Utilization of Ozone for Disinfection and EDC Removal at CCWRD

Presentation Transcript

Utilization of Ozone for Disinfection and EDC Removal at CCWRD Doug Drury, Ph.D. Agent General Manager Clark County Water Reclamation District Shane Snyder, Ph.D. R&D Project Manager Southern Nevada Water Authority

Objectives Expansion of momentum office 110 to 150 MGD fortunate time to use best in class innovation Investigate ozone for cleansing and developing contaminant expulsion Use seat scale assessments for beginning plausibility Engineering examination to gauge capital and O&M costs analyze UV and ozone sanitization

Why Ozone? Intense disinfectant No remaining (contrasted with chlorine) Stronger oxidant (looked at chlorine/UV) Three ozone plants in Southern Nevada AMS 600 MGD drinking water River Mountains 300 MGD drinking water Big Bend (Laughlin) 20 MGD drinking water Ozone demonstrated innovation for sanitization & contaminant evacuation

SNWA Treatment Studies

Emerging Contaminants 1994: Britain finds angle underneath WWTP outfalls with side effects of presentation to estrogenic mixes 1996: USGS reports comparative discoveries in carp from the Las Vegas Bay, Lake Mead 1996: EPA reports endocrine interruption in fish from Minnesota close WWTPs 1996: Amendment to SDWA commands EPA build up a screening program for EDCs 1997: SNWA starts observing and angle ponders for EDCs

SNWA EDC Research 1997: Initial screening of LV Wash & Lake Estrogen mixes distinguished in Wash & Bay No estrogens identified in drinking water First recognition of pharmaceuticals 1998: Fish confined in Lake Mead Subtle contrasts in fish from LV Bay, yet not emotional as observed in USGS concentrates 2000: DOD financed investigation of fish Small contrasts among LV Bay & Overton Perchlorate not identified with EDC impacts in fish 2003-Current: Monitoring of Lake Mead

SNWA Monitoring 1998 Compound Usage ng/L

Adapted from USGS Report 02-385 Boyd & Furlong

2001-2002 USGS Monitoring of Lake Mead Adapted from USGS Report 02-385 Boyd & Furlong - 2002

Southern Nevada WWTPs 2003 (ng/L) WWTP#1 WWTP#2 WWTP#3

AwwaRF Treatment Study Evaluation of traditional and propelled water treatment for EDC expulsion Disinfection: UV, chlorine, ozone Membranes: RO, NF, UF, MF, EDR, MBR Activated carbon Biological Ion trade SNWA got $350,000 from AwwaRF Project finished in mid 2005

Ethinyl estradiol 17 β Estradiol Progesterone Estrone Estriol Androstenedione Steroids Testosterone

Triclosan Trimethoprim Sulfamethoxazole Erythromycin Antimicrobials

Dilantin Carbamazepine Caffeine Diazepam Fluoxetine Meprobamate Psychoactive

Diclofenac Naproxen Ibuprofen Acetaminophen Analgesics Hydrocodone

Gemfibrozil Pentoxifylline Iopromide TCEP Metolachlor Musk Ketone Galaxolide Atrazine Others

UV 40mJ/cm 2

Chlorine 3.5 mg/L 24 hr

<30% Removal 30-70% Removal >70% Removal Musk Ketone Meprobamate Testosterone TCEP Atrazine Progesterone Iopromide Androstenedione Estriol Ethynylestradiol Estrone Ozone 2.5 mg/L Estradiol Erythromycin-H2O Sulfamethoxazole Triclosan Trimethoprim Naproxen Diclofenac Ibuprofen Hydrocodone Acetaminophen Carbamazepine Dilantin Diazepam Caffeine Fluoxetine DEET Metolachlor Galaxolide Pentoxifylline Gemfibrozil

Free Chlorine versus Chloramine TCl (2 mg/L) TCl 2 (3 mg/L) FCl 2 (3 mg/L) Triclosan Diclofenac Hydrocodone Naproxen Sulfamethoxazole Erythromycin-H2O Trimethoprim Gemfibrozil 0 10 20 30 40 50 60 70 80 90 100 Percent Removal

CCWRD Evaluation 200 L of tert. treated emanating gathered preceding UV sterilization June 2005 Ozone request/rot decided 1-L/min move through "small scale pilot" 12 contactors with 2 min. contact time every Ozone infusion in 1 st contactor just Organic contaminants, microorganisms, and estrogenicity (bioassay) checking Samples gathered at different contact times

6 CCWRD Bench Ozone Decay 5 O3=6.9 mg/L 4 O3=6.0 mg/L O3=4.3 mg/L O3=1.8 mg/L 3 Dissolved Ozone Residual (mg/L) 2 1 0 5 10 15 20 25 30 Contact Time (min)

Raw Sewage-AVE Secondary Effluent AVE 3 mg/L 6 mg/L 8 mg/L Analyte ng/L ng/L ng/L ng/L ng/L Iopromide 37 22 6 2 ND Naproxen 13200 13 ND Ibuprofen 11950 19 ND Diclofenac 28 54 ND Triclosan 1590 85 112 50 72 Gemfibrozil 1105 ND Galaxolide 1680 1169 46 ND Musk Ketone 225 133 83 72 42 EEq ng/mL >40 0.626 ND Total Coliform >16,000,000 6750 <2 Fecal Coliform >16,000,000 2675 <2

Before Ozonation After Ozonation

Conclusions Ozone is compelling for sanitization and expulsion of rising contaminants No impeccable treatment RO/NF layers = saline solution and water misfortune Activated carbon = transfer/recovery Disinfection = results Ozone can expel cell estrogenicity Effects on fish ought to be assessed European researchers discovered same impact

Implications for CCWRD

Conclusions Southern Nevada has broad history & ability in ozone innovation Costs for ozone and UV are practically identical for sterilization in reuse application UV is not oxidative at purify measurement Ozone gives purification & oxidation UV subject to regrowth post-cleansing Neither UV nor ozone have lingering issues Contact times from pilot would be sensible ≈ 8-20 min contact time for ozone ≈ 90 min contact time for chlorine

Future Efforts Repeat study January 2006 amid winter season peroxide expansion for cutting edge oxidation Plant extension outline choices will happen in 2006 layers versus ordinary channels ozone versus UV on-line by roughly 2009 (?) Monitoring endeavors of Lake Mead will proceed with SNWA examinations F&W, USGS, BOR, NPS all have on-going endeavors CWC's SCOP versatile administration arrange

Questions Doug Drury, Ph.D. ddrury@cleanwaterteam.com Shane Snyder, Ph.D. shane.snyder@snwa.com