Back to results
US 11,891,323 B2Granted
Salt separation and destruction of PFAS utilizing reverse osmosis and salt separation
AssigneeRevive Environmental Technology, LLC
InventorsStephen H. Rosansky, Michael Miller, Patrick Norris, Darwin Argumedo, Douglas Hendry, Ian Haggerty, Keith Brown, Joshua James, Joseph Casciano, Slawomir Winecki, Vivek Lal, Tom McGuinness
Life of this patent
Estimating the term…
Abstract
Per- and polyfluoroalkyl substances (PFAS) are destroyed by oxidation in supercritical conditions. PFAS in water is concentrated in a reverse osmosis step and salt from the resulting solution is removed in supercritical conditions prior to destruction of PFAS in supercritical conditions.
Claims19
A method of destroying PFAS, comprising:
- providing an aqueous solution comprising water and PFAS;
- subjecting the aqueous solution to reverse osmosis to produce a clean water fraction and a briny concentrated fraction in which the PFAS concentration is at least 50% greater than the aqueous solution;
- preheating the briny concentrated fraction in a heat exchanger to form a preheated concentrated fraction that is at subcritical conditions;
- passing the preheated concentrated fraction into a pre-reactor where the briny concentrated fraction is converted to supercritical conditions at a first temperature causing sodium chloride to precipitate;
- removing at least a portion of the sodium chloride to produce a brine-reduced fraction;
- passing the brine-reduced fraction to a reactor where the fraction is subjected to oxidation under supercritical conditions wherein the concentration of oxidant and/or temperature is higher than in the pre-reactor;
- producing a clean hot water solution having a concentration of PFAS that is at least 90% less than the aqueous solution;
- and, wherein a fuel or oxidizer is added to the pre-reactor;
- and further comprising transferring heat from the clean hot water solution to the aqueous solution in the heat exchanger in the preheating step.
6 more elements
A method of destroying PFAS, comprising:
- providing an aqueous solution comprising water and PFAS;
- treating the aqueous solution to reduce its volume to form a reduced volume PFAS solution having a first concentration of PFAS;
- adding hydrogen peroxide to the reduced volume PFAS solution wherein the hydrogen peroxide is added in excess of that needed to destroy the PFAS;
- passing the reduced volume PFAS solution into a SCWO reactor and subjecting the reduced volume PFAS solution to supercritical water oxidation;
- and
- producing a clean effluent having a concentration of PFAS that is more than 100,000 times less than the first concentration of PFAS:
- and
- wherein flow through the SCWO reactor is turbulent flow with an Re of at least 2000.
5 more elements
A method of destroying PFAS, comprising:
- providing an aqueous solution comprising water and PFAS;
- treating the aqueous solution to reduce its volume to form a reduced volume PFAS solution having a first concentration of PFAS;
- adding hydrogen peroxide to the reduced volume PFAS solution wherein the hydrogen peroxide is added in excess of that needed to destroy the PFAS;
- passing the reduced volume PFAS solution into a SCWO reactor and subjecting the reduced volume PFAS solution to supercritical water oxidation;
- and
- producing a clean effluent having a concentration of PFAS that is more than 100,000 times less than the first concentration of PFAS;
- and wherein the reduced volume PFAS solution is mixed with a solution comprising 30 to 50 wt % H2O2 at a weight ratio of between 30:1 and 70:1 wt % PFAS solution.
4 more elements
A method of destroying PFAS, comprising:
- providing an aqueous solution comprising water and PFAS;
- treating the aqueous solution to reduce its volume to form a reduced volume PFAS solution having a first concentration of PFAS;
- adding hydrogen peroxide to the reduced volume PFAS solution wherein the hydrogen peroxide is added in excess of that needed to destroy the PFAS;
- passing the reduced volume PFAS solution into a SCWO reactor and subjecting the reduced volume PFAS solution to supercritical water oxidation;
- and
- producing a clean effluent having a concentration of PFAS that is more than 100,000 times less than the first concentration of PFAS;
- and wherein the SCWO reactor comprises a flow channel having an internal diameter of at least 1 cm that slopes downward with respect to gravity.
4 more elements
Dependencies are inferred from the claim text.