MXPA97006646A - Apparatus for filtering and coalescer liqui - Google Patents

Abstract

The present invention relates to an apparatus for removing contaminants from a liquid and for the coagulation of droplets of a liquid dispersed in another immiscible liquid, the apparatus comprises a box divided into two compartments by an essentially tubular fibrous filter, the fibrous filter is formed by groups of fibers joined at one end by an end support, there is a liquid inlet leading to one side of the fibrous filter and a liquid outlet leading to the other side of the fibrous filter, the end supports can be moved axially one with relationship to the other and can rotate relative to each other around the longitudinal axis of the tubular fibrous filter, characterized in that there is a cage unit, which comprises a plurality of rings located within the fibrous filter adapted to support the fibers that form the fibrous filter whose cage structure is not attached to at least one of the extremities

Description

APPARATUS FOR FILTERING AND COALESCER LIQUIDS The present invention relates to an apparatus for filtering liquid solids for the coalescence of droplets of a liquid dispersed in another liquid. EP 207797 describes an apparatus for removing contaminants from a liquid. The apparatus comprises fibers connected at each end to end supports, which can move away from or towards each other to place the fibers under tension or to relax any applied tension. The end supports can also be rotated in relation to the other. The fibers are attached to the end supports to form a fiber tube surrounding the central tubular filter provided with perforations. The liquid to be treated passes through the fibers between the central core and an outer compartment surrounding the fibers. In use, the end supports move towards each other and rotate in mutual relation to twist the fibers and compress them against the perforated tube. A disadvantage of using perforated tubes is that they can impose a restriction on the flow through the apparatus thus leading to an increase in pressure drop if the flow velocity is sustained. EP 360601 describes an apparatus for removing contaminants from liquids, which treats this problem using REF: 25586 a helical spring to provide adequate support for the tubular fibrous filter both during use and during the washing process to remove impurities from the apparatus. The radial resistance of the coil spring is sufficient to support the fibers against the force exerted by the pressure difference in the bed of fibers forming the tubular filter when they contract under the torsional stress applied by the relative rotation of the fiber of the end supports . However, with larger sized equipment with larger flow rates, the necessary spring resistance requires that it be made of a wire of such a size that the weight of the wire makes it unsuitable. This is because, when the diameter is increased for a greater flow rate, the radial force on the spring increases to the square of the diameter, thus when the size is increased the design of the spring becomes uneconomical. To overcome such problems, the coil spring could be made of tubular design or made of lighter materials. However, this could result in a substantial increase in manufacturing costs. In practice, springs with diameters greater than 250mm can not be used. With this structure the rotation of the ends against the torsion of the spring is always in the same direction, so that the fibers twist in the same direction about the longitudinal axis of the apparatus. This can be advantageous in the countercurrent washing process. It may therefore be desirable to provide an apparatus that overcomes the above disadvantages and has sufficient radial resistance to allow filtration and coalescence to be effected at a higher liquid flow rate in an economical and efficient manner. In addition, a more rigorous counter-current washing routine is now imposed on the filter elements in order to have a greater efficiency of backwashing. With the increase of resistance to backwashing there is a much greater tension on the support and it has been found that with a spring as support there is the danger of fatigue failure. It has now been found that replacing the coil spring with a cage configuration provides an apparatus that overcomes the disadvantages of the coil spring mentioned above. The apparatus of the present invention can also be used as a coalescence device to cause droplets or droplets of a liquid to disperse in another immiscible liquid for coalescence and thus to separate more easily. The coalescence devices are used to separate hydrocarbon oils from water, although they have been used to separate many other dispersions comprising two substantially immiscible liquids. The present invention provides an apparatus which can be used to remove contaminants from a liquid and for the coalescence of droplets of a liquid dispersed in another immiscible liquid, which apparatus comprises a frame divided into two compartments by a substantially tubular fibrous filter, the filter fibrous is formed by fibers attached at each end to an end support, there is a liquid inlet leading to one side of the fibrous filter and a liquid outlet leading from the other side of the fibrous filter, the end supports move axially in relation mutually and rotate in mutual relation about the longitudinal axis of the tubular fibrous filter, there is a cage assembly comprising a plurality of rings located within the fibrous filter adapted to support the fibers forming the fibrous filter. The cage assembly is preferably in contact with the fibers that form the fibrous filter to support the fibers to resist inward movement of the fibers caused when the end supports move axially relative to each other and rotate to torque the fibers; this movement tends to close the compartment surrounded by the tubular filter.

One of the end supports is preferably connected to a control rod so that the end support can be moved axially towards and away from the other end support. This control rod can also rotate the end support to which it is connected in relation to the other end support, around the longitudinal axis of the tubular fibrous filter. The cage assembly may consist of a series of rings, preferably arranged along a common axis. Optionally, the rings can be attached to any end support or remain unconnected. The cage may comprise one or more sets of rings connected together; in one embodiment the cage comprises two parts, each part consisting of a plurality of rings, which are connected to a different end support, so that the end supports move close or apart, the two parts of the cage also move close to or separated. The spaces between the rings are preferably at a distance to give adequate support to the fibers without a very large effect on the flow of the liquid through the filter element when the equipment is in operation. The rings forming the cage are preferably of the same diameter and can be made of any suitable material, for example stainless steel; optionally the rings may be of a hollow tubular construction. The rings forming the cage structure can, if necessary, be placed in position by means of radially located supports and / or longitudinally arranged supports can be used. In one embodiment of the invention, the cage structure comprises two parts, each part consists of several rings and can be of the same or different length. Each part is attached to a different end support. The control rod can move the end support of the apparatus, to which it is connected, towards the other end support, so that the first part of the cage assembly attached to this end support also moves towards the second part of the cage assembly . In this position, the apparatus is in position for filtration, providing a packed fibrous array. The cage assembly provides full support to the tubular filter. Preferably, the second part of the cage assembly is fixed by an attachment to the end support of the opposite apparatus to be connected to the control rod. In use, the end supports are placed in their operating position with the fibers supported on the cage to form the fibrous filter. The liquid passes through the inlet through the fibers acting in a conventional manner. When countercurrent washing of the filter element is desired, the end supports move away from each other and the fibers are untwisted. This movement of the end supports increases the spaces between the cage or part of the cage and one or more end supports (depending on which end support the cage or parts of the cage are attached to), thus allowing greater flow of liquid. The liquid then passes through the filter element in the opposite direction (ie through the outlet and out through the inlet) to backwash the filter element and remove contaminants on the fibers. In use, the filter apparatus according to the present invention is operated in the general manner described in EP 360601. A specific embodiment of the present invention will now be illustrated with reference to the accompanying drawings in which: Figure 1 is a cross section through an apparatus, according to the invention shown in packaged configuration.

Figure 2 is in the fully extended position and. Figure 3 is an alternative embodiment of the invention in extended position. The apparatus comprises a frame (1) divided into two compartments by means of a tubular fibrous filter indicated as (2). The fibrous filter comprises bundles of fibers secured to each of the end-to-end supports (3) and (4). The end support (3) is fixed to the frame path (5). The end support (4) is attached to a control rod (6) to allow it to move axially towards the end support (3) and to rotate in relation to the end support (3). A liquid inlet is provided (7) in the opening of the frame (1) towards the compartment surrounding the tubular filter. A liquid outlet (8) is provided at the base of the frame opening to the compartment located within the tubular filter. A cage structure comprising a number of circular rings (13) is located within the tubular filter and comprises two parts, a fixed part (10) and a moving part (eleven) . The fixed part (10) is attached to the end support (3).

The mobile part is attached to the end support (4) and can move towards and away from the fixed part by means of the control rod (6). Alternatively the cage structures (10) and (11) are not fixed to the end supports (3) and (4), but are in the form of a "floating cage", as shown in Figure 3. In the position shown in Figure 1, the moving part (11) has been moved so that the space (12) between the two parts is substantially equal to the spaces between the circular rings (13), which each form part of the the cage structure. The filter apparatus is now packaged in the proper position for filtering the position shown in Figure 2, the space (12) has been increased by moving the part (11) away from the part (10) and the filter apparatus is in its fully extended position suitable for backwashing.

It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects that it refers. Having described the invention as above, property is claimed as contained in the following:

Claims (13)

1. An apparatus, which can be used to remove contaminants from a liquid and for the coalescence of droplets of a liquid dispersed in another immiscible liquid, which apparatus is characterized in that it comprises a framework divided into two compartments by a substantially tubular fibrous filter, the Fibrous filter is formed by fibers joined at each end to an end support, there is a liquid inlet leading to one side of the fibrous filter and a liquid outlet leading to the other side of the fibrous filter, the end supports move axially in mutual relation and rotate in mutual relation about the longitudinal axis of the tubular fibrous filter, there is a cage assembly comprising a plurality of rings located within the fibrous filter adapted to support the fibers forming the fibrous filter.

2. The apparatus according to claim 1, characterized in that the cage assembly is in contact with the fibers the fibrous filter to support the fibers to resist the inward movement of the fibers caused when the end supports move axially towards each other and rotate to torser the fibers.

3. The apparatus according to claim 1 or 2, characterized in that the end supports are connected to a control rod, which can move this end support axially towards and from the other end support and rotate this end support around the longitudinal axis of the fibrous tubular filter.

4. The apparatus according to any of claims 1 to 3, characterized in that the cage assembly comprises a series of rings arranged along a common axis.

5. The apparatus according to claim 4, characterized in that the rings are connected to an end support.

6. The apparatus according to claim 4, characterized in that the rings are not connected to any end support.

7. The apparatus according to any of claims 1 to 6, characterized in that the cage comprises at least one set of rings comprising a plurality of rings connected to each other.

8. The apparatus according to claim 7, characterized in that the cage comprises two sets of rings.

9. The apparatus according to claim 8, characterized in that the ring set is connected to a different end support so that the end supports move closer or further apart, the two parts of the cage also move closer or further apart.

10. The apparatus according to claim 8, characterized in that none of the ring sets are connected to an end support.

11. The apparatus according to any of claims 4 to 10, characterized in that the spaces between the rings in each set are of a distance to give adequate support to the fibers without a very large effect on the flow of liquid through the filter element when the equipment is in operation.

12. The apparatus according to any of claims 4 to 10, characterized in that the rings forming the box structure are placed in their position by means of radially and / or longitudinally arranged supports.

13. The apparatus according to claim 1, characterized in that it is as described above with reference to the drawings.