VOC, ethanol removal with RO/GAC 1

[Moose11]

I am attempting to remove TOC, VOC, and ethanol from a process condensate steam for reuse as high pressure boiler feedwater. Our pilot work showss that wee get 75% removal (200 ppm down to 40 - 50 ppm) of TOC using RO membranes, with the remaining organics consisting primarily of low molecular weight VOC and ethanol.

Will a GAC column get us where we need? I am targeting less than 5 ppm TOC and this water will be re incorporated ahead of an existing demin/mixed bed train. System operates at 1250 psig including several turbine generators so organic acid loading will be a concern.

Any suggestions would be helpful regarding alternative treatment methods and and TOC feedwater limits.

Thanks

 

[GarySCWSVI]

VOC'S are not rejected well if at all by most membranes. Volatile organics are, in most cases, handled by GAC. However, I would recommend that one uses an adsorbent resin over GAC. Those resins can be regenerated and reused where GAC typically has to be replaced. There are many different types of adsorbent resins available. Identify the VOC's and then select an adsorbent resin that will handle it. Some of those are available as non-functionalized inert resins and some have some ion exchange functionality. Your resin manufacturers can provide information based on an analysis of the VOC's you are dealing with and recommend a resin of choice. My company, The Purolite Co., has a wide ranging selection of adsorbents to be used for TOC and VOC reduction.

Gary Schreiber, CWS VI
The Purolite Co.

 

[Moose11]

Gary
Thanks for the response. I believe we procure Purolite resin (GE Water and Process Tech). I just had a meeting and it looks like we will need to use this waste stream for high pressure boiler feedwater make-up.

Jeff

 

[oxilume]

Jeff,

First, what is the flow rate and pressure of your condensate?
I can absolutely guarantee TOC below detection limits with my ArcLight system (see:

http://www.oxilume.com).

However, I doubt if it will be cost effective, unless of course you need steam plasma(+5,000F).

On the otherhand, the system can be operated in the high flow mode for organic destruction. The 100 KW ArcLight can be operated to as high as 500 gpm.

The system was developed for removing water soluable organics from oil & gas produced water (maintain below 32 ppm as required by EPA, US Coast Guard, MMS, etc.). The system has shown complete destruction of MTBE in drinking water. It is being tested on Paint Booth water from the world's largest automobile manufacture, and on WSO in Uranium mining wastewater effluent.

Also, the system must be operated with a filter, such as Purolite's. If you would like, I can email a presentation to you.

Sincerely,
Todd




Todd

http://www.oxilume.com