Letter 242

Removing boron from wastewater

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I am interested in removing boron and boron compounds from a wastewater stream.

If anyone has any ideas I would appreciate hearing it, or if they can point me in the right direction it will also help.

Thanks.

Dan W. [last name purged for privacy due to age of posting]

Sorry, I don't know how to do it. Our environmental directory, however, includes a few people you might want to talk to.

Ted Mooney, P.E.  finishing.com Brick, New Jersey

We are currently researching boron treatment. There appears to be some limited evidence that boron reduction (10 to 30% depending on the concentration - >10 mg/L and process) can be achieved in some conventional treatment plants. No reduction data for boric acid. Research is for a landfill with 10 to 15 mg/L boron levels. Treatment objective is less than 5 mg/L. At levels greater than 50% reduction, literature suggests a micro-filtration process.

John Stidwill
- Ottawa, Ontario, Canada

I am also looking for wastewater treatment technologies for the removal of boron.. any current literature? any help greatly appreciated.

James P [last name purged for privacy due to age of posting]
- Hot springs, AR

We have also been on a 4 month long search for cost effective boron removal from wastewater.

The raw wastewater contains varying amounts from 100-1100 mg/l of B (as borate we believe). Conventional treatment technologies (metal hydroxide precipitation) has brought the levels down consistently to 100 mg/l from 1100 and to 30 mg/l from 100.

Our goal is to reach levels below 4 mg/l consistently. The only technology which appears to work (thus far) is Ion Exchange. This technology is extremely expensive, and we have been researching other options.

The most recent attempt (reverse osmosis) has brought our levels down to 13 mg/l.

If you or anyone else has some ideas or success, please let me know.

Thank You.

Mark E. Morgano, P.E.
- Plainville, CT

If you're interested in high removal rates of Boron, the way to go is EDI (Electro deionization). Another option is to use two step R.O. which will leave you with 25 % remaining in the feed (75 % removal). Good luck and greetings from the Netherlands

Jorg Korver
- the Netherlands

We are removing boron from wastewater, using an RO system operating with preconditioned effluent, it is on service since January with consistent results below 10 ppm

RogÈrio Toledo de Almeida
- Guarulhos, Sao Paulo, Brazil

We are currently removing Boron from 200 ppm to 6 ppm by using crossflow microfiltration after chemical pretreatment.

Israel Garden
- Haifa Israel

I do research on removal boron from wastewater. I'm using RO and then use the sample after RO treatment, do the adsorption with activated carbon. The result so great...less than 1 ppm boron.

Suriyati Saleh
University Technology Malaysia - Johor, Malaysia

You might want to try filtration using zeolite medium. Or use bentonite clay chemicals. Results are very good.

Redzuan Razak
- Shah Alam, Selangor, Malaysia

Boron compounds are reduced under high pH. Depending on the process and objectives, pH precipitation is likely indicated and advisable. There are some ion exchange compounds that can achieve the desired level, again subject to objectives.

For example: a zeolite process with caustic soda may raise the pH to 9.5 or 10. This may precipitate elemental boron by 60%. Complex boron or bound boron complexes may require a higher pH, and caustic soda may not be a suitable agent. If reductions at 98% level are required, suggest another agent to raise ph to 11, then design neutralization complex to suit (i.e. sulfuric acid or carbonization...subject to cost efficiency process selection).

John Stidwill
- Ottawa, Ontario, Canada

I would like to ask from others regarding the treatment of high boron influent from leachate wastewater. The leachate wastewater originated from the hazardous waste landfill. I've done few test on chemical precipitation with zinc sulphate and ferrous sulphate. Both chemicals give 50-65% removal of boron. The influent boron concentration is around 150-200 ppm. Is there any other experience in removing boron from wastewater using chemical precipitation. ( RO systems are very expensive and not feasible ).
Another question that I have is my treated wastewater especially from the leachate wastewater turns black after storing in the tank for few days ( without any movement ). I believe that the black color is due to the FeS that presence in the water. I tried to aerate the water and add some sodium hypochlorite to accelerate the sulfide oxidation to sulphate. However, it seems that it takes along time to oxidize the FeS. ( adding the hypochlorite oxidizes the sulfide and produced Fe(OH)3 sludge ). My question is is there any way that I can solve the issue and should I aerate and add some oxidizing agent in the equalization tanks prior the treatment with ferric chloride?
Highly appreciated if anyone can contribute some ideas.

Muhamed Jaffar
Sr. Process Engineer - Leachate Treatment Plant - Malaysia

What may be the chemical reaction for removing BORON from existing water sample.

What shall be the Chemical / ingredients to be used.

J.K.Mukherjee
- Kolkata, India

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Ed. note: Readers who wish to answer, please do so. Readers who are looking for answers please see our FAQ on waste water treatments for boron. It lists the more than 20 threads on this topic that are on line here.

Chemical precipitation is the best way to remove boron. Usually precipitates out at ph above 9+ followed by acid adjustment.

John Stidwill
Ottawa, Ontario, Canada

We have used peat for boron removal, in the first stage we compared four knid of adsorbents Basalt, peat,compost and activated carbon and we found peat is the best. the result of this part of our study will be publidhes in journal of environmental technology "INVESTIGATION OF ORGANIC, INORGANIC AND SYNTHETIC ADSORBENTS FOR THE PRE TREATMENT OF LANDFILL LEACHATE". Then we compared three kind of peat to find which one has the best performance and finally we did field studies. The result of this part of the work will be submitted to publish very soon, too. Also we compared the effect of environmental factors on adsorption of boron from landfill leachate. The result has published "Adsorption of boron from landfill leachate by peat and the effect of environmental factors".

Haleh Shahriari
Uottawa.ca - Ottawa. Ontario, Canada