GB2088483A

GB2088483A - Waste liquid collection apparatus

Info

Publication number: GB2088483A
Application number: GB8033107A
Authority: GB
Original assignee: Drum Engineering Co Ltd
Current assignee: Gardner Denver UK Ltd
Priority date: 1980-10-14
Filing date: 1980-10-14
Publication date: 1982-06-09

Abstract

An apparatus for the collection of waste liquid materials comprises an exhauster adapted to draw waste liquid materials into a closed reservoir 12. In order to prevent waste liquid materials in the reservoir 12 from entering the exhauster, the exhauster draws air from the reservoir 12 via a centrifugal impeller 40 which, whilst allowing air to enter, throws away centrifugally any liquid which comes into contact therewith should the liquid level in the reservoir become too high. The increased power requirement to drive the impeller 40 which occurs when the impeller contacts liquid in the reservoir can be used to close a valve in the exhauster inlet line to assist in preventing liquid entering the exhauster. <IMAGE>

Description

SPECIFICATION Waste liquid collection apparatus The present invention relates to apparatus for the collection of waste liquid materials and is particularly concerned with a device for preventing waste liquids from entering the exhauster used to draw such waste liquids into a collection reservoir.

Waste liquids are collected by drawing them into a reservoir, for example, a road tanker, by means of a vacuum pump, referred to hereinafter as an exhauster. A problem with this type of arrangement is that, almost inevitably, the driver of the vehicle overfills the tank and quantities of liquid are consequently drawn into the exhauster, causing considerable damage thereto.

It is an object of the present invention to provide a means by which liquids are prevented from being drawn into the exhauster.

In accordance with the present invention, the exhauster evacuates the reservoir through a centrifugal impeller whereby liquid in the reservoir contacting the impeller is centrifugally thrown away and thereby prevented from entering the exhauster.

Advantageously, the increased power requirement to drive the impeller which occurs when the impeller contacts such liquid is used to close a valve device in the exhauster inlet line whereby to assist in preventing liquid entering the exhauster.

Preferably, the impeller comprises a plurality of generally radially directed pipes coupled to the exhauster inlet, the outer surfaces of the pipes defining impeller blades for radially displacing liquid coming into contact therewith. Preferably the impeller can generate more than 1 Bar pressure.

The invention is described further hereinafter, by way of example, with reference to the accompanying drawing which is a diagrammatic vertical section through e one embodiment of a device in accordance with the present invention.

The illustrated device has a body 10 which is adapted to be mounted to the top of a tank 12 by means of a flange 14 and bolts 16. The tank has an inlet (not shown) by which waste liquids, or liquid based mixtures such as slurries, can be drawn via inlet pipework into the tank by means of a partial vacuum created in the tank 12. The vacuum is generated by means of an exhauster (not shown) which is coupled to the interior of the tank 12 by way of the body 10.

The body 10 is connected to the exhauster inlet by way of a flanged coupling 17 which communicates with an internal chamber 18 of the body 10. Journal led for rotation in the chamber 18 is a hollow shaft 20 mounted in bearings 22, 24 supported in the body 10. The shaft 20 has a plurality of slots 26 allowing communication between the chamber 18 and the interior 28 of the shaft 20. The upper end of the shaft 20, as viewed in the drawing, is closed and is con nected via a coupling 30 to a further shaft 32 driven by a motor 34 rigidly mounted to the top of the body 10. The motor can be of any convenient form, e.g.

electric hydraulic, pneumatic, capable of rotating the hollow shaft 20 at the desired speed. Rotary seals 36 on each side of the bearings 22,24 prevent the vacuum from being lost around the latter bearings.

Attached to the lower end of the cylindrical shaft 20 is a frustro-conical extension tube 38, the lower end of which carries an impeller device indicated generally at 40. The tube 38 extends into the top of the tank 12 by way of an aperture 39 in a manner enabling the tube 38 to rotate relative the tank without losing the vacuum therein. The impeller device 40 is attached to the tube 38 by means of an axially directed screw-threaded bolt 42 engaged in a correspondingly screw-threaded axial bore 44 in a radial spider 46. The device 40 defines a plurality of curved radially extending passages (four in this example) 46 which all communicate directly with the tube 38 and hence with the shaft interior 28 and chamber 18.The exterior surfaces of the passages 46 define centrifugal impeller blades adapted to displace in a generally radially outward direction any liquids which might come into contact therewith.

In use, the exhauster is coupled to the tank 12 via the device of the present invention, and evacuates the tank by way of the centrifugal impeller 40. When the level of liquid drawn into the tank rises in the tank to come into contact with the impeller there is a considerable increase in the power requirement to drive the impeller, whilst at the same time liquid is thrown away by the rotary movement of the impeller and thus prevented from being drawn up the tube 38 and into the exhauster. This increased power requirement can be detected, for example in the coupling 30 or in the power supplyto the motor 34, and used as a signal to close a valve (not shown) in a line connecting the exhausterto the body 10.

Liquid is thus prevented from being drawn into the exhauster even if the liquid level in the tank is above the level of the impeller and the exhauster is thereby protected against damage.

1. Apparatus for the collection of waste liquid materials comprising an exhauster adapted to draw waste liquid materials into a reservoir, wherein the exhauster is arranged to evacuate the reservoir through a centrifugal impeller constructed such that when liquid in the reservoir contacts the impeller such liquid is centrifugally thrown away from the impeller and is thereby prevented from entering the exhauster.

2. Apparatus as claimed in claim 1, wherein the increased power requirement to drive the impeller which occurs when the impeller contacts liquid in the reservoir is used to close a valve device located upstream of the exhauster inlet whereby to assist in preventing liquid entering the exhauster.

3. Apparatus as claimed in claim 1 or 2, wherein the impeller comprises a plurality of generally radially directed pipes coupled to the exhauster inlet, the outer surfaces of the pipes defining impeller blades for radially displacing liquid coming into con The drawing(s) originally filed was/were informal and the print here reproduced is taken from a later filed formal copy.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Waste liquid collection apparatus The present invention relates to apparatus for the collection of waste liquid materials and is particularly concerned with a device for preventing waste liquids from entering the exhauster used to draw such waste liquids into a collection reservoir. Waste liquids are collected by drawing them into a reservoir, for example, a road tanker, by means of a vacuum pump, referred to hereinafter as an exhauster. A problem with this type of arrangement is that, almost inevitably, the driver of the vehicle overfills the tank and quantities of liquid are consequently drawn into the exhauster, causing considerable damage thereto. It is an object of the present invention to provide a means by which liquids are prevented from being drawn into the exhauster. In accordance with the present invention, the exhauster evacuates the reservoir through a centrifugal impeller whereby liquid in the reservoir contacting the impeller is centrifugally thrown away and thereby prevented from entering the exhauster. Advantageously, the increased power requirement to drive the impeller which occurs when the impeller contacts such liquid is used to close a valve device in the exhauster inlet line whereby to assist in preventing liquid entering the exhauster. Preferably, the impeller comprises a plurality of generally radially directed pipes coupled to the exhauster inlet, the outer surfaces of the pipes defining impeller blades for radially displacing liquid coming into contact therewith. Preferably the impeller can generate more than 1 Bar pressure. The invention is described further hereinafter, by way of example, with reference to the accompanying drawing which is a diagrammatic vertical section through e one embodiment of a device in accordance with the present invention. The illustrated device has a body 10 which is adapted to be mounted to the top of a tank 12 by means of a flange 14 and bolts 16. The tank has an inlet (not shown) by which waste liquids, or liquid based mixtures such as slurries, can be drawn via inlet pipework into the tank by means of a partial vacuum created in the tank 12. The vacuum is generated by means of an exhauster (not shown) which is coupled to the interior of the tank 12 by way of the body 10. The body 10 is connected to the exhauster inlet by way of a flanged coupling 17 which communicates with an internal chamber 18 of the body 10. Journal led for rotation in the chamber 18 is a hollow shaft 20 mounted in bearings 22, 24 supported in the body 10. The shaft 20 has a plurality of slots 26 allowing communication between the chamber 18 and the interior 28 of the shaft 20. The upper end of the shaft 20, as viewed in the drawing, is closed and is con nected via a coupling 30 to a further shaft 32 driven by a motor 34 rigidly mounted to the top of the body 10. The motor can be of any convenient form, e.g. electric hydraulic, pneumatic, capable of rotating the hollow shaft 20 at the desired speed. Rotary seals 36 on each side of the bearings 22,24 prevent the vacuum from being lost around the latter bearings. Attached to the lower end of the cylindrical shaft 20 is a frustro-conical extension tube 38, the lower end of which carries an impeller device indicated generally at 40. The tube 38 extends into the top of the tank 12 by way of an aperture 39 in a manner enabling the tube 38 to rotate relative the tank without losing the vacuum therein. The impeller device 40 is attached to the tube 38 by means of an axially directed screw-threaded bolt 42 engaged in a correspondingly screw-threaded axial bore 44 in a radial spider 46. The device 40 defines a plurality of curved radially extending passages (four in this example) 46 which all communicate directly with the tube 38 and hence with the shaft interior 28 and chamber 18.The exterior surfaces of the passages 46 define centrifugal impeller blades adapted to displace in a generally radially outward direction any liquids which might come into contact therewith. In use, the exhauster is coupled to the tank 12 via the device of the present invention, and evacuates the tank by way of the centrifugal impeller 40. When the level of liquid drawn into the tank rises in the tank to come into contact with the impeller there is a considerable increase in the power requirement to drive the impeller, whilst at the same time liquid is thrown away by the rotary movement of the impeller and thus prevented from being drawn up the tube 38 and into the exhauster. This increased power requirement can be detected, for example in the coupling 30 or in the power supplyto the motor 34, and used as a signal to close a valve (not shown) in a line connecting the exhausterto the body 10. Liquid is thus prevented from being drawn into the exhauster even if the liquid level in the tank is above the level of the impeller and the exhauster is thereby protected against damage. CLAIMS

3. Apparatus as claimed in claim 1 or 2, wherein the impeller comprises a plurality of generally radially directed pipes coupled to the exhauster inlet, the outer surfaces of the pipes defining impeller blades for radially displacing liquid coming into con The drawing(s) originally filed was/were informal and the print here reproduced is taken from a later filed formal copy. tact therewith.

4. Apparatus as claimed in claim 3, comprising a body which is mounted on top of the reservoir, and has an internal chamber coupled to the exhauster inlet, a hollow shaft which lies partly within said internal chamber of the body so as to communicate therewith and which extends out of said body by way of an air-tight rotary joint, the end of said shaft remote from said body carrying said impeller blades, and drive means for rotating said hollow shaft and the impeller coupled thereto.

5. A device for use in apparatus for the collection of waste liquid materials of the type wherein an exhauster draws waste liquid materials into a reservoir, the device comprising a hollow shaft which is adapted to be journalled in an air-tight manner in the roof of the reservoir so as to project downwardly into the interior of the reservoir, means enabling the hollow interior of the shaft to be coupled to the exhauster inlet, a centrifugal impeller attached to the end of said hollow shaft which is to project into the reservoir, and means for rotating the hollow shaft and the impeller carried thereby so that, in use, when liquid in the reservoir contacts the impeller such liquid is centrifugally thrown away from the impeller and is thereby prevented from entering the exhauster.

6. Apparatus for the collection of waste liquid materials substantially as hereinbefore described with reference to the accompanying drawing.