plating, anodizing, & finishing Q&As since 1989
Waterless Phosphating Process?
August 26, 2010
WE ARE FACING POLLUTION PROBLEM DUE TO DISCHARGE OF PHOSPHATING CHEMICALS. IS IT POSSIBLE TO HAVE EFFECTIVE PHOSPHATING PROCESS WITH LESS WATER OR WATERLESS OPERATION.PRAMOD KUMAR
CONSULTANT - MUMBAI, INDIA
August 31, 2010
Disposal of phosphating sludge, use of nitrite and heavy metal ions such as nickel as accelerators are the major environmental problems in a phosphating line.
Zero waste phosphating processes are available commercially.
I am not sure about whether any company is marketing phosphating gel (like the one used for passivation of stainless steel) which can be easily applied on the metal surface and wiped off after the desired period.
T.S.N. Sankara Narayanan
- Chennai, Tamilnadu, India
(ed.note Nov. 2017: The good doctor has a fascinating blog at https://advancementinscience.wordpress.com)
September 11, 2010
Dear Mr. Kumar,
Yes, zinc phosphating is very good process to enhance corrosion protection and adhesion before painting, but the sludge and other heavy metals are the main problem to the environment nowadays.
Now, there are many reputable chemicals suppliers had introduced non-phosphating pre-treatment for pre-painting with environmental friendly, there are containing non-toxic material like: Cr3+,Silane or Zirconium.
Then no-sludge or very less sludge formation that you can filter out.
The performance almost close to zinc-phosphate properties, in term of corrosion resistance and adhesion.
You can use the same machine but a little bit modification on the step.
Try to contact your reputable chemicals supplier in your city or country to help you.
process chemicals supplier - Jakarta, Indonesia