GB2157189A

GB2157189A - Tower packing element

Info

Publication number: GB2157189A
Application number: GB08409651A
Authority: GB
Inventors: Max Leva
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-04-13
Filing date: 1984-04-13
Publication date: 1985-10-23
Also published as: DE3513930C2; GB2157189B; DE3513930A1; GB8409651D0

Abstract

The element has a base of strip form bent to define two straight limbs (1, 2) connected by an intermediate curved portion (3) which may be of small or large radius. One or both of the limbs is provided with at least one slot (5) and a respective tongue (4) depending from one end of the slot. The length (L) of each limb ideally lies in the range W>L>W/3, where W is the width of the limb. The element may be of plastics or metal. <IMAGE>

Description

SPECIFICATION Tower packing element This invention relates to a tower packing element for use in random poured packed beds on towers and columns, to bring about mass and heat transfer in for example gas absorbtions, distillation, reactors and similar apparatus used in chemical and physical operation.

According to the invention a tower packing element intended for a random poured packed bed comprises a base of strip form shaped to define two substantially straight limbs connected by a intermediate curved portion, a slot in one of the limbs, and a tongue displayed from the plane of said one limb and depending from one end of the slot, the included angle between the planes of the limbs lying in the range substantially 5 to substantially 1600.

Such an element may be produced from plastics but it is preferably produced from metal sheet by cutting and bending the sheet. When the element is made of plastics the usual methods of injection moulding or other forming methods may be employed. The straight limbs facilitate the use of simple tools in the forming process.

Preferably the included angle lies in the range substantially 20 to substantially 140 , but most preferably said angle is in the range substantially 30 to substantially 1200.

The tongue preferably extends into the space between the two limbs, that is generally towards the other limb, but if desired the tongue may be arranged to extend outwardly of said one limb, that is generally away from the other limb.

A plurality of slots with associated tongues are preferably arranged in rows in the limbs only, the rows extending substantially longitudinally of the base.

The metal strip prior to bending and cutting is preferably of substantially rectangular outline, the bending to define the bent portion then being about an axis extending substantially transversely of the strip.

The curved portion is preferably in the form of a progressive bend rather than in the form of a local fold but a local fold might be employed.

The curved portion may be circular, elliptical, parabolic, hyperbolic or any combination thereof.

When the curved portion is circular, the radius of curvature of the curved portion is preferably in the range substantially 1/4" to substantially 4" and most preferably in the range substantially 1/2" to substantially 3".

The limbs may be of equal or unequal lengths.

The provision of limbs of unequal lengths would be of advantage in some circumstances since it enables an extra random factor to be incorporated in a bed of the elements.

The length L of each limb preferably lies in the range 3W > L > W/6 where W is the width of each limb, and most preferably W > L > W/3.

Each limb may be substantially flat, but it may be formed with indentations, corrugations and/or a peripheral flange in order to improve the strength of the element to resist compaction. Thus, in a preferred arrangement each limb is of shallow trough shape in transverse cross-section, side walls of the trough being defined by peripheral flanges on the limbs which are directed outwardly of the element, that is in the direction generally away from the other limb.

At least one tongue preferably extends substantially to that plane which includes the free ends of both limbs, so as to assist in preventing stacking of the elements.

The limbs and/or when the intermediate portion is progressively curved, the intermediate portion may be provided with perforations may be round or oval.

The free margins of the limbs and/or of one or more tongues may be provided with teeth to provide points of contact between adjacent elements in the bed or liquid drip points.

Some packing elements for a random poured packed bed in accordance with the invention will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a schematic side elevation of a first packing element; Figure 2 is a view looking in the direction of the arrow A in Figure 1; Figure 3 is a schematic side elevation of a second packing element having limbs of unequal length; Figures 4, 5 and 6 are side elevations of a third fourth and fifth packing elements; Figure 7 is a view looking in the direction of the arrow B in Figure 6; Figure 8 is a view similar to Figure 6 but of a modification; Figure 9 is a cross-section on the line 9-9 of Figure 8; and Figure 10 is a view similar to Figure 6 of another modification.

With reference to Figures 1 and 2, an oblong rectangular strip of sheet metal has been bent and cut to define a pair of straight limbs 1, 2 of equal length L and width W connected at 3 by a transverse fold line. An inwardly directed curved tongue 4 has been struck out from the material of limb 1 to leave a complementarily shaped longitudinally extending slot 5 in limb 1, the slot 5 terminating 6, short of the fold line 3 at 6. An angle a is included between the limbs 1, 2, which in this case is about 77 . It is contemplated, however, that the angle a may be any angle within the range substantially 5 to substantially 1600. The limbs 1, 2 and fold 3 constitute the base of the packing element.

The ratio of the length L of the limbs 1, 2 to the width W of the limbs is in this case UW = 7/5 but any convenient ratio for UW may be chosen to meet a particular application. It is preferred that 3W > L > W/6.

In the modified element of Figure 3 the limbs 1, 2 are made of unequal lengths, and this element includes the further modification that each limb 1, 2 may be provided with one or more slots and depending tongues. In this case limb 1 carries the single tongue 4, and limb 2 the single tongue 7, both of which extend into the space between limbs 1, 2 in order to restrict the interpenetration of one packing element with another in the packed bed.

Figure 4 shows a third element which shows further features which differ from the basic form of Figure 1. A first difference is that instead of a sharp fold connecting the limbs 1, 2 they are connected by a progressively curved portion 3' of radius R, the included angle a being defined in this case as shown in the drawing. A second difference is that the tongues 4, 7 have been made longer, this being facilitated by arranging the slots such that they extend closer to the free ends of the limbs 1, 2. The longer slots enable the tongues 4, 7 to be bent to bring their free ends adjacent to that plane C that connects the free ends of limbs 1, the advantage of this arrangement being that interpenetration and stacking of the elements is further inhibited. Each limb 1, 2 is provided with a further slot and associated tongue 12, 13.Thus the base is provided with two transversely spaced rows of slots, and it should be noted that the slots are in the limbs 1, 2 only and not in curved portion 3'.

Figure 5 shows an arrangement in which the limbs 1, 2 are not only provided with inwardly directed tongues 4, 7 but also with outwardly directed tongues 8, 9. It will be noted that in this case the tongues 4, 7 depend from the limbs 1, 2 at positions adjacent to their connected ends, and accordingly tongue 4 in this case extends in a rather different direction from the corresponding tongue 4 in Figure 1.

Figures 6 and 7 show a further element in which the strip is provided with two rows of slots, the slots extending longitudinally of the strip, and the rows being spaced apart transversely of the strip.

Each limb is provided in this case with a slot 10 staggered longitudinally of the limb with respect to a slot 11, the tongues 4 and 7 depending from the ends of the slots 10 that are towards the curved portion 3', and the tongues 12 and 13 depending from the ends of slots 11 that are towards the free ends of the limbs 1, 2.

The base of the element of Figures 6 and 7 is of shallow trough shape in transverse cross-section, the sides of the trough shape being defined by peripheral outwardly directed flanges 14 which extend along the entire lengths of the limbs 1 and 2 and along the curved portion 3'. The flanges 14 provide substantial rigidity to the element. The free ends of the limbs 1, 2 are provided with teeth 15 for the purposes previously described.

Figures 8 and 9 show a modification of the element of Figure 6 in which the base is provided along one longitudinal edge with an outwardly di rected flange 14 and along the opposite longitudi nal edge with an inwardly directed flange 14'. This provides an additional random factor to a bed of the elements.

The curved portion 3' of the elements of Figures 4 to 8 are circular, but in Figure 10 an element is shown having a curved portion 3' of elliptical shape.

Claims

1. A tower packing element intended for a random poured packed bed comprising a base strip form shaped to define two substantially straight limbs connected by an intermediate curved portion, a slot in one of the limbs, and a tongue displaced from the plane of said one limb and depending from one end of the slot, the included angle between the planes of the limbs lying in the range substantially 5 to substantially 1600.

2. An element as claimed in claim 1 in which the included angle lies in the range substantially 20 to substantially 140".

3. An element as claimed in claim 2 in which said angle is in the range substantially 30 to substantially 1200.

4. An element as claimed in any one of the preceding claims in which the tongue extends into the space between the two limbs.

5. An element as claimed in any of the preceding claims in which a plurality of slots with associated tongues are arranged in rows in the limbs, the rows extending substantially longitudinally of the base, the curved portion being without slots with associated tongues.

6. An element as claimed in any of the preceding claims in which the curved portion is part-circular, the radius of curvature of the curved portion being in the range substantially 2" to substantially 4".

7. An element as claimed in any of the preceding claims in which the length L of each lies in the range 3W > L > W/6 where W is the width of each limb.

8. An element as claimed in any of the preceding claims in which each limb is of shallow trough shape in transverse cross-section, side walls of the trough being defined by peripheral flanges on the limbs which are directed outwardly of the element, that is in the direction generally away from the other limb.