Mercury removal from produced water 3

[techv]

Folks,

We need to meet mercury levels of 5 ppb (very stringent as learnt) in the produced water to be discharged from our offshore platform. Can you pls advise on how to meet this limit and if there are any good references to go by in your installations? Pls help.

Thanks in advance.
TechV

 

[dcasto]

Check with Calgon Carbon and Puraspec.

 

[GarySCWSVI]

Take a look at this web site:

http://www.purolite.com/ProductID/19/FolderID/71/PageVars/Library/Products/ProductDetails.htm

This is information on a Chelation Resin for Mercury and precious metals removal.

Gary Schreiber, CWS VI
The Purolite Co.

 

[DedalusEnviro]

Gary gives an excellent tip. Iminodiacetic resins of the kind he alludes to have an intense affinity for Hg. Rohm and Haas makes one called Amberlite IRC 718 that will also work.

If you prefer a more conventional precipitation process, there is an organo-sulfur product called TMT that is capable of precipitating Hg down to extemely low levels. It's made by DeGussa. Here's a data sheet.

http://www.degussa-bk.de/asp/documents/239_Document.pdf

Dave Wichern

http://www.dedalusenviro.com

Science is a business of empiricism.

 

[THIOLSAMMS]

Try the web site stewardsolutions.com for directions to technology for this

 

[davefitz]

GE water sells metclear, and GE Zenon sells a bioreactor that reduces the Hg and SE etc to unmeasurable amounts. But the bioreactor woudl be the size of your offshore platform

 

[rocketscientist]

Try looking at the EPA information referenced in this Chemical Processing article:

http://www.chemicalprocessing.com/articles/2007/039.html

Dirk Willard

 

[siretb]

We have to do that on waste waters.
We use regular TMT15 precipitation PLUS ion exchange for safety
In theory TMT alone would do the job. But you have to be very careful, you may have colloids after the decanter
Also be careful about the Chloride content, it complexes the Hg.
If you have lots of mercury, think also that the resin cannot always be regenerated to full capacity. This is one more reason to remove the bulk of metals by precipitation first

 

[bimr]

There are several techniques for mercury removal. The selection of the best technology will depend on many factors including but not limited to the space available for the process, the water TDS, the mercury influent concentration, and the cost of waste disposal.

Gary gave a good tip on ion exchange. Wether ion exchange is practical or not depends on the factors listed above. Ion exchange will probably not work well if there is any oil in the water.

Sulfide precipitation is another commonly used process for mercury removal:

http://www.epa.gov/nrmrl/pubs/625r97004/625r97004.pdf

Chevron has a paper outlining a treatment approach:

http://ipec.utulsa.edu/Conf2006/Papers/Gallup_91.pdf.

It looks like Chevron is using thiosulfate. It is believed that the thiosulfate reacts with mercury to form mercury sulfides in a manner similar to that of the sulfide precipitation process. The thiosulfate process will be somewhat more expensive than others.