A froth collection launder for a collection of froth from a mineral flotation includes a first and a second sidewall which are joined to form a bottom including a tip extending along the bottom, the first sidewall including a first end and the second sidewall including a second end at their open ends, at least one of the first and the second ends includes a froth overflow lip, and when the froth collection launder is positioned at its operation position a centre line is located in the middle of the first and the second end in the cross direction (x) of the froth collection launder. The tip is located between the centre line and one of the first and the second end in the cross direction (x) of the froth collection launder and the tip forms the lowest point of the froth collection launder.

The separator according to the invention comprises: a tank (1) for receiving waste material and containing fluid to separate waste material by density into floating and settled material; automatic feed means (18, 37), for example, a double screen (18) to feed waste material to the tank (1); motorised conveyor belts (3, 4) divided into a floating waste material conveyor (3) and a settled waste material conveyor (4) to extract floating or settled waste material from the tank (1): and a blower-type sorting device (21) comprising: a turbine (22) that provides an airflow; and a branched duct (23) divided into: a riser duct (26) to transport part of the airflow to a diffuser (39) beneath the automatic feed means (18, 37) to raise light-weight waste material; and a discharge duct (27) to transport and horizontally expel another part of the airflow in order to remove previously raised waste material. The separator according to the invention may incorporate bubble-making means, with injectors (2) to facilitate floatability and remove floating waste material.

A system for recovering fat, oil and grease (FOG) from wastewater has multiple annular flotation zones in a concentric configuration surrounding a central column to create progressively increasing surface areas for FOG and solid particles flotation, and thereby enhance FOG recovery and removal. Each flotation zone is equipped with an independent pressurized micro air and ozone bubbles distribution system. A controlled amount of ozone can be injected into the wastewater along with recirculated effluent and micro-size air bubbles. Upon the release of pressurized air-ozone-water mixture, micro-size bubbles are generated and distributed in each flotation zone to effectively float up FOG and solid particles in the wastewater stream.

A froth flotation arrangement and method for treating mineral ore particles suspended in slurry includes a flotation cell for separating the slurry into an underflow and an overflow and a primary line including at least three flotation cells connected in series, wherein each subsequent flotation cell is arranged to receive the underflow from the previous flotation cell, the flotation cell includes a tank and an impeller within the tank, and the flotation cell includes a gas supply within the tank, the tank includes a volume of at least 200 m3, the flotation cell including a froth collection launder capable to receive the overflow the froth collection launder including a froth overflow lip, the flotation cell having an available froth surface area (A froth), the flotation cell having a pulp area (A pulp), where the pulp area (A pulp) is calculated as an average from the cross sectional areas of the tank at the height (h1) of the impeller. A ratio between a height (h) from a bottom of the tank to the froth overflow lip of the froth collection launder and the diameter (D) of the tank at the height (h1) of the impeller (h/D) is less than 1.5.

A sparger device for sparging fluid into a slurry tank includes a hollow elongated body having a nozzle opening for sparging a sparging fluid flow to a slurry tank. The device further includes a needle for opening and closing the nozzle opening, and a control device being arranged to actuate the needle. The control device includes a control chamber partitioned into a first portion and second portion such that a pressure differential between the first portion and the second portion, closes or opens the nozzle opening and prevents slurry backflow from the slurry tank. The second portion may be provided with a control fluid pressure preventing slurry. A flotation apparatus and a flotation system in with such a sparger device are also discussed.

Liquid treatment apparatus comprises at least two chambers being first and second chambers through which a fluid can flow. The two chambers are separated by at least one choke nozzle which has an entrance in the first chamber and an exit in the second chamber. The choke nozzle comprises a converging section at its entrance, a throat section, a backward-facing step immediately after the throat section, and an exit section at its exit wherein the exit section diverges from the step. Similarly constructed mixing nozzles may be included in the apparatus. The apparatus is especially useful in processes requiring a gas to be entrained in a fluid so that the gas is in the form of very small bubbles that do not tend to coalesce and flash off such as in the dissolution of gold and other precious metals from ore and in the removal of arsenic from an ore.

Coarse particle flotation equipment and method based on coupled fluidization of cyclone and damping are provided. The flotation equipment includes a flotation column. A raw ore feed pipe is provided in an upper part of the flotation column. The flotation column is sequentially divided into a mine tailing bottom launder area, a cyclone mineralization area and a static separation area from bottom to top. A plurality of water-gas mixing jet pipes which are obliquely arranged inwardly and upwardly and communicated with an inner cavity of the flotation column being provided at a side wall of the cyclone mineralization area, jet directions of the plurality of water-gas mixing jet pipes are distributed clockwise or anticlockwise around an axis of the flotation column, and a damping element for reducing turbulence of a water flow is further provided between the cyclone mineralization area and the static separation area.

Disclosed is high-ash fine coal slime separation equipment and method, applicable to the field of coal washing. The high-ash fine coal slime separation equipment includes a feeding system (1), a mineralization system (2), a separation system (3) and a pulsating water flow control system (4). A coal slime mineralization region is isolated from a separation region; and a damping block and a pulsating water flow device are arranged in a mineral separation system. A flotation feeding is fed into the feeding system (1), slurry mixing operation is completed, coal slime enters the mineralization system after pulp mixing to generate turbulent collision to form mineralized bubbles, the mineralized bubbles enters the separation system (3) after passing through a turbulent-flow dissipation pipe (12), and meanwhile, pulsating water flow with a certain frequency and waveform is fed into the separation system (3) by the pulsating water flow control system (4).

A multi-stage float sorting device includes a first flotator float-sorting ores mixed with water based on a difference in density, and a second flotator provided with a column extending in a top-down direction, one side of which communicates with the first flotator to receive primary concentrates, and float-sorts the primary concentrates based on a difference in density to obtain secondary concentrates. The second flotator includes a washing water jetting section provided at a top of the column to jet washing water, a gas sparger provided at a bottom of the column to jet an inert gas, and an opening and closing section located between the washing water jetting section and the gas sparger to partition an inside of the column into upper and lower regions, and form an opening for rising secondary concentrates in the column according to a pressure state of the lower region.

Liquid treatment apparatus comprises at least two chambers being first and second chambers through which a fluid can flow. The two chambers are separated by at least one choke nozzle which has an entrance in the first chamber and an exit in the second chamber. The choke nozzle (1) comprises a converging section at its entrance (3), a throat section (4), a backward-facing step (5) immediately after the throat section (4), and an exit section at its exit (6) wherein the exit section (6) diverges from the step (5). Similarly constructed mixing nozzles (1) may be included in the apparatus. The apparatus is especially useful in processes requiring a gas to be entrained in a fluid so that the gas is in the form of very small bubbles that do not tend to coalesce and flash off such as in the dissolution of gold and other precious metals from ore in the removal of arsenic from an ore.