Centrifuge having a centrifugal drum with a cooling device

Abstract

The invention relates to a centrifuge which is designed as a self-emptying separator with a vertical axis of rotation and provided to separate a product P - in particular blood - to be processed into at least two phases in a centrifugal field, of which at least one phase is a liquid phase Lp and another phase is a solid or slurry phase Sp, wherein the separator has at least the following: a rotatable centrifugal drum (1), solid outlet openings (14), an actuatable piston slide (15), wherein an actuation chamber (23) that can be filled with a fluid F is associated with the piston slide (15), and a cooling device for cooling the centrifugal drum, which is implemented in that the fluid F also simultaneously serves to cool the centrifugal drum (1), wherein one or more cooling channels (24) for cooling the centrifugal drum (1) extend(s) from the actuation chamber (23) in the drum casing (1a), which are fluidically connected to the actuation chamber (23) and through which the fluid can additionally flow, wherein at least one of the cooling channels in the drum casing also extends into a region vertically above the piston slide (15), wherein the fluid is conducted through the cooling channels (24) into a peeling disc chamber which rotates with the centrifugal drum (1) and in which the fluid is conducted out of the rotating centrifugal drum (1) through a fluid outlet by means of a peeling disc provided only for this purpose.

Description

[0001] Centrifuge with a centrifugal drum with a cooling device

[0002] The invention relates to a centrifuge according to the preamble of claim 1 and to a method for operating such a centrifuge according to claim 18.

[0003] During the centrifugal processing of various products, especially during the processing of blood, especially human blood, it is imperative that the temperature of the blood is maintained within a precisely defined range throughout the entire separation process in order to ensure product quality.

[0004] Different solutions are known from the state of the art.

[0005] From DE 24 23 319 a centrifuge with a solid bowl design without the possibility of emptying during operation - i.e. during centrifugal processing - is known, which has a cooling device in the centrifuge drum and a cooling device of the housing around the centrifuge drum.

[0006] DE 10 139 466 A1 discloses a centrifuge which is designed as a self-emptying separator, the centrifugal drum of which is not directly cooled, but in which only the area surrounding the centrifugal drum is cooled.

[0007] DE 26 31 110 describes a centrifuge with a self-emptying centrifugal drum, the drum shell of which can be continuously cooled by means of an insert arranged in the solids space of the separation chamber using a circulating cooling medium. The insert is supported at several points in the drum shell and is guided in a sealed manner with respect to the separation chamber of the drum. The coolable insert is conical in shape and has one or more sludge discharge openings along its circumference. The outer sides of the lower insert and the upper insert are provided with helically arranged channels, which are connected to one another by means of connecting channels arranged in ribs with which the lower and upper inserts are connected. The centrifuge thus has a self-emptying centrifugal drum with integrated cooling.

[0008] This technical solution, while advantageous in terms of cooling, has the disadvantage that a multi-part cooling insert is required within the centrifuge drum, which must be sealed to the centrifuge drum by several gaskets. Since sterility in the centrifuge drum is required for many applications, any additional installation within the centrifuge drum should be viewed with skepticism for hygiene reasons. This also applies to the coolant channels, which run in ribs located directly in the separation chamber of the centrifuge drum.

[0009] Furthermore, this design requires two fluids within the centrifuge drum in addition to the product, which usually have to be sealed from each other. First, there is a control fluid for lifting the piston valve and thus closing the solids outlet openings. The second fluid is a cooling fluid that must be fed into the centrifuge drum and the insert, and then out of the centrifuge drum again. Neither fluid must come into contact with the blood being processed, which is a complex design requirement.

[0010] It is further known from DE 1 922 237 C2 that in a self-emptying separator the cooling device is integrated into an opening and closing mechanism of the centrifuge drum that can be actuated with a control fluid, wherein the control fluid is cooled in such a way that it acts as a cooling medium. The control fluid is sterile air, which, compared to water, for example, has a low heat capacity and thus cooling capacity. In this way, the opening and closing mechanism of the centrifuge drum is also used as a cooling device, for which purpose an opening chamber of the opening and closing mechanism is subjected to a first sterile air flow rate during the centrifuge's spinning operation and to a second sterile air flow rate, which is greater than the first flow rate, during the opening of a piston valve. The first flow rate achieves a cooling effect but does not yet move the piston valve.Rather, this shifting is only realized with the second flow rate. The supply channel for the control fluid is structurally connected directly to the inlet pipe for the centrifuge material. Since the control fluid supply line and the centrifuge material supply line are thus routed together into the centrifuge drum and preferably run directly adjacent to each other, a structurally separate supply line for the control fluid can be avoided.

[0011] A centrifuge according to the preamble of claim 1 is also known from SE 456 406 B.

[0012] Although this design is advantageous, it should be further developed with regard to the achievable cooling effect.

[0013] It is therefore desirable to create a self-draining separator with a further optimized cooling device for the centrifugal drum, which also allows the use of a liquid as a cooling medium. The invention aims to solve this problem.

[0014] This object is achieved by the subject matter according to claim 1.

[0015] Accordingly, a centrifuge is created which is designed as a self-emptying separator with a vertical axis of rotation and which is intended to separate a product to be processed - in particular blood - into at least two phases in a centrifugal field, of which at least one phase is a liquid phase and another phase is a solid or sludge phase and has at least the following: a rotatable centrifugal drum with a vertical axis of rotation and a drum shell, solids outlet openings which are circumferentially distributed in the drum shell and which serve to discharge solids from the centrifugal drum, a hydraulically actuated piston slide with which the solids outlet openings can be discontinuously opened and closed again, wherein the piston slide is assigned an actuating chamber which can be filled with a fluid, whereby the piston slide can be actuated, and a cooling device for cooling the centrifugal drum.The cooling device is realized in that the fluid F for actuating the piston slide also serves to cool the centrifugal drum, and in that one or more cooling channels for cooling the centrifugal drum extend / extend from the actuating chamber in the drum shell, which cooling channels are in fluid communication with the actuating chamber and which can additionally be flowed through by the fluid, in particular after flowing through the actuating chamber, wherein one or at least one of the cooling channels in the drum shell also extends into an area vertically above the piston slide.

[0016] The fluid is guided through the cooling channels into a peeling disc chamber rotating with the centrifugal drum, in which the fluid is guided through a fluid outlet from the rotating centrifugal drum by means of a peeling disc provided solely for this purpose.

[0017] It is therefore provided that the fluid for lifting the piston valve - for example, for closing the solids outlet openings for the solid phase with the piston valve - is also used simultaneously to cool the centrifuge drum. Unlike in DE 199 22 237 C2, in which cooling takes place in the area of ​​the inlet pipe and the actuation chamber, the cooling device according to the invention is essentially integrated directly into the drum shell of the centrifuge drum, so that, in comparison to DE 199 22 237 C2, good cooling of the product in the drum can be achieved, in particular also by the drum shell. If reference is made below to a cooling channel, several cooling channels, for example connected in parallel, can also be provided in the drum shell.

[0018] A liquid, especially water, is preferably used as the cooling and actuating fluid. This eliminates the need for a separate cooling device in the area of ​​the drum shell. This is also advantageous because the separation chamber in the centrifuge is designed particularly advantageously in terms of hygiene and cleaning effort.

[0019] In particular, the idea or feature is further developed that the same fluid can be used to cool the centrifuge drum as is used to empty the solids, which leads to a particularly simple structure of the emptying and cooling fluid system of the centrifuge, since only a single circuit for a single fluid needs to be provided.

[0020] This makes it possible, in particular, to achieve greater cooling capacity and greater heat dissipation than with the prior art. The flow of liquid fluid or coolant can be dimensioned and the coolant can be fed into the cooling device at such a temperature that the product temperature can be kept constant or reduced compared to operation without a cooling device. In comparable operation without passing fluid through the cooling device, the product inside the separator drum heats up by typically 2 to 10°C during continuous operation due to the heating of the drum by air friction. The cooling device therefore preferably prevents the drum from heating up due to air friction during centrifuge operation.

[0021] By discharging with the paring disc, the fluid can be easily discharged from the cooling channels under pressure.

[0022] It is also advantageous to conduct the fluid F in an open "circuit" according to one variant, so that, for example, readily available tap water can be used as the fluid, which, for example, has or can have a temperature of approximately 8°C to 12°C directly from the pipe system. This ideally eliminates the need for additional means for pre-cooling the water - such as a refrigeration machine. Furthermore, the water can generally be disposed of without any problems after flowing through the centrifuge's cooling system, for example, by being discharged into the sewer system, since it is generally not further contaminated when flowing through the centrifuge drum.According to an advantageous embodiment, which on the one hand in conjunction with the subject matter of claim 1 advantageously develops this, but which in conjunction with the preamble of claim 1 can also be regarded as an independent invention, for example if the supply of the cooling channels does not take place entirely via the actuating chamber but partly parallel to it, the centrifugal drum has a drum base with a metallic drum base shell and a drum top with a metallic drum top shell, wherein the at least one or one or more of the cooling channels of the cooling device extend both in sections through the drum top shell and in sections through the drum bottom shell.The arrangement of the cooling channels in both the lower drum shell and the upper drum shell ensures particularly effective cooling of the centrifuge drum over a larger area than was previously possible.

[0023] This invention can be implemented particularly advantageously if the actuating chamber is designed as a closing chamber and is formed below the piston slide between the piston slide and the drum lower part, wherein starting from this actuating chamber, the one cooling channel or at least one of the cooling channels initially runs on or through the drum lower part shell and then merges into the drum upper part in a region between the drum lower part shell and the drum upper part shell.

[0024] The actuation chamber is typically designed as a closing chamber, which, when filled with fluid, moves the piston valve vertically to close the solids outlet openings. However, it is also conceivable to design the actuation chamber as an opening chamber, which, when sufficiently filled, moves the piston valve to open the solids discharge openings. Both of these designs are known per se. It is therefore noteworthy that these known designs are also particularly advantageously used according to the invention for the defined cooling of the centrifuge drum shell and thus the separation chamber.

[0025] According to a further preferred embodiment, it is then provided that several of the cooling channels in the centrifugal drum shell are arranged in sections distributed circumferentially, so that a particularly effective and uniform cooling of the drum shell can be achieved.

[0026] In order to simplify the design of the cooling channels, a further preferred embodiment provides for the cooling channels in the centrifugal drum shell to each comprise one or more bores in the centrifugal drum shell. This allows the cooling channels to be integrated into the drum shell particularly easily from a manufacturing perspective.

[0027] The upper and lower sections of the drum are preferably made of metal. They can be formed as metallic parts, particularly forged parts. The holes are then formed directly in these metal parts, which in turn form the centrifugal drum shell.

[0028] This can be implemented in a variety of ways. For example, according to an advantageous embodiment that allows for effective cooling, the holes for the cooling channels can run both in the drum's lower shell and in the drum's upper shell. Furthermore, it can also be provided that at least one of the holes forms one of the fluid outlet openings at one of its ends or opens into one. In this way, the cooling channel system in the drum shell can be easily implemented using a system of holes that is easy to manufacture.

[0029] According to a further advantageous embodiment, in order to achieve a correspondingly good cooling performance, it is provided that at least one of the cooling channels - preferably, of course, several or all of the cooling channels - penetrate the upper part of the drum over more than 50%, in particular more than 70%, of its vertical extent.

[0030] It is advantageous - as it is easy to manufacture - if the holes forming the cooling channels are aligned at an angle to each other.

[0031] In this way, a wide variety of cooling channel designs can be realized. According to one embodiment, one or more of the bores forming the cooling channels in the drum upper shell can extend within the (preferably otherwise conical) drum upper shell into a (preferably cylindrical) drum neck vertically above a separating plate stack, where the respective cooling channel opens into one of the cooling channel outlet openings in this area, through which the fluid F exits the drum upper. This advantageously ensures that the centrifugal drum can be effectively cooled up to the area of ​​the drum neck.

[0032] It can additionally be provided that the paring disc chamber is arranged axially above any paring disc chamber(s) for product phase removal. This, in turn, allows for a good cooling effect over a significant portion of the drum's length, and the fluid can be discharged from the cooling channels under pressure. This variant is also suitable for the implementation of either an open or a closed coolant system or cooling circuit.

[0033] According to a further particularly preferred embodiment of the invention, it can be provided that a collecting channel extending around the centrifuge drum is provided to collect the fluid F emerging from the centrifuge drum, with which the escaping fluid is received during operation of the centrifuge and from which it is discharged through a suitable downstream further channel or a pipe from the hood surrounding the centrifuge drum.

[0034] According to a preferred variant, the cooling device of the separator is designed as a part of a higher-level, in particular closed, cooling fluid circuit, in which the fluid is repeatedly circulated and thus reused. It can then advantageously be provided that the cooling fluid circuit has a heat exchanger, which ensures that the temperature of the fluid F flowing into the cooling channels is controlled or regulated in such a way that the product P to be separated is cooled to the required temperature. This can be controlled and / or regulated by an optional control device.

[0035] Alternatively, the fluid can also be taken from a source such as a water inlet and disposed of after passing through the drum. Even with such a configuration, it may be advantageous to be able to control or regulate the cooling fluid flow, if necessary, using a control device.

[0036] According to a further advantageous embodiment, it can be provided that the cooling fluid supply takes place through a rotary union into a rotating drive spindle and from there into the actuation chamber or that it takes place by spraying water into a radially inwardly open annular channel of the centrifugal drum, which is in fluid connection with the actuation chamber.

[0037] According to a further advantageous embodiment, at least one temperature sensor can additionally be provided, which is coupled to a control device. With this sensor, for example, the temperature in one of the derived product phases or the temperature of the drum shell or a temperature directly in the separation or spinning chamber can be measured. This temperature value can be measured repeatedly and then used as a variable in the control or regulation of the cooling circuit with the aid of the control device and a control and / or regulation computer program. According to a further advantageous embodiment, it can be provided that one or more springs additionally act on the piston slide. For example, it can be provided that a closing force of the fluid in the actuation chamber can be supported by means of additional springs below the piston slide.This ensures that the piston slide remains in the closed position even at low speeds or when the centrifuge drum is at a standstill, if the total force of the springs - which acts as a closing force on the piston slide - is selected to be greater than the opening force acting on the piston slide by the product at low drum speeds.

[0038] With such a design, the centrifuge drum can be brought to a standstill without opening the solids outlets. Before restarting the centrifuge, it is then possible to extract the remaining liquid phase from the stationary centrifuge drum.

[0039] The invention also provides a method for operating a centrifuge according to one of the claims relating to the centrifuge. This method may comprise the following method steps: a) providing the operating centrifuge and the fluid F, and b) continuously conveying the fluid cooled to a defined temperature through the actuation chamber and the one or more cooling channels in the drum shell—at a defined volume flow, particularly between solids discharges.

[0040] In this way, a continued cooling of the centrifugal drum, which is designed particularly advantageously for this purpose, is achieved in a simple manner, particularly in the area of ​​its drum shell.

[0041] According to an advantageous variant of this method, it can be provided that during step b) the fluid cooled to a defined temperature is first conveyed through the actuation chamber and only then is the fluid conveyed through the one or more cooling channels with a defined volume flow.

[0042] For controlling or regulating the cooling, it is advantageous if temperature readings are repeatedly measured during process step b), particularly in the centrifuge drum or in the product outlet, or at another suitable location. According to an advantageous variant, the fluid is conducted in an open circuit. However, it can also be conducted in a closed fluid circuit.

[0043] In an advantageous embodiment of the method, it can be provided that a fluid pressure is generated by a pump and / or that a required volume flow is set by a valve with which the fluid F flows through the cooling channels, wherein a required control signal for this purpose is generated by the control device.

[0044] In an advantageous embodiment of the method, it can then be provided that the temperature of the fluid flowing into the cooling channels is cooled to a defined temperature value with the aid of a heat exchanger.

[0045] In a further advantageous embodiment of the method, it can then be provided that the cooling fluid supply takes place through a rotary union in a drive spindle or by spraying water into a radially inwardly open annular channel of the centrifugal drum, which is in fluid communication with the actuation chamber.

[0046] It is particularly advantageous if the control device is used to control or regulate the coolant flow in order to achieve a temperature setpoint, for example at the measuring point at which the temperature sensor is arranged.

[0047] Further advantageous embodiments of the invention can be found in the remaining subclaims.

[0048] The invention is described in more detail below with reference to the drawings.

[0049] It shows:

[0050] Figure 1: a view of a centrifuge in full section with raised piston slide and closed outlet openings;

[0051] Figure 2: a view of the centrifuge from Fig. 1 in full section with raised

[0052] Piston valve in the right half of the illustration and lowered piston valve in the left half of the illustration;

[0053] Figure 3: an enlarged detail of Fig. 1 ; Figure 4: a view in full section of a variant of the centrifuge from

[0054] Fig. 1 ;

[0055] Figure 5: the centrifuge from Fig. 4 with a closed fluid circuit;

[0056] Figure 6: a view in full section of a variant of the centrifuge from

[0057] Fig. 1 with raised piston valve and closed outlet openings;

[0058] Figure 7: a schematic view in full section through a self-emptying

[0059] State-of-the-art separator.

[0060] The following description of the figures describes various exemplary embodiments. Individual features of these exemplary embodiments can also be combined with exemplary embodiments not shown and are also suitable as advantageous embodiments of the subject matter described in one or more of the main and subordinate claims.

[0061] Fig. 7 shows a centrifuge designed as a self-emptying separator for the continuous processing of a product. The centrifugal drum has a vertical axis of rotation. In addition to a centrifugal drum 1, the separator also includes other components—not shown in their entirety here—such as a control computer, a drive motor for rotating the centrifugal drum 1, a hood 2, a solids catcher 3, etc. During centrifugal processing of the product, it is separated into several product phases, which may include at least one liquid phase or several liquid phases and at least one solid phase.

[0062] In the context of this document, a solid phase is also understood to mean a sludge phase, as a mixture of solids and a small amount of liquid.

[0063] A drive motor (not shown here) is provided to drive the rotatable centrifugal drum 1. This is preferably done via a driven, rotatably mounted drive spindle 4, which is arranged vertically here and thus has a vertically oriented axis of rotation D. The centrifugal drum 1 is preferably—but not necessarily—designed for continuous operation—i.e., the continuous and not batchwise processing of a product P in the centrifugal field.

[0064] The centrifugal drum 1 here comprises a drum base 5 with a drum base shell 5a, and a drum top 6 with a drum top shell 6a. The drum base shell 5a and the drum top shell 6a together form a drum shell 1a. The drum top 6 and the drum base 5 are preferably made of metal. They can, for example, be formed as metal forgings.

[0065] In the single- or double-conical centrifugal drum 1, a stack of separating plates 8 consisting of conical separating plates 9 can be arranged in the drum interior 7—which is also synonymously called the centrifugal chamber. The separating plates 9 are then usually arranged on a distributor shaft 10 of a distributor 11.

[0066] An inlet pipe 12 serves to supply a suspension or product P to be processed. The inlet pipe 12 is designed here as a stationary element that does not rotate during operation (although it could alternatively be designed to rotate). It extends concentrically to the rotational axis D into the centrifuge drum 1. According to Fig. 7, in a preferred—but not mandatory—configuration, it projects from above into the centrifuge drum 1. However, it can also extend from below into the centrifuge drum 1.

[0067] The flowable product P to be processed—here preferably human blood—is fed into the centrifuge drum 1 through the inlet pipe 12. The product P exiting the free end of the inlet pipe 12 flows into radially extending distribution channels 13 of the distributor 11 and is rotated or accelerated in the circumferential direction as a result of the rotation of the rotating centrifuge drum 1. The distribution channels 13 open into the drum interior 7 with the plate stack 8.

[0068] In the drum interior 7—also called the centrifugal chamber—the product P to be processed is separated into at least two phases of different densities in a centrifugal field, at least one of which is a liquid phase Lp. In the example in Fig. 7, the product P is separated into a solid or sludge phase Sp and two liquid phases Lp1, Lp2 of different densities. Alternatively, the product P can be clarified into a solid phase Sp and only one liquid phase Lp, or into more than two liquid phases Lp.

[0069] The solids Sp are ejected outwards from the centrifugal drum 1 through circumferentially distributed, radially extending solids outlet openings 14 - preferably in the region of the largest radius / circumference of the centrifugal drum 1.

[0070] The solids outlet openings 14 can be nozzle-like. They are assigned an opening and closing mechanism. As shown by way of example in Fig. 7, this has a hydraulically actuated piston slide 15 arranged in the lower drum section 5, with which the solids outlet openings 14 can be discontinuously opened and closed again. For this purpose, fluid is fed into an actuation chamber 23 below the piston slide 15. The fluid F required for this purpose - e.g. water - is fed under the piston slide 15 by means of valves (not shown here) to close the solids outlet openings 14, in order to move it under the action of the lifting forces generated during the rotation of the drum, and can also be drained from there again to open the solids outlet openings 14.Alternatively, the fluid F can also be supplied through a rotary guide in lines in the rotating drive spindle 4 and further through a feedthrough (not shown here) into the centrifugal drum 1.

[0071] The piston slide 15 is shown open in the left half of the illustration in Fig. 7 and closed in the right half of the illustration in Fig. 7.

[0072] According to Fig. 7, two liquid outlets 16a, b are provided by way of example. The lighter first liquid phase Lp1 flowing radially inwards from the plate stack 8 flows into a first paring disc chamber 17 which rotates with the centrifugal drum 1. A first paring disc 18 - also referred to as a gripper - is arranged in the first paring disc chamber 17. This first paring disc 18 is arranged stationary in the first paring disc chamber 17, e.g. non-rotatably on the inlet pipe 12. The first paring disc 18 is provided to discharge the lighter, first liquid phase Lp1 from the centrifugal drum 1, so that the lighter, first liquid phase Lp1 leaves the centrifugal drum 1 via the first liquid outlet 16a.

[0073] The heavier second liquid phase Lp2, which flows radially further outward from the plate stack 8, flows into a second impeller disc chamber 19, which also rotates with the centrifuge drum 1. A second impeller disc 20 is arranged in the second impeller disc chamber 19. This second impeller disc 20 is also arranged stationary in the second impeller disc chamber 19. The second impeller disc 20 is provided to discharge the heavier, second liquid phase Lp2 from the centrifuge drum 1, so that the heavier, second liquid phase Lp2 leaves the centrifuge drum 1 via the second liquid outlet 16b.

[0074] Temperature sensors can be provided in the liquid outlets 16a and / or 16b, which transmit temperature measurements of the liquid phases to the control device. The paring discs 18, 20 each operate according to the principle of a centripetal pump.

[0075] It is intended that the fluid F is used to lift the piston valve 15 - i.e. to close the solids outlet openings 14 for the solids or sludge phase Sp

[0076] - is also used at the same time to cool the centrifugal drum 1 (see Fig. 1 ).

[0077] For this purpose, a fluid F can be brought to the required temperature for cooling the centrifugal drum 1 using suitable means before it is fed into the centrifugal drum 1. As with self-emptying separators known from the prior art, the fluid F is continuously sprayed, for example radially from the inside to the outside, into an open collecting chamber 21 of the rotating centrifugal drum 1 through stationary nozzles (not shown here) which do not rotate with the drum during operation and from there is fed through channels 22 into an actuating chamber 23 below the piston slide 15, as is shown by way of example in Fig. 1. The actuating chamber 23 is designed here as a closing chamber. The supply principle shown in Fig. 1 is also referred to as an “open supply system”. This supply principle is particularly simple to implement in terms of construction. However, it does not have to be used.

[0078] Because according to an alternative design, the fluid F can also be

[0079] - for example, through a rotary union (not shown here) into channels within the drive spindle 4 and from there into the closing chamber 23. This supply principle can also be referred to as a closed supply system.

[0080] When the actuation chamber 23 is filled, the piston valve 15 rises and closes the solids outlet openings 14 for the solids or sludge phase Sp on the outer circumference of the centrifuge drum 1. To lower the piston valve 15 and thus open the solids outlet openings 14, the fluid supply to the actuation chamber is interrupted. Since some of the fluid continues to escape from the actuation chamber 23 through the channels 24, the piston valve is pushed downward by the product P in the drum interior 7.

[0081] One or more features of the prior art are also realized in the embodiments according to the invention.

[0082] It is then provided according to an exemplary embodiment - see Fig. 1 - that cooling channels 24 distributed over the circumference of the centrifugal drum 1 extend both in the drum lower part shell 5a and in the drum upper part shell 6a for cooling the centrifugal drum 1, as is shown by way of example in Fig. 1.

[0083] In this respect, the actuating chamber 23 is in fluid communication with the cooling channels 24 in the drum lower part shell 5a and in the drum upper part shell 6a.

[0084] The cooling channels 24 are preferably implemented in a simple manner by means of holes in the metallic drum shell 1a. This can be achieved in various ways. Some preferred configurations are described below, but these can be varied by those skilled in the art. This allows them to determine a particularly advantageous layout for the cooling channels in the drum shell through testing and / or calculation.

[0085] 1 - 6, for example, first, here vertical bores 24a are arranged circumferentially distributed in the drum lower part shell 5a between the outlet openings 14, one end of these vertical bores 24a being in fluid communication with the actuation chamber 23 and the other end of these first vertical bores 24a being in fluid communication with further bores 24b, 24c, 24d, 24e running in the drum upper part shell 6a, which together each form one of the cooling channels 24.

[0086] A respective second bore 24b extends essentially horizontally in the drum upper shell 6a and is in fluid communication with the respective bore 24a in the drum lower shell 5a. Adjacent to the respective second, here horizontal bore 24b is a third bore 24c, which runs essentially parallel to an internal geometry of the drum upper shell 6a, which is conical both inside and out. Adjacent to the respective third bore 24c is a fourth bore 24d, which also runs essentially parallel to the internal geometry of the drum upper shell 6a. Adjacent to the respective fourth bore 24d is a vertically extending fifth bore 24e. These bores 24b, 24c, 24d, 24e, which form the respective cooling channel 24 in the drum upper shell 6a, run within the drum upper shell 6a to a drum neck 25 above the separating plate stack 8.The term “drum neck” 25 refers here to the axially upper end of the drum upper part 6 or the drum upper part shell 6a.

[0087] The respective cooling channel 24 ends there at a cooling channel outlet opening 26, through which the fluid F—a liquid, for example, water—exits radially outward from the upper drum section 6. During operation of the centrifuge, the escaping fluid F is collected by a collecting trough 27 extending around the centrifuge drum 1 and discharged from the hood 2 through a pipe or a channel.

[0088] In one embodiment, the fluid F can be guided through the cooling channels 24 into a third paring disc chamber 28 which rotates with the centrifuge drum 1, in which third paring disc chamber the fluid F is then guided out of the rotating centrifuge drum 1 through a fluid outlet 35 by means of a third paring disc 29 which is stationary during operation of the centrifuge and operates according to the principle of a centripetal pump, as is shown purely by way of example in Fig. 4 and Fig. 5. The third paring disc chamber 28 and thus the third paring disc 29 are arranged axially above the second paring disc chamber 19 and the second paring disc 20. The discharge of the fluid F through the third paring disc 29 has the advantage that the discharge of the fluid F from the drum shell 1a takes place in a closed manner and under pressure.

[0089] The position and course of the cooling channels 24 and thus the position of the bores 24a, 24b, 24c, 24d, 24e can also be designed differently than shown in Figures 1, 2, 6. An alternative is shown, for example, in Figures 4 and 5. Here, the fifth bore 24e of the respective cooling channel 24 passes through almost the entire drum neck 25 in the axial direction, finally opening into the third paring disc chamber 28 via the cooling channel outlet opening 26, which is directed radially inward here. It is essential that the cooling channels 24 are arranged within the drum lower part shell 5a and within the drum upper part shell 6a.

[0090] To keep the piston valve 15 raised and the solids outlet openings 14 closed, fluid F must be continuously supplied to the actuation chamber 23 of the centrifuge drum 1 and keep it filled, while simultaneously flowing fluid F from the actuation chamber 23 into the cooling channels 24. This continuous flow of fluid F through the cooling channels 24 also ensures constant cooling of the centrifuge drum 1.

[0091] This ensures that the same fluid F is used to both keep the centrifuge drum 1 closed and to cool the centrifuge drum 1.

[0092] Contamination of the solid or sludge phase Sp emptied from the centrifuge drum 1 by the fluid F also emerging from the centrifuge drum 1 is structurally avoided by the arrangement of the collecting trough 27 and the solid catcher 3 spaced vertically one above the other, as shown by way of example in Fig. 3. A particularly good separation between the fluid F and the solid or sludge phase Sp is achieved by a closed discharge of the fluid F from the centrifuge drum 1 according to the embodiment of the centrifuge shown in Fig. 4 or Fig. 5.

[0093] 1, 2 and 3 and 6, in which the fluid F is guided in an “open circuit”, the fluid F can be guided in a closed fluid circuit FC, as is shown purely by way of example in Fig. 5, wherein the required fluid pressure can be generated with a pump 30. The required volume flow with which the fluid F flows through the cooling channels 24 can be set with a valve 31, wherein a required control signal for this is generated by a control device 32. Alternatively, a controlled pump can be provided with which the volume flow of the fluid F can be regulated. In such a case, the valve 31 can be omitted.

[0094] In the fluid circuit FC, a suitable heat exchanger 33 can also be used to ensure that the temperature of the fluid F flowing into the cooling channels 24 is regulated such that the product to be separated - in this case human blood - is cooled to the required temperature. This can also be regulated and / or monitored by the control device 32, for example by detecting the fluid temperature in the inlet and / or outlet of the heat exchanger using sensors. The temperature of the product phase Lp1 and / or Lp2 (not shown) can also be detected using suitable sensors. These measured temperature values ​​are passed on to the control device and evaluated in order to implement a suitable control system that ensures compliance with the required product temperature in the drum.

[0095] An additional buffer tank with a fluid inlet (not shown here) can be provided in the fluid circuit FC to compensate for any fluid losses in the fluid circuit FC. For this purpose, the buffer tank can be equipped with a fill level sensor connected to the control device 32, which opens a valve in the fluid inlet of the buffer tank when the fill level falls below a certain level and closes this valve again when the limit is exceeded.

[0096] In a further embodiment of the separator according to the invention, the centrifugal drum 1 is emptied in the following way: When the centrifugal drum rotates at an operating speed of, for example, more than 3000 rpm, the inflow of fluid F is interrupted, for example by valve 31 (see Fig. 5), which is controlled by control device 32 (also see Fig. 5), so that part of the fluid F flows from the actuating chamber 23 through the cooling channels 24 and exits into the collecting trough 27, and the actuating chamber 23 is no longer completely filled. The closing force exerted on the piston slide 15 by the remaining fluid F in the actuating chamber 23 is then lower than the force exerted on the piston slide 15 by the product P located in the centrifugal drum 1.This pushes the piston valve 15 downward, thereby opening the solids outlet openings 14, as shown by way of example on the left side of Fig. 2. The centrifugally separated sludge or solid phase Sp can be expelled. As soon as the fluid F is fed back into the actuation chamber 23 of the centrifugal drum 1 and fills it, the piston valve 15 rises again and closes the solids outlet openings 14.

[0097] In one embodiment of the separator according to Fig. 6, the closing force of the fluid F in the actuating chamber 23 can be supported by additional springs 34, which are provided below the piston slide 15 between the latter and the lower part of the drum and which can push this piston slide 15 vertically upward. This ensures that the piston slide 15 remains in the closed position even at low speeds or when the centrifugal drum 1 is at a standstill, if the total force of the springs 34—which acts as a closing force on the piston slide 15—is selected to be greater than the opening force acting on the piston slide 15 due to the product P at low drum speeds.

[0098] With such a configuration, the centrifuge drum 1 can be brought to a standstill without the solids outlet openings 14 of the centrifuge drum 1 opening. Before the centrifuge is restarted, it is then possible to suction off the remaining liquid phase from the stationary centrifuge drum 1.

[0099] Alternatively, the centrifuge drum 1 can be accelerated again after coming to a standstill without fluid F in the actuation chamber 23. The piston slide 15 is then pushed into its open position at a specific speed. This occurs due to the pressure that occurs when the product P remaining in the drum interior 7 is pressed against the piston slide 15 by centrifugal force. In this way, the centrifuge drum 1 can be emptied before it is accelerated to operating speed for a further separation process. Before the centrifuge drum 1 is again fed with product P, the fluid F is directed into the actuation chamber 23 and the cooling channels 24 to actuate the piston slide 15 and to cool the centrifuge drum 1, so that the piston slide 15 is raised and the outlet openings 14 are closed.In this way, a centrifuge, in particular a separator for processing human blood, is provided in which the cooling device of the centrifugal drum 1 is not located in the drum interior 7 but in the drum lower part shell 5a and in the drum upper part shell 6a and thus does not require any special cleaning.

[0100] The following procedure is specified for the operation of a centrifuge according to the invention:

[0101] In a first process step, the centrifuge in operation - in particular at an operating speed - and the fluid F brought to a defined temperature are provided.

[0102] In a second process step, the fluid F cooled to a defined temperature is conveyed through the one or more cooling channels 24 - in particular between solid discharges - with a defined volume flow.

[0103] During the second process step, the temperature in the centrifuge drum 1 is measured. It is then possible to increase or decrease the flow rate of cooling fluid in a controlled or repeatedly regulated manner in order to adjust the temperature to a setpoint.

[0104] List of reference symbols

[0105] 1 centrifugal drum

[0106] 1a drum shell

[0107] 2 hood

[0108] 3 solids traps

[0109] 4 drive spindle

[0110] 5 Drum base

[0111] 5a Drum base shell

[0112] 6 Drum top

[0113] 6a Drum shell

[0114] 7 Drum interior

[0115] 8 stacks of separating plates

[0116] 9 separating plates

[0117] 10 Distribution shaft

[0118] 11 distributors

[0119] 12 Inlet pipe

[0120] 13 Distribution channel

[0121] 14 Exit opening

[0122] 15 piston valves

[0123] 16a, b Fluid drain

[0124] 17 first peeling disc chamber

[0125] 18 first peeling disc

[0126] 19 second peeling disc chamber

[0127] 20 second peeling disc

[0128] 21 Catch chamber

[0129] 22 channels

[0130] 23 Actuating chamber

[0131] 24 cooling channel

[0132] 24a, b, c, d, e bore

[0133] 25 Drum neck

[0134] 26 Cooling channel outlet opening

[0135] 27 drip tray

[0136] 28 third peeling disc chamber

[0137] 29 third peeling disc

[0138] 30 pump

[0139] 31 Valve

[0140] 32 Control device

[0141] 33 Heat exchanger 34 Spring

[0142] 35 Fluid drain

[0143] D axis of rotation

[0144] P Product Lp1 , Lp2 Liquid phase

[0145] Sp solid phase

[0146] F Fluid

[0147] FC fluid circuit

Claims

Claims 1 . Centrifuge which is designed as a self-emptying separator with a vertical axis of rotation and which is intended to separate a product P to be processed - in particular blood - into at least two phases in a centrifugal field, of which at least one phase is a liquid phase Lp and another phase is a solid or sludge phase Sp, wherein the separator has at least the following: a) a rotatable centrifugal drum (1) with a vertical axis of rotation D and a drum shell (1a), b) solids outlet openings (14) which are circumferentially distributed in the drum shell (1a) and which serve to discharge solids Sp from the centrifugal drum (1), c) a piston slide (15) which is hydraulically actuated by means of a fluid and with which the solids outlet openings (14) can be discontinuously opened and closed again, d) wherein the piston slide (15) has an actuating chamber which can be filled with a fluid F (23) is assigned,e) a cooling device for cooling the centrifugal drum, which is realized in that the fluid F for actuating the piston slide (15) also simultaneously serves to cool the centrifugal drum (1), f) wherein, starting from the actuation chamber (23), one or more cooling channels (24) for cooling the centrifugal drum (1) extend(s) in the drum shell (1a), which are in fluid communication with the actuation chamber (23) and which can additionally be flowed through by the fluid - in particular after flowing through the actuation chamber, and wherein g) one or at least one of the cooling channels in the drum shell also extends into a region vertically above the piston slide (15), characterized in that h) the fluid is guided through the cooling channels (24) into a peeling disc chamber rotating with the centrifugal drum (1),in which the fluid is guided through a fluid outlet from the rotating centrifugal drum (1) by means of a paring disc provided solely for this purpose.

2. Centrifuge according to claim 1 or according to the preamble of claim 1, characterized in that the centrifugal drum (1) has a drum base (5) with a metallic drum base shell (5a) and a drum top (6) with a metallic drum upper part shell (6a), wherein the at least one or one or more of the cooling channels (24) of the cooling device extend both in sections through the metallic drum upper part shell (6a) and in sections through the metallic drum lower part shell (5a).

3. Centrifuge according to claim 1 or 2, characterized in that the fluid is a liquid, in particular water.

4. Centrifuge according to one of the preceding claims, characterized in that the actuating chamber (23) is designed as a closing chamber and is formed below the piston slide (15) between the piston slide (15) and the lower drum part (5), and that starting from this actuating chamber (23) one or at least one of the cooling channels (24) initially runs on or through the lower drum part shell (5a) and then merges into the upper drum part (6) in a region between the lower drum part shell (5a) and the upper drum part shell (6a).

5. Centrifuge according to one of the preceding claims, characterized in that several of the cooling channels (24) are arranged circumferentially distributed in the centrifugal drum shell (1 a).

6. Centrifuge according to claim 5, characterized in that the circumferentially distributed cooling channels (24) are each carried vertically or substantially vertically between two of the solids discharge openings.

7. Centrifuge according to one of the preceding claims, characterized in that the cooling channel(s) (24) in the centrifugal drum shell (1 a) each have one or more bores (24a, 24b, 24c, 24d, 24e) in the centrifugal drum shell (1 a).

8. Centrifuge according to claim 7, characterized in that the bores of the cooling channels (24) run both in the lower drum part shell (5a) and in the upper drum part shell (6a), and that at least one of the bores forms one of the fluid outlet openings at one of its ends or opens into such an opening.

9. Centrifuge according to one of the preceding claims, characterized in that at least one or more of the cooling channels penetrate the upper part of the drum over more than 50%, in particular more than 70%, of its vertical extent.

10. Centrifuge according to one of the preceding claims, characterized in that the bores forming the cooling channels (24) are each aligned at an angle to one another.

11. Centrifuge according to one of the preceding claims, characterized in that one or more of the bores (24b, 24c, 24d, 24e) forming the cooling channels (24) in the upper drum part shell (6a) extend within the upper drum part shell (6a) into a drum neck (25) vertically above a separating plate stack (8), where the respective cooling channel (24) opens in this region into one of the cooling channel outlet openings through which the fluid F exits the upper drum part (6).

12. Centrifuge according to one of the preceding claims, characterized in that the paring disc chamber is formed axially above any paring disc chamber(s) for product phase discharge.

13. Centrifuge according to one of the preceding claims 1 to 11, characterized in that the cooling device of the separator is designed as part of a higher-level cooling fluid circuit which has a heat exchanger, wherein the flow of the fluid can be controlled and / or regulated by a control device.

14. Centrifuge according to one of the preceding claims, characterized in that the fluid can be taken from a source such as a water inlet and is disposed of after passing through the drum, wherein the fluid supply can be controlled or regulated by a control device.

15. Centrifuge according to one of the preceding claims, characterized in that the fluid supply takes place through a rotary union in a drive spindle or by spraying water into a radially inwardly open annular channel of the centrifugal drum, which is in fluid communication with the actuating chamber (23).

16. Centrifuge according to one of the preceding claims, characterized in that a temperature sensor is provided which is coupled to the control device.

17. Centrifuge according to one of the preceding claims, characterized in that one or more springs additionally act on the piston slide.

18. Method for cooling a centrifuge according to one of the preceding claims during the centrifugal processing of a product, characterized by the following method steps: a) providing the centrifuge in operation and the fluid F and b) continued conveying of the fluid cooled to a defined temperature through the actuating chamber and the one or more cooling channels (24) in the drum shell with a defined volume flow, in particular between solids discharges.

19. The method according to claim 18, characterized in that during step b) the fluid cooled to a defined temperature is first conveyed through the actuating chamber (23) and only then is the fluid conveyed through the one or more cooling channels (24) with a defined volume flow.

20. Method according to one of the preceding method claims, characterized in that temperature measurement values are repeatedly recorded during method step b). 21 . Method according to one of the preceding method claims, characterized in that during method step b) temperature measurement values are measured in the centrifugal drum (1) and / or the product phase Lp1 and / or Lp2 in one or both liquid outlets.

22. Method according to one of the preceding method claims, characterized in that the fluid F is conducted in an open circuit.

23. Method according to one of the preceding method claims, characterized in that the fluid F is guided in a closed fluid circuit FC.

24. Method according to one of the preceding method claims, characterized in that a fluid pressure is generated by a pump (30).

25. Method according to one of the preceding method claims, characterized in that the required volume flow with which the fluid F flows through the cooling channels (24) is set by means of a valve (31), a required control signal for this being generated by the control device (32).

26. Method according to one of the preceding method claims, characterized in that the temperature of the fluid F flowing into the cooling channels (24) is cooled to a defined temperature value with the aid of a heat exchanger (33).

27. Method according to one of the preceding method claims, characterized in that the cooling fluid supply takes place through a rotary union in a drive spindle or by spraying water into a radially inwardly open annular channel of the centrifugal drum, which is in fluid communication with the actuating chamber (23).

28. Method according to one of the preceding method claims, characterized in that the control device controls or regulates the coolant supply or a coolant flow in order to achieve a temperature setpoint.

29. Method according to one of the preceding method claims, characterized in that an additional buffer tank with a fluid inlet is provided in the fluid circuit FC, wherein the buffer tank is equipped with a fill level sensor which is connected to the control device (32), which opens a valve in the fluid inlet when a fill level is undershot and closes the valve again when the limit value is exceeded.

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