Carl von Linde
Carl von Linde made industrial refrigeration and the liquefaction of air practical, and founded the company that still bears his name. Born in Berndorf, Bavaria in 1842, the son of a Lutheran pastor, he studied at the Zurich Polytechnic under Rudolf Clausius, one of the founders of thermodynamics, and was expelled for taking part in a student protest before completing his degree. He worked in locomotive engineering, and in 1868 became a professor at the new Technical University of Munich, where he taught thermodynamics and studied the theory of refrigeration. Existing ice-making machines were inefficient and used unpleasant working fluids. Linde published a theoretical analysis of refrigeration cycles in 1870-71 and then built machines to match it, patenting an ammonia compression system in 1876 that was far more efficient than its rivals. His first customers were breweries. Bavarian brewing depended on lager fermentation at low temperature, which had confined it to winter and to ice cut from lakes; Linde's machines made year-round brewing possible, and the Spaten brewery in Munich was an early adopter. Meat packing, shipping and food storage followed, and refrigeration reshaped world trade in perishable goods. He founded his refrigeration company in 1879 and returned to research in the 1890s. In 1895 he built an air liquefaction plant using the Joule-Thomson effect with regenerative counterflow cooling — repeatedly using the cooled expanded gas to pre-cool the incoming compressed gas until the temperature falls far enough for liquefaction. In 1902 he developed a rectification column to separate liquid air into oxygen and nitrogen. Cheap industrial oxygen made oxyacetylene welding and later steelmaking possible on a new scale. He was ennobled in 1897 and died in 1934.
- Lived: 1842 CE – 1934 CE
- Nationality: German
- Roles: engineer, inventor
