Hi everyone,
I extracted a bioflocculant from a Klebsiella sps. (isolated from activated sludge). That flocculant showed good flocculation in kaolin suspension with the aid of both CaCl2 and FeCl3. But it was not able to perform flocculation in any real waste waters. There was no flocculation while the flocculant added to the waste water with and without CaCl2. When the flocculant added with FeCl3 it induces the flocculation. But the parameters were not improved than the sample treated with the FeCl3 alone. What would be the reason and how can I improve the flocculant?
Hi Kaarmukhilnilavan
If possible, use polymers
Polymers are effective flocculants because they are strong molecules with the ability to carry charges. Small particles can become trapped in the curves of the polymer due to their size, accumulating enough mass to limit their retention in the solution.
Dear Rs Kaarmukhilnilavan,
did a bioflocculant work in your case for kaolinite without the presence of Ca(2+) and Fe(3+)? Here, https://www.nature.com/articles/srep34980 the bioflocculant from Klebsiella flocculated kaolinite at the presence of iron. Flocculation was iron-dependent.
But the major question is another: I suppose that wastewater differs from kaolinite suspension. Why did you consider that if the flocculant is effective for kaolinite suspension, then it will work also for wastewater? Wastewater typically contains multiple organics, and not necessarily suspended clay particles. A bioflocculant components adsorb to clay particles but they may not interact with hydrophilic and smaller-size organic components of wastewater such that the bioflocculant does not work. In contrast, multivalent metals will flocculate both clays and dissolved or suspended organics, by complexing and bridging molecules and particles in larger aggregates. So, perhaps, your bioflocculant is not effective towards organics in wastewater?
these articles may be useful:
Article Characterization and flocculation mechanism of a biofloccula...
Article Optimization and characterization of polysaccharide-based bi...
Article Exploration of Performance Kinetics and Mechanism of Action ...
Article Characterization and application of bioflocculant prepared b...
Article Fermentation and kinetics characteristics of a bioflocculant...
pH adjustment of either wastewater or acidic/alkaline treatment is an essential step. 2nd reason is low molecular weight and ionicity/charge of the bioflocculent particles. 3rd is selection of suitable bioflocculent. Another is, pollution characterstics (especially trace metal composition) of the wastewater.
Vijay Sodhi Sir, is there any methodology to measure the ionicity of the biopolymer like bioflocculants?
Hi, it brings a project of over 20 years ago. We needed to treat very turbid groundwater with high concentration of cyanides. For the removal we needed clear water with low turbidity, low concentration of suspended solids.
FeCl3 dosing gave a lot of small flocs, blocking filtration.
We ha a lot of activated sludge available... Justy traces did help to flocculate, and a lamela separator was sufficient for clarification
- Badges
- Science topic
- Similar topics
- Geoscience
- Asia
- India