DE1221390B - Procedure for cleaning magnetic filters - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. α .:

BOId

HOIf
German class: 23 c -1/06

Number: 1221390

File number: St 23369 VI a / 23 c

Filing date: February 13, 1965

Opening day: July 21, 1966

Magnetic methods are known which remove iron particles from a flow of liquid. at Machine tools are z. B. given the circulated cooling emulsions via magnetic separators to to free them of turnings or grindings. The separated iron parts are strong, ferromagnetic substances.

It is also known that iron oxides also have weak magnetic properties with a certain chemical composition. The naturally occurring magnetite and the hammer blows and mill scale that fall off during the hot deformation of iron belong to this material class of magnetic "ferrites" (FeO-Fe ₂ O ₃ ). In electrical communications engineering, these "ferrites" play their part, whose bivalent iron oxide is replaced by other bivalent metal oxides, such as B. CuO, ZnO, NiO, MnO, among others, is exchanged, as magnetic materials an increasing role. Even the trivalent iron oxide can be partially replaced by other trivalent metal oxides, such as. B. Al ₂ O ₃ , without the mixed crystals completely losing their magnetic properties.

Recent studies have shown that "ferrites" also work under the operating conditions of steam boilers arise and accumulate in the feed water-steam-condensate circuit. They arise through Crumbling of the magnetite protection layers from the heated pipes and also due to chemical precipitation the corrosion products of iron, brass and alloy steels. Due to the fine grain of this "Ferrites" can only be insufficiently removed from the cycle with the help of sieve or gravel filters.

The currently known magnetic separators are not particularly suitable for weakly magnetic substances when very fine-grained "ferrites" are to be separated from large amounts of liquid in pressure equipment. For many technical purposes, these magnetic filters have to be deposited quickly and without much ado Let the material free again through a regeneration process.

This gap is to be closed by the regeneration process developed on the basis of a new principle. Because The simplicity of the method is likely to be particularly useful for weakly magnetic substances, but also for fine-grain ferromagnetic, universally suitable. It can be transferred to small and large devices and apply at any operating pressure. It is known that weakly magnetic substances are best in diverging magnetic fields at the pole ends of many individual magnets with moderate, laminar Strö processes for cleaning magnetic filters

Applicant:

Investment and patent management company

with limited liability,

Essen, Altendorfer Str. 103

Named as inventor:

Dr.-Ing. Fritz Spillner, Duisburg

let the mung separate. The loaded magnetic bars are mostly regenerated by

ao build and manual cleaning. Brief, vigorous backwashing with water can be used in a well-known In this way, remove the adhering material without removing the magnets. It is about here about small filter units.

These are suitable for large filter units, especially when it comes to pressure equipment Methods little. Because of the heavy screw connections, frequent opening of the magnetic filter is a thing of the past. to be able to clean the magnets. The backwashing principle can be used with large apparatus units Use poorly, because of the technical complications required, very large amounts of water as a simple calculation example shows.

The magnetic filter should ^{clean 200 m 3 of} water per hour. About a hundred times the water speed is necessary for backwashing in order to loosen the material adhering to the magnetic poles again. It would therefore be pumps, fittings, water

water inflows and outflows required for 20,000 Va ³ Ih .

There are complex systems known that enforce a large amount of water to be purified to be able to have a large number of small filters connected in parallel, which are controlled according to a program be backwashed one after the other in order to be able to cope with the divided amounts of flushing water.

Is known z. B. also a magnetic filter, whose magnets are in a cylindrical apparatus in constant rotating movement to keep the deposits adhering to the magnets continuous to be able to shed and discharge. In the case of weakly magnetic and / or finely dispersed

609 590/354

The turbulence that occurs counteracts high-grade deposition of substances.

In the case of stationary magnet arrangements, on the other hand, which only relate to discontinuous regeneration be set in rapid motion on the surrounding liquid, the magnetic load can take place almost free of turbulence. Since no scrapers are required with the new regeneration process you have a free hand in the arrangement and dimensioning of the individual magnets.

The aim of the invention is thus a regeneration process which ^{manages with a flushing water quantity (m 3} / h) that is far below the throughput quantity (m ^s / h). There are therefore no limits to the size of the filter units. In order to detach the separated magnetic material again, the water is not led past the magnets at the appropriate speed, but the magnets are moved quickly in relation to the water. Rotational movements are suitable for large units, and translational movements and vibrations for small units. The material removed in this way only needs to be removed with a little rinse water.

In Fig. 1 shows one of the possible designs for this. In a body of revolution (1) are a plurality of permanent magnets (2) arranged between which the liquid to be cleaned (3) with slightly turbulent flow is directed longitudinally to the axis. It exits again at the top (4). A slight turbulence between the magnetic rods supports the separation effect, because it causes the Degree of probability is increased that a magnetic particle near the magnetic poles where the forces of attraction are strongest. In this way the filter throughput can be compared a purely laminar flow. One could use the water in a similar apparatus also lead in cross flow through the rotating body (Fig. 2).

When the magnets are loaded, the water flow is shut off and the rotating body so quickly moves so that the particles adhering to the magnets detach as a result of the turbulence. With little Rinsing water (5), the sludge is discharged from below (6).

In the case of the in FIG. 1 countercurrent regeneration and with axial loading it is appropriate to to put the magnet system in ίο very slow rotation during loading, so despite possibly uneven flow through the rotating body, all magnet groups equally loaded will.

Because coarse iron parts can only be removed from strong magnets with great effort can be used in front of the described Magnetnlter catching magnets in a known construction switch. In the figure, two magnetic pockets (7) are indicated near the inlet line.

Claims (3)

Patent claims: 1. A method for cleaning magnetic filters, characterized in that the removal of the substances deposited at moderate water speeds by a rapid Movement of the magnets with respect to the surrounding water takes place. 2. The method according to claim 1, characterized in that the detached magnetic substances are carried out by a stream of water, the amount of which, measured in m ^s / h, is smaller than that to be cleaned. 3. The method according to claims 1 and 2, characterized in that the magnets in rotating or oscillating movement. Considered publications:
German interpretative document No. 1 030 955. 1 sheet of drawings 609 590/354 7.66 © Bundesdruckerei Berlin