The anaerobic process needs to be combined with an aerobic process to reduce sludge volumes. I suggest either retrofitting an aeration tank into the existing treatment plant or a membrane bio-reactor. Using membranes will provide better separation efficiencies than a settling tank, especially in colder temperatures.
Depending on the design and membrane selection, a membrane bio-reactor should provide final treated effluent with BOD
Pre-screening before biological treatment to around 100-microns for removal of non-soluble BOD/COD, followed by secondary micro-screening for residual removal of non-soluble BOD/COD. More information available at www.baleen.com
prem is correct. very perceptive. you can have a dual aerobic anaerobic reactor. and you can also have them in tandem. anaerobic and the followed by combined for polishing.
We can help you further treat your effleunt after anaerobic digestion to meet discharge norms / recycle the treated water to achieve ZLD.
We have distillery spent wash treatment based on Electro-Chemistry and we can treat this effluent without any chemicals to colourless odourless water as per CPCB standards.
Your effluent match distillery spent wash to a greater extent other than high temperature at the time of generation. We have recently tested some samples of bio-methanated bakers yeast effluent from SAF YEAST Chinckpokli unit.
If I were you, I will select several UASB in series. As a food process waste water, the BOD can be easily reduced to a very low level as indicated by Mr. Gerd Teunissen, via COD < 200 mg/L. UASB or other anaerobic process is very efficient and suitable to treat this concentrated highly biodegradable wastewater.
Look into a BVF anaerobic reactor system from ADI Systems. If aerobic polishing is required, the BVF can often take the wasted sludge from the aerobic system and digest it further. It is a low cost, low sludge production system, with multiple installations on molasses applications.
You can improve existing system by Enhanced treatment by polishing off the residual biodegradable oxygen demand from effluents of anaerobic reactors, or the biodegradation of recalcitrant wastewater pollutants, usually requires sequenced anaerobic and aerobic bacteria activities. However, the combined activity of both bacteria can also be obtained in a single reactor. with either pure or mixed cultures showed that anaerobes can tolerate oxygen to a certain extent. The oxygen toxicity to methanogens in anaerobic sludges quantified in batch experiments, as well as in anaerobic reactors. The results showed that methanogens have a high tolerance to oxygen. In practice, it was confirmed that dissolved oxygen does not constitute any detrimental effect on reactor treatment performance. This means that the coexistence of anaerobic and aerobic bacteria in one single reactor is feasible and increases the potentials of wastewater treatment.
It is a good idea to go for a second anaerobic digester. Do you have experience on this ( please Share if possible) any article , research paper is also welcome.
I was operating such a system in Arrow Ecology, Israel. Arrowbio-global.com
I can check your vertical velocity and OLR as well as suggest a secondary reactor or different operational scheme, according to water analysis and operational parameters
Its sounds gud that u are working on ZLD.but first i remind u, ZLD plants having their limitations bcz its very costly based on loads so better we try to minimised BOD/COD load but as you mention their final outlet Range is high bcz now UASB performance is below level,it might be increased upto 90%.
and for your sludge concer i suggest you plz go through centrifuge/decanter using poly electrolytes dose for better sludge dewatering.if any query plz feel free any time.
DEAR SIR, we are in Brazil, in our country there is many industry of alcohol combustible , we use process by electrolysis, with Ti4O7 (composite) plates and rectifier with high effcience, if yoy want more details I can send for you. this water can be used like recycled water in same Industry by 3 process electrolysis... conductivity after was half and others characteristics you can see in picture...
References some of my experiences, from UASB reactor we through to Up flow Fixed bioremedetion media, and arrange the recycle sludge from 20-40% to anaerob equil pond. The afforded bod/cod degradation will in the 75-85% it's depend on the pH level control and no any poison or retarded microorganisms growth. Some times reach to 90% removal of BOD/COD.
UASB reactor removal of BOD & COD is reasonably good, as remarked, but should be improved to up to 80%. Sludge can be reduced by drying in drying beds after dewatering to 20% DM. Since this is a food industry, total digestibility should be good enough to reach final COD < 150 mg/l with aerobic treatment, but pH correction and N & P dosing are absolutely necessary.
You can do a small scale study using multi-chamber anaerobic digester on untreated effluent itself and generate biogas and then on discharge from anaerobic digester ,use aerobic treatment/usab to get irrigation water. In Pilot test, observe the rate of digestion at different Ph levels and also result of mixing a small quantity of cattle dung slurry. Oils/ grease is an inhibiting and thus undesirable factor.