-> Continuation about WWTP part 10 ♻️💧Lanjutan tentang WWTP part 10 ♻️💧Mohamad Khoirul HudaHead of Industrial Services at Nestlé ...
Published on by Hossein Ataei Far, Deputy Manager of the Research, Technology Development, and Industry Relations Center at NWWEC
Lanjutan tentang WWTP part 10 ♻️💧
Mohamad Khoirul Huda
Head of Industrial Services at Nestlé
Issue problem and follow up action WWTP appears an unpleasant odor in the aeration tank, even though when checking the SV30 on the normal aeration tank is standard, the clarifier is also normal there is no sludge bulking but there is a smell in the aeration process, some of the steps that can be taken below are not 100% able to solve the problem, depending on the severity of the condition of the WWTP / WWTP system, The following is an explanation of the causes and steps that can be tried to be taken;
1. SV30 condition is safe + no bulking
a. This indicates flocculation and sedimentation are running normally
b. Microorganisms can still form a good floc
2. Smelly aeration (usually rotten egg smell/H₂S or other septic smell),
This is usually caused by;
a. Lack of oxygen (DO too low)
b. Aeration is not enough → the process becomes anaerobic or anoxic, producing odors
c. Organic load overload (high loading rate)
d. BOD too high goes into aeration → microbes can't decompose all the smell →
e. Sludge too old / MLSS too high
f. Microbial cells are already dormant (endogenous respiration) → decompose → odor
g. Dead zone in aeration tank
h. There are parts that are not aerated → local anaerobic
Actions that can be tried to be taken;
1. Check DO (Dissolved Oxygen)
- Ideally > 2 mg/L in the aeration tank
- If it is low, → increase aeration (blower, maintenance diffuser, etc.)
2. Check the MLSS and sludge age
- Ideal MLSS 2,000 – 4,000 mg/L depending on the design of the WWTP
- If it is too high, → do sludge wasting by running a screw press / belt press / decanter, etc
3. Monitor BOD/COD Inflow
- Check if there is a spike in organic load (for example due to dumping/product leakage from the production process), if so, it may be necessary to check that the equalization tank is optimized by dilution and adjust the feeding to aeration
- Pre-treatment before aeration is optimized
4. Check mixing and flow in the aeration tank
- Are there stagnant zones?
- Do a visual check (scum, dark foam, local smell)
- Clean the diffuser, make sure the blower is pressurized
5. Observe the floc condition in the Microscope (if there is access)
- Do filaments start to appear? (early warning sludge bulking)
- Are protozoa dominating? Can help analyze biological conditions
Example of a simple action (action);
a. DO < 1.5 mg/L -> Add aeration/check blower & diffuser
b. MLSS > 4,000 mg/L -> Reduce the life of the sludge, do sludge wasting
c. High BOD load -> Optimize tank EQ, control of waste feeding to aeration
Note: the values of the DO and MLSS parameters above are in general, for the exact value can be adjusted to the design / type of WWTP used.
Thus a little sharing from me, if there is something that is not appropriate or needs to be completed, I am happy to be open to input from all friends, thank you.
Hope it is useful 🙏
Link: https://www.linkedin.com/posts/mohamadkhoirulhuda_lanjutan-tentang-wwtp-part-10-issue-activity-7355504989907177473-Rlkh?utm_source=share&utm_medium=member_desktop&rcm=ACoAAEBDhzIBsyuiuDI0-eiNhRpHh9ad-Axkqtk