GB2345721A

GB2345721A - A silo comprising separate containers for liquid and dry materials

Info

Publication number: GB2345721A
Application number: GB9900666A
Authority: GB
Inventors: David Kevan
Original assignee: TARMAC UK Ltd; Tarmac Heavy Building Materials UK Ltd
Current assignee: TARMAC UK Ltd; Tarmac Heavy Building Materials UK Ltd
Priority date: 1999-01-14
Filing date: 1999-01-14
Publication date: 2000-07-19

Abstract

A silo 10 comprises a container 14 for dry material to be wetted for use having an outlet 19 at or towards an end 18 of the container 14, whereby the dry material can flow from the container 14 substantially under gravity, characterised in that the silo 10 includes a tank 22 for liquid, maintaining the liquid separate from the dry material. The tank 22 comprises means 30, 31 to fill the tank 22 with the liquid from an external source and means to deliver the liquid to a position at or adjacent the outlet 19 from the container 14 for the dry material for mixing with the dry material. The container 14 and tank 22 may be filled at a depot and then transported, alleviating the need for a water supply on site.

Description

PATENTS ACT 1977 DJL/A9699GB Title: Improvements in or Relating to Silos Description of Invention This invention relates to a silo by which we mean a structure including a container for storing in bulk dry material which it is required to be wetted for use. More particularly the invention relates to a silo for storing in bulk dry mortar ingredients for use in building.

Typically such silos contain blended together mortar ingredients in dry form. Typically such silos are mobile and are filled with the dry material at a mixing plant, and then delivered e. g. on a lorry to the building site where the silo is erected. When the dry material is required for use, the material is gravity fed to an outlet from the container to a mixer, such as a screw mixer mounted usually beneath the silo, where water is added to produce mortar for use.

Such silos may be used satisfactorily where there is an adequate water supply available. By"adequate"we mean that a constant water supply at an adequate pressure is required in order that sufficient water can be available for mixing with the dry mortar ingredients to produce a batch of mortar for use.

Particularly where the mortar is required to produce a flowing floor screed, the rate of production of the screed is largely governed by the available water volume, and thus on building sites where there is an inadequate or unreliable water supply, it is not possible to produce screed at a sufficient rate for economic use.

On some building sites no water is available at all, which means that to produce any mortar at all, it is necessary to deliver water to the building site e. g. in a tanker lorry, which can be costly.

It has been proposed to provide on site, a water tank. To provide an adequate water pressure for use in mixing with dry material from a silo, the tank has been elevated e. g. by placing the tank on a site cabin adjacent to the silo.

According to a first aspect of the invention we provide a silo comprising a container for dry material to be wetted for use, the container having an outlet for the dry material at or towards an end of the container which in use is at the bottom, whereby the dry material can flow from the container when the outlet is opened, under gravity or substantially under gravity, characterised in that the silo includes a tank for liquid, the tank maintaining the liquid separate from the dry material, the tank having means to fill the tank with the liquid from an external source, and means to deliver the liquid from the tank to a position at or adjacent the outlet from the container for the dry material for mixing with the dry material.

Thus by virtue of the present invention, there is no need to provide a tank separate to the silo, or to install such separate tank on site. The tank may be filled on site and/or delivered to site in a full condition, but in each case a plentiful supply of liquid for mixing with the dry material can be made readily available.

Preferably the tank is positioned towards the top of the container in use so that the liquid which is delivered to the position adjacent the container outlet at an adequate pressure for use.

In one embodiment the silo has a container wall which extends from the top to the bottom end of the silo, there being a dividing wall within the silo so that a lower silo part is separated from an upper silo part, the lower part being the container for the dry material, and the upper part being the tank for the liquid. Thus the tank is integral with the container.

In another embodiment the tank need not be integral with the container but may be mounted by a superstructure on the container. Thus the tank may for example be a plastic tank.

In another embodiment, the silo may include a frame structure which may mount both the container and the tank.

In each case the means to fill the tank may include a coupling, preferably a quick release coupling, to which an external conduit may be connected, and the means to deliver the liquid to the position adjacent the outlet may include a delivery conduit which may extend internally or externally of the container and may include a liquid delivery control means such as a valve.

Particularly where the silo is for storing bulk material such as dry mortar ingredients or other building material which has to be mixed with water for use, the silo may have an integral mixing means at or adjacent the outlet from the container and to which the means to deliver the liquid may deliver the liquid.

According to a second aspect of the invention we provide a method of providing a liquid supply for mixing with dry material stored in a silo according to the first aspect of the invention, including the steps of introducing liquid into the tank at a depot, introducing the dry material into the container at the or another depot, transporting the silo to site and erecting the silo so that the tank containing the liquid is above the container.

The tank and/or the container of the silo may be filled with the silo in a first orientation where the, in use, top and bottom ends are at the sides, or with the silo in its in use orientation, with the silo upright with the top end at the top and the bottom end at the bottom.

The invention will now be described with reference to the accompanying drawings in which: FIGURE 1 is a diagrammatic side view of an embodiment of a silo in accordance with the invention; FIGURE 2 is a diagrammatic plan view of the silo of figure 1.

Referring to the drawings there is shown a silo 10 for storing bulk materials, in this case bulk building material such as mortar ingredients, in a dry condition. The dry material is mixed with liquid i. e. water for use, in a mixing means 12 which in the example shown, is a screw mixer but could be an alternative kind of mixer if required, or if desirable to suit particular dry material and liquid mixes. The water may contain additives suitable for the mortar or other mix, if desired.

The silo comprises a container 14 for the bulk dry ingredients, which container 14 in this embodiment has a generally cylindrical wall 13 and a top end 15 which has a lifting hook 16 by means of which the container 14 may be lifted and manoeuvred e. g's by a crane or lifting gear of the silo delivery vehicle, into a suitable position e. g. on a building site, and a bottom 18 of typically conical shape to aid the flow of the dry ingredients from an outlet 19 of the container 14 under gravity.

The container 14 is typically made of steel or another strong material so that the silo 10 has substantial mechanical strength and may be lifted even when the container 14 is full, by the lifting hook 16. In another embodiment though, the container 14 may be less robust and may be mounted in a frame which supplied mechanical strength to the silo 10.

In the example shown though, the container 14 is supported on the ground by a support frame 20 which includes four legs 21 which are connected to the container wall 13, and ground engaging struts 22 between pairs of the legs 21.

Thus the silo 10 in use is in a generally upright condition with the top end 15 at the top and the opening 19 at the bottom.

In accordance with the invention, to provide an adequate water supply for mixing with the dry ingredients, there is provided a water tank 22. In the present example, the tank 22 is positioned above the top 15 of the container 14 and is supported by a superstructure 25 which is secured to the container wall 13. The superstructure 25 may comprise a ring 26 e. g. of"L"configuration, which follows the circumferential join between the cylindrical wall 13 and the top 15 of the container 14, and a frame of three or four legs 27 interconnected with struts (not seen) as necessary to achieve the necessary mechanical strength.

The legs 27 may be connected at their ends remote from the ring 26 by a top frame 29 or alternatively a lid.

The tank 22 may conveniently be a plastic tank which has an enclosed hollow for storing the water. A liquid inlet 30 is provided to enable the tank 22 to be filled as hereinafter described, and the inlet may terminate in a coupling 31 which may permit the ready connection of the inlet to a water supply. The inlet 31 may include a liquid level control means such as a ball cock 32 where for example the inlet 30 is connected on site to a water supply.

The tank 22 further comprises a water outlet 33 which comprises a delivery conduit which extends from the tank 22 downwardly to the mixing means 12 i. e. to a position adjacent the opening 19 from the container 14 for the dry material. Along the delivery conduit 33, e. g. at the mixing means, a valve 34 is provided whereby the flow of water along the conduit 33 may be controlled.

It will be appreciated from figure 2 that the tank 22 is shaped to included an access opening 35 which is segment shaped in the example, to permit of access to the lifting hook 16. However, if the superstructure 25 mounting the tank 22 is sufficiently strong, if desired alternatively a lifting hook 16a may be provided on the superstructure 25 above the tank 22 in the position shown in dotted lines in figure 1.

A typical silo 10 may contain between 18 and 22 cubic metres of dry material when full, and may require 100 to 300 litres of water per cubic metre of dry material, for mixing. Thus for the tank 22 to contain sufficient water for mixing with all the dry material in the container 14, the tank requires a capacity of up to about 6600 litres. To achieve this the tank 22 may have dimensions of say, 0.4 to 1. 34 metres in height, and a radius approaching that of the container 14.

Of course other silos may have varying dimensions and these figures are given for example only.

In another embodiment, instead of the tank 22 being supported and mounted by a superstructure 25 above the container 14, where the silo has a frame structure for the container 14, the tank 22 may be supported by the frame structure which may be appropriately configured.

In another embodiment, instead of providing a plastic or similar tank 22 outside the envelope of the container 14, the tank 22 may be provided within the container 14. The tank 22 may again be a plastic or other self contained tank 22 which may be above the dry material or at least partially surrounded by the dry material, or alternatively, the container 14 may have a dividing wall dividing the container into upper and lower parts, the upper part containing liquid for mixing with the dry material contained in the lower part. The upper part may be lined, but in any event great care would need to be taken to ensure that the dry and wet materials stored in the container 14 are kept separate.

In each embodiment, the delivery conduit 33 for the liquid need not extend to the position at or adjacent the outlet 19 for the dry material, exteriorly of the container 14, but may extend downwardly through the container 14.

The container 14 may be filled with the dry material at a depot, via a fill pipe 40. The tank 22 may too be filled at the depot or another depot. The silo 10 may then be transported, usually in a horizontal condition with the in use bottom end 18 at one side and the in use upper end 15 at another side, e. g. on a lorry, to site where the silo 10 may be erected into the upright condition shown in figure 1.

Alternatively the silo 10 may be deliver and erected empty, or at least the tank 22 may be empty, and filled on site with a sufficient quantity of water to produce a desired quantity of mortar or other wet mixture for use. Thus a water supply independent of the site water supply, if there is one, is conveniently provided.

It will be appreciated that to assist the free flow of the dry material from the container a vent 42 is provided, and that to permit the enclosed tank 22 to be filled and to empty, a vent would be required.

In another arrangement, the fill conduit 30 and delivery conduit 33 may be provided by a common conduit, although then could not be used simultaneously.

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 utilise for realising the invention in diverse forms thereof.

Claims

CLAIMS 1. A silo comprising a container for dry material to be wetted for use, the container having an outlet for the dry material at or towards an end of the container which in use is at the bottom, whereby the dry material can flow from the container when the outlet is opened, under gravity or substantially under gravity, characterised in that the silo includes a tank for liquid, the tank maintaining the liquid separate from the dry material, the tank having means to fill the tank with the liquid from an external source, and means to deliver the liquid from the tank to a position at or adjacent the outlet from the container for the dry material for mixing with the dry material.
2. A silo according to claim 1 characterised in that the tank is positioned towards the top of the container in use.
3. A silo according to claim 1 or claim 2 characterised in that the silo has a container wall which extends from the top to the bottom end of the silo, there being a dividing wall within the silo so that a lower silo part is separated from an upper silo part, the lower part being the container for the dry material, and the upper part being the tank for the liquid.
4. A silo according to claim 1 or claim 2 characterised in that the tank is mounted by a superstructure on the container.
5. A silo according to claim 1 or claim 2 characterised in that the silo includes a frame structure which mounts both the container and the tank.
6. A silo according to claim 4 or claim 5 characterised in that the tank is a plastic tank.
7. A silo according to any one of the preceding claims characterised in that the means to fill the tank includes a coupling to which an external conduit is connectable.
8. A silo according to any one of the preceding claims characterised in that the means to deliver the liquid to the position adjacent the outlet includes a delivery conduit.
9. A silo according to claim 8 characterised in that the delivery conduit extends internally of the container.
10. A silo according to claim 8 characterised in that the delivery conduit extends externally of the container
11. A silo according to any one of claims 8 to 10 characterised in that the delivery conduit includes a liquid delivery control means.
12. A silo according to any one of the preceding claims characterised in that the silo has an integral mixing means at or adjacent the outlet from the container and to which the means to deliver the liquid may deliver the liquid.
13. A silo substantially as hereinbefore described with reference to and as shown in the accompanying drawings.
14. A method of providing a liquid supply for mixing with dry material stored in a silo according to any one of the preceding claims, including the steps of introducing liquid into the tank at a depot, introducing the dry material into the container at the or another depot, transporting the silo to site and erecting the silo so that the tank containing the liquid is above the container.
15. A method according to claim 14 characterised in that the tank and/or the container of the silo is filled with the silo in a first orientation where the, in use, top and bottom ends are at the sides, or with the silo in its in use orientation, with the silo upright with the top end at the top and the bottom end at the bottom.
16. A method of providing a liquid supply for mixing with dry material stored in a silo substantially as hereinbefore described with reference to the accompanying drawings.