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Pickling of steel rod

I am interested in pickling steel wire. Where can I find information on how to setup a pickle process and how to formulate the HCl solution.

Any help will be appreciated.

J Strauss
- Cape Town, South Africa
2006

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2006

Sir:
Usually steel pickling using HCl is done by a 50/50 mix of concentrated HCl (35%) and tap water to form about a 17% HCl solution. An inhibitor such as Parkin NEP 232 (at a concentration of one to three parts per 10,000) gives longer pickle life and protects the base steel. The usual temperature for pickling is about 20 deg. C to about 25 deg. C. There are exceptions to the temperature. Pickling time for average mill scale is about 15 minutes. As the iron dissolved in the acid increases the pickling speed also increases. At a certain point the available of free acid decreases and pickling speed slows. At about 12% iron (Fe+2) the pickling bath is "spent." In JoBerg there is an HCl recycling plant called Metsep.
Regards,

Dr. Thomas H. Cook
Galvanizing Consultant - Hot Springs, South Dakota, USA