We are working to find a solution for Nitrate removal, from an effluent contaminated with Nitrates (1,600 ppm). Nitrate is found as a salt of K+ in the effluent.
The effluent water volumes range from 600-800 m3/d. The expectation is to bring the NO3- to 30 ppm. appreciate expertise.
You could use the RO after remove the COD and the system solids.
In most of the cases the most economical path to remove the COD is biological. Maybe in this case the COD could be remove (if it is not recalcitrant) using the biological way.
I think some of the steps that could be explored are:
COD removal (Biologic1: Anaerobic or MBBR Aerobic) >> COD removal (Biologic2; MBBR) >> AOP (Ozonation, if it is necessary) >> MF >> Membrane filtration >> Evaporation of the obtained concentrate
I recommend you a pilot test of the suggested system you decide use or explore.
With our technical partners we can help you with some of this steps.
If you have enought area and climate you could evaporate all the water or just the concentrate.
If the nitrate were the only concern, it could be discharged to sewer directly. In the sewer, it will denitrified and converted into nitrogen gas. The benefit would be additional oxygen to control the anaerobic condition of the sewer. It is common practice to add nitrate salt into the sewer system.
Hello Thanks, however we don't have a sewer system ( a central system to negotiate this water volume ) where the operation is carried out. But thank you for the insight.
Nitrate is present as Potassium Nitrate. You are draining out 1552.6 to 2073.6 kg of Potassium Nitrate per day in the effluent. KNO3 is used as fertilizer. Please send the detail analysis to develop the recovery process for KNO3.
Thank you, for the suggestion please check the flowing , which may be useful
the source of water is due to a buffering process carried out to cation exchange Ca++ with K+ in a natural grow Medea (Coconut Peath ) .
Ca++ is introduced as Ca(NO3)2 . Pls check the results of the analysis.
In addition to K+ there is Ca++ and Na+ in considerable amounts.
However pls check bellow the current analytical report. We will be doing a fresh assessment of the effluent again with mote details on the Cations present. will let you Have that as well, soon.
Water volume 800-1,000m3/d
Conductivity:4800MicS/cm
COD:1150
BOD:125
pH5.5-6.5
Chlorides659
Other parameters (Minerals, etc):
Nitrate as No3 : 1100 - 1750 mg/l Nitrite as No2 : 30 - 60 mg/l
Our objective: To remove NO3- to 30ppm or closer.
May you sent more analytical data and the source of this waste water that will help all everyone can sharing on the right way. KNO3 is salt you can use RO
with costly so before this waste is produced you can find out many way to solve with low price. aggasit2012@gmail.com. BKK Thailand
Thank you, for the suggestion please check the flowing , which may be useful
the source of water is due to a buffering process carried out to cation exchange Ca++ with K+ in a natural grow Medea (Coconut Peath ) .
Ca++ is introduced as Ca(NO3)2 . Pls check the results of the analysis. We have carried our trial to substitute the Ca(NO3)2. We used CaCl2 & Ca(OH)2 , but the cation exchange rate was not satisfactory.
In addition to K+ there is Ca++ and Na+ in considerable amounts in the effluent .
However pls check bellow the current analytical report. We will be doing a fresh assessment of the effluent again with mote details on the Cations present. will let you Have that as well, soon.
Water volume 800-1,000m3/d
Conductivity:4800MicS/cm
COD:1150
BOD:125
pH5.5-6.5
Chlorides659
Other parameters (Minerals, etc):
Nitrate as No3 : 1100 - 1750 mg/l Nitrite as No2 : 30 - 60 mg/l
Our objective: To remove NO3- to 30ppm or closer.
May you send more analytical data for the effluent and it's origin; especially the COD : N ratio and its origin? We can help you design a conceptual layout using German software packages for free. Contact us at rsaed@birzeit.edu
Thank you, please check the flowing , which may be useful
the source of water is due to a buffering process carried out to cation exchange Ca++ with K+ in a natural grow Medea (Coconut Peath ) .
Ca++ is introduced as Ca(NO3)2 . Pls check the results of the analysis.
Water volume 800-1,000m3/d
Conductivity:4800MicS/cm
COD:1150
BOD:125
pH5.5-6.5
Chlorides659
Other parameters (Minerals, etc):
Nitrate as No3 : 1100 - 1750 mg/l Nitrite as No2 : 30 - 60 mg/l
Our objective: To remove NO3- to 30ppm or closer.
Thanks Mark for the suggestion, we have looked at the Annamox biological denitrification, but the available "C" content was a hindrance. However we will go through your link to learn more.
Considering that potassium K+ is the counterion of the nitrate NO3- to be removed, I would recommend to consider to recover KNO3 which is a valuable fertilizer and raw material in various production processes.
In this way, your wastewater produces revenue instead of consuming a lot of money to reduce nitrate to nitrogen gas and to remove the corresponding potassium as in the conventional wastewater treatment approach.
Thanks for the suggestion, we are in search for a technology for a cost effective Evaporation , to concentrate this water, since the water volume is quite high. 800-1000m3/d.
As you suggested we plan to check the potential of making a concentrated liquid fertilizer.
Thanks. Evaporating such a high volume of water requires a huge amount of energy and is not really sustainable even when using solar energy. Instead I would recommend to first concentrate the KNO3 using NF/RO membranes as to recover clean water for reuse and then evaporate the RO concentrate with the KNO3.