Q. How do I go about treating wastewater containing heavy metals? S. T.
A. A complete answer to your question would take many pages and is beyond the scope of this column. There are at least two areas that have to be addressed when answering your question: What is the chemistry of treating heavy metal waste streams and how can you obtain the training to perform the waste treatment? Since your e-mail did not mention which area you are interested in, here is some information on both areas.
There are a number of publications that discuss the chemistry and technology of wastewater treatment. Three such publications are: The Operation and Maintenance of Surface Finishing Wastewater Treatment Systems, Clarence H. Roy, American Electroplaters and Surface Finishers Society, 202-457-8401, www.aesf.org; Plating Waste Treatment, Kenneth F. Cherry, Ann Arbor Science Publishers (out-of-print but can be found by searching the internet); Electroplating Wastewater Pollution Control Technology, George C. Cushnie, Jr., Noyes Publications (also out-of-print but can be found by searching the internet).
If you are interested in operator training, an excellent correspondence program is available from CSUS Foundation; Office of Water Programs, CSU; Sacramento, 6000 J Street, Sacramento, CA 95818, 916-278-6142, www.owp.csus.edu.
Regulations do change frequently and you can’t rely on information published even a few years ago. You must check with your local regulators to learn the latest waste treatment requirements.
Our expert, Art Kushner, says yes, you can color stainless steel, but it is not a process that is typically performed in a plating shop. Read more about his answer.
An overview of decorative and hard chromium electroplating processes.
The reasons for installing an in-house cold blackening system are many and varied.