Aloha, fun & authoritative answers -- no cost, no registration, no passwords, no popups
(as an eBay Partner & Amazon Affiliate we earn from qualifying purchases)

Where the
world gathers for metal finishing
Q&As since 1989

-----

Ammonia reduction in plating wastewater

Hello, I am a waste water tech and I have a waste stream that contains NH₄OH & H₂O₂. I am looking for any ideas on pretreatment before I discharge it to the mainstream waste flow. Currently I am using sodium metabisulfite, but I am concerned about how I can effectively break the ammonia complex and not pickup any other metal precipitates.

Thanks for your replies

James miller
- Phoenix , Arizona
1999

1999

I assume we're talking about a waste stream from plating. Both peroxide and ammonia can be removed by boiling, although this can be impractical considering rinse water volumes, and the ammonia may need to be recaptured again with a fume scrubber anyway.

My limited experience is that ammonia cannot be effectively disposed of with chemicals. Rather than pretreatment, what may be necessary is post treatment. That is, after you have removed the bulk of the precipitated metals with hydroxide precipitation and clarification, hit the remaining stream with DTC and an organometallic co-precipitant, and filter it. Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

(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: