Strip lead based paint from Cast iron railings. 1

[corrosionman]

I run a "Shot Blast and Paint" workshop and at short notice I am trying to decide if it is possible to totally remove paint from 2000 sq mtrs (actual surface area) from cast iron railings on a Victorian Bridge.The rails would be dismantled and moved to our spacious workshop for paint removal, any metalwork repairs will be done before everything is repainted and the rails then erected again on site. Our original idea of conventional grit blasting would make lead dust.
Dipping in a tank of paint stripper will be slow and produce lead sludge, and we'd still need to grit blast before repainting them.
Maybe we could strip the paint in an oven before blasting to repaint and I guess this will make a lead ash ?

I would greatly appreciats comments on the use of dipping tank or an oven as alternative to conventional grit blasting.
Corrosionman

 

[mcgyvr]

Abrasive blasting is regularly done to remove lead based paints provided you use methods like certain respirators and ventilation systems. You need to consult your health and safety codes in your area to determine the amount of protection required. OSHA/NIOSH
Dry ice blasting might be something to look into also.

 

[unclesyd]

We cleaned a lot red lead primer and top coats from machine parts using a Pyrolysis Oven from Pollution Control Products.
Everybody was happy since we collected the bulk of the residue in a pan in the oven. A lite dust blast in the blast room finished the job. There was no problem as we collected the blasting dust from the cyclone on the recycling system.

http://www.pcpconline.com/index.html

 

[swall]

What about lead oxide fumes from the burn-off?

 

[unclesyd]

In the Pollution Control ovens any lead oxide formed would fall on the pan under the parts being cleaned.
The atmosphere in the oven stays slightly reducing until the very end of the cycle. There are no fans in chamber therefore no entrainment of particulate. We clean equipment containing polymers with additives TiO2, Kaolin, CaCo2 and we have never found any traces of these in the off gas. The circulation in the chamber is controlled by water sprays. The chamber has a max temperature of 900F. O2 is around 1% in the beginning and end of the cycle.
During our cleaning of the machine parts no Lead or Chromium, Chromate wash primers, were found in the off gas.

 

[swall]

Now that was a great post,unclesyd. I had been contemplating the burn-off of powder coat racks in our pyrolysis oven, with a heavily zinc loaded epoxy powder. No one could give me a straight answer that was technically sound concerning zinc oxide fumes.