Department of Chemical and Natural Gas Engineering Texas A&M University, Kingsville

1. SUPERVISORs: Dr. carlmurphy (tamuk) DR. Charles Glass (howard university) by: Adebanjo o. Ibironke EVALUATING THE EFFECTIVENESS OF ACCELL FOR ODOR AND CORROSION CONTROL IN WASTEWATER COLLECTION SYSTEM Manager: Mr. HIRAM Tanner (DC Water) Department of Chemical and Natural Gas Engineering Texas A&M University, Kingsville

2. The Problem Odor Under anaerobic conditions and absence of other electron acceptors as nitrate, microbiological reactions of sulfate reducing bacteria (SRB) in the sewer biofilm result in sulfate reduction to sulfide. • SO4= + 8H+→ S= + 4H2O • S= + 2H+ → H2S (hydrogen sulfide)

3. MECHANISM OF H2S GENERATION • On a wastewater profile in sewer, below the bulk water and next to the submerged wall, a thin layer of biofilm is fully formed after two weeks. The layer is composed mainly of bacteria and inert solids compacted by zooglea -a biologically secreted protein. Here, sulfate reducing bacteria (SRB) within the anaerobic zone strips the sulfate ion (SO42-) of its oxygen and uses this as a source of oxygen for digesting organic matter.

4. Hydrogen Sulfide (H2S) is a dense, toxic, colorless gas, that is not only odorous, but, also, very corrosive to infrastructure. H2S (ppm)Hazard Property 0.1 - 0.3 Detectable 3 - 5 Rotten Egg 10 – 50 Headaches/Nausea 100 –300 Conjunctivitis/Respiratory Irritation (imperceptible to smell) 500 -1000 Immediate Collapse with Respiratory Paralysis 1000-2000 Death

5. H2S + 202  H2SO4 S= + 2H+ H2S SO4= -202  S= Corrosiveness of H2S On the sewer pipe crown, surface and wall resides aerobic bacteria, mainlythiobacillus. These bacteria thrive on the moist wall of sewers and they oxidize gaseous hydrogen sulfide into sulfuric acid. • Sulfuric acid readily deteriorates the structural integrity of concrete, iron and steel in the moist, oxidizing atmosphere of a wastewater treatment plant. • Copper contacts and components of electrical systems will rapidly oxidize to black copper sulfate in the presence of small amounts of hydrogen sulfide.

6. CONCERNS Corrosion • Sewer System Assessment and Water Facility Plan, 2009 indicated: 88% defect in inspected sewers and 94% defect in manholes. • Approximately, 7000 linear feet of sewers were found in need of either rehabilitation or replacement. Toxicity • Daily exposure to noxious odors resulting in heightened health risks to employees • Unpredictable pump systems failures due to structural deterioration of metals

7. COST • Fiscal year 2009 -2018 Capital Improvement Program budget for DC Water, rehabilitation cost of sanitary sewer lines was estimated to $413 million = 11% of the total budget of $3.8 billion. • Estimates $38B in replacement costs in United States annually in collection and distribution systems due to corrosion • Water & sewer utility agencies face the same costs as the damage caused by Hurricane Katrina but on an annual basis

8. Washington DC Collection System • 1800 miles Sanitary and Combined Sewers; 600 miles of Storm Sewers • 9 Sanitary and 16 Stormwater Pumping Stations • 60 CSO (combined sewer overflows) Outfalls and 95 CSO Structures. • Largest Sewer: Northeast Boundary 22 feet by 23’6” near RFK (Robert F. Kennedy) Stadium • Longest: Potomac Interceptor 50 miles from Dulles International Airport to the Potomac Pumping Station • Oldest Sewer: Tiber Creek first sections completed in early 1850’s • Largest Pumping Station: O Street 500 mgd Storm, 45 mgd Sanitary. Built 1908

10. To find a Treatment Process for Sewers • Existing Asset: • Sewers are Longitudinal Dynamic Reactors – By not treating sewerage - Flow becomes anaerobic and produces corrosive gases • Treatment in Sewers Have Lower CIP (capital improvement program) Impact Versus Building or Modifying Facilities at the Plant • Treatment in Sewers Is Part of The Solution: • Protect the Environment - Reduce Noxious Odors and Greenhouse Gases • Protect the Public - Reduce Risk of Sewer Collapse Due to Corrosion • Protect Assets at Pumping Stations – Reduce Likelihood of Arc Flash (electric explosion)

11. Accell Accell is a homogenous, amber colored, neutral, non toxic liquid with no volatile organic compound or living cell. Its is made by Advanced Biocatalytic Corporation (ABC), Irvine, California and Supplied in 55 gallons drums. Accell is a product made of protein surfactant complexes (PSC). Basically, activity of synthetic (unnatural, petrochemical) surfactants are enhanced by tightly bonding them with small stress proteins which are released when baker’s yeast is heat shocked.

12. How Accell works? • Protein Surfactant Complexes as flexible linkers that assist in the solubilization of hydrophobic contaminants. • (PSC) enhances microbial processing by: hydrolysis H2O dissociates to H+ and OH- in the chemical mechanism of organic matter degradation. hydroxylation chemical process of introducing hydroxyl group(OH) for organic matter digestion. • PSC reduces IFT(interfacial tension) thus increases dissolved oxygen uptake • PSC uncouples bio-oxidation from biomass growth by increasing membrane permeability for H+ thus suppressing change in pH and ATP formation (which supplies stored energy for biomass). All living cells require a continual supply of energy for two main purposes: for the biosynthesis of micro and macromolecules, and for the active transport of ions and molecules across cell membranes. The energy derived from the oxidation of nutrients is not used directly but, by means of a complex and long sequence of reactions, it is channelled into a special energy-storage molecule, adenosine triphosphate (ATP). Instead of utilizing the energy from bioxidation for biomass, it applies the energy toward ion and molecule transfer across its membrane thus enhancing digestion of organic matter. • Prevents accumulation of Fats, oil and grease by biocleaning.

14. Accell Claims

15. Documented Success in BP gulf cleanup 2010 • EPA Certified Surface Washing Agent • NSF Certification for treatment of drinking water

16. Quick Tests Laboratory Test • Grab Samples was collected from manhole and tested with Accell. • Result shows a rapid decrease in dissolved sulfide after 10mins of Accell treatment • No detectable sulfide after 30mins

17. 2.Emergency Dosing at Poplar Point • Manual Screen Cleaning when the automated system malfunctions • Employees Were Directed to Leave When H2S Exceeded 10 ppm. • Pumped Accell3 into entering line before entry • Sawtooth action from Odalogger resulted from this dosing Point of dosage

18. Research Methodology • Add Accell3 at a different rates at Main Pumping Station – 0.1, 0.2 and 1.9 ppm. • Take grab samples. • Track Performance at 6 Sites along the East Outfall Sewer. • Measure : ORP (oxidation reduction potential) ;DO (Dissolved oxygen) pH TSS (Total Suspended Solids); VSS (Volatile Suspended Solids) COD (Chemical Oxygen Demand) Nutrient: H2S, NO3-N, NH3, PO4-3

19. Location of Sites Site 1 Site 2 Site 3 Site 4 Site 5 Site 6

20. Dosing Point This is the dosing location of the Accell3 product. (Main PS) This is the first designated sampling location.

21. Siphon Chamber(Site 2) This is the second designated sampling location. All wastewater is collected here before it leaves Main Station.

22. Old Gate House (Site 3) The is the third designated sampling location. (East Outfall Line) The structure is located across the river (1/4 mile) from Main PS. Poplar Point Manhole (Site 4) This is the fourth designated sampling location. (East Outfall Line) -Located a half of a mile from Main Pumping Station.

23. Squeeze Box (Site 5) This is the fifth designated sampling location. Located one mile away from Main Pumping Station. Structure #4 (Site 6) This is the six and final designated sampling location. Located three miles from Main Pumping Station.

24. Typical H2S

25. Average Hydrogen Sulfide Concentration at Six Sites

26. Total Suspended Solid

27. Volatile suspended solids Nitrate 0 GDP 7GDP 10.5 GDP

28. Phosphate 0 GDP 10.5 GDP 7GDP Ammonium 0GDP 7GDP 10.5 GDP

29. ORP H2S gas is produced at -50 to - 250 mV. ORP values reached -300mV during 100+ weather

30. Reduction (good!)

31. Increase (not good)

32. Comparing results to claims

33. Winter study • Maximum H2S of 3 ppm Winter Period 2011 • Temperature range of 50-600 F

34. FATS, OIL & GREASE (FOG) • Cause of Sewer Blockages • Source of H2S • Source of Odor • Major Impact on Operation &Maintenance Costs

35. Latest attempt at FOG studies • Methodology similar to earlier study but with two monitoring points. • Influent stream = screening room • Effluent stream = siphon chamber. • Yet to obtain a conclusive set of data. • Need to have more monitoring sites and longer retention time in sewer line.

36. Study Conclusions Accell3 Results Accell3 Reduce Odors IN Screening Area, Siphon Chamber & Sewer Up to ½ Mile. Treatment Feasible Success Demands Further Study • TSS ,VSS, Phosphate, Nitrate Decreased • COD, Ammonia, TDS increased. • pH and DO - No Change • ORP Was Low – No Impact. • H2S Increasedwith Distance. • Accell3 Mitigated Indoor H2S at Main & Poplar Point pumpstations.

37. Research 2012-2013 Expand Study to Add’l Products/Solutions • ECO2 - Injects Oxygen into Force Mains • STX Catalyts – Inject Catalyts and Peroxide into Force Mains Rapid Oxidation of Sulfonated Organics • Pri-Sci – Add Iron Salts bind Hydrogen Sulfide, Regenerate Iron Salts by Adding Peroxide • Accell – In Combination with Oxygen • Magnesium Hydroxide – Raise pH of Sewerage • Microbes

38. References • APHA-AWWA-WEF, 2005. Standard Methods for the Examination of Water and Wastewater, 21st ed. American Public Health Association, Washington, DC, USA • James CC. Sewers and their construction. Drainage problems of the east (a revised and enlarged of Oritental drainage). Bombay, India: Bennett, Coleman & Company, Ltd., 1917 • Apgar, D.,Witherspoon, J., Easter, C., Bassrai, S., Dillon, C., Torres, E., Bowker, R.P., Corsi, R., Davidson, S., Wolsstenholme, P., Forbes, B., Quigley, C., Ward, M., Joyce, J., Morton, R., Weiss, J., and Stuetz, R., “Minimization of Odor and Corrosion in Collection Systems: Phase 1”, Water Environment Research Foundation, 2007. • Lee and Reucroft, Vapor adsorption on coal and wood based chemically activated carbons (II) adsorption of organic vapors, 1999. • Hatamoto Masashi, TomoMiyauchi, Tomonori Kindaichi, Noriatsu Ozaki, AkiyoshiOhashi. 2011, Dissolved methane oxidation and competition for oxygen in down-flow hanging sponge reactor for post-treatment of anaerobic wastewater treatment, Bioresource Technology, pp1-6 • Fredrik P. Glasser, Jacques Marchand, Eric Samson. “Durability of Concrete –Degradation Phenomena Involving Detrimental Chemical Reactions”, 2007.

39. THANK YOU!!!!!