Product and equipment related causes of sugar losses in the beet yard

Quantitative considerations and interpretations concerning the causes of losses in the beet yard are possible only when the level of damage can be assessed exactly and when the elution characteristics of beets as a function of the damage level and other parameters are well known. Südzucker has developed a photographic method with an optoelectronic analysis to determine the level of damage of sugar beets for this purpose. Photos are taken e.g. when trucks are unloaded or during the transport of beets on conveyor systems. The level of damage can be assessed easily this way and meets the statistical requirements in relation to the number of subjects. The reproducibility of this method is acceptable. A correlation between the increase of the damage level as it occurs on the beet yard and the COD-level was obtained. The elution characteristics of beets darmaged up to different levels and beet particles were investigated in laboratory experiments. Operational conditions in the factory were determinated in flume and wash water (residence rime of the beets, pH, level of damage) and COD-levels were assessed. Consequently, the individual causes for the COD as it arises may then be calculated separately from the residence time and elution characteristics. The difference between the load assessed in this way and that as it occurrs in practice must be explained with the increase of beet damage with the system. Practical assumptions concerning their impact make it possible to elaborate an algorithm for a plant The comparison between the information inferred from the algorithm and the industrial experiences can give useful information about the influenee of changes in the working conditions.