Advanced Manure Management for Small Dairy Farms

EPA Contract Number: EPD08018
Title: Advanced Manure Management for Small Dairy Farms
Investigators: Roberts, T. Guy
Small Business: Avatar Alternative Energy Inc. d.b.a. Avatar Energy, LLC
EPA Contact: Richards, April
Phase: I
Project Period: March 1, 2008 through August 31, 2008
Project Amount: $70,000
RFA: Small Business Innovation Research (SBIR) - Phase I (2008) RFA Text |  Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , SBIR - Animal Waste and Waste to Energy


This proposed project is for the experimental operation and performance review of a pilot-scale anaerobic digester and effluent treatment system for small dairy farms. This would be one of the first digesters built on a dairy farm with a herd size of 50-100 heads. Although digesters are considered to be a valuable addition to a farm’s manure management strategy, several sources have stated that farms of this size are incapable of feasibly maintaining anaerobic digesters. The principal barrier to implementation of anaerobic digesters is generally considered to be the cost of project-specific engineering and large-scale construction. The digester in development by Avatar Alternative Energy addresses these concerns with the following design features: The digester is modular and can be assembled by a small crew utilizing farm equipment. The digester is a moveable asset on the farm, replacing poured concrete vessels for larger-diameter fiberglass pipe sections, which can be disassembled for maintenance and/or relocation on the farm or resale. Due to the modular nature of the equipment, the scale of the digester can follow changes to the farm’s herd size. Avatar’s pilot digester is based on the robust plug flow architecture and includes specific design features to enable inexpensive maintenance and straightforward operation. Avatar also has developed a low-cost solids separator to separate the digested manure into liquid and solid fractions. The manure is treated through a series of steps that will significantly reduce nitrogen and phosphorus and will ultimately be used to support greenhouse activities.

Supplemental Keywords:

small business, SBIR, EPA, anaerobic digester, animal waste, waste to energy, effluent treatment system, dairy farm, manure management, modular digester, simple assembly, scalable, plug flow architecture, solids separator, digested manure, liquid fraction, solid fraction, nitrogen, phosphorus, greenhouse activities,, RFA, Scientific Discipline, Sustainable Industry/Business, Sustainable Environment, Technology for Sustainable Environment, Environmental Engineering, waste to fuel conversion, animal waste, agriculture, alternative energy source, dairy farms

Progress and Final Reports:

  • Final Report