High pressure reactor (steel) used for ammonia production following the Haber process. Built in 1921 by the <i>Badische Anilin- und Sodafabrik AG</i> in Ludwigshafen am Rhein. Now reerected on the premises of the University Karlsruhe, Germany.
<a href="//commons.wikimedia.org/wiki/User:Drahkrub" title="User:Drahkrub">Drahkrub</a>
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<span class="int-own-work" lang="en">Own work</span>