Colorado Agricultural Experiment Station
Active Projects 2013

Note: A NEW project—initiated within last year—might not have an annual report, publications, or outcomes/impact.
Project: COL00696 Department: Civil & Environmental Engineering  
PIs: Sharvelle, SE
Title: Pilot Scale Demonstration of a Multi-Stage Anaerobic Digester for Generation of Energy from Dry Lot Manure and Design of Full Scale System
Begin Date: 07/01/2011 Term Date: 06/30/2013 Most recent project status: Terminated
Objectives: The objective of this work is to test a trailer mounted pilot scale multi-stage anaerobic digester capable of generating methane from dry manure and to design a full scale system. Funds received from AES will enhance process monitoring of the pilot scale multi-stage anaerobic digester (MSAD). Results from operation of the MSAD in addition to survey data collected from dairy and feedlot producers will be applied to develop an optimized deign for the full scale MSAD. The project output will be the design of a full scale MSAD which meets producer needs and will be ready for commercialization.
Approach: This project will consist of two tasks; monitoring a pilot scale demonstration MSAD and conducting surveys at dairies and feedlots to determine the optimal design for the full scale system. Operation of Pilot Scale MSAD - The trailer mounted MSAD is currently under fabrication and will be depolyed in June of 2011. Funds are available for monitoring of basic parameters including total solids, volatile solids, chemical oxygen demand (COD), and methane. AES funds will be applied to also monitor specific volatile fatty acids (VFAs) including acetic acid, propanoic acid, butanoic acid, and valeric acid (measured by gas chromatography). Identification of VFAs reveals information on the efficiency of hydrolysis, which occurs in the LBR. MSAD process efficiency hinges on the efficiency of hydrolysis. Therefore, the ability to monitor VFAs is critical for process optimization. Results from pilot scale operation of the MSAD will guide design of the full scale system. Survey Dairy and Feedlot Producers - Dr. Sharvelle's research group has already collected some general information about management practices typical of Colorado dairies, i.e. whether dry scrape, concrete scrape, or flushing of manure are performed. Far more detailed information is now required to design the full scale MSAD. The following information will be gathered from dairy and feedlot producers. 1. Frequency of dry lot manure collection (seasonal differences?) 2. Application of straw or other material prior to collection (seasonal differences?) 3. Type of equipment used for dry scrape manure collection 4. Modifications to the MSAD design to integrate with existing manure collection methods 5. Willingness to adopt MSAD based on current design.
Keywords: anaerobic digestion dry digestion manure management methane waste conversion to energy biogas animal feeding operation