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Treating total phosphate in waste water treatment plant

May 17, 2009

Hi,
We have a iron phosphating and electro-polish line, we like to know what are the best way to treat this total P or total phosphate in our waste water treatment. We had tried calcium hydroxide and calcium chloride but usage a very heavy. We like to bring down 25 ppm to 8 ppm. Is there any possible ways.
Thanks

Arthur Koo
Employee - Hong Kong, China

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You might try using some alum instead of some of the calcium chloride.

Lyle Kirman

Lyle Kirman
consultant - Cleveland Heights, Ohio
May 22, 2009

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May 27, 2009

Mr Kirman
Thanks for replying my question.
I like to know what alum you are referring to. At what concentration needed to reduce the total Phosphate?
Thanks

Arthur Koo
- Hong Kong ,China

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I have heard of lanthanum sulphate being used.

This is a common issue in municipal sewage treatment. You might try some advice boards geared to that.

Dave Wichern
Consultant - The Bronx, New York
June 5, 2009

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Try Aluminum chloro hydrate (ACH). Reduce the lime or calcium chloride dosage by 50% and add 15-25% ACH. This should give you lower sludge generation while still meeting the phosphate limits.

Gordon

Gordon Djani
- Greenville, South Carolina
June 16, 2009

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By Alum, I mean aluminum sulphate, usually sold as the hydrated salt.

In combination with calcium, it should give better results than calcium alone. The best mix needs to be determined by jar testing, but for a starting point, I'd suggest reducing the calcium by half and replacing it with alum.

Lyle Kirman
consultant - Cleveland Heights, Ohio
June 19, 2009

Try a non-phosphate. The waste treatment issue will go away.

Joe McHenry
- Cleveland, Ohio
July 25, 2009