A Review of Available Resources on Anaerobic Digestion Technologies

Anaerobic digestion of manures provides multiple environmental benefits for animal feeding operations including odor reduction, green house gas emission reduction, and production of a renewable energy source. This paper provides an overview of information sources available in the United States regarding anaerobic digestion of manures. Selection and implementation of an optimal anaerobic digestion system for a given farm requires significant research regarding digester type, biogas production potential, biogas collection and handling, construction cost estimates, and operation and maintenance cost estimates. Practical information concerning anaerobic digestion is dispersed through a number of sources in the U. S. Information sources in this review include items from the federal and state government agencies, land grant universities, and non-profit organizations. The reviewed items provide information related to methane recovery technologies on U.S. concentrated animal feeding operations, economics of biogas production for on-farm heating, case studies of U.S. animal manure digesters, and various other anaerobic digestion resources. A concise review of available US information sources regarding the anaerobic digestion of animal manures is provided to assist in the decision making process concerning selection and implementation of manure anaerobic digesters

Anaerobic Digestion System Selection for Croatian Swine Manures

Interest in the anaerobic digestion (AD) of swine manures and slaughter waste continues to increase due to the potential to produce renewable energy in the form of biogas and due to the expanding market for carbon credits around the world. This paper provides an analysis of the anaerobic digestion types and operational schemes that are best suited to Croatian swine production. In addition, it proposes a methodology to optimize system selection and design by predicting biogas production quantity and quality based on the use of biochemical methane potential (BMP) assays followed by the use of pilot-scale reactors to make final system selections and estimate system hydraulic retention times (HRT) for the selected system design. A review of reactor configurations that are promising for swine manure and slaughter waste digestion suggests that a mesophilic, continuously fed AD system be investigated to digest a mix of Croatian large-scale swine manure and slaughter waste

A Review of Available Resources on Anaerobic Digestion Technologies

Anaerobic digestion of manures provides multiple environmental benefits for animal feeding operations including odor reduction, green house gas emission reduction, and production of a renewable energy source. This paper provides an overview of information sources available in the United States regarding anaerobic digestion of manures. Selection and implementation of an optimal anaerobic digestion system for a given farm requires significant research regarding digester type, biogas production potential, biogas collection and handling, construction cost estimates, and operation and maintenance cost estimates. Practical information concerning anaerobic digestion is dispersed through a number of sources in the U. S. Information sources in this review include items from the federal and state government agencies, land grant universities, and non-profit organizations. The reviewed items provide information related to methane recovery technologies on U.S. concentrated animal feeding operations, economics of biogas production for on-farm heating, case studies of U.S. animal manure digesters, and various other anaerobic digestion resources. A concise review of available US information sources regarding the anaerobic digestion of animal manures is provided to assist in the decision making process concerning selection and implementation of manure anaerobic digesters.</p

Anaerobic Digestion System Selection for Croatian Swine Manures

Interest in the anaerobic digestion (AD) of swine manures and slaughter waste continues to increase due to the potential to produce renewable energy in the form of biogas and due to the expanding market for carbon credits around the world. This paper provides an analysis of the anaerobic digestion types and operational schemes that are best suited to Croatian swine production. In addition, it proposes a methodology to optimize system selection and design by predicting biogas production quantity and quality based on the use of biochemical methane potential (BMP) assays followed by the use of pilot-scale reactors to make final system selections and estimate system hydraulic retention times (HRT) for the selected system design. A review of reactor configurations that are promising for swine manure and slaughter waste digestion suggests that a mesophilic, continuously fed AD system be investigated to digest a mix of Croatian large-scale swine manure and slaughter waste.</p

Use of Biochemical Methane Potential (BMP) Assays for Predicting and Enhancing Anaerobic Digester Performance

A Biochemical Methane Potential (BMP) assay provides a measure of the anaerobic digestibility of a given substrate. The use of BMPs provides a relatively inexpensive and repeatable method to make relative comparisons of the anaerobic digestibility and potential biogas production between various substrates. Biochemical Methane Potentials can be used to determine the amount of organic carbon in a given material that can be anaerobically converted to methane and to evaluate potential biogas production efficiency of the anaerobic process on a given material. The information provided by BMPs is valuable when evaluating potential anaerobic substrates and for optimizing the design and operation of an anaerobic digester. This paper describes the BMP assay procedure used in the Agricultural Waste Management Laboratory at Iowa State University for quantifying both biogas production and methane content and it describes how the results can be used.</p

Development of a Wireless Sensor Network to Quantify Hydrogen Sulfide Concentrations in Swine Housing

Previous research by our team to develop a wireless hydrogen sulfide (H2S) detection system for use in swine housing indicate a multi-point detection system is needed to characterize in-house H2S concentrations both spatially and temporally during slurry agitation. Pulsed fluorescence H2S analyzers, while highly accurate at H2S concentrations less than 20 ppm, require asynchronous sampling to accommodate multiple measurement points with a single analyzer. Additionally, pulsed fluorescence H2S analyzers are not designed to measure the high H2S concentrations associated with burst releases during deep-pit swine manure agitation. The dynamic nature of the environment necessitates simultaneous sampling of multiple points with a sensor that can respond to very high (100 – 500 ppm) H2S concentrations. This can be accomplished through the use of electrochemical sensors that have demonstrated the ability to perform similarly to pulsed fluorescence at high concentrations. The objective of this project was to develop a wireless H2S sensor network that can be used to characterize the spatial distribution of H2S that workers and swine in pork production facilities are exposed to in different facility types during different operating conditions. The wireless H2S sensor network developed in this project was designed to meet the following operational criteria: a) less than 5% sensor drift per 1000 ppm-hours, b) up to 50 m range, c) data collection interval less than 90 seconds, and e) H2S detection range of 0-500 ppm.This is an ASABE Meeting Presentation, Paper No. 096640.</p