IE83765B1 - Solids/liquids separator - Google Patents

Description

SOLIDS/LIQUIDS SEPARATOR present invention relates to for The separators separating solids from liquid, e.g. grit from water and an associated method of separating solids from liquids.

Solids/liquids separators are frequently used in waste water treatment plants so as to remove e.g. grit from the flow settlement in the treatment process. waste water and prevent and wear to equipment Grit separators are also used in other industries such as mining.

Traditional equipment is available to separate and these grit involve rotating and reciprocating stepping mechanism, which gradually lift out the grit. screens (augers) This equipment is large and heavy to allow for The materials used are heavy duty in order to ensure long life the wear that grit can cause within the equipment. because the moving parts are difficult to access.

The present invention seeks to provide an improved solids/liquids separator.

According to a first aspect of the present invention there is provided a solids/liquids separator comprising a tank with an inlet for mixed solids/liquids, a weir at a first level, a solids outlet at a second level above the first level and transfer means arranged to transfer solids to the solids outlet from a third level below the first level, wherein the tank includes a plate member extending between the second level and the third level.

The separator thus provides solids that are separated from the liquids without the need of complex and heavy duty equipment. The solids/liquids enter the tank through the inlet and gravity causes the solids to fall to the base of the tank. The transfer means then transfers solids which have fallen from the suspension to the solids outlet which is located at a higher level. Below the solids outlet the tank is provided with a weir where the liquid which is free from entrained solids exits the separator.

A preferred embodiment of the present invention has the weir comprising the wall of the tank.

Preferably the solids outlet may comprise a chute formed between an exterior wall of the tank which may be directly connected to a skip or other waste collector.

The tank advantageously comprises a plate member which is shaped to encourage the solids to fall out of the suspension.

The transfer means advantageously includes a wear part tank resilient biasing of the wear part against the tank allows which is resiliently biased against part of the according to a preferred embodiment of the invention. the pressure to be adjusted and also compensates for wear when in use.

The wear part is often formed from a polymeric material which may be self lubricating and also can be designed to have the desired wear characteristics.

Preferred plastics are polypropylene, polyethylene, polyurethane and polystyrene and it is presently preferred to use polypropylene.

It is preferred that the wear part is releasably mounted on the transfer means so as to allow simple replacement of the wear part in situ.

The transfer means normally works through a part rotation sweep to remove solids between the third level and the solids outlet. This motion is easy to control without complex drive arrangements.

It is preferred if the transfer means uses a brush means as the wear part. The brush allows filtering of liquids back from the solids and so minimizes the liquid loss.

According to a second aspect of the present invention there is provided a method of separating solid from liquids comprising the steps of: (a) inputting solids/liquids mixture into a tank; (b) allowing the solids to settle in the tank; (C) providing a weir at a first level arranged to allow the liquid free from the solid to flow thereover; (d) transferring solids to a solid output at a second level above the first level from a third level below the first level along a plate member extending between the second level and the third level by transferring means.

The method of the present invention may be conducted on a solids/liquids separator according to the first aspect of the invention.

A preferred embodiment of the present invention will now be described with reference to the accompanying drawings, in which: Fig. 1 shows a side cross sectional view of a separator according to the present invention; Fig. 2 shows a plan view of the separator of Figure 1; Fig. 3a shows a section view along A—A of Figure 1; Fig. 3b shows a section view along B—B of Figure 1; Fig. 4 shows an enlarged view of the transfer means of Figure l; Fig. 5 shows a side transfer means of Figure 4; Fig. 6 shows a bottom plan view of the transfer means of Figure 4; Fig. 7 shows an enlarged view of area A shown in Figure 5; and Fig. 8 shows an illustration of the brush holder of Figure 4. shows a embodiment of the Figure 1 preferred a transfer means 20 and a solids/liquids separator of the present invention. separator comprises a tank 10, control unit 30.

The tank 10 has a base plate 12 fixed therein. The base plate 12 is shaped to maximise the efficiency of the present invention. Inlet 14 is provided for solids/liquids to enter into the tank. Tank 10 inner side walls 16 and base plate 12. These side walls 16 extend above the inlet 14 to a first level. The top edge of the side wall 16 sets the first level forming the weir over which separated liquid flows. The tank 10 has exterior side walls 18 forming the catchment trough for separated liquid.

Transfer means 20 is resiliently biased to base plate 12 as explained in more detail hereinafter. The transfer means 20 is arranged to sweep a portion of the base plate (third level) up the base plate to a level above the weir (second level). tank through inlet 14 entrained in the solids/liquid mixture fall through gravity (third level) is such that the transfer means 20 will transfer the from a level below the level of the weir When water enters the solids onto the base plate 12. The lower level set solids which have dropped out of the suspension along the The solids pushed over the upper level fall into a chute formed base plate 12 up to the upper level (second level). between an interior wall of the tank 19 and an exterior end wall of the tank. This forms the solids outlet.

In the drawings the transfer means 20 comprises a reciprocating arm 22. This is driven by a motor and gear box arrangement 24. A brush means 36 is provided which is The brush means 36 is in Contact with the base plate 12. moved in a partial arc along the base plate 12. transfer means 20 is shown best in Figures 4 through 9.

The brush means 36 is mounted on a first arm segment which is connected to a second arm segment 28. The connection between the first and second arm sections 26, 28 is via a spring loaded connector 38 which includes a pivot The for any with spring adjustment means shown best in Figure 5. spring adjustment means can be used to compensate wear which occurs to the brush means 36 and also to set the initial pressure that the brush means 36 presses against the base plate. The brush means 36 is connected to the arm 26 by means of a fixing arrangement 38.

In the‘ comprises an elongated block 42 in which there are several illustrated embodiment the brush means 36 openings. In each opening a brush cartridge 44 is located.

Each brush cartridge 44 comprises 32 strands of bristle all within a stainless steel tube 44A which is crimped to hold the bristles. back stop 46.

The cartridge 44 is held against moving by Several cartridges 44 extend from the block 42. The block 42 is very simply to replace in situ.

The bristles shown are made by polypropylene and this material wears slowly. The separate brush cartridges 44 are preferred as this provides a natural grid through which the liquid can flow thus minimizing the liquid which is passed to waste with the solids. This is particularly important in waste water applications whereby total liquid recovery is often desired.

As will be clear from Figures 4 through 6 the brush means 36 is supported on the frame assembly 26. The illustrated embodiment provides a simple and efficient manner in which the partial rotating movement of the brush can be provided very reliably. A single motor gear box The control of the brush is provided through the control panel arrangement 20 is used to provide the necessary drive. (not shown). The control panel may be an integral unit or could form a separate unit.

In the illustrated embodiment the drive is configured to drive the brush means 36 to sweep the plate means at.6 but of course this will be It is preferred if there are period where the brush means 36 rpm (revolution per minute), variable depending upon the particular installation. remains stationary.

In the illustrated embodiments, particularly preferred the implemented in a number of ways as will be appreciated by features are shown. However, invention can be the skilled person. Particularly, different drives could be used. A different shape of base plate can be utilised.

Twin weirs as shown can be substituted for a more or less liquid removal means. The brush means could be adapted as required for a particular installations and for example The skilled different plastics may’ be used for the bristles. modifications will readily be apparent to the person.

The preferred grit separator consists of a semi—rotary brush screen mechanism traversing a shaped sheet of metal within the unit. Flow of medium enters the back of the separator and exits over two weir plates either side of the shaped sheet of metal. A "well" created by the weir and shaped sheet of metal allows grit to settle out.

Periodically, e.g. 6rpm, the brush will sweep out the grip into a hopper at the exit end of the separator. To the brush arm will come to rest just before the brush reaches ensure that the grit is as much drained as possible, the top of the shaped metal plate thereby allowing water to drain back into the flow.

The shaped metal plate is bolted into the frame and the brush arm is sprung loaded onto the plate so that when wear takes place on the brush, the brush and the shaped metal plate are always in contact. the bristles are pushing the grit up the plate rather than a Other plastic material can be used and are being developed which Less‘ wear takes place because polypropylene metal to metal faces in traditional grit separators. can perform even better than polypropylene. installed directly into a waste water flow or as part of a separators of the invention can be either degritting process where grit within some of the waste water is pumped up to an elevated degritting station to allow the grit to be deposited into a skip.

Claims (18)

CLAIMS:

1. A solids/liquids separator comprising a tank with an inlet for mixed solids/liquids, a weir at a first level, a solids outlet at a second level above the first level and transfer means arranged to transfer solids to the solids outlet from a third level below the first level wherein the tank includes a plate member extending between the second level and the third level.

2. The solids/liquids separator according to claim 1, wherein the weir comprises a wall of the tank.

3. The solids/liquids separator according to claim 1 or claim 2, wherein the solids outlet comprise a chute formed on an exterior wall of the tank.

4. The solids/liquids separator according to any one of the preceding claims, wherein the plate member is curved.

5. The solids/liquids separator according to any of the preceding claims, wherein a wear part of the transfer means is resiliently biased against part of the tank.

6. The solids/liquid separator according to claim 5, wherein the wear part is formed from a polymeric material.

7. The solids/liquid separator according to claim 6, wherein the polymeric material is selected from the group consisting of: polypropylene; polyethylene; polyurethane; polystyrene.

8. The solids/liquid separator according to any one of claims 5 to 7, wherein the wear part is releasably mounted on the transfer means.

9. The solids/liquid separator according to any one of the the comprises a movable member movable to push the solids preceding claims, wherein transfer means between the third level and the solids outlet.

10. The solids/liquids separator according to claim 9, wherein the transfer means includes drives means arranged to move the movable member.

11. The solids/liquids separator according to claim 10, wherein the movable member is movable along a curve.

12. The solids/liquids separator according to any of the preceding claims, wherein the transfer means comprises a brush.

13. The solids/liquids separator according to all of claims 5 to 12, wherein the movable member comprises the wear part which comprises the brush.

14. The solids/liquids separator according to both of claims 5 and claims dependent thereupon, wherein the wear part is in contact with the plate member.

l5. A method of comprising the steps of: separating solid from liquids (a) inputting solids/liquids mixture into a tank; (b) allowing the solids to settle in the tank; (C) providing a weir at a first level arranged to allow the liquid free from the solid to flow thereover; (d) transferring solids to a solid output at a second level above the first level from a third level below the member extending between the second level and the third first level along a plate level by transferring means.

16. The method of claim 15 conducted in a solids/liquids separator according to any one of claims 1 to 14.

17. A solids/liquids separator as hereinbefore described with reference to, and/or as illustrated by the accompanying drawings.

18. A method of separating solids from liquids as hereinbefore described with reference to, and/or as illustrated by the accompanying drawings. MACUMEEAN &]H)fliDSON, Applicants‘ Agents,