Grass to Gas Winter Webinar Series 2023-24

Innovating a New Future for Anaerobic Digestion

Join us for monthly webinars on the emerging science that sits at the juncture of Renewable Natural Gas, Anaerobic Digestion, and Regenerative Agriculture.

Learn from thought leaders who are expanding what is known about transforming our agricultural sector in terms of its energy, economic, and ecological performance.

Engage in discussion about new discoveries about integrating biogas and regenerative agriculture together into the rural economy.

Who Should Attend?

All are welcome!  These webinars will be presenting new and emerging research in …

Grass To Gas Anaerobic Digestion Q&A

This page lists questions and answers from the C-Change GrassToGas project’s PA Extension newsletter.  To be added to the newsletter mailing list, contact GrassToGas@psu.edu.

1. Question: Is switchgrass a good feedstock for biogas digesters?

Answer: Not usually. Anaerobic digestion involves microscopic organisms that eat energy-rich components such as sugars. Lignocellulosic biomass, such as switchgrass, contains sugars, but is structured in a way that specifically prevents easy access to its energy-rich components. Because of the limited accessibility to the energy-rich …

Farm Energy Anaerobic Digestion and Biogas


Contents:barn

Articles and Fact Sheets


Processing Biomass Into Biogas


Tables Of Contents

Anaerobic Digestion of Animal Manures: Understanding the Basic Processes

Anaerobic Digesters and Biogas Safety

When manure is anaerobically digested, the biogas produced is primarily composed of methane and carbon dioxide, with lesser amounts of hydrogen sulfide, ammonia, and other gases. Each of these gases has safety issues. Overall, biogas risks include explosion, asphyxiation, disease, and hydrogen sulfide poisoning.

Image: US Municipal Supply Company.

Extreme caution is necessary when working with biogas. Adequate ventilation, appropriate precautions, good work practices, engineering controls, and adequate personal protective equipment will minimize the dangers associated with biogas. Wherever possible, …

Biogas Utilization and Cleanup

Introduction

Biogas generated from anaerobic digestion processes is a clean and environmentally friendly renewable fuel. But it is important to clean, or upgrade, biogas before using it to increase its heating value and to make it useable in some gas appliances such as engines and boilers.

Biogas Utilization

While most large farms use their biogas for heat and power, it is worthwhile to consider all the options before deciding which path to take, including direct sale of biogas to an …

Uses of Solids and By-Products of Anaerobic Digestion

Anaerobic Digestate Pile at Scenic View Dairy in Fennville, MI
Anaerobic Digestate Pile, Scenic View Dairy, MI. Photo: M.C. Gould, MSU Extension

Anaerobic digestion generates a wide range of byproducts that farmers can use in their farming operations or sell. Beyond biogas used to generate electricity or as fuel, and liquids used for fertilizer or soil amendments, there are solid byproducts, which have a wide range of applications.

Table of Contents:

Environmental Benefits of Anaerobic Digestion

The manure handling system of any farm is made up of many different components, each with a different function and purpose. An anaerobic digester, although only one component of the system, can greatly improve the environmental performance and efficiency of the overall system. The main effect of anaerobic digestion is conversion of organic matter to biogas. This conversion has many potentially beneficial environmental and management side effects.

Odor reduction

By removing organic matter, the digester reduces the organic matter-loading and …

Pathogen Reduction in Anaerobic Digestion of Manure

Benefits of Anaerobic Digestion of Manure in Reducing Pathogens

Manure is a biologically active material that hosts and supports many microorganisms and thus can seldom be considered “pathogen free.” Certain manure handling techniques and methods, however, can limit the production and multiplication of such pathogens. Common sense must be used when making manure handling decisions. Pathogens are microbes such as bacteria, viruses, protozoa, and other organisms that cause disease. These pathogens persist commonly in animal manures. For more information …

Types of Anaerobic Digesters


Table Of Contents
Passive Systems
Low Rate Systems
High Rate Systems
Contributors To This Article

All anaerobic digesters perform the same basic function. They hold manure in the absence of oxygen and maintain the proper conditions for methane forming microorganisms to grow. There is a wide variety of anaerobic digesters, each performing this basic function in a subtly different way. Seven of the most common digesters are described in this article. Construction and material handling techniques can vary greatly within …