GB2153798A

GB2153798A - Container for granular material

Info

Publication number: GB2153798A
Application number: GB08402967A
Authority: GB
Inventors: Youg Keng Tan
Original assignee: ADKEN ENGINEERING Pte Ltd
Current assignee: ADKEN ENGINEERING Pte Ltd
Priority date: 1984-02-03
Filing date: 1984-02-03
Publication date: 1985-08-29
Also published as: GB2153798B; GB8402967D0

Abstract

A container suitable for the storage or transportation of granular material comprises a vessel (2) having an inner flexible liner (4) of gas retentive material which is secured in a substantially gas tight manner around an upper part (6) of the vessel (2) and which is secured also to a lower region (8) of the vessel (2) thereby to define around the lower region between the vessel (2) and the liner (4) an inflatable enclosure (10), there being at least one gas inlet port (12) in the vessel (2) which serves to facilitate inflation of the enclosure (10) whereby the contents of the container are constrained to gravitate towards the said lower region (8) consequent upon inflation of the enclosure. An aerator (32) may be arranged adjacent the mouth of a discharge pipe (24). <IMAGE>

Description

SPECIFICATION Container This invention relates to containers and more especially it relates to containers suitable for the transportation or storage of granular material.

The term granular material when used herein is intended to include any granular material which can be pneumatically or hydraulically transported or transferred by pipeline and includes fine grain materials such as powders which can readily be blown or sucked along a pipeline with air or with some other fluid.

One of the problems associated with the bulk storage and/or transportation of granular material is the problem of efficiently emptying a container of its contents. This is because granular materials tend to collect in depressions or recesses within containers and accordingly the containers are not easy to empty completely. Thus bulk storage and/or transport containers for granular material must generally to be used for one material only and this is a serious disadvantage especially for transport containers which ideally should be available for use with various granular materials.

It is an object of the present invention to provide a container for granular materials which is relatively easy to empty.

According to the present invention a container suitable for the storage or transportation of granular material comprises a vessel having an inner flexible liner of gas retentive material which is secured in a substantially gas tight manner around an upper part of the vessel and which is secured also to a lower region of the vessel thereby to define around the lower region between the vessel and the liner an inflatable enclosure, and at least one gas inlet port in the vessel which serves to facilitate inflation of the enclosure whereby the contents of the container are constrained to gravitate towards the said lower region consequent upon inflation of the enclosure.

The container may include an outlet pipe for granular material which is arranged in communication with the interior of the container adjacent to the said lower region.

The container may be substantially enclosed and may include an inlet port via which granular material can be introduced.

The container may include aerator means via which gas under pressure can in use tbe passed through the granular material to facilitate flow of the granular material towards the said lower region.

The aerator means may comprise gas inlet ports in the said lower region which communicate with the interior of the container.

The container may be operatively associated with a pneumatic pump arranged to facilitate inflation of the enclosure.

The pump may be arranged also to operate the aerator means.

Some embodiments of the invention will now be described solely by way of example with reference to the accompanying drawings in which: Figure 1 is a somewhat schematic sectional view of a container having an inflatable internal enclosure; Figure 2 is a sectional view of the container shown in Figure 1 with the enclosure partially in flated; Figure 3 is a sectional view of the enclosure shown in Figure 1 with the enclosure fully inflated; Figure 4 is a generally schematic sectional side view of an alternative container having an inflatable enclosure and an aerator means; Figure 5 is a sectional view of the alternative container shown in Figure 4 with the enclosure partially inflated; and Figure 6 is a sectional view of the alternative container with the enclosure inflated to a further extent.

Referring now to Figure 1, Figure 2 and Figure 3, wherein corresponding parts of the Figures bear as appropriate the same numerical designations, an open topped container comprises a substantially rigid vessel 2 having an inner liner 4 of flexible air retentive material e.g. a plastics material, which is bonded in an air tight fashion around an upper portion 6 of the vessel. Although it is desirable that the liner 4 should be substantially air tight, this is not essential and porous or perforated materials such as canvas may be used provided they are sufficiently retentive to facilitate inflation. The liner 4 is similarly bonded to a lower region 8 of the vessel thereby to define between the vessel 2 and the liner 4 an inflatable enclosure 10 which surrounds the lower region 8. The vessel 2 is arranged to include two inlet ports 12 which facilitate inflation of the enclosure 10.

As shown in Figure 1, granular material for storage or transportation in the container is introduced via an inlet port 14, an outlet pipe 16 being provided through which the contents of the container are sucked out. The outlet pipe 16 is arranged to be coupled to a suitable vacuum pump (not shown).

It will be apparent that granular material stored in the container would normally tend to collect in container recesses such as recesses or channels 18 and in order to avoid this so that the container can be substantially completely emptied, the enclosure 10 is progressively inflated during an emptying process so that as shown in Figure 2 and Figure 3 the flexible liner 4 is progressively deformed whereby the contents are constrained to fall towards the lower region 8 so that the granular material can effectively be sucked out of the container via the pipe 16. It will be appreciated that deformation of the liner 4 will start at the top where the contents' weight is least and will progressively extend downwardly so that when the enclosure is fully inflated as shown in Figure 3, the container can be completely emptied of its granular contents.

Referring now to Figure 4, Figure 5 and Figure 6, in this alternative embodiment a container comprises a closed vessel 20 which is filled via a fill pipe 22 with granular material and which is emptied via a discharge pipe 24. In addition to the fill pipe 22 and the discharge pipe 24, a vent pipe 26 is also provided. The vessel 20 is provided with an internal liner 28 of gas retentive material which is secured at a location 30 around an upper wall of the container 20 and which is secured to a lower region 32 thereby to define between the liner 28 and the container 20 an enclosure 34. The enclosure 34 is arranged to be inflatable via an airline 36 and in order to facilitate the flow of granular material contained within the container, an aerator 38 is provided adjacent the lower region 32 which is fed with compressed gas via an aerator pipe 40.Although the gas used will usually be air, for some materials such as coal dust, which represent a fire or explosive risk, some other gas may be used such as an inert gas or carbon dioxide. The pipes 36 and 40 are fed from a compressor (not shown) and a valve 42 is provided whereby a differential air pressure between the pipes 36 and 40 may be maintained as approprate. This is necessary since it may be required to use a different pressure for the aerator 32 than for inflating the enclosure 34.

Various modifications may be made to the arrangements just before described without departing from the scope of the invention and for example a number of inlet ports may be used to inflate the enclosures 34 and 10, and although it is generally desirable that the container comprises a rigid vessel, it may in some embodiments be desirable to utilise a container comprising a flexible vessel.

Although it is envisaged that a container according to the present invention may be particularly suitable for storage or road transport, it is also contemplated that a container according to the present invention may be used in sea or air transportation vehicles and in particular such a container may be used in a barge or a tender, for example for supplying offshore oil rigs.

Claims

1. A container suitable for the storage or transportation of granular material, which container comprises a vessel having an inner flexible liner of gas retentive material which is secured in a substantially gas tight manner around an upper part of the vessel and which is secured also to a lower region of the vessel thereby to define around the lower region between the vessel and the liner an inflatable enclosure, and at least one gas inlet port in the vessel which serves to facilitate inflation of the enclosure whereby the contents of the container are constrained to gravitate towards the said lower region consequent upon inflation of the enclosure.

2. A container according to Claim 1 and including an outlet pipe for granular material which is arranged in communication with the interior of the container adjacent to the said lower region.

3. A container according to Claim 1 or Claim 2 which is substantially enclosed and which includes an inlet port via which granular material can be introduced.

4. A container according to any one of the preceding claims and including aerator means via which gas under pressure can in use be passed through the granular material to facilitate flow of the granular material towards the said lower region.

5. A container according to Claim 4 in which the aerator means comprise gas inlet ports in the said lower region which communicate with the interior of the container.

6. A container according to any one of the preceding claims and operatively associated with a pneumatic pump arranged to facilitate inflation of the enclosure.

7. A container according to Claims 4 and 6 or Claims 5 and 6 in which the pump is arranged also to operate the aerator means.

8. A container suitable for the storage or transportation of granular material, substantially as herein described with reference to the accompanying drawings.