Removing inerts with steam?

[hollerg]

I need to change how five vessels are air-freed*. The current procedure drops the non-condensable concentration to at least 10% and perhaps, < 1%. Once cleared of non-condensables, this aqueous process operates at 200 F continuously without venting. The reactor has a partial jacket (~ 1/3" of the side) which could have low pressure, atmospheric steam applied. I plan to steam out the vessel but I doubt the visual appearance of the steam will be reliable indication of the gas concentration in the plumb.

I would appreciate suggestions on who to contact for a portable instrument/device to test the steam plumb. Even better if it is suitable for an electrically classified area. (O2 meter?, absolute humidity measurement?, ??)

Since I do not have an intermediate nozzle, am I better connecting the steam to the top of the vessel and down-flow, or configuring the bottom outlet to ingress steam and egress steam and condensate?

* Currently we fill to the top tangent line,(16,000 gal, w/ 1.5:1 H/D ratio) and sweeping the residual head-space with a much heavier halogenated gas.

 

[Compositepro]

The temperature and pressure in the head of your reactor can tell you what you want. However, the temperature, and therefore the concentration of non-condensables, will likely vary in different areas of the head space. In steady state conditions, the temperature of any probe in the head space should be at the local dew point. The dew point tells you what the partial pressure of water is surrounding the probe. Any additional pressure is due to non-condensables.

It is not clear from your post as to whether your vessel is sealed and operating at sub-ambient pressure or vented, in which case there must be non-condensables in the head space.

If you are steam purging the vessel, then all the non-condensables will be gone when the coldest spot in the reactor is 100C.