Xanthan

Numerous positive characteristics mean that the long-chain polysaccharide xanthan is a product that can be used universally. In baker‘s products, xanthan is responsible for pore structure, greater volume and an extended shelf-life. It is used in desserts, chewing gum and ice cream as well as in dairy and yoghurt products or fruit products to improve the mouthfeel. Xanthan is also frequently to be found in cosmetic lotions, creams, shampoos, liquid soap and toothpaste, in pharmaceutical recipes and animal feeds where it binds water or controls flow properties. But xanthan is not only used for consumer goods. An important application is also thickening drilling emulsions in the oil drilling industry.

This universal substance is the metabolic product of a specific type of bacteria. On an industrial scale, the bacteria are bred in large fermenters, and the metabolic products produced by the bacteria are subsequently harvested.

This is where GEA Westfalia Separator’s expertise comes into play. The actual process of recovery downstream of the fermenter takes place primarily in a 2-stage process with separators and / or decanters, whereby the first stage is for clarification and the second stage, namely the washing stage, is used for dewatering the xanthan as far as possible.

Two factors are particularly important in the separation process: the control of shear forces and explosion protection. Shear forces have a major impact on the quality of the longchain saccharide, and thus on the price of the product. GEA Westfalia Separator, therefore, uses a special design to ensure gentle product treatment and high throughput. Decanters of the TCA series for instance are used for this application.

Particular attention has also to be paid to explosion protection, as the solvents used are alcoholic and pose a danger of explosion. In this respect, GEA Westfalia Separator has been able to implement innovations focusing on customer benefit as a result of its many years of experience with explosion-proof processes; one method involves nitrogen blanketing of the machines.

In addition, GEA Westfalia Separator know-how guarantees maximum safety and maximum product quality. GEA Westfalia Separator has, of course, implemented the requirements specified in the new ATEX directive for decanters and separators. Several machines have already been successfully commissioned for this process in accordance with the ATEX directive. GEA Westfalia Separator is without doubt one of the leading suppliers of centrifuges for xanthan production world-wide and by far the major supplier for such centrifuges in Europe.