Title:
WATER SYSTEM IN MULTIPLE GROOVING OF PAVEMENT
United States Patent 3788704


Abstract:
Water used for cooling and lubricating cutting heads in multiple grooving of pavement is picked up in the form of a slurry containing dislodged particles of pavement material and cutter material and is recovered relatively free of such particulate material for reuse. The system provides first and second separation regions in which the slurry is concentrated progressively and maintains circulation between the first separation region and the slurrying region and between the respective separation regions.



Inventors:
STAAB D
Application Number:
05/289686
Publication Date:
01/29/1974
Filing Date:
09/15/1972
Assignee:
CARDINAL IND INC,US
Primary Class:
Other Classes:
299/39.2
International Classes:
E01C23/088; (IPC1-7): E01C23/09
Field of Search:
299/39-41,18
View Patent Images:



Primary Examiner:
Purser, Ernest R.
Attorney, Agent or Firm:
Morton, Jacobs Et Al C.
Parent Case Data:


This is a continuation-in-part of my copending patent applications, Ser. Nos. 212,253 and 212,475, both filed Dec. 27, 1971.
Claims:
The claimed invention

1. In multiple grooving of pavement, wherein water supplied to a multiplicity of laterally spaced cutting locations is slurried there with particles dislodged from the pavement being grooved and particles dislodged from cutting heads rotating in contact with the pavement thereat, a system of water recovery comprising picking up the slurry and passing it to a first separation region wherein the slurry is concentrated, passing the concentrated slurry to a second separation region wherein it is further concentrated, temporarily storing in a storage region the water from which it was further concentrated, gradually withdrawing water from the storage region and returning it to the first separation region, and withdrawing water from the first separation region for supplying to the cutting locations and for slurrying there with dislodged particles as aforesaid.

2. Water recovery in multiple grooving of pavement according to claim 1, wherein there is continuous circulation between the region of slurry formation and the first separation region and also between the storage region and the first separation region.

3. Water recovery in multiple grooving of pavement according to claim 1, wherein a plurality of stages of filtration are present in the first separation region.

4. Water recovery in multiple grooving of pavement according to claim 1, wherein at least one stage of settling is present in the second separation region.

5. Water recovery in multiple grooving of pavement according to claim 1, wherein water withdrawn from the storage region is directed laterally into the first separation region in the vicinity of slurry concentration therein.

6. System of water recovery in multiple grooving of pavement, comprising establishing separately a region for forming water supplied to the grooving location and particles dislodged thereat from pavement and from cutting heads rotating in grooving contact therewith into a slurry, a separation region into which the slurry is passed and wherein the slurry is concentrated and water is recovered therefrom, a settling region into which the concentrated slurry is passed and wherein it is concentrated further and more water is recovered therefrom, and a water storage region into which water is passed from the settling region; and providing flow of the slurry from the slurrying region into the separation region, flow of concentrated slurry from the separation region to the settling region, flow of water recovered in the settling region therefrom into the storage region and then back into the separation region, and flow of water from the separation region to the slurrying region.

7. Water recovery in multiple grooving of pavement according to claim 6, including removing the further concentrated slurry from the settling region.

8. Water recovery in multiple grooving of pavement according to claim 6, wherein the flow is continuous in a loop between the slurrying region and the separation region.

9. Water recovery in multiple grooving of pavement according to claim 6, wherein the flow is continuous in a loop from the separation region to the settling region on to the storage region and back to the separation region.

10. Water recovery in multiple grooving of pavement according to claim 9, wherein the flow is also continuous in a loop between the slurrying region and the separation region.

Description:
This invention relates to the use and reuse of water for cooling and lubricating cutting heads in multiple grooving of pavement, especially a system for circulation and recirculation of such water.

Multiple grooving of pavement to impart antiskid properties thereto is known, and the desirability of recovering and reusing water used in connection therewith is accepted. However, conventional water systems employed in pavement grooving are either so simple as to fail to provide sufficient water recovery or so complex as to be undependable in sustained operation.

A primary object of the present invention is provision of a simple but effective and dependable system of water recovery useful in multiple grooving of pavement.

Another object is plural passage through a separation stage in each complete cycle of water use.

A further object is use of stored recovered water to aid concentrated slurry removal during separation.

Other objects of the present invention, together with means and methods for attaining the various objects, will be apparent from the following description and the accompanying diagrams of a preferred embodiment, which is presented by way of example rather than limitation.

FIG. 1 is a schematic representation, partly similar to a rear sectional elevation and partly similar to a fragmentary plan, of components useful according to the present invention;

FIG. 2 is a schematic representation, partly similar to a side sectional elevation taken at II--II on FIG. 1, and with additional components useful according to the invention;

FIG. 3 is a schematic representation, partly similar to a side sectional elevation, of yet additional components; and

FIG. 4 is a block diagram illustrating interconnection of various steps in the practice of this invention.

In general, the objects of the present invention are accomplished, in multiple grooving of pavement, wherein water supplied to a multiplicity of laterally spaced cutting locations is slurried there with particles dislodged from the pavement being grooved and particles dislodged from cutting heads rotating in contact with the pavement: namely, by a system of water recovery comprising picking up the slurry and passing it to a first separation region wherein the slurry is concentrated, passing the concentrated slurry to a second separation region wherein it is further concentrated, temporarily storing in a storage region the water from which it was further concentrated, gradually withdrawing water from the storage region and returning it to the first separation region, and withdrawing water from the first separation region for supplying to the cutting locations and for slurrying there with dislodged particles as aforesaid. More particularly, this inventive process preferably provides continuous circulation between the region of slurry formation and the first separation region and also between the storage region and the first separation region.

FIGS. 1 and 2 show in their respective upper portions, in rather diagrammatic sectional elevation, from the rear and left side, respectively, apparatus components useful in the first separation region. Their lower portions show quite diagrammatically, in plan view and left side elevation, respectively, non-identical apparatus components useful in the vicinity of the slurrying region.

Separation tank assembly 10 includes tank housing 11, which has vertical walls, horizontal top wall 12, and bottom wall 13 sloping downward to the rear for most of its extent from minor horizontal portion 13a at the forward edge thereof to form sump 19. Cylindrical filter screen 16 depends from the central portion of the top wall throughout a major portion of the height of the tank front wall. Vent pipe 26 communicates with the interior of the tank via an opening into the tank top within the cylindrical screen and contains air exhaust pump P1. The air/liquid interface is indicated by a broken horizontal line from side to side.

Flanking cylindrical filter screen 16 are outer pair 14, 18 and inner pair 15, 17 of flat filter screens spaced from the sidewalls and from one another, as well as from the cylindrical screen, and extending from the front to the rear walls and from top wall 12 to the level of horizontal portion 13a of the bottom wall. Water outlet pipe 36 leads from the liquid within the cylindrical screen through the tank bottom wall to a plurality of spray outlet lines 37a to e (shown in plan in FIG. 1, in two gangs: 37a, c, e and 37b, d) provided with flow-control valves V. The left ones only (37a, b) in each gang appear in FIG. 2, in schematic side elevation.

Corresponding ganged cutter heads (only 32a, b being visible, in FIG. 2) in shrouds (33a, b visible) are located immediately ahead of the corresponding outlet lines to receive water spray therefrom to cool the cutter blades and to lubricate them in the grooves being formed thereby in underlying pavement (not shown). To the rear of the cutter heads are troughs (39a, 39b visible, FIG. 2), and respective slurry pipes 24 and 28 fitted with flow-control valves V' and leading into the top of tank housing 11 to discharge thereinto through respective outlets: 24a (FIG. 1) and 28a (FIGS. 1, 2), 28b (FIG. 2). Concentrated slurry discharge pipe 29, fitted with pump P2, leads from sump 19 at the bottom rear to outlet 29a in the top of settling compartment 41 of second separation tank assembly 40 (FIG. 3). Water supply pipe 38, fitted with pump P3, leads into the lower portion of first separation tank housing 11 and, together with branch 38' thereof at the left, discharges laterally thereinto from a plurality of outlets at each side, 38a, b through the right side wall (FIG. 2) and 38'a through the left side wall (FIG. 1) being visible.

FIG. 3 shows second separation tank assembly 40, which includes settling compartment 41, as already mentioned, and adjoining water storage compartment 43 separated by baffle 42. Opening 45 above midheight of the baffle interconnects the respective compartments. The bottom wall of the settling compartment slants downward to the rear and thereby forms sump 49, from which sludge discharge leads for removal of the further concentrated slurry or sludge that settles therein. Water supply pipe 38 exits from the storage compartment.

Operation of the described apparatus to practice the process of the present invention is readily understood, especially by further reference to the flow diagram in FIG. 4. A slurry of particles of dislodged pavement and cutting material is formed in water supplied to the grooving location to cool and lubricate the cutting heads, and much or most of such slurry is trapped in the troughs trailing the cutter heads. From the troughs the slurry is withdrawn through pipes 24 and 28 into the tank of FIGS. 1 and 2 in which a first separation step occurs. The resulting concentrated slurry is pumped through pipe 29 into the settling compartment of FIG. 3 in which a second separation occurs as the supernatant liquid passes through baffle opening 45 into the adjoining compartment for water storage. Disposal of further concentrated slurry or "sludge" is accomplished via outlet pipe 50 from the sump of the settling compartment. Water is withdrawn from the storage compartment via supply pipe 38 and is reinjected laterally into the first separation tank.

Two loops of circulation are apparent: (1) between the region of slurry formation (and pickup) and the region in which the first separation occurs, and (2) from that first separation region to the second separation region and to the water storage region and from there back to the first separation region. Circulation is preferably continuous in both loops so long as the grooving operation continues. The lateral reinjection of water into the first separation region aids withdrawal of concentrated slurry therefrom by inducing a centralized circulation thereof as distinguished from stagnation at the wall junctions. Of course, the preponderance of the recirculated water is filtered twice in the first region per circuit, instead of only once, before returning to the slurrying region. Other advantages and benefits of this invention will become apparent and accrue to the benefit of those undertaking to practice it.

Conventional materials of construction are satisfactory for construction, support, and interconnection of the various components. Selection of such materials and dimensioning of the components are well within the abilities of persons having ordinary skill in the art. Further details of multiple grooving apparatus with which this water recovery system may be used are set forth also in my aforementioned patent applications.

Although a preferred apparatus embodiment has been illustrated and described, modifications may be made therein, as by adding, combining, or subdividing parts or steps, or by substituting equivalents, while retaining significant advantages and benefits of the invention, which itself is defined in the following claims.