EP2512691B1 - Method and device for electrostatically separating paint overspray using an absorbant - Google Patents

Description

The invention relates to a method for separating overspray from the overspray-laden car exhaust air of coating systems, in particular paint systems, in which the overspray is taken up by an air stream and passed to an electrostatic working separation device, where a majority of at least the solids from the overspray at least a separation surface is deposited.

1. a) wenigstens einer Abscheidefläche, an welcher die Kabinenabluft entlang führbar ist und welche mit einem Pol einer Hochspannungsquelle verbunden ist;
2. b) einer im Luftstrom angeordneten Elektrodeneinrichtung, welche der Abscheidefläche zugeordnet und mit dem anderen Pol der Hochspannungsquelle verbunden ist.

In addition, the invention is concerned with a device for separating overspray from the overspray-laden cabin exhaust air from paint shops

1. a) at least one separation surface, on which the cabin exhaust air is guided along and which is connected to a pole of a high voltage source;
2. b) a arranged in the air flow electrode means which is associated with the Abscheidefläche and connected to the other pole of the high voltage source.

1. a) einer Beschichtungskabine, in welcher die Gegenstände mit Beschichtungsmaterial beaufschlagbar sind und durch welche ein Luftstrom geleitet werden kann, der entstehende Overspraypartikel des Beschichtungsmaterials aufnimmt und abführt;
2. b) einer elektrostatisch arbeitenden Abscheidevorrichtung.

Moreover, the invention relates to a system for coating, in particular for painting objects, in particular of vehicle bodies, with

1. a) a coating booth in which the articles can be exposed to coating material and through which an air stream can be passed, which receives and removes resulting overspray particles of the coating material;
2. b) an electrostatic working separation device.

A method and a device with the features mentioned in the preamble of claims 1 and 15 is out WO 90/012 649 known.

In the case of manual or automatic application of lacquers to objects, a partial flow of the lacquer, which generally contains both solids and / or binders and solvents, is not applied to the article. This partial flow is called "overspray" in the professional world. The overspray is detected by the air flow in the paint booth and fed to a separation, so that the air can be optionally returned to the coating booth after a suitable conditioning.

Especially in systems with greater paint consumption, for example in systems for painting vehicle bodies, preferably wet separation systems are used. In the case of wet separators known from the market, water flows together with the exhaust air from the cabin to an air flow accelerating nozzle. In this nozzle there is a turbulence of the flowing cabin exhaust air with the water. During this process, the overspray particles largely pass into the water, so that the air leaves the wet scrubber substantially cleaned and the overspray paint particles are de-adhesive in the water. From this they can then be recovered or disposed of.

In known wet scrubbers relatively much energy is required to circulate the required quite large amounts of water. The treatment of the rinse water is costly due to the high use of paint-binding and detackifying chemicals and the Lackschlammentsorgung. Furthermore, the air absorbs a lot of moisture due to the intensive contact with the rinse water, which in turn results in a high energy consumption for the air treatment in the recirculation mode.

In known from the market devices of the type mentioned in contrast is deposited dry way by ionized by the passing cabin exhaust air entrained paint Overspraypartikel by the electrode device and migrate due to the built-up between the Abscheidefläche and the electrode device electric field to Abscheidefläche, at which they separate. The adhering to the separation surface paint Overspraypartikel can then, for example, mechanically stripped and transported away from this.

The cleaning effect of such separators is very high. For continuous operation, however, it must always be ensured that a sufficiently strong electric field can form between the deposition surface and the electrode device, which is possible only up to a certain layer thickness of paint overspray on the deposition surface, since such a layer has an insulating effect , However, the required continuous removal of the paint overspray from the separation surface is associated with structurally quite complex measures and can be prone to failure. It may also happen that overspray on the Abscheidefläche so reacts, hardens or dries, so that it can not be removed by simply stripping the Abscheidefläche.

Object of the present invention is therefore to provide a method, a separation device and a system of the type mentioned, which take into account these problems.

This object is achieved in the method of the type mentioned in that an electrically conductive material or mixture of materials is used as a release agent, which is applied to the at least one separation surface of the separator and at the working temperature of the separator has a waxy consistency.

According to the invention, therefore, a waxy material is used as a separating layer between the separation surface and the overspray so that it can not come into contact with the separation surface. The predetermined property of the release agent, the release agent can be easily stripped or peeled off the Abscheidefläche, with it adhering overspray is removed from the Abscheidefläche and its disposal or optionally a treatment can be supplied.

The consistency of the release agent is chosen so that it adheres to the separation surface over its desired period of use, but does not adhere to it. In the present case, a material is understood to be waxy if its viscosity at the working temperature is above about 2000 mPa s. The viscosity of the release agent is preferably above 2500 mPas, more preferably above 3000 mPas and more preferably above 4000 mPas.

The release agent preferably has a consistency comparable to that of hard paraffin at the working temperature. For example, block chocolate also has a similar consistency. This means that the release agent is largely solid at the working temperature, whereby rasps can be peeled off by the release agent.

Alternatively, the release agent at the working temperature has a plastic consistency. A suitable consistency is, for example, with those of fat, paraffins, such as Vaseline, of soaps, waxes and gels. Preferably, such a release agent is kneadable or spreadable at the working temperature.

The working temperature is usually below about 28 ° C.

If the viscosity of the release agent decreases at a temperature above the working temperature, this can be exploited to apply the release agent in a warmer state in liquid form on the Abscheidefläche, where it is more viscous at the working temperature and remains largely dimensionally stable. If the release agent is sprayable in a warmer state, the application of the release agent can be done accordingly by spraying.

It is favorable if the release agent is substantially inert to the separated solids. In this way, an unwanted reaction of the release agent with the overspray is excluded from the outset.

It has proved to be useful if the release agent comprises a fat, a paraffin, a soap, a wax or a gel.

If it is desired to dispense with a continuous stripping of the overspray, when using the waxy material as release agent on the at least one separation surface existing release agent with deposited solids removed after a period of time and unloaded release agent are applied to the at least one separation surface. The cleaning of the separation surface can thus take place at intervals.

It is advantageous when removing release agent with separated solids by means of a scraper, for which purpose the at least one separation surface and the scraper are moved relative to each other. In this case, the separation surface is preferably moved relative to an immovable stripping element. However, the relative movement can also be reversed.

If the at least one stripping element comprises at least one outlet opening, in particular an outlet slot, from which a fluid, in particular compressed air, can escape, a direct contact of the stripping element with the separation surface can be dispensed with. As a result, an increasing contamination of the stripping element is at least slowed down over time.

The application of unladen release agent is particularly advantageous by the at least one separation surface is moved into a dip tank filled with release agent and again out of this. Here, the release agent is preferably present at a temperature at which its viscosity is reduced from that at the working temperature.

Alternatively, the release agent can be sprayed or sprayed onto the at least one separation surface.

The working period may be about 2 hours, about 4 hours, about 6 hours, about 8 hours, about 10 hours, or about 12 hours. With lower loading of the release agent with overspray and a longer working period of up to several days is possible, as long as the insulation effect of overspray does not affect the formation of field lines so that proper operation of the separator is no longer possible. Here, the corona is an indicator of the loading of the separation area with Overspray. Due to the insulating effect of adhering to the release agent overspray, the corona current decreases with increasing thickness of the overspray layer. The corona current is usually determined empirically and is usually a few milliamperes per high voltage electrode.

• c) ein elektrisch leitfähiges Material oder Materialgemisch als Trennmittel auf die wenigstens eine Abscheidefläche aufgebracht ist, welches bei der Arbeitstemperatur der Vorrichtung eine wachsartige Konsistenz aufweist.

In a device of the type mentioned above, the above object is achieved in that

• c) an electrically conductive material or material mixture is applied as a release agent on the at least one Abscheidefläche, which has a waxy consistency at the working temperature of the device.

With regard to the release agent, the above said to the procedure.

The device advantageously comprises a release agent renewal device, by means of which on the at least one Abscheidefläche existing release agent with deposited solids removable and / or unloaded release agent can be applied to the at least one Abscheidefläche.

It is advantageous if the release agent renewal device comprises at least one scraper element which is movable relative to the at least one deposition surface. This means that either the stripping element can be moved relative to the immobile separation surface or the separation surface relative to the immovable stripping element.

It is advantageous if the at least one stripping element is coupled to a push chain drive.

The wiping effect is advantageously increased if holding means are provided, by which the at least one stripping element can at least temporarily be held in contact with the at least one Abscheidefläche.

It has proved to be advantageous if the holding means comprise a magnet), in particular an electromagnet.

In particular, it is advantageous if the release agent renewal device comprises a dip tank filled with release agent and a conveying device by means of which the at least one separation surface is movable into and out of the dip tank.

Alternatively, the release agent renewal device may comprise a nozzle device, by means of which the release agent can be sprayed or sprayed onto the at least one separation surface.

It is favorable if the at least one separating surface is the outer surface of a plate-shaped separating element. Such a separation element is easy to handle and offers large separation surfaces in relation to its volume.

An effective deposition can be achieved if the electrode device has a corona section and a field section, wherein the corona section is arranged upstream of the field section in the flow direction of the overspray-laden cabin air.

• c) die elektrostatische Abscheidevorrichtung nach einem der Ansprüche 15 bis 32 ausgebildet ist.

In the above-mentioned system, the above-mentioned object is achieved in that

• c) the electrostatic precipitating device according to one of claims 15 to 32 is formed.

The plant according to the invention thus comprises a separation device with one or more of the features mentioned above for the device. The advantages that can be achieved correspond to the advantages explained above for the method and the device.

Figur 1

eine Lackierkabine einer Oberflächenbehandlungsanlage mit einem ersten Ausführungsbeispiel einer Overspray-Abscheidevorrichtung in einer Vorderansicht;

Figur 2

eine perspektivische Ansicht von vier Abscheideeinheiten sowie von vier Elektrodeneinrichtungen der Abscheidevorrichtung von Figur 1;

Figuren

3A bis 3D Schnitte durch eine Trennmittel-Erneuerungseinrichtung in verschiedenen Arbeitsphasen entlang der Schnittlinie III-III in Figur 1;

Figur 4

als zweites Ausführungsbeispiel eine der Figur 1 entsprechende Ansicht einer Lackierkabine mit einer abgewandelten Overspray-Abscheidevorrichtung;

Figur 5

als drittes Ausführungsbeispiel eine den Figuren 1 und 4 entsprechende Ansicht einer Lackierkabine mit einer nochmals abgewandelten Overspray-Abscheidevorrichtung;

Figuren 6A bis 6D und Figuren 7A bis 7C

Schnitte durch eine abgewandelte Trennmittel-Erneuerungseinrichtung in verschiedenen Arbeitsphasen, wobei die Schnitte denjenigen der Figuren 3A bis 3D entsprechen;

Figur 8

eine perspektivische Ansicht eines Abschnitts eines als Druckluftdüse ausgebildeten Abstreifelements einer Abstreifeinrichtung in größerem Maßstab;

Figur 9

einen Schnitt einer Abstreifeinrichtung entlang der Schnittlinie IX-IX in Figur 10;

Figur 10

eine Seitenansicht der Abstreifeinrichtung von Figur 9;

Figur 11

eine Draufsicht auf die Abstreifeinrichtung der Figuren 9 und 10.

Embodiments of the invention are explained below with reference to the drawings. In these show:

FIG. 1

a painting booth of a surface treatment plant with a first embodiment of an overspray separation device in a front view;

FIG. 2

a perspective view of four deposition units and four electrode devices of the separator of FIG. 1 ;

characters

FIGS. 3A to 3D show sections through a release agent renewal device at different stages of work along the section line III-III in FIG FIG. 1 ;

FIG. 4

as a second embodiment, one of FIG. 1 corresponding view of a spray booth with a modified overspray separation device;

FIG. 5

as a third embodiment, a the FIGS. 1 and 4 corresponding view of a spray booth with a further modified overspray separation device;

FIGS. 6A to 6D and FIGS. 7A to 7C

Cuts through a modified release agent renewal device in different stages of work, the cuts those of FIGS. 3A to 3D correspond;

FIG. 8

a perspective view of a portion of a trained as a compressed air nozzle stripping a stripping device on a larger scale;

FIG. 9

a section of a scraper along the section line IX-IX in FIG. 10 ;

FIG. 10

a side view of the stripping device of Figure 9;

FIG. 11

a plan view of the stripping device of Figures 9 and 10th

First, on the FIGS. 1 to 3 Referenced. There is a total of 2 a spray booth a surface treatment system referred to, in which vehicle bodies 4 are painted after they were in the paint booth 2 upstream, not specifically shown pretreatment stations, for example, cleaned and degreased. The painting booth 2 rests on a steel structure 6, as it is known in and of itself.

The spray booth 2 comprises an overhead painting tunnel 8, which is bounded by vertical side walls 10 and a horizontal cabin ceiling 12, but open at the ends and downwards in such a way that over-laden cabin exhaust air can flow down. The cabin ceiling 12 is formed in the usual way as the lower boundary of an air supply space (not shown) with filter cover.

At the level of flanked by the lower edges of the side walls 10 lower opening 14 of the painting tunnel 8, a steel structure 16 is arranged, which in and of itself known Conveyor system 18 carries, which will not be discussed here. With this vehicle body 4 to be painted can be transported from the input side of the painting tunnel 8 to its output side. Inside the paint tunnel 8 are not specifically shown application devices, by means of which the vehicle bodies 4 can be applied in a manner known per se with paint. The lower opening 14 of the painting tunnel 8 is covered by a walk-in grate not specifically shown.

Below the paint booth 2 there is a plant area 20, in which the overspray particles carried by the cabin air are separated from the cabin air. The plant area 20 is bounded by a housing not specifically provided with a reference numeral, which in FIG. 1 only indicated as a dashed line.

The plant area 20 comprises a flow area 22, which is open towards the top of the spray booth 2 and is defined by two air baffles 24 and 26. This in FIG. 1 The left-hand air baffle 24 comprises a section 24a, which, viewed from the outside inwards, initially slopes moderately downwards and which merges into a section 24b with a steep gradient. In a corresponding manner, this includes in FIG. 1 right air baffle 26 a relatively little downwardly inclined portion 26 a and a steep portion 26 b.

The air baffles 24 and 26 open at the bottom in a deflection region 28, in which a lower baffle 30 and the air baffle 26 continuing arcuate section 32 ensure that the flowing from top to bottom cabin air in a direction from bottom to top by a in FIG. 1 right next to the first flow region 22 arranged separating space 34 flows.

Distributing channels 36a, 36b attached laterally next to the air guide plates 24 and 26 allow a separating liquid to flow down onto the air guide plates 24 and 26 and in a substantially continuous layer at their outer surface facing the painting booth 2. The separating liquid absorbs a part of the over-air carried by the cabin air, while the cabin air flows from the painting booth 2 downwards to the deflection region 28.

The deposition liquid laden with overspray flows via the lower guide plate 30 into a collecting container 38 arranged on the side of the air guide plate 24 remote from the separating chamber 34. From there, the separating liquid can be supplied to a cleaning and treatment process in which it is known in and of itself is freed from the paint overspray. Then, the separation liquid can be supplied to the distribution channels 36 again in a cycle.

In the separation chamber 34, a separation unit 40 of an electrostatic separation device 42 is arranged. After the cabin air has flowed through the separation unit 40, it is guided from above the separation unit 40 to an air conditioner, not shown, with which the cleaned air is brought back to the correct temperature and humidity, so that they again the air supply space above the spray booth. 2 where it is optionally mixed with fresh fresh air. On the side remote from the collecting container 38, a third distributor channel 36c is provided in the lower guide plate 30, from which separator liquid flows via the part of the lower guide plate 30 extending below the separator unit 40.

The separating unit 40 comprises a multiplicity of rectangular separating plates 44 arranged one behind the other in the longitudinal direction of the separating space 34, four of which are in FIG FIG. 2 are shown. The respective opposite outer surfaces of the Abscheideplatte 44 form Abscheideflächen 46 and 48, of which in FIG. 2 only those shown on the left most deposition plate 44 are provided with reference numerals.

At its upper edge, the separation plate 44 supports on each side a plurality of rollers 50, of which only in FIG. 2 one can be seen on each side and also bear only the rollers of the figure leftmost in the separator plate 44 reference numerals. The separation unit 40 comprises for each separation plate 44 each a guide rail 52, which are formed as a cross-sectionally C-shaped profiles. The guide rails 52 are horizontal and arranged such that the opening of the "C" faces downward. The separation plates 44 run by means of their rollers 50 in each case a guide rail 52 and can in FIG. 1 to the right out of the separation chamber 34 into a release agent renewal area 54 (cf. FIG. 1 ) are driven. In their operating position, the separation plates 44 are arranged in their associated guide rail 52 in the separation chamber 34 and locked in this.

In the separation unit 40, the guide rails 52 are arranged parallel to each other in such a way that between each two adjacent Abscheideplatten 44 remains a distance sufficient that two adjacent Abscheideplatten 44 can each receive an electrode device 56 between them. Of these, only the one in FIG. 2 rightmost electrode device provided with reference numerals.

Each electrode device 56 is connected to one pole of it associated high voltage source 58, of which in FIG. 1 only a single is indicated schematically. The deposition plates 44 are connected to ground potential via the other pole of the high voltage source.

Alternatively, all electrode devices 56 may be powered by a single common high voltage source.

Each electrode device 56 comprises two straight, mutually parallel electrode strips 60a, 60b. These hold in a field section 62 of the electrode device 56, a grid electrode 64, whose edges extending between the electrode strips 60a, 60b perpendicular to these. In a corona section 66 of the electrode device 56, the electrode strips 60a, 60b hold a plurality of corona wires 68 acting as a spraying electrode. The corona wires 68 extend perpendicular to them in a plane predetermined by the electrode strips 60a, 60b and are arranged at equal distances from one another.

The number of corona wires 68 of the electrode device 56 and their distance from one another may vary depending on the deposition behavior of the overspray particles. In the present embodiment, four corona wires 68 per electrode means 56 are provided.

As in the FIGS. 1 and 2 can be seen, the electrode means 56 have an overall extension which corresponds approximately to the extension of the separation plates 44 of the separation unit 40.

Each separation plate 44 is provided on both separation surfaces 46 and 48 each with a layer 70 of an electrically conductive wax-like material or mixture of materials, which acts as a release agent and prevents deposited overspray at the Abscheideflächen 46, 48 of the deposition plates 44 attached. The layers 70 are each between 0.2 mm and 2 mm thick. In practice, a thickness of the layers 70 of 1 mm has proven to be useful.

In the present case, a wax-like material is understood as meaning a material which has a plastic consistency at the working temperature of the separating device 38. Preferably, the release agent is kneadable or spreadable at the working temperature. The waxy material should thus be relatively supple, but to a large extent dimensionally stable at the working temperature of the separating device 38 and, if at all, show only a very limited flow behavior. The working temperature of the separator 38 is usually below 28 ° C, but may also be higher depending on the application.

In the present case, a material is selected whose viscosity, moreover, decreases to temperatures above the working temperature and is lower at a temperature above the working temperature than at the working temperature.

In practice, for example, fats, in particular paraffins, soaps, waxes and gels have proved to be useful release agents. As paraffin good results could be achieved with Vaseline. Waxes can be either of natural origin or synthetically produced and defined according to some mechanical-physical properties. In the present case, wax is understood in particular to mean a material which can be kneaded at the working temperature of the separating device 40, melts at high temperatures without decomposition, is slightly less viscous, ie slightly liquid, slightly above the melting point.

The conductivity of the release agent is basically such that charge can flow off, and is preferably in the range of 50 to 5000 μS / cm, in particular from 1000 to 3000 μS / cm. The conductivity of the release agent may optionally be adjusted via additives such as salts.

In addition to the separation unit 40, the separation device 42 has a release agent renewal device 72, which is arranged in the release agent renewal area 54 (see FIG FIG. 1 ).

The release agent renewal device 72 comprises a carriage 74 which is movable on a pair of rails 76, which runs in the longitudinal direction of the painting booth 2, so that the carriage 74 can be moved along the entire separation unit 40. The carriage 74 is driven by means of a motor / control unit 78. The motor / control unit 78 also serves to operate a guided by the carriage 74 telescopic device 80, by means of which a horizontally extending rail profile 82 can be raised or lowered in the vertical direction. This is in FIG. 1 illustrated by a corresponding double arrow. The rail profile 82 corresponds in cross section to the guide rails 52 of the separation unit 40. The telescopic device 80 is arranged on the side remote from the separation unit 40 side of the carriage 74.

In the rail profile 82, a clamping shoe 84 is movably guided, which in FIG. 1 indicated by a double arrow. The clamping shoe 84 is also controlled by the motor / control unit 78. The carriage 74 also carries a heatable by a heater 86 dip tank 88, which is filled with release agent 90. The release agent 90 in the dip tank 88 is heated to a temperature wherein it has a viscosity that allows coating of the separation plates 44 by immersing them in the release agent 90. The dip tank 88 carries on its horizontally and perpendicular to the direction of movement of the carriage 74 extending edges along stripping Abstreifelemente 92 a Abstreifeinrichtung 94, which in FIG. 3 can be seen in section. The stripping elements 92 are pivotably mounted on the respective edge of the dip tank 88 and can be moved toward and away from one another with their upper stripping edges 96 between a stripping position and a release position. In its stripping position remains between the scraping edges 96 a distance which corresponds to the thickness of the deposition plates 44.

Below the pair of rails 76, a revolving endless conveyor belt 98 is arranged, which also extends in the longitudinal direction of the painting booth 2 and leads to a collection area not specifically shown.

• Beim Lackieren der Fahrzeugkarosserien 4 im Lackiertunnel 8 wird die dort befindliche Kabinenluft mit Lack-Overspray-partikeln beladen. Diese können noch flüssig und/oder klebrig, aber auch schon mehr oder weniger fest sein. Die mit Lack-Overspray beladene Kabinenabluft strömt durch die untere Öffnung 14 des Lackiertunnels 8 in den ersten Strömungsbereich 22 des unteren Anlagenbereichs 20. Dort wird diese Luft durch die Luftleitbleche 24, 26 zum Umlenkbereich 28 geleitet, wobei bereits ein Teil des Oversprays von der an den Luftleitblechen 24, 26 herabfließenden Abscheideflüssigkeit aufgenommen wird. Die Kabinenluft wird durch den Umlenkbereich 28 in Richtung auf die Abscheideeinheit 40 der Abscheidevorrichtung umgelenkt und strömt dort zwischen benachbarten Abscheideplatten 44 hindurch.

The painting booth 2 explained above now works as follows:

• When painting the vehicle bodies 4 in the painting tunnel 8, the cabin air located there is loaded with paint overspray particles. These can still be liquid and / or sticky, but already more or less firm. The laden with paint overspray cabin exhaust air flows through the lower opening 14 of the paint tunnel 8 in the first flow region 22 of the lower plant area 20. There, this air is passed through the baffles 24, 26 to the deflection region 28, wherein already a part of the overspray of the the air guide plates 24, 26 downflowing separating liquid is received. The cabin air is deflected by the deflection region 28 in the direction of the separation unit 40 of the separation device and flows there between adjacent Separating plates 44 therethrough.

At the corona wires 68 of the electrode devices 56, corona discharges occur in a manner known per se, by means of which the overspray particles in the passing exhaust air of the cabin are effectively ionized.

The ionized overspray particles pass the deposition plates 44 at ground potential and the intervening grid electrodes 64 in the field portion 62 of the electrode assemblies 56. Due to the electric field formed between the grid electrode 64 and deposition plates 44, the ionized overspray particles deposit on the release agent layer 70 on the deposition plates 44 remain largely attached to the release agent layer 70.

Optionally dripping from the separation plates 44 down overspray is received by the flowing over the lower baffle 30 Abscheideflüssigkeit and guided to the sump 38.

The majority of the ionized overspray particles are already deposited in the corona section 66 of the electrode device 56 on the separation plates 44. However, the electric field existing between the corona wires 68 and the respective deposition plate 44 of the deposition unit 40 is inhomogeneous than the electric field in the region of the grid electrode 64, for which reason there is a more directed deposition of the ionized overspray particles on the corresponding deposition plate 44. As a result, the overspray particles which have passed through the corona section 66 are also effectively deposited in the field section 62.

The cleaned when passing through the separation unit 40 Air is, as mentioned above, fed back to the paint tunnel 8 after a certain conditioning.

For a proper operation of the separation unit 40, it must be ensured that a sufficiently strong electric field can form between the separation plates 44 and the electrode devices 56, which is only possible up to a certain layer thickness of deposited paint overspray on the separation surface, since a such layer has an insulating effect. The strength of the insulation effect of the constructed overspray layer can be determined by the power requirement of the separation unit 40, which generates the corresponding corona current, which decreases over time.

In addition, solid particles and also binder components from the deposited overspray migrate from the surface of the release agent layers 70 into the release agent. After a certain period of operation there is a risk that solid particles migrate to the separation surfaces 46, 48 and settle there, which severely impair the functioning of the separation unit 40 and would require extensive cleaning and maintenance.

If the insulating effect of the deposited overspray is therefore too great and / or proper operation of the separation unit can no longer be guaranteed, the release agent layers 70 are now removed from the separation plates 44 with overspray adhering thereto and the separation surfaces 46, 48 of the deposition plates 44 are replaced with new, provided unused release agent.

For this purpose, the rail profile 82 is brought to the telescopic device 80 of the release agent renewal device 72 in a position in which it with the guide rail 52 of to be cleaned separating plate 44 is aligned. For this purpose, on the one hand the carriage 74 is moved on the pair of rails 76 in a corresponding position and on the other hand, the telescopic device 80 extended accordingly.

The clamping shoe 84 is moved in the rail profile 82 towards the front in the direction of the separation plate 44, where he grips the same. The above-mentioned locking the Abscheideplatte 44 in the guide rail 52 is released. The clamping shoe is now moved back in the direction of the telescopic device 80, where it now pulls the separation plate 44 with it. The distance between the rail profile 82 and the corresponding guide rail 52 is so small that the separation plate 44 can easily drive on their rollers 50 from the guide rail 52 out in the rail section 82 into it.

The separation plate 44 is moved in the rail profile 82 in a position in which it is above the dip tank 88 with the stripping 94. This position of the separation plate 44 is in FIG. 1 shown with dotted lines.

The stripping elements 92 of the stripping device 94 are brought into their stripping position and the separation plate 44 is immersed by means of the telescopic device 80 in the heated release agent 90 in the dip tank 88. This is in FIG. 3A shown.

As can be seen there, the separation plate 44 travels past the stripping elements 92 on its way down. As a result, the release agent layers 70 adhering to the deposition plate 44 are stripped off the deposition plate 44 with the overspray 100 deposited thereon and fall down onto the conveyor belt 98, which projects into the FIGS. 3A to 3D not shown.

As mentioned above, the release agent dropped from the separation plate 44 with the overspray is conveyed by the conveyor belt 98 to a collection area. From there it is fed to a treatment. For this purpose, the material mixture can be heated, for example, whereby the release agent is liquid. The mixed liquor release and overspray material mixture thus obtained may hereinafter be described e.g. be separated by suitable filters.

Alternatively, the release agent / overspray mixture may also be centrifuged, optionally under pressure, and the resulting phases separated therefrom. The thus purified release agent can then be kept flowable by appropriate heat and recycled in a cycle to the dip tank 88. The filtered overspray, in turn, may optionally be sent for further treatment or its disposal, as it is known per se.

In their lowest position, the in FIG. 1 is shown with dashed lines, the separation plate 44 is now freed from the used release agent layer 70 and adhering overspray 100 and immersed in the release agent 90 in the dip tank 88th

Now the stripping elements 92 are brought into their release position (see FIGS. 3B and 3C ).

By means of the telescopic device 80, the separation plate 44 is now raised again and moved out of the release agent 90 out (see Figure 3D ). Release agent adhering to the separation plate 44 cools rapidly in the cooler environment in relation to the immersion bath, so that it exits the release agent bath when discharged has its use viscosity and adheres as a new release agent layer 70 to the separation plate 44 when it has been moved completely out of the dipping bath 88.

Then the now provided with a new and unloaded release layer 70 separating plate 44 is retracted again in its associated guide rail 52 of the separation unit 40 by the telescopic device 80 is extended accordingly and the clamping shoe 84 is moved in the direction of the separation unit 40. When the separation plate 44 assumes its operating position of its guide rail 52, it is locked there, whereupon the clamping shoe 84, the separation plate 44 releases. The process can then be repeated with another deposition plate 44, which must be freed from the release agent with adhering overspray.

In a modification, the release agent renewal device comprises a plurality of dip tanks 88 and a plurality of telescopic devices 80 with rail profile 82, so that a plurality of separation plates 44 can be treated simultaneously.

FIG. 4 shows a second embodiment, a paint booth 1002, which is associated with a separation device 1042. Components corresponding to those of FIGS. 1 to 3 correspond, bear the same reference numerals plus 1000.

In contrast to the painting booth 2, no deflection area is provided in the lower area 1020. Instead, the flow area 1022 defined by the air baffles 1024 and 1026 is adjoined by the separation chamber 1034, in which the separation unit 1040 is arranged. The lower cabin opening 1014 extends here between the upper ends of the air baffles 1024 and 1026, which then diverge down to the separation chamber 1034 out.

The lower cabin opening 1014 is flanked by deposition sheets 1102 which are moderately downwardly sloping outwardly and formed outwardly into a collection trough 1102a. The separation plates 1102 may be supplied with a separation liquid from distribution channels 1036, which are arranged next to the air guide plates 1024 and 1026.

The cabin air flows in this embodiment from top to bottom through the separation unit 1040, so that the electrode means 1056 are respectively arranged such that the corona portion 1066 above and the field portion 1062 is below.

The separation plates 1044 are not guided in horizontal guide rails, but releasably suspended in holding units 1104, which are arranged just below the lower ends of the air baffles 1024 and 1026. The holding units 1104 are controllable in such a way that they either hold or release the separating plates 1044.

In contrast to the release agent renewal device 72 after the FIGS. 1 and 3 The release agent renewal device 1072 does not include a telescopic device. For lowering and raising the separation plates 1044, rotatable driven pairs of clamping rollers 1106 are provided, which clamp the separation plates 1044 in the edge region in a conveying position on the opposite separation surfaces 1046, 1048 and can lower or raise by rotation in the corresponding direction. A guide of the separation plates 1044 in the lateral direction is ensured by lateral guide rails 1101.

Alternatively, the deposition plates 1044 in the edge region, for example, additionally grooved or with recesses be provided and instead of the pairs of pinch rollers 1106 in the corrugation or recesses engaging pinion can be used so that the promotion of the deposition plate 1044 is similar to the transport of a film from equip. In this case, a guide of the deposition plate 1044 can be ensured in the lateral direction without the vertical guide rails 1101.

So that the pairs of clamping rollers 1106 do not interfere with the movement of the carriage 1074 in the longitudinal direction of the painting booth 1002, they can also be moved laterally in the horizontal direction next to the deposition unit 1040.

Thus, when a separation plate 1044 is to be cleaned, the pinch roller pairs 1106 are moved to their conveying position and the separation plate 1044 is released from the holding units 1104 and driven downwards into the plunge pool 1088 by a corresponding rotation of the pinch roller pairs 1106. In this case, the stripping elements 1092 assume their stripping position.

Otherwise, the cleaning and the separation plates 1044 and their new coating with release agent analogous to the above to the FIGS. 1 to 3 explained procedure.

FIG. 5 shows as a third embodiment, a paint booth 2002, which is associated with a separation device 2042. Components corresponding to those of FIGS. 1 to 3 correspond to the same reference numbers plus 2000.

The basic structure corresponds to that of the paint booth 2 according to FIG. 1 , In contrast, however, the release agent renewal area 2054 is disposed above the deposition unit 2040. For this purpose, a horizontal rail 2108 is in each case on the right and left above the separation unit 2040 provided on which a modified release agent renewal device 2110 rests in the longitudinal direction of the paint booth 2002 movable.

The release agent renewal device 2110 includes a downwardly facing stripping device 2094 with stripping elements 2092, of which in FIG. 5 only one thing is recognizable. Theirs in FIG. 5 Unrecognizable scraping edges point downwards. Above this, a nozzle arrangement 2112 is arranged, which comprises a plurality of nozzles 2114 shown as a dashed circle, which are arranged on both sides of a passage slot, through which a separation plate 2044 can be guided. In FIG. 5 only one of the nozzles is provided with a reference numeral.

For raising and lowering a separating plate 2044, two clamping roller pairs 2106a arranged below the stripping device 2094 and two clamping roller pairs 2106b arranged above the nozzle arrangement 2112 are provided, so that a separating plate can be transferred from the lower clamping roller pairs 2106a to the upper clamping roller pairs 2106b and vice versa. Holding units 2104 are arranged here below the lower pairs of clamping rollers 2106a.

In order to lift a separating plate 2044 to be cleaned, the separating agent renewal device 2110 is first moved to a position above the separating plate 2044 in question. Then, the separation plate 2044 is gripped by the lower pinch roller pairs 2106a and conveyed upward after the holding units 2104 have released the separation plate 2044. The stripping elements 2092 take their stripping position, so that release agent with overspray adhering thereto is stripped off the separation plate 2044 and falls down onto the conveyor belt 2098.

After the release plate 2044 has been released from release agent, it is again moved down, now the nozzle assembly 2112 is activated. The nozzles 2114 are fed from a heatable release agent reservoir 2116 and spray or inject release agents onto both separation surfaces 2046, 2048 of the separation plate 2044. Optionally, the nozzles 2114 may also be heated to maintain the release agent at a temperature at which it can be sprayed or sprayed is.

In a modification not specifically shown here, a roller arrangement or a doctor blade arrangement is provided instead of the nozzle arrangement 2112, by means of which release agent can be rolled or knife-coated onto the separation plate 2004.

In a corresponding roller arrangement, e.g. On each side of the deposition plate 2044, a rotary roller may be arranged, each immersed in a separating agent bath. Between these rotating rollers, the separating plate 2044 is pushed therethrough, wherein the rotating rollers are arranged so that the Abscheideflächen 2046 and 2048 are uniformly wetted with release agent.

In a corresponding doctor blade arrangement, the release agent is applied in a preferably pasty form by means of a doctor blade to the Abscheideflächen 2046 and 2048.

The working periods over which a fresh release agent-coated separating plate 44, 1044, 2044 can be used and removed according to which existing release agent with deposited solids and unladen release agent is applied to the separation plate 44, 1044, 2044 depend inter alia on the behavior of the overspray from. In practice, working hours of 2 hours, 4 hours, 6 hours, 8 hours, 10 hours and 12 hours or even of several days proved to be possible.

In the FIGS. 6A to 6D and FIGS. 7A to 7C show, as a modification of the release agent renewal device 72, a release agent renewal device 3118. There, components corresponding to the components of the release agent renewal device 72 carry the same reference numerals plus 3000, and the separation surfaces 3046 and 3048 of the illustrated deposition plate 3044 are shown in FIG FIG. 6A are provided with reference numerals.

In the release agent renewal device 3118, the plunge pool 3088 and the stripping device 3094, viewed in the longitudinal direction of the paint booth 2, are arranged one behind the other on the carriage 3074. For this purpose, the carriage 3074 correspondingly larger dimensions than the carriage 74 of the release agent renewal device 72nd

The stripping device 3094 comprises a separating and overspray collecting region 3120, which is arranged below the stripping elements 3092 and is delimited by four side walls 3124 forming an upwardly and downwardly open protective box 3122.

The carriage 3072 also has a passage 3126, which is complementary to the inner cross section of the protective box 3122.

The telescopic device 3080 rests on a positioning slide 3128, which can be moved on the carriage 3074 parallel to its direction of movement. The positioning carriage 3128 is in the FIGS. 6 and 7 only indicated schematically and by dashed lines.

In the release agent renewal device 3118, the separation plate 3044 in the rail profile 3082 is moved to a position where it is above the protection box 3122 with the stripping device 3094. For this purpose, the positioning carriage 3128 is moved to a corresponding position on the carriage 3074.

The stripping elements 3092 of the stripping device 3094 are initially in their release position. The separation plate 3044 is driven downwards into the protection box 3122 by means of the telescopic device 3080 between the stripper elements 3092, without the stripper elements 3092 coming into contact with the release agent layers 3070 or the overspray 3100 adhering thereto. This is in FIG. 6A shown.

When the separation plate 3044 has its lowest, in FIG. 6B assumes the position to be recognized, the stripping 3092 be brought into its stripping position.

Then, the separation plate 3044 is moved upwards again by means of the telescopic device 3080 and, on its way upwards, moves past the stripping elements 3092, which now bear against the separation plate 3044 with their stripping edges 3096. As a result, the release agent layers 3070 adhering to the deposition plate 3044 are stripped off the separation plate 3044 with the overspray 3100 deposited thereon and fall downwardly through the protection box 3122 and the passageway 3126 in the carriage 3074 onto the conveyor belt 98, 1098, 2098 which slides into the FIGS. 6A to 6D not shown. This is illustrated by pieces of material 3130 (see Figures 6C and 6D ).

Now, the separation plate 3044 freed of the used release agent layer 3070 and overspray 3100 adhering thereto is again in its highest position above the stripping device 3094.

Then, the positioning carriage 3128 is moved to such a position that the separation plate 3044 is located above the dip tank 3088 (see FIG Figures 6D and 7A ). The separation plate 3044 is first immersed by means of the telescopic device 3080 in the dip tank 3088 with the release agent 3090 (see FIG. 7B ) and then moved out of this again (see FIG. 7C ).

As already explained above, separating agent adhering to the deposition plate 3044 rapidly cools in the environment cooler than the immersion bath, so that it has its use viscosity at the exit from the release agent bath and adheres to the deposition plate 3044 as a new release agent layer 3070, if this completely from the immersion bath 3088 was moved out.

FIG. 8 shows as a modification of a stripping element 4092, which alternative to the in the FIGS. 1 and 3 to 7 shown stripping devices 94, 1094, 2094 and 3094 can be used.

The stripping element 4092 comprises an air outlet slot 4132 running along its stripping edge 4096. The latter is connected to a compressed air connection 4134, via which the stripping element 4092 can be supplied with compressed air from a compressed air source 4136, which is then discharged via the air outlet slot 4132. This is indicated by the arrows in FIG. 8 illustrated. The compressed air may optionally be heated to a temperature such that the release agent becomes more fluid when in contact with this heated compressed air.

When such stripping 4092 for stripping with If overspray-laden release agent layers are used, their scraping edges 4096 no longer have to come into mechanical contact with the respective deposition plate 44, 1044, 2044 or 3044. Rather, a distance may remain between the respective wiping edge 4096 with the air outlet slot 4132 and the separation plate 44, 1044, 2044 or 3044. The release agent layers loaded with overspray are, as it were, blown off by the generated air flow from the separation plate 44, 1044, 2044 or 3044. Due to the remaining clearance, contamination of the stripping members 4092 against the stripping members 92, 1092, 2092, or 3092, which directly contact the release agent and the overspray, may be reduced.

Another way to remove the overspray-loaded release liners from the deposition plates 44, 1044, 2044, or 3044 is to heat-release the release agent to such a liquid state as to mix it with the overspray from the respective deposition plate 44 , 1044, 2044 or 3044. This can be done for example by heating elements or irradiation with IR radiation instead of or in addition to the stripping elements 92, 1092, 2092, 3092 or 4092. An inductive heating of the deposition plates 44, 1044, 2044 or 3044 is conceivable.

In the FIGS. 9 to 11 is designated 5094 another embodiment of a stripping device. While in the strippers 94, 1094, 2094, and 3094 described above, the separation plates 44, 1044, 2044, and 3044, respectively, are moved relative to the stationary stripping elements 92, 1092, 2092, and 3092, respectively, the stripping elements 5092a, 5092b become the scraping device 5094 moved from top to bottom relative to the separating plate 5044 to be cleaned.

The scraper 5094 will be described below with reference to the release agent renewal device 72 according to FIGS FIGS. 1 to 3 explained. However, it can be similarly used in release agent replenishers 1072, 2110 or 3118 in place of strippers 1094, 2094 and 3094. Of the release agent renewal device 72 is in the Figures 9 and 10 For the sake of clarity, only the rail profile 82 is shown.

The stripping device 5094 comprises a support frame 5138, which is carried along with the carriage 74 and is arranged stationarily above the highest position of the rail profile 82.

The support frame 5138 is symmetrical to a vertical plane, which in the assembled state of the support frame 5138 extends through the longitudinal axis of the rail profile 82. The support frame 5138 comprises two outer transverse struts 5140 extending perpendicular to this plane. Between the transverse struts 5140 extend two outer longitudinal struts 5142a, 5142b and two inner connecting struts 5144. This is particularly in FIG. 11 clearly visible.

The longitudinal struts 5142a, 5142b each carry a lifting / lowering device 5146a, 5146b for one of the two stripping elements 5092a, 5092b. Each lifting / lowering device 5146a, 5146b comprises a motor 5148a, 5148b which drives a rotational shaft 5150a, 5150b running parallel to the longitudinal bars 5142. The rotary shafts 5150a, 5150b open at each end into a respective drive block 5152a, 5152b, through each of which a push chain 5154a, 5154b runs. The lifting / lowering device 5146a thus comprises two push chains 5154a and the lifting / lowering device 5146b thus comprises two push chains 5154b. In this way, the lift / lower devices 5146a, 5148b form push chain drives for the stripping elements 5092a, 5092b.

The drive blocks 5152a, 5152b transmit the rotational movement of the rotary shafts 5150a, 5150b in a known manner to the push chains 5154a, 5154b, so that these are driven depending on the rotational direction of the rotary shafts 5150a, 5150b. The push chains 5154a, 5154b are designed in a known manner such that they can transmit a force in both the pulling direction and in the pushing direction.

Each of the two push chains 5154a is connected at one end to the support frame 5138 and at the other end to the stripping element 5092a. Similarly, each of the two push chains 5154b is connected at one end to the support frame 5138 and at the other end to the stripping element 5092b.

The drive blocks 5152a of the lift / lower device 5146a are arranged closer to each other on the longitudinal spar 5142a than the drive blocks 5152b on the longitudinal spar 5142b, so that the push chains 5154a and 5154b are offset relative to each other in the direction of the transverse spars 5140, which is particularly evident FIG. 11 easy to recognize.

The push chains 5154a, 5154b run vertically from the drive blocks 5152a, 5152b above the support frame 5138 via a deflection roller 5156a, 5156b to the respective associated stripping element 5092a or 5092b.

The stripping elements 5092a and 5092b are constructed identically and will now be described using the example of FIG FIG. 9 On the right, a wiper element 5092b is shown, wherein a reference between the wiper elements 5092a and 5092b arranged deposition plate 5044 is used.

The scraper element 5092b comprises a in use horizontally extending scraper plate 5158, which is so long that it projects beyond the separation plate 5044 on both sides. The stripper plate 5158 includes a mounting portion 5160 that slopes toward the separator plate 5044 and merges into a less inclined edge portion 5162 that eventually terminates in the stripper edge 5096.

About the mounting portion 5160 the Abstreifblech 5158 is screwed by means of a terminal block 5164 on a support bar 5166. The retaining strip 5166 is in turn at its edge remote from the deposition plate 5044 on two juxtaposed vertical support plates 5168 (see also FIG. 10 ), so that a space remains between this and the separation plate 5044 (see FIG. 9 ).

On its side remote from the stripping plate 5158, the retaining strip 5164 carries a wiper strip 5170, whereby the stripping action of the stripping element 5092b is increased.

On their sides facing the deposition plate 5044, the support plates 5168 carry a plurality of longitudinally arranged electromagnets 5172 which can cooperate with corresponding electromagnets of the stripping element 5092a arranged on the opposite side of the deposition plate 5044.

At their upper edge regions, the support plates 5168 are connected to a coupling web 5174, via which the push chains 5154b are coupled to the stripping element 5092b.

At the coupling web four roller 5176 are rotatable in such a way stored that the stripping 5092 can run on the Abscheideplatte 5044.

Instead of the stripping plates 5158, a stripping component 5092 may also be present which uses an air flow, as is the case with the stripping element 4092 according to FIGS FIG. 8 the case is.

• Zunächst sind die Elektromagnete 5172 der Abstreifelemente 5092a und 5092b deaktiviert. Die von Trennmittel und auf diesem abgeschiedenem Overspray zu befreiende Abscheideplatte 5044 wird mittels des Klemmschuhs 84 in das Schienenprofil 82 gezogen, so dass die Abscheideplatte 5044 zwischen den Abstreifelementen 5092a, 5092 zu liegen kommt (siehe Figur 9). Gegebenfalls kann vorgesehen sein, die Abstreifelemente 5092a, 5092b in einem Abstand voneinander zu halten, so dass keine Gefahr besteht, dass die Abscheideplatte 5044 beim Einfahren in das Schienenprofil 82 gegen eines der Abstreifelemente 5092a oder 5092b stößt. Hierzu können die Abstreifelemente 5092a, 5092b beispielsweise zumindest im Bereich nach des Schienenprofils 82 in seitlichen Führungsschienen laufen, welche die beiden Abstreifelemente 5092a, 5092b voneinander weg führen.

The scraper 5094 works as follows:

• First, the electromagnets 5172 of the stripping elements 5092a and 5092b are deactivated. The separating plate 5044 to be freed of release agent and overspray deposited thereon is pulled by means of the clamping shoe 84 into the rail profile 82, so that the separation plate 5044 comes to rest between the stripping elements 5092a, 5092 (see FIG. 9). Optionally, it may be provided to keep the stripping elements 5092a, 5092b at a distance from each other, so that there is no danger that the separation plate 5044 abuts against one of the stripping elements 5092a or 5092b when entering the rail profile 82. For this purpose, the stripping elements 5092a, 5092b can run, for example, at least in the area downstream of the rail profile 82 in lateral guide rails, which guide the two stripping elements 5092a, 5092b away from one another.

When the deposition plate 5044 has reached its desired position in the rail profile 82, the electromagnets 5172 are activated. As a result, the stripping elements 5092a, 5092b are pulled against the separation plate 5044.

After that, the electric motors 5148 of the lifting / lowering devices 5146 are activated such that the stripping elements 5092a, 5092b are pushed downwards along the separation plate 5044 by the push chains 5154a, 5154b. The Stripper plates 5158 of the stripping elements 5092a, 5092b are always held in contact with the separation plate 5044 by the magnetic force and the stripping elements 5092a, 5092b roll on their rollers 5176 via the separation surfaces 5046 and 5048 of the separation plate 5044.

On the way down the stripper elements 5092a, 5092b, the release agent with the overspray deposited on it is scraped off both separation surfaces 5046 and 5048 of the deposition plate 5044.

When the stripping members 5092a, 5092b have reached their lowermost position, the electric motors 5148 are operated in the opposite direction, so that the stripping members 5092a, 5092b are pulled up again by the push chains 5154a and 5154b, respectively.

Here, if necessary, separating agent residues adhering to the separating plate 5044 can be detected and removed by the wiping strip 5170.

The renewal of the release agent layer on the Abscheideplatte 5044 otherwise takes place as it above to the FIGS. 1 to 8 was explained.

Claims (33)

1. A method for separating overspray from the overspray-laden booth exhaust air of coating systems, particularly paint systems, in which the overspray is taken up by an air stream and conveyed to an electrostatically operating separating device (42; 1042; 2042) where the bulk at least of the solids is separated from the overspray on at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048)
   characterised in that
   an electrically conductive material or material mix is used as the separating agent, which is applied to the at lest one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) of the separating device (42; 1042; 2042) and has a wax-like consistency at the operating temperature of the separating device (42; 1042; 2042).
2. A method according to Claim 1, characterised in that the separating agent has a viscosity of greater than 2000 mPa s at the operating temperature, preferably greater than 2500 mPa s, more preferably greater than 3000 mPa s and particularly preferably greater than 4000 mPa s.
3. A method according to Claim 1 or 2, characterised in that the separating agent has a consistency similar to that of hard paraffin at the operating temperature.
4. A method according to Claim 1 or 2, characterised in that the separating agent has a plastic consistency at the operating temperature.
5. A method according to Claim 4, characterised in that the separating agent is kneadable or spreadable at the operating temperature.
6. A method according to one of Claims 1 to 5, characterised in that the operating temperature is below approximately 28 °C.
7. A method according to one of Claims 1 to 6, characterised in that the viscosity of the separating agent reduces at a temperature above the operating temperature.
8. A method according to one of Claims 1 to 7, characterised in that the separating agent is substantially inert with respect to the separated solids.
9. A method according to one of Claims 1 to 8, characterised in that the separating agent comprises a grease, a paraffin, a soap, a wax or a gel.
10. A method according to one of Claims 1 to 9, characterised in that separating agent with separated solids which is present on the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) is removed after an operating period and unladen separating agent is applied to the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048).
11. A method according to Claim 10, characterised in that the removal of separating agent with separated solids takes place by means of a stripping element (92; 1092; 2092; 3092; 4092; 5092), for which the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) and the stripping element (92; 1092; 2092; 3092; 4092; 5092) are moved relative to one another.
12. A method according to Claim 10 or 11, characterised in that the application of unladen separating agent takes place in that the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) is moved into a dip bath (88; 1088; 2088; 3088) filled with separating agent and out of this again.
13. A method according to Claim 10 or 11, characterised in that the application of unladen separating agent takes place in that the separating agent is sprayed or squirted onto the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048).
14. A method according to one of Claims 10 to 13, characterised in that the operating period is approximately 2 hours, approximately 4 hours, approximately 6 hours, approximately 8 hours, approximately 10 hours, approximately 12 hours or several days.
15. A device for separating overspray from the overspray-laden booth exhaust air of paint systems having

    a) at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) along which the booth exhaust air can be conveyed and which is connected to a terminal of a high voltage source (58; 1058; 2058);

    b) an electrode device (56; 1056 2056) which is arranged in the air stream, is associated with the separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) and is connected to the other terminal of the high voltage source (58; 1058; 2058);
    characterised in that

    c) an electrically conductive material or material mix is applied as a separating agent to the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) and has a wax-like consistency at the operating temperature of the device (42; 1042; 2042).
16. A device according to Claim 15, characterised in that the separating agent has a viscosity of greater than 2000 mPa s at the operating temperature, preferably greater than 2500 mPa s, more preferably greater than 3000 mPa s and particularly preferably greater than 4000 mPa s.
17. A device according to Claim 15 or 16, characterised in that the separating agent has a consistency similar to that of hard paraffin at the operating temperature.
18. A device according to Claim 15 or 16, characterised in that the separating agent has a plastic consistency at the operating temperature.
19. A device according to Claim 18, characterised in that the separating agent is kneadable or spreadable at the operating temperature.
20. A device according to one of Claims 15 to 19, characterised in that the viscosity of the separating agent reduces at a temperature above the operating temperature.
21. A device according to one of Claims 15 to 20, characterised in that the separating agent is substantially inert with respect to the separated solids.
22. A device according to one of Claims 15 to 21, characterised in that the separating agent comprises a grease, a paraffin, a soap, a wax or a gel.
23. A device according to one of Claims 15 to 22, characterised in that it comprises a separating-agent renewal device (72; 1072; 2110; 3118) by means of which separating agent with separated solids which is present on the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3036, 3048; 5046, 5048) can be removed and/or unladen separating agent can be applied to the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048).
24. A device according to Claim 23, characterised in that the separating-agent renewal device (72; 1072; 2110; 3118) comprises at least one stripping element (92; 1092; 2092; 3092; 4092; 5092) which can be moved relative to the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048).
25. A device according to Claim 24, characterised in that the at least one stripping element (5092) is coupled to a linear chain drive (5146).
26. A device according to Claim 24 or 25, characterised in that holding means (5172) are provided, by means of which the at least one stripping element (5092) can be held at least temporarily in contact with the at least one separating surface (5046, 5048).
27. A device according to Claim 26, characterised in that the holding means (5172) comprise a magnet (5172), particularly an electromagnet (5172).
28. A device according to one of Claims 24 to 27, characterised in that the at least one stripping element (4092) comprises at least one exit opening (4132), particularly an exit slot, from which a fluid, particularly compressed air, can exit.
29. A device according to one of Claims 23 to 28, characterised in that the separating-agent renewal device (72; 1072; 3118) comprises a dip bath (88; 1088; 3088) filled with separating agent (90; 1090; 3090) and a conveyor device (80, 82, 84; 1106; 3080, 3082, 3084) by means of which the at least one separating surface (46, 48; 1046, 1048; 3046, 3048) can be moved into the dip bath (88; 1088; 3088) and back out of this.
30. A device according to one of Claims 23 to 29, characterised in that the separating-agent renewal device (2110) comprises a nozzle device (2112) by means of which the separating agent can be sprayed or squirted onto the at least one separating surface (2046, 2048).
31. A device according to one of Claims 15 to 30, characterised in that the at least one separating surface (46, 48; 1046, 1048; 2046, 2048; 3046, 3048; 5046, 5048) is the outer face of a plate-shaped separating element (44; 1044; 2044; 3044; 5044).
32. A device according to one of Claims 15 to 31, characterised in that the electrode device (56; 1056; 2056) has a corona portion (66; 1066; 2066) and a field portion (62; 1062; 2062), wherein the corona portion (66; 1066; 2066) is arranged upstream of the field portion (62; 1062; 2062) in the flow direction of the overspray-laden booth air.
33. A system for coating, particularly painting, objects, particularly vehicle bodies, having

    a) a coating booth (2; 1002; 2202) in which the objects (4; 1004; 2004) are acted upon by coating material and through which an air stream can be conducted, which takes up and removes the resultant overspray particles of the coating material;

    b) an electrostatically operating separating device (42; 1042; 2042),
    characterised in that

    c) the electrostatic separating device (42; 1042; 2042) is constructed according to one of Claims 15 to 32.

Images