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DESLUDGING ACID ZINC PLATING TANK

 

Hello Everybody,

I am working on one electroplating plant of ammonium chloride acid zinc plating. Here the production rate or surface area treatment/plated per day is too high. There is regular increase in Iron content in the bath & we cannot stop our production. To remove this iron content we add Hydrogen Peroxide. This process creates lot of sludge/settlement. Which we are removing by our continuous filter system.

I have visited some automobile companies who use phosphating chemicals. There also continuous sludge formation takes place. They generally keep separate tank for settlement of sludge, in this tank continuous pumping of phosphating chemical from phosphating tank takes place & after settling of the sludge, chemical goes to filter press, where remaining sludge is also removed. Then this clear solution goes to main phosphating tank. This is continuous process & is very much important for higher & continuous production plant.

Is the same thing can be applicable to electroplating tank, by keeping one separate tank which will continuously remove iron by H2O2 & de-sludge by settlement, then filter & clear solution back to processing tank. If anybody knows about such system, please let me know.

Regards,

Santosh Zope
DWP - Dubai

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There are many different types of filters that can handle large quantities of sludge, including sand filters and continuous paper filters (not to mention filter presses). Yes, you could use a separate de-sludging tank but I've personally never heard of it because the shops I've worked with don't find it necessary.

I don't know why you are generating huge quantities of waste products unless parts are falling into the tanks from the racks and left there to dissolve. And if that is the case, it is utterly unacceptable regardless of production demands! Stopping the line if a part falls off the rack is the key to solving the problem of parts falling off the racks :-)

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