GB2581982A

GB2581982A - An improved system for conveying particulate material

Info

Publication number: GB2581982A
Application number: GB1902966.9A
Authority: GB
Inventors: Walker Kevin
Original assignee: Priden Eng Ltd
Current assignee: Priden Eng Ltd
Priority date: 2019-03-05
Filing date: 2019-03-05
Publication date: 2020-09-09
Anticipated expiration: 2039-03-05
Also published as: GB201902966D0; GB2581982B

Abstract

A system (20, Fig 2), possibly housed within a vehicle (V), and associated method, for conveying particulate material (22) e.g. animal feed, comprises: a conduit (27), a pump (28) arranged to pump air through conduit (27) to carry particulate material (22) along conduit (27), a rotary feeder 26 to feed particulate material (22) from a store / bin (21) into conduit (27). A venting apparatus to vent air that has passed out of conduit (27) via the rotary feeder 26, comprising manifold 29 arranged between feeder hopper (25) and inlet (26A) of rotary feeder 26. Manifold 29 defines an aperture 31 defining a channel through which particulate material (22) reaches inlet (26A) of feeder 26 from hopper 25. One or more inlets 29B to venting apparatus lie or extend around all sides 29A of the channel to improve venting of air that passed out through rotary feeder 26. Channel 31 provides a pathway for air from inlet 29B to outlet 29C of manifold 29 that communicates with inlet (30A) of vent pipe (30). Guide elements 33A, 33B are also shown.

Description

An Improved System for Conveying Particulate Material The application relates to a conveying system that uses air to carry particulate material along a conduit The conveying system was conceived to be fitted and carried by a lorry used to deliver bulk particulate material such as animal feed, grain or the like; the conveying system being used to blow the particulate material carried loose on the lorry, off the lorry to a silo.

With reference to Figure 1, which illustrates a prior art system, the lorry 1 (shown schematically) comprises a main hopper 2 in which the animal feed (or other particulate material) 3 is stored during transport by the lorry I. When the feed 3 is to be transferred off the lorry 1 a travelling belt, below the main hopper 2, is operated to carry feed 3 from the main hopper 2 to a feeder hopper 5 that sits above a rotary feeder 6. The rotary feeder 6 feeds the animal feed 3 into a hose 7 through which air is forced at high pressure by a pump 8 The feed 3 is carried along the hose 7 by the force of the air to a silo 9.

A problem is that as the vanes of the rotary feeder 6 rotate, air is 'scooped up' from the high pressure hose 7 and carried into the feeder hopper 5. This interrupts the flow of feed 3 from the hopper 5 into the rotary feeder 6, stowing down the rate that feed 3 is fed into the hose 7. Exceptionally, it can lead to the formation of a high pressure air 'bubble' or 'pocket' above the rotary feeder 6 that significantly restricts the passage -2 -of particulate material towards the feeder 6. A solution to this problem is to use a vent in the form of a straight tube 10 that has an inlet 10A arranged about the inlet of the rotary feeder 6 and which extends up above the level of the feed 3 within the feeder hopper 5. The tube 10 provides means for air passing from the hose 7 through the rotary feeder 6 to escape, reducing the likelihood of the formation of pockets.

Related prior art rotary feeding systems are described in US2008/0178953 and US2010237267 in which high pressure air is vented from between spaces between the rotor vanes before they come into communication with the inlet side of the rotary feeder.

According to an aspect of the invention there is provided a system for conveying particulate material, the system comprising: a conduit; a pump arranged to pump air through the conduit to carry the particulate material along the conduit; feeding apparatus comprising a rotary feeder,the feeding apparatus arranged to feed particulate material from a store into the conduit; and venting apparatus having one or more inlets, e.g. arranged about an inlet side of the rotary feeder to vent away air that has passed from the conduit via the rotary feeder to an inlet side of the rotary feeder; the venting apparatus comprising a manifold that provides the one or more inlets, the manifold defining, at least in part, a channel through which particulate material passes to reach the rotary feeder. -3 -

The use of a manifold improves the venting of air from the inlet compared with the system of Fig 1 whilst enabling use of a relatively simple des gn of rotary feeder that does not include its own venting system The improved venting of air allows increased flow rates of particulate material into the feeder. Where applied to the transportation of particulate material delivery on lorries, it reduces the time to off load the particulate material at the destination address The manifold may provide a closed shaped channel. This allows the one or more inlets to be positioned on (or extend about where there is only one inlet) all sides of the channel in order to more effectively draw air out of the channel and thus improve venting. The manifold may be hollow to provide a fluid pathway for air, that extends around a majority of the perimeter of the channel, and favourably substantially the entirely of the perimeter of the channel The manifold favourably has an outlet through which air having entered the manifold through the one or more inlets, is expelled The one or more inlets may open directly into the channel to vent air that has passed through the rotary feeder. The one or more inlets may be arranged about or extend across multiple sides of the channel. The one or more inlets may extend or lie about all sides of the channel allowing air within the channel to flow radially out from the channel in substantially any direction towards the one or more inlets To provide the most effective venting of air, the one or more inlets may extend around a majority of the, favourably substantially the whole, perimeter of the channel. -4 -

The system may comprise means to draw air through the vent. By positively drawing air through the vent rather than relying solely on the high pressure air venting naturally the system provides improved feed flow rate into the rotary feeder which leads to increases rate of transfer of particulate material.

The system may comprise means to draw air through the venting apparatus using the venturi effect. As such, the system may comprise a venturi device, an outlet of the venting apparatus being connected to the venturi device in order to draw air through the vent Favourably the outlet of the venting apparatus is arranged about an inlet to the pump such that air drawn towards the pump inlet by the pump acts to draw air out of the venting apparatus's outlet.

Although less preferred, a positive drawing force may be created through other means such as provision of an additional pump to blow/suck air through the venting apparatus.

The system may include a guide arranged to guide air that has passed through the feeder towards the one or more inlets, or a portion thereof The system may include a guide arranged to guide air to an inlet or portion of an inlet that is positioned on a leading side of the manifold. The leading side being the side where the radially outward edge of rotating vanes of the rotary feeder initially appear, as viewed through the input to the feeder. -5 -

The feeding apparatus may comprise means to convey the particulate material from the store to the inlet of the rotary feeder. This may be implemented using an endless belt with an associated drive system. The store may itself form part of the system.

The particulate material may include one or more of powder, pellet and granular material. The particulate material may comprise one or more of grain, animal feed, agricultural product, wood chips, biomass, saw dust and food stuff According to another aspect of the invention there is provided a vehicle for transporting bulk particulate material, the vehicle comprising a bin for storing the bulk particulate material to be transported, and the system as variously described above for conveying the particulate material from the bin off the vehicle.

The vehicle may comprise a wheeled vehicle such as, for example, a lorry and/or a trailer.

According to a further aspect of the invention there is provided a method for conveying particulate material, the method comprising: using a pump to pump air through a conduit to carry the particulate material along the conduit; using feeding apparatus including a rotary feeder to feed particulate material from a store into the conduit; and using venting apparatus having one or more inlets arranged about an inlet side of the rotary feeder to vent away air that has passed from the conduit via the rotary feeder to an inlet side of the rotary feeder; the venting apparatus comprising a manifold that provides the one or more inlets, the manifold defining, at least in part, a channel through which particulate material passes to reach the rotary feeder. -6 -

The invention will now be described by way of example with reference to the following figures in which: Figure 1 is a schematic of a prior art system for conveying particulate material from a lorry; Figure 2 is a schematic of a system for conveying particulate material from a vehicle, Figure 3 is a perspective view of the rotary feed and manifold of the system of Figure 2, and Figure 4 is a schematic plan view of the manifold looking from the outlet of the feeder hopper towards the rotary feeder.

With reference to Figure 2 there is shown a vehicle V, e.g. lorry or trailer pulled by the lorry, having a bin 21 for holding particulate material 22 to be transported by the vehicle V, and a system 20 for conveying a flowable particulate material from the bin 21.

The system 20, which is carried by the vehicle V, comprises an endless belt 23 positioned at an outlet 21A of the bin 21. The endless belt 23, driven by a conventional driving system 24, carries the particulate material 22 to a feeder hopper 25 that sits about an inlet 26A of a rotary feeder 26. The rotary feeder 26 comprises a vaned rotor 26B that feeds (e.g. meters) particulate material 22 from the feeder hopper 25 into a conduit 27. A pump 28, having an air inlet 28A and an air outlet 28B -7 -that is in fluid communication with conduit 27, is arranged to force air (e.g. at -2 bar) through the conduit 27 to carry the particulate material 22 along the conduit 27, off the vehicle V to a silo or other store.

The conduit 27 is extendable through attachment of a flexible extension piece 27', e.g. a hose, in order to facilitate stowage of the conduit 27 on the vehicle V when not in use.

The system further includes venting apparatus to vent away air that has passed from the conduit 27 through the rotary feeder 26. The venting apparatus comprises a manifold 29 arranged between the feeder hopper 25 and the inlet 26A of the rotary feeder 26. The venting apparatus further includes a vent pipe 30 which may be of any suitable cross-sectional shape.

With reference to Figures 3 & 4, the manifold 29 defines an aperture 31 providing a channel through which particulate material from the feeder hopper 25 falls to reach the inlet 26A of the rotary feeder 26.

Sides 29A of the manifold 29 that face into the channel 31 have openings that provide an inlet 29B for air into the manifold 29 that extends about all sides of the channel 31, and substantially the whole periphery of the channel 3 1. The interior of the manifold 29 is hollow forming a chamber completely surrounding the channel 31 that provides a pathway for air from the inlet 29B to an outlet 29C of the manifold 29 that communicates with an inlet 30A of vent pipe 30. The interior pathway favourably -8 -extends around substantially the whole circumference, i.e. all four sides of the channel 31 Referring back to Fig 2, the vent pipe 30 has an outlet 30B positioned proximate the air inlet 28A of pump 28 such as to cause air to be positively drawn from the vicinity of the inlet 26A of the rotary feeder 26, via inlet 29B of manifold though pipe 30 and out of pipe outlet 30B.

To provide a reliable drawing force through vent pipe 30, the outlet 30B of the pipe 30 communicates with the inlet 28A of the pump 28 via a venturi device 31. The venturi device 32 comprises a conduit 31A through which air is drawn from an inlet of the device 32 towards the pump inlet 28A. The conduit 32A has a constriction 32B The outlet 30B of the vent pipe 30B is opens into the conduit 31 at the constriction 32B. The reduction in air pressure that results from air flowing through the constriction acts to draw air from the vent pipe 30 into conduit 32A towards pump inlet 28A.

The system further comprises a guide 33 comprised from a pair of guide elements 33A 33B arranged to guide air carried from the conduit 27 by the vaned rotor 26B towards manifold inlet 29A. A first guide element 33A is arranged on an inlet wall 26C of the feeder 26 in order to be as close to the radial edge of the vanes of the vaned rotor 26A as possible. The other element 33B is arranged directly above the first element 33A, on the manifold 29. Both guide elements 33A 33B are arranged on a leading side L of the feeder 26, being the side, as viewed through the channel 31, -9 -that the vanes first appear as they rotate As the vanes are angled with respect to the leading side of the inlet (as seen in Fig 4) , each vane will appear from one end of the leading side (herein referred to as the leading end LE) before the other end of the leading side As the rotor 26B rotates there are periodic rapid expulsions of air in the region of the leading end LE as the space behind each vane that holds high pressure air from the conduit 27 communicates with the feeder inlet 25B The guide 33 is therefore positioned above this region in order to guide the expulsions of air towards the inlet 29B, minimising the affect the expulsions have on the flow of particulate material towards the feeder 26.

Variations on the above described example are possible, for example, rather than a plurality of inlets spaced around the aperture, the manifold may comprise a single substantially continuous inlet. The greater the extent the openings extend around the perimeter of the channel the better as it allows more effective venting of air from all regions of the channel. However, it would be possible to provide one or more inlets that extend about only a relatively small portion of the aperture's perimeter, e.g across only one side or only at the corners of the aperture.

In the embodiment the aperture 31 has a rectangular shape but could be of other shapes such as, for example, circular. Although less preferred the channel provided by the aperture 31 may not have a closed perimeter.

-10 -The feed hopper 5, although preferred, is optional. The system may use a conveyer of a form other than a continuous belt, e.g. an auger. Alternatively the system may omit the conveyer such that particulate material is fed directly from the bin to the feed hopper 5 or rotary feeder 6 if the feed hopper 5 is omitted.

Rather than, or in addition to arranging the outlet of the vent pipe adjacent the inlet to the pump, other means may be used to draw air through the vent. For example, the system may comprise an aspirator arranged to suck/blow air from the inlet of the feeder through the vent Although less preferred, the system need not include means to positively drawn air through the vent The guide may comprise a single element only or more than two elements. The guide elements may be omitted entirely.

It will be appreciated that the system described above may be used to convey particulate material in applications other than from a vehicle For example the system may be used to transport particulate material from one area of a factory to another.

The conduit need not comprise an extension piece. The conduit may be provided by rigid or flexible tubing or a combination thereof The vent may include a filter to filter the air passing through it before it is drawn into the pump.

The venting apparatus may be incorporated with the feeder rather than arranged above it.

Claims

-12 -Claims A system for conveying particulate material, the system comprising: a conduit; a pump arranged to pump air through the conduit to carry the particulate material along the conduit; feeding apparatus comprising a rotary feeder, the feeding apparatus arranged to feed particulate material from a store into the conduit, and venting apparatus having one or more inlets arranged about an inlet side of the rotary feeder to vent away air that has passed from the conduit via the rotary feeder to an inlet side of the rotary feeder; the venting apparatus comprising a manifold that provides the one or more inlets, the manifold defining, at least in part, a channel through which particulate material passes to reach the rotary feeder.
A system according to claim 1 wherein the one or more inlets of the manifold open directly into the channel.
A system according to claim 1 or 2 wherein the one or more inlets are arranged about multiple sides of the channel.
A system according to claim 2 or 3 wherein the one or more inlets extend substantially about the whole periphery of the channel.
5. A system according to any previous claim wherein the manifold is hollow to define a pathway for air between the one or more inlets and an outlet of the manifold, the pathway extending around the channel.
6. A system according to any previous claim comprising a guide arranged to guide air that has passed through the feeder to the feeder inlet towards the one or more inlets, or a portion of an inlet of the manifold.
7. A system according to claim 6 wherein the guide is arranged on a leading side of the manifold to guide air that is expelled from the rotary feeder from the leading side.
8. A system according to any previous claim wherein the feeding apparatus comprises means to convey the particulate material from the store to the inlet of the rotary feeder.
A system according to claim 8 wherein the means to convey the particulate material from the store to the inlet of the rotary feeder, comprises an endless belt.
10. A system according to any previous claim wherein the feeding apparatus comprises a feeder store that holds particulate material conveyed from the store to be fed to the rotary feeder.
1L A system according to claim 10 wherein the manifold is arranged between the feeder store and the rotary feeder.
-14 - 12. A system according to any previous claim wherein the inlet of the venting apparatus is arranged on an inlet side of the rotary feeder to vent air that has passed from the conduit via the rotary feeder to the inlet of the rotary feeder.
13. A system according to any previous claim comprising means to draw air through the one or more inlets into the venting apparatus.
14. A vehicle for transporting bulk particulate material, the vehicle comprising a bin for storing the bulk particulate material to be transported, and the system of any claim 1-13 for conveying the particulate material from the bin off the vehicle.
15. A system for conveying particulate material, the system comprising: a conduit; a pump arranged to pump air through the conduit to carry the particulate material along the conduit; feeding apparatus comprising a rotary feeder, the feeding apparatus arranged to feed particulate material from a store into the conduit; and a venting apparatus having one or more inlets arranged to vent away air that has passed from the conduit into the rotary feeder away, the vent comprising a manifold that provide the one or more inlets, the manifold defining a channel through which particulate material passes; the manifold having a chamber that extends around a majority of the perimeter of the channel, the one or more inlets opening into the chamber.-15 -
16. A method for conveying particulate material, the method comprising: using a pump to pump air through a conduit to carry the particulate material along the conduit, using feeding apparatus including a rotary feeder to feed particulate material from a store into the conduit; and using venting apparatus having one or more inlets arranged about an inlet side of the rotary feeder to vent away air that has passed from the conduit via the rotary feeder to an inlet side of the rotary feeder-the venting apparatus comprising a manifold that provides the one or more inlets, the manifold defining, at least in part, a channel through which particulate material passes to reach the rotary feeder.