Generalized temperature dependence model for anammox process kinetics.

Area of Science:

• Environmental microbiology
• Wastewater treatment
• Biochemical engineering

Background:

• Temperature significantly impacts anammox process kinetics, with activity decreasing below 15°C.
• Existing models like Arrhenius and Ratkowsky equations show limitations in predicting anammox behavior at low temperatures.
• Understanding temperature dependence is crucial for optimizing anammox-based systems in diverse operational settings.

Purpose of the Study:

• To investigate the temperature dependence of anammox process kinetics from 10°C to 55°C.
• To evaluate the performance of existing kinetic models in this temperature range.
• To develop a new generalized temperature equation (GTE) for improved prediction accuracy, especially for 'cold anammox'.

Main Methods:

• Analysis of anammox process kinetics across a temperature range of 10-55°C.
• Comparison of commonly used models (Arrhenius, Ratkowsky) with experimental data.
• Development and validation of a new Generalized Temperature Equation (GTE) by dividing the temperature range into three segments.

Main Results:

• Ratkowsky equations showed good correlation (R²=0.93-0.96) for 10-55°C but failed at low temperatures (R²=0.36-0.48).
• The proposed GTE demonstrated strong predictive power across the entire temperature range (R²=0.97).
• GTE achieved excellent accuracy for the 'cold anammox' range of 10-15°C (R²=0.99).

Conclusions:

• The Generalized Temperature Equation (GTE) provides a more accurate prediction of anammox kinetics compared to existing models, particularly at low temperatures.
• GTE enhances the understanding and prediction of anammox process performance in both cold (mainstream) and thermophilic (sidestream) reactor conditions.
• This improved modeling capability supports the optimization of anammox-based bioaugmentation systems for diverse wastewater treatment applications.