A candidate technology
of the North Carolina Agreements Project:
Development of Environmentally Superior Technologies
per Agreements Between the Attorney General of North Carolina
and Smithfield Foods, Premium Standard Farms and Frontline Farmers
(Innovative Sustainable Systems
Utilizing Economical Solutions)
project has become known by the acronym ISSUES, which stands for Innovative
Sustainable Systems Utilizing Economical Solutions. It involves three
different technologies located on three different farms, while a fourth
technology, the microturbine generator, is being evaluated as an element
of one of the three ISSUES technologies. The three farms on which ISSUES
technologies are being evaluated are all owned by Murphy-Brown and are
all in Duplin County.
Disgester (foreground) and Filtration System (rear)
RENEW (Recycling of Nutrient, Energy and Water) System
Located at Vestal Farms, the RENEW System employs a mesophilic digester
as well as aeration and a wastewater filtering and disinfection systems.
This project also incorporates the microturbine generator. Waste flows
from pig barns first to equalization and concentrator tanks, which serve
to produce a thickened liquid. This liquid then flows to a mesophilic
digester. The digester, which operates at a temperature of 95 degrees
F, produces biogas, which is used to fuel the microturbine generator.
The generator produces electricity, which is sold and used on the electric
power grid. The waste stream then flows to a polishing storage basin,
then to an aerobic digester, also called a nitrification pond. A portion
of the waste stream then flows back to the polishing storage basin,
where it is used to flush the pig barns and is sprayed on crop land
if necessary. The remaining portion of the waste stream flows through
a filtration system. The filtration system consists of sand carbon filters
and reverse osmosis. The water is then disinfected using ozonation and
ultraviolet light. Filtered and disinfected water is returned to the
pig barns, where it is used as drinking water for the pigs.
Permeable Lagoon Cover
This project is located on Harrells Farm. The permeable cover being
tested is the Bio-Cap ML, which is patented. Waste flows first to a
lagoon fitted with a permeable cover. The cover is designed to reduce
ammonia emissions and odor. The lagoon is anaerobic. Waste then flows
to a nitrification pond, which is aerated, then to a denitrification/irrigaton
storage pond. The liquid in the denitrification pond is returned to
the pig houses and used to flush waste to the covered lagoon and sprayed
on cropland as necessary.
This project is located at Carroll's Foods Farm #2529 near Turkey. Waste
flows first to what is described as a covered anaerobic pond; however,
the cover is a layer of aerated water sprayed over the top of the pond.
This aerated layer is designed to reduce ammonia emissions and odor.
Wastewater then flows to an aerated nitrification pond and finally to
a denitfication/irrigation storage pond. Liquid from the last pond is
returned to the pig houses and used to flush manure and sprayed on cropland
The RENEW system and part of the Aerobic Blanket system were provided
by Smithfield Foods, led by Prince Dugba. The Permeable Cover technology
was provided by BEI, Inc., led by John Baumgartner in close cooperation
with Prince Dugba. The microturbine generator system was designed by
Bob Hoffland, P.E. of Hoffland Environmental Inc.
Dr. Leonard Bull
Associate Director, Animal and Poultry Waste Management Center
North Carolina State University
Phone: 919.515.6836 E-mail: email@example.com
here for a printer-friendly
PDF version of this information
here to return to the projects list