▷ Question 1: What is the better carbon to nitrogen ratio for denitrification in practice? Is it below 5 or 6-8?
A: In practical application, I personally think it is better to control the carbon to nitrogen ratio at 6-8.
▷ Question 2: Salinity of 2% produces some inhibition of nitrifying bacteria, does it mean pure sodium chloride?
A: Pure sodium chloride is used in the laboratory; in actual application, there may be a little change, but basically controlled at about 2%, more than 2% of the bacterial activity will be affected more.
▷ Question 3: Is the bacteria you introduced suitable for ordinary activated sludge method or can it be combined with contact oxidation and carrier fluidized bed?
A: All of them can be used. Basically, as long as it is a biochemical system, it is theoretically possible to apply special strains of bacteria for biological enhancement.
▷ Question 4: What is the general dosage of nitrifying bacteria for urban wastewater treatment plants?
A: The dosage is generally referred to two data, one is the concentration of ammonia nitrogen in the influent water, urban sewage treatment plant is generally in the 30-50mg / L, the effluent control in the 5mg / L or less; the second is the residence time, urban sewage treatment plant is generally not much nitrifying bacteria, the dosage of roughly one in 100,000, it is recommended to use the three times in the early stage, which will ensure the effect of a better.
▷ Question 5: What is N-serve in the nitrifying bacteria inhibitor?
A: It is a very complex compound 2-chloro-6-(trichloromethyl)pyridine.
▷ Question 6: Which is more effective, sodium carbonate or sodium hydroxide, for the alkalinity that needs to be replenished during nitrification denitrification, and what is the difference?
A: It will be more effective to use sodium carbonate, but it will be more expensive.
▷ Question 7: How well do nitrifying bacteria tolerate toxic shock? What is the load of denitrifying bacteria?
A: Nitrifying bacteria are usually not very good at tolerating toxic shock, because they are autotrophic bacteria, and they are greatly affected by more toxicity. It is hard to say the load of denitrifying bacteria alone, it depends on the amount of bacteria in the pool.
▷ Question 8: In our AO operation, the pH of aerobic tank is 6.2, COD 600mg/L, ammonia 140 mg/L, how much pH adjustment is appropriate? Is it OK to add soda ash in aerobic tank?
Answer: pH adjustment of 7.0-7.5 is usually sufficient, and it is OK to add flake soda.
▷Q9: Is your product solid? Does it need to be activated?
A: Nitrifying bacteria are liquid, denitrifying bacteria are solid.
▷ Question 10: Seeing that there are many cases of special wastewater with limited water volume, I would like to ask about the cost of strain preparation and how long does it take for specific microorganisms to be applied to engineered problem solving from preparation to effect?
A: Generally speaking, strains of bacteria can be prepared on a large scale very quickly. The cost of preparation varies according to the strain, bacillus strains will have lower cost, nitrifying bacteria is chemoautotrophic type, the cost will be relatively high; in addition, if special storage is needed, the cost will be high.
Usually strains are introduced in and the effect can be seen in a week or so.
▷ Question 11: Is there a natural attenuation process after the specific bio-bacteria are put in and there is no shock to the incoming water? In the case of petrochemical wastewater treatment that you cited, the effluent first declined significantly, and then there was a gradual fluctuation and increase over time.
A: This is related to the bacterial strain. Some bacteria can exist in this environment for a long time with little or no attenuation, such as nitrifying bacteria. Other bacteria will decay over longer periods of time, at which point they need to be supplemented in. This is related to the characteristics of the strains themselves, as their introduction into an activated sludge system will compete with indigenous microorganisms.
▷ Question 12: Is there any data on the rate of nitrification, the rate of denitrification, that is, how many grams of ammonia nitrogen or nitrate are degraded by a single gram of bacteria per hour?
A: The best nitrification rate can be 800mgNH4+-N/(L-h), denitrification rate is more difficult to measure, and accurate data is not yet available.
▷ Question 13: I see that there are a lot of literature that says that nitrifying bacteria also have requirements on the starting concentration, what do you think?
A: The higher the ammonia concentration, the more the nitrifying bacteria are inhibited, even though they have the function of removing ammonia.
▷Question 14: Can your mature products be adapted to various wastewater qualities and how long does it take to adapt to different water qualities?
A: The bacterial agent will have a short adaptation period for different water qualities. In general, the nitrifying bacteria will be able to work in three days, but it will be guaranteed that it will definitely work in seven days.
▷Question 15: Have you measured the effect of surfactants on nitrifying bacteria, and what other inhibitors of nitrifying bacteria are there?
A: Surfactants have not been measured, and there are many kinds of inhibitors, so you can check for yourself.
▷Q16: Besides acetylene, what are some common toxic substances that affect nitrifying bacteria and nitrosochemical bacteria?
A: Some common antibiotics against gram-negative bacteria, heavy metals (Cu and others) are also more sensitive.
▷ Question 17: How long do denitrifying bacteria stay in the anoxic zone for best results?
A: The amount of nitrate and the concentration of bacteria will affect the residence time, generally more nitrate, the residence time should be longer.
▷ Question 18: How long is the generation cycle of nitrifying bacteria and denitrifying bacteria?
A: Nitrifying bacteria is a chemoautotrophic bacterium, the reproduction is slower, the generation cycle is longer, usually the reproduction of a generation is 10h or even dozens of hours, which is also a reason for the high cost. Denitrifying bacteria is a large class, including many kinds of bacteria, can convert nitrate into nitrogen are, generation cycle will be shorter, breeding faster, now common on the market, the generation cycle is basically in dozens of minutes.
▷ Question 19: The reflux goes directly back to the anaerobic tank, can the denitrifying bacteria act fully?
A: Return flow to anaerobic certainly not, because denitrification should be carried out in an anoxic environment.
▷Question 20: How high is the starting concentration of ammonia to inhibit nitrification?
A: Different strains of bacteria react differently to the starting concentration of ammonia. Normally, ammonia concentration over 100mg/L will inhibit nitrifying bacteria.
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| Diethylene Triamine Penta (Methylene Phosphonic Acid) (DTPMPA) | CAS No. 15827-60-8 |
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| HexaMethyleneDiamineTetra (MethylenePhosphonic Acid) HMDTMPA | CAS No. 23605-74-5 |
| Polyamino Polyether Methylene Phosphonic Acid(PAPEMP) | |
| Bis(HexaMethylene Triamine Penta (Methylene Phosphonic Acid)) BHMTPMP | CAS No. 34690-00-1 |
| Hydroxyethylamino-Di(Methylene Phosphonic Acid) (HEMPA) | CAS No. 5995-42-6 |
| Salts of Phosphonates | |
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| Penta sodium salt of Amino Trimethylene Phosphonic Acid (ATMP•Na5) | CAS No. 2235-43-0 |
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| Potassium salt of 1-Hydroxy Ethylidene-1,1-Diphosphonic Acid (HEDP•K2) | CAS No. 21089-06-5 |
| Ethylene Diamine Tetra (Methylene Phosphonic Acid) Pentasodium Salt (EDTMP•Na5) | CAS No. 7651-99-2 |
| Hepta sodium salt of Diethylene Triamine Penta (Methylene Phosphonic Acid) (DTPMP•Na7) | CAS No. 68155-78-2 |
| Sodium salt of Diethylene Triamine Penta (Methylene Phosphonic Acid) (DTPMP•Na2) | CAS No. 22042-96-2 |
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| Partially neutralized sodium salt of bis hexamethylene triamine penta (methylene phosphonic acid) BHMTPH•PN(Na2) | CAS No. 35657-77-3 |
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| Polyacrylic Acid Sodium Salt (PAAS) 45% 90% | CAS No. 9003-04-7 |
| Hydrolyzed Polymaleic Anhydride (HPMA) | CAS No. 26099-09-2 |
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| GLUTARALDEHYDE | CAS No. 111-30-8 |
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| Tolyltriazole (TTA) | CAS No. 29385-43-1 |
| Sodium salt of 1,2,3-Benzotriazole (BTA•Na) | CAS No. 15217-42-2 |
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| Oxygen Scavenger | |
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| Other | |
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