Advancing Anaerobic Digestion of Wastewater Solids and Food Waste for Energy and Resource Recovery: Science and Solutions-A Framework for the Practice of Co-Digestion
Wednesday October 25 and Thursday October 26, 2017
Mary Gates Learning Center
United Way, 701 North Fairfax Drive
Alexandria, VA 22314

Water Environment & Reuse Foundation (WE&RF), with support from the Water Research Foundation (WaterRF) and the Water Environment Federation (WEF), held a National Science Foundation (NSF) funded workshop that provided an overview of recent research findings on co-digestion of organic wastes (such as food waste) with wastewater solids. The invited participants discussed, contributed and identified best practices currently used by water resource recovery facilities from their experience with co-digestion. 

This Workshop was designed to promote dialog between researchers, experts, and the community of practitioners of co-digestion. The recommendations and outcome of the Workshop will be used to develop a Framework of Practice that will be published by WE&RF and WaterRF and then integrated with the WEF community of practice publications for wastewater/resource recovery professionals.

Agenda (PDF)


Advancing Anaerobic Digestion of Wastewater Solids and Food Waste for Energy and Resource Recovery: Science and Solutions-A Framework for the Practice of Co-Digestion
Wednesday, October 25 – Thursday, October 26

Sponsored by:                  Location 
National Science Foundation
Water Environment & Reuse Foundation
Water Research Foundation
Water Environment Federation
  Mary Gates Learning Center
United Way, 701 North Fairfax Drive
Alexandria, VA 22314

For more information:
Lauren Fillmore

Day 1 
7:30 am Coffee, nametags, networking   
8:00 - 8:30 am Main Room Plenary
Welcome and brief introductions
Meeting objectives and logistics
Lauren Fillmore
Rob Greenwood
Ross Strategic
  Recent Advances in Understanding Anaerobic Digestion Processes 
8:30 am  WERF Research into the Operational Impacts of Co-Digestion
Results of a two-phase survey of operational data from utilities currently performing pilot/full-scale co-digestion will be presented. Researchers determined the operational effects of various types of wastes on the system and final product management as well as determined the overall benefit of various types of wastes.
Matt Van Horne
Hazen and Sawyer
8:50 am 
Impact of Co-digestion on Treatment Plant Operations – 5 Plant Experience 
Mark Greene, Ph.D., OBG evaluated co-digestion facility design, performance data, and operation and maintenance issues at five WRRFs in New York, Texas, and California. Laboratory-scale biomethane potential tests on wastewater solids and organic waste were used to evaluate the impacts of co-digestion on methane production, sludge production, and nitrogen and phosphorus concentrations in recycle streams.

Mark Greene
9:10 am  Understanding Impacts of Co-Digestion:  Digester Chemistry, Gas Production, Dewaterability, Solids Production, Cake Quality, and Economics 
Matt Higgins, Ph.D., Bucknell University developed an analytical approach to understand and predict the broad array of impacts of co-digestion, including effects on digester chemistry, digestate rheology and subsequent volume expansion, dewatering, and cake quality/odors. The effects on digester chemistry were predicted well with stoichiometry.
Matt Higgins
Bucknell University
9:35 am Anaerobic Digester Feeding Pattern Drives Long-chain Fatty Acid (LCFA) Bioconversion Kinetics and Syntrophic Community Structure 
Ryan Ziels, University of British Columbia, will present findings from experimental anaerobic codigesters fed with dairy cattle manure and oleate (C18:1) with either a pulse-fed or continuous-fed regime. Pulse-feeding LCFA during anaerobic codigestion selected for higher microbial bioconversion kinetics and functional stability, which were related to changes in the fine-scale syntrophic community structure.
Ryan Ziels
University of British Columbia
10:00 am  Break   
10:15 am Anaerobic Communities
Dr. Kartik Chandran, Columbia University, will summarize his research providing a better mechanistic understanding of the microbial communities, carbon conversion pathways and kinetics of anaerobic carbon conversion processes using high-throughput, next generation sequencing and analysis techniques which include metagenomics (community structure and potential pathways).
Kartik Chandran
Columbia University
  Interactive Participant Breakout Discussions
10:45 am
Breakout Session 1: Wastes Suitable for Co-digestion – Type, preprocessing, and availability
Breakout Session 2: Waste Receiving Practices and Program Attributes
12:15 pm Lunch  
1:15 pm
Breakout Session 3: Critical Feedstock Characterization
Breakout Session 4: Operational Strategies for Optimal Performance
3:00 pm Break  
3:15 pm
Breakout Session 5: Side Effects on Treatment and Residuals Operations
Breakout Session 6: Biogas-related Issues, Energy Recovery Options and Issues 
4:30 pm Plenary Report Out: Recommendations  
5:00 pm Wrap up Day 1  
Day 2 
7:30 am Coffee, nametags, networking  
8:00 am Main Room Plenary
Meeting objectives and instructions
Rob Greenwood
Ross Strategic
Breakout Sessions  
8:15 am
Breakout Session 7: Return on Investment Considerations
Breakout Session 8: Co-digestion Facility Design and Other Requirements
10:15 Break  
10:30 am Continued Dialog and Recommendation Summary  
12:15 pm Lunch  
1:15 pm Plenary Report Out: Recommendations  
2:15 pm Knowledge Gaps and Research to Advance Practice of Co-Digestion  
3:00 pm Wrap up Day 2