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Corrosion Control in the Corrosive Environment

February 21, 2017 |

G1 chart for ISA 74.01The goal of every wastewater plant, electronics manufacturer, and other facilities that either generate corrosive gas or are sensetive to corrosive gasses is to get to a Mild or G1 level as defined by ISA 71.04:2013 in order to ensure that there are no ill effects of corrosion within their facility or that harmful molecular compounds are not exhausted outdoors.  But before you can implement a corrosion control method you must first evaluate where you are and where you want to be.

 Measurement and evaluation of your facility or space within your facility would start most liekly with a corrosion coupon.  That will determine the general level of corrosive molecular compunds/gasses and then you could do more testing of specific compounds if needed.  The corrosion coupon testing follows procedure ourlined by the ANSI/ISA 71.04:2013 standard which defines two groups of gasses and then outlines the concentration limits of these gasses.

G2 Chart for ISA 74.01 corrosive environmentsThe two groups of gasses are Group A and Group B, with Group A gasses being known to have synergic properties meaning that the presenece of eachother amplifies their corrosive effects, and Group B gasses are unknown whether they have synergistic/amplifying effects.

Group A Molecular Compounds are:

  • Hydrogen Sulfide
  • Sulfer Dioxide
  • Sulfer Trioxide
  • Chlorine
  • Nitrogen Oxides

Group B Molecular Compounds are:

  • Hydrogen Flouride
  • Ammonia
  • Ozone

G3 Chart of ISA 71.04 corrosive environmentsIf these gases are above the Harsh or G3 concentration, then the space is determined to be at GX or Severe corrosive environment.  The strange thing is it is much easier to go from GX to G3, than from G2 to G1.  This is the paradox of Molecular filtraion (sometimes refered to as Carbon filtration) when compared to Particle Filtration.  This is driven by the fact that particles have a tendancy to agglomerate, but gasses do the opposite and spread out as far away from eachother as possible.  

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Many corrosion control projects either get over-engineered and expensive to implement, or are under-engineered and hastily installed so they fail.  Either way the facilty owner/manager is left with a distrust of carbon and molecular filtration.  We specialize in doing the hard part (testing) first and define clear goals, then match them with the proper carbon sorbent (we have about 60) so that the project goes as planned and doesn't cost any more than necessary.

Please contact us with specific questions or if you'd like us to come out and meet on-site we have relationships all over the globe to get you in contact with a local molecular filtration expert to get control of your corrosive environment!

Tags: IAQ Corrosion Control Carbon

Written by Ben Klawitter