Scum collector

May 23, 1939.

2,159,409

Μ. B. TARK

SCUM COLLECTOR

Filed July 15, 1935 7 Sheets-Sheet 1

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May 23, 1939.

2,159,409

Μ. B. TARK

SCUM COLLECTOR

<img file="US2159409A_D0002.tif" />

May 23, 1939. m. _B. _TARK 2,159,409

SCUM COLLECTOR

Filed July 15, 1935 7 Sheets-Sheet 3

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May 23, 1939.

MB. TARK

SCUM COLLECTOR Filed July 15, 1935

2,159,409

Sheets-Sheet 4

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May 23, 1939. m. _{B TARK} 2,159,409

SCUM COLLECTOR

Filed July 15, 1935 7 Sheets-Sheet 5

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<img file="US2159409A_D0007.tif" />

May 23, 1939.

2,159,409

Μ. B. TARK

SCUM COLLECTOR

Filed July 15, 1935 7 Sheets-Sheet 6

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May 23, 1939.

Μ. B. TARK

2,159,409

SCUM COLLECTOR

Filed July 15, 1935 7 Sheets-Sheet 7

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Patented May 23, 1939

2,159,409

UNITED STATES PATENT OFFICE

2,159,409 SCUM COLLECTOR

Marcus B. Tark, Philadelphia, Pa., assignor to Link-Belt Company, Chicago, Hl., a corporation of Illinois

Application July 15, 1935, Serial No. 31,419

Claims. (Cl. 210—3)

This invention relates to equipment for removing grease, oil and other floating material from settling tanks for sewage and industrial wastes and in the form illustrated herewith comprises 6 a series of tanks associated and in communication with each other and comprising means for moving settled material and material floating upon or suspended near the surface of liquid within the tank.

1® It has for one object to provide means whereby the surface of a body liquid may be swept of scum by simple mechanisms which are caused to sweep the entire surface. Another object is to provide a scum collector or skimmer and a sludge

I⁵ collector for collecting, respectively, scum and sludge from a plurality of tanks and for moving them to a discharge. Another object is to provide a machine that collects the scum, concentrated at one end of the tank by another collector, 20 and discharges it into a trough with a minimum amount of moisture. Another object is to provide automatic means for controlling the skimmer so that in one direction of reciprocation it is in contact with the surface of the liquid and collects 25 the scum, while in the opposite direction of reciprocation it is automatically raised and held out of contact with the liquid. Other objects will appear from time to time throughout the specification and claims.

The invention is illustrated more or less diagrammatically in the accompanying drawings, wherein:

Figure 1 is a longitudinal, generally vertical, sectional view of a tank with the scum collector 35 installed;

Fig. 2 is a plan view on an enlarged scale, showing a portion of the tank and one collecting assembly;

Fig. 3 is a side elevation showing one of the 40 collector assemblies at the scum trough taken on an enlarged scale and with parts of the tank shown in section;

Fig. 4 is a side elevation showing one of the collector assemblies at the end of the tank With 45 parts of the tank in section;

Mg. 5 is a section on the line 5—5 of Mg. 3;

Mg. 6 is a plan view of a tank assembly;

Mg. 7 is a transverse vertical section with parts omitted, taken at line 7—7 of Mg. 6; and

Mg. 8 is a longitudinal vertical section taken at line 8—8 of Mg. 6, showing the sludge cross collector*

Mg.’ 9 is a view similar to Mg. 1 showing a duplicate installation with one drive operating four 55 scum collecting carriages.

Like parts are designated by like characters throughout the specification and drawings.

In the form shown the collector is applied to a generally rectangular,’ elongated tank. It is not, however, limited to this application nor in 5 fact to any particular size or shape of tank. As shown the tank comprises end walls i, a floor or bottom wall 2, and side walls 3. A main partition wall 4 may be installed dividing the tank in the form here shown, into two sections of sub- 1® stantially equal length. Partial partitions or baffles 5 may also be installed at suitable points throughout the tank. These details are illustrated diagrammatically and form no essential part of the present invention Fluid material may be introduced into the tank in any desired manner, by any desired means, not here shown.

Where a central partition like the member 4 is used, a scum trough 6 is installed upon or in it. As shown the trough is made so that its upper 20 edges 7 are above the surface of the fluid within the tank and on each side the scum trough is provided with an inclined surface 8 which slopes upwardly from a point below the surface of the liquid to the upper edge of the scum trough above 25 the surface of the liquid. A pipe 9 or other means for withdrawing the scum from the trough may be provided. Whatever the shape of the scum trough and whatever means are provided for removing scum from the trough, the trough will 30 ordinarily have its upper edges above the surface of the fluid so that material will not enter the trough except when positively moved by some collecting or skimming means.

The scum collecting means comprises, 'in the 35 form shown, two collecting assemblies which are ' substantially alike. Each collector assembly thus comprises a truck formed of side members 10 and cross members ί i. Axles 12 are journaled in the side members and carry preferably flanged rollers 40 ί 3 which engage and run upon tracks 14 mounted adjacent the tank and preferably along the upper edges of the side walls 3. Extending across between the transverse members II are frame members 15 and extending upwardly from the trans- 45 verse members 11 and preferably generaly above the members 15 are frame members 16. Journaled in suitable bearings supported by the members 16 is a shaft 17 carrying a sheave 18.

Journaled preferably in the side members 10 50 in bearings 19 is the collector shaft 20. Fixed on this shaft is a brake drum 21. Brake bands 22 contact the brake drum, are fastened at one end to a link or links23 and are yieldingly drawn towards each other at their other ends by a 55

2,159,409 spring 24. The effect of the brake and brake construction just described is to resist rotation of the shaft 20, but if sufficient force is applied the shaft may turn.

S Secured to the shaft 20 are two downwardly depending arms 25. At their lower ends they carry a transverse skimmer or collector blade 26, which may carry a flexible wiper or squeegee 27.

To move the collector assembly along the tracks 14 a cable 28 is provided. It is fastened to one of the transverse members I ί by means of a ring bolt 29 or otherwise, and passes to a driving sheave 30, which by means of gearing 31 is driven from 15 a motor 32. The cable 28 passes over the sheave and back across the collecting assembly engaging the sheave 18. It passes thence about an idler sheave 33, supported in bearings 34 which are mounted upon a take-up 35. The cable 28 passes 20 thence from below the idler 33 to the second of the cross members t i to, which it is attached by means of a ring bolt 36 or otherwise.

Where, as in the form shown herewith, there is more than one collector assembly, the cable is 2S attached at one end to each of them, passes over the idler sheave on the top of each and a connecting cable 37 is provided between the two assemblies to attach them together. Whether one or more conveyors are used, they are driven by .30 the cable 28 and move back and forth as it moves.

In the particular form of the invention shown there are two collector assemblies, both driven by the same cable and connected to each other by the cable 37. The collector assemblies comprise M the same general parts and may not differ from each other at all. For some purposes it is convenient, however, to pivot the shaft 20 which carries the members 25 toward different ends of the truck which carries them. Thus in the left 40 hand collector assembly the shaft 20 is pivoted adjacent the right hand as shown in Figure 1, while in the right hand collector assembly the shaft 20 is pivoted adjacent the left end. The reason for this is that as the assemblies, move 45 back and forth the members 25 contact the end walls of the tank or chamber and it Is preferable to have the member which contacts the wall face or curve slightly away from it as indicated in detail in Figure 4 and generally in Figure 1. It '50 is convenient also to provide cams 38 on the inner faces of the end walls, one to be contacted by each of the members 25 and thus the members 25 and the shafts Which carry them are assembled at the appropriate ends of the trucks and are faced 55 with respect to the end walls of the tank so that the blades 26 and 27 do not strike the end walls when the conveyors are in the extreme end position as shown in detail in Figure 4.

Each of the members 25 may have an extension 00 39 which is in effect a continuation of the member 25 and upon the member 39 a movable counterweight 40 may be mounted. For some purposes this is not necessary and for some purposes only one of each pair of members 25 will 55 carry the extension 39 and the counterweight. The use of the counterweight will be explained below.

Mounted above the partition wall 4, preferably centrally above the scum trough 6, as shown in 70 Figures 3 and 5, is a cross-bar 41 adapted to be contacted by the skimming arms 25 as will be described below.

It has been pointed out above that the collector assembly is caused to reciprocate, moving first ' in one direction and then another along the tanks; while any reversing means may be arranged and while the invention is not limited to any particular reversing means, the form shown comprises electric limit switches 42 and 43, as shown in Figures 1 arid 4, which may be mounted g upon suitable brackets 44 to one of the side walls 3. The limit switches are actuated by a contact cam member 45 carried by the truck of one of the collector assemblies, herein illustrated as secured to the collector assembly adjacent the driv- ₁₀ing sheave 30.

The brackets 44 may also support overtravel limit switches 46 and 47 respectively, which may be actuated by the cam member 45 if either of the limit switches 42 and 43 fail to reverse the motor ₁₅32. The overtravel limit switches 46 and 47 serve to break the electrical circuit through the motor 32 and stops movement of the collecting assemblies.

Limit switches might, of course, be mounted ₂q anywhere else to contact any other moving part of the apparatus. When they are moved the limit switches cause reversal of the motor and hence reversal of movement of the collecting assemblies.

There is shown in Figures 6, 7 and 8 an assem- _2gbly of sewage treatment tanks into which material is discharged for treatment, in which settling takes place. Means are shown for moving the scum to one end of several tanks and for moving the sludge to the opposite end of the tanks, and ₃θ cross collectors are shown for collecting the sludge so moved and moving it to discharge hoppers, and a cross collector or skimmer such as that shown in Figures 1 to 5, inclusive, in detail, is shown generally in Figures 6 to 8, inclusive. ₃₅As so shown the scimi collector or skimmer is arranged to Collect the scum from a plurality of tanks and to discharge it to a, jingle point of discharge. As thus shown there: is a battery of tanks in which material is treated and through 40 which material is conveyed to points of collection where Cross collectors, operating through several tanks and divisions of tanks, collect in one place the scum and in another place the sludge for removal from the tanks. 45

As shown in Figure 6 there are assembled in one installation a plurality of tanks 48. Fluid material is brought to these tanks for treatment from an influent conduit 49 and is discharged into the various tanks or divisions of the tanks for ₅₀treatment through ports 50 controlled by valves 51 which may be operated by valve moving mechanisms 52. The various tanks 48 may be divided with partitions 53 which extend partly upward from the bottom of the tanks but do not 55 divide the tanks throughout their total height. Extending laterally across the tanks 48, preferably at their ends adjacent the Influent conduit, are a series of sludge collecting troughs 54 each of which terminates at one end in\a sludge hop- go per 55 from which sludge is removed \by any suitable means. 56 are effluent or settled sewage conduits.

Extending across each of the tanks 48 as indicated in detail in the first five figures, is a scum ₆₅collecting and discharging mechanism which has been described in detail in connection with the description of the first five figures and need not be described again herewith. Positioned within each of. the sludge collecting troughs is a 70 cross collector for moving sludge toward the sludge hopper 55. This comprises idling sprockets 56α, 56α, and a driven sprocket 57, chains 58 and flights 59 mounted upon them. These cross collectors are driven in the direction of the arrow 75

2,169,409 in Figure 8 and move sludge to the discharge hopper 58.

It will be noticed that a single sludge collector operates throughout the entire length of a tank 5 48 and collects and discharges into .the hopper the sludge from the whole tank, and that there are preferably three collectors formed of the chains 60 and flights 6( in each tank 48, separated from each other by the partitions 53. Similarly the 10 scum collector described above in connection With Figures 1 to 5, inclusive, collects the scum from an entire tank. However, in connection with the scum collector two collectors are mounted with a single drive to discharge scum 15 into a single sump, as illustrated in detail in Figures 1 and 3,

As a means for moving the sludge to the sludge cross collector and for simultaneously moving scum to the scum cross collector, there is posi2Q tioned in each of the tanks 48 a conveyor comprising chains 60 and flights 61 so arranged that the lower run of the conveyor carries sludge toward the sludge discharge and collecting mechanism while the upper run of the conveyor carries 25 scum toward the scum discharge mechanism. The direction of movement is indicated by the arrows in Figure 7. The chains 60 are positioned about idler sprockets 62, 62, supported in suitable bearings adjacent the bottom of the tank, and 30 idler sprockets 63, adjustably supported in adjustable bearings adjacent the upper surface of the liquid within the tank. 64 are driving sprockets on a shaft which carries a sprocket 65 and is driven by a chain 66 from a sprocket 61 35 driven by a motor 68 or by any other suitable power source.

As shown, the tanks are open or uncovered and only sufficient structural parts extend over the surface of the tanks to support the driving mech₄₀ anism and to support the scum cross conveyors.

The driving means for the various conveyors might be changed in many respects and the invention is not limited to the particular means for driving the main conveyors within the tanks nor ₄₅ to the particular means for driving the cross conveyors and the invention contemplates broadly the provision, in connection with a number of tanks, of means for conveying material along the bottom of the tanks and along the surface of the ₅₀ tanks and it further contemplates the association with such conveyors and such multiplicity of tanks of cross conveyors for handling the sludge on the bottom of the tank and for handling scum and other floating material on the top of the 55 tank, whereby a single cross conveyor handles, collects and conveys accumulations and discharge from several divisions of a single tank, or in some cases from a plurality of tanks.

The use and operation of the invention are as 60 follows:

Assume the parts in the position shown in Figure 1. The left hand assembly has been moved against the left hand end wall of the tank. The right hand assembly has been moved against ₆₅ the partition 4, has struck the inclined surface on the right of the scum trough and has moved up along it as indicated in the first dotted line position A to the full line position. In that position it has completed its skimming operation ₇0 and has discharged the scum into the scum trough and swept the right hand inclined surface 8 clear. It continues slightly farther, moving to the left, until it reaches the second dotted line position B. It has thus been moved from the first dotted line 75 position A which is the skimming position, and in which the lower portion of the blade 26 extends slightly below the water level and it has been tilted to a position in which it is clear of the water. Its tilting movement was resisted by the brake and counterweight assembly. 5

During the movement of the right hand assembly just described the left hand assembly has moved into contact with the left hand end wall I. The members 25 have contacted the cams or guides 38 and have been swung from the dotted 10 line position C, which they occupied in their movement to the left, and moved into the full line position shown at the left of Figure 1 generally and in detail in Figure 4. Thus the left hand skimmer blade 26 is slightly below the water level 15 while the right hand blade 26 is clear of the water surface. In the dotted line position B of the right hand assembly and full line position of the left hand assembly, the cam member 45 has contacted the limit switch 42 and caused re- 20 versal of movement. As the assemblies now move in the reverse or right hand direction the left hand blade 26 collects the scum and moves it toward the scum trough. At the same time the right hand blade 26 moves to the right but it is 25 above the water and hence clears the water and the scum. It remains in that position until it strikes the right hand end wall of the tank and is swung downward into contact with the water again. As this is occurring the left hand col- 30 lecting assemlily has moved the scum to the left hand side of the scum trough, has carried it up the left hand inclined surface 8 and deposited it in the scum trough. It continues its movement slightly farther until the cam member 45 contacts 35 the limit switch 43 and the movement of the parts is again reversed.

Thus as the two collecting assemblies continue to reciprocate, first one skims half of the tank, as it moves , toward the scum trough, and the 40 other assembly moving in the same direction, rides above the water until it strikes its end wall and is moved into the downward position. Thus each section of the tank is skimmed alternately and the collecting assemblies move back and 45 forth, skimming in one direction, as they move toward the scum trough, and riding clear of the water in the reverse direction as they move away from the scum trough. Note that the cross bar 41 serves to rotate the members 25 to their 50 final position, for example, to the position B, of the right hand assembly in Figure 3, in which they are held by the brake members 21 and 22.

The operation of the total installation as shown for example in one form in Figures 6, 7 and 8, 55 will now be described. Fluid material for treatment is conveyed into the main influent conduit and is admitted to the various tanks as desired. Material remains in the tanks for a period necessary to accomplish the settlement of sludge to- 60 ward or upon the bottom of the tank. During this period also scum and floating materials of various sorts collect upon or near the surface. During this period while the scum is collecting on the surface and the sludge is collecting at 65 the bottom, the main conveyors which run longitudinally through the tanks move slowly to carry the sludge toward one end of the tank into the sludge cross troughs and carry the scu preferably to the opposite ends of the tanks. When 70 --, sufficient sludge and scum have accumulated at or near the ends of the tanks the cross conveyors are set in operation and the scum and sludge are moved crosswise of the longitudinally extended tanks arid are collected and discharged. Fre- 75

2,158,400 quently in operation all of the conveyors will be operating simultaneously, but this is not essential and at times one or another of the conveyors may be stationary while one or more of them is 5 in motion. While in the assembly shown the tanks are in alignment with each other this need not be the case and for some installations the tanks will be slightly out of alignment, but whatever the relative position of the tanks with re10 spect to each other, means are provided for discharging influent into the tanks, conveying means are provided for moving sludge and scum along the tanks and cross conveying means are provided for collecting the sludge and scum and πιόνι 5 ing them to suitable discharges.