During wastewater treatment, aeration is part of the second processing step after solid waste has been removed. There are several methods of aerating the water, but a typical aeration tank diagram is shown below:

Schematic-diagram-of-a-typical-activated-sludge-process
Source: www.researchgate.net/figure/Schematic-diagram-of-a-typical-activated-sludge-process_fig1_290037644

Wastewater aeration has several purposes. First, it removes dissolved gases from the water, such as CO2 and H2S. It also oxidizes dissolved metals to remove them from the solution.

Wastewater also naturally contains microbes that feed on organic matter. These microbes are aerobic, so they need oxygen to break down the waste. Aeration exposes them to oxygen, allowing them to grow and form “flocks” that can then easily settle out of solution. A portion of the settled sludge is returned to the tank to promote further microbial growth.

Flow control is needed to ensure that the microbes get the oxygen they need while also ensuring that the tank is not over-aerated. Over-aeration wastes energy and resources and breaks the flocks apart. This keeps the microbes suspended in the solution, and they cannot settle out.

This wastewater treatment facility uses Alicat MFCs to deliver air into their treatment tank at specific setpoints.

APPLICATION NOTES
Fast track eligible! Mass flow controller for use with 5 SLPM of air for pilot work in an aeration of wastewater application. Inlet pressure of 100 PSIG outlet pressure of atmospheric. 4-20 mA analog signal along with power supply.

REPRESENTATIVE PART NUMBERS FOR THIS APPLICATION
— MC-5SLPM-D-PCV30 / CM, CIN, GAS: Air, P1: 100 PSIG, P2: ATM
— PVPS24U

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