Mechanical engineering and mold construction

Lewatit® ion exchange resins for mechanical engineering and mold construction

 

Wherever metallic materials are processed, there are a large number of procedures involved that require water for cleaning or as a cooling or lubricating agent. This applies to sawing, drilling, grinding, degreasing and pickling of workpieces, electrolytic derusting, burnishing and etching, and in electroplating and electropolishing.

The demands on the quality of the water used can vary greatly depending on the area of application. The challenges posed by disposal, treatment or recycling of the resulting wastewater are just as varied.

Ion exchange resins from the Lewatit® product range make important contributions, be it in the softening or partial or complete desalination of the process water or in cleaning the wastewater or recovering reusable materials from this wastewater. For example, environmentally hazardous anions such as fluoride and cyanide can be removed selectively, as can heavy metals such as nickel, chromium, cobalt, iron and manganese. This method is widely used to clean pickling and acid baths. From an economic point of view, the idea of recovering precious and platinum metals such as silver, gold, platinum and palladium is particularly appealing.

The key requirements of plant operators are reliability and cost-effective operation. With their selectivity and regenerative ability, the high-quality ion exchange resins fit the bill perfectly.

Due to ever more stringent legal requirements, there is increasing economic interest in circulating rinse water while using mixed bed ion exchange resins to treat it. Electroplating operations provide a good example of this. Ideally, this procedure could even be used to make operating facilities completely free of wastewater.

In addition, ion exchange resins – often combined with filter elements for reverse osmosis – are indispensable wherever steam is used. As in thermal power plants, they ensure that water-steam cycles operate reliably and with little maintenance. This requires careful treatment of the make-up water, and also high-performance condensate polishing.