A screen decanter for decanting liquid from a reservoir, comprising at least one rack comprising screens and baffles forming the sides of a cavity; a frame attached to the screens and baffles and providing a barrier so that liquid cannot pass from outside into the cavity without passing through the screens; a patterned perforated drain pipe inside the cavity and leading to an opening through which liquids may drain out from the cavity. The pattern of the openings counteracts the hydrostatic head within the rack such that flow through the screens is uniform at all depths of immersion in the liquid reservoir. Preferably, the screens have a porosity of about 50 micrometers.

An overflow system for a hopper dredger comprises an overflow tube; an inlet for taking in head water from the hopper; and a collector to collect the flow of head water entering the inlet and guide the flow to the overflow tube. The collector comprises a substantially horizontal top portion which delineates a top of a flowpath for head water into the collector to ensure substantially radial flow into the collector. At least one of the overflow tube and the inlet is adjustable for controlling flow into the overflow system.

Apparatus for clarifying a sludge-containing effluent, comprising a clarification basin (2), at least one arm (7) able to move over the upper surface of the liquid in the basin; at least one trough (8) supported by the arm so that it can be immersed over part of its height in the liquid of the basin, suction tubes (T1, T2) held relative to the trough, each tube comprising at the top a vertically adjustable sleeve (B1, B2) opening into the trough, and a means of removing sludge from the trough; the sleeve (B1, B2) of at least one suction tube (T1, T2) is free to slide vertically relative to the mobile arm (7) supporting the trough, and to the tube (T1, T2) and a reserve of buoyancy necessary and sufficient for keeping the overspill end (E1, E2) of the sleeve in the trough (8) continuously out of the water is installed on the sleeve (B1, B2) so that the overspill level of the sleeve adjusts automatically in relation to the level (16) of liquid and sludge in the trough.

A screen decanter for decanting liquid from a reservoir, comprising at least one rack comprising screens and baffles forming the sides of a cavity; a frame attached to the screens and baffles and providing a barrier so that liquid cannot pass from outside into the cavity without passing through the screens; a patterned perforated drain pipe inside the cavity and leading to an opening through which liquids may drain out from the cavity. The pattern of the openings counteracts the hydrostatic head within the rack such that flow through the screens is uniform at all depths of immersion in the liquid reservoir. Preferably, the screens have a porosity of about 50 micrometers.

The present disclosure relates to a biofilter for wastewater digestion, in which a high degree of contaminant removal is obtained with a single device. In order for these levels to be achieved, the following are essential: the shape of the biofilter, the supply/discharge ratio of the biofilter, the position and height of each of the components and, finally, the combination of two packed zones, namely: a random zone, and a zone arranged in the form of ringed or corrugated tube bundles.

In a method for fabricating a separation fence (1) to be used in a hydrometallurgical liquid-liquid solvent extraction settler, the fence is manufactured of polymer resin. The fence (1) is manufactured as a shell-like integral piece by rotational molding. The fence (1) is a rotationally molded shell-like integral piece.

An extrusion system for separating soil entrained in wash water, e.g. from harvesting tuberous produce, includes a settling tank configured to receive a flow of soiled water, to allow soil to settle by gravity, and to allow clarified water collection at the top. A diffuser suspended within the tank converts the flow of soiled water into multiple transverse flows to avoid churning the settled soil. A sensor detects the level of settled soil reaching a predetermined setpoint, and in response the system actuates an auger and opens a pinch valve to force concentrated soil from the bottom of the settling tank.

A liquid treatment unit removes particulate matter and colloids from a liquid, as found in waste water on mines, on construction sites and on heavy industry sites. The liquid treatment unit includes an electrocoagulation unit and a cyclonic separator unit. The liquid to be treated is first subject to electrocoagulation and then fed into the cyclonic separator unit. The cyclonic separator unit guides the electrocoagulated liquid in a circular path downwardly from an outer perimeter to move underneath a skirt and then upwardly and inwardly towards a central outlet located at the top of the cyclonic separator. Floating particles are skimmed from the surface outside of the skirt. In moving to the outlet, the liquid passes through a plurality of nested frusto-conical guide members. An ultrasonic transducer is used to collapse bubbles formed by electrocoagulation, and to clean the electrocoagulation electrodes.

A floating liquid intake for a liquid suction removal system, the liquid intake comprising housing defining an internal cavity. The housing has a hollow and buoyant annular body, an upper cover and a lower cover. The internal cavity is formed between the upper and lower covers. A substantially annular inlet is formed in the annular body for ingress of liquid into the cavity. The annular body has a buoyancy sufficient for the liquid intake to float in a liquid with the annular inlet submerged below the surface of the liquid in which the liquid intake is floating. A pipe extends into the cavity and the pipe includes an inlet that in use is open below the surface of the liquid within the cavity. The pipe extends outside of the cavity for connection to a liquid suction removal system.

A single stage clarifier mixing assembly includes a housing having a circular sidewall and a center axis, a mixing section in the housing, a clarifier section overlying and axially aligned with the mixing section along the center axis within the housing, an inlet delivering an inlet stream to the mixing section and an agitator. The agitator is adapted for mixing the inlet stream in the mixing chamber.