Development of an Integrated Livestock Wastewater Treatment System

The goal of this research is to develop an energy-efficient system that will abate the water pollution and odor problems associated with concentrated animal feeding operations and yield, as added benefits, a commercial fertilizer and a recyclable water stream. Waste management is a major concern of every large-scale livestock operation and a growing problem nationally as animal feeding operations are increasingly concentrated. It is not that animal wastes are without value; in fact, nearly 40 percent of feed dry matter and 75 to 85 percent of the nutrients fed to animals is excreted as waste. The challenge is to convert what is currently viewed largely as a problematic waste into useful end products. The wastewater treatment system proposed here integrate three treatment processes to eliminate wastewater "lagoons" and their attendant problems. The processes are: 1) separation of the liquid effluent from the residual solids remaining after anaerobic digestion: 2) single- or - two stage aeration; and 3) appropriate membrane separation.