1 / 25

New Nuclear Power and Climate Change: Issues and Opportunities

New Nuclear Power and Climate Change: Issues and Opportunities. Student Presentation Ashish K Sahu and Sarina J. Ergas University of Massachusetts - Amherst. Perchlorate Reduction in a Packed Bed Bioreactor Using Elemental Sulfur. Ashish K Sahu and Sarina J. Ergas. Background.

maire
Télécharger la présentation

New Nuclear Power and Climate Change: Issues and Opportunities

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. New Nuclear Power and Climate Change: Issues and Opportunities Student Presentation Ashish K Sahu and Sarina J. Ergas University of Massachusetts - Amherst

  2. Perchlorate Reduction in a Packed Bed Bioreactor Using Elemental Sulfur Ashish K Sahu and Sarina J. Ergas

  3. Background • Perchlorate (ClO4-) • Stable • Non reactive • Trace levels of Perchlorate • Disruption of hormone uptake in thyroid glands

  4. Geographic Contamination • No National Standards • MCL set by the Commonwealth of Massachusetts (2 mg/L) • California advisory levels (6 mg/L) • Other states (NY, NV, AZ, CO, TX) 18 mg/L Ref: ewg.org

  5. Sources of Perchlorate • Natural • Atmospheric Sources • Chilean nitrate fertilizer • Anthropogenic • Missiles, Rockets • Fireworks • Leather Tannery Industries • Fertilizers

  6. Treatment Processes • Physical Processes • Chemical Processes • Biological Processes • Combination of the above

  7. Perchlorate Treatment Processes Physical Destructive Process Hybrid Technologies Chemical Biological GAC Bioreactors Others RO/NF CC-ISEP Phytoremediation Reducing metals IX Electrodialysis Others (MBR) CSTR PFR Bio-remediation

  8. Outline • Biological Perchlorate Reduction • Use of Elemental Sulfur • Experimental Protocol • Results • Conclusions

  9. Heterotrophic microorganisms Use organic carbon as their carbon source Electron donors are methanol, lactate, ethanol, wastewater Autotrophic microorganisms Use inorganic carbon as their carbon source eg: NaHCO3 Electron donors are S, Fe0, H2 Biological Perchlorate ReductionPrinciple: Microorganisms convert perchlorate to chloride

  10. Use of Elemental Sulfur 2.87 S + 3.32 H2O + ClO4- + 1.85 CO2 + 0.46 HCO3- + 0.46 NH4+→ 5.69 H+ + 2.87 SO42- + Cl- + 0.462 C5H7O2N • Electron Donor: Elemental Sulfur • Electron Acceptor: Perchlorate • Carbon Source: Bi-carbonate • Low biomass production • Low nutrient requirements • Anoxic conditions • Alkalinity destroyed

  11. Advantages of Elemental Sulfur • Waste byproduct of oil refineries • Excellent packing media • Relatively inexpensive and easily available • Applications in packed bed reactors and permeable reactive barriers

  12. Objectives • Enrich a culture of Sulfur Utilizing Perchlorate Reducing Bacteria (SUPeRB) • Investigate the use of packed bed bioreactors to treat perchlorate contaminated waters by SUPeRB • Test the bioreactor for varying operating conditions

  13. Batch Culture Enrichments • Denitrification zone of Berkshire wastewater treatment plant, Lanesboro, MA • 5mg/L ClO4-, So and oyster shell, nutrients in groundwater • Analytical Techniques • pH • ClO4- concentration using IC (EPA method 314.0)

  14. Batch Culture Enrichment (SUPeRB)

  15. Packed Bed Reactor • Reactor inoculated with SUPeRB • Media: Elemental Sulfur pellets (4 mm), oyster shell (3:1 v/v) • Volume: 1 liter • Ports: 5 ports

  16. Packed Bed Reactor Operation

  17. Bioreactor Performance-Phase II(Effect of Empty Bed Contact Time (hrs))

  18. Bioreactor Performance-Phase II(Effect of Empty Bed Contact Time)

  19. Bioreactor Performance-Phase II(Effect of sulfur size particles)

  20. Bioreactor Performance-Phase II(Effect of Nitrate on Perchlorate Removal)

  21. Summary • SUPeRB reduced ClO4- from 5 mg/L to <0.5 mg/L in 15 days using S0 and OS • High levels of perchlorate (5-8 mg/L) were successfully reduced to < 0.5 mg/L in the bioreactor at an EBCT of 13 hours • Low levels of perchlorate (80-120 mg/L) were reduced to < 4 mg/L at an EBCT of 8 hours

  22. Summary… • Presence of nitrate did not inhibit perchlorate reduction • Perchlorate reduction was somewhat independent of media particle size

  23. Applications and Future Work • Pilot scale of system for perchlorate remediation • Ex-situ remediation • In-situ remediation by Permeable Reactive Barriers (PRBs)

  24. Acknowledgements • Water Resources Research Center (WRRC), TEI at UMass-Amherst • Massachusetts Technology Transfer Center (MTTC) for commercial potential • Advisor: Dr. Sarina Ergas • Teresa Conneely, Department of Microbiology for FISH and microbiology analysis • Tach Chu and Charlie Moe (High School) for culture and bioreactor maintenance

  25. Thank you for your kind attention Email: aksahu@acad.umass.edu SUPeRB is SUPERB!!!

More Related