DE102008048727A1 - Device for filtering media e.g. lacquer/cathodic dipping lacquer, comprises membrane filter element, inlet to introduce unfiltered medium into the device, outlet to discharge filtered medium from the device, and filtrate collection chamber - Google Patents

Abstract

The filter device (13) comprises a membrane filter element (11), which partially consists of an organic material and is equipped with an effective grounding path against Earth's mass, an inlet (6) for introducing the unfiltered medium into the filter device, an outlet (6b) for discharging the filtered medium from the filter device, and a filtrate collection chamber, which is designed for collecting the filtrate (6a) filtered off from the membrane filter element. The membrane filter element is disposed between the inlet and the outlet, so that it flows through the medium to be filtered. The filter device (13) comprises a membrane filter element (11), which partially consists of an organic material and is equipped with an effective grounding path against Earth's mass, an inlet (6) for introducing the unfiltered medium into the filter device, an outlet (6b) for discharging the filtered medium from the filter device, and a filtrate collection chamber, which is designed for collecting the filtrate (6a) filtered off from the membrane filter element. The membrane filter element is disposed between the inlet and the outlet, so that it flows through the medium to be filtered, and is equipped with a spacer and media flow channels, which are designed to flow through by the medium to be filtered. The grounding path comprises an electrically conducting media flow channel conductor, which is area-wisely positioned in the media flow channel. The media flow channel conductor completely or partially consists of conductible and/or dischargeable metallic, non-metallic or polymer material, comprises conductible and/or dischargeable metallic, non-metallic or polymer wires, metal fabric, metal gauze and/or coatings, and is formed as conductible and/or dischargeable metallic, non-metallic or polymer spacer. The membrane filter element is implemented as a winding module, where the media flow channel conductor is formed from a coating of the spacer consisting of conductive lacquer or conductive plastic. The grounding path comprises a conductor for electrical connection between the media flow channel conductor and earth. An independent claim is included for a method for filtering cathodic dipping lacquer with a filter device.

Description

The The present invention relates to a filter device according to the The preamble of claim 1, as well as a method for filtering in liquid media, especially paints, in particular cathodic dip paints, according to the preamble of claim 12.

in principle filter devices are to be differentiated into static and dynamic filters. With static filters, the membrane filter elements become complete flows through the medium, non-porous particles are retained on the surface of the membrane filter element. For dynamic filters, the membrane filter element becomes tangent and turbulent flowed over by the medium, with porängängige Passages of the medium through the membrane filter element in the filtrate collection chamber. in principle can dynamic membrane filter elements in plate, tube, Capillary, hollow fiber and wound modules differ. Especially for plate modules are in addition to the traditional plate-and-frame Design with a simple flow through the Membrane filter element further different constructive procedures known to achieve near-surface turbulence. For example, the turbulence over the membranes by self-rotation against each other or above fixed shear elements or over the membranes moving rotors or through ascending gas bubbles generated tangentially to the membrane filter element. Furthermore, the systems differ in the type of applied Pressure. In many cases, the medium is through the filter device with Pressure pumped, other methods are based on a negative pressure at the Filtrate side.

It is, for example, from the introduction to the description of EP 1 138 370 A2 It is known that filter devices with polymer-based or ceramic-based membrane filter elements can be used for cathodic dip coating (KTL) filtration. The paint is pumped by pressure through media flow channels formed by the membrane filter elements.

positive charged paint particles tend to be negatively or positively charged To adhere membrane surface. As a result, the membrane filter elements more or less fast u. a. with inorganic positively charged Lackinhaltsstoffen occupied, the only conditionally or no longer cleanable are.

Polymeric membrane filter elements, from, for example, polyvinylidene fluoride (PVDF) or cellulose acetate (CA), are negatively or positively charged, causing the above outlined Effect can be observed here. Ceramics have even more stronger negative charge than Polyvenylidenfluorid (PVDF) or Cellulose acetate (CA), whereby the effects outlined above Addition of positively charged paint particles in membrane filter elements On ceramics basis are to be expected even more.

To avert this undesirable effect, for example, in the already mentioned above EP 1 138 370 A2 a filter device proposed with ceramic-based membrane filter elements for the filtration of cathodic dip paints, in which the membrane filter elements are equipped with a Erdungspfad against earth mass. However, this alternative is not economically feasible for cost reasons.

So far used for KTL filtration polymer-based membrane filter elements For cost reasons, mostly spiral-wound modules are used and disk modules are used. But here are the ones outlined above To observe effects of the addition of positively charged paint particles. Also For this purpose, some measures have become known, the attachment of positively charged paint particles.

For example, the US 5391426 Membrane impregnations with polyethyleneimine to change the surface charge before. However, the impregnation is worn out within a few months and re-impregnation is possible on the membrane already used only with considerable effort. Removing electrostatically bound inorganic particles from organic filter membranes is only possible by disassembly of the membranes and mechanical cleaning. Disassembly of wound filter modules is structurally not provided and thus impossible. A dry cleaning is often eliminated due to lack of suitable cleaning agents. From the US 4849106 Furthermore, a modification of the membrane polymer for preventing the adhesion of positively charged particles has become known. For cost reasons, this route was not pursued.

The Object of the present invention is now in a filter device with an organic membrane filter element, in particular a polymer membrane filter element to propose, in which the membrane filter element has a lower affinity for Addition of positively charged particles, in particular paint particles to their economic feasibility, in particular to facilitate the cleaning of cathodic dipping paints.

According to the invention this object is achieved in that the membrane filter element equipped with an effective grounding path against earth mass.

By this measure can ensure that or charge-sensitive molecules in a liquid at the site of their temporary molecular charge disorder an immediate potential equalization in the form of a safe grounding path is provided, thereby neutralizing their character preserves and the danger of electrostatic binding a negatively or positively or neutrally charged organic membrane surface, in particular a polymer membrane, d. H. a plastic membrane, is prevented.

Further can by the invention proposed Measure ensure that the filter performance values are within the previously achieved filter performance values after commissioning, but a significantly longer long-term stability or a lower deposition rate of positively charged molecules the membrane filter element is achieved. By the invention Design of a grounding path for the at least one Membrane filter element can be a life extension or a fouling prevention of the membrane filter element can be achieved. With the proposed filter device can high Filtratmengen which are usually used for follow-up processes, such as B. rinses are used. Either High functional performances (filtrate performances) come to follow-up processes in qualitative terms, or filter devices may smaller and thus cost-effective dimensions. These aspects in combination with significantly longer service life allow previously unattainable cost reduction potential for to develop the generic filter devices.

Further yield advantageous embodiments of the proposed invention from the features of the subclaims.

A Another object of the present invention is to provide a method for the filtration of paints, in particular cathodic dip paints, to propose, which is a particularly economical filtering of paints, especially cathodic dip paints allows.

According to the invention this object is achieved by a method having the characterizing features of claim 12. Because of the paint with a filter device 13 Filtered according to one of claims 1 to 11, long service life of the filter device 13 guaranteed, resulting in corresponding cost savings.

1

filtrate manifold

1a

filtrate Sammelrohrperforation

2

filter membrane as a sandwich

3

straps

4

spacer (Spacer)

5

Antitelskopierstern

6

media input (Inlet)

6a

filtrate

6b

Media output / outlet (Concentrate)

6c

Media flow channel

7

filtrate

8th

sealing ring

9

sandwich adhesive seam

10

ladder

11

Membrane filter element as a winding module

12

filter housing

13

filter means

14

Media flow channel manager

A filter device according to the invention 13 is schematic in 1 shown. A filter device according to the invention 13 essentially comprises a filter housing 12 and at least one membrane filter element 11 , preferably with a number of media flow channels 6c , In particular, they are membrane filter elements 11 provided on a polymer basis.

In the membrane filter element 11 it is preferably a dynamically operated filter module. In the membrane filter element 11 it is preferably a filter fineness for micro, ultra and nanofiltration. It can also be provided that the membrane filter element 11 is designed as a filter pack with flat-layered filter membranes or as a spiral winding module with wound filter membranes. It may also be provided that the membrane filter element 11 is negative, positive or neutral. It can also be provided that the membrane filter element 11 with spacers 4 , so-called "spacers" is equipped.

In the membrane filter element 11 it is a membrane filter element consisting entirely or at least partly of organic materials, in particular polymers 11 , The membrane filter element 11 For example, polymers such as polyvinylidene fluoride (PVDF), cellulose acetate (CA), regenerated cellulose acetate, polysulfone (PS), polyethersulfone (PES), polyacrylonitrile (PAN), polypropylene (PP), polycarbonate (PC), or polyamide (PA) may be used in whole or in part consist.

The membrane filter element 11 is with at least one media flow channel 6c , preferably a number of media flow channels 6c , fitted. The at least one media flow channel 6c is adapted to be flowed through by the medium to be filtered. In 2 is a membrane filter element 11 as a winding module with several media flow channels 6c schematically in Section shown.

The mode of operation or the filtering method and further details of in 2 shown filter device arise as follows.

The medium to be filtered is the filter device via an inlet 6 fed, flows through the media flow channels 6c the organic membrane filter elements 11 and leaves the filter device 13 concentrated over an outlet 6b , The flow direction of the medium is indicated by the arrows labeled E (inlet) and A (outlet). In this design, a by-pass media stream is passed through one into an antiteleskopstern 5 inserted sealing ring 8th prevented. A filter membrane 2 is designed as a sandwich and closes a Filtratsammelkammer 7 one, in turn, with a filtrate collection tube 1 connected is. The filtrate 6a is from the membrane filter elements 11 separated, enters the filtrate collection chamber 7 and may accordingly from the filtrate collection tube 1 be withdrawn via a filtrate outlet. The flow direction of the filtrate is indicated by the arrow "F".

According to the invention, it is provided that the membrane filter element consisting at least partially of an organic material 11 with an at least partially in the media flow channels 6c mounted effective grounding path is equipped against earth mass. In particular, it is not intended that the membrane filter element 11 is a ceramic membrane filter element.

Furthermore, in 2 a collection pipe perforation 1a for the filtrate, straps 3 , as well as a sandwich adhesive seam 9 shown.

The grounding path essentially comprises at least one media flow channel conductor 14 at least partially in the at least one media flow channel 6c is appropriate. Preferably, in each media flow channel is a media flow channel conductor 14 intended. Furthermore, the grounding path comprises at least one conductor 10 for electrical connection between the media flow channel conductor 14 and a grounding.

The media flow channel conductor 14 may preferably comprise conductive or dissipative metallic, non-metallic or polymeric materials or be configured from the aforementioned materials. The media flow channel conductor 14 Alternatively or additionally, conductive or dissipative metallic, non-metallic or polymeric wires, metal knits, metal mesh and / or coatings may also be included. As far as the membrane filter element with spacers, so-called "spacers" is equipped, the media flow channel conductor 14 alternatively or additionally, conductive or dissipative metallic, non-metallic or polymeric (eg dissipative lacquer) spacers. It can also be provided that the spacers are coated with a conductive lacquer or a conductive plastic, in turn, the media flow channel conductor 14 form.

It can also be provided that the media flow channel conductors 14 are contacted with each other and over the ladder 10 connected to the grounding device attached to the filter apparatus.

The arrangement of media flow channel conductors 14 in media flow channels 6c , as well as the electrical connection by means of conductors 10 for grounding is shown schematically in 3 shown.

The proposed filter device 13 , as well as methods for filtering in liquid media, especially paints, in particular cathodic dip paints, is particularly suitable for filtering charge-unstable ingredients from media, especially liquid media. Other filtration options: Beverages, wastewater, process water, dairy, etc .. The proposed filter device 13 can preferably be used for dynamic filtration (tangential or cross-flow filtration) of solids containing liquids. In particular, the filter device is suitable 13 for liquids with solids contents <75%, <50%, <25%, especially for paints and varnishes, beverages, waste water, process water, etc.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - EP 1138370 A2 [0003, 0006]
• - US 5391426 [0008]
• - US 4849106 [0008]

Claims (12)

Filter device ( 13 ) for the filtration of media, in particular paints or cathodic dip paints, wherein the filter device ( 13 ) at least one membrane filter element ( 11 ), wherein the membrane filter element ( 11 ) consists at least partially of an organic material, characterized in that the at least partially made of an organic material membrane filter element ( 11 ) is equipped with an effective grounding path against earth mass. Filter device ( 13 ) according to claim 1, characterized in that the filter device ( 13 ) at least one inlet ( 6 ) for the entry of the unfiltered medium into the filter device ( 13 ), at least one outlet ( 6b ) for the discharge of the filtered medium from the filter device ( 13 ), wherein at least one membrane filter element ( 11 ) between the inlet ( 6 ) and the outlet ( 6b ) is arranged, that it can be flowed through by the medium to be filtered. Filter device ( 13 ) according to one of the preceding claims, characterized in that a filtrate collection chamber ( 7 ) is provided for collecting the of the at least one membrane filter element ( 11 ) Filtrates filtered out. Filter device ( 13 ) according to one of the preceding claims, characterized in that the membrane filter element ( 11 ) with at least one media flow channel ( 6c ), preferably a number of media flow channels ( 6c ), wherein the at least one media flow channel ( 6c ) is adapted to be flowed through by the medium to be filtered. Filter device ( 13 ) according to one of the preceding claims, characterized in that the membrane filter element ( 11 ) in whole or in part of a polymer, in particular polyvinylidene fluoride (PVDF), cellulose acetate (CA), regenerated cellulose acetate, polysulfone (PS), polyethersulfone (PES), polyacrylonitrile (PAN), polypropylene (PP), polycarbonate (PC), or polyamide ( PA). Filter device ( 13 ) according to any one of the preceding claims, characterized in that the grounding path comprises at least one electrically conductive media flow channel conductor ( 14 ) which at least partially in the at least one media flow channel ( 6c ) is attached. Filter device ( 13 ) according to one of the preceding claims, characterized in that the media flow channel conductor ( 14 ) consists wholly or partly of conductive or dissipative metallic, non-metallic or polymeric materials. Filter device ( 13 ) according to one of the preceding claims, characterized in that the media flow channel conductor ( 14 ) comprises conductive or dissipative metallic, non-metallic or polymeric wires, metal knits, metal mesh and / or coatings. Filter device ( 13 ) according to one of the preceding claims, characterized in that the membrane filter element ( 11 ) with at least one spacer ( 4 ), the media flow channel conductor ( 14 ) is designed as a conductive or dissipative metallic, non-metallic or polymeric spacer. Filter device ( 13 ) according to one of the preceding claims, characterized in that the membrane filter element ( 11 ) as a winding module and with spacers ( 4 ), the media flow channel conductor ( 14 ) made of a conductive lacquer or a conductive plastic coating of the spacer ( 4 ) is formed. Filter device ( 13 ) according to one of the preceding claims, characterized in that the grounding path comprises at least one conductor ( 10 ) for the electrical connection between the media flow channel conductor ( 14 ) and a ground. Process for the filtration of paints, in particular cathodic dip paints, with a filter device, characterized in that the paint is treated with a filter device ( 13 ) according to one of claims 1 to 11 is filtered. Other filtration options: Beverages, wastewater, process water, dairy, etc ..