Improvements to biogas production using micronutrients, operational methodologies, and biogas processing equipment to enable pipeline injection of biomethane
Generating best practices for operating food waste digesters to maximize biogas yield
Biogas Energy Inc.
Recipient
Sebastopol, CA
Recipient Location
2nd
Senate District
2nd
Assembly District
$414,973
Amount Spent
Completed
Project Status
Project Result
Biomethane potential for over 25 digester feedstocks were evaluated at the lab-scale to analyze the composition and volume of biogas produced. Many feedstocks, some unconventional, were introduced to the commercial-scale digester and their effect on digester performance and biogas output was monitored. Some feedstocks previously thought to harm digester operation exceeded expectations. For example, olive waste was expected to inhibit biogas production due to its high sodium content, however, it proved to be an excellent feedstock with little adverse effects on digester performance. Results of the study were compiled in order to produce a best practices recommendations in the final report.
The Issue
There are over a dozen anaerobic digester facilities in California which convert organic waste into biogas to produce renewable heat, power, and vehicle fuel. The number of facilities is expected grow substantially in the near future as California aims to meet its ambitious waste diversion, greenhouse gas reduction, and renewable energy goals. Despite the rapid growth of this industry many aspects of the anaerobic digestion process are not well understood causing digesters to operate sub-optimally. There is a need to better understand the anaerobic digestion process, including the effect of individual feedstocks on overall performance.
Project Innovation
This project conducted a study on operation of the anaerobic digestion process; improving biogas production through the use of micronutrients, co-digestion efficiencies, feedstock analysis, and operational modifications. The project leveraged existing anaerobic digester infrastructure at North State Rendering to perform detailed analysis of the biology of the digesters at the site. The project simultaneously performed laboratory experiments at CSU Chico using various feedstocks and digestate harvested from the commercial digester. Detailed analysis of the effects of feedstock supply, micronutrient management, and operational improvements were performed by the team with the aim of generating a set of best practices for the optimization of biogas production.
Project Benefits
This project led to technological advancements by demonstrating a system with increased biogas production per unit of feedstock, improved quality of biogas production, and lower costs for system operation, which improves the economics of organic waste conversion to energy, compared to conventional practices.
Affordability
By understanding the effect of different feedstocks on digester performance, the results of this project were used to optimally select digester feedstocks and subsequently lower the cost (per standard cubic foot produced) of biogas production. The project provides optimization recommendations that could increase biogas production at existing digesters by up to 10 percent.
Environmental Sustainability
Environmental benefits include an increase in biogas capture, increased diversion of landfill waste, and contributions to the reduction of fossil fuel use in the state.
Key Project Members
Brian Gannon
Subrecipients
CytoCulture International, Inc
Match Partners
North State Rendering Co. Inc
Springboard Biodiesel LLC
Biogas Energy Inc.
