Process water from galvanic and surface treatment is often a complex cocktail, containing heavy metal salts, mineral acids, alkaline degreasing compounds and other surfactants. In many cases, this kind of waste water is treated conventionally by physical chemical methods. Chemicals like lime milk, iron chloride, aluminium chloride, acids and leaches are used to precipitate and flocculate metal hydroxide sludge. After separation of the sludge the water can be disposed of into the public sewer, observing official directives. Since the water is loaded with salts and heavy metals usually careful monitoring and reporting of water qualities to the water authorities is necessary. Operation costs of such a water treatment system are determined by a heavy workload and extensive chemicals consumption.

In 2008 Gebr. Kemper Metallwerken GmbH in Olpe decided to replace their physical/ chemical treatment system by a modern VACUDEST® vacuum distillation system for feasibility reasons. The evaporator with a capacity of 1,000 l/h is able to treat rinsing water from a degreasing system, loaded with degreasing agents, as well as backwash water from ioni exchanger regeneration, loaded with copper salts and sulphuric acid. In the VACUDEST® vacuum distillation system the process water is evaporated, contamination stays in the evaporation residue, thus distillate is very soft, virtually free of hydrocarbons and free of salts and heavy metals.

Gebr. Kemper Metallwerke GmbH is satisfied with their decision to replace chemical/ physical waste water treatment and invest in a VACUDEST® vacuum distillation system.

The distillate is far too valuable to dispose of, we recycle it into our process and can thus reduce fresh water consumption by far more than 90 %. In addition we have a zero discharge production
States Ludger Sondermann, head of the project management department. In fact, since installed in 2008 not only 5,000 m³ of process water have been treated feasibly, also nearly the same amount of fresh water could be saved. Authorisation for waster water disposal into the public sewer system and monitoring and reporting of water qualities to the water authorities is superfluous in the meantime, thus Kemper has multiple cost saving effects using H2Os smart ideas for clean water.