If it's not filamentous, then either Surfactants, Nutrient imbalance, fines from an anarobic digester, or Toxicity. What is the appearance of the foam? Is it white or brown, stiff or billowy or slimy? Surfactant foams are usually lighter color and billowy. It's good to keep a couple of different defoamers on hand to try, to see what's effective for this. Nutrient imbalance is something to look at as well. Do you calculate the C:N:P ratio on your Influent? If the foam is slimy and you do an india ink test under the microscope you should be able to tell if polysaccharides are building up in the floc, which is an indicator for this. Another possible cause of foam is toxicity, but your microscope photo looks OK. Just to check though - are you seeing Ammonia levels rise, or cloudiness in your Clarifiers/DAF ?
Published by Leah Miller, Wastewater Treatment Plant Supervisor / Environmental Coordinator at Foremost Farms USA
If it's not filamentous, then either Surfactants, Nutrient imbalance, fines from an anarobic digester, or Toxicity.
What is the appearance of the foam? Is it white or brown, stiff or billowy or slimy? Surfactant foams are usually lighter color and billowy. It's good to keep a couple of different defoamers on hand to try, to see what's effective for this.
Nutrient imbalance is something to look at as well. Do you calculate the C:N:P ratio on your Influent? If the foam is slimy and you do an india ink test under the microscope you should be able to tell if polysaccharides are building up in the floc, which is an indicator for this.
Another possible cause of foam is toxicity, but your microscope photo looks OK. Just to check though - are you seeing Ammonia levels rise, or cloudiness in your Clarifiers/DAF ?