Fluoride removal

[cdwarkan]

Hi, I work in a semiconductor company and am looking for treating fluoride in our wastestream.we have a flow of 450-550 gpm and the fluoride concn is around 50 ppm and we want to bring it down to < 5ppm.

I know the conservative technology of lime and Activated alumina, but how do you deal with the sludge.You need to dewater the sludge and dispose it off as hazardous or non hazardous waste depending on the other wastes in the water.

Is there any other means of treating fluoride without any hazzles of sludge.

Thanks
CD

 

[orenda1168]

Cdwarkan:

Any way you slice it, you will have a sludge disposal issue. Contact Dave Orlebeke at eoh2o.com or 541-557-4108 about the applicability of his electrolytic oxidation process to fluoride removal, which he has experience with.


Orenda

 

[cdwarkan]

Thanks for your reply. Will sure contact DAve.

Regards

 

[Muggle]

CD - We spoke last week on this fluoride issue - you were going to send me over the analysis - but I have not recieved. Either way - if you would like a sample photo of what the precipitate would look like and the level created - please email me at....aquaticonsult@yahoo.com....or start@eoh2o.com - which is the website email address.
Thanks -
Dave Orlebeke
Aquatic Technologies
(541) 557-4108

 

[bimr]

Not really any other methods since fluoride is extremely poisonous and it will obviously be in the sludge.

Of course, if you could find some way to purify the fluoride, you could sell it to the toothpaste manufacturers.

 

[cdwarkan]

Hello,

How about crystalized reactors for fluoride removal.No sludge, no dewatering its all crystals and its non hazardous and can be left open to sun for drying or have a vaccumm to suck up all the water. but again Disposal? Any ideas as to what can be done with the crystals DAve?

I will send you the analysis soon. Its been crazy around.I am sorry about that.

 

[Muggle]

Hi back....use for fluoride crystals. Boy, that's a new one. I suspect some glass companies might be able to use in various kiln processes - also various chemical manufacturers. However, not sure your going to be able to provide sufficient quantities for them. Glass/artistic pottery - maybe. There are some really different techniques out there - but otherwise, I have no clue
Dave

 

[orenda1168]

Cdwarkan:

Crystals?? If these are fluoride compounds, which I presume is the case, Bimr's comments about them being a poison is still true, which then puts them into a hazmat catagory.


Orenda

 

[bimr]

If memory serves me correctly, you are probably neutralizing waste HF with lime and ending up with calcium fluoride. The problem that you will run into is that the waste sludge has too many contaminants to make it worthwhile to recycle.

Have you contacted companies such as MEMC for help?

http://www.p2pays.org/ref/18/17146.pdf

 

[cdwarkan]

Hey,

You know what? I will investigate more on this crystal bed reactors for fluoride removal and get back to you guys in a couple of days.

Its a pretty cool concept but the disadvantage of this system is there should be a continuos flow of water to the crystals.If in case the pump fails, the crystals clog and becomes a mess.

Will keep you guys posted.

Regards