Advances in Leachate Management Research to Address Emerging Concerns UV Interference Stephanie C. Bolyard, PhD Research and Scholarship Program Manager April 5, 2017 NC SWANA 2017 Spring Conference 

Emerging Concerns Near Term Longer Term Color Emerging contaminants UV transmittance (POTW) Nutrients Refractory Dissolved Organic Nitrogen (rDON) Total Dissolved Solids/ Chlorides Refractory COD Arsenic Emerging contaminants Boron, PFCs, future unknowns Pharmaceutical and Personal Care Products (PPCPs) Nano-particles Tritium Omparison to1 min Source: EREF Summit on Leachate Management

Inhibition of UV Transmittance In 2010 there was an estimated 7.1 billion gallons of leachate generated Leachate disposal to POTWs can be a cost effective disposal option But organics in leachate can interfere with downstream UV disinfection Omparison to1 min

MSW Landfill discharged 5 tons of nitrogen in one month Nutrient Management Leachate has a high concentration of nitrogen requiring treatment. Existing technologies utilize biological treatment to oxidize ammonia-N to N2. Numeric Nutrient Criteria may lower the total nitrogen and phosphorus limits. Omparison to1 min MSW Landfill discharged 5 tons of nitrogen in one month

Leachate Management Research Development of a Strategy for the Treatment of Landfill Leachates (Virginia Tech) Approaches to Mitigation of Landfill Leachate‐Induced UV Transmittance Impacts (Montclair State) Developing Strategies to Recover and Treat Nutrients in the Landfill Leachate (University of Utah and University of Central Florida) Omparison to1 min

Minimizing Inhibition via Pre-Treatment Knowledge Gaps What leachate characteristics cause UV interference? Suspect small size organics (e.g. humics) may be the culprit How does variation in leachate characteristics affect UV interference? Leachate from different landfills will vary and influence the extent of interference How can leachate be treated to remove constituents causing UV interference? Develop a recommended pre-treatment strategy Omparison to1 min

UV absorbance is not the same as color! Initial Leachate Characterization Characterized particulate size fractionation and compared against: Micro-filtration (0.1 µm – 1 µm) Ultra-filtration (1 kDa-100 kDa) Nanofiltration (200 Da-1 kDa) Reverse Osmosis (< 200 Da) UV absorbance is not the same as color! Salts and Metal Ions Virus Bacteria Omparison to1 min 500Da 1kDa 3kDa 5kDa 1kDa 30kDa 100kDa .22um .45um 1.5um Raw

Size Fractionation Observations Organic carbon particulates in leachate are very small Less than 3,000 kDa (bacteria) Most less than 100 kDa (viruses) Suggests physical/chemical methods of treatment (e.g. filtration, coagulation) will NOT work well Some success potentially with nanofiltration More success with reverse osmosis Omparison to1 min

UV Transmittance for Different Leachates Leachate volumes as low as 1 – 4% of total volume treated by a POTW can significantly hinder UV disinfection (Zhao) Field studies by Bolyard and Reinhart, (2015) found that a leachate contribution of 0.59-1.1% can interfere with UV disinfection. Omparison to1 min

Oxidation (Fenton’s Reagent) Treatment Methods Evaluated Treatment Process Effective? Coagulation NO Adsorption (PAC) Moderately Ion Exchange Ultrafiltration For Humics Reverse Osmosis YES Oxidation (Fenton’s Reagent) Anaerobic MBR & SBR Omparison to1 min

Leachates Sampled The leachate samples were collected from on-site municipal solid waste landfill leachate treatment facilities from PA-1: (Active & Inactive) PA-2: (closed in 2011) PA-3: (closed in 2003) NH: (Active) "Treated leachates" were the samples collected from sequencing batch reactor (SBR) Omparison to1 min

SBR Treatment Effect Omparison to1 min SBR treatment was successfully at removing DOC but UV absorbance still a challenge.

Pretreatment and Co-Treatment Omparison to1 min SBR Only

Combined Treatment Omparison to1 min

Reducing UV-quenching substances in landfill leachate. Submerged Anaerobic Membrane Bioreactor (AnMBR) with sequential thermophilic (55°C) and mesophilic digestion (37°C) (~7 months of treatment). Both digestion processes work together to degrade different aromatic compounds responsible for UV interference Omparison to1 min

The absorbance decreased considerably following the AnMBR stage Results Young Leachate Mature Leachate Omparison to1 min The absorbance decreased considerably following the AnMBR stage Long-term removal of over 60% of the total organic carbon from raw landfill leachates was observed using this two stage strategy, resulting in a reduction in UV absorbance by over 40%.

Integrated “Recovery and Removal” Current paradigm Anaerobic digester reject water and landfill leachate are two concentrated waste streams rich in N, P and C, and handled separately. The current management schemes entirely focus on removal which can be limited by the presence of recalcitrant compounds and inhibitory concentrations. Proposed paradigm Omparison to1 min

Step 1: Nutrient recovery at different pHs Experimental Approach Digester Reject Water Step 1: Nutrient recovery at different pHs + Leachate Step 2: Granular activated sludge process to remove carbon. Unlike in flocculated activated sludge processes, dense granules will be able to tackle toxics: Alternative: Use anaerobic process to recover carbon Omparison to1 min Step 3: Partial nitrification coupled with anaerobic ammonia oxidation to remove remaining nitrogen

Struvite Precipitation Preliminary Results Initial Concentration (mg/L) Struvite Precipitation Phosphorus removal 75% 9.21 mg/L Ammonia removal 16% 474 mg/L Biological treatment Granular reactor COD removal 42% 542 mg/L Ammonia removal 15% 374 mg/L Phosphorus removal 50% 2.30 mg/L Single-stage partial nitrification/Anammox reactor Ammonia removal 25% 318 mg/L Omparison to1 min

Conclusions On‐site leachate treatment combined with co‐treatment of sewage at POTWs is still necessary to address the UV transmittance challenges at POTWs. Three on‐site treatment trains achieved an effluent UVT ≥ 65% when coupled with treatment at a POTW SBR  coagulation  PAC adsorption SBR  coagulation  Fenton SBR  Fenton treatment Omparison to1 min

Conclusions Nutrient Recovery has the potential to be a revenue source and a means to improve the effectiveness of subsequent biological treatment.

Acknowledgements Yang Deng - Montclair State Ramesh Goel - University of Utah John Novak - Virginia Tech Amy Pruden - Virginia Tech Debra Reinhart - University of Central Florida Omparison to1 min

Questions Stephanie C. Bolyard, PhD sbolyard@erefdn.org www.erefdn.org 2017 EREF Leachate Summit at WasteExpo May 8, 2017 New Orleans, LA The EREF Summit will bring together practicing engineers, academics, industry professionals, government personnel, and policy makers for in-depth discussions on topics related to landfill leachate treatment and management. https://erefdn.org/event/2017-eref-leachate-summit-wasteexpo/

Nutrient Recovery Potential Landfill Solid waste Complex blend of contaminants Current approaches rely on “removal” Omparison to1 min Leachate Significant concentration of nitrogen and carbon How can we recover and treat using innovative approaches?