Separation/Nitrification-Denitrification/Soluble Phosphorus Removal/Solids
The two elements of this project, a liquid treatment system and a solids processing facility, are located at two different sites. The liquid treatment system is located at Goshen Ridge Farms, a 4,360-head finishing farm near Warsaw, North Carolina. Owned by Lewis Fetterman, Jr., Goshen Ridge Farms is under contract for production with Premium Standard Farms. The solid waste management portion of this project is located at Timber Ridge Farms near Clinton, North Carolina. C. Ray Campbell, vice president of research and development for Super Soil Systems USA, leads the technology team for this project.
Liquid treatment begins with separation of the solid and liquid portions of the waste stream. Solids separation is accomplished using polyacryalmide, a flocculating agent. The solids are transported to the Clinton site, where they are composted and blended with other materials using a proprietary process to produce a growth media. This value-added product is then bagged for sale and use off the farm. A portion of the solids is being used in evaluating another technology, the Orbit High Solids Anaerobic Digester.
The liquid portion of the waste stream flows between tanks in a circulating loop undergoing denitrification as a result of aerobic activity in one tank and nitrification through the use of concentrated nitrifying bacteria in the second tank. Nitrogen is removed from the waste stream during this stage of the process. The liquid then flows to a settling tank, where phosphorus is removed through the addition of calcium hydroxide and a dewatering bag system. Calcium phosphate, which has value as a fertilizer, percipitates out during this process, providing a second value-added product. The pH of the liquid is raised during phosphorus removal, which kills bacteria and viruses. Roughly 80 percent of the liquid is recycled through the hog houses, while 20 percent is used to irrigate crop fields.
Technology Provider: Super Soil Systems USA, Inc.
M. Fetterman President and CEO, Super Soil Systems USA, Inc.
Ray Campbell, Ph.D. Vice President for Research & Development and Project
Technology Evaluation Team
Matias B. Vanotti
Patrick G. Hunt
Frank J. Humenik