Transformation and Agronomic Use of Nutrients From Digester Effluent

Table of Contents

Anaerobic Digestion Nutrient Transformations

Anaerobic digestion (AD) is the process in which organic compounds are broken down by naturally occurring bacteria, including methanogenic microorganisms under oxygen free conditions, transforming organic matter into biogas (methane (CH4), carbon dioxide (CO2), water vapor, ammonia, and hydrogen sulfide) (Dugba and Zhang, 1999; AgSTAR, 2010b). The end products of this process include biogas, a renewable …

Cayuga County Manure Digester Virtual Tour

livestock and poultry environmental learning center logo with cow, pig, and chicken sillhouettes over a map of the U.S. with three circling arrows

Anaerobic digestion is a manure treatment system that produces biogas. There are many benefits of digestion such as reductions in: odor, pathogens, and greenhouse gases (climate change). Producing biogas from manure yields useful by-products.  The economics of digestion are dependent on state energy policies and co-digestion of off-farm wastes to generate revenue.

Cayuga County Regional Digester (New York)

This virtual tour highlights the Cayuga County Soil & Water Conservation District regional digester. This facility receives …

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, …

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 …

Grass To Gas project

What is it?

The Grass-to-gas project is a 5-year, USDA-funded project that carries out research, extension, and education programs aimed at developing new approaches to Anaerobic Digestion that are economically beneficial to farmers and ecologically beneficial to farms.

Participants:

The project is led by Iowa State University and Penn State University, with a team of partner farmers and companies all working together to grow this opportunity.

Features:

Demonstration Farms, where perennial grass production, cover crops, and their use in biogas …

Anaerobic Digestion

Bioenergy Curriculum graphic

This Anaerobic Digestion module is part of the Biomass Energy Training Curriculum, 13 modules developed through a Southern SARE grant and collaboration between Tennessee State University, the University of Tennessee, eXtension.org, and USDA-Rural Development. While it is written as a training guide for TN producers, much of the information is applicable throughout the Southeastern US region.

This curriculum is designed to increase the knowledge base of extension agents and local officials on biomass energy; so that they may, in

Introduction to Processing Feedstocks into Biofuels

Processing Biodiesel
From feedstock to fuel. Photos: D.Ciolkosz, M.Szala, Biodiesel Ed at U Idah. CC license

Biomass is transformed into solid & liquid fuels, gas, electricity and heat using a variety of processing methods and equipment.

TOPICS

Introduction

One of the main barriers to a successful biomass energy industry is the simple fact that most raw biomass is not immediately useful as an …

How Sustainable are Your Farm Energy Systems?

Learn about sustainability indicators used to gauge and evaluate a farm’s progress toward energy sustainability.

Solar installation at Harlow Farm, Westminster, VT. Photo: Susan Harlow

Table of Contents

What Is a Sustainability Indicator?

Sustainability indicators are measurable or observable features that can be used to test principles and criteria of sustainability. Sustainability indicators could include quantifiable measures of resource use efficiency, energy, food security, land use impacts

Anaerobic Digestion and Biogas

 

Farm Energy IQ logo

This Biogas module provides reasonable expectations for investing in on-farm bio-digesters to convert animal waste to process heat and/or electricity. Learn how to calculate the number of animals needed to build a cost effective system.

Link to all of the Northeast Farm Energy IQ Curriculum, developed by Extension specialists from Penn State, Rutgers and University of Vermont.

This is part of the On Farm Energy Production Curriculum Series: 

Bioenergy Feedstock Production | Biodiesel and SVO | Biogas | Wood

Conversion Processes for Biofuel Production – Table of Contents

The variety of biofuel processing methods and equipment is remarkable, allowing us to transform energy feedstocks into useful solid fuels, liquid fuels, gases, electricity, heat or mechanical work. One of the main barriers to a successful biomass energy industry is the simple fact that most raw biomass is not immediately useful as an energy source. Biofuel crops must be processed in one way or another before they can be a valuable source of energy.

Biodiesel reactor Williamson
Biodiesel Reactor, State Line Farm, Shaftsbury,VT.