New Nuclear Power and Climate Change: Issues and Opportunities

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

Department of Civil and Environmental Engineering

Perchlorate Reduction in a Packed Bed Bioreactor Using Elemental Sulfur

Ashish K Sahu and Sarina J. Ergas

3Department of Civil and Environmental Engineering

Background

Perchlorate (ClO4-)

• Stable• Non reactive

Trace levels of Perchlorate• Disruption of hormone uptake in thyroid glands


Geographic Contamination

No National Standards MCL set by the

Commonwealth of Massachusetts (2 g/L)

California advisory levels (6 g/L)

Other states (NY, NV, AZ, CO, TX) 18 g/L

Ref: ewg.org


Sources of Perchlorate

Natural• Atmospheric Sources• Chilean nitrate fertilizer

Anthropogenic• Missiles, Rockets • Fireworks• Leather Tannery Industries• Fertilizers


Physical Processes Chemical Processes Biological Processes Combination of the above

Treatment Processes


Perchlorate Treatment Processes

Physical Destructive Process

ChemicalBiological

GAC

RO/NF

Electrodialysis

CC-ISEP Bioreactors

Hybrid Technologies

Bio-remediation

Phytoremediation

IX

Others

Others (MBR)CSTR PFR

Reducing metals


Outline

Biological Perchlorate Reduction Use of Elemental Sulfur Experimental Protocol Results Conclusions


Biological Perchlorate ReductionPrinciple: Microorganisms convert perchlorate to chloride

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


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


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


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


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)


Batch Culture Enrichment (SUPeRB)

0.0

1.0

2.0

3.0

4.0

5.0

0 100 200 300 400

Days

ClO

4- m

g/L


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


Packed Bed Reactor Operation

Experimental Phase

Perchlorate concentration

mg/L

EBCT hrs

Recirculation RatioQR/Q

So particle

size

Phase I 5-8 13-100 Intermittent at(40-1,500)

4 mm

Phase II

Reactor 1 0.08-0.12 25-30 50-1,000 4 mm

Reactor 2 0.08-0.12NO3

--N (10 mg/L)8-30 None 4 mm

Reactor 3 0.08-0.12 8-30 None 0.85 mm


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

020406080

100120140

0 50 100 150

Days

ClO

4- g

/L

Influent Effluent

30 15 12 8


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

7589 87

96

0

20

40

60

80

100

120

28 15 11 7.5

Empty Bed Contact Time (hrs)

Ave

rag

e %

ClO

4- rem

ova

l


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

6560

90

0

20

40

60

80

100

21 7.6 4

Empty bed contact time (hrs)

Ave

rag

e %

ClO

4- re

mo

val


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

0

2

4

6

8

10

12

14

0 5 10 15 20 25 30 35

Distance cm

NO

3- N

mg

/L

0

20

40

60

80

100

ClO

4- g

/L

Nitrate Perchlorate


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 g/L) were reduced to < 4 g/L at an EBCT of 8 hours


Summary…

Presence of nitrate did not inhibit perchlorate reduction

Perchlorate reduction was somewhat independent of media particle size


Applications and Future Work

Pilot scale of system for perchlorate remediation

Ex-situ remediation In-situ remediation by Permeable Reactive

Barriers (PRBs)


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

Department of Civil and Environmental Engineering

Thank you for your kind attention

Email: [email protected]

SUPeRB is SUPERB!!!

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New Nuclear Power and Climate Change: Issues and Opportunities