Vermiculite

Hello All,
I was in Dusseldorf last week and ý have discussed with some people about insulation of galvanise bath for galvanising of steel.They advised me to use vermiculite. However ý know this material contains some asbestos inside and it is dangerous for health. Do anybody know about the insulation materials like that?
Best regards.
murat

Murat

Hello murat,

Heat loss from liquid zinc baths occurs by both convection and radiation.

I am told that pipe galvanizers typically use a layer of molten flux over a large portion of the surface of the zinc bath and that this significantly reduces heat loss. Pipe galvanizers have also observed that a layer of molten flux improves the process by reducing coating defects.

You may wish to experiment with this technique but of course tight control and much caution is recommended.

Kindest regards,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com

Vermiculite is a very common type of insulation used on galvanizing preocesses to avoid zinc oxides
( dross )and heat losses.

No health damege has been dectected in any of the many companies that uses it since it does not transform , it just stays and mixes with the zinc oxides to be removed after a period of use.

Some carbon powders are use for the same purpose but vermiculite is still the must common used

Eduardo Anaya
Senior Consultant
INDEPA S.C.
Mexico City
Tel(011-52)555-407-7451
This email address is being protected from spambots. You need JavaScript enabled to view it.

The National Institute for Occupational Safety and Health (NIOSH) section of the Centers for Disease Control and Prevention (CDC) in the US has much to say about asbestos fibers contaminiting vermiculite mined near Libby, Montana. Mining stopped at the mines near Libby in 1990.

NIOSH states the following about vermiculite contamimated with or presumed contaminated with asbestos.

"If the vermiculite is known or presumed to be contaminated with asbestos, NIOSH recommends the following general guidelines for limiting asbestos exposure:

* Avoid handling or disturbing loose vermiculite
* Isolate work areas with temporary barriers or enclosures to avoid spreading fibers
* Use wet methods, if feasible, to reduce exposure
* Never use compressed air for cleaning
* Avoid dry sweeping, shoveling, or other dry clean-up methods
* Use disposable protective clothing or clothing that is left in the workplace. Do not launder work clothing with family clothing
* Use proper respiratory protection.
* Dispose of waste and debris contaminated with asbestos in leak-tight containers in accordance with OSHA and EPA standards."

The you can read all about this at:

www.cdc.gov/niosh/docs/2003-141/

Kindest regards,
Peter J. Stewart-Hay
Principal
Stewart-Hay Associates
www.Stewart-Hay.com