CA2095292A1

CA2095292A1 - Sludge de-watering press

Info

Publication number: CA2095292A1
Application number: CA002095292A
Authority: CA
Inventors: Herbert G. J. Langner
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-04-30
Filing date: 1993-04-30
Publication date: 1994-10-31

Abstract

An improved strainer member and housing therefor, which strainer member and housing are for use in a sludge de-watering press, are disclosed. The housing defines a longitudinal chamber that houses a generally cylindrical strainer member. The inner wall of the strainer member defines an internal passageway. An auger means is rotatably mounted within the internal passageway to advance sludge along the passageway from an inlet port to an outlet port. The strainer member is adapted to retain the relatively solid portion of the sludge within the passageway and to allow passage of the fluid portion of the sludge therethrough into the chamber. The improvement comprises the housing being divided into a plurality of releasably connected modules along its length, and further comprises the strainer member being divided transversely to its axis in to a corresponding plurality of operatively abutting segments. Each of the housing modules can be removed individually so as to inspect or also individually remove the corresponding strainer member segment.

Description

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FIBLD OF THE INVENTION
The present invention relates to devices for de-watering solids or semi-solids and more particularly to sludge de-watering presses. Specifically, the s~rainer members used in such devices are considered.
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!i BAC~ROUND OF TEE INV~TIO~ -Sludge de-watering presses are used in a variety of applications including food processing, waste processing, mineral 10 processing, pulp and paper processing, and the like. In a sludge processing operation, the primary sludge is typically first screened to remove the larger constituents, and then is pre-thickened to reduce the sludge volume. The pre-thickened sludge may also be passed through an after-thickening process. In any ~15 event, the thickened sludge is then de-watered by a suitable de-4 watering press, which basically separates solids and semi-solids from the liquid of the sludge. It has been found that the sludge volume may be reduced by over 90% by such removal of water.

The sludge is entered into an inlet port of the sludge ;~ de-watering press and is collected in a generally cylindrically shaped internal passageway. An advancing mechanism such as an : auger, is operatively mounted within the internal passageway, which passageway is defined by an internal wall in the form of 25 a generally cylindrical strainer member disposed around the . perimeter of the passageway. The auger advances the sludge along !~ the passageway, which causes the sludge to be compressed due to the force of the auger/ the frictional resistance of the internal ':f,`, ~.
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9 ~ ~ 9 2 wall, and the optional narrowing of the internal wall from its inlet end to its outlet end. As the sludge is compressed by the auger, the liquid within the sludge is discharged from the passageway through the strainer member. The strainer member may be a suitable type of screen, which is well known in the industry, or may be a screen with a reinforced backing.
Alternatively, the strainer member may be a metal plate with suitable apertures formed therein.

' The li~uid that is discharged from the sludge passes through the screen and is collected in a longitudinal chamber.
The longitudinal chamber is defined by the strainer member and by an enclosing housing that is disposed around the strainer member, in operative relation thereto so as to receive and retain water passing throuyh the strainer member. The water is then pumped away through pipes that are in fluid communication with the chamber.

The solids or semi-solids that have been de-watered in the foregoing manner are removed from the passageway by the auger member, and are discharged through an outlet port into a suitable collection container, or onto a conveyor.

One problem with prior art strainer members, such as screens, is that they are easily damagedO Further, when they are damaged, they are expensive to replace, and also difficult to replace because they generally cover the entire passageway. It is therefore necessary to replace the entire strainer member.
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This often necessitates a great deal of disassembly of the separator device in order to change the entire strainer member and results in significant down time.

In order to overcome this problem, in part, U.S. Patent No. 5,008,010 discloses a rotating cylindrical screen-type filter used in a filtering device. While this filtering device is not a sludge de-watering device per se, liquids are solids are separated in a manner similar to de-watering devices. The strainer member disclosed in U.S. Patent No. 5,008,010 is longitudinally segmented so as to comprise a plurality of arcuate portions, which arcuate portions each extend the length of the strainer member. The arcuate portions connect together to form the entire annular strainer member. The segments of the strainer member can be replaced one segment at a time in the event that . the segments become damaged, or otherwise require replacement.
.,jl ;; However, U.S. Patent No. 5,008,010 does not disclose modular strainer members that are segmented along the length of the passageway, with the divisions that define the segments being generally transverse to the axis of the passageway. In such a segmented strainer member, single segments of the strainer member along the length of the passageway may be removed and replaced ~ independently of ths other segments.
'~ 25 Segmenting of the strainer member in this manner also allows for sectional design of the de~watering device, which is especially useful where the passageway could advantageously have

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various diameters, especially tapered sections. Moreover, it may be desirable for the sludge de-watering press device to have segments that are common between different design replications of the device. In this case, the same design of the filtering member can be used from device to device, for the common segments, thus allowing for a minimum of re-design.
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It is, therefore an object of the present invention to provide a modular strainer member for use in conjunction with a sludge de-watering press, which modular strainer member is divided transversely to its axis, along its length thereof.

It is another object of the present invention to provide a modular strainer member for use in conjunction with a sludge de-watering press, wherein the modular strainer member includes a housing therearound that is divided into a plurality of releasably connected modules along its length, the modules of the housing generally coinciding in longitudinal length with the module length of the strainer members.

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;: It is another object of the present invention to w provide a modular strainer member for use in conjunction with a sludge de-watering press, wherein segments of the modular strainer member can be used on different designs of the sludge de-watering press, along with appropriately newly designed se~ments, as necessary.

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'1 :' ~os~2s2 ~:i SUMMARY 0~ T~E INVE~TION
In accordance with the present invention there is provided, in a sludge de-watering press of the type having a housing defining a longitudinal chamber; a generally cylindrical strainer member positioned within the chamber in generally longitudinally aligned relation so as to define by its internal wall an elongated internal passageway in fluid communication adjacent one end with a sludge :inlet port and adjacent an c~ opposite other end with a sludge outlet port; an auger means operatively mounted in rotatable relation within the internal passageway with the outer spiral edge of the auger means in operative rotational contact with the internal wall; the strainer member being adapted to retain the relatively solid portion of the sludge within the elongated internal passageway between at least the inlet and outlet ports while allowing passage of the fluid portion of the sludge to flow away from the passageway into . the chamber upon compressive ad~ancement of the sludge along the internal passageway by the auger means; the improvement wherein:

:. 20 the housing is divided into a plurality of releasably connected modules along its length, the plurality of modules together defining the longitudinal chamber;
and the strainer member is divided transversely to its axis into a corresponding plurality of operatively ;~ 25 abutting segments, the corresponding plurality of segments together defining the internal passageway~
the segments being retained within the respective modules in operative, supported relation, so as to be .~ .
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respectively removable therefrom upon disconnection of but a single adjacent housing module.

Other objects, advantages, features and characteristics of the present invention, as well as methods of operation ind functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the lD accompanying drawings, the latter of which is briefly described hereinbelow.

BRIEF DESCRIPTION O~ T~E DRAWIN~S
Figure 1 is a side elevational view of a sludge de-watering press having the improved strainer member and housingof the present invention installed thereon;
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Figure 2 is a sectional side view of the sludge de-watering prPss of Figure 1, taken along section lines 2-2;

~i 20 Figure 3 is an exploded perspective view o~ the improved strainer member and housing of the present invention;

~ and, ,., ~,!.' 25 Figurz 4 is an exploded perspective view of an alternative embodlment of the improved strainer member of the present invention.
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'.' ;.5 DETAILED DESCRIP~ OF A PREFERRE:D EMBODIMENT
`.~1 Referring now to Figures 1 and 2 of the drawings, a .l sludge de-watering press, referred to by the general reference numeral 20, is shown in an installed configuration. The sludge de-watering press 20, is retained in an inclined configuration by a pair of leg members 21. The sludge de-watering press 20 has an inlet port 22 and an outlet port 24. Sludge is fed into the inlet port 22 and de-watered sludqe, typically called sludge i''$'~!
press cake, is discharged out of the sludge de-watering press 20 through the outlet port 24, as is well known in the industry.
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At the perimeter of the sludge de-watering press 20 is a housing 30 that encloses and defines, in part, a longitudinal chamber 32. Positioned within the longitudinal chamber 32 in generally longitudinally aligned relation thereto is a generally cylindrical strainer member 40, as best seen in Figure 3, which strainer member 40 has a centrally disposed longitudinal axis 41.
The longitudinal chamber 32 is defined as being the space between the generally cylindrical strainer member 40 and the housing 30.
The strainer member 42 is held in position within the housing 30 by spacer members 34a, 34b, which spacer members 34a, 34b abut against and generally support the strainer member 42 along the ,.
~ length thereof.

`~ 25 The internal wall 42 of the generally cylindrical strainer member 40 defines an elongated internal passageway 44, which passageway 44 is generally circular in cross-section. The internal passageway 44 is in fluid communication with the sludge i 0~292 inlet port 22, which is adjacent one end of the internal passageway 44, and is in fluid communication with the sludge outlet port 24, which is adjacent the opposite end of the internal passageway 44. In this manner, the sludge entering into Sthe inlet port 22 can be passed through the passageway 44 and discharged as sludge "press cake" through the outlet port 24.

Operatively mounted in rotatable relation within the internal passageway 44 is a progressive pitch auger means 50.
10The progressive pitch auger means 50 has an outer spiral edge 52, which edge 52 is in "operative rotational contact'i with the ,,, internal wall 42 of the generally cylindrical strainer member 40.
By the term "operative rotational contact", it is meant that the ~, outer spiral edge 52 of the auger means 50 either touches or 15almost touches the internal wall 42, so as to precl~de, as much as possible, sludge from seeping between the outer spiral edge ~-i 52 of the augQr means 50 and the internal wall 42, as the auger means 50 advances the sludge along the passageway 44.
,' ^i 20The strainer member 40 is adapted to retain the ~: relatively solid portions of the sludge within the elongated internal passageway 44, at least between the inlet port 22 and the outlet port 24 as the auger means 50 advances the sludge from the inlet port 22 toward the outlet port 24. The strainer member .~ 25 40 is further adapted to allow passage of the fluid portion of the sludge to flow therethrough, away from the passageway 44 and into the surrounding chamber 32, upon compressive advancement of the sludge along the internal passageway 44 by rotation of the ,.`.,1 ~ 8 ~ .

~a~,2~2 auger means 50.

The present invention comprises an improvement in the housing 30 and the strainer member 40, wherein the housing 30 is ,:, divided into a plurality of releasably connected modules along : its length. In the preferred embodiment illustrated, the housing ~ is so divided into three releasably connected modules, being ,.~
modules 30a, 30b, and 30c. The plurality of releasably connected modules 30a, 30b, 30c together define the longitudinal chamber ~ 10 32, as aforesaid. Further, the improvement comprises a strainer r~. member 40 that is divided transversely to its longitudinal axis 41 into a corresponding plurality of three operatively abutting segments 40a, 40b, 40c. The plurality of three segments 40a, 40b, 40c together define by their respective in$ernal wall the 15 internal passageway 44. The segments 40a, 40b, 40c are retained i~$~ within the respective modules 3Oa, 3Ob, 30c in operatively, : supported relation by the spacer members 34a, 34b. The spacer ~ members 34a are located at one end of each of the segments 30a, , 'I
30b, 30c and the spacer members 34b are located at the opposite 20 other end o~ each of the segments 30a, 30b, 30c. 3uxtaposed ones of the spacer members 34a, 34b abut in intimate contact with each other so as to preclude passage of liquid, or even sludge, therebetween. The juxtaposed spacer members are operatively received and retained in place by clamping members 35, which 25 clamping members 36 have first 36a and second 36b portions held securely together by bolts 38 and cooperating nuts 39. The term "operatively abutting segment" refers to the manner in which the segments 40a, 40b, 40c are interconnected one to another along ~, _ g _ ',~

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2 0 9 ~ 2 9 2 ~, ., the length of the passageway 44. It is not necessary that the segments 40a, 40b, 40c actually interconnect with one another.
It is preferable, however, that the edges of the segments 40a, 40b and 40c abut against one another so as to substantially form a seal therebetween to preclude the escape of sludge therethrough. It is not necessary, however, that juxtaposed segments abut each other if the spacer members 34a, 34b by their ;~ contacting design preclude the passage of liquid from between the joints of the spacer members 34a, 34b.

Each of the segments 40a, 40b, 40c is removable from the sludge de-watering press upon disconnection of the respective corresponding single adjacent housing module 30a, 30b, 30c, which disconnection may be accomplished by first removing the appropriate of the bolts 38 and nuts 39. In this manner, in order to inspect one of the segments 4Oa, 40b, 40c, it is :,j necessary to disconnect and remove only the corresponding housing module. In order to remove and replace one of the segments 40a, 40b, 40c it is necessary to disconnect and remove the corresponding housing module. In the case of removing and ~ replacing segment 40b, the middle segment, one other module and :.,j one other segment would each need to be removed in order to allow the segment 40b to be slid off the end of the module. None of the other strainer member segments need to be replaced if there is damage to one strainer member segment only.
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In the preferred embodiment, the operatively abutting ~ segments 40a, 40b, 40c of the strainer member 40 are of an ,~ - 10 -'`'':i ,';.
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2 0~ ~2~2 " .,i, annular shape such that each segment encompasses an entire radial band around the internal passageway 44. Such annular segments ,' .1 40a, 40b, 40c provide for a relatively strong strainer member 40, which is desirable in order to resist the forces generated due to the compression of the sludge within the passageway 44, by the compressive advancement of the auger means 50. The operatively abutting segments 40a, 40b, 40c preEerably comprise solid metal sheets having a plurality of apertures 46 therein, which apertures 46 are formed by drilling.

In the preferred embodiment illustrated, the operatively abutting segments 40a, 40b, 40c are each of a progressively reduced diameter from the sludge inlet port 22 to l the sludge outlet port 24. Each of the segments 40a, 40b, 40c may be tapared a different amount than the other of the segments 40a, 40b, 40c. Further, the segments, 40a, 40b, 40c may be of a non-constant taper. Correspondingly, the diameter of the outer spiral edge 52 of the auger means 50 is of a proportionately reduced diameter along its length, so as to maintain operative rotational contact with the internal wall 42 of each of the ~ segments 40a, 40b, 40c. Such progressive reduction in the -~ diameter of the segments allows for compressive advancement of the sludge along the ent.ire length of the passageway 44, such that the sludge is compressed by a designed amount at any point along the passageway 44.

It will be understood that numerous variations as will occur to those skilled in the art may be made to the above-',', J.. ,.,! ' ' ,, ' ` :l , ~
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. i described apparatus and method embodiments of the invention without departing from the claimed scope of the invention. For example, in one alternative embodiment, as shown in Figure 4, it is contemplated that each segment 62 of the strainer member 60 ; 5 is itself longitudinally divided into a second plurality of ,., ;i radially abutting arcuate strainer panels 62a - 62d. The radially abutting arcuate strainer panels 62a - 62d together define the respective segment 62. Each of the segments 62 are individually retained within the respective housing module in .
operative, supported relation, as are the segments 40a, 40b, 40c ~3 in the preferred embodiment. The arcuate strainer panel 62a -,.~
62d are individually removable from the sludge de-watering press !~ for repair or replacement upon disconnection of but the respective single adjacent housing module.
In another alternative embodiment, it is contemplated that each of the segments of the generally cylindrical strainer member are each of substantially the same cross-sectional . ., diameter between the sludge inlet port 22 and the sludge outlet port 24 of the sludge de-watering press. The diameter OI the auger spindle may or may not increase in diameter along its length from the sludge inlet port 22 to the sludge outlet port .,~ .
3 24 in order to increase the compressive forces on the sludge in :. :
the internal passageway 44.
In yet another alternative embodiment, it is contemplated that juxtaposed ones of the segments 40a, 40b, 40c do not actually abut one another. Instead, the juxtaposed ones ~i~
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i3~9 ., of the segments 40a, 40b, i~Oc abut against a portion of the spacer members 34a, 34b, which spacer members 34a, 34b are disposed in interposed abutting relation between juxtaposed .. .
~; segments 4Oa, 4Ob, 40c.
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In yet another alternative embodiment of sludge de-watering press according to the invention, it is contemplated r~ that at least the strainer member s,egment closest to the sludge outlet port is of a reduced cross-sectional diameter than the remainder of the corresponding plurality of the strainer member segments. The diameter of the outer spiral edge of the auger means is proportionately reduced along the length of the respective module so as to maintain the operative rotational contact with the internal wall of the segment. The strainer member segment closest to the sludge outlet port may be of a constant cross-sectional diameter that is a reduced diameter compared to the diameter of the other strainer member segments.
In this manner, a "stepped" strainer member is realized.

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Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY
OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. In a sludge de-watering press of the type having:
a housing defining a longitudinal chamber;

a generally cylindrical strainer member positioned within the chamber in generally longitudinally aligned relation so as to define by its internal wall an elongated internal passageway in fluid communication adjacent one end with a sludge inlet port and adjacent an opposite other end with a sludge outlet port;

an auger means operatively mounted in rotatable relation within said internal passageway with the outer spiral edge of said auger means in "operative rotational contact" with said internal wall;

the strainer member being adapted to retain the relatively solid portion of said sludge within the elongated internal passageway between at least said inlet and outlet ports while allowing passage of the fluid portion of said sludge to flow away from said passageway into said chamber upon compressive advancement of said sludge along said internal passageway by said auger means;

the improvement wherein:

said housing is divided into a plurality of releasably connected modules along its length, said plurality of modules together defining said longitudinal chamber;
and, said strainer member is divided transversely to its axis into a corresponding plurality of "operatively abutting segments", said corresponding plurality of segments together defining said internal passageway, the segments being retained within the respective modules in operative, supported relation, so as to be respectively removable therefrom upon disconnection of but a single adjacent housing module.

2. The sludge de-watering press of claim 1, wherein said auger is a progressive pitch auger.

3. The sludge de-watering press of claim 1, wherein said segments are each of substantially the same cross-sectional diameter between said sludge inlet port and said sludge outlet port.

4. The sludge de-watering press of claim 1, wherein at least the segment closest to said sludge outlet port is of a reduced cross-sectional diameter than the remainder of said corresponding plurality of segments, and the diameter of said outer spiral edge of said auger means is proportionately reduced along the length of the respective module so as to maintain said operative rotational contact with the internal wall of said segment.

5. The sludge de-watering press of claim 1, wherein said internal passageway defined by said plurality of operatively abutting segments is of progressively reduced diameter from said sludge inlet port to said sludge outlet port, and the diameter of said outer spiral edge of said auger means is of proportionately reduced diameter along its length so as to maintain said operative rotational contact with the internal wall of each of said segments.

6. The de-watering press of claims 1 or 5, wherein each of the segments is itself longitudinally divided into a second plurality of radially abutting arcuate strainer panels together defining the respective segment, the segments being individually retained within the respective housing module in operative, supported relation, so as to be individually removable therefrom for repair or replacement upon disconnection of but a single adjacent housing module.

7. The de-watering press of claim 1, wherein said internal passageway is generally circular in cross-section.

8. The filter member of claim 7, wherein said plurality of operatively abutting segments are of an annular shape such that each segment encompasses an entire radial band around said internal passageway.

9. The filter member of claim 1, wherein said plurality of operatively abutting segments comprise solid metal sheets having a plurality of apertures therein.

10. The filter member of claim 9, wherein said apertures in said plurality of operatively abutting segments are formed by drilling.

11. The filter member of claim 1, wherein said strainer member is divided into three operatively abutting segments.