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High sulfide Content in the Wastewater

I am working in an electroplating plant. Waste water treatment is one of my responsibility. Lately, the sulfide content in our wastewater is high. 1.3ppm sulfide(as S). I hope someone could help me as I do not know what is the cause of that, and how to remove sulfide from the wastewater. Thank you in advance.

Lee Hock Lee
- Singapore
2002

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If the sulfides are not coming from your process or your water treatment chemicals, then they may be coming from sulphate reducing bacteria in the water. In any case, the way to get rid of sulfides is to oxidize them. It is a fairly simple reaction and any common oxidizer such as sodium hypochlorite, or peroxide will work.

Lyle Kirman
- Newbury, Ohio
2002

Thank you for your advice, Mr. Lyle Kirman.

Lee Hock Lee
- Singapore
2002

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1) The treated waste water in our sludge settling tank usually turn blackish after a long period of holiday (more than 3 days). Or if it remains stagnant for a long period of time. Not only blackish, but strong sulfur like smell exist.

2) How to remove Sulfide (as S) content in waste water? I appreciate very much if someone can offer a solution to the above problems.

Lee Hock Lee
- Singapore
2003

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It's probably less practical to remove the sulfur than to not put an excess amount in in the first place. So, how did it get there, and do you restrict sulfur additions to secondary treatment, in a scavenger role, or are you adding sulfur as part of primary precipitation.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

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It sounds like your wastewater is growing sulphate-reducing bacteria. Since these are anaerobic bacteria, they can be avoided by either oxygenating the water, or by adding a small amount of oxidizer like bleach ⇦ bleach/sodium hypochlorite in bulk on eBay or Amazon [affil links] or peroxide.

Lyle Kirman
consultant - Cleveland Heights, Ohio

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I thank Mr. Ted Mooney and Mr. Lyle Kirman for their advice.

Lee Hock Lee
- Singapore
2003
2003