Experiences with small-perforation screens in the starch industry, particularly in potato starch manufacturing

Plate and fabric screens, especially those with small openings, have numerous applications as separation elements in diverse industries. The separation elements chiefly used in the starch industry are classified on the basis of make, material, and form (geometry) and width of aperture. The purposes for which the separation element is employed determine which type is used for the solution of a particular technical problem. By means of examples and employment data, the areas of application in the basic operations of starch processing are presented. The mechanically produced small-perforation plate screens with conical openings, developed for fibre extraction, pulp dewatering and finefibre separation in connection with jet washers, are described and their performance in respect of starch and dry substance content and advantages – simple and rapid assembly/dismantling and long operating periods – are discussed. The curved screens used in the corn starch industry, at present with slot widths of 75 m m, are likely to see further development of small-perforation plate screens to slot widths of 50 m m.