary embodiments and can also be realized in other ways according to the language or other equivalent methods.

Figure 1

Figure 2

Figure 3

Modes for Carrying Out the Invention

[0025] In the following description of the figures, exemplary embodiments are described. Each individual feature of this exemplary embodiment can also be combined with an exemplary embodiment not shown, and each is suitable as an advantageous configuration of the subject matter recited in one or more of the main claims and the dependent claims.

[0026] FIG. 1 shows a lower cross-section of a rotatable centrifugal drum 1 of a centrifuge configured as a separator. The centrifugal drum 1 has a vertical axis D of rotation. The centrifugal drum is single and / or, as in this case, double conical (bottom and / or top, especially inside). The centrifugal drum 1 is preferably configured for continuous operation.

[0027] The centrifugal drum 1 has a lower drum part 2 and an upper drum part 3. These drum parts 2, 3 can be connected to each other in various ways, such as using a locking ring 27. A distributor 4 for supplying the product to the centrifugal drum 1 and a disk stack 5 of separator disks are arranged.

[0028] The supply pipe and the liquid outlet are not shown. They can be realized in any way. An ejection mechanism is used to discharge the solid phase and includes a piston valve 6 for opening and closing a solid phase discharge opening 7, which is formed circumferentially dispersed in the region of the maximum diameter of the centrifugal drum 1. The ejection mechanism further includes a control assembly 28 associated with the piston valve 6 to control the opening and closing operation of the piston valve 6.

[0029] The control assembly 28 includes a control unit 24. The control assembly 28 further includes an injection chamber 8 for releasing the fluid and an injection chamber 9 for closing the fluid. Fluid, especially water, is supplied via an opening fluid supply section 10 and a closing fluid supply section 11, and an opening fluid valve 12 and a closing fluid valve 13 for driving the opening and closing operation are arranged.

[0030] The fluid supply section 10 for opening is associated with a metering device 14 connected upstream of the fluid valve 12 for opening. The metering device 14 - see also FIG. 2 - has a movable, in particular displaceable, metering element 17 in a metering chamber 16, which divides the metering chamber 16 into a fluid chamber 18 and a pressure chamber 19 and allows a fluid, in particular a gas such as compressed air, to flow in. The metering element 17 is here configured as a displaceable piston. As an alternative to the piston, a movable, in particular essentially flexurally deformable diaphragm can also be used as the metering element 17.

[0031] The fluid chamber 18 is formed between the filling valve 21, the fluid valve 12 for opening, and the metering element 17. The compressed air line 22 to which the valve 23 is connected also opens into the pressure chamber 19. The control inputs of all controllable valves are connected to the control unit 24.

[0032] The piston valve 25 inserted into the wall of the centrifugal drum 1 is used to controllably discharge the fluid used to operate the opening and closing of the piston valve 6 (see FIG. 1).

[0033] Furthermore, an orifice plate can be additionally installed in the fluid supply line 20 to limit the inflow rate (volume) of the fluid for opening, and thus slow down the filling process even at high fluid pressures, so that the target position of the metering element 17 reaching a preselected pressure can be safely approached. The advantageous position of the orifice plate - when viewed in the direction of flow - is immediately upstream of the filling valve 21.

[0034] The pressure chamber 19 can be filled with fluid, in particular air, through the compressed air line 22 on the first side - in this case, "below" the metering element 17 - as a result of which the pressure in the pressure chamber 19 builds up. However, the fluid can also be "released" via this valve 23. The pressure chamber 19 is configured to be correspondingly gas-tight for this purpose.

[0035] When filling the fluid chamber 18 on the other side through the fluid supply line 20 with fluid, particularly release fluid, - here, as purely illustrated, above the metering element 17, - the fluid, particularly air, is compressed within the pressure chamber 19, and a pressure increase occurs within the pressure chamber 19 on the first side "below" the metering element 17. The pressure increase within this pressure chamber 19 is essentially proportional to the change in the position of the metering element 17 within the metering chamber 16, starting here as an example from the position in Figure 2.

[0036] A measuring device 15 is arranged in the pressure chamber 19 or such a measuring device 15 is connected to the pressure chamber 19, whereby the pressure within the pressure chamber 19 can be determined using the measuring device 15.

[0037] By means of the pressure measuring device 15, the pressure within the pressure chamber 19 is measured once or repeatedly and, by comparison with a pre-stored table or stored functional relationship, etc., the position of the metering element 17 can be determined via the pressure measurement. From this position, in turn, it becomes possible to determine the current fluid quantity within the fluid chamber 18.

[0038] For this purpose, the measured pressure value is passed to the control unit 24, and within the control unit 24 or via the control unit 24, the quantity (volume) of the fluid supplied by measurement can be repeatedly determined based on this measured value, and thus the quantity (volume) of the fluid can also be accurately set. The filling of the fluid chamber 18 can be stopped when the desired filling quantity (volume) or the desired pre-set metering quantity (volume) is reached or adjusted.

[0039] Alternatively, the pressure value at the pressure measuring device 15 can be read manually and used in this way for adjustment. In this way, the metering device 14 here has an adjustment system for measuring the quantity of fluid - in this case the volume of the release fluid - and the adjustment system actuates an ejection mechanism based on the fluid measurement principle. Variants of the illustrated system can be implemented within the scope of specialized skills.

[0040] The volume (quantity) 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 dimensioned such that the pressure in the fluid supply line 20 is still higher than the back pressure in the pressure chamber 19, even when the fluid chamber 18 is filled to the maximum.

[0041] By using a further temperature sensor (not shown) in the pressure chamber 19, it is possible to compensate for temperature variations by enabling the control unit 24 to change the pressure setpoint accordingly when filling the fluid chamber 18. The function of this device in the processing of centrifuged material is again briefly summarized.

[0042] In the first position of the metering device 14 shown in FIG. 2, the position of the metering element 17 is "up" towards the fluid chamber 18, as a result of which the volume of the fluid chamber 18 becomes smaller. The pressure chamber 19 is at ambient pressure. Alternatively, the pressure chamber 19 can also have a defined upstream pressure. The filling valve 21 is closed towards the fluid chamber 18. The fluid valve 12 for opening is closed. The valve 23 in the compressed air line 22 is also closed.

[0043] Here, the filling valve 21 is opened. The inflowing fluid moves the metering element 17 downwards to the second position, as shown in FIG. 3, and increases the measured value of the pressure in the pressure chamber 19. When the measured value reaches a preselected setpoint corresponding to the defined fluid volume in the fluid chamber 18, the filling valve 21 - controlled manually or automatically by the control unit 24 - is closed. In this way, for example, the pressure in the pressure chamber can advantageously form the basis for the metering of the fluid volume required for opening.

[0044] The fluid valve 12 for opening and the valve 23 in the compressed air line 22 are opened, and the measured amount of the fluid for opening in the fluid chamber 18 is injected into the drum via the fluid supply section 10 for opening and the injection chamber 8 for the fluid for opening. The piston valve 25 is opened, whereby the piston valve 6 is moved - here vertically downward - to the open position, the solid-phase discharge opening 7 is released, and the solid phase is discharged from the centrifuge drum 1.

[0045] Therefore, the measuring principle can be a kind of non-contact measuring principle. Preferably, a mechanical actuator such as a threaded spindle is not required to adjust the volume of the fluid for opening. Thus, advantageously, the metering device 14 can satisfy even the very high dynamic requirements of the adjustment process for solid matter discharge.

[0046] The control unit 24 can be controlled by a computer program product that takes over the control and regulation of the separator, and can also control, if necessary, the drive of the piston valve, in particular metering, in particular the performance and execution of the measurement.

[0047] Existing centrifuges equipped with a metering device having a mechanical actuator for measuring the volume of the fluid for opening can advantageously be easily retrofitted or converted with the metering device 14 according to the present invention, because in many cases, only a mechanical actuator such as a threaded rod has to be replaced for the measuring device 15, and the software of the control system has to be adapted.

Explanation of reference numerals

[0048] List of symbols 1 Centrifuge drum 2 Lower drum part 3 Upper drum part 4 Distributor 5 Disc stack 6 Piston valve 7 Solid-phase discharge opening 8 Injection chamber for the fluid for opening 9 Injection chamber for the closing chamber 10 Fluid supply part for opening 11 Fluid supply part for closing 12 Fluid valve for opening 13 Fluid valve for closing 14 Measuring device 15 Measuring device 16 Measuring chamber 17 Measuring element 18 Fluid chamber 19 Pressure chamber 20 Fluid supply line 21 Filling valve 22 Compressed air line 23 Valve 24 Control unit 25 Piston valve 27 Lock ring 28 Control assembly D Rotating shaft

Claims

1. A self-discharging separator comprising a rotatable centrifugal drum (1) having a vertical axis of rotation and a solids discharge opening (7), The centrifugal drum (1) is assigned a discharge mechanism having a piston valve (6), the piston valve (6) moves between an open position and a closed position in a fluid operating mode by means of a liquid, and the discharge mechanism further comprises a control assembly (28) assigned to the piston valve (6) for controlling the opening and closing movement. The control assembly (28) comprises a control unit (24) and a metering device (14) for metering and distributing the amount of fluid which is the amount of liquid required for the opening process. The metering device (14) is displaceable within a metering chamber (16) and has a metering element (17) which divides the metering chamber (16) into a fluid chamber (18) and a pressure chamber (19) for the use of compressed air. The metering device (14) has an adjustment system for metering the amount of fluid which is the amount of liquid required for the opening process of the fluid chamber (18), and the adjustment system has a measuring device (15). The measuring device (15) is a pressure measuring device (15) arranged in the pressure chamber (19). The pressure in the pressure chamber (19) is determined using the pressure measuring device (15), and the amount of fluid required for the opening process is determined based on the pressure in the pressure chamber (19). A self-discharging separator characterized by this.

2. The control assembly (28) has an injection chamber (8) for the opening fluid. Water, which is a fluid, is supplied to the injection chamber via an opening fluid supply unit (10) to drive the opening movement, and an opening fluid valve (12) is arranged in the opening fluid supply unit (10). The self-discharging separator according to claim 1.

3. The metering element (17) is configured as a piston or a diaphragm. The self-discharging separator according to claim 1 or 2.

4. The pressure chamber (19) has a temperature sensor. The self-discharging separator according to any one of claims 1 to 3.

5. The volume of the pressure chamber (19) is dimensioned such that even when the fluid chamber (18) is filled to maximum, the pressure in the fluid supply line (20) is still higher than the corresponding pressure P in the pressure chamber (19). The self-draining separator according to any one of claims 1 to 4.

6. The self-draining separator according to any one of claims 1 to 5, wherein the fluid chamber (18) is connected between a filling valve (21) and a fluid valve for opening (12).

7. The self-draining separator according to claim 5, wherein an orifice plate is incorporated in the fluid supply line (20).

8. The self-draining separator according to claim 6, wherein an orifice plate is arranged immediately upstream of the filling valve (21).

9. A method for discharging solids in the treatment of a fluid product having a separator according to any one of claims 1 to 8, comprising: a) providing a self-draining separator according to any one of claims 1 to 8, treating the fluid product to be treated, and separating the fluid product into at least a liquid phase and a solid phase; b) opening the filling valve (21), causing the metering element (17) to move towards the pressure chamber (19) due to the inflow of fluid, and increasing the pressure in the pressure chamber (19); c) repeatedly performing measurements in or on the pressure chamber (19) using a measuring device, and comparing the measurement results with a preset value manually or using a control unit, wherein the pressure (P) in the pressure chamber (19) is measured using a pressure measuring device (15), and comparing the measured pressure with a preset pressure as a default value manually or using a control device (24); d) A step of closing the filling valve (21) such that the volume of the released fluid measured is present within the fluid chamber (18) when the measured value corresponds to the default value, wherein the closing of the filling valve (21) is performed when the measured pressure corresponds to a predetermined pressure, and as a result, the measured volume of the released fluid is present within the fluid chamber (18); e) A method comprising opening the release fluid valve (12) and the valve (23) of the compressed air line (22), injecting the measured volume of the release fluid within the fluid chamber (18) into the separator and into the injection chamber (8) for the release fluid via the release fluid supply section (10), thereby moving the piston valve (6) from the closed position to the open position to release the solid matter discharge opening (7) and discharging the solid phase from the centrifuge drum (1).

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