Pilot-scale investigation of phosphorus removal from swine manure by the manure phosphorus extraction (maphex) system

Swine manure is typically in slurry form and contains nitrogen (N), phosphorus (P), and organic material that is beneficial to crops. Unfortunately, for economic and logistical reasons, manure tends to be applied to soils near where it is produced and P concentrations increase to the point that they are often in excess of crop demands. With the implication that runoff of excess P contributes to eutrophication of streams and other water bodies, farmers are experiencing increasing pressures and regulation to not apply manure to those soils. We previously reported on an invention capable of removing P from dairy manures. This pilot-scale study shows that the MAPHEX System can remove greater than 96% of the phosphorus in swine manures, and strongly suggests that, once scaled up, the essentially P free effluent could be beneficially used for fertigation without further loading the receiving soils with P. This scaling up has the potential to reduce storage volumes to allow for mitigation of overflow problems during large storms. Furthermore, this study suggests that capital equipment costs and treatment costs for swine manure would be lower than for treating dairy manure.