DE7534789U - EXPRESSION FILTER - Google Patents

Description

The invention relates to a new type of squeeze filter with an Umctülpmembran.

Filters are known whose tubular filter element is concentrically surrounded by a tubular outer jacket which is closed at both ends by plates. One plate contains openings for the inflow of the suspension and discharge of the filtrate. Between the space for receiving the suspension or the filter cake and the A hose-like flexible membrane is attached to the outer jacket and is attached to both ends of the outer jacket.

Through an opening in the outer jacket, by action an excess pressure through the flexible membrane of the filter cake are additionally squeezed out. After the Filtration and squeezing is the one closure

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Plate released and the tubular filter part attached to it with your filter cake from the outer jacket pulled out. The flexible membrane remains inside the outer jacket.

This embodiment described, for example, in DOS 1 923 409 has a number of disadvantages. So seals are necessary at a total of three points, namely at the two closure plates and between a closure plate and the filter part, this results in considerable amounts Sealing problems. A connection inevitably occurs when the filter element is opened and removed between the filtrate and solids space, which can lead to solids being washed away or to a renewed impregnation of the solid ^ with filtrate, whereby the success of the filtration and pressing is diminished.

Another disadvantage is that the flexible membrane remains inside the outer jacket after the Device. As a result, solids adhering to the membrane can only be removed with difficulty and the device can only be cleaned with great difficulty which is particularly annoying when there are frequent product changes.

The object was therefore to find a device that avoids the disadvantages mentioned, but at the same time in terms of construction and manufacturing poses no greater demands than the known solutions.

The object could be achieved in an elegant and surprisingly simple way according to the invention in that the flexible membrane on one side with the internal filter element and on the other side with is connected to the open end of the outer jacket.

The filter according to the invention has a number of advantages over the known filters. This is the case with the invention filter only a single seal required.

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There is also no back-mixing when the filter is opened come from solids and filtrate. Especially with regard to cleaning the filter, e.g. for a Product change, the construction according to the invention is very advantageous because when opening the jacket and moving it out of the filter element, the flexible membrane is pulled out and turned inside out and so are all parts that come with the product come into contact, are freely accessible and can be easily cleaned. Even the seal lies Completely free when the filter is open and any solids that may have settled can be freed, which improves the sealing effect and the service life of the seal can also be favorably influenced.

In the drawings, a preferred Ausfülirungs form of the new filter is shown. Figure I is a longitudinal section through the closed filter, Figure II is a longitudinal section through the opened filter.

The tubular filter element which surrounds the filtrate space 2 is denoted by 1. 3 is the solids space that is limited by the flexible membrane 4. 5 is the one-sided closed outer jacket with the suction and pressure ports 6 urüdem flange 7. 8 is a seal between flange 7 and closure plate 9. 10 is the inlet connection for the suspension and 11 the outlet for the filtrate.

The filter element (1) is on the one hand with the closure plate (9) and on the other hand with the flexible membrane (4) firmly connected. The membrane in turn is attached to the flange (7) of the outer jacket (5) so that all components of the filter are interconnected. Therefore, if the filter element (1) is pulled out of the outer jacket (5), so at the same time the flexible membrane is pulled outwards, which turns inside out, so that the side that was previously inside (i.e. facing the solids chamber (3)), now forms the freely accessible outside.

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The opened filter (Figure II) can be easily accessed Applying negative pressure to the nozzle (6) can be closed and then vice versa by applying positive pressure again be opened. In this way, an additional drive can be saved for larger filters. the The position of the connector (6) is of minor importance and can be at any point on the outer jacket (5) be.

As soon as the filter element (1) has moved into the outer casing (5), the closure plate (9) can be opened by means of a suitable device, e.g. locking clips or screw caps, firmly against the seal (8) and the Flange (7) are pressed so that the solids space (3) is tightly closed. The suspension is then filtered through the inlet nozzle (10) into the solids space (3) pumped and the filtrate drawn off via the outlet connection (11). Is the solid roughness partially or entirely filled, the filter cake can then after closing the suspension inflow by applying an overpressure to the Nozzle (6) are also pressed out.

By applying negative pressure to the connection (6), the flexible membrane (4) detaches from the filter cake. Simultaneously the negative pressure created in the solids space (3) can be used for either a further batch the suspension to be filtered or a washing liquid to be sucked into the solids space (3). Ba even the first batch of suspension can be sucked into the solids chamber (3) with the aid of negative pressure, can in principle use pumps to fill the solids space

(3) be dispensed with with suspension or washing liquid. By alternately applying negative and positive pressure the process of filling with suspension or washing liquid and pressing can be repeated as often as

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be picked up. The uber bsw. Negative pressure can be both be generated with the help of a gas as well as a liquid.

After loosening the lock between the flange (7) and the locking plate (9) the filter, e.g. Applying overpressure to the connector (6) brought into the position shown in Figure II, the with the filter element (1) connected flexible membrane (4) turned inside out. The filter cake is then completely free and can be easily removed. Removal is particularly easy when compressed air is supplied through the nozzle (11) or another gas is blown in. The filter cake is automatically detached and falls into the provided Collecting vessels. If another product is to be filtered, the device can be cleaned very easily v / earth, as all parts that come into contact with the product are freely accessible.

The advantage of the device according to the invention is therefore once in the simple, clean and less labor-intensive handling. On the other hand, the operation is less Prone to failure, as e.g. only one seal is required, which also easily opens each time it is opened possible contamination of the surface or damage can be examined. Also the flexible membrane

(4) can open each time the filter element (1) is extended Damage to be examined. There are also advantages for the production, since the outer jacket (5) on a Page can be tightly closed and so can be manufactured more cheaply.

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The dimensions of the device according to the invention result from the required filter area. Here is the inventive Principle for both filters with relative

The same applies to ρ a small filter area of e.g. only 50 to 100 cm well usable as for larger filters with a filter area of a few square meters.

The one for the outer jacket (5) and the closure plate (9) and the filter element 1 used must have sufficient strength to the when pressing the material

1D filter cake to withstand the pressure that occurs. Since the The outer jacket (5) does not come into contact with the product or with the solvents, for example, a simpler solution is sufficient Steel. In the case of the closure plate (9) it is sufficient that the side facing the solids (3) and filtrate space (2), the come into contact with the product and the solvents, to coat or to clad in such a way that they protect against the substances used is resistant. This can be done e.g. by Plating can be achieved with stainless steel or by enamelling or by coating with rubber or a suitable plastic.

For the flexible membrane (4) all materials previously used in squeeze filters can be used as long as they have good strength with sufficient flexibility and of the common solvents not be attacked. Above all, elastomers such as natural or synthetic rubber are suitable Rubber, such as butyl rubber, silicone rubber or fluorinated rubber. But also other plastics, that meet the above criteria can be used without further ado. As a filter element (1) and seal (8), all materials previously used in filter construction can be used. The inventive Construction does not impose any restrictions on this. The closure of the filter can also be applied to the in the usual way, e.g. with screws, tension clamps or other mechanical or hydraulic ones Closure devices., Ax also automatable if necessary are.

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All materials to be used and special configurations are familiar to the person skilled in the art and can be obtained from be selected according to the respective problem. The features of the invention are provided by does not affect this selection. Materials other than those mentioned here can therefore also be used, e.g. also those that will only be available in the future, provided they have the required properties.

The filter according to the invention can be used both in a horizontal position as well as in a vertical position or any position in between. Which position there is preferred, will primarily depend on the spatial conditions. Usually either the Outer jacket (5) or the closure plate (9) be firmly mounted, while the other part - i.e. at fixed closure plate (9) the outer jacket (5) and vice versa - on a corresponding guide in Is movable in the direction of the longitudinal axis of the filter.

The present invention makes it possible to build squeeze filters that are different from conventional devices have significant advantages in use, are easier and cheaper to manufacture.

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Claims (3)

Pa tuna sayings 1. Squeeze filter, essentially consisting of one tubular filter element in a tubular outer jacket and one between filter element and Outer jacket lying flexible membrane, characterized in that the flexible membrane on the one Side with the inside Fij.ter element and on the other side is connected to the open end of the outer jacket. 2, squeeze filter according to claim 1, characterized in that that one end of the outer jacket is tightly closed. 3. Squeeze filter according to claims 1 and 2, characterized in that the filter in the assembled the inside of the flexible membrane facing the product after the filter element has been extended forms freely accessible outside.