1 / 30

Breaking Loop of Phosphorus Recycle – Side Stream Phosphorus Removal/Recovery

NC AWWA-WEA 93 rd Annual Conference. Breaking Loop of Phosphorus Recycle – Side Stream Phosphorus Removal/Recovery . Yuan Fang, Ph.D., P.E. Chris Wilson, Ph.D., P.E. Dimitrios Katehis, Ph.D., P.E. . November 12 , 2013 | Concord, NC. Outline. Phosphorus Resource

mandar
Download Presentation

Breaking Loop of Phosphorus Recycle – Side Stream Phosphorus Removal/Recovery

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. NC AWWA-WEA 93rd Annual Conference Breaking Loop of Phosphorus Recycle – Side Stream Phosphorus Removal/Recovery Yuan Fang, Ph.D., P.E. Chris Wilson, Ph.D., P.E. Dimitrios Katehis, Ph.D., P.E. November 12, 2013 | Concord, NC

  2. Outline • Phosphorus Resource • Phosphorus Mass Balance in Conventional WWTP and EBPR Plant • Sidestream Phosphorus Removal and Recovery • Model Assistance in Implementing Sidestream P Removal / Recovery • Summary

  3. Outline • Phosphorus Resource • Phosphorus Mass Balance in Conventional WWTP and EBPR Plant • Sidestream Phosphorus Removal and Recovery • Model Assistance in Implementing Sidestream P Removal / Recovery • Summary

  4. Phosphorus Resource • An essential nutrient for all plants and animals • Non-renewable resource that takes 10-15 million years to cycle naturally (phosphate rock) • No substitute available, cannot be manufactured • P reserves worldwide are 71 billion tons

  5. Phosphorus Reserve According to the Global Phosphorus Research Initiatives, current high-grade reserves will be depleted within 50-100 years.

  6. Outline • Phosphorus Resource • Phosphorus Mass Balance in Conventional WWTP and EBPR Plant • Sidestream Phosphorus Removal and Recovery • Model Assistance in Implementing Sidestream P Removal / Recovery • Summary

  7. Phosphorus Mass Balance in Conventional WWTP Disinfection Plant Effluent Influent Aeration Tank (Conventional) Primary Clarifier Secondary Clarifier 269 lbd 195 lbd 289 lbd (72%) (9.2 mg/l) (6.7 mg/l) WAS RAS Primary Sludge Thickener Secondary Sludge Thickener 89 lbd Anaerobic Sludge Digester 16 lbd (6%, Internal P loading) Dewatering Sludge Disposal 74 lbd (1.8% P/TSS) (28%)

  8. Phosphorus Mass Balance in EBPR Plant Disinfection Plant Effluent Influent Aeration Tank (EBPR) Primary Clarifier Secondary Clarifier 269 lbd 56 lbd 514 lbd (21%) (9.2 mg/l) (1.9 mg/l) WAS (PAO) RAS Primary Sludge Thickener Secondary Sludge Thickener 441 lbd (increase 4x) Anaerobic Sludge Digester 228 lbd (44%, internal P loading) Dewatering Sludge Disposal 213 lbd (4% P/TSS) (79%)

  9. Phosphorus Mass Balance in EBPR Plant Disinfection Plant Effluent Influent Aeration Tank (EBPR) Primary Clarifier Secondary Clarifier WAS (PAO) RAS Primary Sludge Thickener Secondary Sludge Thickener NH4+ , PO43- release, Nuisance Struvite Precipitation Anaerobic Sludge Digester Dewatering Biosolids with higher P% Sludge Disposal

  10. Breaking P-Loop in EBPR Plant Disinfection Plant Effluent Influent Aeration Tank (EBPR) Primary Clarifier Secondary Clarifier WAS (PAO) RAS Primary Sludge Thickener Secondary Sludge Thickener Treated Sidestream with Reduced PO4-P Anaerobic Sludge Digester Sidestream with concentrated NH3-N, PO4-P P Removal / Recovery Dewatering Sludge Disposal

  11. Outline • Phosphorus Reserve • Phosphorus Mass Balance in Conventional WWTP and EBPR Plant • Sidestream Phosphorus Removal and Recovery • Model Assistance in Implementing Sidestream P Removal / Recovery • Summary

  12. Sidestream Phosphorus Removal and Recovery Options Physico-Chemical Treatment • Trivalent Metal Complexion/Precipitation • Al3+, Fe3+ , widely used • Increase biosolids production (hauling cost) • Struvite Recovery • Mg2+ + NH4+ + PO43- + 6H2O  Mg(NH4)PO4·6H2O (MAP) • Produce fertilizer with market value • Reduce N loading from sidestream as well

  13. Outline • Phosphorus Reserve • Phosphorus Mass Balance in Conventional WWTP and EBPR Plant • Sidestream Phosphorus Removal and Recovery • Model Assistance in Implementing Sidestream P Removal / Recovery • Summary

  14. Model Layout for Case Study Facility Centrifuge feed tube - 12 weeks following commissioning. Struvite Crystal Build-up, Centrate Sump Pump Volute and Impeller Sidestream Treatment

  15. Case Study Facility Process Model, TP Balance EBNR Process (Five-Stage Bardenpho) Unit: pounds per day 4,160 3,174 1,110 1,110 (4.4 mg/l) Side Stream 2,232 (115% of influent P) 1,928 1,928 986 2063 986 0 405 1,827 1637 1637 3,699 3,699 3,294 1,637 1,637 TP Balance Total In: 1,928+1,637 = 3,565 lbd Total Out: 1,110+2,453 = 3,563 lbd Side Stream: 1,827+ 405 = 2,232 lbd 189 1,638 1,827 4,091 4,091 2,453 2,453 Centrate Recycle NH4-N: 650 mg/l Ortho-P: 459 mg/l 797

  16. Case Study Facility Process Model, TP Balance EBNR Process Plus Sidestream Ferric Addition Unit: pounds per day TP Balance 255 (1.01 mg/l) Total In: 1928+1637 = 3565 lbd Total Out: 255+3305 = 3560 lbd Side Stream: 365+484 = 849 lbd WRF Influent Side Stream 849 (44%) 1928 365 484 Sludge from Other WRF 1637 377 950 kg Fe/d 3653 Centrate Recycle NH4-N: 708 mg/l Ortho-P: 7.5 mg/l 3305

  17. Case Study Facility Process Model, TP Balance EBNR Process Plus Struvite Recovery_Method 1 Unit: pounds per day TP Balance (lbd) 267 (1.06 mg/l) Total In: 1928+1637 = 3565 lbd Total Out: 267+2078+1216 = 3561 lbd Side Stream: 337 + 150 = 487 lbd 1928 Side Stream 487 (25%) 337 150 1637 1254 3333 Recycle Stream NH4-N: 533 mg/l Ortho-P: 11 mg/l 2078 1254 1216

  18. Case Study Facility Process Model, TP Balance • EBNR Process Plus Struvite Recovery_Method 2 Unit: pounds per day TP Balance 249 (1.0 mg/l) Total In: 1928+1637 = 3565 lbd Total Out: 249+1967+1351 = 3567 lbd Side Stream: 239 lbd WRF Influent 1928 Side Stream 239 (12%) 239 Sludge from Other WRF 341 1637 1152 3118 Centrate Recycle NH4-N: 156 mg/l Ortho-P: 16 mg/l 1967 1351 1493

  19. Comparison_Biosolids

  20. Comparison_Sidestream Nutrient Loads

  21. Payback Period Analysis for Struvite Recovery Note: Using ferric iron addition as the baseline for comparison O&M Cost: O&M labor, power, chemical, lab O&M Saving: Aeration, chemical (ferric), sludge hauling, market value of struvite

  22. Outline • Phosphorus Reserve • Phosphorus Mass Balance in Conventional WWTP and EBPR Plant • Sidestream Phosphorus Removal and Recovery • Model Assistance in Implementing Sidestream P Removal / Recovery • Summary

  23. Summary • Sidestream P removal/recovery is beneficial to EBPR system in terms of • Reduce sidestream P load to the main plant • Improve bio-P stability • Reduce nuisance struvite precipitation • Whole plant model is an effective tool to • Evaluate sidestream treatment performance • Assist in optimizing struvite recovery

  24. Summary • Compare to metal addition, struvite recovery has following advantages: • Reasonable payback period • Reduce aeration need and biosolids hauling cost • Produce struvite that has market value • Reduce P content in biosolids • Support sustainability of P resource

  25. Several proprietary processes exist to manage struvite precipitation Multiform Harvest Cone DHV Crystalactor Ostara Pearl Process Veolia Aeration/CO2 stripping

  26. Struvite Recovery Process Configuration

  27. Thank you for your time! QUESTIONS? Contact Information: • Yuan Fang, Ph.D., P.E. yfang@greeley-hansen.com

  28. Several proprietary processes exist to manage phosphorous precipitation Multiform Harvest Cone DHV Crystalactor Ostara Pearl Process Veolia Aeration/CO2 stripping

  29. Biosolids Phosphorus Management Regulations

  30. Typical Sidestream Characteristics 30

More Related