Fig. 2
From: Spatial monitoring of hydrolysis in a plug-flow bioreactor: a support for flexible operation?
Development of gradients of the pH-value, conductivity and ORP between the inlet (blue), center (red) and outlet (black) ports in PFR1 (left column) and PFR2 (right column) under dynamic conditions. A substrate change is indicated by a dashed line, changes in HRT or thin-sludge recirculation (R) are marked in grey/white and phases of bioaugmentation are marked in yellow. Changes of the microbial community and the acidogenic metabolism are indicated by the variations in the distribution of the produced SCCA