Sealing a Digester Platform

[jfrey414]

I have a circular stainless steel platform located in the center of a digester that is leaking gas. The culprit is the interaction of the platform plate and the rolled tube used to secure the membrane. In fabrication the plate was only stitch welded to the tube and we have attempted to seal the gap with sealant. We are unable to weld due to the combustibility of the gases in the tank and would like a more permanent solution. Currently there are only a few pin hole leaks. I am looking at a Sika product, Sikadur Combiflex" which utilizes a method similar to drywall taping. Sika's concern is the ability to adhere to the stainless without thoroughly scarifying the surface which brings into the combustibility of the gas.

1. Is there a different product/method that can be used to seal the joint?
2. Is there a method to eliminate sparking hazards when scarifying the steel?


Thanks for your help.

 

[Ron]

Consider using dry ice blasting to scarify. No sparking.