Concentrating of wastewater to reduce flow rate, cost, and footprint of treatment system

Patent metadata

Field	Value
Publication number	US-10125040-B2
Application number	US-201615347427-A
Country	US
Kind code	B2
Filing date	Nov 9, 2016
Priority date	Sep 24, 2010
Publication date	Nov 13, 2018
Grant date	Nov 13, 2018

Abstract

A system to remove contaminants from contaminated water contains a pre-concentrating subsystem, a contaminant removal subsystem or a biological subsystem configured to remove two or more contaminants, and a permeate blending subsystem. A process for removing contaminants from contaminated water includes concentrating contaminated water, treating concentrated contaminated water, and combining product water to produce environmentally acceptable product water.

First claim

What is claimed is:

1. A system to remove contaminants from a contaminated water, the system comprising:
a pre-concentrating subsystem configured to receive a volume of the contaminated water and produce a concentrated contaminated water having between about 10% and about 50% of the volume of the contaminated water and a first product water having between about 50% and about 90% of the volume of the contaminated water, the contaminated water having a first concentration of contaminants, and the concentrated contaminated water having a second concentration of contaminants at least two times higher than the first concentration of contaminants;
one of a contaminant removal subsystem configured to receive the concentrated contaminated water and a biological subsystem configured to receive the concentrated contaminated water,
wherein the contaminant removal subsystem comprises zero valent iron media disposed in a reactor, and is configured to remove contaminants selected from the group consisting of selenium-containing compounds, nitrate-containing compounds, arsenic-containing compounds, and mercury-containing compounds from the concentrated contaminated water, and configured to produce a second product water,
wherein the biological subsystem is configured to remove contaminants selected from the group consisting of selenium-containing compounds, nitrate-containing compounds, arsenic-containing compounds, and mercury-containing compounds from the concentrated contaminated water, and configured to produce second product water, and
the second product water having a third concentration of contaminants at least about 90% lower than the first concentration in the contaminated water and at least about 95% lower than the second concentration in the concentrated contaminated water; and

a permeate blending subsystem configured to receive the first product water from the pre-concentrating subsystem and all of the second product water from one of the contaminant removal subsystem and the biological subsystem to produce a blended product water having a fourth concentration of contaminants at least about 90% lower than the first concentration in the contaminated water by blending the first product water and the second product water.

2. The system of claim 1 , wherein the pre-concentrating subsystem comprises two pressure driven membrane systems fluidly connected in series.

3. The system of claim 1 , wherein the pre-concentrating subsystem comprises a filter system configured to remove macroparticles from the contaminated water.

4. The system of claim 1 , wherein the contaminant removal subsystem comprises a clarifier fluidly connected downstream of the reactor.

5. The system of claim 1 , wherein the zero valent iron media is disposed in one of a fluidized bed reactor, a packed bed reactor, or a mixed bed reactor in the contaminant removal subsystem.

6. The system of claim 1 , configured to produce the blended product water comprising less than about 5 ppb selenium-containing compounds.

7. The system of claim 1 , configured to produce the blended product water comprising less than about 4.4 ppm nitrate-containing compounds.

8. The system of claim 1 , configured to produce the blended product water comprising less than about 4 ppb arsenic-containing compounds.

9. The system of claim 1 , configured to produce the blended product water comprising less than about 24 ppt mercury-containing compounds.

10. The system of claim 1 , configured to produce the blended product water comprising less than about 24 ppm total dissolved solids.

11. The system of claim 1 , configured to produce the blended product water comprising less than about 5% of a concentration of selenium-containing compounds in the contaminated water.

12. The system of claim 1 , configured to produce the blended product water comprising less than about 15% of a concentration of nitrate-containing compounds in the contaminated water.

13. The system of claim 1 , configured to produce the blended product water comprising less than about 40% of a concentration of arsenic-containing compounds in the contaminated water.

14. The system of claim 1 , configured to produce the blended product water comprising less than about 5% of a concentration of mercury-containing compounds in the contaminated water.

15. A process for removing contaminants from a contaminated water, the process comprising:
concentrating the contaminated water to produce a first product water having a lower concentration of contaminants than the contaminated water, and a concentrated contaminated water having a concentration of contaminants at least two times higher than the contaminated water;
contacting the concentrated contaminated water with a zero valent iron media to produce a second product water having a concentration of contaminants at least 95% lower than the concentrated contaminated water, the contaminants selected from the group consisting of selenium-containing compounds, nitrate-containing compounds, arsenic-containing compounds, and mercury-containing compounds;
clarifying the second product water to produce a sludge comprising solid waste particles and a clarified liquid;
dewatering the sludge to produce a dewatered sludge and a dewatering liquid;
disposing of the dewatered sludge;
collecting the dewatering liquid; and
combining the first product water and all of the clarified liquid to produce a blended product water.

16. The process of claim 15 , further comprising thickening the sludge prior to dewatering the sludge.

17. The process of claim 15 , wherein concentrating the contaminated water comprises treating the contaminated water with a pressure driven membrane system.

18. The process of claim 15 , wherein concentrating the contaminated water comprises concentrating a volume of contaminated water and producing a first product water having about 50% to about 90% of the volume of the contaminated water and a concentrated contaminated water having about 10% to about 50% of the volume of the contaminated water.

19. The process of claim 15 , further comprising pre-filtering the contaminated water with a filter system to remove macroparticles, prior to concentrating the contaminated water.

20. A process for removing contaminants from a contaminated water, the process comprising:
concentrating the contaminated water to produce a first product water having a lower concentration of contaminants than the contaminated water, and a concentrated contaminated water having a concentration of contaminants at least two times higher than the contaminated water;
contacting the concentrated contaminated water with a biological subsystem to produce a second product water having a concentration of contaminants at least 95% lower than the concentrated contaminated water, the contaminants selected from the group consisting of selenium-containing compounds, nitrate-containing compounds, arsenic-containing compounds, and mercury-containing compounds;
clarifying the second product water to produce a sludge comprising solid waste particles and a clarified liquid;
dewatering the sludge to produce a dewatered sludge and a dewatering liquid;
disposing of the dewatered sludge;
collecting the dewatering liquid; and
combining the first product water and all of the clarified liquid to produce a blended product water.

Assignees

• Evoqua Water Tech Llc

Inventors

• Riffe Michael R
• Sassaman Frank L
• Wismer Michael W

Classifications

• C02F2101/20

  Heavy metals or heavy metal compounds · CPC title

• C02F1/385

  by centrifuging suspensions (centrifuges B04B) · CPC title

• C02F11/122

  using filter presses (C02F11/123 takes precedence) · CPC title

• C02F2101/163

  Nitrates · CPC title

• C02F3/30

  Aerobic and anaerobic processes · CPC title