New analysis technique in the chemistry laboratory facilitates search for trace elements

A new analysis technique is now being used in the chemical laboratory at Salzgitter Flachstahl. A special method of high-performance chromatography is proving particularly effective for determining low levels of substances in complex mixtures.

This is important when investigating rolling oils used in the manufacture of cold-rolling emulsion. Rolling oils contain a variety of different substances, which are present in various concentrations. They have a major influence on the cold-rolling emulsion and thus on the rolling process in the tandem mill and the cleanliness of the resulting cold strip. Thanks to this new analysis method, over a period of hours, it is now possible to separate the oil into individual groups of substances. The additives, emulsifiers, tensides, etc. in the rolling oil can be separated out and subsequently identified. This provides a distinct "fingerprint" of the oil. Similarly, this type of analysis can be used to prove that the oil does not contain any forbidden substances. In future, certain emulsifiers will be banned from rolling oils. This was taken into account with the switch to a new cold-rolling emulsion in the tandem mill. No forbidden substances have been found in the new rolling oil, even when using the new method of high-performance chromatography.

In addition to analyzing rolling oil and rolling emulsion, the new method can also be used to monitor the degreasing baths of hot-dip galvanizing plant 2. Whereas, in the past, it was difficult to determine exact contents, precise bath analyses are now possible. Since sample processing is now faster, this improvement also saves time.