Centrifuge with a centrifugal drum with a cooling device

Abstract

A centrifuge designed as a self-emptying separator with a vertical axis of rotation and 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 comprises at least the following: a rotatable centrifugal drum (1), solids outlet openings (14), an actuatable piston slide (15), wherein the piston slide (15) is assigned an actuation chamber (23) fillable with a fluid F, a cooling device for cooling the centrifugal drum, which is realized in that the fluid F also simultaneously serves to cool the centrifugal drum (1), 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 actuating chamber (23) and which can additionally be flowed through by the fluid, wherein at least one of the cooling channels in the drum shell also extends into a region vertically above the piston slide (15).

Description

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 20.In the centrifugal processing of various products, in particular in the processing of blood, in particular human blood, it is absolutely necessary for the temperature of the blood to be kept within a precisely defined range during the entire separation process in order to ensure product quality.For this purpose, different solutions are known from the prior art.DE 24 23 319 discloses a centrifuge with a solid shell design without any emptying possibility during operation, i.e. during centrifugal processing, which has a cooling device in the centrifugal drum and a cooling device of the housing around the centrifugal drum.DE 10 139 466 A1 discloses a centrifuge which is designed as a self-emptying separator whose centrifugal drum is not cooled directly, but in which only the environment of the centrifugal drum is cooled.DE 26 31 110 describes a centrifuge with a self-emptying centrifugal drum, the drum shell of which can be continuously cooled by a circulating cooling medium by means of an insert arranged in the solids space of the separation space, the insert being supported at a plurality of points in the drum shell and being guided in a sealing manner with respect to the separation space of the drum. The coolable insert is tapered and has one or more slurry discharge openings along its periphery. The outer sides of the lower insert and the upper insert are provided with helically arranged channels which are connected to each other by means of connecting channels arranged in ribs by which the lower and upper inserts are connected to each other. The centrifuge thus has a self-emptying centrifugal drum with integrated cooling.This technical solution, which is advantageous per se with regard to the cooling effect, has the disadvantage that a multipart insert is required for the cooling within the centrifugal drum, which insert has to be sealed off from the centrifugal drum by a plurality of seals. Since sterility is required in the spinner drum in many applications, any additional installation in the spinner drum is critical for reasons of hygiene. This also applies to the coolant channels which run in ribs which are located directly in the separating space of the centrifugal drum.Furthermore, in this construction, two fluids are required inside the centrifugal drum in addition to the product, which fluids are usually to be sealed with respect to one another. On the one hand, this is a control fluid for lifting the piston slide and thus for closing the solids outlet openings. On the other hand, this is a cooling fluid which has to be conducted into the centrifugal drum and into the insert and also has to be conducted out of the centrifugal drum again. Both fluids must not come into contact with the blood to be processed, which is only complicated to implement.It is also 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 centrifugal drum which 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 has a low heat capacity and thus cooling capacity compared, for example, with water. In this way, the opening and closing mechanism of the centrifugal 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 centrifugal operation of the centrifuge and to a second sterile air flow rate during an opening of a piston slide, which is greater than the first flow rate. The first flow rate achieves a cooling effect, but does not yet displace the piston slide. Rather, this displacement is only realized at the second flow rate. Structurally, the feed channel for the control fluid is directly assigned to the inlet pipe for the centrifugal material. Since the control fluid supply line and the centrifugal material supply line are thus guided together into the centrifugal drum and preferably also run directly next to one another, a structurally separate supply line of the control fluid can be avoided.This construction is advantageous, but it is intended to be developed further with regard to the cooling effect which can be achieved.It is thus desirable to create a self-emptying separator with a further optimized cooling device for the centrifugal drum, wherein a liquid should also be usable as a cooling medium.The invention has as its object to solve this problem.This object is achieved with the subject matter according to claim 1.Accordingly, a centrifuge is provided which is designed as a self-emptying separator with a vertical axis of rotation and which is provided for separating a product to be processed, in particular blood, in a centrifugal field into at least two phases, 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, solid outlet openings which are designed in a circumferential manner in the drum shell and which serve for the outlet of solids from the centrifugal drum, a hydraulically actuatable piston slide with which the solid outlet openings can be opened and closed again discontinuously, wherein an actuation chamber which can be filled with a fluid is associated with the piston slide, as a result of which 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 for cooling the centrifugal drum, and that, starting from the actuating chamber, one or more cooling channels for cooling the centrifugal drum extend / extend in the drum jacket, which are in fluid connection with the actuating chamber and which can additionally be flowed through by the fluid, in particular following a flow through the actuating chamber, wherein the one or at least one of the cooling channels in the drum jacket also extends as far as a region vertically above the piston slide.It is thus provided that the fluid for lifting the piston slide-i.e. for example for closing the solid outlet openings for the solid phase with the piston slide-is also simultaneously used for cooling the centrifugal drum. Unlike in DE 199 22 237 C2, in which the cooling takes place in the region of the inlet pipe and the actuation chamber, the cooling device according to the invention is rather substantially integrated directly into the drum shell of the centrifugal drum, so that good cooling of the product in the drum, in particular also by the drum shell, can be achieved in comparison with DE 199 22 237 C2. If a cooling channel is referred to below, a plurality of cooling channels, for example parallel-connected, can also be provided in the drum shell.In this case, a liquid, in particular water, is preferably used as the cooling and actuating fluid. In this way, in particular, the need for a separate cooling device in the region of the drum jacket is dispensed with. This is also advantageous since the separation space in the centrifuge is thus also particularly advantageous with regard to hygiene and with regard to the cleaning effort.According to the invention, the idea or the feature is also developed in particular advantageously that the same fluid as for emptying the solids can be used or is used for cooling the centrifugal drum, which leads to a particularly simple structure of the emptying and cooling fluid system of the centrifuge, since only a single circuit has to be provided for a single fluid.In this way, it is also possible in particular to achieve a greater cooling capacity or a greater heat removal than in the prior art. Thus, the coolant flow of liquid fluid or coolant can be dimensioned such and the coolant can be conducted into the cooling device at such a temperature that the temperature of the product can be kept constant or reduced compared to operation without a cooling device. In a comparable operation without passing fluid through the cooling device, the product in the interior of the separator drum in continuous operation usually heats up by 2 to 10° C. due to the heating of the drum by the air friction.According to an advantageous variant of the invention, it can further be provided that at least one or more cooling channel outlet opening(s) is / are provided in the drum shell of the centrifugal drum, through which the fluid F exits the centrifugal drum radially outwards. This is simple in construction and advantageous in terms of process engineering.It is also advantageous to conduct the fluid F in an open "circuit", so that, for example, easily available tap water can be used as the fluid, which, for example, has or can have a temperature of about 8° C. to 12° C. directly out of the line system, so that in the ideal case additional means for precooling the water-for example a refrigerating machine-can be dispensed with. In addition, the water can generally be disposed of completely without problems after flowing through the cooling device of the centrifuge, for example introduced into the sewer system, since it is generally no longer contaminated when flowing through the centrifugal drum.According to an advantageous embodiment which, on the one hand, in conjunction with the subject matter of claim 1 advantageously develops the latter, but which, in conjunction with the preamble of claim 1, can also be considered as an independent invention, for example, if the supply of the cooling channels is not effected completely via the actuating chamber but partially parallel thereto, the centrifugal drum has a drum lower part with a metallic drum lower part jacket and a drum upper part with a metallic drum upper part jacket, wherein the at least one or one or more of the cooling channels of the cooling device extend both in sections through the drum upper part jacket and in sections through the drum lower part jacket. By the arrangement of the cooling channels both in the lower drum part jacket and in the upper drum part jacket, a particularly effective cooling of the centrifugal drum is ensured over a larger region than was provided according to the prior art.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 lower drum part, wherein, starting from this actuating chamber, the one cooling duct or at least one of the cooling ducts initially runs on or through the lower drum part jacket and then merges into the upper drum part in a region between the lower drum part jacket and the upper drum part jacket.The actuating chamber is generally designed as a closing chamber which, when filled with fluid, moves the piston slide vertically in such a way that it closes the solids outlet openings. However, it is also conceivable to design the actuating chamber as an opening chamber which, when sufficiently filled, moves the piston slide in such a way that it opens the solids discharge openings. Both of these designs are known per se. In this respect, it is noteworthy that these designs known per se are also used according to the invention particularly advantageously for defined cooling of the centrifugal drum jacket and thus of the separation chamber.According to a further preferred embodiment, it is then provided that a plurality of the cooling channels in the centrifugal drum jacket are arranged in any case in sections in a circumferentially distributed manner, so that particularly effective and uniform cooling of the drum jacket can be achieved.In order to implement the cooling channels in a structurally simple manner, it is provided according to a further preferred embodiment that the cooling channels in the centrifugal drum jacket each comprise one or more bores in the centrifugal drum jacket. This is because the cooling channels can be integrated into the drum shell particularly easily from a manufacturing standpoint.The upper drum part and the lower drum part preferably consist of metal. They can be designed, for example, as metallic parts, in particular as forged parts. The bores are then formed directly in these metal parts, which in turn form the centrifugal drum jacket.This can be implemented in a wide variety of ways. Thus, according to an advantageous embodiment with which good cooling can be realized, the bores of the cooling channels can run both in the lower drum part jacket and in the upper drum part jacket. It can furthermore also be provided that in each case at least one of the bores forms one of the fluid outlet openings at one of its ends or open into one of these. In this way, by means of a system of bores which can be realized in a simple manner from a manufacturing standpoint, the cooling channel system can be realized in the drum shell in a simple manner.According to a further advantageous embodiment, in order to achieve a respectively correspondingly good cooling performance, it is provided that at least one of the cooling channels-preferably naturally a plurality or all of the cooling channels-pass through the upper drum part over more than 50%, in particular more than 70%, of its vertical extension.It is advantageous in this case--since it is easy to produce--if the bores forming the cooling ducts are each aligned at an angle to one another.In this way, a wide variety of configurations of cooling channels can be realized. Thus, according to one embodiment, one or more of the bores forming the cooling channels in the upper drum part jacket can extend within the (preferably otherwise conical) upper drum part jacket as far as into a (preferably cylindrical) drum neck vertically above a separating plate stack, where the respective cooling channel in this region opens in each case into one of the cooling channel outlet openings, through which the fluid F exits from the upper drum part. This advantageously ensures that the centrifugal drum can be efficiently cooled down to the region of the drum neck.Alternatively and / or in addition to the "open" outlet openings in the drum shell, it can be provided in each case that the fluid is conducted through the cooling channels as far as into a peeling disk chamber rotating with the centrifugal drum, in which the fluid is conducted by means of a peeling disk provided only for this purpose through a fluid outlet from the rotating centrifugal drum, wherein this peeling disk chamber is preferably formed axially above any peeling disk chamber(s) for product phase discharge. As a result, a good cooling effect can again be achieved over a substantial part of the drum extension and the fluid can be discharged under pressure from the cooling ducts. This variant is also suitable for the realization of an open or a closed coolant system or cooling circuit, respectively.According to a further particularly preferred embodiment variant of the invention, it can be provided that for collecting the fluid F emerging from the centrifugal drum, a collecting channel extending around the centrifugal drum is provided, with which the emerging fluid is received during operation of the centrifuge and from which it is discharged through a suitable downstream further channel or a tube from the hood which surrounds the centrifugal drum.According to a preferred variant, it is provided that the cooling device of the separator is designed as a part of a superordinate, in particular closed, cooling fluid circuit in which the fluid is guided in the circuit again and again and is thus used again. It can then advantageously be provided that the cooling fluid circuit has a heat exchanger, with which it is ensured 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.Alternatively, the fluid can also be taken from a source such as a water inlet and disposed of after passing through the drum. In such an embodiment, it may also be advantageous to be able to control or regulate the cooling fluid flow, if appropriate, with one or the control device.According to a further advantageous embodiment, it can be provided that the cooling fluid is supplied through a rotary feedthrough into a rotating drive spindle and from there into the actuation chamber or that it is supplied by spraying water into a radially inwardly open annular channel of the centrifugal drum, which is in fluid communication with the actuation chamber.According to a further advantageous embodiment, at least one temperature sensor can then 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 regulation computer program.According to a further advantageous embodiment, it can be provided that one or more springs additionally act on the piston slide. Thus, for example, it can be provided that a closing force of the fluid in the actuating chamber can be supported by means of additional springs below the piston slide. This can ensure that the piston slide remains held in the closed position even at low rotational speed or standstill of the centrifugal drum, if the total force of the springs-which acts as 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 rotational speed.In such a configuration, the centrifugal drum can be moved down to a standstill without the solids outlet openings of the centrifugal drum opening. Before the centrifuge is started up again, it is then possible to suck off the remaining liquid phase from the stationary centrifugal drum.The invention also provides a method of operating a centrifuge according to any of the claims related to the centrifuge. This method can have the following method steps: a) Providing the centrifuge during operation and the fluid F and b) Continuing to convey the fluid cooled to a defined temperature through the actuation chamber and the one or more cooling channels in the drum shell with a defined volume flow, in particular between emptying solids.In this way, a continued cooling of the centrifugal drum, which is designed to be particularly advantageous in terms of design for this purpose, is easily achieved, in particular also in the region of the drum jacket thereof.According to an advantageous variant of this method, it can be provided that during step b) first a conveying of the fluid cooled to a defined temperature through the actuating chamber and only then a conveying of the fluid through the one or more cooling channels takes place with a defined volume flow.For controlling or regulating the cooling, it is advantageous if during method step b) temperature measurement values are repeatedly measured, in particular in the centrifugal drum or in the product run-off or at another suitable point.According to an advantageous variant, the fluid is guided in an open circuit. However, it can also be carried in a closed fluid circuit.In an advantageous embodiment of the method, it can be provided that a fluid pressure is generated with a pump and / or that a required volume flow is set with a valve, with which the fluid F flows through the cooling channels, wherein a required control signal for this is generated by the control device.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.In a further advantageous embodiment of the method, it can then be provided that the cooling fluid is supplied through a rotary feedthrough 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.It is particularly advantageous if the coolant flow is controlled or regulated by the control device in order to achieve a temperature setpoint value, for example, at the measurement point at which the temperature sensor is arranged.Further advantageous embodiments of the invention can be taken from the remaining dependent claims.The invention is described in more detail below with reference to the drawings.It shows: FIG. 1 is a view of a centrifuge according to the invention in full section with a raised piston slide and closed outlet openings; FIG. 2 : a view of the centrifuge from FIG. 1 in full section with the piston slide raised in the right-hand half of the illustration and the piston slide lowered in the left-hand half of the illustration; FIG. 3 : an enlarged detail from FIG. 1 ; FIG. 4 is a view in full section of an embodiment variant of the centrifuge from FIG. 1 ; FIG. 5 : the centrifuge from FIG. 4 with a closed fluid circuit; FIG. 6 is a view in full section of an embodiment variant of the centrifuge from FIG. 1 with the piston slide raised and the outlet openings closed; FIG. 7 : shows a schematic view in full section through a self-emptying separator according to the prior art.In the following description of the figures, various exemplary embodiments are described. Individual features of these exemplary embodiments can also be combined with exemplary embodiments not shown and are also each suitable as advantageous embodiments of the subject matter described in individual ones or more of the main claims and dependent claims.FIG. 7 shows a centrifuge designed as a self-emptying separator for the continuous processing of a product. The spinner drum has a vertical axis of rotation. In addition to a centrifugal drum 1, the separator also has further components-not shown overall here-such as a control computer, a drive motor for rotating the centrifugal drum 1, a hood 2, a solids catcher 3, etc. In the centrifugal processing of the product, it is separated into a plurality of product phases, which may comprise at least one liquid phase or a plurality of liquid phases and at least one solid phase.In the context of this document, a solid phase is also understood to mean a sludge phase, as a mixture of solids and little liquid.A drive motor (not shown) is provided for driving the rotatable spinner drum 1. This is preferably effected 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. continuous and non-batch processing of a product P in the centrifugal field.The centrifugal drum 1 here has a lower drum part 5 and a lower drum part jacket 5 aand an upper drum part 6 with an upper drum part jacket 6 a. The lower drum part jacket 5 aand the upper drum part jacket 6 atherefore jointly form a drum jacket 1 a. The upper drum part 6 and the lower drum part 5 preferably consist of metal. They can be formed, for example, as metallic forged parts.In the single- or double-conically shaped centrifugal drum 1, a stack of conical separating disks 8 of conical separating disks 9 can be arranged in the drum interior 7-which is also called a centrifugal chamber as synonym. The separating plates 9 are then generally arranged on a distributor shaft 10 of a distributor 11.An inlet pipe 12 serves for feeding in a suspension to be processed or a product P to be processed. The inlet pipe 12 is here designed as a stationary element which does not rotate during operation (however, it could alternatively also be designed to be rotatable). It extends concentrically to the axis of rotation D into the centrifugal drum 1. according to FIG. 7, it projects in a preferred, but not obligatory, embodiment from above into the centrifugal drum 1.The flowable product P to be processed--here preferably human blood--is fed through the feed pipe 12 into the centrifugal drum 1. The product P emerging from the free end of the inlet pipe 12 flows into radially extending distributor channels 13 of the distributor 11 and is entrained in the latter as a result of the rotations of the rotating centrifugal drum 1 or is accelerated in the circumferential direction. The distributor channels 13 open into the drum interior 7 with the plate stack 8.In the drum interior 7-also called a centrifugal chamber-the separation of the product P to be processed takes place in a centrifugal field into at least two distinct dense phases, of which at least one phase is a liquid phase Lp. In the example of FIG. 7, the product P is separated into a solid or sludge phase Sp into two liquid phases Lp1, Lp2of different density. Alternatively, it is also possible to clarify the product P into a solid phase Sp and into only one liquid phase Lp or in more than two liquid phases Lp.The solids Sp are ejected to the outside of the centrifugal drum 1 by circumferentially distributed, radially extending solids outlet openings 14-preferably in the region of the largest radius / circumference of the centrifugal drum 1.The solid outlet openings 14 can be designed in the manner of nozzles. They are assigned an opening and closing mechanism. As shown by way of example in FIG. 7, this has a hydraulically actuatable piston slide 15 arranged in the lower drum part 5, with which slide the solids outlet openings 14 can be opened and closed again discontinuously. For this purpose, fluid is conducted into an actuating chamber 23 below the piston slide 15. The fluid F required for this purpose, e.g. water, is conducted by means of valves (not shown here) for closing the solid outlet openings 14 under the piston slide 15 in order to move the latter under the action of the lifting forces which are produced during the rotation of the drum, and can also be discharged from there again in order to open the solid outlet openings 14. Alternatively, the supply of the fluid F can also be effected by a rotary guide in lines in the rotating drive spindle 4 and further by a passage (not shown here) into the centrifugal drum 1.The piston slide 15 is shown open in the left-hand half of the illustration in FIG. 7 and closed in the right-hand half of the illustration in FIG. 7.According to FIG. 7, two fluid drains 16 a, bare provided by way of example. The lighter first liquid phase Lp 1 running radially inward out of the disk stack 8 flows into a first peeling disk chamber 17, which rotates with the centrifugal drum 1. In the first peeling disc chamber 17 a first peeling disc 18-also referred to as gripper-is arranged. This first peeling disk 18 is arranged in the first peeling disk chamber 17 in a stationary manner, e.g. arranged non-rotatably on the inlet pipe 12. The first peeling disk 18 is provided to discharge the lighter first liquid phase Lp 1 from the centrifugal drum 1, so that the lighter first liquid phase Lp 1 leaves the centrifugal drum 1 via the first liquid outlet 16 a.The heavier second liquid phase Lp2 draining radially further outwards from the disk stack 8 flows into a second peeling disk chamber 19, which likewise rotates with the centrifugal drum 1. A second peeling disk 20 is arranged in the second peeling disk chamber 19. This second peeling disk 20 is likewise arranged in a stationary manner in the second peeling disk chamber 19. The second peeling disk 20 is provided to discharge the heavier, second liquid phase Lp2from the centrifuge drum 1, so that the heavier, second liquid phase Lp2 verlässt the centrifuge drum 1 via the second liquid outlet 16 b.Temperature sensors can be provided in the fluid flows 16 aand / or 16 b, which transmit temperature measurement values of the liquid phases to the control device.The peeling disks 18, 20 each operate according to the operating principle of a centripetal pump.It is provided that the fluid F for lifting the piston slide 15, i.e. for closing the solid outlet openings 14 for the solid or sludge phase Sp, is also used simultaneously for cooling the centrifugal drum 1 (see FIG. 1 ).For this purpose, a fluid F can be brought by suitable means to the required temperature for cooling the spinner drum 1 before it is conducted into the spinner drum 1. As in self-emptying separators known from the prior art, the fluid F is continuously sprayed, for example radially from the inside outwards, through stationary nozzles (not shown here) which do not rotate with the drum during operation into an open collecting chamber 21 of the rotating centrifugal drum 1 and from there is conducted 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 feed principle shown in FIG. 1 is also referred to as an "open feed system". This feeding principle can be implemented particularly easily in terms of design. However, it does not necessarily have to be used.This is because, according to an alternative embodiment, the fluid F can also be conducted in another manner-for example through a rotary feedthrough (not shown here) into channels within the drive spindle 4 and from there further into the closing chamber 23. This feed principle can also be referred to as a closed feed system.When the actuating chamber 23 is filled, the piston slide 15 rises and closes the solids outlet openings 14 for the solids or sludge phase Sp on the outer periphery of the centrifugal drum 1. Since a part of the fluid continues to escape from the actuating chamber 23 through the channels 24, the piston slide is pressed downward by the product P in the drum interior 7.One or more features of the prior art are also realized in the embodiments according to the invention.According to an exemplary embodiment of the invention, see FIG. 1, it is then provided that cooling channels 24 for cooling the centrifugal drum 1 distributed over the circumference of the centrifugal drum 1 extend both in the lower drum part jacket 5 aand in the upper drum part jacket 6 ato cool the centrifugal drum 1, as is illustrated by way of example in FIG. 1.In this respect, the actuating chamber 23 is in fluid communication with the cooling channels 24 in the lower drum part jacket 5 aand in the upper drum part jacket 6 a.The cooling channels 24 are preferably implemented in a simple manner in terms of design by holes in the metallic drum shell 1 a. This can be implemented in various ways. Some preferred configurations are realized below, but these can vary by the person skilled in the art. Thus, it can determine, in an experiment and / or by calculation, a particularly advantageous course of the cooling channels in the drum shell.First, as shown in FIGS. 1-6, first, here vertical, bores 24a are arranged in the lower drum part jacket 5a, for example, in a circumferentially distributed manner, in each case between the outlet openings 14, one end of these vertical bores 24a being in fluid communication with the actuating chamber 23 and the other end of these first vertical bores 24a being in fluid communication with continuing bores 24b, 24c, 24d, 24e running in the upper drum part jacket 6a, which bores together form one of the cooling channels 24.A respective second bore 24 bextends here substantially horizontally in the upper drum part jacket 6 aand is in fluid communication with the respective bore 24 ain the lower drum part jacket 5 a. The respective second, here horizontal, bore 24 bis adjoined here by a third bore 24 cextending substantially parallel to an inner geometry of the here inner and outer conical upper drum part jacket 6 a. The respective third bore 24 cis adjoined here by a fourth bore 24 d, which likewise runs substantially parallel to the inner geometry of the upper drum part jacket 6 a. The respective fourth bore 24 dis adjoined here by a vertically running fifth bore 24 e. These bores 24 b, 24 c, 24 d, 24 eforming the respective cooling channel 24 in the upper drum part jacket 6 arun within the upper drum part jacket 6 aup to a drum neck 25 above the separating plate stack 8.The respective cooling channel 24 ends there at a respective cooling channel outlet opening 26, through which the fluid F-a liquid, for example water-exits radially outwards from the upper drum part 6. During operation of the centrifuge, the emerging fluid F is here taken up by a collecting trough 27 extending around the centrifugal drum 1 and discharged from the hood 2 through a tube or a channel.In an optional embodiment of the invention, the fluid F can be conducted through the cooling channels 24 as far as into a third peeling disk chamber 28 rotating with the centrifugal drum 1, in which the fluid F can then be conducted through a fluid outlet 35 out of the rotating centrifugal drum 1 by means of a third peeling disk 29 which is stationary during operation of the centrifuge and operates according to the operating principle of a centripetal pump, as is represented purely by way of example in FIGS. 4 and 5. The third peeling disc chamber 28 and thus the third peeling disc 29 are arranged here axially above the second peeling disc chamber 19 and the second peeling disc 20. The discharge of the fluid F through the third peeling disk 29 has the advantage that the discharge of the fluid F from the drum shell 1 atherefore takes place in a closed manner and under pressure.The position and the course of the cooling channels 24 and thus the position of the bores 24 a, 24 b, 24 c, 24 d, 24 emay also be configured differently from that illustrated in FIGS. 1, 2, 6. An alternative is shown, for example, in FIGS. 4 and 5. Here, the fifth bore 24 eof the respective cooling channel 24 passes through almost the entire drum neck 25 in the axial direction, in order to finally open into the third peeler disk chamber 28 in the cooling channel outlet opening 26 directed radially inward here. It is essential that the cooling channels 24 are arranged within the drum lower part jacket 5 aand within the drum upper part jacket 6 a.In order for the piston slide 15 to be raised and the solids outlet openings 14 to remain closed, the fluid F must be supplied permanently to the actuating chamber 23 of the centrifugal drum 1 and keep it filled, while at the same time fluid F flows out of the actuating chamber 23 into the cooling ducts 24. This continuous flow of the fluid F through the cooling ducts 24 also brings about constant cooling of the centrifugal drum 1.This ensures that with one and the same fluid F both the centrifugal drum 1 is kept closed and the centrifugal drum 1 is cooled.Contamination of the solid or sludge phase Sp emptied from the centrifugal drum 1 by the fluid F likewise emerging from the centrifugal drum 1 is avoided structurally by the arrangement of the collecting trough 27 and the solid catcher 3 spaced vertically one above the other, as is illustrated 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 centrifugal drum 1 according to the exemplary embodiment of the centrifuge shown in FIG. 4 or 5.In both cases, as an alternative to the illustration according to FIGS. 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 illustrated purely by way of example in FIG. 5, wherein the required fluid pressure can be generated with a pump 30. A valve 31 can be used to set the required volume flow with which the fluid F flows through the cooling ducts 24, a required control signal for this being generated by a control device 32. Alternatively, a regulated pump can also be provided, with which the volume flow of the fluid F can be regulated. In such a case, the valve 31 can be omitted.In the fluid circuit FC, it can also be ensured with a suitable heat exchanger 33 that the temperature of the fluid F flowing into the cooling channels 24 is regulated in such a way that the product to be separated-in this case human blood-is cooled to the required temperature. This can likewise be regulated and / or monitored by the control device 32 by, for example, detecting the fluid temperature in the inlet and / or in the outlet of the heat exchanger with sensors. The temperature of the product phase Lp1 and / or Lp2 (not shown) can also be detected with suitable sensors. These temperature measurement values are passed on to the control device and evaluated in order to realize a suitable regulation which ensures compliance with the required product temperature in the drum.An additional buffer container with a fluid inlet (not shown here) can be provided in the fluid circuit FC in order to be able to compensate for any fluid losses in the fluid circuit FC. For this purpose, the buffer container can be equipped with a fill level sensor which is connected to the control device 32 which opens a valve in the fluid inlet of the buffer container when a fill level is undershot and closes this valve again when the limit value is exceeded.In a further embodiment variant of the separator according to the invention, the centrifugal drum 1 is emptied in the following manner: During a rotation of the centrifugal drum at an operating rotational speed of, for example, more than 3000 U / min, the inflow of the fluid F is interrupted, for example by the valve 31 (see FIG. 5 ), which is controlled by the control device 32 (see likewise FIG. 5 ), so that a part of the fluid F flows out of the actuation chamber 23 through the cooling channels 24 and exits into the collecting trough 27 and the actuation 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 less than the force exerted on the piston slide 15 by the product P located in the centrifugal drum 1. As a result, the piston slide 15 is pressed downward, as a result of which the solids outlet openings 14 are released, as is illustrated by way of example on the left-hand side of FIG. 2. The centrifugally separated sludge or solid phase Sp can be discharged. As soon as the fluid F is conducted again into the actuating chamber 23 of the centrifugal drum 1 and fills the latter, the piston slide 15 rises again and closes the solids outlet openings 14.In an embodiment of the separator according to FIG. 6, the closing force of the fluid F in the actuation chamber 23 can be assisted by additional springs 34, which are provided below the piston slide 15 between the latter and the drum lower part and which can press this piston slide 15 vertically upwards. This makes it possible to ensure that the piston slide 15 remains held in the closed position even at low rotational speed or standstill of the centrifugal drum 1 if the total force of the springs 34, which acts as closing force on the piston slide 15, is selected to be greater than the opening force acting on the piston slide 15 by the product P at low rotational speed of the drum.In such a configuration, the centrifugal drum 1 can be moved down to a standstill without the solids outlet openings 14 of the centrifugal drum 1 opening. Before the centrifuge is started up again, it is then possible to suck off the remaining liquid phase from the stationary centrifugal drum 1.Alternatively, after standstill, the centrifugal drum 1 can also be accelerated again without fluid F in the actuation chamber 23. The piston slide 15 is then pressed into its open position at a specific speed. This is effected by the pressure which arises when the product P remaining in the drum interior 7 is pressed against the piston slide 15 by the centrifugal force. In this way, the centrifugal drum 1 can be emptied before it is accelerated to operating speed for a further separating process. Before the centrifugal drum 1 is charged again with product P, the fluid F for actuating the piston slide 15 and for cooling the centrifugal drum 1 is conducted into the actuating chamber 23 and the cooling channels 24, 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 the processing of 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 jacket 5 aand in the drum upper part jacket 6 aand the latter therefore does not require any special cleaning.The following method is provided for the operation of a centrifuge according to the invention:In a first method step, the centrifuge during operation-in particular at an operating speed-and the fluid F brought to a defined temperature are provided.In a second method step, the fluid F cooled to a defined temperature is conveyed through the one or more cooling channels 24 at a defined volume flow, in particular between emptying solids.During the second method step, the temperature in the spinner drum 1 is measured. It is then possible to increase or decrease the delivery rate of cooling fluid in a controlling or repeatedly regulating manner in order to adapt the temperature in a controlling or regulating manner to a setpoint value.List of reference characters1 Centrifugal drum 1 a: drum shell 2: hood 3: solids catcher 4: drive spindle 5: drum lower part 5 a: drum lower part shell 6: drum upper part 6 a: drum upper part shell 7: drum interior 8: separating plate stack 9: separating plate 10: distributor shaft 11: distributor 12: inlet pipe 13: distributor channel 14: outlet opening 15: piston slide 16 a, b: liquid outlet 17: first peeling plate chamber 18: first peeling plate 19: second peeling plate chamber 20: second peeling plate 21: capture chamber 22: channel 23: actuation chamber 24: cooling channel 24 a, b, c, d, e: bore 25: drum neck 26: cooling channel outlet opening 27: capture trough 28: third peeling plate chamber 29: third peeling plate 30: pump 31: valve 32: control device 33: heat exchanger 34: spring 35: fluid outlet D: axis of rotation P: product Lp 1, Lp2 Liquid phase Sp Solid phase F Fluid FC Fluid circuitReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 24 23 319

[0004] DE 10 139 466 A1

[0005] DE 26 31 110

[0006] DE 1 922 237 C2

[0009] DE 199 22 237 C2

[0015]

Claims

Centrifuge which is designed as a self-emptying separator with a vertical axis of rotation and which is provided for separating a product P to be processed, in particular blood, in a centrifugal field into at least two phases, 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) solid outlet openings (14) which are designed in a circumferential manner in the drum shell (1a) and which serve for the outlet of solids Sp from the centrifugal drum (1), c) a piston slide (15) which can be actuated hydraulically by means of a fluid and by means of which the solid outlet openings (14) can be opened and closed again discontinuously, d) wherein the piston slide (15) is assigned an actuating chamber (23) which can be filled with a fluid F, e) a cooling device for cooling the centrifugal drum, which cooling device is realized in that the fluid F for actuating the piston slide (15) also serves simultaneously for cooling the centrifugal drum (1), characterized in that f) extends / extend, starting from the actuating chamber (23), one or more cooling ducts (24) for cooling the centrifugal drum (1) in the drum casing (1a), which ducts are in fluid connection with the actuating chamber (23) and which can additionally - in particular following a flow through the actuating chamber - be flowed through by the fluid, g) the one or at least one of the cooling ducts in the drum casing also extends as far as a region vertically above the piston slide (15).Centrifuge according to claim 1 or according to the preamble of claim 1, characterised in that the centrifugal drum (1) has a lower drum part (5) with a metallic lower drum part jacket (5a) and an upper drum part (6) with a metallic upper drum part jacket (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 upper drum part jacket (6a) and in sections through the metallic lower drum part jacket (5a).Centrifuge according to claim 1 or 2, characterized in that the fluid is a liquid, in particular water.Centrifuge according to one of the preceding claims, characterized in that at least one or more cooling channel outlet opening(s) (26) is / are provided in the drum shell (1a) of the centrifugal drum (1), through which the fluid F exits the centrifugal drum (1), in particular radially outwards.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 in that, starting from this actuating chamber (23), the one or at least one of the cooling channels (24) initially runs on or through the lower drum part jacket (5a) and then merges into the upper drum part (6) in a region between the lower drum part jacket (5a) and the upper drum part jacket (6a).Centrifuge according to one of the preceding claims, characterized in that a plurality of the cooling channels (24) are arranged in a circumferentially distributed manner in the centrifugal drum casing (1a).Centrifuge according to claim 4, characterised in that the cooling channels (24) arranged in a circumferential manner are each carried out vertically or substantially vertically between two of the solids discharge openings.Centrifuge according to one of the preceding claims, characterized in that the cooling channel or channels (24) in the centrifugal drum jacket (1a) each have one or more bores (24a, 24b, 24c, 24d, 24e) in the centrifugal drum jacket (1a).Centrifuge according to claim 7, characterised in that the bores of the cooling channels (24) run both in the lower drum part jacket (5a) and in the upper drum part jacket (6a), and in that in each case at least one of the bores forms one of the fluid outlet openings at one of its ends or opens into one of these.Centrifuge according to one of the preceding claims, characterized in that at least one or more of the cooling channels pass through the upper drum part over more than 50%, in particular more than 70%, of its vertical extent.Centrifuge according to one of the preceding claims, characterized in that the bores forming the cooling ducts (24) are each aligned at an angle to one another.Centrifuge according to one of the preceding claims, characterized in that one or more of the bores (24b, 24c, 24d, 24e) forming the cooling ducts (24) in the upper drum part jacket (6a) extend within the upper drum part jacket (6a) as far as into a drum neck (25) vertically above a separator plate stack (8), where the respective cooling duct (24) in this region respectively opens into one of the cooling duct outlet openings, through which the fluid F exits from the upper drum part (6).Centrifuge according to one of the preceding claims, characterized in that the fluid is conducted through the cooling channels (24) as far as into a peeling disc chamber rotating with the centrifugal drum, in which the fluid is conducted by means of a peeling disc provided only for this purpose through a fluid outlet from the rotating centrifugal drum, wherein this peeling disc chamber is preferably formed axially above any peeling disc chamber(s) for product phase discharge.Centrifuge according to one of the preceding claims, characterized in that a collecting channel extending around the centrifugal drum (1) is provided for collecting the fluid F emerging from the centrifugal drum.Centrifuge according to one of the preceding claims, characterized in that the cooling device of the separator is designed as part of a superordinate cooling fluid circuit which has a heat exchanger, wherein the throughflow of the fluid can be controlled and / or regulated by means of a control device.Centrifuge according to one of the preceding claims, characterized in that the fluid can be removed from a source such as a water inlet and is disposed of after passing through the drum, wherein the fluid medium supply can be controlled or regulated by means of a or the control device.Method according to one of the preceding claims, characterized in that the fluid is supplied through a rotary feedthrough 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).Centrifuge according to one of the preceding claims, characterized in that a temperature sensor is provided, which is coupled to the control device.Centrifuge according to one of the preceding claims, characterized in that one or more springs additionally act on the piston slide.A method of cooling a centrifuge according to any preceding claim during the centrifugal processing of a product, characterised bythe steps of: a) providing the centrifuge in operation and the fluid F and b) continuing to convey the fluid cooled to a defined temperature through the actuation chamber and the one or more cooling channels (24) in the bowl shell at a defined volume flow, in particular between emptying solids.Method according to claim 20, characterised in that during step b) first a conveying of the fluid cooled to a defined temperature through the actuating chamber (23) and only then a conveying of the fluid through the one or more cooling channels (24) takes place with a defined volume flow.Method according to one of the preceding method claims, characterized in that measured temperature values are recorded repeatedly during method step b).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 sequences.Method according to one of the preceding method claims, characterized in that the fluid F is guided in an open circuit.Method according to one of the preceding method claims, characterized in that the fluid F is guided in a closed fluid circuit FC.Method according to one of the preceding method claims, characterized in that a fluid pressure is generated by means of a pump (30).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 ducts (24) is set by means of a valve (31), wherein a required control signal for this is generated by the control device (32).Method according to one of the preceding method claims, characterized in that the temperature of the fluid F flowing into the cooling ducts (24) is cooled to a defined temperature value with the aid of a heat exchanger (33).Method according to one of the preceding method claims, characterized in that the cooling fluid is supplied through a rotary feedthrough 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).Method according to one of the preceding method claims, characterized in that the coolant supply or a coolant flow is controlled or regulated by the control device in order to achieve a temperature setpoint value.Method according to one of the preceding method claims, characterized in that an additional buffer container with a fluid inlet is provided in the fluid circuit FC, wherein the buffer container 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 falls below and closes the valve again when the limit value is exceeded.

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