story to find out more.
In Duplin County,
N.C., a full-scale wastewater treatment system (foreground) that replaced the
swine lagoon. Click the image for more information about it.
Patrick Hunt (left), Matias Vanotti (center) and Ariel Szogi examine a sample
of calcium phosphate produced by the wastewater treatment system. Click the
image for more information about it.
New System Allows Efficient, Earth-Friendly Use of
Hog Waste By Luis
Pons March 7, 2005
A new method invented by Agricultural Research Service (ARS) scientists and collaborators for
treating swine-production wastewater may benefit hog producers and the
The researchers--soil scientists
Hunt at ARS'
Plains Soil, Water and Plant Research Center in Florence, S.C.--were
impressed with the system's stellar performance during a recent year-long
evaluation. According to Hunt, the system converted the evaluation site's brown
wastewater lagoon into blue, clean and aerated water. A patent is pending on
Relying on a mix of technologies developed by ARS and companies in the
United States, Spain and Japan, the system comprises tanks and staging areas
laid out over 200 feet. In three stages, it separates solids from liquids,
removes ammonia, recovers soluble phosphorus and processes the solids into
The researchers tested the system's ability to eliminate animal-waste
discharge--and related release of ammonia, odors and pathogens--to surface and
groundwater. They also gauged its ability to stem soil and groundwater
contamination by nutrients and heavy metals.
During the evaluation, the system removed more than 97 percent of
total suspended solids from wastewater. It also stripped the water of 95
percent of total phosphorus, 99 percent of its ammonia and more than 97 percent
of its odor-causing components.
The evaluation was conducted by the inventors and the private firm
Super Soil Systems USA of Clinton, N.C., on a full-scale version of the system
built at Goshen Ridge Farm in Mount Olive, N.C.
The testing system was constructed as part of an agreement between
Smithfield Foods of
Smithfield, Va., Premium Standard
Farms of Kansas City, Mo., and the
North Carolina Attorney
General's office to use environmentally superior technology to replace
current waste lagoons.
more about this research in the March 2005 issue of Agricultural Research
ARS is the U.S. Department of
Agriculture's chief scientific research agency.