WO2001026769A2

WO2001026769A2 - Fluid contact apparatus

Info

Publication number: WO2001026769A2
Application number: PCT/GB2000/003876
Authority: WO
Inventors: Gerald Victor Horner; Martin Copp
Original assignee: ETA Process Plant Ltd
Current assignee: ETA Process Plant Ltd
Priority date: 1999-10-12
Filing date: 2000-10-09
Publication date: 2001-04-19
Anticipated expiration: 2002-04-12
Also published as: WO2001026769A3; GB9923978D0; GB2355212A; AU7674500A

Abstract

The invention is concerned with a method of providing a fluid contact apparatus at a site, the apparatus comprising a tower (10) in which packing elements (18) are located in random distribution. Provided in the tower above the mass of packing elements is a ceiling plate (20) capable of at least limited movement in a direction longitudinally of the tower. In accordance with the invention, the tower (10) is filled with packing elements whilst the axis of the tower is other than vertical, conveniently being horizontal, or substantially horizontal, and on completion of filling the ceiling plate is moved a short distance to apply a compressive loading on the packing elements, to prevent or restrict movement of the packing elements within the tower. This allows the tower then to be moved to a vertical position, without significant disruption to the packing elements therein.

Description

Title: Improvements relating to fluid contact apparatus Description of Invention

This invention is concerned with improvements relating to fluid contact apparatus, as is used is bio-filtration processes, liquid and gas treatment processes, distillation, condensation and fractional processes, particularly of the kind (hereinafter referred to as being of the kind specified) utilising a fixed tower, in which packing element are located to provide a large surface area with which fluids being processed may come into contact.

A typical apparatus of the kind specified comprises a tower which may be between 1 and 5 metres in diameter, and typically 6 metres in height. Packing elements, which may be of metal or plastics are located in the tower, resting on a perforated floor in a random orientation within the tower.

Where the fluid to be treated comprises a liquid and a gas, typically the liquid may be introduced at or near the top of the tower, and the gas typically introduced at or near the bottom of the tower, the liquid forming a thin film on the surfaces of the packing elements, which film presents a large contact area in relation to its volume, such as to be conducive to mass transfer between the gas and the liquid.

Conventionally the tower is transported to site, conveniently with its longitudinal axis horizontal, such as on a trailer, and is erected on site by being hoisted into a vertical orientation. The packing elements are at that stage introduced into the tower, resting on the perforated floor, and when the tower has been filled to a desired level, a grid is mounted in position above the array of packing elements.

Difficulties are encountered with filling the tower whilst in its vertical orientation. In particular this exercise frequently carried out in the open, and may be affected by adverse weather conditions, and difficulty may be encountered in providing adequate illumination for operative personnel. Additionally, difficulty is experienced in exercising full control over the filling operation, to ensure that optimum filling of the tower with packing elements is carried out. For example, handling machinery for the packing elements which can be used in such circumstances is necessarily portable, enabling it to be transported to site, which places restrictions on the machinery which can be used. Additionally, measuring equipment which may be desirable to ensure optimum filling of the tower may not be available, for such equipment as may be available may be limited in its capability.

Suggestions have been made to load the tower with packing elements whilst in its horizontal orientation, which would permit the tower and packing elements to be transported together to the site, but it has been found that when the tower is moved into its vertical disposition, movement of the packing elements within the tower is caused, causing them to settle somewhat and move from their random distribution, with for example some packing elements nesting within others. This produces an undesired "lay" of packing elements within the tower, and this in turn affects the efficiency of the apparatus.

According to this invention there is provided a method of providing a fluid contact apparatus at a site, in which the tower is moved from a disposition in which its axis is generally horizontal to a disposition in which its axis is vertical whilst containing packing elements, means being provided to apply a longitudinal pressure to the packing elements whereby to prevent any significant movement of the packing elements within the tower during such movement.

Thus the tower may be transported to the site whilst containing the packing elements, significantly reducing transportation costs, and obviating the necessity of providing loading equipment, by which the packing elements may be loaded into the tower, and measuring apparatus, at the site.

Preferably said means is operative to hold the packing elements under sufficient pressure as to cause some resilient deformation of the packing elements, and may be provided by a clamping member, conveniently a perforated clamping member.

Preferably the tower is filled whilst in its horizontal disposition, although for convenience the tower may be inclined at a convenient angle to the horizontal during filling.

Preferably the method involves the use of a hopper, into which packmg elements are deposited, and through which a stream of air flows into the flexible tube which may be inserted into the tower, conveniently through an opening in said clamping member, means being provided to close the opening on completion of filling of the tower.

Preferably means is provided to move the clamping member longitudinally of the tower. Thus on completion of filling of the tower the clamping member may be moved a short distance in the longitudinal direction to compress slightly the packing elements.

If desired, means is provided to withdraw the clamping member longitudinally of the tower, as the tower is filled in this manner, a more controlled filling of the tower may be obtained.

There will now be given a detailed description, to be read with reference to the accompanying drawings, of a method of providing a fluid contact apparatus at a site, which method has been selected for the purposes of illustrating the invention by way of example.

In the accompanying drawings:

FIGURE 1 is a view of the fluid contact apparatus inserted on site.

FIGURE 2 is a view illustrating the filling of the tower of the apparatus with packing element; and

FIGURE 3 is a view showing a device for transporting packing elements from a store thereof into the tower.

The apparatus with which the illustrative method is concerned is a fluid contact apparatus, comprising a tower 10 which may typically be 2.7 metres in diameter, and may be 6 metres in height, the tower comprising fluid inlet/outlet pipers schematically indicated by the numerals 12, 14, and being used with its axis substantially vertically.

The tower comprises, approximately one quarter of the way up, a perforated floor plate 16, on which a mass 18 of packmg elements are located in random distribution. The packing elements may be of a variety of sizes and shapes, typically being cylindrical or part cylindrical, having an axial length of between 30mm and 50mm, and a diameter of perhaps 25mm, being provided with a variety of openings and tangs to increase contact capability.

Conventionally provided in the tower 10 above the mass 18 of packing elements is a perforated ceiling plate 20. However in the preferred embodiment, the ceiling plate is capable of at least limited movement in a direction longitudinally of the tower, specifically from a rest position to an operative position, such movement being in the order of 100mm to 150mm in magnitude.

In accordance with this invention the cylinder 10 is filled with packing elements whilst the axis of the tower is other than vertical, conveniently being horizontal or substantially horizontal.

The filling of the tower conveniently involves the use of an apparatus of the kind illustrated in Figure 3, comprising a blower 30, having an air inlet 32 and an air outlet 34, across which random packing elements may be dropped through a hopper 36, conveniently being introduced into the hopper mechanically, such as by the use of a conveyor having a variable drive speed. Conveniently connected to the outlet 34 is an elongate delivery hose 40, which may be taken by an operator into the interior of the tower 10.

The device 30 is switched on and packing elements are delivered through the hose to the interior of the tower, conveniently whilst the tower is in a horizontal position, such as on a trailer for subsequent road transportation. As the space between the floor plate 16 and the ceiling plate becomes filled with packing elements, on completion of filling of the tower the opening

24 in the ceiling plate may be closed, and the ceiling plate 20 moved towards the floor plate 16, to apply a small compressive loading on the packing elements. Since the clamping elements are conventionally of thin-wall construction, and are of metal or plastics material, they are capable of being resiliently deformed, and such reverse axial movement of the ceiling plate 22 places the packing elements under an axial loading, reducing tendency of the packing elements to move, during subsequent transportation to site, and movement of the tower into its vertical orientation.

Thus, the ceiling plate provides the function of a clamping means of the tower.

By the use of the invention above described, a number of industrial advantages may be obtained: a) the tower may be filled with packing elements conveniently at the site at which they are constructed, enabling the tower to be filled with packing elements under more controlled conditions than are capable of being employed subsequent to the transportation of the tower to site, and subsequent to the movement of the tower to its final vertical disposition. b) the tower may be filled at a higher rate than has heretofore been practical, specifically up to a rate of 10m /hour. c) the capability of engineers gaining access to the tower during filling allows greater control to be exercised over the filling operation, than when the tower is in its final vertical position, when access to the tower is generally not possible. d) testing equipment may be introduced into the tower whilst in its horizontal disposition, to ensure that optimum packing densities are obtained, permitted remedial action to be taken in the event that a problem is encountered in the introduction of the packing elements into the tower; e) filling may be accomplished under cover; and f) machinery may be utilised, such as the device illustrated in Figure 3, for the introduction of the packing elements into the tower, without the need to transport the machine to site.

In the present specification "comprise" means "includes or consists of and "comprising" means "including or consisting of.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

1 A method of providing a fluid contact apparatus at a site, in which a tower is moved from a disposition in which its axis is generally horizontal to a disposition in which its axis is generally vertical whilst containing packing elements, means being provided to apply a longitudinal pressure to the packmg elements, whereby to prevent any significant movement of the packing elements within the tower during such movement.

2 A method according to claim 1 wherein in the tower is transported to the site whilst containing the packmg elements.

3 A method according to one of claims 1 and 2 wherein said means is operative to hold the packing elements under sufficient pressure as to cause some resilient deformation of the packmg elements.

4 A method according to claim 3 wherein said means is provided by a clamping member.

5 A method according to claim 4 comprising means to move the clamping member longitudinally of the tower.

6 A method according to claim 5 wherein the clamping member is moved a short distance in the longitudinal direction to compress slightly the packing elements on completion of filling of the tower.

7 A method according to any one of the preceding claims wherein the tower is inclined at a convenient angle to the horizontal during filling. 8 A method according to any one of the preceding claims in which the method involves the use of a hopper, into which packing elements are deposited and through which a stream of air flows into a flexible tube, which may be inserted into the tower.

9 A method of providing a fluid contact apparatus at a site, when carried out substantially as hereinbefore described with reference to the accompany drawings.

10 A fluid contact apparatus, comprising an elongate generally vertical tower containing a plurality of randomly disposed packing elements, in which the packing elements are retained under an axial load by a longitudinally- moveable clamping member in the tower.