1 / 13

PHOSPHORUS REMOVAL ON DAIRIES IN THE PACIFIC NORTHWEST

PHOSPHORUS REMOVAL ON DAIRIES IN THE PACIFIC NORTHWEST. Applying a Cone Shaped Fluidized Bed Phosphorus Crystallizer Ron Sheffield – U of Idaho Keith Bowers – Multiform Harvest Inc. Joe Harrison – U of Washington. Magnesium, Struvite Precipitation. Magnesium ammonia phosphate crystal

pauline
Télécharger la présentation

PHOSPHORUS REMOVAL ON DAIRIES IN THE PACIFIC NORTHWEST

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. PHOSPHORUS REMOVAL ON DAIRIES IN THE PACIFIC NORTHWEST Applying a Cone Shaped Fluidized Bed Phosphorus Crystallizer Ron Sheffield – U of Idaho Keith Bowers – Multiform Harvest Inc. Joe Harrison – U of Washington

  2. Magnesium, Struvite Precipitation • Magnesium ammonia phosphate crystal • Similar to a Kidney Stone • Equilimolar concentrations of Mg, NH3 and PO4 • Naturally occurring in waste systems • Overflow pipes, recycle elbows, pump impeller • Very common in municipal and swine waste systems • Historically produced slow release fertilizer

  3. Magnesium, Struvite Precipitation • Theory: Magnesium acts as a coagulant to settle out phosphorus. • How it Works: Magnesium, ammonium and phosphate ions when at a pH of 7 to 11 will combine to form Struvite (MgNH4PO4*6 H2O) • Removal Efficiency: • 90% reduction in SP from a swine anaerobic treatment lagoon in NC

  4. Laboratory Crystallizer

  5. Fluidized-Bed Struvite (MgNH4PO4) Crystallizer Treated Effluent Crystallizer Cone Mg Dissolving Cone (optional) Anhydrous Ammonia Wastewater In Mg Harvested Struvite 4-20-0.25 Pilot Scale Crystallizer 2 gpm

  6. Si-Ellen Farm • 4,000 cow open lot • Flush feeding alleys • Primary Solids Removal – Slope Screen • Secondary Solids Removal – Gravity Basin • 3 Wastewater Storage Ponds - 18M gallons

  7. Werkhoven Dairy • 600 cow freestall • Flush manure handling • Primary Solids Removal – Gravity Basin • 3 Wastewater Storage Ponds - 18M gallons • Wastewater Analysis • TP = 85 mg/l • PO4 = 25.4 mg/l • pH = 7.8

  8. Results

  9. Crystalline Product • Advantages • Non-sludgy • Crystalline structure • Easily dried and handled • Concentrated Fertilizer - 4:20:0.25 Average ID analysis • Organic Product??? • Limitations • Slow Release • Low Nitrogen

  10. Wastewater Solubility vs Equilibrium - Ohlinger et al. 1998

  11. Conclusions • Cone shaped fluidized bed crystallizer was successful in removing P from dairy wastewater • TP removal was observed to be lower than as demonstrated with swine lagoon wastewater • PNW dairies showed higher Mg and TAN: possibly reducing TP removal via struvite harvesting

  12. Next Steps…..Struvite Crystallization • Acidification Pre-Treatment • pH, retention time • Portable Struvite Crystallizer • Trailer mounted • Evaluate various wastewaters • Full-Scale Crystallizer: >10M gallons/year • Organic Certification • Crop Response

  13. Next Steps…..Anaerobic Digestion • Phosphorus Pretreatment • Digester not for energy production rather as P removal systems • Investigate lowest Hydraulic Retention Time (HRT) to achieve highest PO4:TP • Smaller & Cheaper digester • Follow with Struvite Crystallization

More Related