US 11,878,924 B2
Process and device for anaerobic purification
Cornelia Theresia Maria Johanna Frijters, Hoorn (NL); and Sebastiaan Leonardo De Bruin, Balk (NL)
Assigned to PAQUES I.P.B.V., Balk (NL)
Filed by Paques I.P. B.V., Balk (NL)
Filed on Jun. 10, 2021, as Appl. No. 17/344,433.
Application 17/344,433 is a continuation of application No. PCT/EP2019/086595, filed on Dec. 20, 2019.
Claims priority of application No. 18215493 (EP), filed on Dec. 21, 2018.
Prior Publication US 2021/0331957 A1, Oct. 28, 2021
Int. Cl. C02F 3/28 (2023.01); C02F 1/38 (2023.01); C02F 11/04 (2006.01); C02F 1/24 (2023.01); C02F 103/32 (2006.01)
CPC C02F 3/2806 (2013.01) [C02F 1/38 (2013.01); C02F 3/286 (2013.01); C02F 3/2846 (2013.01); C02F 11/04 (2013.01); C02F 1/24 (2013.01); C02F 3/2893 (2013.01); C02F 2103/327 (2013.01); C02F 2209/03 (2013.01); Y02E 50/30 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A process for the separation of biomass from treated wastewater following anaerobic purification of wastewater, the process comprising:
(i) supplying a stream of wastewater comprising organic constituents to a reactor comprising biomass having anaerobic microorganisms;
(ii) mixing the wastewater and biomass to provide biogas and reactor contents comprising treated wastewater and biomass,
(iii) supplying at least a part of the reactor contents and a gas to a first tank, wherein the gas is injected at a pressure of at least 1.5 bar(a) to the first tank to pressurize the tank contents, and wherein the gas is dissolved in the tank contents,
(iv) supplying the pressurized tank contents to a second tank, wherein the pressure in the second tank is lower than in the first tank, to provide a floating biomass layer and a treated wastewater layer,
(v) withdrawing the treated wastewater from the second tank and recycling the biomass layer from the second tank to the reactor of (i).