DE3042583C2 - Suspension filter thickener - Google Patents

Description

60

The invention relates to a suspension filter indicator for the separation, thickening and separation of Foreign matter from a suspension of low electrical conductivity, in a container with the help of a electric field between the container and filter surfaces arranged in its interior, the suspension flows through openings into the container and the filtrate behind the porous filter surface coverings is removed.

Filters for coolants and lubricants are supposed to contain foreign matter separate from the pulp to such an extent that the filtrates are reused at the points where they are needed can be. In the case of lubricating, cutting and cooling oils, the foreign matter is predominantly of a metallic nature and if they are over-enriched, they render the liquids unusable for the purposes of use.

It is an electrostatic suspension filter known (DE-OS 27 20 658), the filter surface predominantly is arranged horizontally and carries a transportable solid bed of low dielectric constant, which the foreign matter to be removed electrokinetically in itself under the influence of an electric field collects The solid bed has a limited storage capacity for foreign matter and must periodically to be renewed. Large throughputs require large filter areas and therefore in this case one large area for setting up this filter.

To fulfill these cleaning tasks, pressure or suction filters are also opened or closed Construction method used ("Ullmann's Encyclopedia of Technical Chemistry", 4th edition, Volume II, Verlag Chemie, Weinheim, pages 174-198), their filter media made of fabrics, papers, felts, laminates and / or Precoat agents exist. They work through their meshes or porea and surfaces in such a way that the Catch and / or store foreign matter. Therefore, these filter media have to be regenerated at certain time intervals or be renewed.

The foreign substances are often not removed satisfactorily in these processes or their separation is especially with high throughput rates, costly due to large filter aid consumption, regeneration effort, Loss of liquid and filtrate as well as waste disposal. The reduction of the mesh or pores in the filter aids to increase the quality of the filtrate, especially when higher viscosity fluids the hydraulic resistance and thus the resulting energy costs.

The invention is based on the object of continuously removing foreign matter from suspensions of low electrical energy Separate conductivity without the consumption of filter aid, regeneration and loss of filtrate in such a way that to thicken and deposit that, with minimal expenditure of energy, the filtrate can be reused Filter surfaces, which have only a negligible hydraulic resistance, electrically isolate yourself and stay clean.

This object is achieved by the characterizing features of claim 1.

Small portions of the suspensions thickened in the container can continuously bypass the container or intermittently removed and treated if necessary, so that afterwards the Bypass liquid can be fed back to the container.

The advantages achievable with the invention are in particular that suspended foreign substances from Liquids of low electrical conductivity can be separated continuously without any loss of filtrate and the filtrate can be reused, the foreign matter thicken and sediment, if necessary only one a small portion of the thickened sludge has to be post-treated in the bypass, none on the filter surfaces On the contrary, the consumption of filter aids occurs when the dirt particles are repelled from these filter surfaces

Pollution remain free, electrically self-isolating, do not require regeneration, negligible have hydraulic resistance, thus the energy requirement and the disposal costs are low stay. s

An embodiment of the invention is shown in the drawing and will be described in more detail below described. It shows

1 shows a suspension filter thickener in elevation,

FIG. 2 shows a cross section along section line AA in FIG. 1.

Like F i g. 1 shows, the suspension 1 flows through a ' Inlet pipe 2 into the container with electrically conductive container wall parts 3 and intermediate wall 24, which are shown at 4 are connected negatively. The suspension is mirror 5 is kept constant by a regulated flow of liquid. In the container there is a group 25 pocket-shaped filter elements 6 at equal intervals parallel to one another, immersed vertically in the suspension and connected by insulators 7 to the insulating crossbars 8 which carry the filter elements 6. the Filter elements 6 are all connected in an electrically positive manner at 9. They consist of closed bag frames 10, perforated pocket walls 11, soft an electrically conductive filter surface covering 12, for Example consisting of metal wire mesh of suitable mesh size, wear. Only those to the container walls showing pocket walls 13 are closed. The suspension 1 flows from the thickening chamber 18 into the Pocket spaces 19, is cleaned there and as filtrate 15, to the pocket interiors 20. The Closed pocket frames 10 have pipe connections 14 at the top through which the filtrate 15 passes Insulating tubes 16 is passed into the filtrate collection tube 17.

The foreign substances 21 are drawn off at the sediment drain 22 and, if necessary, in a bypass Removed partial amount of turbidity, which is removed from the thickening chamber 18 through the extraction nozzle 23 and flows through the return port 26 again.

Two sheets of drawings

Claims (2)

Patent claims: 1. suspension filter thickener for separation, Thickening and separation of foreign matter from a suspension of low electrical conductivity arranged in a container with the aid of an electric field between the container and in its interior Filter surfaces, the suspension flowing into the container through openings and the filtrate is removed from behind the porous filter surface coverings, characterized in that that the suspension (1) pocket spaces (19) between electrically conductive container wall parts (3) and / or partition walls (24) with the passage openings and the filter surface covering (12) flows through, in the container space closed, pocket-shaped filter elements (6) parallel, in the same way Spaced apart and at the same height, vertically in the constant Immerse the suspension mirror (5), the filter elements (6) The filter elements are electrically conductive and only porous to the extent that they point towards one another (6) itself, among each other and to the container wall parts (3) and / or the partition walls (24) Have optimized dimensions and spacing, electrically insulated fastened (7, 8) and insulating Pipe connections (16) for the continuous discharge of the filtrate (15) from the pocket interior (20) and by applying the same electrical potential (9) to all filter elements (6) between the filter elements (6) and the electrically oppositely connected (4) conductive container wall parts (3) or partition walls (24) exist of the same type of electrical fields, whereby the foreign matter particles (21) are transported out of the pocket interspaces (19) trektrokinetically and are pressed off by the filter surface coverings (12), thereby giving way to themselves electrically isolate, the liquid of low electrical conductivity laminar the gaps between the pockets (19) and the filter surface coverings (12), which have a negligible hydraulic resistance have, cleaned, flows through the foreign matter (2t) outside the filter elements (6) in the thickening chamber (18) of the container, in the suspension (1), thicken, deposit and through the sediment drain (22) be discharged. 2. suspension filter thickener according to claim 1, characterized in that several groups (25) of filter elements (6) and the partition walls (24) between the filter element groups (25) are angeoc ¹ -net, which is down in front of the thickening chamber (18) of the The container ends so that it remains undivided and the foreign substances (21) separated by the filter element groups (25) flow into the thickening chamber (18) unhindered.