The Koninklijke Nederlandse Zoutindustrie (KNZ) is a former Dutch chemical company which was established June 18, 1918. The mining of salt started in 1919 in Boekelo, a small town at the end of the present local museum railway line in Haaksbergen. The salt, dissolved in brine, was tapped from a depth of 325 meters. In 1931 a chemical factory was raised in Boekelo for the production hydrochloric acid, bleach, chlorine, and caustic soda.
The “Zoutindustie” tank wagon was built in the same year as the factory for the transport of produced hydrochloric acid and bleach. The local museum railway line in Haaksbergen owns the wagon since 1980. In 2011 a thorough revision took place: the braking system was overhauled, the wagon was painted black and final signage and lettering was applied with the appropriate inscription “Zoutindustrie” on the boiler. The “Zoutindustie” tank wagon is regularly seen as part of historic freight trains running on the museum railway line.