1. Treatment Plant Ozone Retrofit Program California Unified Program 8 th Annual Training Conference February 8, 2006 Presented by: Paul G. Beswick Metropolitan Water District of Southern California Environmental Support Services (213) 217-5533pbeswick@mwdh2o.com

2. Southern California’s Imported Water California Aqueduct Colorado River Aqueduct SERVICE AREA Lower Salinity High DBPs High Salinity Low DBPs

3. Drivers for Treatment Improvements Water Quality –Regulatory compliance –Salinity management –Taste-and-odor control System Operations –Remove plant capacity limitations –Maximize flexibility of supply

4. Plant Process Layout

5. Plant Process Flow Diagram Meter Flash Mix FlocculationSedimentation Filtration Finished Water Reservoir Filter Aid Chlorine Ammonia Chlorine Caustic Poly Chlorine Alum/Ferric Floc Aid To Member Agency Connection Ozone Contactors Oxygen Generation Ozone Generation Hydrogen Peroxide Ozone Ozone Destruct AcidCaustic LOX

6. ORP General Design Criteria Plant Flow Range is 60 to 750 MGD Plant Flow Range is 60 to 750 MGD Design Ozone Dose of 2.6 mg/L at 750 mgd Design Ozone Dose of 2.6 mg/L at 750 mgd 8.6% Design Ozone Concentration 8.6% Design Ozone Concentration O3 Generation up 15,000 lb/day O3 Generation up 15,000 lb/day Contactors Designed for 10 Minute HDT Contactors Designed for 10 Minute HDT

7. Ozone Process Flow Diagram LOX TANK OPERATING = 2 STANDBY = 1 FUTURE = 1 OPERATING = 1 STANDBY = 1 DEFROST = 1 FUTURE = 1 LOX VAPORIZER LIQUID OXYGEN FEED GAS SYSTEM PSU OZONE GENERATOR OPERATING = 4 STANDBY = 1 FUTURE = 2 OZONE GENERATION SYSTEM OZONE CONTACTOR OZONE CONTACTOR SYSTEM VENT OZONE DESTRUCT SYSTEM OPERATING = 6 STANDBY = 0 FUTURE = 2 OPERATING = 5 STANDBY = 1 FUTURE = 4 OPERATING = 2 STANDBY = 1 FUTURE = 1 HEATER OZONE DESTRUCT CATALYST BED DESTRUCT BLOWER NITROGEN SYSTEM COMPRESSOR RECEIVER TANK DRYER OPERATING = 1 STANDBY IS A BOTTLE SYSTEM

8. ORP Chemical Storage UnitQtyCapacity OzoneN/A90 pounds LOX Tanks344,000 gal. ea. Hydrogen Peroxide (35%)22,000 gal. ea. Sulfuric Acid (93%)280,000/25,000 gal. Caustic (25%)8127K/50K gal. Chlorine390 ton rail cars Aqueous Ammonia (19%)413,000/10,000 gal. Sodium Hypochlorite (5.25%)22,000 gal.

9. LOX Tank Farm

10. Ozone Building

11. Ozone Generators

12. Ozone Contactor Schematic Ozone Ozone Feed Gas Ozone Off Gas Hydrogen Peroxide Raw Water

13. Contactor Gallery

14. Lessons Learned Standardized Alarm Beacons Disconnected Sample Line Vent to Contactor Warning Signals on Ozone Building Roof Safety Signs Throughout Facilities Automatic Shutoffs in Boiler Room New Gasket Material for Sulfuric Acid New Gasket Material for Ozone System Contactor Sample System Modification Added check valve at O3 generator outlet Seal Drain Sumps and Contactor Cover Plates 1 Year Life on O3 Ambient Detector Probes