Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
  • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
  • B03B9/00—General arrangement of separating plant, e.g. flow sheets
  • B03B9/06—General arrangement of separating plant, e.g. flow sheets specially adapted for refuse
  • B03B9/061—General arrangement of separating plant, e.g. flow sheets specially adapted for refuse the refuse being industrial
  • B03B9/063—General arrangement of separating plant, e.g. flow sheets specially adapted for refuse the refuse being industrial the refuse being concrete slurry
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
  • B01D21/0015—Controlling the inclination of settling devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
  • B01D21/003—Sedimentation tanks provided with a plurality of compartments separated by a partition wall
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
  • B01D21/0039—Settling tanks provided with contact surfaces, e.g. baffles, particles
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
  • B01D21/02—Settling tanks with single outlets for the separated liquid
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
  • B01D—SEPARATION
  • B01D21/00—Separation of suspended solid particles from liquids by sedimentation
  • B01D21/24—Feed or discharge mechanisms for settling tanks
  • B01D21/2405—Feed mechanisms for settling tanks
  • B01D21/2416—Liquid distributors with a plurality of feed points
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B03—SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLID MATERIALS OR FLUIDS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS
  • B03B—SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATIC TABLES OR JIGS
  • B03B5/00—Washing granular, powdered or lumpy materials; Wet separating
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies
  • Y02W30/58—Construction or demolition [C&D] waste

Definitions

• This invention relates to apparatus for the batch reclamation of aggregate from waste plastic concrete.
• a certain amount of waste plastic concrete is generated at ready mixed and precast concrete plants.
• the cost of aggregates is increasing and in some parts of the U.K. they are in short supply.
• the object of this invention is to provide simple, relatively unsophisticated apparatus for removing cement and some aggregate fines from waste plastic concrete and to return the coarse aggregate (stone) and a large proportion of the fine aggregate (sand) to stock for reuse.
• apparatus for batch reclamation of aggregate from waste plastic concrete comprising a base, an open-topped container hinged to the base, means for moving the container relative to the base from a substantially level, working position to a tilted, discharging position, partitions in the container extending transversely to the hinge and dividing it into at least three tanks with the upper edges of the partitions providing weirs from a first tank to a second tank and so on, and means for introducing water under pressure downwards into said first tank, wherein, in use with the container in said working position, waste plastic concrete is deposited in said first tank and subjected to water under pressure, which causes cement and fine aggregate to be washed out of the concrete and separ- ated from coarse aggregate by being carried over a first weir for collection in said second tank, the latter overspilling a second weir into a third tank with cement particles and some aggregate fines in suspension, and wherein after such separation the contents of said first and second tanks are removed by tilting the container to said
• At least one drain outlet will conveniently b provided for discharging a slurry of cement and fines from the third tank, and this may go to a separator for further treatment.
• This could be a hydrocyclone or a settling tank/pit.
• Means will preferably be provided for preventing the separated fine and coarse aggregate from mixing during discharge from the container, and conveniently the discharge end of the container includes an aggregate stop, to allo surplus water to escape first.
• the container may b equipped with a hopper for loading the waste concrete into the washing tank and .at least one load cell may be provided between the container and its mounting.
• Each pipe may comprise an inner tube and an outer tube, the outer tube being provided with one or more air inlets, and the inner tube being connected to th water supply line.
• the pipes may be oscillated across the first tank to provid uniform washing, and they may be vertical or offset from th vertical.
• the second tank will be provided with agitating means to keep the very fine material in suspen ⁇ sion.
• Figure 1 is a perspective view of aggregate reclamation apparatus
• FIG. 1 is a diagrammatic plan view of the apparatus of Figure 1
• Figure 3 is a diagrammatic cross-section on the line III-III of Figure 2
• Figure 4 is a longitudinal section of a pipe forming part of the apparatus, Figure 5 shows the apparatus in its working condition;
• Figure 6 shows the apparatus in its discharging condition.
• the apparatus comprises a generally rectangular container 1 with an open top and a sloping end. It is provided with longitudinal partitions 2 and 3 which divide the container into a washing
• the bases of at least some of these tanks may be of shallow V or U-Section.
• the partition 2 slopes to make the top of the tank 4 wider than its base, and its upper edge is higher than that of the partition 3. These upper edges form weirs 7 and 8.
• Pipes 9 extend downwardly into the washing tank 4 and are supplied with water under pressure from a common supply line 10.
• a loading hopper 11 is provided in one side wall of the container 1 at about the mid-length of the washing tank 4, and drain outlets 12 are provided in the base of the drain tank 6.
• a paddle 13 extending virtually the length of the container is suspended into the settling tank 5 and can be oscillated transversely between the partitions 2 and 3.
• the upper edge of the partition 2 leads into a wedge-like formation 14 widening to the lip of that sloping end, and this is flanked by inwardly projecting stop ledges 15 extending to the sides of the con ⁇ tainer.
• the container 1 is pivotally mounted on a support base 16 by a transverse hinge 17 a short distance below the lip of the sloping end. Hydraulic actuators 18, symmetri ⁇ cally arranged one on each side, are coupled between the container 1 and its support base 16.
• One or more load cells are also provided between the container 1 and the support base 16 to control loading of waste concrete into the washing tank 4.
• Each pipe comprises an inner tube 19 arranged co-axially within an outer tube 20 extending down beyond the tube 19.
• the inner tube connects with the water supply line 10, and the outer tube has a number of air inlets 21 near its upper end.
• water under pressure is delivered from the line 10 into the inner tube 19. Its jet-like exit from the lower end of that tube causes air to be drawn into the air inlets 21 so that a mixture of water and air is discharged from the end of the outer tube 20 into the washing tank 4.
• the lower end of each pipe 9 extends below the level of weir 7, whilst the air inlets 21 are kept above the level of the weir and so above the .level of the liquid in the washing tank • 4.
• the pipes are preferably arranged to oscillate to and fro across the washing tank 4. More than one set of pipes may be used, and the pipes may be vertical or offset from the vertical.
• waste plastic concrete with a collapsed slump is loaded into the washing tank 4 via the hopper 11.
• the concrete in the washing tank 4 is subjected to the action of water, combined with air, from the pipes 9.
• Cement, sand and fine aggregate below about 5mm particle size are washed out of the concrete in the washing tank 4 and carried over the weir 7 into the settling tank 5, the coarse aggregate being retained in the washing tank 4.
• Sand particles are retained in the settling tank 5 whilst cement and fines are carried over the weir 8 into the drain tank 6, the paddle 13 keeping the contents agitated to ensure that the fine particulate material remains in suspension.
• a slurry of cement and fines is discharged from the drain tank 6, via the drain outlets 12, to a hydrocyclone or settlement pit or tank for eventual removal off site.
• the container 1 After completion of the washing process and emptying of the tank 6, the container 1 is tipped up from the Figure 5 to the Figure 6 position to discharge aggregate retained in the tanks 4 and 5. First, water will spill out and it will be allowed to run away to drain. At a certain angle, before all the water has escaped, the coarse and fine aggregate will start to slide, first towards the sloping end and then, as the angle increases, over that end towards the ledges 15. These form aggregate stops and temporarily halt the aggregates as the last of the "free" water pours away over them. But then, with the container 1 approaching the Figure 6 position, the aggregates will avalanche over the stop ledges 15 and over the lip of the sloping end.
• the coarse and fine aggregates from the tanks 4 and 5 are prevented from mixing together whilst being discharged by the wedge formation 14, which directs them to the side end regions 22 and 23 of the container.
• the container could have more, for more grad ⁇ uated separation.

Landscapes

• Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Separation Of Solids By Using Liquids Or Pneumatic Power (AREA)
• Processing Of Solid Wastes (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=10685979

Family Applications (1)

Country Status (4)

Families Citing this family (10)

Family Cites Families (13)

• 1990
  • 1990-11-26 GB GB9025651A patent/GB2249975A/en not_active Withdrawn
• 1991
  • 1991-11-25 WO PCT/GB1991/002082 patent/WO1992009369A1/en not_active Application Discontinuation
  • 1991-11-25 AU AU90300/91A patent/AU9030091A/en not_active Abandoned
  • 1991-11-25 EP EP91920588A patent/EP0558582A1/de not_active Withdrawn

Non-Patent Citations (1)

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