Abstract: An apparatus for processing aggregate material includes a chassis, a trough mounted on the chassis at an inclined angle, and at least one shaft rotatably mounted within the trough and extending from a lower to an upper end of the trough. The at least one shaft has blades mounted thereon, the blades being angled so that they carry material within the trough towards the upper end of the trough when the at least one shaft is in a normal direction of rotation. A discharge opening is formed in a base of the trough adjacent the upper end of the trough, a weir being provided in the trough upstream of the discharge opening over which processed material must pass to reach the discharge opening.

Abstract: An apparatus for reducing the water content of waste water sludge includes a column for receiving waste water sludge, an outlet at a lower end of the column, a first closure for closing the outlet of the column, a controller for controlling the opening and closing of the closure. The controller is adapted to open and close the first closure to periodically discharge amounts of settled fines from the lower end of the column. A water outlet is adapted to receive water overflowing from an upper end of the column.

Abstract: A method and apparatus for washing and grading sand includes a first grading screen adapted to separate a feed material into a fine fraction and a coarse fraction, the coarse fraction having a greater particle size than the fine fraction. A first fines separation stage including one or more hydrocyclones is adapted to receive the fine fraction entrained in water, downstream of the first grading screen to thereby remove fine contaminants. A first dewatering screen includes a deck adapted to dewater the fine fraction downstream of the first fines separation stage to provide a fine sand product, and a second dewatering screen includes a deck adapted to dewater the coarse fraction downstream of the first grading screen to provide a coarse sand product.

Abstract: A slurry handling apparatus includes at least one reception hopper includes a base, a rear wall and opposing side walls, and an opening provided in the base. Slurry delivered into the reception hopper from a tanker can pass through the opening in the base, and a respective first dewatering screen having an apertured screening deck is located beneath the at least one reception hopper so that slurry passing through the opening is delivered onto the deck of the respective screen, with undersize material and water passing through the apertures of the deck to be received within a sump, and with oversize material passing over the deck to be discharged from a downstream end of the deck.

Abstract: A method of grading and washing sand including the steps of removing oversize material from a feed material to which water is added on a first grading screen, whereby the oversize material passes over a downstream end of an apertured deck of the first grading screen, undersize material and water passing through the apertured deck being collected in a sump of the first grading screen before being passed onto an apertured deck of a second grading screen having apertures of a smaller size than those of the deck of the first grading screen, oversize material passing over a downstream end of the second grading screen, pumping water and undersize material from a sump of the second grading screen to a washing stage to remove fine contaminants therefrom.

Abstract: An apparatus for washing and grading sand includes a first vibrating screen having a deck arranged to receive a feed material. Oversize material passes over the deck of the first vibrating screen for collection as a first product, and undersize material and water are collected in a sump of the first vibrating screen before being pumped to a hydrocyclone. A second vibrating screen receives an underflow from the hydrocyclone upon a deck thereof, with oversize material passing over the deck of the second vibrating screen for collection as a second product. An overflow from the hydrocyclone passes into a settling tank, and a water storage reservoir receives water overflowing from the settling tank while sludge is collected and removed from a lower end of the settling tank. Water is passed from the water storage reservoir to the first and second vibrating screens to wash and fluidise material thereon.

Abstract: An apparatus for washing and grading sand and aggregate includes an aggregate grading and washing screen with a plurality of vertically stacked decks for producing a plurality of aggregate products therefrom, and at least one sump for collecting undersize material comprising sand and water from the plurality of decks. A plurality of sand washing and grading units each include a first hydrocyclone, a vibratory screen having a deck, and a sump beneath the deck for receiving undersize material and water passing through the deck. The deck of the vibratory screen receives an underflow from the first hydrocyclone. A further hydrocyclone receives undersize material and water from the vibratory screen's sump. Underflow from the further hydrocyclone is delivered onto the deck of the vibratory screen. The first hydrocyclone of each sand washing and grading unit receives undersize material and water from the sump of the aggregate washing and grading screen.

Abstract: A method of washing and grading silica sand for glass production includes removing trash and relatively large contaminants from a sand feed material via a sequence of multiple vibrating screens, collection sumps, hydrocyclones, a density separator, a classification tank, and a dewatering screen. The resulting silica sand product is suitable for glass production.

Abstract: An apparatus for the wet attrition of particulate material comprising an attrition scrubber; a dewatering screen comprising a deck and a sump beneath the deck, the dewatering screen being mounted upstream of the attrition scrubber whereby oversize material from a downstream end of the deck of the dewatering screen passes into the attrition scrubber; and a hydrocyclone wherein an underflow, containing a coarser fraction of the feed slurry, passes out of a lower outlet of the hydrocylone while an overflow, containing a finer fraction of the feed slurry and most of the water, passes out of an outlet at the upper end of the hydrocyclone, a pump being provided for pumping material from the sump of the dewatering screen to the inlet of the hydrocyclone, wherein the underflow from the hydrocyclone is passed into the attrition scrubber.

Abstract: An apparatus for washing and grading sand and aggregate includes a first multi-deck screen and a sump for collecting undersize material from the plurality of decks. A first set of hydrocyclones receives undersize material and water from the sump of the first screen. A second screen has a deck for producing at least one sand product and a sump beneath the deck, the deck of the second screen receiving an underflow from each cyclone of the first set of hydrocyclones. A second set of hydrocyclones receives undersize material and water from the sump of the second vibratory screen. The deck of a third screen receives an underflow from each cyclone of the second set of hydrocyclones. A further hydrocyclone receives undersize material and water from the sump of the third screen, and an underflow from the further hydrocyclone is delivered onto the deck of the third screen.

Abstract: An apparatus for washing and grading sand and aggregate includes an aggregate grading and washing screen with a plurality of vertically stacked decks for producing a plurality of aggregate products therefrom, and at least one sump for collecting undersize material comprising sand and water from the plurality of decks. A plurality of sand washing and grading units each include a first hydrocyclone, a vibratory screen having a deck, and a sump beneath the deck for receiving undersize material and water passing through the deck. The deck of the vibratory screen receives an underflow from the first hydrocyclone. A further hydrocyclone receives undersize material and water from the vibratory screen's sump. Underflow from the further hydrocyclone is delivered onto the deck of the vibratory screen. The first hydrocyclone of each sand washing and grading unit receives undersize material and water from the sump of the aggregate washing and grading screen.

Abstract: An apparatus for washing and grading aggregate includes a chassis; a first grading screen mounted on the chassis for removing oversize material from a feed material; a first hydrocyclone mounted on the chassis receiving undersize material and water from the first grading screen; a second grading screen mounted on the chassis for producing at least one sand product, the second grading screen receiving an underflow from the first hydrocyclone; a second hydrocyclone mounted on the chassis receiving undersize material and water from the second grading screen; and an underflow from the second hydrocyclone being delivered onto the second grading screen.

Abstract: A multi-deck screening assembly includes upper and lower screen decks, each having first and second deck sections. The upper deck's first deck section has first-size grading apertures, and its second deck section is downstream of the first deck section with second-size grading apertures larger than the first-size apertures. The lower deck's first section has third-size grading apertures and its second section is downstream of its first section with fourth-size grading apertures larger than the third-size apertures. A gap between the lower deck's first and second sections allows oversize material from the lower deck's first section to pass through to a first collection region. A diverter is positioned between the upper and lower decks and over the gap, whereby material from the upper deck collected on the diverter passes onto the lower deck's second section, thereby preventing undersize material that passes through the upper deck from passing directly through the gap.

Abstract: An apparatus for processing aggregate material comprising an inclined trough having a pair of shafts rotatably mounted therein, the shafts having staggered blades arranged pass between one another during rotation of the shafts and angled to carry material towards an upper end of the trough, excess water and any floating trash passing over a weir adjacent a lower end of the trough onto the deck of a first vibratory screen, and a second vibatory screen being mounted adjacent the upper end of the trough for receiving particulate material from the upper end of the trough, the second vibratory screen having at least one deck for grading the material, wherein water collected in a sump of the first vibratory screen is arranged to pass into a sump of the second vibratory screen.

Abstract: A process for refining sand for use as frac sand includes the steps of passing the sand through a first fines separation stage to remove fine particles of contaminant from the sand, reducing the water content of the sand (such as to less than 20%), passing the sand into an attrition scrubber unit containing moving blades to delaminate clay and other contaminants from the sand grains, passing the sand from the attrition scrubber unit through a second fines separation stage to separate fine contaminants from the sand, and dewatering the resulting sand product in a further dewatering stage.

Abstract: A process for refining sand for use as frac sand includes the steps of passing the sand through a first fines separation stage to remove fine particles of contaminant from the sand, reducing the water content of the sand (such as to less than 20%), passing the sand into an attrition scrubber unit containing moving blades to delaminate clay and other contaminants from the sand grains, passing the sand from the attrition scrubber unit through a second fines separation stage to separate fine contaminants from the sand, and dewatering the resulting sand product in a further dewatering stage.

Abstract: A multi-deck screening assembly includes a plurality of vertically-stacked downwardly-sloping screen decks, each with grading apertures through which under-sized material may pass, while over-sized material passes over a lower discharge end of each screen deck. The screen decks are mounted on a common frame, which is mounted on a chassis and provided with vibration device. The screen decks include an upper deck, an intermediate deck below for receiving under-sized material from the upper deck, and a lower deck below the intermediate deck for receiving under-sized material from the intermediate screen deck. A first chassis-mounted stockpile conveyor receives over-sized material from the lower deck, a second chassis-mounted stockpile conveyor receives over-sized material from the intermediate deck, and a third stockpile conveyor receives over-sized material from the upper deck.

Abstract: A screening apparatus for grading particulate material includes a grading screen having apertures for water and/or undersize particles to pass through. The grading screen is supported on a frame mounted on a chassis via resilient linkages, and the grading screen being vibrated by a vibrating device that imparts circular or reciprocating motion to the grading screen. The grading screen is set at a predetermined slope whereby material to be graded can be delivered onto an upper end while the grading screen is vibrated to convey the material over the grading screen and to cause undersize material to pass through the apertures. Oversize material is discharged from a lower end of the screen onto a conveyor or into a collection bay or hopper. A sump beneath the grading screen receives under-sized material passing through the grading screen, and a jet pump conveys material from the sump to a dewatering screen.

Abstract: A process for refining sand for use as frac sand includes the steps of passing the sand through a first fines separation stage to remove fine particles of contaminant from the sand, reducing the water content of the sand (such as to less than 20%), passing the sand into an attrition scrubber unit containing moving blades to delaminate clay and other contaminants from the sand grains, passing the sand from the attrition scrubber unit through a second fines separation stage to separate fine contaminants from the sand, and dewatering the resulting sand product in a further dewatering stage.