Inline analyser

The in situ measurement of ammonium and nitrate is now possible with the ISEmax CAS40. The robust inline probe is claimed to be able to reduce the energy costs associated with aeration systems in nitrification and denitrification processes in wastewater treatment.

The system features a transmitter and an ion-selective electrode installed in an immersion assembly. The probe is placed directly in the wastewater process and rapidly and continuously measures the concentration of ammonium and nitrate.

Ammonium is a highly toxic material that could prove harmful to downstream ecosystems if it is released without treatment. Purification is accomplished through a process of nitrification and de-nitrification. In a large aeration basin the concentration of ammonium is converted firstly to nitrites by means of aeration and then to nitrates by means of oxygen starvation. Measurements from the unit are used to control power and operation of the powerful aeration blowers. This ensures optimum energy use and proper activation of the sludge.

The unit is easy to use and set up and its rapid trend display supports the early control and regulation of the processes. The measuring system does not use any chemicals, is low maintenance and does not require external sampling. An integrated automatic compressed-air cleaning system prevents the membranes from fouling.

In municipal wastewater treatment plants, the ISEmax CAS40 measures the concentration of ammonium and nitrate directly during sludge activation and measures the ammonium load in the inlet to sludge activation. The measuring range is: ammonium-nitrogen (NH4-N): 0.1 to 1000 mg/L and nitrate-nitrogen (NO3-N): 0.1 to 1000 mg/L.

The system is a low-maintenance inline solution to optimising wastewater treatment plants, reducing labour and energy costs.