Hi, we have just started up a new plant in Arizona for industrial wastewater pretretment Our installers and engineer have been gone and out of state and haven't provided training yet so I am looking for some advice.
What sampling needs to be done and what frequency for the MBBR bioreactors. We have two towers about 75k gallon each capacity. This is followed by a DAF unit before discharge to treatment plant. We are in the works of getting COD/BOD testing from influent and effluent to calculate demand. However, our industrial wastewater is deficient in nutrients(carbon), nitrogen(ammonia), and phosphorous. Sugar will be main nutrient being provided for the MBBR. However, we still need to supplement. Is the 100:5:1 CNP ratio advisable for a MBBR tank with industrial wastewater?
These are the sampling I believe need to be done for the proper C:N:P ratio.
TOC
TN
TP.
On top of COD/BOD sampling.
Is SVI needed or even possible to grab in a MBBR or DAF? Do we need to inspect microorganisms, "bugs", growing on biofilm in MBBR towers?
Any advice on the frequency of these samples. Daily, weekly, or monthly?
I believe i will start a discussion on the DAF unit as well because I am not familiar with operator specs needed. I've looked at some parameters for psi and recycle water from treated DAF effluent.
Any help or teaching is greatly appreciated!
En general the sampling frequency depend on wastewater flow
What kind or method of pretreatment you expect to use?
Note that Carbone C is not considered as nutrient.
The current daily flow is 100,000 GPD. Which will slowly increase as production grows.
The only pretreatment before the MBBR and DAF is pH control mixing tanks, using caustic or sulfuric acid depending on pH of influebt.
Right now we are doing a BOD7 test and 7 day COD test to get our baseline.
We are doing TOC, TN, and TP test next week. We are deciding if we should test before the pH mixing tanks or after?
Should the total carbon, nitrogen, and phosphorous sampling be done on influent or MBBR towers.
Thank you for reply!
Just be more precise on the sampling frequency, this would depend on hydraulic residence time and on any expected water quality dynamics on the inflow.
For example, if you have a residence time of 1 day and you expect your water quality to vary only on a day to day basis, then it is likely that samples at higher frequencies than one day will not vary much. Thus it makes more sense to make only daily samples. This is of course a crude simplification but I guess you get the point.
The sampling frequency should be related to the expected variations in your influent, if this is pretty stable sampling once a week can be sufficient. My experience though says that at many industrial sites there are large variations and in this case dayli sampling must be recommended to be able to adjust Nutrient dosing. Sampling should be flow proportional composite sampling. You should consider PO4-P instead of Tot-P since this is what the biology needs also NH4-N, NO3-N and NO2-N can be useful in the effluent of the MBBR to evaluate how you biologi is working. Do not forget pH and Alkalinity.
SVI makes no sense in front of the DAF.
Thank you Kim for your input. I will switch to PO4-P. Do you recommend the the PO4-P and NH4-N daily as well? I believe these test take a couple days to complete so maybe wouldn't be as helpful as daily COD sampling.
Yes, I've learned a lot more about the DAF and the MBBR and SVI makes no sense for MBBR. Any test or sampling recommended for DAF unit?
Thank you!
For NH4-N and PO4-P in the effluent I would recommend 2 - 3 samples per week in the effluent is recommended since if either of these values will be below 0.15 mg/l you Biology will be suffering.
Would it be prudent to sample after MBBR system but before DAF unit? Wouldn't the DAF remove ammonia and phosphorous and skew what is actually coming out of MBBR tanks? Thanks again!
- Badges
- Science topic
- Similar topics
- Organizational Psychology
- Training