A method for treating process water of a flotation arrangement is disclosed. The process comprising the steps of a) dewatering overflow of a mineral flotation circuit in a gravitational solid-liquid separator to separate a sediment from a supernatant comprising water, silica-containing particles and soluble SiO2, fine particles, microbes, and residual flotation chemicals; b) subjecting the supernatant to cleaning flotation, in which at least 90% of the flotation gas bubbles have a size from 0.2 to 250 μm, in a cleaning flotation unit for collecting at least silica-containing particles, for separating at least silica-containing particles from the supernatant into cleaning flotation overflow, and for forming purified process water as cleaning flotation underflow; c) removing cleaning flotation overflow as tailings; and d) recirculating purified process water into the mineral flotation circuit. A process water treatment arrangement is also disclosed.

A method for separating a calcite-rich low-grade fluorite barite paragenic ore, includes the following steps: S1, crushing; S2, performing classification on a crushed ore to obtain a fine-grained ore, a medium-grained ore and a coarse-grained ore; S3, performing jigging gravity separation on the medium-grained ore and the coarse-grained ore to obtain first barite concentrates and jigging tailings; S4, performing color sorting on the jigging tailings to obtain calcite minerals and color sorting tailings; S5, combining the fine-grained ore and the color sorting tailings, and then performing ore grinding to obtain feeding materials in flotation; S6, performing flotation on the feeding materials in flotation to obtain fluorite concentrates and flotation tailings; S7, performing chute gravity separation on the flotation tailings to obtain second barite concentrates and chute tailings. The method achieves an effect of obtaining high-quality acid-grade fluorite concentrates (CaF.sub.2≥98%).

An above-ground low-energy method of dewatering highly contaminated waste e.g. leachate contaminated with at least a first group of contaminants and PFAS is described. The method comprises the step of removing the PFAS before removing the first group of contaminants. The removal of PFAS is undertaken by actively aerating the contaminated waste comprising PFAS to produce a waste stream comprising a concentration of PFAS and a liquid stream having at least some of the first group of contaminants. The one or more liquid streams are separated from the waste streams so as to dewater the contaminated waste. Optionally, the liquid streams are treated to remove the first group of contaminants.

Disclosed herein is a method for remediating sewage that contains persistent contaminants. The method comprises ozofractionating the sewage under conditions whereby a foam fractionate comprising persistent contaminants is produced and separated from an ozofractionated wastewater, quiescing the ozofractionated wastewater, whereby a residual ozone content of the ozofractionated wastewater is reduced, and contacting the quiesced ozofractionated wastewater with a microorganism population under conditions effective to biologically remediate the ozofractionated wastewater.

The present disclosure provides a method of recovering copper, molybdenum, and a precious metal value from a metal-bearing material, the method comprising bulk flotation of the metal-bearing material to form a flotation product, wherein the metal-bearing material comprises a copper compound, a molybdenum compound, and at least one precious metal value, pressure oxidizing the flotation product to form a pressure oxidized discharge, separating the pressure oxidized discharge to form a separated liquid and separated solid, extracting molybdenum, via a molybdenum solution extraction, from the separated liquid to form a molybdenum-containing stream and a copper-containing stream, extracting copper, via a copper solution extraction, from the copper-containing stream, and extracting the precious metal value, via a cyanide leaching process, from the separated solid.

A method of separating sludge which involves adding an insoluble mineral colloidal suspension into an industrial sludge to destabilize the industrial sludge and separating destabilized components of the industrial sludge. The insoluble mineral colloidal suspension includes magnesium hydroxide. In an alternative embodiment dry finely divided magnesium hydroxide can be added and then dispersed into an industrial sludge. Conventional flocculants and/or coagulants can also be added. Conventional physical separation processes can be used to separate the destabilized industrial sludge.

What is provided is a washing treatment system (1) for contaminated soil, including: a classifier (10) that is configured to obtain a sand fraction (S4) having a particle size within a predetermined range and a fine-grained fraction (S3) having a particle size smaller than the predetermined range, from contaminated soil (S0) containing one or more contaminants selected from dioxins and agricultural chemicals; a detaching/washing unit (20) that is configured to detach a contaminant particle containing the contaminant from a surface of the sand fraction (S4); a removal unit (30) that is configured to generate air bubbles in a presence of water containing a flotation chemical, allows the detached contaminant-bearing particles to attach to the air bubbles to form froth (F1), and removes the froth (F1) to obtain a first slurry (S6) containing primary purified soil; and an up-flow washing unit (40) that is provided downstream of the removal unit (30), and is configured to supply the first slurry (S6) into up-flow water (W2) to purify the primary purified soil.

A process is described for manufacturing white pigment containing products. The white pigment containing products are obtained from at least one white pigment and impurities containing material via froth flotation.

An above-ground low-energy method of dewatering highly contaminated waste e.g. leachate contaminated with at least a first group of contaminants and PFAS is described. The method comprises the step of removing the PFAS before removing the first group of contaminants. The removal of PFAS is undertaken by actively aerating the contaminated waste comprising PFAS to produce a waste stream comprising a concentration of PFAS and a liquid stream having at least some of the first group of contaminants. The one or more liquid streams are separated from the waste streams so as to dewater the contaminated waste. Optionally, the liquid streams are treated to remove the first group of contaminants.

Apparatus uses engineered collection media to recover mineral particles in a mineral extraction process, e.g., for processing a tailings stream at the end of a flotation separation process. The engineered collection media are added to slurry/tailings containing the mineral particles. The engineered collection media have collection surfaces coated with a chemical selected for attracting the mineral particles to the collection surfaces so the engineered collection media becomes mineral laden media in the slurry/tailings in a loading stage. The apparatus include three stages: removing unwanted material from mineral laden media; using a stripping agent to strip the mineral particles from the mineral laden media; and separating the engineered collection media from the mineral particles and the stripping agent. The stripping agent is reused for stripping, and the engineered collection media are returned to the loading stage. The engineered collection media can have a smooth or foam-like surface.