Abstract: In a method of anaerobic treatment of an organic waste stream (1), a stream originating from an anaerobic reactor (5) is fed to a first separating unit (33) to be separated into a sludge fraction (7?) containing between 50% and 80% of the solids by weight and a second fraction (7). The second fraction (7) is fed from the first separating unit (33) into a Dissolved Gas Floatation (DGF) unit (16). The sludge fractions (7?) and (9) from the separator units (33) and (16) are fed back to an inlet 41 of the reactor 5.

Abstract: The present invention relates to a method of generating white water for use in Dissolved Air Flotation (DAF) processes, the method comprising the steps of forming a reduced pressure air/water mixture; subjecting the air/water mixture to an elevated hydrostatic pressure in a water column to achieve substantial dissolution of air in water; removing the air in water solution from the elevated hydrostatic pressure region to form a super-saturated air in water solution; and introducing the super-saturated air in water solution into a process stream wherein the air is released from solution as white water micro-bubbles while in intimate contact with contaminants to perform Dissolved Air Flotation.

Abstract: The invention relates to a method for treating fluid (2) resulting from hydraulic fracturing with liquid/solid separation (3), comprising the steps of: receiving the fluid in a vessel (4), such as a mixing tank or a plug flow reactor, adding a chemical mix comprising organoclay to the fluid in the vessel to reduce levels of dissolved salts and organic compounds and molecules, and to allow coagulation and flocculation to occur, adding pH-adjustment chemicals to the fluid in the vessel to reduce water hardness, adding a micaceous metal complexing agent to the fluid in the vessel to at least partially remove ionic or complexed metalloids. The invention also relates to an assembly for carrying out the method as well as a vessel to be used therein.