Frear Publications

60 Publications

Biogas Upgrading on Dairy Digesters

N. Kennedy, G. Yorgey, C. Frear, D. Evans, J. Jensen, C. Kruger. 2015. WSU Fact Sheet FS180E.  This fact sheet is to provide farmers, third party project developers, regulatory agencies, and other stakeholders with a basic understanding of the chemical composition of renewable natural gas, the most appropriate end-use options for dairy digesters, and some of the more common techniques used to clean biogas to RNG quality at dairy digesters. In describing specific technologies, the authors aim to provide information based on the current literature, but not to favor one technology over another. For additional detail or information about other technologies, more comprehensive reports and reviews are available (Krich et al. 2005; Ryckebosch et al. 2011; Jensen 2011).

On-Farm Co-Digestion of Dairy Manure with High-Energy Organics

N. Kennedy, G. Yorgey, C. Frear, C. Kruger 2015. WSU Fact Sheet FS172E. Anaerobic Digestion Systems Series provides research-based information to improve decision-making for incorporating, augmenting, and maintaining anaerobic digestion systems for manures and food by-products. This publication focuses on pre-consumer food wastes that can sustainably be used as substrates for co-digestion with dairy manure and increase the value of co-products. Topics covered include complementary and problematic substrates, the substrate procurement process, regulations, and solutions for co-digestion processing issues.

Anaerobic digestion effluents and processes: the basics

S. M. Mitchell, N. Kennedy, J. Ma, G. Yorgey, C. Kruger,  J. L. Ullman, C. Frear.  Sept 2015. WSU Fact Sheet FS171E. Anaerobic digesters are used worldwide to produce bioenergy and sustainably treat organic waste from municipal, industrial, and agricultural operations. This fact sheet reviews the basic elements of anaerobic digestion and the process used by digesters, including the types of digesters, biochemistry of influents and effluents, laboratory evaluations and optimizing anaerobic digesting through modeling.

Anaerobic Digester Project and System Modifications: An Economic Analysis

Galinato, S., C. Kruger, and C. Frear.  2015. WSU Extension Publication EM090E.  This publication introduces readers to key concerns regarding the profitability of anaerobic digestion systems and includes a discussion of general project costs and potential revenue sources. This publication also examines the potential profitability of three alternative anaerobic digester systems: (a) combined heat and power, which is the baseline system; (b) boiler as a substitute for combined heat and power; and (c) renewable natural gas infrastructure.

The Rationale for Recovery of Phosphorus and Nitrogen from Dairy Manure

Yorgey, G., C. Frear, C. Kruger, T. Zimmerman. 2014. WSU Extension Fact Sheet FS136E.

Dairy Waste Biorefinery

Kennedy, N., C. Frear, M. Garcia-Perez, C. Kruger, and S. Chen. 2013. Concept illustration and description.

Organic Waste Biorefinery

Kennedy, N., C. Frear, M. Garcia-Perez, C. Kruger, and S. Chen. 2013. Concept illustration and description.

Review of emerging nutrient recovery technologies for farm-based anaerobic digesters and other renewable energy systems

Prepared for Innovation Center for US Dairy by Jingwei Ma, Nick Kennedy, Georgine Yorgey and Craig Frear.  Nov 2013.  Washington State University.

The effects of the antibiotics ampicillin, florfenicol, sulfamethazine, and tylosin on biogas production and their degradation efficiency during anaerobic digestion

Mitchell, S., J. Ullman, A. Teel, R. Watts, C. Frear.  Bioresource Technology Volume 149, December 2013, Pages 244–252.

Anaerobic Digestion (AD) Technology Certificate Program

Website highlighting a WSU – Bellingham Technical College partnership to offer training for anaerobic digestion technicians.  Full curriculum, videos and more available online.

Efficient Use of Algal Biomass Residues for Biopower Production with Nutrient Recycle: Final Project Report

Jarvis, E. R. Davis, C. Frear. Aug 2013.

Anaerobic Digestion Systems: Integrating emerging technologies to improve environmental and economic impact

C. Frear, C.Kruger, H. Collins, M. Garcia-Perez, C. Stockle, R. Shumway, G. Astill, T. Ewing, N. Kennedy, T. Khalil, and G. Yorgey. July 2013. Academic Poster.

2011-2013 Anaerobic Digestion Related R&D Research Summary for WSU ARC/WSDA Appendix-A Funds

Frear, C, M. Garcia-Perez, C. Kruger, S. Chen. 2013.

Methanosarcina domination in anaerobic sequencing batch reactor at short hydraulic retention time

J. Ma, B. Zhao, C. Frear, Q. Zhao, L. Yu, X. Li, S. Chen. June 2013.Bioresource Technology Volume 137, June 2013, Pages 41–50.

Anaerobic Digestion: Beyond Waste Management

May 2013. CSANR produced a 7.5 minute video showing how state-of-the-art anaerobic digestion systems can offer multiple benefits to society.

Anaerobic Digestion of Algal Biomass Residues with Nutrient Recycle

April 2013. Zhao, B., J. Ma, Q. Zhao, and C. Frear.  WSU subcontract work on Department of Energy Project 22902.

A simple methodology for rate-limiting step determination for anaerobic digestion of complex substrates and effect of microbial community ratio

J. Ma, C. Frear, Z. Wang, L. Yu, Q. Zhao, X. Li, S. Chen. Bioresource Technology.  Volume 134, April 2013, Pages 391–395.

Kinetics of psychrophilic anaerobic sequencing batch reactor treating flushed dairy manure

J. Ma, L. Yu, C. Frear, Q. Zhao, X. Li, S. Chen. Bioresource Technology.  Volume 131, March 2013, Pages 6–12.

Experimental and modeling study of a two-stage pilot scale high solid anaerobic digester system

L. Yu, Q. Zhao, J. Ma, C. Frear, S. Chen. Bioresource Technology. Volume 124, November 2012, Pages 8–17.

Renewable Natural Gas Feasibility for Qualco Energy

May 2012. Coppedge, B., G. Coppedge, D. Evans, J. Jensen, K. Scanlan, B. Scanlan, P. Weisberg, and C. Frear. An anaerobic digester case study for alternative outtake markets. A report to Washington State Department of Commerce.

Renewable Natural Gas and Nutrient Recovery Feasibility for DeRuyter Dairy

May 2012. Coppedge, B., G. Coppedge, D. Evans, J. Jensen, K. Scanlan, B. Scanlan, P. Weisberg and C. Frear. An anaerobic digester case study for alternative outtake markets and remediation of nutrient loading concerns within the region. A report to Washington State Department of Commerce.

Anaerobic Digester Technician video – Bellingham Technical College

WSU and Bellingham Technical College produced this video as a part of their grant-funded Anaerobic Digestion Technician certificate program. The video explains the technical aspects of operating and maintaining an anaerobic digester.

Two novel floor-scale anaerobic digester systems for processing food waste. Part 1: Multi-reactor, liquid recycle system for high solids. Part 2: Moderate solids system.

Frear, C., Ewing, T., Yu, L., Ma, J., and Chen, S. 2012. Olympia, WA. Washington State Department of Ecology.

Estimating greenhouse gas emissions from soil following liquid manure applications using a unit response curve method

G. Wang, S. Chen, C. Frear. Geoderma. Volume 170, 15 January 2012, Pages 295–304.

Extracting valuable energy, carbon and nutrient resources from organic waste

WSU scientists have conducted extensive research on Anaerobic Digestion (AD) as a technology for recovery of methane (energy), stable carbon, and nutrients from organic wastes such as manure, food processing wastes and the organic fraction of municipal solid wastes (OFMSW). Our research has evaluated the technical and economic performance of commercially available systems, developed improved AD reactors, and commercialized WSU patented nutrient recovery technology. This webinar, presented by CSANR director Chad Kruger and CSANR scientist Craig Frear, will provide an update on the latest results from the WSU Climate Friendly Farming Project’s AD research.

« Older Frear Publications