GB2067628A

GB2067628A - Dust suppression in coal mines

Info

Publication number: GB2067628A
Application number: GB8035776A
Authority: GB
Original assignee: Boldry B E; Whinfrey A F
Current assignee: Boldry B E; Whinfrey A F
Priority date: 1979-11-09
Filing date: 1980-11-07
Publication date: 1981-07-30
Also published as: GB2067628B

Abstract

Dust suppression apparatus including wire mesh panels designed to filter the air in a coal mine. In order to trap the dust at source, the wire mesh panels (14, 16) are positioned on at least two sides of a coal cutting machine and there is an arrangement whereby water is caused to pass down the wire mesh panels (14, 16) as the machine operates so that dust is washed down into a collection trough (22). <IMAGE>

Description

SPECIFICATION Dust suppression in coal mines The invention relates to dust suppression in coal mines and has for its object to provide an improvement therein.

It has been previously been proposed to suppress the dust produced in coal mines by the use of various water spray apparatus and by the use of wire mesh screens designed to filter the air circulated throughout the mine. However, such previously employed means have been only partially successful and the problem of dust in coal mines is still serious, largely because the winning of coal by power driven machinery produces great quantities of dust.

According to the invention, there is provided a coal cutting machine provided on at least two sides with a mesh screen down which water is caused to flow to a collecting trough, the arrangement being such that as coal is cut from the seam in which the machine is operating, the dust which is also produced is trapped on the mesh screen and washed down into the collection trough by the flow of water. The mesh screen will preferably be made of wire mesh and will preferably be provided along an upper edge with a flexible element arranged to contact the roof of the seam along which the machine is traversed to prevent the escape of dust laden air. The flexible element may be in the nature of a brush the flexible bristles of which touch the roof of the seam.A pump will preferably be provided to circulate the water, that is to say to raise the water from the collecting trough to a distributing device extending along the upper edge of the screen. Screen panels at the opposite ends of the coal cutting machine may be detachably mounted so that one or the other can be removed before the machine is set in motion, depending upon the direction in which the machine is to be traversed along the coal face (and in this case a single screen panel can be used for fitment at the opposite ends of the machine alternately). On the other hand, means may be provided whereby the screen panels at the opposite ends of the machine can be retracted in turn so that the machine can be traversed in one direction and then in the other direction.In addition to the water passing down the screen panels, there may be at least one water curtain falling on the outer side of the frame parallel to the screen panels, from a deflector plate positioned above the screen panels, said water curtain acting as a second filter should any dust particles escape through the screen panels.

In order that the invention may be fully understood and readily carried into effect, the same will now be described, by way of example only, with reference to the accompanying drawings, of which: Fig. 1 is a diagrammatic plan view of a coal cutting machine in operation in a coal seam, Fig. 2 is a perspective view of a wire mesh screen arrangement which surrounds the machine, and Fig. 3 is a diagrammatic view which will presently be referred to.

Referring now to Fig. 1 of the drawings, the coal cutting machine 10 there illustrated is shown to be in operation and being traversed in the direction of the arrow along a coal seam. A wire mesh screen generally indicated 12 is shown to have been mounted on the machine to move with it and to trap the dust which is produced as the machine is operating.

In Fig. 2, the screen 12 is shown to be constituted by two wire mesh panels 14 and 1 6, the panel 14 extending along the side of the machine remote from the coal face and the panel 1 6 being mounted at the trailing end of the machine (that is to say, since for example in Fig. 1 the machine is shown to be moving to the right the screen panel 1 6 is mounted at the left hand end of the machine as viewed in that drawing).

Means (not shown) are provided whereby the screen panel 1 6 can quickly be detached from the position in which it is shown in the drawings and mounted at the opposite end of the machine so that the latter can be moved further into the coal face and then traversed in the opposite direction.

As shown in Fig. 3 the wire mesh screens are provided at their upper ends with water spray nozzles 1 8 which discharge water against deflector plates 20. This allows water to run evenly down the wire mesh screens. Further water spray nozzles are provided to spray water onto other deflector plates which spreads the water and forms a curtain as it falls freely into the collecting troughs. The panels extend downwards into shallow collecting troughs 22 into which the water trickling from the deflector plates also falls.

Filtered water can be pumped from the collecting troughs back up to the nozzles 18 by a pump (not shown). Flexible elements 24 each in the nature of a brush extend along the upper edges of the wire mesh screens and are arranged to contact the roof of the coal seam along which the machine is being traversed. In this way, despite the uneven character of the roof, the dust is very largely prevented from escaping from the confined space surrounding the machine. In Fig. 3, which is a diagrammatic sectional view, it can be seen that separate water curtains extend downwards from the deflector plates 20, spaced from the watered screen.

The arrangement is such that a very large proportion of the dust which is produced as the machine is traversed along the coal face is trapped on the mesh screen or in the water curtains and washed down into the collecting trough by the flow of water The filtering of the water in the collecting trough produces a slurry which can be removed from time to time and disposed of by the conveyor on which the coal is carried away.

Various modifications may be made. For example, instead of the screen panel 1 6 being capable of being mounted in turn at the opposite ends of the machine there could be separate screen panels at each end of the machine, means being provided for moving the panels, alternately, to inoperative positions depending on the direction in which the machine is to be transversed along the coal face.

It will be understood that although in the drawings, the wire mesh screens are shown to be of a slab sided form, they need not necessarily be of this form and could be shaped to conform more closely to the outline configuration of the coal cutting machine. In other words the mesh panels may be either stepped or curved in either vertical or horizontal planes, or in both planes so far as this can be effected whilst enabling the water to flow freely down the screens.

It is thought that the suppression of coal dust in the manner described above will be especially effective because the dust is being trapped at source rather than after it has become entirely airborne and dispersed throughout the mine.

Claims

1. A coal cutting machine provided on at least two sides with a mesh screen down which water is caused to flow to a collecting trough, the arrangement being such that as coal is cut from the seam in which the machine is operating, the dust which is also produced is trapped on the mesh screen and washed down into the collection trough by the flow of water.

2. A coal cutting machine according to claim 1, in which the mesh screen is made of wire mesh and is provided along an upper edge with a flexible element, arranged to contact the roof of the seam along which the machine is traversed, to prevent the escape of dust laden air.

3. A coal cutting machine according to claim 2, in which the flexible element is in the nature of a brush, the flexible bristles of which touch the roof of the seam.

4. A coal cutting machine according to any one of the preceding claims, in which a pump is provided to circulate the water, that is to say to raise the water from the collecting trough to a distributing device extending along the upper edge of the screen.

5. A coal cutting machine according to any one of the preceding claims, in which screen panels at the opposite ends of the coal cutting machine is detachably mounted so that one or the other can be removed before the machine is set in motion,' depending upon the direction in which the machine is to be traversed along the coal face (and in this case a single screen panel can be used for fitment at the opposite ends of the machine alternately).

6. A coal cutting machine according to any one of claims 1 to 4, in which means are provided whereby the screen panels at the opposite ends of the machine can be retracted in turn so that the machine can be traversed in one direction and then in the other direction.

7. A coal cutting machine according to any one of the preceding claims, in which in addition to the water passing down the screen panels, there is at least one water curtain falling on the outer side of the frame parallel to the screen panels, from a deflector piate positioned above the screen panels, said water curtain acting as a second filter should any dust particles escape through the screen panels.

8. A coal cutting machine provided with a mesh screen constructed, arranged and adapted to operate substantially as hereinbefore described with reference to and as illustrated by the accompanying drawings.