Simulation of Thermal Hydrolysis at the Blue Plains AWT: A New Toolkit Developed for Full-Plant Process Design

Abstract

Model simulations can support design and cost calculations for both anaerobic digestion and sidestream treatment in order to evaluate the implementation of innovative thermal hydrolysis technologies in the context of the entire plant. SBR based influent characterization, sludge production calibration, and bench-scale digestion experiments of TH-treated sludge from Blue Plains WWTP have been conducted. In the mesophilic pilot digesters of 15 and 20 days retention time COD-removal efficiencies of 56% and 60%, respectively, have been achieved compared to 50% in the control. The resulting data set has been used to calibrate the introduced model approach: The mathematical model for growth of acetoclastic methanogens considers free ammonia inhibition and limitations of undissociated acetic acid as substrate. The impacts of these two compounds appeared very relevant for high-solids digestion and the model provided better understanding of these process interactions.

Population balance models: a useful complementary modelling framework for future WWTP modelling

“…Additionally, the non-ionized form of acetic acid was designated as an inhibitory substrate using the Haldane equation as suggested by Fukuzaki et al (1990). Detailed descriptions on modeling of THD are provided in previous publications by Wett et al (2009 and.…”

The kinetics of process dependent ammonia inhibition of methanogenesis from acetic acid

“…Previous research shows that ammonia inhibition of aceticlastic methane generation is relatively mild at low unionized ammonia concentrations and follows a logistic reduction in methanogenesis as ammonia is increased, theoretically leading to full inhibition of methanogenesis at sufficiently high concentrations (Angelidaki and Ahring, 1994). As such, the following logistic model has been applied to calculated LI NH3 values (the L prefix referring to the logistic model applied measured I NH3 values) via least-squares regression (Wett et al, 2009):…”

Municipal Wastewater Treatment Plant Model with Sludge Pretreatment Incorporation for Design and Feasibility Determinations

“…More recently, a conventional heating (CH) CAMBI simulation using a developed BioWin TM toolkit for full-scale design was explored by Wett et al (2009). The constructed toolkit permits cost calculations for AD and CH to be performed in the context of a complete advanced wastewater treatment plant (AWTP).…”