Control of bacterial foaming in activated sludge process by chlorination

Abstract

Nocardia amarae ST6, isolated from a local sewage treatment plant, was suggested to cause foaming in activated sludge process. Toxicity tests by using pure cultures showed that N. amarae ST6, the foaming bacterium, was more sensitive to hypochlorite than other non‐foaming bacteria such as Pseudomonas aureginosa ST1 and Escherichia coli ST2. Results of toxicity tests in a laboratory‐scale activated sludge unit confirmed the success of using chlorination to control Nocardia foaming in activated sludge process.

Key words:

• Foaming
• Activated Sludge
• Chlorination