DE29816019U1 - Device for cleaning process fluids with foreign oil content (preferably cooling lubricant emulsions) - Google Patents

Description

Device for cleaning process fluids containing foreign oil
(preferably cooling lubricant emulsions)

The invention relates to a device for cleaning cooling lubricants with a foreign oil separator for separating foreign oils from the emulsion containing the cooling lubricants and a disinfection device for killing microorganisms in the emulsion by means of UV radiation, which are arranged in such a way that the emulsion flows through them one after the other.

Such a device is known from the German utility model G 94 07 292.2 and is used in particular for the reprocessing of cooling lubricants which are used, for example, in cutting and forming machine tools for lubricating and cooling the workpieces and tools. For use in these machines, the cooling lubricant is usually mixed with water to form an oil/water emulsion. The emulsion runs through a coolant circuit in the machine tool, where it is pumped from a storage tank of the machine tool to the tools and workpieces and then fed back into the storage tank. The foreign oils and other foreign substances which accumulate in the emulsion over time, as well as a number of microorganisms which increases with increasing use, can be removed using the known device by passing the emulsion pumped from the storage tank of the machine tool through a solids filter,

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a foreign oil separator and then a UV disinfection device. For this purpose, a gear pump is provided between the solids filter and the foreign oil separator and between the foreign oil separator and the disinfection device. After this successive treatment, the cleaned emulsion is returned to the storage tank of the machine tool.

The foreign oil separator of the known device is essentially formed by an inclined plate clarifier and a disk skimmer. Specifically lighter foreign oils can accumulate on the plates that are dipped into the liquid at an angle and combine to form larger droplets, which then rise along the plate surfaces to the emulsion surface. The disk skimmer then transports the foreign oils floating on the surface of the emulsion to a drain channel that opens into a collecting container. The disinfection device of the known device has two UV radiation tubes through which the emulsion flows axially, with a UV lamp arranged coaxially in each tube and separated from the emulsion by a quartz glass wall.

The disadvantage of this known device is that the deposit areas on the plates of the inclined plate clarifier are small in relation to its size and therefore a space-consuming inclined plate clarifier is disadvantageously necessary for efficient separation. Furthermore, the disc skimmer is relatively complex in design and requires its own drive motor, for example. The tubular disinfection device also has the disadvantage that the quartz glass walls become dirty after a relatively short time due to precipitation from the emulsion and as a result the intensity of the UV rays penetrating the emulsion decreases. For this reason, either frequent optical inspection or a correspondingly complex sensor system as well as time-consuming and costly cleaning of the quartz glass walls are necessary.

The object of the present invention is to further develop a device of the type mentioned at the outset in such a way that the efficiency of the device is increased in a simple and cost-effective manner - while at the same time keeping the dimensions small.

This object is achieved in the device of the type mentioned at the beginning in that the foreign oil separator contains at least one lamella pack made up of several spaced-apart lamellae with upwardly curved or inclined coalescence sections. In order to achieve the object, in a

The device of the type mentioned at the beginning also provides that the disinfection device contains a flat-bed disinfection chamber with a substantially flat floor and at least one UV lamp arranged above the floor. The object is also achieved in the device of the type mentioned at the beginning in that the foreign oil separator has a surface skimmer with a receiving chamber and a height-adjustable overflow edge.

The advantages of the plate pack according to the invention are in particular that several plates arranged at a distance from one another can be accommodated in a small space, which nevertheless provide a large deposit area for the foreign oil droplets. Since the deposition rate on the plates depends essentially on a smooth flow of the emulsion, this preferably flows horizontally through the plate pack and is diverted at the curved or inclined coalescence sections of the plates. The foreign oil droplets in the emulsion come into contact with these sections and deposit there - combining to form larger drops. Due to their low specific weight, the drops then migrate upwards along the plate surfaces until they reach a plate edge and rise to the next higher plate and finally to the liquid surface. The emulsion with reduced foreign oil, on the other hand, emerges on the downstream side of the plate pack and can, for example, be passed on to the disinfection device.

The lamellae preferably have openings in the area of their curved or inclined coalescence sections through which the foreign oil droplets pass and rise to the next higher lamella. These openings are advantageously located in the highest area of the lamellae. For example, in lamellae with two coalescence sections tapering upwards, the opening is advantageously located in the area of the abutting edge of these sections. Foreign oil droplets also collect in the downward coalescence sections downstream in the flow direction of the emulsion and migrate against this flow direction - to the openings.

Advantageously, the distance travelled by the foreign oil droplets to the surface of the emulsion is as short as possible so that as little foreign oil as possible is carried along by the liquid flow on the way from lamella to lamella and returns to the machine tool. To keep this risk to a minimum, the openings in the lamellae are preferably aligned vertically and flush.

Alternatively or additionally, two or more horizontally spaced lamella packs are provided, the adjacent lamella sections of which are curved or inclined upwards towards each other. The foreign oil droplets can rise to the liquid surface through the space between the two lamella packs - analogous to the openings mentioned above.

Preferably, the curved or inclined sections of two adjacent lamellae arranged one above the other overlap in a horizontal plane. This ensures that the horizontally flowing emulsion is necessarily diverted at the lamellae and that the foreign oil droplets in the emulsion can come into contact with the lamellae surfaces.

Since the oil separation on the lamellae is greatest with a flow-calmed emulsion, a diversion bridge is advantageously provided upstream of the lamella pack(s), which the emulsion must pass through on its way to the lamellae. This largely eliminates turbulence in the emulsion that occurs when it enters the device.

The advantage of the surface skimmer with the height-adjustable overflow edge lies in its simple construction; an electric drive is also not required. The overflow edge can be adjusted in height so that the foreign oils and the foreign oil-reduced emulsion can flow cleanly and separately into different compartments.

The surface skimmer according to the invention is preferably mounted so that it can pivot about a horizontal axis and can be locked in any pivot position. By pivoting the skimmer, the overflow edge is simultaneously pivoted and set to a new height. This makes it easy to precisely adjust the height of the overflow edge of the skimmer to the overflow edge of a drainage device, which leads the largely foreign oil-free emulsion out of the space with the foreign oil separator.

In order to keep the foreign oils floating on the emulsion surface away from the drainage device leading to the disinfection device, for example, a first separating web is preferably provided between the surface skimmer and the drainage device. Foreign oils can then not flow via the drainage device to the downstream disinfection device, where they would prevent the effective killing of the microorganisms.

So that the foreign oils can flow off in a defined manner via the surface skimmer on the one hand and the largely foreign oil-free emulsion can flow off in a defined manner via the drainage device on the other hand, a second separating web is preferably arranged between the first separating web and the drainage device, which preferably extends from the floor of the room with the foreign oil separator to the level of the overflow edge of the surface skimmer. The overflow edge of the drainage device, on the other hand, is preferably arranged slightly lower so that the emulsion can flow off after passing the upper edge of the second separating web.

Particularly preferably, a disposal pipe is connected to the receiving chamber of the skimmer, through which the foreign oils flow off into a transportable container, for example an easy-to-handle canister, after passing the overflow edge.

In order to be able to move the device according to the invention to different machine tools, for example, it is preferably designed to be mobile. For this purpose, several lockable roller wheels are expediently provided beneath the floor. The roller wheels are also preferably designed to be individually height-adjustable in order to - in addition to or as an alternative to pivoting the skimmer - adjust the height of the overflow edge of the skimmer to the upper edge of the second separating bar or the overflow edge of the drainage device. For example, the overflow edge of the skimmer and the upper edge of the second separating bar, which both preferably run horizontally, are set to exactly the same height at the factory on a flat, horizontal surface by pivoting the skimmer and locking it in this position. In later practical use, where flat surfaces are usually not found, a spirit level is used, for example, to adjust the height of the roller wheels and to adjust the horizontal position of the overflow edge of the skimmer and the upper edge of the second separating bar again.

The flatbed disinfection chamber offers the advantage that the emulsion to be disinfected can be irradiated without the need for easily contaminated separating surfaces between the UV lamp and the emulsion. Cleaning work is therefore hardly necessary, so that both downtime and costs and personnel expenditure are significantly reduced compared to the use of ring reactors. The possibly lower kill rate compared to axially flowing tubes can be counteracted by the emulsion passing through the device - or just the disinfection chamber - several times.

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Even if the described advantages of the individual measures according to the invention, i.e. the lamella package, the surface skimmer and the flat bed disinfection chamber, also arise individually, a combination of two or all measures is preferred. The best possible solution in terms of the task is achieved by combining all measures together.

Advantageous developments of the invention are characterized by the features of the subclaims.

In the following, an embodiment of the invention is explained in more detail with reference to the drawings. They show:

Figure 1 is a perspective view of a mobile device;

Figure 2 is a sectional front view of the device according to the

Figure 1;

Figure 3 is a partially sectioned side view of the device

according to Figure 1;

Figure 4 shows a cross section through a first embodiment of a

disc pack;

Figure 5 shows a cross section through an alternative embodiment

two horizontally adjacent lamella packs;

Figure 6 is a front view of a surface skimmer;

Figure 7 is a side view of the surface skimmer according to the

Figure 6; and

Figure 8 is a plan view of the surface skimmer according to the

Figures 6 and 7.

Figures 1 to 3 show a device 1 according to the invention for cleaning emulsions containing cooling lubricants with an approximately cuboid-shaped housing, which has a base 8, a cover 9, a front wall 10 and a rear wall 11 (left and right in Fig. 3) and two side walls 12.

The housing in turn is essentially divided into three approximately cuboid-shaped housing groups of equal width: In the bottom area of the device 1, a pump chamber 2 is provided in which a circulation pump 13 is arranged, which in this embodiment is designed as an eccentric screw pump that conveys the emulsion particularly gently. A separating chamber 3 extends upwards from the pump chamber 2 with a foreign oil separator 20 arranged approximately centrally therein. The separating chamber 3 closes off with the rear wall 11 of the device 1 (corresponding to the left side in Figure 3), while the front wall of the separating chamber 3 (corresponding to the right side in Figure 3) runs inwards. On the front of the device 1 in front of the separating chamber 3, a low-level disinfection chamber 4 is provided, which closes off with the separating chamber 3 on the ceiling side and in which a disinfection device 50 is accommodated.

In front of the separation chamber 3 and below the disinfection chamber 5, a canister storage space 5 is provided for setting up a portable canister 70 (see Fig. 1). A control panel 75 is arranged near a side wall 12 of the device 1 below the disinfection chamber 5, via which the functions and operations of the individual elements of the device 1 can be specified and controlled.

On the floor 8 of the device 1, steerable rolling wheels 60 which can be locked with a parking brake 61 are arranged in all four corner areas and which can be individually adjusted in height by means of adjusting nuts 62.

The circulation pump 13 can be connected to the storage tank of a machine tool or the like via a hose (not shown in detail) in order to convey a cooling lubricant-water emulsion from this via an inlet 6 of the device 1 through the pump chamber 2, the separation chamber 3 and the disinfection chamber 4 to an outlet 7 of the device 1, to which a hose leading back to the storage tank of the machine tool or the like can be connected.

More precisely, the circulation pump 13 conveys the emulsion to an inlet pipe 14, which runs close to a side wall 12 of the device 1 from the pump chamber 2 upwards into the separating chamber 3, is bent downwards by 180° in the ceiling area of the separating chamber 3 and opens just above the floor of the separating chamber 3. Between the inlet pipe 14 and the foreign oil separator 20, a diversion web 18 is provided, which extends over the entire depth of the separating chamber 3 and projects upwards from the floor thereof, the upper edge 19 of which is above the

Separation chamber 3 is arranged in the opening 15 of the inlet pipe 14. Downstream of the foreign oil separator 20, near the other side wall 12 of the device 1, a drain device 46 is provided, which in this embodiment is designed as a riser pipe and opens into the disinfection chamber 4. The outlet 7 is provided on the underside 7 of the disinfection chamber 4.

The foreign oil separator 20 essentially consists of several lamella packs 21 arranged next to one another, through which the emulsion flows one after the other, and a surface skimmer 31. The lamella packs 21 are each formed from identical lamellae 22 arranged at a distance from one another, which are attached to vertically extending support rods 24. The lamellae 22 of each lamella pack 21 are curved upwards in the cross section and have vertically aligned openings 23 in the middle.

Figures 4 and 5 show two alternative embodiments of one or two lamella packs 21, 121 in cross section. Figure 4 shows a lamella pack 21 whose lamellae 22 arranged one above the other have upwardly curved coalescence sections 25 on which foreign oil droplets from the emulsion can be deposited. The flow direction of the emulsion is indicated by solid arrows. In their highest region (relative to Figure 4), the coalescence sections 25 have vertically aligned openings 23 through which the foreign oil droplets - after they have migrated upwards along the surfaces of the coalescence sections due to their lighter specific weight compared to the emulsion - can pass through and rise to the liquid surface (see dashed arrows).

Figure 5 shows two horizontally spaced lamella packs 121 with flat, inclined lamellae 122. In this embodiment, the coalescence sections 125 are formed by the entire lamellae 122. In this embodiment, the foreign oil droplets migrating upwards on the surfaces of the lamellae 122 can rise through the space 123 between the two lamella packs 121.

The surface skimmer 31 of the foreign oil separator 20 is arranged at the level of the upper slats 22 (see Fig. 2 and 3). As can be seen in more detail in Figs. 6 to 8, the surface skimmer 31 is designed as a narrow channel open at the top with a receiving chamber 32, the upwardly extending side walls 36 of which extend essentially from the front to the back of the

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Separation chamber 3. The side walls 36 are connected to one another at the front via end walls 37, while a floor 38 closes off the receiving chamber 32 at the bottom. To the front of the device 1, the receiving chamber 32 is connected to a substantially horizontally running disposal pipe 34 (see Fig. 6 and 7), which opens into the canister 70, for example, via a downwardly curved pipe section (Fig. 1).

The surface skimmer 31 is pivotally mounted about a horizontal axis 35, which runs centrally through the disposal pipe 34 at a low height above the floor 38, which therefore rotates about its own longitudinal axis when the surface skimmer 31 is pivoted. The upper free edges of the side walls 36 simultaneously represent overflow edges 33, via which foreign oils can enter the receiving chamber 32.

Between the surface skimmer 31 and the drainage device 46 there is a first separating web 40 which runs essentially vertically from the ceiling of the separating chamber 3 and extends over its entire depth, the lower edge 41 of which ends at approximately the middle height of the separating chamber 3. Between the first separating web 40 and the drainage device 46 there is a second separating web 44 which runs upwards from the floor of the separating chamber 3 and also extends over its entire depth, the upper edge 45 of which ends with the lower of the two overflow edges 33 of the surface skimmer 31, depending on the pivoting position of the skimmer 31.

The embodiment of the drainage device 46 shown in Figures 2 and 3 consists of a vertically projecting pipe section with an upstream opening 48 and a downstream horizontal pipe section that opens into the disinfection chamber 4. The horizontal chamber section has an overflow edge 47, which is arranged slightly below the overflow edge 33 of the skimmer 31 and the upper edge 45 of the second separating web 44.

The disinfection device 50 has a substantially flat base 53 and at least one UV lamp 52 arranged above the base 53 (Figure 3). The opening of the outlet 7 leading out of the disinfection chamber 50 is arranged at a small height above the base 53, so that the filling level of the emulsion in the disinfection chamber 50 is always low and the UV radiation can penetrate it over the entire filling level.

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Solid arrows are shown in Figure 2 to illustrate the flow movement of the emulsion in the pump chamber 2, the separating chamber 3 and the disinfection chamber 4 when the device 1 is in operation. The emulsion is led via the inlet pipe 14 into the separating chamber 3 and from there upwards over the diversion bridge 18, resulting in a calmer flow movement in the area of the foreign oil separator 20. The emulsion then passes through the lamella packs 21, with foreign oil droplets depositing on the emulsion surface over time. As the pumping time increases, the emulsion level in the separating chamber 3 rises to the overflow edge 33 of the skimmer 31 or the upper edge 45 of the second separating web 44 (see Fig. 2), so that on the one hand the floating foreign oil flows into the receiving chamber 32 of the skimmer 31 and on the other hand the emulsion with reduced foreign oil flows after passing the lower edge 41 of the first separating web 40 over the upper edge 45 of the second separating web 44 to the drain device 46 and - if the hydrostatic pressure is sufficiently high - to the disinfection device 50 and then back to the storage tank of the machine tool. The foreign oils, on the other hand, flow from the receiving chamber 32 via the disposal pipe 34 into the canister 70, the contents of which can then be easily disposed of or processed.

The device 1 according to the invention can be moved to different machine tools and there - if necessary with the help of a spirit level - can be balanced via the adjusting nuts 62 in such a way that the lower of the two overflow edges 33 of the surface skimmer 31 and the upper edge 45 of the second separating web 44 again assume their preferably factory-set same height and horizontal alignment.

Claims (15)

1. Device for cleaning an emulsion containing cooling lubricant, with a foreign oil separator ( 20 ) for separating foreign oils from the emulsion and
a disinfection device ( 50 ) for killing microorganisms in the emulsion by means of UV radiation,
which are arranged in such a way that the emulsion flows through them one after the other,
characterized in that the foreign oil separator ( 20 ) contains at least one plate pack ( 21 ; 121 ) made up of several plates ( 22 ; 122 ) arranged one above the other at a distance from one another and having upwardly curved or inclined coalescence sections ( 25 ; 125 ). 2. Device according to claim 1, characterized in that the slats ( 22 ) each have at least one opening ( 23 ) in the region of the curved or inclined coalescence sections ( 25 ). 3. Device according to claim 2, characterized in that the openings ( 23 ) are vertically aligned and preferably aligned. 4. Device according to claim 1, characterized in that two horizontally spaced lamella packages ( 121 ) are provided, the adjacent lamella sections ( 125 ) of which are curved or inclined upwards towards one another. 5. Device according to one of the preceding claims, characterized in that the curved or inclined coalescence sections ( 25 ; 125 ) of two adjacent slats ( 22 ; 122 ) arranged one above the other overlap in a horizontal plane. 6. Device according to one of the preceding claims, characterized by a diversion web ( 18 ) which is provided upstream of the plate pack(s) ( 21 ; 121 ). 7. Device for cleaning an emulsion containing cooling lubricant, in particular according to one of the preceding claims, with
a foreign oil separator ( 20 ) for separating foreign oils from the emulsion and
a disinfection device ( 50 ) for killing microorganisms in the emulsion by means of UV radiation,
which are arranged in such a way that the emulsion flows through them one after the other,
characterized in that the foreign oil separator ( 20 ) has a surface skimmer ( 31 ) with a receiving chamber ( 32 ) and a height-adjustable overflow edge ( 33 ). 8. Device according to claim 7, characterized in that the surface skimmer ( 31 ) is pivotally mounted about a horizontal axis ( 35 ) for adjusting the height of the overflow edge ( 33 ) and can be locked in any pivot position. 9. Device according to claim 7 or 8, characterized in that a first separating web ( 40 ) is arranged between the surface skimmer ( 31 ) and a drainage device ( 46 ) which leads out of the space ( 3 ) with the foreign oil separator ( 20 ). 10. Device according to claim 9, characterized in that a downwardly closing and upwardly extending second separating web ( 44 ) is provided between the first separating web ( 40 ) and the drainage device ( 46 ) and that the overflow edge ( 33 ) of the surface skimmer ( 31 ) and the upper edge ( 45 ) of the second separating web ( 44 ) are arranged at approximately the same height or can be set to the same height. 11. Device according to claim 10, characterized in that an overflow edge ( 47 ) of the drainage device ( 46 ) is arranged slightly below the overflow edge ( 33 ) of the surface skimmer ( 31 ) and the upper edge ( 45 ) of the second separating web ( 44 ). 12. Device according to one of claims 7 to 11, characterized in that a disposal pipe ( 34 ) is connected to the receiving chamber ( 32 ), via which the foreign oils can be introduced into a transportable vessel ( 70 ), preferably a canister. 13. Device for cleaning an emulsion containing cooling lubricant, in particular according to one of the preceding claims, with
a foreign oil separator ( 20 ) for separating foreign oils from the emulsion and
a disinfection device ( 50 ) for killing microorganisms in the emulsion by means of UV radiation,
which are arranged in such a way that the emulsion flows through them one after the other,
characterized in that the disinfection device ( 50 ) contains a flat-bed disinfection chamber ( 4 ) with a substantially flat floor ( 53 ) and at least one UV lamp ( 52 ) arranged above the floor ( 53 ). 14. Device according to one of the preceding claims, characterized in that the device is mobile. 15. Device according to claim 14, characterized by a plurality of individually height-adjustable roller wheels ( 60 ) arranged below the bottom of the device.