Rouge in pharmaceutical water 2

[kellys13]

Am having a discussion regarding our USP water for injection distribution and storage system.

System currently meets USP compendial requirements for water for injection (WFI). It was installed in a GMP fashion, 316L SS throughout (15Ra internal finish) (cleaned, degreased, passivated prior to startup). This is a hot system (80C).

Questions:
1) Will blanketing WFI storage tank with N2 increase the rate of rouge formation throughout the distribution system?
2) Should the initial passive layer be viewed as a dynamic layer, fluctuating depending on the amount of dissolved O2 in the liquid stream, or a single starting point from which degradation occurs?

 

[metengr]

Interesting information. This might be of interest regarding rouge in the BioPharm Industry;

http://www.mecobiopharm.com/solutions/rouging_paper.pdf

 

[EdStainless]

1) yes
2) yes
Can you monitor redox potentials at various points in the system?
As temperature, pressure, flow, pH, oxygen potential and phase of the moon will all effect the Fe solubility, and hence the tendancy to form rouge.
I could go on, but the problem is that most people have no monitoring system. They don't know when and where the rouge starts. They don't know what process variables are trigering the mobility of the rouge.

The fact is that the rouge is more stable than the metal. If it is staying put and not reacting with or coloring your product, then leave it there.

= = = = = = = = = = = = = = = = = = = =
Corrosion, every where, all the time.
Manage it or it will manage you.

http://www.trent-tube.com/contact/Tech_Assist.cfm