MLSS-MLVSS
B.M. D’Antoni, F. Iracà, M. Romero
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1. Analytical method for the determination of MLSS and MLVSS
Procedure to be followed using the instruments already present in your laboratory.
2. Determination of MLSS
- Set the temperature of the muffle at 105°C;
- Weight the blank filter and take note (Mo) [mg];
- Filter 25 ml of sample and take note of the volume (V) used [ml];
- Take the filter (after filtration) and put it in the muffle at 105°C for 2h;
- Let the dried filter for 15 min at room temperature;
- Weight the filter after dehydratation and take note (M1) [mg];
- Calculate the MLSS by the following formula.
3. Determination of MLVSS
- Set the temperature of the muffle at 550°C;
- Put the filter after dehydratation (M1) into the crucible;
- Weight the crucible+filter and take note (M2) [mg];
- Put (M2) into the muffle at 550°C for 1h;
- After 1h take out the crucible and let it cooling for 30 min at room temperature;
- Weight the crucible after incineration and take note (M3) [mg];
- Calculate the MLVSS by the following formula.
4. How to take note
| Samples | MLSS (105°C - 2h) | |||
|---|---|---|---|---|
| Weight blank filter (MO) | Sample Volume (V) | Weight filter after dehydratation (M1) | MLSS concentration Equation 1 | |
| Oxidation tank | ||||
| Return sludge | ||||
| Samples | MLVSS (550°C - 1h) | ||
|---|---|---|---|
| Weight crucible+filter (M2) | Weight crucible after incineration (M3) | MLVSS concentration Equation 2 | |
| Oxidation tank | |||
| Return sludge | |||
If your balance weight value is in grams, multiply the results x 1000 in order to obtain mg.