Hello Chaps,

we're tendering for a generator inspection where the turbine is driven from geothermal steam

I have a lingering memory from university that copper, that copper, or at least the silver within the braze alloy used join the sections together, can be damage due to effects from hydrogen sulfide, methane and ammonia present in the atmosphere.

but ... I can't find any reference to it ! do I have a false memory ?
?

tony

 

I'm wondering why you are not using heat exchangers to sidestep the problem with chemicals in the steam. I doubt that using steam directly from the hot minerals is ever done. Heat exchangers, no matter their composition, would likely also be corroded eventually, but they could be considered sacrificial items compared with turbines and blades.

 

Hi Mark,

Your right, the turbine is protected; My concern is the general atmosphere and whether there is a risk to the brazing alloy on the generator.

I did take some advice From TWI;

Because of the insulation used on the generator, we can't exceed ~120deg rise so we don't need to worry.

Tony.