“Environmentally Superior” nutrient management systems could be determined by year's end.

Five nutrient management systems are now in the running for the highly anticipated Environmentally Superior Technology (EST) status, according to Mike Williams, director of the Animal and Poultry Waste Management Center (APWMC) at North Carolina State University (NCSU).

On July 21, Williams hosted a public forum on the NCSU campus where he highlighted the status of the 23 nutrient management technologies that have been evaluated by the APWMC since 2000.

The evaluations were conducted through a 2000 agreement between the North Carolina Attorney General's office, Smithfield Foods and Premium Standard Farms, and a 2002 agreement with Frontline Farmers, an organization comprised of independent pork producers and contractor growers.

Smithfield Foods agreed to provide $15 million for a landmark initiative to identify and develop environmentally superior nutrient management technologies, while the attorney general allocated $2.3 million from the $2.5 million Premium Standard Farms agreement, for a total of $17.3 million for this specific effort.

Frontline Farmers is not providing funding, however the organization's membership is cooperating with the state's attorney general and NCSU by providing farms for monitoring.

According to the agreements, technologies must be technically, operationally and economically feasible and eliminate the discharge of animal waste to surface or groundwater in order to be designated environmentally superior. These technologies must also substantially eliminate the release of ammonia, odor and disease-transmitting vectors and airborne pathogens and eliminate contamination of soil or groundwater with nutrients or heavy metals.

Three New Contenders

Williams didn't announce new finalists at the forum, but on July 25, he released a “Phase 2 Technology Determination Report,” in which he cited the only three new swine waste management technologies that met a rigorous 15-step technical performance evaluation process, and are thus considered as contingent EST:

  • The Super Soils Compost System utilizes a centralized processing facility with a mechanical mixing machine called a Compost-A-Matic. Manure solids are composted via aerobic composting in a series of enclosed windrows. Prior to composting, the solids are mixed with cotton gin residue and/or wood chips. The end products are Class A biosolids for use in soils.

  • The BGP Gasification System involves burning a substance in a low-oxygen environment at greater than 1,000° F., which converts complex organic compounds in the substance to gases. It is then possible to collect the resulting gases, such as methane, carbon monoxide and hydrogen, and make ethanol.

  • Fluidized bed combustion heats manure solids to greater than 1,300° F.

For both the gasifier system and the fluidized bed combustion system, end products are energy and ash. In the fluidized bed system, the swine solids are mixed with turkey litter prior to combustion. The remaining ash product is pathogen-free and has a high phosphorus content, suitable for fertilizer.

Following the technical performance evaluation of about half of these systems, two were designated as contingent EST in the “Phase 1 Technology Determination Report.”

These included the Super Soils liquid waste treatment system, which involves solids separation and phosphorus precipitation followed by nitrification and denitrification and an “ORBIT” High Solids Anaerobic Digester system. The latter is an enclosed anaerobic digester that processes a liquid and solid waste mix at a high temperature for the generation of biogas, which is converted into electricity.

All five systems may be considered EST pending the completion of economic evaluations by a 23-member economic advisory panel.

Economic Evaluations Coming

“We hope to have the economic evaluations completed by September,” Williams reports. “Environmentally Superior will only be designated for technologies that are deemed both technically and economically feasible by the advisory teams.”

The final evaluations of the five finalists should be completed by the end of this year, Williams projects.

“I recognize that the overarching answers hinge on the economic evaluations,” Williams says. “We have some tough issues to analyze yet, but I am cautiously optimistic that one or more of these five technologies will attain Environmentally Superior status.”

When the Environmentally Superior nutrient management systems will be implemented on a statewide or national basis, and whether legislation will be passed to require installation of Environmentally Superior systems are difficult to predict, Williams says.

“But once the final evaluations are in, we'll be at a stage where we can start to implement a timetable for industry-wide implementation of environmentally superior technology,” he adds.

View the Phase 2 Technology Determination Report, or Mike Williams' 40-page summary at: www.cals.ncsu.edu/waste_mgt/.