Filaments and Bacteria...
Volume - 9...

Appendix - 3...

Some Optimum Operating Conditions at a Treatment Plant...

pH...

- The influent pH should be in the range pH 6.0 – 8.5.
- Too low : Add NaOH or Ca(OH)₂.
- Too high : Add HCl ( Never H₂SO₄ ), sometimes Phosphoric acid depending on P.

Temperature...

The aeration tank temperature should be in the range 8 ^oC – 35 ^oC. Too high : Introduce cooler water if possible.

Nutrient Levels...

Influent nutrient levels should ideally be C : N : P = 100 : 5 : 1. Introduce N and/or P if there is a deficiency.

Dissolved Oxygen...

D.O. should between 0.5 –3.5 mg/l. Too low : Increase aeration. Too high : Reduce oxygen supply or reduce MLSS by wasting sludge.

Hydrophobic Substrates...

Hydrophobic substrates such as oils and fats promote filamentous growth. Improve pre-treatment e.g. use a D.A.F/ system or divert temporarily it feed streams are multi-sourced.