First-of-It s Kind Industrial Ion Exchange Process Brings Municipal Potable Water Treatment Facility into Full Regulatory Compliance Mike Nixon, E.I. Phil Locke, P.E.
Agenda Background Treatment Alternatives Treatment Process and Design Startup and Testing Lessons Learned Project Benefits
Acknowledgements City of Bunnell Water Treatment Plant Ion Exchange Project City of Bunnell Fernand Tib Tiblier, Jr. Ron Cook Jason Palmer JEA Ryan Popko Bill Green Orica (IOXM) Water Care Ion Exchange System OEM Scott Mitchell
Background Bunnell City of Bunnell, Florida 1.0 MGD Water Treatment Plant Source - Floridan Aquifer Cascade Aeration Dual Media Filtration Disinfection Chloramines Finished Water Storage
City of Bunnell Population ~2,900 2 nd largest city in Florida (by area) Water age compounds water quality issues
FDEP Consent Order Issued October 2011 Maximum Contaminant Level (MCL) exceeded for Disinfection Byproducts (DBPs) Total Trihalomethanes (TTHMs) 120 ug/l average; 80 ug/l limit Schedule
Water Customer Concerns No suds zone Taste & odor Color Appliance damage
Project Goals and Initial Screening Reduce TTHMs Reduce Hardness Screening Evaluation Membrane Separation Lime Softening Ion Exchange
Initial Screening Evaluation Ion Exchange/Organix Membrane Softening Cation Exchange
Membrane Treatment Pros Consistent removal of DBP precursors & hardness Highly effective and reliable Cons Concentrate management limited disposal options Additional source water supply needed Cost prohibitive Consent Order timeline likely not met
Lime Softening Pros Excellent hardness removal Efficient Cons O&M client s poor previous experience Limited dissolved organic carbon removal Requires additional treatment (e.g., anion exchange) for effective organics removal
Ion Exchange Pros Dual Media Configuration Anion exchange to remove DBP precursors Cation exchange to remove hardness Small waste volume Consent Order schedule can be met Cons Regeneration brine waste disposal Increased sodium & chlorides in finished water
TTHM Treatment Options Matrix Primary Criteria Weight Score Technology Lime Softening Ion Exchange RO/NF Weighted Score Score Weighted Score Score Weighted Score Cost Capital Costs 15.0% 5 0.75 4 0.6 2 0.3 O&M Costs 15.0% 4 0.6 3 0.45 2 0.3 Technical Feasibility Finished Water Quality 20.0% 2 0.4 4 0.8 5 1 Disinfection Demand 5.0% 2 0.1 4 0.2 5 0.25 Proven Implementation 5.0% 5 0.25 4 0.2 5 0.25 Water Loss 3.0% 5 0.15 4 0.12 2 0.06 Treatment Waste 2.0% 5 0.1 3 0.06 1 0.02 Footprint 1.0% 4 0.04 5 0.05 3 0.03 Operation & Maintenance Safety 5.0% 2 0.1 5 0.25 5 0.25 Operator Training 4.0% 3 0.12 2 0.08 1 0.04 Maintenance 5.0% 1 0.05 3 0.15 3 0.15 Schedule Consent Order Deadline 15.0% 5 0.75 5 0.75 5 0.75 Permitting 5.0% 5 0.25 5 0.25 4 0.2 Total 100.0% 3.66 3.96 3.60 *Score 1-5, with 5 best
Pilot Test 5-10 gpm 4-8 minute resin contact time 600 bed volumes for optimal treatment 80% DOC reduction 90% reduction in true color 50% hardness removal TTHM reduced from ~120 ug/l to ~ 20 ug/l
WTP Process Flow Diagram
MIEX Process Flow Diagram Brine Tank Waste Brine
Historical TTHM Data Sample TTHM EPA MCL Sample TTHM EPA MCL Sample TTHM EPA MCL Date ug/l ug/l Date ug/l ug/l Date ug/l ug/l 01/2005 251 80 06/2009 137 80 11/2010 169 80 12/2005 61 80 09/2009 48 80 12/2010 96 80 03/2006 73 80 10/2009 64.7 80 12/2010 221 80 05/2006 46 80 10/2009 78.7 80 12/2010 179 80 08/2006 53 80 10/2009 131 80 01/2011 219 80 11/2006 64 80 12/2009 86.8 80 01/2011 143 80 02/2007 45 80 03/2010 51.6 80 02/2011 145 80 06/2007 53 80 05/2010 87.9 80 05/2011 274 80 10/2007 49 80 08/2010 181 80 07/2011 382 80 08/2008 44 80 10/2010 221 80 07/2011 331 80 *Highlighted cells indicate exceedance of EPA maximum contamination limit (80 ug/l)
Source Water Quality Parameter Well #3 Well #4 Well #5 Well #7 Well #8 ph 7.9 7.8 7.9 8.1 7.9 DOC (mg/l) 6.4 8.6 6.8 5.7 4.9 UV254 (cm -1 ) 0.152 0.206 0.195 0.160 0.183 True Color (CU) 12 4 16 12 10 Apparent Color (CU) 26 57 24 13 11 H 2 S (µg/l) 64 1059 1348 1883 1798 Turbidity (NTU) 0.27 1.10 3.40 1.96 1.29 Iron (mg/l) 0.59 0.90 0.69 0.89 0.02 Sulfate (mg/l) 0.5 0.0 1.3 1.0 23.5 Hardness (mg CaCO 3 /L) 278 305 309 357 411 Calcium Hardness (mg CaCO 3 /L) 259 275 282 281 342 Sodium (mg/l) 25 25-66 66 Chloride (mg/l) 40 40 120 260 260 Conductivity (µmhos/cm) 752 660 913 929 1291 *Data from Pilot Study - February to March, 2012.
Design Considerations Site constraints Maintain operations Sole source OEM Performance guarantees Funding requirements
Ion Exchange System MICo Co-removal system Anionic resin for DOC removal Cationic resin for softening 1 st ever full-scale installation
Startup & Testing Equipment Startup Process startup Alarm simulations Training and water quality testing 14-day performance test
Water Quality Results Summary
DOC Levels and Removal
UV 254 Removal 0.033
DOC versus UV 254
Hardness Comparison
Cyclical Hardness Removal
Filtered Water Turbidity 2 NTU 1 NTU
Lessons Learned Use SCADA for startup data and MORs Anticipate some resin carryover Include provisions for chorine injection upstream of filters Make sure turbidimeter source has enough pressure
Project Benefits Achieved DBP compliance Reduced hardness Minimized footprint using coremoval ion exchange Met schedule goal & was funded 50% from USDA Residents are happy!!
Questions Contact Information: Mike Nixon, EI mnixon@mckimcreed.com 941.379.3404 31 Phil Locke, PE plocke@mckimcreed.com 727.442.7196