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Wastewater treatment created "peanut butter" sludge.Help!

I'm not the man in charge of taking care of Waste Water treatment at my facility, but take great interest in its problems. To make a long story short, the Clarifier must not be doing its job as well as the rest of our "turn key" operation. I'm sure it's something we are doing wrong, as the company we bought it from has been very informative and helpful as needed. When our wastes come out of the final process, (from zinc plating on rack and barrel platers) it resembles peanut butter instead of the clean, clear liquid it is supposed to resemble. If there is anyone out there who could offer some advice we could sure use it before it shuts us down. Thanks for any help you can give.

James D. Browning
- Oxford Mississippi

Hi James. The first step is to take a sample of this effluent, run it through a filter paper in the lab, and then analyze the filtrate for whether or not it is in compliance. Then you know whether your chemical treatment is removing the dissolved materials or not. If it is not, then you start determining what is not amenable to your chemical treatment; if it is, you start looking at your solids-liquid separation strategy. Best of luck.

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


Peanut butter...sounds pretty grim. If, after you do what Ted suggests, you find you are out of compliance, there are several obvious things to check.

First, are you adding flocculant to coagulate the solids? If the system is set up with an automatic flow sensor that regulates the polymer addition? Is the polymer actually reaching the system? (Line could be plugged) Second, check the precipitation pH to see if it is grossly wrong. (A good value is 9.0 - 9.5, generally) Use a handheld meter; don't rely on the panel readings. Lastly, make sure there are no concentrated cleaners being fed into the system.

dave wichern
Dave Wichern
Consultant - The Bronx, New York

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