Removing Phosphorus from Liquid Manure


The paper discusses evaluated components of sequential manure filtration systems, including liquid-solid separation, chemical treatment, and supplemental stages.

The study took place in central Pennsylvania, part of the Chesapeake Bay Watershed.

A variety of approaches have been proposed to treat animal manures to reduce their potential for adverse environmental impact.

The Liquid-Solid Technologies they evaluated were:

  1. Auger Press
  2. Fiber Filter
  3. Decanter Centrifuge
  4. Membrane Filter
  5. Auto-Vac®
  6. Ancillary Components
  7. Assembly of Manure Treatment System Components

The Alar Auto-Vac® Model AV220 was tested.  After testing the other technologies, the Auto-Vac® was chosen for the final liquid-solid separation step. The solids removed by the Auto-Vac® comprise of 10% of the total solids and 40% of the ARP. These solids can serve as a concentrated source of phosphorus  (P) and manure solids and can be sold to operations where land application of P is not limited or can be used on the farm, but be economically transported to greater distances away from the milking barn than can liquid manure.

Read the full article at



Church, C. D., A. N. Hristov, R. B. Bryant, P. J. A. Kleinman, and S. K. Fishel. 2016. A novel treatment system to remove phosphorus from liquid manure. Applied Engineering in Agriculture, 32: 103 – 112. DOI 10.13031/aea.32.10999