Are K-strategists yield-strategists in disguise? An example from autotrophic nitrogen removal.

The behavior of heterotrophic bacteria growing in systems with low or no external supply of chemical oxygen demand (COD) has become more relevant within the wastewater context. Growth strategies help to clarify how bacteria behave and adapt to different environmental conditions. In the case of substrate limited conditions, research has been mainly focused on the k-strategy, whereas another important strategy: the yield strategy has not been explored intensely.

A multi-component model for granular activated carbon filters combining biofilm and adsorption kinetics.

Along with the rise of biological active granular activated carbon (bGAC) filtration as advanced treatment technology for wastewater treatment plant (WWTP) effluents, the mathematical representation of such systems is gaining increasing importance. This work introduces a model that describes the performance of bGAC-filters for Dissolved Organic Carbon (DOC) removal from a WWTP effluent. The DOC removal within bGAC-filters is accomplished by two mechanisms: adsorptive removal and biological transformation.

Membrane Aerated Biofilm Reactors - How longitudinal gradients influence nitrogen removal - A conceptual study.

Membrane-aerated biofilm reactors are becoming more important for nitrogen removal in the wastewater sector. One-dimensional (1D) models are widely used to study the performance of such systems; however, 1D models are not able to simulate the longitudinal gradients that exist in the reactor. Although there is experimental evidence that points to the existence of longitudinal gradients simple modeling approaches that consider these gradients are not yet developed.