A3: Contaminant Reduction, Life Cycle Impacts, and Life Cycle

A3: Contaminant Reduction, Life Cycle Impacts, and Life Cycle Costs of Ion

Exchange Treatment and Regeneration Treavor Boyer and Alysse Ness, University of Florida

Jane Zhang, University of South Florida

Introduction • Brief Description: Create a more sustainable approach to ion

exchange treatment and regeneration through the coupling of: • Ion exchange pilot plant study, • Ion exchange process models, • Life cycle assessment (LCA), • Life cycle cost analysis (LCCA), and • Integrated decision-support tool.

• Anticipated target utility characteristics: All utilities could benefit. • Emphasis on small systems that treat groundwater or surface

water high in DOC, bromide, nitrate, and/or hardness.

• Continuum of technology development:

Innovative Ion Exchange

IX and Combined IX

Regeneration Disposal NaCl v. non-NaCl

DOC Bromide Nitrate Hardness Ba, Sr

Contaminant-free

Pilot Plant Study • Cedar Key Water & Sewer

District, Cedar Key, FL • Serves approx. 900 customers

• Pilot plant operation • 2–3 days/week, 6–8 hours/day

• Ion exchange operation • 3 service–regeneration cycles • NaCl vs. NaHCO3 regeneration

• Analysis • On-site: UVA254, total hardness,

temperature, conductivity, Fe • UF: DOC, inorganic anions and

cations

Cedar Key Groundwater

Average water quality

TOC 6 mg C/L Conductivity 505 µS/cm

UVA254 0.176 1/cm pH 7.4 SUVA 3.0 L/(mg C-m) Iron 1 mg/L

Hardness 240 mg/L as CaCO3 January–February 2016

Cedar Key Groundwater

Ion Exchange Pilot Plant 2A - NaCl 2B – NaHCO3

Treated Water

Sample Locations: Raw water, Column 2A Effluent, Column 2B Effluent, CK Tap

Sampling

Sample Locations: 1. Column Influent 2. Column 2A Effluent 3. Column 2B Effluent 4. Cedar Key Tap Water

Test Plan Test Water Contaminants Resin [NaHCO3] [NaCl] Breakthrough Regen.

- - - % % [BV] QA/ QC

Cedar Key GW UVA254, DOC A-30 MP - 16 UVA254 removal < 90% 5

1 Cedar Key GW UVA254, DOC A-30 MP

8 16 UVA254 removal < 90% 5 8 Equiv.

2 Cedar Key GW UVA254, DOC A-72 MP

8 16 UVA254 removal < 90% 5 8 Equiv.

3 Cedar Key GW UVA254, DOC TBD 8 16 UVA254 removal < 80% 5

4 Cedar Key GW UVA254, DOC TBD 8 16 UVA254 removal < 90% 7.5

2.5

5 CK + NaBr UVA254, DOC, Br A-30 MP

8

16 UVA254, Br- removal < 90% 5 A-72 MP

Service Cycle Column Description

Inner Diameter 4 in Resin Bed Depth 28 in Resin Bed Volume 352 in3

1.5 gal 5.8 L

Service Cycle Service Flow Rate 0.4 gpm 1.512 L/m Operational Mode Co-current EBCT 3.8 min BV/hr 16 BV/h Flow Rate 4.6 gpm/ft2

Cycle #1 Cycle #3 Cycle #2

0

0.05

0.1

0.15

0.2

0.25

0 200 400 600 800 1000 1200 1400 1600

UV

254

(1/c

m)

BV Treated

Test 0: UV 254

Col Inf 2A Effleunt 2B Effluent CK Tap

0

1

2

3

4

5

6

7

8

9

0 200 400 600 800 1000 1200 1400 1600

DOC

(mg/

L)

BV Treated

Test 0: DOC

Column Inf 2A Effleunt 2B Effluent CK Tap


0

0.5

1

1.5

2

2.5

3

3.5

4

0 200 400 600 800 1000 1200 1400 1600

SUVA

(L/m

g-m

)

BV Treated

Test 0: SUVA

Col Inf 2A Effluent 2B Effluent CK Tap



0

0.5

1

1.5

2

2.5

0 200 400 600 800 1000 1200 1400 1600

Iron

(mg/

L)

BV Treated

Test 0: Iron

Col Inf 2A Effluent 2B Effluent CK Tap


0

100

200

300

400

500

600

700

800

0 200 400 600 800 1000 1200 1400 1600

Cond

uctiv

ity (u

S/cm

)

BV Treated

Test 0: Conductivity

Col Inf 2A Effluent 2B Effluent


4

5

6

7

8

9

10

0 200 400 600 800 1000 1200 1400 1600

pH

BV Treated

Test 0: pH

Col Inf 2B Effluent 2A Effluent

Regeneration Cycle Regeneration

Operational Mode Co-current

Regen Flow Rate 0.2 gpm

0.756 L/m

Regen EBCT 7.6 min

Regen BVs 5

Regen Total Time 39 min

Regen Total Volume 29.5 L

Regen 2A - NaHCO3

Regen 2B - NaCl

Rinse Cycle

Rinse Flow Rate 0.4 gpm

Operational Mode Co-current

Rinse EBCT 3.8 min

Rinse BVs 5

Rinse Total Time 19 min

Backwash

Backwash Flow Rate 0.4 gpm

Operational Mode Countercurrent

Backwash Total Time 10 min

Backwash Total Volume 4.2 gal

Backwash Volume 2.76 BV Sample: 3 samples/regeneration, 1 composite sample, 1 rinse sample Efficiency calculations based off of composite sample

Regeneration Results

Test 0: Regeneration Efficiency DOC On DOC Off Regen Eff DOC Remaining

g g % g Cycle 1 Col 2A 30.29 27.22 90 3.07

Col 2B 30.29 26.38 87 3.91 Cycle 2 Col 2A 17.70 10.86 61 6.84

Col 2B 18.54 13.74 74 4.80 Cycle 3 Col 2A 14.46 6.74 47 7.72

Col 2B 12.42 6.14 49 6.29

Modeling Framework

Modeling Framework: Fixed Bed Configuration

Zhang et al. 2016 Wat. Res.

Modeling Framework: Completely Mixed Flow Reactor

Bicarbonate-form anion exchange

Chloride-form anion exchange

2.2 mg/L DOC

1.7 mg/L DOC

LCA and LCCA: Regeneration Chemicals

Maul et al. 2014 Chemical Engineering J.

LCA and LCCA: Reactor Configuration

Amini et al. 2015 J. of Cleaner Production

Integrated Decision Model

Example: Development of Energy–Aquaculture Sustainability tool

Integration of Process Model with LCA/LCCA

Outputs and Outreach Completed: “Innovative Ion Exchange and Life Cycle Impacts for Small Water

Systems”, Story in WaterOperators.org, Winter 2015/2016 Scheduled: “Combined Ion Exchange in FL”, Small Systems course, U Colorado

Boulder, Spring 2016. “Innovative Ion Exchange and Regeneration”, US EPA Small

Systems webinar series, Fall 2016 Anticipated: Poster or talk entitled, “Pilot-Scale Evaluation of Bicarbonate-Form

Anion Exchange” at AWWA WQTC, Fall 2016 Manuscripts for submission to peer-reviewed journal, Spring 2017

Documents

A3: Contaminant Reduction, Life Cycle Impacts, and Life Cycle