The research project took place at the Georgia Institute of Technology in Atlanta, Georgia, and was conducted by John Pierson.

The new filtration method, called dynamic filtration, was tested on actual processing effluent and found to provide significant advantages over currently used filtration methods.

The initial treatment of processing facility effluents begins with primary screening to remove gross solids such as feathers, offal and other similar materials. Often secondary screens are employed to further remove finer solids comprised of fats and proteins.

These steps serve to not only recover materials for rendering, but also reduce the costs for operating subsequent chemical dissolved air flotation (DAF).

In practice low volume nozzle spray washes are used to continuously clean rotary screen surfaces. However, entrained particulate properties (size, density and miscibility) typically clog screen openings and diminish the volume passed through the screens over time.

Dynamic filtration gives increased recovery of fine suspended solids such as fats and proteins, providing more material for rendering.

The system differs from other filtration systems in that an innovative process uses backflow of clean or processed waters for continuous or near real-time surface cleaning, depending on operational mode.

In addition, it provides enhanced opportunities for water reuse and recycling inside a processing plant. The cost savings for the processing industry are estimated to be very significant. Longer-term savings would include reduced chemical costs.

Results indicate that scaling the system to full-size is not an issue although care must be taken to adequately size piping.

The project is part of the Association’s comprehensive research program encompassing all phases of poultry and egg production and processing. Publication of research papers resulting from the project is pending.