with a total hydraulic volume of 869 L. The cells
were constructed with PVC sheets reinforced with angle iron
frames. Each cell was equipped with a gas flow meter, temperature
probe, and high-level alarm. Wastewater was diverted from the
plant influent through a two-step system. First, a grinder sump
pump located in the plant influent channel pumped wastewater to
a 910 L tank. The tank was mixed and operated to maintain a
maximum detention time of 15 min. Second, a Watson Marlow
peristaltic pump fed influent wastewater from the 910 L tank
through a 5 cm PVC downcomer pipe to the bottom of the first cell
of the ABR.