Abstract: There is provided a continuous stagewise flotation process comprising more than one stage of flotation with independent hydraulic control. The process comprises a first vessel for flotation configured to receive incoming liquid for treatment. The first vessel is associated with a first feed pump for hydraulically controlling the incoming liquid into the first vessel; and a first discharge pump for hydraulically controlling the discharge of first treated liquid from the first vessel. There is also a second vessel for flotation configured to receive incoming first treated liquid from the first discharge pump. The second vessel is associated with a second discharge pump for hydraulically controlling the discharge of second treated liquid from the second vessel.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.