Published by Ahmed Khafagy, Technical support Team
We have a river water plant which treats the river water to drinking water, using the ultrafiltration (UF) system.
The intake water has high ammonia content.
What is the best way to remove the ammonia or reduce it to drinking water levels?
There is no wastewater system in our city (southeast asia) so our raw water is effectively untreated wastewater with ammonia often at 7 or 8mg/L, sometimes up to 10mg/L. We have installed MBBRs (moving bed biological reactors) as the first stage of our WTPs and get very good ammonia removal (up to 85%). The MBBRs are also relatively cheap and easy to install and operate. In addition, as we run conventional WTPs up to 350ML/d, we have stopped pre-chlorination and get additional biological treatment in the filter beds... though obviously need 100% assurance on your post-chlorination.
Published by Evan Hambleton, Director at Palyja
If you want to solve the problem in the stream itsel, stratigaly placing large rocks to creat turbalances and lowering the depth of the water in some places may be the best option, and let nature do the rest. but this also depends on to stream flow and the concentration of the amonia.
Published by Oz Ihia, Engineering manager at P2W
Chlorination works but chloramines need to be removed. Oxidation-reduction reaction causes ammonia removal problem.
If present ionically,cation resins work well if low in hardness for water.
Natural zeolites with salt regeneration works well.
Aeration being the key for oxidation removal of Ammonia,I suggest ozone microbubbles for drink water.
WQA TECHNICAL APPLICATIONS BULLETIN
is a useful ref..also Water Technology magazine website
Published by Suresh Kumar.S
Ammonia can be present in water in two forms, either ammonium hydroxide (NH3) or as the ammonium ion (NH4).
When the pH of the water is less than 7 the ammonia is present as the ammonium ion. As pH increases above 7, more of the ammonia is present as ammonium hydroxide.
The ammonium ion is readily removed by cation resin. Good removal capacity can be expected in waters low in hardness. Waters that are high in hardness will have decreased capacity due to the simultaneous affinity and removal of calcium, magnesium and the ammonium ion.
Published by Rahul Kumar, Product Development Manager at Whirlpool Corporation
You are right on target. Bhaskar Maillmadugula. Environmental multitasking. May I suggest these points. poor water, sick plants and fish, locked up nutrients, decrease of O2, anaerobic conditions. Multitasking solution = adding RNA microbial group called Archaea to the river (managers decide where to begin), The Archaea will breakdown all organic compounds into their elemental/nutritional state, chelate any and all toxic metals, increase O2 content, fish and plants become healthy and multiply, Ammonia in water is consumed, no need for river water to be treated. Eliminates the need for any chlorination. Pathogen testing daily will remain at ZERO. People drinking this super oxygenated water will be much healthier. ( thanks for the diatoms tip, microbiology professor said he ate mud pies as a child just to get his daily supply of diatoms). Take care!
Published by Guy McGowen, President/CEO/Chief Science Officer
Thanks. We grow Diatoms by dosing micro-nutrients, not by adding Diatoms to the water. All natural waterways would have Diatoms, when micro-nutrients are added, these diatoms grow rapidly. The downside of drinking filtered water is that Diatoms too are filtered out, along with bacteria.
Published by Bhaskar Mallimadugula, Kadambari Consultants Pvt Ltd - Director
What does "adding RNA microbial group called Archaea" mean? I'm a microbiologist and it makes no sense to me! As far as we know, no Archaea conduct oxygenic photosynthetic, so how can they "increase O2 content"?
Published by Mike Dempsey, Managing Director, Advanced Bioprocess Development Ltd.
I suggest that the fixed bed adsorption filtration process be applied at this water treatment plant. This process is very efficient. Good adsorbents for the ammonium ion can be used as: vermiculite, activated carbon etc. I hope I've helped you.
Published by Carlos Henrique Catunda Pinto, Professor and Researcher at UERN - Brazil
The chlorine may be a good disinfectant for removing the ammonia in river water. The chlorine may be added by supplying bleaching powder at the intake point of the river water.
Published by Md.Mezanur Rahaman, Assistant Municipal Engineer at AQUA Consultants and Associates
the best way maybe to treat the water with sulphuric acid to form ammonium sulphate & use it for irrigation, the ammonium sulphate in the water will be a fertilizer after experimenting if it is useful to grow crops for 6 months.
Published by balbir singh, researcher on water for agricultural irrigation
Ammonia is a fertiliser already! Why you add sulpharic acid?
Published by Liang Qiao, Chief Process Specialist at ZJ High New Pty Ltd
I think It's about when you scrub ammonia out you usally have to use sulpahric acid. you'll get ammonium sulphate in the end.
Published by Doy Schellekens, Advisor wastewater technology / Innovator
You did not note the starting ammonia concentration. Assumming it is low parts per million concentration, then, in addition to the many great suggestions below, breakpoint chlorination. That will have the additional benefit of disinfection of the drinking water source.
Published by Ken Martins, Global Practice Director, Industrial Water
Raise the ph to 8, aerate and nh4 will voilitilize
cheap and simple
Published by Jud Hill
Raise the ph to 8, aerate and nh4 will voilitilize
cheap and simple
Published by Jud Hill
There are following method to remove ammonia
1.Air stripping at elevateted pH(9.5-10.5)
2. Biological Treatment
3. Adsorption by Zeolite(Ion Exchange)
4. Use chemical like H2SO4 and then neutralise.
5. Distillation with steam
The general approach to ammonia removal would be primary and polishing softeners. Ammonia is removed preferentially to sodium by cation resin, but is displaced by calcium and magnesium. Therefore, a single softener will remove ammonia during the initial part of its cycle but will then release the ammonia as it becomes exhausted with hardness.
Softening can be used effectively for ammonia removal if the primary softener is allowed to load to a hardness endpoint and a polishing softener is used to remove ammonia. In this case, the primary softener must not be operated to hardness breakthrough, as this would cause an ammonia spike and lead to elevated ammonia levels in the final product water.
Published by Prem Baboo, Researcher at www.researchGate.net
Air stripping is not a good idea, unless the ammonia gas is captured. Otherwise, you simply put the ammonia back into the terrestrial and aquatic environments via precipitation.
Published by Mike Dempsey, Managing Director, Advanced Bioprocess Development Ltd.
Aeration is the key to removing ammonia.
Published by Steve Byg, CWP, Certified Water Professional - Water Quality Chemist at Ixom Watercare
High ammonia levels signify anoxic/anaerobic conditions.
If you want to eliminate the source, check of the river contains nitrificating organisms and look at ways to aerate the river water.
Lowest cost would be the planting of aquatic plants known to oxygenate the water, though this would take some time to take effect.
Alternatively you can have a aerated biological stage (activated sludge or MBR) prior to your UF. Fast, but higher operating costs over time.
Published by Alain Ducheyne, DHI Water & Environment Singapore - Project manager
Planting of aquatic plants will only oxygenate the water during the day. At night, the plants will consume oxygen and could cause severe oxygen depletion, leading to further problems such as fish kill.
Published by Mike Dempsey, Managing Director, Advanced Bioprocess Development Ltd.
Thanks
I'm interested to know more about aquatic plants and how it works
Published by Ahmed Khafagy, Technical support Team
Grow Diatoms. They will consume the ammonia and produce oxygen. Diatoms are the natural food for fish, so the fish in the river will increase.
So our solution is to use the ammonia to grow fish , just as farmers use urea to grow crops.
Published by Bhaskar Mallimadugula, Kadambari Consultants Pvt Ltd - Director
Growing diatoms will only oxygenate the water during the day. At night, they will consume oxygen and could cause severe oxygen depletion, leading to further problems such as fish kill.
Published by Mike Dempsey, Managing Director, Advanced Bioprocess Development Ltd.
You are right on target. Environmental multitasking. May I suggest these points. poor water, sick plants and fish, locked up nutrients, decrease of O2, anaerobic conditions. Multitasking solution = adding RNA microbial group called Archaea to the river (managers decide where to begin), The Archaea will breakdown all organic compounds into their elemental/nutritional state, chelate any and all toxic metals, increase O2 content, fish and plants become healthy and multiply, Ammonia in water is consumed, no need for river water to be treated. Eliminates the need for any chlorination. Pathogen testing daily will remain at ZERO. People drinking this super oxygenated water will be much healthier. ( thanks for the diatoms tip, microbiology professor said he ate mud pies as a child just to get his daily supply of diatoms). Take care!
Published by Guy McGowen, President/CEO/Chief Science Officer
Can apply screening to trap the dead fish/ animals far away upstream and also try aeration to reduce BOD for left behind organics that may be increasing ammonia in the river
system.
Published by LOKESH PUNJ, A B.TECH. Agr Engg, PGDM-SPA IIMA (1977-9) 25 yrs in Water Piping / Irrigation/Infra Projects
The best method of treatment is to eliminate the source.
Ammonia can indicate some other even more harmful risks, and so the source should be at least investigated and eliminated if possible.
Tom Keenan
Published by Tom Keenan
There are three ways to remove ammonia 1.) raise the pH to 10.5 and air strip it (can be expensive to adjust pH up then back down) 2.) use a zeolite like Clinoptilolite and absorb the ammonia then use the zeolite as fertilizer (this can be expensive in high flows). 3.) use biological removal using an aerated/anoxic process to convert ammonia - nitrite-nitrate. This assumes that increased nitrate levels are not a problem.
Published by Derek French, Wateropolis Inc. - Founder
Dear mr Khafagy,
I'm sorry to repeat one of the answers below, but eliminating the source of high ammonia in the river might be the first and maybe cost-effective approach.
However, you may have already considered this and may not be an option. (sorry another repeat)
You could go for a classical take on the matter, using either a activated sludge system , fixed bed system or indeed go full chemical and use Ozone.
Stripping is an option.. but it’s effectiveness is somewhat dependent on the initial concentration (what’s high in your case?) A route you could consider is the use of ion exchange (either thru natural zeolites or resins) Regeneration of the zeolite will require a brine solution, and you’ll eventually end up with a highly ammonia concentrated brine solution. What you could consider to do with this is stripping and scrubbing, obtaining a ammonium sulfide solution, which has value on its own.
Somewhat more advanced ( or should I say, not a 100% technologically ready yet) is to use the solution to obtain single cell protein.
Good luck on finding a solution,
Best regards
Doy
Published by Doy Schellekens, Advisor wastewater technology / Innovator
Colleagues are right:Amonia should be removed Before reaching à river. It often results from over fertilising in Agriculture which is a major source bringing ammonia to rivers.
in Germany an industrial technology called stripping is now applied to wastewater. The investment is not higher than other technologies and brings a plus: armonía can be recycled.
But in order to find the optimal solution, please consider the source of contamination, the concentration on ammonia in the water, opportunities an selling cost of recycled ammonia and the flow to be treated
with kind regards
thomas