metallurgy for Steam Coils in a Sulphur Pit

Tantalum tube will always work: It behaves as glass and therefore does not get attacked by any acid, as far as I know, and behaves as a metal, because well, it is a metal.

Proposal of tantalum is good. But in your country how is the relative cost of tantalum, titanium and hastelloy ?

Well, I think hastealloy is the least expensive. The last time I had to decide between Tantalum and Titanium in some fifteen years ago, tantalum was the more expensive, however, I needed it for a very special application that needed reworking of the standard off the shelf product anyway. So I am not informed at this time between the two, although I would still think that Tantalum is the more expensive.

If money is no object, you could always use titanium.

Hastelloy C-276 is also used in these nasty places.

Never used tantalum, myself.

Either titanium or hasteloy would work; however, 316L SS is more readily available and less expensive in most parts of the world.

Just be sure to keep the coil free & clear of condensate, or it does not stand a chance between the sulphur on the exterior of the coil and the condensate from the inlet.

Good luck!

From my general understanding of materials, and from your statement that 316L is not available in the market, have you check the suitability of using 321 instead of 316L?

Hope this is not too stupid answer to your question!!

In general, 321 SS can (not all, but almost) replace 316 and 316L when 316 series is not proven improper (only shortage or urgent case)!!

I have had good results in sulfur rich, reducing atmospheres where nickel and copper content of metals causes "delamination" of 304 and 316 by using type 309.

www.arcmelt.com They have some papers written pertaining to high sulphur environments.