What is an aeration basin?
The technique of injecting air into wastewater to facilitate aerobic biodegradation of organic compounds is known as aeration. Aeration basins (sometimes called aeration lagoons) are holding or treatment ponds that use artificial aeration to promote wastewater biochemical oxidation.
What are the Causes of Foam on Aeration Basins?
This is the light foam that is commonly observed on aeration basins. Biological by-products such as proteins, polysaccharides, and biosurfactants, which are crucial components of microbial activity, produce this foam.
When sprayed with water, this foam becomes white to light brown and immediately collapses. When starting up a new aeration tank, it's common to see more foam since rapidly dividing bacteria emits more cellular by products than more steady, decline phase growth.
What are the causes of Stiff White Foam?
The followi?ng are some possible causes of stiff white foam:
-Activated sludge is not returned to the aeration tank;
-Low MLSS due to process start-up;
-Low MLSS for present organic loading due to severe sludge waste or a large organic load from an industry;
-The presence of unfavourable circumstances in the activated sludge system, such as toxic conditions (pH below 6.5 or over 9.0), insufficient DO, nutritional inadequacies, or seasonal (winter/summer) temperatures, which are most noticeable on weekends;
- Inadvertent solids loss from the secondary clarifier.
What are the causes of Excessive Brown Foam?
These foams are often associated with plants that operate at low loading ranges. Plants that are designed to nitrify and are in the nitrification mode produce low to moderate volumes of dark brown foam.
The following are some of the most likely reasons of excessive Brown Foaming:
- The aeration tank is being run at a low F/M because the regulatory agency requires nitrification;
- Due to insufficient sludge waste, a high MLSS concentration develops. When wastewater temperatures shift between the winter and summer seasons, this situation might emerge unintentionally, affecting microbial growth and activity;
- Sludge re-aeration mode is active;
- Ineffective waste management programme.
Control of Foam on Aeration Basins
How to control a Stiff White Foam?
When trying to solve a foaming problem, try the following measures:
- Check if the aeration tank is receiving return sludge. Maintain a sufficient return sludge rate to maintain a normal secondary clarifier blanket (1ft to 3 ft.);
- For a short time, stop squandering activated sludge to restore MLSS levels and MCRT to the desired range;
- Control air flow rates to keep DO between 1.0 and 3.0 mg/l. Fine bubble aeration may cause foaming to last longer than course bubble aeration;
- Consider bringing in seed activated sludge if necessary.
How to control Excessive Brown Foam?
When trying to s?olve a foaming problem, try the following measures:
-If nitrification is not necessary, gradually increase the F/M while decreasing the MCRT;
- Include the volatile solids extracted in the scum in the waste sludge calculations if the scum is not returned to the aeration tanks. The amount of volatile solids eliminated with the scum during typical operation is insignificant;
- During periods of high foam, however, 10 to 15% of the solids may be eliminated along with the scum. If filaments form, attempt to figure out what's causing them;
In maintaining a wastewater treatment facility, don't underestimate the value of simple observation. Colour, odour, and foam changes all indicate that something has changed. Netsol Water provides a complete variety of standard and fully configurable wastewater treatment systems, as well as their comprehensive maintenance. Choosing a trained, accredited, and experienced wastewater system specialist will considerably boost your chances of long-term satisfaction with your overall system.
We have over 10 years of experience custom-designing and manufacturing wastewater treatment plants. You can schedule a conversation with our engineer or obtain an estimate by visiting our website. We can guide you through the process of determining the best solution and a reasonable price for your wastewater treatment system requirements.To begin the conversation, please contact us at +919650608473 or send an email to enquiry@netsolwater.com for further information or product purchase related query.
