1. Odor Control Benchmarking Study: Status & Preliminary Results
Dr. Carla Dillon, P.E. Orange County Sanitation District Chair, WEF Air Quality & Odor Control Committee

2. Agenda Background of Survey Participants/Survey Categories
Sample of Responses
Drivers
Outreach
Regulatory
Collection/Conveyance Findings
WRRFs Findings
Odor Control Spending
Needs

3. Background Timeline Value Benchmarking Data
Idea at Odor & Air Quality Specialty Conference 2014
In early 2015, team began planning desired information and questions
Survey beta tested started early 2016
Survey open to public June 2016 to December 20, 2016
Presented preliminary data at WEFTEC 2016 Workshop
Proposed half session for WEFTEC 2017 on the results
Value Benchmarking Data
Benefits for utilities
Benefits for vendors/manufacturers
Benefits for consultants
Benefits for researchers
Benefits for regulators

4. Who participated? – WRRFs (as of 9/2/2016)
 Characterizing the participants
Size, by population 20,000 to 6 million
Size by flow, 0.6 – 690 MGD
BOD: mg/L
TSS: mg/L

5. Survey Sections Categories (responses of 9/2/16)
General Participant Information – 74
Strategic Efforts, Outreach, Management – 68
Regulatory Compliance – 54
Collection System and Collection System Odor Control - 52
Odor Control at Water Resource Recovery Facilities – 44
Maintenance and System Integrity – 39
Capital Improvements in Odor Control – 38
Survey still open:

6. Sample of Responses from Preliminary Data
Results
Sample of Responses from Preliminary Data

7. What Drives Odor Control/Management Decisions?
Corrosion Control (5)
Employee safety (4)
Costs
Citizen lawsuits
Downstream processes
Water quality

8. Outreach and Response Action Levels None 18%
Any complaint, no nuisance 47%
D/T or OU 15.8% mostly 3-7 range
H2S 18%
10 ppb was common response
50 ppb peak at receptor
30 ppb scrubber discharge

9. Regulatory
66% of respondents are required to comply with an air/odor permit or regulations
Of those
Go beyond permit requirements? 46% responded YES
25.8%
19.4%
48.4%

10. Technology Used in Collection/Conveyance System
% of total units
% of treated airflow
Biofilter
20.3%
26.3%
Bioscrubber
5.5%
24.3%
Activated Carbon
66.7%
42.4%
Chemical Scrubber
6.3%
7.0 %
Iron Sponge
0.5% --
Ionization
No. of treatment units
Airflow treated, cfm
Total
378
615,566

11. Technology Used in Collection/Conveyance System – Chemical Addition

12. WRRF Questions by Process Area
Headworks/Preliminary
Primary
Secondary
Solids Processing
Gas Digester Systems and Support Facilities

13. WRRF liquid treatment at Headworks/Preliminary Treatment

14. WRRFs by Process – Headworks/Preliminary

15. WRRFs by Process – Headworks/Preliminary

16. Gaps/Needs
Planning/design, specifications and product information for more than H2S
Biotrickling filter chemistry: pH and precipitates
Liquid chemistries: complementary treatments, efficacy for non-H2S odors
High purity oxygen for treating low concentration gravity flows
Ventilation rates for indoor air quality as opposed to electrical code
Chemical fate and transport of odors

17. Benchmarking Workgroup
Rebecca Arvin-Colón, WEF staff
Carla Dillon, Orange County Sanitation District
Dennis Froehlich, Pima County Regional Wastewater Reclamation Department
Eric Hansen, Evoqua Water Technologies LLC
Mark Holstad, Albuquerque Bernalillo County Water Utility Authority
Dick Pope, Hazen and Sawyer
Ray Porter, Porter Odor Science
Philip Wolstenholme, Brown and Caldwell

18. Orange County Sanitation District
Thank You
WEF AQ&OC Committee Benchmarking survey:
Contact Information
Carla Dillon, D.P.A., P.E.
Orange County Sanitation District