Mr. Kade has a Bachelor’s Degree in Civil Engineering, and a Master’s Degree in Environmental Engineering from Marquette University in Milwaukee WI. Master’s research was focused on enhanced anaerobic digestion using TPAD for the City of Janesville WI. Mr. Kade has almost 20 years of experience working for technology manufacturers in the wastewater treatment industry such as Siemens/Evoqua, Parkson, and Environmental Operating Solutions. Mr. Kade’s expertise includes Biological Nutrient Removal processes and Biosolids Management. Mr. Kade is a licensed professional engineer in the State of Wisconsin.

To avoid costly carbon addition, facilities with insufficient influent VFAs that need an effective biological phosphorus removal, can encourage additional VFA production through fermentation. An anaerobic selector provides the optimal environment for the uptake of VFAs by PAOs, but PAOs constitute a small subset of the bacterial population in the mixed liquor suspended solids (MLSS). The rest of the bacteria are switching gears to ferment organic compounds to obtain food and energy. These facultative bacteria do not consume VFAs; they break down complex soluble organic compounds to form VFAs, allowing the PAOs to take up additional VFAs and release phosphorus. Therefore, the anaerobic selector or fermentation tank in an EBPR facility simultaneously conditions PAOs and provides an environment for additional fermentation of soluble organics to VFAs.

The purpose of this presentation is to discuss how to optimize the anaerobic fermentation process by alternating a short mixing cycle with a long deep cycle. The system is designed to adapt to changing process conditions to maximize volatile fatty acid (VFA) formation and biological phosphorus removal. The deep cycle stratifies the reactor in order to increase anaerobic solids retention time (SRT), minimize oxidation-reduction potential (ORP), and maximize VFA formation.