New Corrosion Prediction software wins industry award

Our corrosion prediction company, Corrdesa LLC, in Atlanta GA, is growing and developing new technologies to help engineers reduce corrosion. Corrdesa has just introduced new easy-to-use software called Corrosion Djinn, see

http://www.corrdesa.com/technology/corrosion-djinn/

At the NACE 2017 Corrosion Conference in New Orleans Corrdesa received a Materials Performance Corrosion Innovation of the Year Award (see the list of prizewinners in Materials Performance. An article about the use of computational methods for corrosion assessment using a combination of methods including Corrosion Djinn and Finite Element Siemens Star CCM+ will appear in the April edition of Materials Performance magazine.

Even though the on-line Corrosion Djinn software http://corrosiondjinn.com is very easy to use, it represents an important advance for galvanic corrosion protection because it is based on calculating the actual corrosion current across the interface between two materials. This is a major advance on the old galvanic tables and specifications such as MIL-STD-889B, which often give completely the wrong answer because galvanic corrosion severity is determined by corrosion currents between materials, not their potential difference, ΔE. In fact, NAVAIR, the defense organization in charge of US Naval aircraft, is working on modifying MIL-STD-889B to base it correctly on current instead of ΔE, and Corrosion Djinn is the only prediction software on the market able to make this calculation without resorting to very complex and expensive Computer Aided Engineering methods.

 

Endangered Species

Periodic Table showing endangered species in red

Periodic Table showing endangered species in red

To download a PDF of this picture, click this link: PeriodicTable-updated. [This document, by the way, is an 8 1/2 x 11 glossy card that we printed up and took to a couple of recent engineering meetings. Every one of them disappeared in no time. If you want a few copies just mail us at lsolnick@rowantechnology.com. If you want a customized version with your own company information on the front and back, let us know and we can give you a price.]

We are all familiar with the table above. Some people vaguely remember it from long-ago high school chemistry lessons, and some, like me, refer to it every day. But all of us depend on it every moment of our lives, since the Periodic Table is the list of all the elements that comprise our world.  Everything in our bodies and everything we manufacture, from airplanes to cell phones to frying pans, must be made from this small collection of atoms, fewer than the colors of lipstick in the drug store.

All the elements in red are on somebody’s “toxic substances” hit list somewhere in the world:

  • In some cases it is the element itself (mercury (Hg), lead (Pb), cadmium (Cd), even zinc (Zn) and silver (Ag))
  • In other cases, a few specific compounds (boric acid, silicon oxide (crystalline silica))
  • And in other cases, almost every compound that can be used for manufacturing (nickel (Ni), chromium (Cr), cobalt (Co) compounds).

Starting with Europe and its REACH regulations, governments are increasingly basing environmental and health regulations on hazard, not on risk. In some cases they explicitly adopt the Precautionary Principle (as in Europe), while in others they bring it in the back door (as in California). The purpose of calling materials hazardous substances is to restrict their use or ban them, rather than to take the more rational approach of ensuring that they are used with proper regard for the workers or members of the public who come in contact with them.

What’s the difference between hazard and risk? A hazard is something that can be harmful – the electrical wires running throughout your home, the gas in your cooktop, the bus barreling down the road.  These are all hazards we live with every day.  But they only become risks when we work on the electrical wiring without turning off the power, or turn on the gas without lighting it, or walk out in front of the bus. In the same way “hazardous chemicals” do us no harm unless we eat them or breathe them. Their mere existence or proximity to us (your cell phone is full of them) is of no more consequence than electricity or gas or moving vehicles, or any of the other hazards that make modern life so much better than living in the Middle Ages.

Once you ban or unnecessarily restrict chemicals you end up, not with a safer, cleaner world, but with a world in which modern industrial societies can no longer exist:

  • Without Ni you would have no stainless steel – no stainless knives or cookware, no stainless medical or dental implements
  • Without Zn our cars, chain link fences, metal buildings, metal lampposts and highway barriers would rapidly turn to rust.

You even end up with total absurdities such as treating boric acid as a deadly toxin (look on the contents of your bottle of eye-wash some time), or of regulators trembling in fear over carcinogenic crystalline silica and then taking their kids to the beach for vacation (what do you think sand is made of?).

Banning a chemical means that you have for ever foregone every technology that could have existed because of it. Suppose we had decided in 1950 that silicon was hazardous and banned it, or done the same with phosphorus, boron and arsenic as people are trying to do now. No more I-Phones, laptops, garage door openers, digital watches, grocery scanners. But we could still have big, heavy, black and white electron tube TVs, and computers half as big as a house with less computing power than today’s pocket calculators.

REACH claims its purpose is to drive innovation.  But in the real world, there is no better way to destroy innovation than to ban the materials it depends on.

EPA Issues Stricter Hex Chrome Rules

Graph of CrVI Emissions from EPA National Emissions Inventory 2005

Graph of CrVI Emissions from EPA National Emissions Inventory 2005

National Emission Standards for Hazardous Air Pollutant Emissions: Hard and Decorative Chromium Electroplating and Chromium Anodizing Tanks; and Steel Pickling— HCl Process Facilities and Hydrochloric Acid Regeneration Plants

On September 19 EPA  published their final hexavalent chromium rules: Federal Register / Vol. 77, No. 182 / P. 58220 / Wednesday, September 19, 2012.   Click on link to download:

EPA Final Hex Chrome Rule, 9-19-2012

The table below summarizes the rule.

  New Limits Previous Limits
Decorative Chromium Plating:
Existing Sources 0.007 mg/dscm 0.010 mg/dscm
New Sources 0.006 mg/dscm 0.010 mg/dscm
Chromic Acid Anodizing:
Existing Sources 0.007 mg/dscm 0.010 mg/dscm
New Sources 0.006 mg/dscm 0.010 mg/dscm
Hard Chromium Plating:
Existing Sources   (small) 0.015 mg/dscm 0.030 mg/dscm
New Sources (small) 0.006 mg/dscm 0.015 mg/dscm
Existing Sources   (large) 0.011 mg/dscm 0.015 mg/dscm
New Sources (large) 0.006 mg/dscm 0.015 mg/dscm

 

These are the lowest hex chrome emission limits in the world.   Many platers , especially decorative chrome platers, have been meeting the existing limits with PFOS fume suppressants.  However, the new rule  bans the use of fume suppressants containing >1wt% PFOS, because it is a long chain perfluorinated compound that is persistent in the environment (PFOS used to be used in manufacturing Scotchgard and similar fabric stain repellents, but those products were reformulated some years back).  There are now short chain perfluorinated compounds on the market that have been successfully tested for fume suppression in chrome plating baths.  EPA claims that the new limits can be met very inexpensively, merely by increasing the amount of fume suppression surfactant in the plating bath.  However, recent testing shows that merely reducing the surface tension of the bath does not in fact reduce emissions.  This leaves platers with the only option of installing far more expensive scrubbers, which will be difficult or impossible for typical small plating companies to afford, especially in the present economy.

The Graph above shows the vast difference that this rule will make to hex chrome emissions.  Simply reducing power plant emissions of CrVI to 99.5% of their current levels would have the same effect as utterly obliterating the coating industry (and driving out all the industries dependent on it, which is most of them).

For more information see the NAS F website discussion of the new rule at http://www.nasf.org/nasf-news.php.