Dublin Road Water Plant Treatment Capacity Increase Project Expanding Capacity and Treatment at an 80 MGD Surface Water Treatment Plant Enoch Nicholson, P.E. S. Dean Ramsey, P.E. CH2M HILL Mark Eppich, P.E. City of Columbus Division of Water
Presentation Topics System Overview Project Background Process Selection and Pilot Testing Project Phasing and Construction Contracts Current Project Status
SYSTEM OVERVIEW
City of Columbus, Ohio Water System
PROJECT BACKGROUND
Existing Treatment Plant Conventional Lime Softening Plant 65 MGD Capacity Rapid Mix Flocculator Turbidity Settling Rapid Mix Flocculator Softening Settling Re-carbonation Filters Clearwell POTASSIUM PERMANGANATE PAC R3 ALUM Turbidity Basins 1 & 2 SODIUM HYDROXIDE SODA ASH LIME Softening Basins 2 & 3 Recarbonation Basin 4 CO2 SODIUM HYPOCHLORITE FLUORIDE Dual Media Filters West East ZN ORTHO-PHOSPHATE Scioto River Residual R7 Residual R1 Residual R2 Residual R3 Residual R2
Plant Treatment Goals Total Hardness: 120 mg/l to 125 mg/l as CaCO3 Alkalinity: >35 mg/l as CaCO3 Total Organic Carbon (TOC): <2.0 mg/l Stage 2 DBP Compliance: Target 80% of Location Running Annual Average (LRAA) and Operational Evaluation Level Nitrate: < 10 mg/l as N (MCL) Atrazine: <2.5 ppb (MCL= 3.0 ppb) Comply with all primary drinking water regulations Taste and Odor 7
PROCESS SELECTION AND PILOT TESTING
Blue Ribbon Panel Process Evaluation Water Quality Finances Operations
Treatment Processes Selected for Pilot Organics Removal Ozone with Biological Active Carbon (BAC) Filtration GAC Post Filter Contactors GAC in Existing Filters Seasonal Nitrate Removal Nitrate Selective Strong Base Anion Exchange
11 Pilot Testing
12 DRWP Ozone Pilot System
13 DRWP Filter Pilot System
14 DRWP Pilot Filter System
15 DRWP Pilot Ozone and GAC Contactor Systems
DRWP Pilot TOC Reduction 3.0 2.5 2.0 1.5 1.0 0.5 0.0 Recarbonated Water (Pilot Influent) Ozonated Water BAC Filter (With Ozone) Antracite Filter (No Ozone) 16
DRWP Pilot System 3 Day TTHMs 80 70 60 3 day TTHM Formation (ug/l) 50 40 30 20 Filter 6 Average 3 day TTHM = 48 ug/l Filter 2 Average 3 day TTHM = 32 ug/l ** 10 0 6/22/2011* 9/9/2011 12/8/2011 3/8/2012 Pilot DBP Sample Date Filter 6 Anth/Sand 3 day TTHM (ug/l) Filter 2 BAC/Sand 3 day TTHM (ug/l) 17 Notes: *First DBP samples was collected late June 2011, no early June sample was available. Only Filters 4 and 6 were operational in June 2011. **No filter 2 DBP data available for June 2011, June 2011 Sample result predicted based on other sample results in order to calculated average.
DRWP Pilot Filter Performance 25000 0.300 20000 0.250 0.200 UFRV (gal/sf) 15000 10000 0.150 Turbidity (NTU) 0.100 5000 0.050 0 Filter 1 Ozonated GAC/Sand Filter 2 Ozonated BAC/Sand Filter 3 Ozonated Anthracite/Sand Filter 4 No Ozone GAC/Sand Filter 6 No Ozone Anthracite/Sand 0.000 Average UFRV Average Turb IX 18
DRWP Pilot Atrazine Removal Sample Low Ozone without Peroxide Low Ozone with Peroxide High Ozone without Peroxide High Ozone with Peroxide Influent Atrazine(ug/L) Effluent Atrazine (ug/l) Percent Removal 22 15 32% 22 12 45% 21 7.7 63% 22 6.9 68% 22 0.4 98% 19
Anion Exchange Pilot System Schematic
Anion Exchange Pilot System
Anion Exchange Pilot Testing Data Nitrate Concentration (mg/l as N) 10 9 8 7 6 5 4 3 2 DRWP IX Pilot Effluent Nitrate 139 Nitrate Samples in 13 Runs Alkalinity Concentration (mg/l as CaCO3) 80 70 60 50 40 30 20 DRWP IX Pilot Effluent Alkalinity 73 Alkalinity Samples in 10 Runs 1 10 0 0 Minimum Average Maximum Minimum Average Maximum 350 300 DRWP IX Pilot Effluent Chloride 69 Chloride Samples in 10 Runs 200 180 160 DRWP IX Pilot Effluent Sulfate 69 Sulfate Samples in 10 Runs Chloride Concentration (mg/l) 250 200 150 100 Sulfate Concentration (mg/l) 140 120 100 80 60 40 50 20 0 0 Minimum Average Maximum Minimum Average Maximum
Evaluation of IX Loading Rate Impacts Bed Volumes 300 250 200 150 100 50 0 Bed Volumes to start of Nitrate Breakthrough 262.6 263.7 Nitrate as N (mg/l) 2.22 2.29 10.7 gpm/sq ft (2 min EBCT) 4.6 gpm/sq ft (5 min EBCT) 10 9 8 7 6 5 4 3 2 1 0 Average Effluent Nitrate Data Includes 7 runs with 4.6 gpm/sq ft and 6 runs with 10.7 gpm/sq ft. These runs incorporated 93 and 46 samples, respectively.
PROJECT PHASING AND CONSTRUCTION CONTRACTS
DRWP Proposed Process Flow Diagram Scioto River Intake Low Service Pumps Rapid Mix Flocculator Turbidity Settling Rapid Mix Flocculator Softening Settling Re-carbonation Ozonation Filtration Ion Exchange Clearwells High Service Pumps POTASSIUM PERMANGANATE PAC R4 ALUM Turbidity Basins 1 & 2 Residual R1 SODIUM HYDROXIDE SODA ASH LIME Softening Basins 3 & 4 CO2 H2O2 OZONE QUENCH FILTER AID GAC Filters Rehab Existing ZN ORTHO-PHOSPHATE SODIUM HYPOCHLORITE FLUORIDE Scioto River Residual R7 Residual R1 Residual R2 New Recarbonation O3 New Ozone Residual R3 West East Residual R2 Refit Basin 4 for Softening Residual R5 Residual R6 New Ion Exchange Backwash Handling Facility Quarry Sludge Pump Station R1 R2 R6 Residual R4 New Facilities R3 R5 New Facilities NORMAL CHEMICAL ADDITION POINT 5/15/2013
DRWP Contract # 1 CONTRACT # 1 Contract # 1 Site Improvements New Sludge PS New Electrical Substation
DRWP Contract # 2 CONTRACT # 2 Contract #2 SCADA Backbone Filter Rebuild
DRWP Contract # 3 CONTRACT # 3 Contract #3 Basin #4 Modifications Recarbonation Ozonation
DRWP Contract # 4 CONTRACT # 4 CONTRACT # 4 Contract #4 Ion Exchange Backwash Equalization Chemical System Upgrades Electrical System Upgrades Control System Upgrades
DRWP Contract # 5 CONTRACT # 5 Contract #5 McKinley Quarry Sludge Pipeline
CURRENT PROJECT STATUS
Contract 1 Site Improvements
Contract 1 Sludge PS
Contract 1- Electrical Substation
Contract 2 Filter Retrofit
Contract 3 Ozone/Recarbonation Basin
Dublin Road Water Plant Treatment Capacity Increase Project Questions? Enoch Nicholson, P.E. enoch.nicholson@ch2m.com