Hello rajpal,
Although I have never actually used the powder coat process, I am
somewhat familiar with the finished product and the application. My
first thought when I read your question was that "overspray" or as you
say "waste powder coating" should be recycled. I found the following
information which confirms my understanding of the process:
http://www.pfonline.com/articles/080305.html
And since it is a dry powder, most powder coating overspray (up to
98%) can be readily retrieved and re-used. The unused powder is
reclaimed by a recovery unit and returned to a feed hopper for
recirculating through the system. The waste that results is
negligible, and can be disposed of easily and economically.
The powder spray booth is designed to safely contain the powder so
that overspray cannot migrate into other areas. The entrance and exit
openings must be properly sized to allow clearance of the largest
product part. The airflow through the booth must be sufficient to
channel all overspray to the recovery system, but not so forceful that
it disrupts the powder deposition and retention on the part. If one
booth is to be used for multiple colors, the booth interior should be
free of narrow crevices, seams, and irregular surfaces that would be
difficult to clean, especially if collected overspray is to be
recycled.
The powder recovery systems make use of either cyclones or cartridge
filter modules that can be dedicated to each color and easily removed
and replaced when a color change is needed. Equipment manufacturers
have made significant design improvements in powder spray booths that
both allow color changes to be made with a minimal downtime and allow
the recovery of a high percentage of the overspray, which can raise
powder use to nearly 100%.
You can see from this that it is standard industry practice to recycle
overspray. Your bulk "waste powder coating" should be able to be used
by anyone who has a requirement for the exact colors you have in
stock. However, I would think that you would have to somehow assure
the buyer of the quality/purity of your product.
Thanks for your interesting question, Redhoss |
