US1888743A - Sedimentation apparatus - Google Patents

Description

Nov. 22, 1932. c. H. sco'r'r SEDIMENTATION APPARATUS Filed Feb 23, 1932 4 Sheets-sheaf. 1

INVENTOR CHARLES BY SCOTT ATTORNEY Nov. 22, 1932. c. H. SCOTT SEDIMENTATION APPARATUS Filed Feb; 23, 1932 4 Sheets-Sheet 2 INVENTOR (HA/{LES H.sc0rr BY ATTORNEY Nov. 22, 1932. c. H. sec-r1- SEDIIIENTATION APPARATUS Filed Feb. 25. 1932 4 Sheets-Sheet 3 INVENTOR CHARLES H. SCOTT ATTORNEY Nov. 22, 1932. c. H. SCOTT SEDIMENTATION APPARATUS Filed Feb. 23, 1932 4-Sheets-Sheet 4 INVENTOR CHARLES H. SCOTT ATTORNEY Patented Nov. 22, 1932 UNITED STATES :PATENT OFFICE CHARLES H. SCOTT, OF EDGE-WATER, COLORADO, ASSIGNOR TO THE DORE COMPANY, INC., F YORK, N. Y., A CORPORATION OF DELAWARE SEDIMENTATION APPARATUS Application filed February 23, 1932. Serial No. 594,441.

This invention relates to sedimentation apparatus of the type of thickeners or clarifiers in which solids suspended in liquids are settled to the bottom of the clarifier'by -sedimentation wherein the settled solids in the ,form of sludge are raked to a central sludge discharge. The rakes depend from more or less radially extending rake arms which are propelled from a rotatable vertical support.

More particularly, the invention relates to.

the arrangement of the vertical rotatable support mechanism and the means for rotating said support.

The object of the invention is to devise an arrangement for operating the sludge discharge rakes in a manner which avoids the necessity of any overhead supporting truss or bridge which has been' considered necessary heretofore in clarifiers of this type. That is, one object of the invention is tomake the clarifier more sightly. Another object is to so simplify the sludge discharge drive mechanism,.that the cost of its construction will be reduced.

To that end the invention includes among other things the provision of a center shaft, pier or column upstanding from the bottom of the clarifier which is used to form the support for a rotatable sleeve or drum which carries the sludge dischar e rake mechanism.

At the same time, the p1er is used as a support for the motor devices for driving the rotatable drum and;its slud e raking mechanism. This is accomplishef by providing on the pier a platform or framework from which the rotatable drum can depend and from which the motordevices and gearin can be mounted. Alsothe invention inclu es making the center pier hollow and using it as a 2 part of a siphonic central feed to the clarifier.

Thus, the center pier is caused to serve a number of useful purposes.

' I have illustrated in the accompanylng drawings one embodiment of the invention which is the best of which I am at present in formed. In these drawings, Figure 1 is an elevational view, with parts in section and with parts broken away, of a clarifier showing the invention as applied thereto; Figure 2 1s a plan view of a clarifier with my 1mroved sludge discharge driving mechanism; igure 3 is a plan view, with parts in section of the platform from which the rotatable drum depends and on which the motor devices are located; Figure 4 is a vertical sec-' tional view of a detail of the gearing mechanism for the drum in the'manner of the drum support; Figure 5 is a partial sectional view with parts broken away showing the feed distributing slots; while Figure 6 is a diagrammatic showing of siphonically feeding a plurality of adjacent clarifiers.

In sedimentation devices such as clarifiers, thickcners or sewage digesters, it is customary to have a tank 11 for holding the liquid from which solids in suspension are to be removed, provided with a side wall 12 and a bottom 13. Solids settling to the bottom 13 by sedimentation take the form of sludge which is raked or impelled by slowly moving rake blades 14 toward a bottom sludge discharge hopper 15 from which the sludge is removed through a discharge pipe 16. r

The rake blades 14 are usually supported or depend from rake arms 17 which extend more or less radially from a central vertical rotatable support 18 and the rake arm 17 may be braced by tension rods or baces 19.

In the present invention, the vertical support 18 is in the form of a drum, shell, sleeve, structural frame, or cage which encircles a central column pier or shaft 20 upstanding from the bottom 13 of the clarifier tank. The center pier 20 extends upwardly above 7 the normal liquid level 21 in the clarifier and 85 is provided with a platform 22 supported from a stationary-framework 45 forming substantially an extension of the pier. To this platform or framework extends a bridge 23 from the periphery orwall 12 of the clarifier to provide a walkway for the 0 erator to the platform 22 to'inspect the mec anism mounted thereon. The bridgcor' walkway 23 may be used to house the necessary electric wiring 24 to convey power to the operating mechanism and it may or may not also be used to support a feed launder for the incoming liquid to be treated in the clarifier.

The feed under some circumstances may be brought in by a radial feed launder so that it I is fed to the clarifier centrally thereof, or under other circumstances the feed to the clarifier ma be arranged peri herally of the clarifier. I Iowever, my pre erred form of feed is by means of an inverted siphon 25 extending upwardly through the pier 20, which in pulley or sprocket 30; belt or chain 31; and

pulley or sprocket 32; and a shaft 34 suitably supported on the framework which is r0- vided with a worm gear 35 meshing wit a horizontal gear 36 carried by vertical shaft 37. This shaft has keyed to it a gear 38 meshing with a bull or ring gear 39, from which is dependingly supported the drum 18, which is preferably secured to the gear 39 by means of a flanged turn-table or ring 40. The motor 28 and speed reducer 29 may be suitably housed by casing 41, and the pulley 32 may also be housed by casing 42. A further casing 43 may protect the horizontal gear 36 while the shaft 37 may be suitably housed and journaled at 44. i

The turn-table 40, carrying the drum 18, is supported from the framework or turntable base 45 (which also includes journal 44 and flange 60) secured in position on the pier 20 4 in any suitable manner. The base 45 also supports the platform 22. The shaft may have lubricating connections such as at 46. The drum 18 may be suspended from the turntable 40 by means of channel-irons 47 spaced apart to form the slotted openings 27. These channel-irons have flanges 48. One or more of the channel-irons may be extended as at 49 to reenforce the drum' 18 against thrust thereon exerted by the sludge raking mechanism. 7

Under certain circumstances, it is desirable to indicate any abnormal load which may come on the sludge discharge mechanism so for that purpose there is applied at the end of the shaft 34 an overload alarm device 50. This is arranged by having the shaft 34 mounted for slight longitudinal movement in its bearings 51 and 52,.but a spring 53 is provided in a supporting frame 54 which normally tends to prevent longitudinal displacement of the shaft 34. If an abnormal load comes on the drive mechanism, the shaft 34 will be displaced longitudinally against the pressure of the spring 53 and this displacement of the shaft operates a pivoted pointer 55 which shows on a scale 56 that the pointer has passed the position of normal operation. The pointer may also be used to Operate a visible or audible signal to the operator, that abnormal conditions exist.

Liquid from which suspended solids have been settled overflows into a peripheral outlet 57 after first getting past a bafile or weir 58 and then flows from the efiluent launder 57 through the outlet pipe 59. 60 indicates a bracket arrangement forming part of the turntable base or framework 45, which suphollow portion 62 forming one leg of a siphon 25, and connecting to the hollow portion the remaining portion of the siphon 25. The siphon is of course fed from a source of supply of the liquid to be treated in a clarifier located higher than the liquid level in the clarifier. The liquid from the leg 62 of the siphon within the pier 20 exits therefrom through slotted openings 26 in the pier. The slotted openings 27 in the drum 18 are alignable with the openings 26 to enable the feeding material to pass through the revoluble drum 18 to be treated in the clarifier.

Where several clarifiers are to be used, they can be arranged as diagrammatically shown in Fig. 6 wherein 64, 65, 66 and 67 represent clarifiers, each provided with a.

hollow central pier 20. 68 indicates the channel containing liquid to'be treated in the clarifiers leading to a disturbing basin 69 from which a siphonic feed 25' leads to each clarifier. A valve or other flow controlling device 70 is provided for each siphonic feed whereby feed from the basin 69 can be selectively supplied to any or all of the clarifiers. As the liquid level in the basin 69 is maintained above the liquid level ,in the clarifiers, it furnishes suflicient hydrostatic head to siphon the feed from the basin into the clarifiers.

Operation The liquid with its solids in suspension to be clarified orthickened by sedimentation is flowed into the sedimentation tank 11 in a I continuous manner and the carified liquid is flowed therefrom as efiluent in a continuous manner. Solids settling out of the liquid fall to the bottom of the clarifier in the form of sludge and are collected by blades 14 which are moved by means of the rake arm 17 which are rotated by the central vertical rum 18 equipped with ed on the turn-ta le base or framework supported on the central pier. The drum 18 depends from a turn-table 40 deriving its support from the bracket arrangement 60 forming a part of the turn-table base 45 and is preferably supported on an anti-friction device 61. The turn-tables 40 from which the drum 18 depends is provided with a bull ring or gear 39 which is driven by means of suitable gearing from the motor 28.

Operation of the motor 28, through the speed reducer 29, shaft 34 and worm gear 35, causes gear 36 to rotate vertical pinion 37 with its gear 38, and gear 38 meshing with bull gear 39 rotates the turn-table 40 from which the drum 18 depends. Rotation of drum 18 with its rake arms and rakes causes settled sludge to be conveyed to the sludge discharge 15.

This arrangement of center pier, center drive for the sludge discharge mechanism also lends itself to the central siphonic feed to the clarifier. The feed from a suitable source of supply which is at a level above the liquid level in the clarifier flows through the siphon 25 up through the hollow central pier 20 and out therefrom through the slots 26, the height of the supply above the liquid level in the clarifier being suflicient to provide the necessary hydrostatic head. It will be recalled that the drum 18 revolves, so slots 27 are provided in it which, during its rotation, intermittently register with the slots 26 in the pier extension 45 in order that the feed from the s ots 26 can pass through the drum into the clarifier through the slots 27 This arrangement is found to be doublv advantageous, in that the rotation of the drum has a helpful distributing effect upon the feed passing through the slots 27 therein. The fins or flanges 48 associated with the slots 27 in the drum 18 aid in difi'using the sewage flowing through the slots into the body of liquid in the clarifier. Where it is desired to feed siphonically to a group of this can be done by the arrangement shown in Figure 6 and described above.

It will thus be seen that the invention provides a neat and compact arrangement for driving the sludge discharge mechanism of a thickener, clarifier or digester in a manner that is cheap to build, is attractive in appearance and is practically fool-proof. The embodiment described is shown in an illustrative sense for the purpose of showing in what-manner the invention ma be carried out and not in a limiting sense or obviously many modifications may be made in the embodiment shown herein without departin from the spirit and scope of the appended claims.

I claim:

1. A sludge discharge operating mechanism for a sedimentation tank comprising an upstanding pier in the tank, a flanged ring rotatably mounted on said pier, a drum depending from said ring, a motor supportedfrom said pier, a driving gear connection between said motor and said ring for rotating said ring and its depending drum, and sludge rakes operated by rotation of said drum.

2. Sedimentation apparatus havin a tank with a sludge discharge, sludge disc arging rakes; and means for operating said rakes comprising a pier, a rotatable drum supporting said rakes, a motor, and a driving connection between said motor and said drum, and a stationary frame work on said pier having the combined function of supporting said motor, said driving connection and said drum.

3. Sedimentation apparatus having a tank with a sludge discharge, sludge discharging rakes; and means for operating said rakes comprising a pier, a framework arrangement forming an extension of said pier mounted thereon, a drum carrying said rakes rotatably depending from said framework, a motor and a driving connection between said motor and drum, said framework supporting said motor, said driving connection and said drum.

4. Sedimentation apparatus having a tank with a sludge discharge, sludge discharging rakes; comprising a pier, a framework arrangement thereon, a drum carrying said rakes rotatably depending from said framework, a motor, a worm gear driven thereby, a gear driven by said worm gear, a vertical pinion secured to said gear passing through said framework, a gear thereon below said framework, and a bull gear on said drum below said framework with which meshes said gear on said pinion below said framework.

5. Sedimentation apparatus havin a tank -with a sludge discharge, sludge disc arging rakes, a central feed for said tank; and combined means for operating said rakes and housing said feed comprising a hollow pier,

and means for operating said rakes ILL,

a rotatable drum supporting said rakes, a

ment supported from and encircling said I pier, sludge rakes operated by rotation of said drum, a ring gear associated with said drum, a stationary motor supported from said pier, and a gear connection between said stationary motor and said ring ear for r0- tating said drum through the me ium of said ring ear.

7. sedimentation tank havin a hollow center pier through which liquid is discharged into the tank, a driven rotatable drum encircling said pier, sludge raking devices associated with said drum, and means for distributing liquid discharging from said pier comprising slots in said drum.

8. A sedimentation tank having a hollow center pier through which liquid is discharged into the tank, a driven rotatable drum encircling said pier, sludge raking devices associated with said drum, and means for distributing liquid discharging from said pier comprising slots in said drum and fins extending substantially radially from said drum.

9. A sedimentation tank having a hollow center pier through which liquid is fed to the tank, a slotted extension on said pier through which liquid is discharged from the pier into the tank, a driven rotatable drum encircling said pier, sludge raking devices associated with said drum, and means for gassing radially through said drum liquid ischarging from said slotted extension.

10. Apparatus of the type described comprising a sedimentation tank, an upstanding pier in said tank, a rotatable element supported from and encircling said pier, sludge rakes operated by rotation of said element, a ring associated with said element, a platform mounted from said pier, a stationary motor supported from said platform, and a drive connection between said motor and said ring for rotating said drum through the medium of said ring. V

In testimony whereof I have afiixed my signature to this specification. ,7 CHARLES H. SCOTT.

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