Vice President, Gas Programs IWDC
There’s a famous bar in New York City called McSorley’s Old Ale House. It’s been in lower Manhattan for a very long time. “We were here before you were born” says the window, in very small print, and you might even miss it on the way in. Many of us have been in this business for a long time, but the production and commercial demand for industrial gases goes back further, also before we were born.
Most of the major industrial gas companies have their roots in the late Nineteenth Century, when the earlier discovery and identification of the elemental gases created an opportunity for commercial development. The company names we know well… Air Liquide, Linde, Airco-BOC, Union Carbide-Praxair and even Messer and AGA can trace their roots back to one of four processes: the liquefaction and distillation of air; the electrolysis of water creating hydrogen and oxygen; the production of calcium carbide to produce acetylene for portable lighting, and a few short years later, the ability to mix and ignite oxygen and acetylene safely, producing a flame temperature hot enough to cut steel.
At a recent industry meeting, a question was posed to the group, “Who perfected the air separation process?”. A number of perplexed looks followed. The question was really based on removing some of the mystery and show this technology has been around for a long time. So if you’ll join me in the “way back machine”, think about the state of the world around 1870. Narrowing it down a bit, think about food freezing and refrigeration… there really wasn’t anything besides ice, and there was no commercial ice manufacturing, just harvesting ice. Ice was cut into large blocks during the winter in colder regions, and shipping it long distances wrapped in sawdust, blankets and wood crating. Surprisingly, our ancestors got pretty good at this… ice was transported by train from New England and the Northern Plains, and extending the season, by ship from northern Canada to places like New Orleans. If you were willing to pay enough for it, there were often supplies remaining well into the fall. But as you might imagine, ice was expensive!
At the same time, the scientists and engineers at the time determined that foodstuffs spoiled faster in warmer conditions. In particular, the German and Czech brewers recognized that they might extend their beer production well into the spring and summer if they could create an economical way to keep it cold. The basics of thermodynamics evolved in the mid 1800’s, but using the knowledge practically was a challenge. In this case, could this knowledge be used to manufacture ice, and if so, how?
The secret lied in the work done by the scientists Joule and Thomson, who discovered that a compressed gas cooled as it expanded. But it took a long evolution in manufacturing and materials to use this discovery. Carl Linde, working in Germany, developed what was probably the first successful air liquefier, using a large air compressor and a tightly insulated discharge line, containing a “Joule-Thomson Valve” that acted as a nozzle and allowed the air to liquefy. It was a remarkable commercial development, in fact, one of the first commercial machines was exhibited at the US Centennial Exposition in Philadelphia in 1876, and the machinery still exists in the Smithsonian collection in Washington. Linde’s process was so transformative to the German beer industry that the Kaiser conferred the “von” title to Carl Linde’s name.
But all wasn’t perfect. The same research in thermodynamics led to investigations in the use of other gases, most notably ammonia. In fact, in less than fifteen years, ammonia became the preferred methodology for ice, because it could be run in a closed cycle… the precursor of our modern refrigerators and freezers. At almost exactly the same time in France, Georges Claude developed a similar air separation process to Linde’s. Both Linde and Claude didn’t abandon their efforts after their machinery was displaced by ammonia plants. They each created the beginnings of cryogenic distillation in the 1890’s, both patented their designs, and began the licensing and sales of this technology between 1903 and 1905, under the Linde and Air Liquide names, first in Europe and rapidly expanding to North America. The process found a ready market in the Bessemer steel process that was really economically viable with lower cost, high purity oxygen… and the rest is history.