7 169 312

7,169,312 Title:

Methods of and apparatus for collecting sludge from the floor of a settler basin

A system meets material collection needs by significantly increasing the flow rate through a header that collects sludge. Telescopic pipes stay in a line adjacent to the bottom of a basin and do not float upwardly into or against equipment in the basin. A bearing is configured in a radial space between the pipes and with a central axial sludge collection opening, and adjacent to the header. The sludge collection opening allows sludge flow into the pipes, the flow having a value not less than a minimum flow. This flow is into system from immediately around the pipes configured in the telescopic relationship.

What is claimed is:

1. A system for collecting material from a bottom of a material settling container, comprising: a first rigid pipe, the first rigid pipe having a first opening; a secondrigid pipe, the second rigid pipe having a first open end; the first and second pipes being in telescopic relationship with one pipe received within the other pipe in an overlapping relationship so that the first and second pipes cooperate to define amaterial collection conduit, wherein a first portion of the material collection conduit extends axially between the first opening and the first open end, the first portion being configured to define a radial clearance between the first pipe and thesecond pipe and to extend axially between the first opening and the first open end; and a bearing received in the radial clearance between the first pipe and the second pipe and located axially between the first opening and the first open end, thebearing being configured in cross-section to cooperate with the inner pipe to define a material collection opening, the cross-sectional configuration of the bearing being such that with the inner pipe received in the bearing the material collectionopening allows a flow of collected material having a value not less than a minimum flow to flow centrally and axially through the radial clearance from the first open end of the second rigid pipe to the first opening of the first pipe.

2. A system for collecting material as recited in claim 1, wherein: the minimum flow is sufficient to collect material from immediately around the pipes in the telescopic relationship so that normal material collection movement of the secondpipe is not impaired.

3. A system for collecting material as recited in claim 2, the system further comprising: a header connected to the second pipe and provided with first plurality of openings through which to receive material from across a lateral width of thematerial settling container; and wherein the bearing is configured so that with the first pipe received in the bearing a first area of the material collection opening has a value of about two area units, and a second area that comprises the total ofindividual areas of all of the first plurality of openings of the header has a value of about fourteen area units, and the first area is related to the second area by an area ratio of about 2 to 16 to allow the flow to be sufficient to collect materialfrom immediately around the pipes in the telescopic relationship so that normal material collection movement of the second pipe is not impaired.

4. A system for collecting material as recited in claim 1, the system further comprising: a first header secured to the second pipe adjacent to the first bearing, the first header having a first plurality of openings through which to collectthe material, the header defining a header conduit extending from the first plurality of openings to the material collection conduit; wherein a first area of the material collection opening is proportional to a second area, the second area comprises atotal of individual areas of all of the first plurality of openings in the header, and wherein the first area is proportional to the second area according to an area ratio comprising a numerator equal to the first area and a denominator comprising thesum of the first area and the second area.

5. A system for collecting material as recited in claim 4, wherein: the area ratio is about 0.125.

6. A system for collecting material as recited in claim 4, wherein: the second pipe further comprises a second open end; the first opening is received in the second pipe spaced from the first open end and spaced from the second open end; andthe first pipe extends outside of the second pipe so that a first portion of the first pipe is adjacent to and outside of the first open end and a second section of the second pipe is adjacent to the second open end; the header is a first header and thebearing is a first bearing; the system further comprising: a second of the two headers, each of first and second headers having about fourteen openings through which to collect the material, the first header being secured to the second rigid pipeadjacent to the first open end and adjacent to the first section, the second header being secured to the second rigid pipe adjacent to the second open end and adjacent to the second section; and a second of the two bearings, the second bearing beingreceived in the radial clearance between the first pipe and the second pipe and located axially between the first opening and the second open end, the second bearing being configured in cross-section to cooperate with the first pipe to define a secondmaterial collection opening; wherein the cross-sectional configuration of each bearing is such that with the first pipe received in the first bearing and in the second bearing, each of the first and second material collection openings allows a flow ofcollected material having a value of not less than the minimum flow to flow centrally and axially through the radial clearance into the second pipe; and wherein the cross-sectional configuration of each of the bearings is such that with the first pipereceived in the first bearing and in the second bearing each of the first and second material collection openings has a first cross-sectional area that provides an area ratio of about 0.125 with respect to the sum of the first area and a total of thecross-sectional areas of the fourteen openings of the header that is adjacent to the respective bearing.

7. A system for collecting material as recited in claim 4, wherein: each of the openings of the first plurality of openings has an area having a value of about one area unit and the total area of the first plurality of openings is aboutfourteen area units; and the material collection opening is configured to have a cross-sectional area having a value of about two area units.

8. A system for collecting material as recited in claim 1, wherein: the configuration of the bearing is such that the material collection opening is co-extensive with part of the first portion of the material collection conduit; and theminimum flow is sufficient to collect material outside the first pipe and outside the second pipe, the collection being from immediately around the inner pipe so that normal material collection movement of the second pipe is not impaired by materialthat, in the absence of the material collection opening, would build-up centrally relative to the pipes.

9. A system for collecting material as recited in claim 1, wherein: the second pipe is configured with a second open end; and the first opening is a second open end, the second open end being received in the second rigid pipe axially spacedbetween the first open end and the second open end.

10. A system for collecting material as recited in claim 1, wherein: the second pipe further comprises a second open end; the first opening is received in the second pipe spaced from the first open end and from the second open end; thebearing comprises a first bearing received in the radial clearance between the first pipe and the second pipe and axially received between the first opening and the first open end, the first bearing being configured to cooperate with the first pipereceived in the first bearing to define a first one of the material collection openings located axially between the first opening of the first rigid pipe and the first open end of the second pipe, the first material collection opening allowing the flowto be a first flow having a value of no less than the minimum flow to flow through the first material collection opening; and the bearing comprises a second bearing received in the radial clearance between the first pipe and the second pipe and axiallyreceived between the first opening and the second open end, the second bearing being configured to cooperate with the first pipe received in the first bearing to define a second one of the material collection openings located axially between the firstopening and the second open end of the second, the second material collection opening allowing a second flow having a value of no less than the minimum flow to flow through the second material collection opening.

11. A system for collecting material as recited in claim 10, the system further comprising: a first header secured to the second pipe adjacent to the first bearing, the first header having a first plurality of openings through which to collectthe material, the first header defining a first header conduit extending from the first plurality of openings to the material collection conduit; a second header secured to the second pipe adjacent to the second bearing, the second header having a firstplurality of openings through which to collect the material, the second header defining a second header conduit extending from the first plurality of openings to the material collection conduit; wherein a first area of each of the material collectionopenings is proportional to a second area, the second area comprises a total of individual areas of all of the first plurality of openings of each of the headers, and wherein each of the first areas is proportional to each of the second areas accordingto an area ratio comprising a numerator equal to the first area and a denominator comprising the sum of the first area and the second area.

12. A system for collecting material as recited in claim 11, wherein: each of the area ratios is about 0.125.

13. A system for collecting sludge from a bottom of a basin on which the sludge settles, comprising: an inner rigid pipe, the inner pipe having a first opening; an outer rigid pipe, the outer pipe having an open end; the inner and outer pipesbeing in telescopic relationship to define a sludge collection conduit, wherein a first portion of the sludge collection conduit extends axially between the first opening and the open end, the first portion being configured as a sludge passagewayextending radially between the inner pipe and the outer pipe and axially between the first opening and the first open end; a header secured to the outer pipe adjacent to the open end, the header having a first plurality openings through which to collectthe sludge from across a lateral width of the basin except from axial locations adjacent to the inner and outer pipes in the telescopic relationship, the header defining a header conduit extending from the first plurality of openings to the sludgecollection conduit; and a bearing received in the sludge passageway radially between the inner pipe and the outer pipe and axially between the first opening and the open end, the bearing promoting normal sludge collection movement of the outer piperelative to the inner pipe even though sludge tends to collect immediately around the inner pipe, the bearing being configured to cooperate with the inner pipe to define a sludge collection opening located axially between the first opening of the innerpipe and open end, the sludge collection opening allowing a flow of collected sludge from the open end and through the sludge passageway to the first pipe; wherein the flow has a value of not less than a minimum flow of collected sludge through thesludge collection opening to the sludge passageway of the sludge collection conduit, and wherein the minimum flow is sufficient to collect enough sludge from the locations immediately around the inner pipe so that the normal sludge collection movement ofthe outer pipe is not impaired notwithstanding the tendency of the sludge to build-up around the inner pipe.

14. A system for collecting sludge as recited in claim 13, wherein: a first area of the sludge collection opening is related to a second area and the second area comprises a total of individual areas of all of the first plurality of openings,wherein the first area is related to the second area by an area ratio, the area ratio being a ratio of the first area to the sum of the first area and the second area, the area ratio being about 2 to 16.

15. A system for collecting sludge as recited in claim 13, wherein: the outer pipe includes a second open end; the first opening of the inner pipe is spaced axially from the first open end and the second open end; and the bearing comprises afirst bearing received in the sludge passageway radially between the inner pipe and the outer pipe and axially between the opening and the first open end, the first bearing being configured to receive the inner pipe and define a first one of the sludgecollection openings axially between the first opening and the first open end, the first sludge collection opening allowing a first flow of collected sludge through the sludge passageway; and the bearing comprises a second bearing received in the annularsludge passageway radially between the inner pipe and the outer pipe and axially between the first opening and the second open end, the second bearing being configured to receive the inner pipe and define a second one of the sludge collection openingsaxially between the first opening and the second open end, the second sludge collection opening allowing a second flow of collected sludge through the passageway; and wherein the configuration of the first and second bearings is such that each of therespective first and second sludge collection openings allows a flow having a value of not less than the minimum flow of collected sludge flow through the respective sludge passageway.

16. A system for collecting sludge as recited in claim 13, wherein: a header opening area comprises a total of the individual areas of all of the first plurality of openings in the header; a first area of the material collection opening isproportional to the header opening area and the first area is proportional to the header opening area according to an area ratio comprising a numerator equal to the first area and a denominator comprising the sum of the first area and the header openingarea.

17. A system for collecting sludge as recited in claim 16, wherein the area ratio is about 0.125.

18. A method of collecting sludge from a settling volume, the method comprising the operations of: mounting inner and outer rigid pipes in a telescopic relationship, the inner pipe being received within the outer pipe in an overlappingrelationship so that the pipes cooperate to define a sludge collection conduit adjacent to a bottom of the settling volume, defining a first opening in the inner pipe, the first opening being received inside the outer pipe; defining an outlet end of theinner pipe; defining an open end of the outer pipe; and configuring a bearing for reception in the outer pipe so as to maintain the sludge collection conduit in an open condition at a location axially spaced from the open end and from the firstopening, the configuring operation facilitating sludge collection movement of the outer pipe relative to the inner pipe, the sludge collection movement being into the sludge on the bottom of the settling volume, the configuring operation allowing asludge flow having a value of not less than a minimum flow of collected sludge to flow through the sludge collection conduit in an open condition.

19. A method as recited in claim 18, wherein: the configuring operation configures the bearing and the inner pipe so that the minimum flow is sufficient to collect the sludge from immediately around the inner pipe so that normal sludgecollection movement of the outer pipe is not impaired by sludge build-up immediately around the inner pipe.

20. A method as recited in claim 18, the method further comprising the operations of: attaching a header to the outer pipe, the header having a plurality of sludge inlet orifices for collecting sludge from the bottom of the volume and away froma volume immediately around the inner pipe; defining the sludge collection conduit maintained in the open condition as having a selected area; and configuring areas of the orifices so that a ratio of the selected area to a sum of the selected area anda total area of the orifices is in a ratio of about 2 to 16.

21. A method as recited in claim 18, further comprising the operation of: applying a lower-than atmospheric pressure to the outlet end of the inner pipe, the applying operation urging the sludge to flow into the plurality of sludge inletorifices from the volume and away from immediately around the inner pipe, the applying operation further urging the sludge to flow from the bottom and from the volume immediately around the inner pipe into the open end, the sludge being further urged toflow through the sludge collection conduit that is in the open condition.