Biologically active reactor system and method for treating wastewater

• US 7,022,233 B2
• Filed: 01/09/2004
• Issued: 04/04/2006
• Est. Priority Date: 11/07/2003
• Status: Expired due to Term

• Current Assignee: De Nora Water Technologies, Inc.
• Original Assignee: Severn Trent Services Water Purification Solutions Incorporated
• Inventors: Chen, Jeffrey J.
• Primary Examiner(s): Prince, Fred G.
• Application Number:
  US10/755,073
• Publication Number:
  US 20050150829A1
• Time in Patent Office: 816 Days
• Field of Search: 210/605, 210/621, 210615-618, 210/622, 210/150, 210/151, 210/903
• US Class Current: 210/605
• CPC Class Codes: C02F 1/001 Processes for the treatment of water whereby the filtration technique is of importance C02F1/44 takes precedence; construction of filters in general B01D24/00 - B01D41/00
• CPC Class Codes: C02F 3/06 using submerged filters
• CPC Class Codes: C02F 3/302 Nitrification and denitrification treatment C02F3/308 takes precedence
• CPC Class Codes: Y02W 10/10 Biological treatment of water, waste water, or sewage
• CPC Class Codes: Y10S 210/903 Nitrogenous

Abstract

A biologically active reactor system for the treatment of wastewater comprises one or more submerged denitrification reactors having coarse media particles and a fixed biological film comprising biologically anoxic active microorganisms. One or more submerged aerated filters are in fluid communication with the one or more submerged denitrification reactor, the submerged aerated filter comprising coarse media particles and a fixed biological film comprising biologically aerobic microorganisms for oxidation of organic matter. One or more deep bed denitrification filters for removal of suspended solids and denitrification of oxidized nitrogens are in fluid communication with the one or more submerged aerated filters, the deep bed denitrification filter comprising fine media particles of less than 6 mm. Effluent from the submerged aerated filter is recycled to the submerged denitrification reactor for pre-denitrification prior to being piped to the deep bed denitrification filter. During the method, wastewater influent along with treated effluent from the submerged aerated filter is fed to a submerged denitrification reactor.

Claims

1. A biologically active reactor system for the treatment of wastewater, the system comprising:

one or more submerged denitrification reactors, the reactors comprising upright walls defining at least one compartment and a floor, the compartment comprising a media bed, the media bed comprising coarse, uniformly sized mineral media particles and a fixed biological film comprising biologically anoxic active microorganisms;

one or more submerged aerated filters comprising biologically aerobic microorganisms for oxidation of organic matter in fluid communication with the submerged denitrification reactor;

the media bed of the submeraed denitrification reactor comprising media particles ranging in size from about 9 mm to 45 mm in diameter; and

one or more deep bed denitrification filters for removal of suspended solids and denitrification of oxidized nitrogens, the deep bed denitrification filter in fluid communication with the submerged aerated filter.

2. The biologically active reactor system of claim 1 wherein the media bed of the deep bed denitrification unit comprises fine media particles.

3. The biologically active reactor system of claim 2 wherein the size of the fine media particles comprises less than 6 mm.

4. The biologically active reactor system of claim 2 wherein the media bed comprises relatively uniform particles.

5. The biologically active reactor system of claim 1 further comprising a pre-treatment unit for receiving wastewater influent.

6. The biologically active reactor system of claim 5 further comprising piping from the deep bed denitrification filter back to the pretreatment unit to recycle dirty backwash from the deep bed denitrification filter to the wastewater influent entering the pre-treatment unit.

7. The biologically active reactor system of claim 5 further comprising piping from the submerged aerated filter to the wastewater influent entering the pre-treatment unit.

8. The biologically active reactor system of claim 1 further comprising piping from the submerged aerated filter back to the submerged denitrification reactor to recycle a portion of the wastewater effluent from the submerged aerated filter back to the submerged denitrification reactor.

9. The biologically active reactor system of claim 1 further comprising one or more clarification units positioned between the submerged aeration filter and the deep bed denitrification filter to reduce suspended solids in the wastewater effluent from the submerged aerated filter to the deep bed denitrification filter.

10. The biologically active reactor system of claim 9 further comprising piping between the one or more clarification units and the one or more submerged denitrification reactors for recycling the clarified effluent to the submerged denitrification reactor.

11. The biologically active reactor system of claim 9 further comprising one or more pre-treatment units and piping between clarification unit and the pre-treatment unit for recycling clarified effluent between the clarification unit and the pre-treatment unit.

12. The biologically active reactor system of claim 1 wherein the one or more deep bed denitrification filters comprise down flow filters.

13. The biologically active reactor system of claim 1 wherein the submerged denitrification reactor is an up flow filter.

14. The biologically active reactor system of claim 1 wherein the submerged denitrification reactor is a down flow filter.

15. The biologically active reactor system of claim 1 wherein the biologically active microorganisms comprise heterotrophic bacteria and autotrophic bacteria.

16. A method for submerged denitrification filtration comprising:

feeding a submerged denitrification reactor with wastewater influent, the reactor comprising one or more upright walls defining at least one compartment and a floor, the compartment comprising coarse, mineral media particles and a fixed biological film comprising biologically anoxic active microorganisms;

piping the effluent wastewater stream from the submerged denitrification reactor unit to a submerged aerated filter;

piping the remaining effluent from the submerged aerated filter to a deep bed denitrification filter for removal of suspended solids and denitrification; and

piping a portion of wastewater effluent from the submerged aerated filter to the wastewater influent entering a pre-treatment unit.

17. The method of claim 16 further comprising recycling a portion of the effluent stream from the submerged aerated filter back to the submerged denitrification reactor.

18. The method of claim 16 wherein the wastewater influent is pre-treated in a pretreatment unit prior to being piped to the submerged denitrification reactor.

19. The method of claim 18 wherein dirty backwash water from the deep bed denitrification filter is recycled to the pretreatment unit.

20. The method of claim 18 wherein effluent from the submerged aerated filter is recycled to the pretreatment unit.

21. The method of claim 16 further comprising the step of piping the effluent from the submerged aerated filter to a clarification unit prior to sending the effluent to the deep bed denitrification filter to reduce suspended solids within the effluent.

22. The method of claim 21 wherein a portion of the effluent stream from the clarification unit is recycled to the submerged denitrification reactor.

23. The method of claim 21 wherein a portion of the effluent stream from the clarification unit is recycled to the pre-treatment unit.

24. The method of claim 16 wherein the submerged denitrification reactor is an up flow filter.

25. The method of claim 16 wherein the submerged denitrification reactor is a down flow filter.

26. The method of claim 16 wherein the media beds of the submerged denitrification reactor and the submerged aerated filter comprises media particles ranging in size from about 9 mm to 45 mm in diameter.

27. The method of claim 16 wherein the media bed of the deep bed denitrification filter comprises media having a size of less than 6 mm in diameter.

28. The method of claim 16 wherein the submerged aerated filter comprises aerobic microorganisms to oxidize organic matter comprising carbonaceous organics, organic and ammonium nitrogens to produce NO_x, CO₂ and H₂O.

29. The method of claim 16 wherein the submerged denitrification reactor utilizes BOD within the wastewater influent as an organic carbon source for the anoxic microorganisms to denitrify the NO_x.

30. A biologically active reactor system for the treatment of wastewater, the system comprising:

one or more submerged denitrification reactors, the reactors comprising upright walls defining at least one compartment and a floor, the compartment comprising a media bed, the media bed comprising coarse, media particles ranging in size from about 6 mm to about 45 mm and a fixed biological film comprising biologically anoxic active microorganisms;

one or more submerged aerated filters in fluid communication with the one or more submerged denitrification reactor, the submerged aerated filter comprising a media bed, the media bed comprising coarse, media particles ranging in size from about 6 mm to about 45 mm and a fixed biological film comprising biologically aerobic microorganisms for oxidation of organic matter; and

one or more deep bed denitrification filters for removal of suspended solids and denitrification of oxidized nitrogens, the deep bed denitrification filter in fluid communication with the one or more submerged aerated filters, the deep bed denitrification filter comprising fine media particles of less than 6 mm;

a pre-treatment unit for receiving wastewater influent prior to piping to the submerged denitrification reactor;

piping from the deep bed denitrification filter back to the pretreatment unit to recycle dirty backwash from the deep bed denitrification filter to the wastewater influent entering the pre-treatment unit;

piping from the submerged aerated filter to the wastewater influent entering the pre-treatment unit;

piping from the submerged aerated filter back to the submerged denitrification reactor to recycle a portion of the wastewater effluent from the submerged aerated filter back to the submerged denitrification reactor;

one or more clarification units positioned between the submerged aeration filter and the deep bed denitrification filter to reduce suspended solids in the wastewater effluent from the submerged aerated filter to the deep bed denitrification filter; and

piping between the one or more clarification units and the one or more submerged denitrification reactors for recycling the clarified effluent to the submerged denitrification reactor.

31. A biologically active reactor system for the treatment of wastewater, the system comprising:

one or more submerged denitrification reactors, the reactors comprising upright walls defining at least one compartment and a floor, the compartment comprising a media bed, the media bed comprising coarse, uniformly sized mineral media particles and a fixed biological film comprising biologically anoxic active microorganisms;

one or more submerged aerated filters comprising biologically aerobic microorganisms for oxidation of organic matter in fluid communication with the submerged denitrification reactor;

the media bed of the submerged aerated filter comprising media particles ranging in size from about 9 mm to 45 mm in diameter; and

one or more deep bed denitrification filters for removal of suspended solids and denitrification of oxidized nitrogens, the deep bed denitrification filter in fluid communication with the submerged aerated filter.