No registration or passwords; no pop-up ads -- just aloha, fun, & answers.
(as an eBay Partner & Amazon Affiliate earns from qualifying purchases).
Home /
T.O.C.
Fun
FAQs
Good
Books
Ref.
Libr.
Advertise
 
Help
Wanted
Current
Q&A's
Site 🔍
Search
pub  Where the
world gathers for metal finishing
Q&As since 1989



-----

REMOVAL OF copper sulphate AND ZINC sulphate FROM WASTE WATER




HELLO,

WE ARE PICKLING COPPER AND BRASS SHEETS AND RINSING THEM WITH WATER AFTER PICKLING.

THIS WASTE WATER HAS copper sulphate AND ZINC sulphate WITH TRACES OF FREE SULFURIC ACID, IS THERE A PROCEDURE TO SEPARATE THE copper sulphate and ZINC sulphate FROM THE WATER.

THE PH OF THE WASTE WATER IS 4.

COMMENTS AND ADVICE REQUIRED.

THANKS IS ADVANCE

PETER MARKUS
- SINGAPORE
2005



Do you just want to remove the copper and zinc or do you actually want to remove the copper and zinc as sulphate compounds? The approach will differ significantly.

A nanofiltration system (using divalent ion separation capable membranes)will retain a high degree of the copper and zinc as sulphate compounds. If you are looking to remove them to WHO or Singapore standards, you would probably need to use multiple passes to achieve compliant levels of the metals. However, the free acid ions will pass readily through the membrane, so expect a low pH in the permeate of the system.

If you are looking to simply remove the metals as ionic copper and zinc, you would see a high degree of removal to the low ppm or ppb range with an ion exchange system utilizing a chelating resin, which is specific for heavy metals. Little pH adjustment would be necessary to the influent of such a system under this scenario, however care should be taken to allow for pH adjustment as necessary in case there is a slug of more concentrated solution gets intot he rinse system.

Lastly, and alternate to this would be to completely recycle the water in a packed bed ion exchnage system, where you would get 99%+ of the water back in the form of DI water, and be left with an enriched solution of copper and zinc (either in chloride or sulphate counter ions) in the regenerant, plus an alkaline sodium sulphate/sodium hydroxide waste originating from the anion column. Depending on the incoming TDS of the water, this could be an excellent approach for you to consider.

tom baker
Tom Baker
wastewater treatment specialist - Warminster, Pennsylvania
2005


See the other responses for an inquiry from India.

Juzer Jangbarwala
- Brea, California
2005




(No "dead threads" here! If this page isn't currently on the Hotline your Q, A, or Comment will restore it)

Q, A, or Comment on THIS thread -or- Start a NEW Thread

Disclaimer: It's not possible to fully diagnose a finishing problem or the hazards of an operation via these pages. All information presented is for general reference and does not represent a professional opinion nor the policy of an author's employer. The internet is largely anonymous & unvetted; some names may be fictitious and some recommendations might be harmful.

If you are seeking a product or service related to metal finishing, please check these Directories:

 
Jobshops
Capital
Equipment
Chemicals &
Consumables
Consult'g, Train'g
& Software


About/Contact  -  Privacy Policy  -  ©1995-2024 finishing.com, Pine Beach, New Jersey, USA  -  about "affil links"