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Anybody use capacitive deionization for waste concentration?

I am an engineer who is working on developing capacitive deionization equipment, and was wondering if anyone active in the finishing industry has any experience/viewpoints on this technology. Essentially, this can take any relatively dilute ionic solution from a few ppm up to 5000-10,000 ppm(including many electroplating waste rinses) and create a treated (deionized) stream, and a concentrated stream. The concentrate takes us less space than the original waste, making it easier to treat/reuse. While a number of researchers mention electroplating waste treatment as a potential application for capacitive deionization, I haven't seen very many perspectives from the electroplating industry's side. So, does anybody use this sort of equipment? Are there any issues that would need to be solved? Or are existing waste concentration technologies (Reverse Osmosis, Electrodialysis, etc.) 'good enough'?

Lawrence Weinstein
R&D engineer - Bristol, Pennsylvania
July 7, 2011

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There is a company in China making this type of equipment for waste waters. It is used by companies with TDS limits to bring down the TDS from thousands of mg/L to less than a thousand mg/L. I haven't heard much about it lately though.

There is also a company in the US that makes capacitive DI systems. You can probably find them if you search Sabrex. They are in San Antonio, Texas.

Lyle Kirman
consultant - Cleveland Heights, Ohio
July 15, 2011