THE PROCESS
The State of North Carolina has led the effort to identify viable technologies that can effectively (and economically) eliminate the need for lagoons from hog farms and reduce the potential environmental hazard they represent. Many attempts have been made to find a viable way to remediate animal waste – in particular hog waste. Hog manure is very high in nitrogen and phosphorus, making it a real threat to the environment.

To date, the most widely used method of reducing this threat has been to contain the waste in a large pond, or lagoon, where the majority of the solid material settles and compacts on the bottom leaving relatively clean water at the surface. This water can then be reused to flush the hog houses or spray on surrounding fields – a common and EPA-approved practice. Spraying this water on fields theoretically dilutes the amount of nitrogen and phosphorus runoff, using them instead as nutrients for crops.

The use of an approved device called a separator can capture some waste solids before they enter the lagoon and these solids can also be applied to surrounding fields as fertilizer. The process for application of these liquid and solid wastes is well established and regulated. Still, there is growing concern that these methods are not adequately protecting the environment. For example, a significant rain event might result in a real danger of lagoon water and solids overflowing into surrounding estuaries and causing severe environmental damage – which is exactly what happened during hurricane Floyd.

NatureWorks Organics employs a combination of natural and commercial methods to capture and neutralize the hog waste solids, the primary source of environmental hazard. A separator is placed inline of the waste stream from the hog houses to initially capture the solid material when it is flushed out. The effluent from that process diverts to a settling process that captures the smaller, suspended solids. Most of those remaining solids are removed during a second pass through the separator, thus sending much cleaner water on to the lagoon.

All of the captured solid waste falls into a modified manure spreader and can then be fed to the earthworms in a controlled fashion. The worms are contained in an enclosed building, much like the hog houses. Their environment is built and maintained to maximize their consumption of waste, facilitate their feeding, and simplify the castings harvest. They are able to consume 100% of the solid waste fed them and produce castings in a ratio of about 1:4.
The entire process requires very little effort, energy consumption, and maintenance … especially when
compared to other remediation systems and methods
of producing fertilizer.

The nutrient-rich castings are harvested about every 9 months. Properly cared for, the worms are epigeic (they eat their way toward the surface) and reside in the upper 4-6 inches of the rows in which they live. NatureWorks Organics has in development a tractor-driven harvester that can remove the worms, harvest the castings, and return the worms to their home without damage or interruption of the remediation process.

No special permitting is required to remove the castings from the farm, unlike raw manure. The environmentally-safe, non-threatening nature of the castings is well established.

Once properly dried, the castings are processed to eliminate foreign objects (sticks, rocks, etc.) and then simply put in retail packaging for temporary storage or shipment to bulk customers. Any pathogens remaining from the harvesting are quickly consumed by the micro-organisms in the castings; this is verified by laboratory testing post-harvest on every batch. Testing by Ohio State University of soil/planting media applications also has shown that the positive micro-organisms in the castings actually eat bacteria and other organisms that are harmful to plants!