Analyzers, in-situ sensorsand samplers

Liquid analysis – Water & Wastewater

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Outlet After biological treatment, the wastewater settles in the secondary clarifier. The sludge settles on the floor and can be reused as activated sludge or surplus sludge. The clear water is drawn off and directed as clean water into public bodies of water via the drainage canal. What is measured? In clear water: • Ammonium and nitrate measurements are indicators of the ability of the wastewater treatment plant to reduce the nitrogen load > CA80AM, CAS51D • SAC, COD and TOC measurements document the degradation efficiency of the wastewater treatment plant with regard to the carbon load >CAS51D, CA80COD, CA72TOC • The measurement of phosphate in the form of PO 4 3- • Sampling in combination with comprehensive quality monitoring proves compliance with legal discharge limits Continuous monitoring of the discharge values ensures safety. Complete documentation can be used as proof of wastewater treatment performance to the authorities, and also for internal monitoring purposes. As the sludge profile is monitored, changes caused by a heavy downpour, for instance, can be detected quickly and countermeasures can be taken. or P tot provides information on the rate of phosphate removal > CA80PH, CA80TP

Nitrification During the nitrification stage, oxygen is used to reduce the remaining ammonium to nitrate. Some of the wastewater is returned to the denitrification stage for further nitrate reduction and to „inoculate“ the fresh wastewater. What is measured? • The ammonium measurement indicates how much ammonium has been reduced > CAS40D, CA80AM with CAT820 • Oxygen is measured to help regulate and control the efficiency of the reduction process. Too little oxygen slows down the process while too much drives up operating costs > COS61D • Orthophosphate measurement is used to regulate and control the dosing of precipitants > CA80PH with CAT820 Aeration accounts for up to 70% of the power used in biological wastewater treatment plants. Sensors for ammonium, nitrate and oxygen can reduce aeration and thus lower the energy consumption of the plant.

Ammonium, phosphate

Ammonium, nitrate, phosphate or total phosphorus, SAC, COD or TOC, samplers

Nitrification

Secondary clarification

Outlet