Preventive Maintenance of Diffusers in Wastewater Treatment and Aeration Tanks
To ensure long-term high efficiency of aeration systems, it is essential to implement a preventive maintenance program for diffusers, aimed at reducing the risk of fouling and scaling while maintaining consistent oxygen transfer performance.
If the diffusers do not achieve the expected optimal flow rate over an extended period, a simple preventive cleaning procedure can be carried out by air scouring, using an air flow rate of approximately 2 times the maximum operating flow (up to 3 times for Newair diffusers).
In the presence of high levels of calcium bicarbonate, or organic or inorganic substances that may lead to fouling or surface scaling, a chemical cleaning of the operating system can be performed.
Selection of the acid solution
The choice of acid depends on the type of suspected fouling:
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Organic deposits
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Inorganic deposits
Generally, weak acids are used, such as:
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Formic acid 85%
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Acetic acid 80%
Acetic acid 80% is particularly suitable for inorganic scaling, such as calcium or magnesium salts.
Chemical cleaning procedure
To ensure effective removal of deposits, the following best operational practices are recommended:
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The acid injection point should be selected in an area where the air coming from the blower still has a temperature of approximately 70°C, a condition that improves dissolution and distribution of the reagent.
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The recommended dosage is:
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30–50 mg/m² of aeration surface (diffusion area), or
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5–15 mg/ml for tubular diffusers
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Intervention frequency
Under standard operating conditions, preventive cleaning is generally sufficient once per month, or whenever a significant increase in pressure (>100 mbar) is observed.
For further technical information or support in optimizing maintenance procedures, our technical team remains at your complete disposal.
