Cane - Import export

Cane sugar is produced by means of technologies rather similar to those used in a beet sugar plant that are also fully mastered by DSEC. Sugar cane is however a totally different plant compared to sugar beet: whereas sugar beet is sowed and can be harvested after +/- 6 months, cane takes longer to grow but grows back after it has been cut and can therefore be harvested several consecutive years (4 to 6) before being replanted. Cane can be cut either manually or mechanically before being directly processed in the mill. Cane plantation location in relation of the plant is of paramount importance so as to reduce sugar losses by the degradation of the plant after cutting as well as to minimize logistic costs. DSEC will select the most appropriate methodology for extracting the juice from the cane after its first shredding. The extraction operation will be performed using mill tandem or cane diffusion while additional mills will press the residual solid (bagasse) in order to increase its fiber content while additional mills will press the residual solid (bagasse) in order to increase its fiber content. Pressed bagasse will be used as fuel for the plant combined heat and power generation that will generally export electricity on the public grid. The choice between mill tandem and diffuser will be highly dependent on plant capacity, cane characteristics, expected extraction performances and plant general concept.

The fermentable carbohydrates from sugar cane or sweet sorghum may be directly utilized in the form of cane juice or in conjunction with a sugar factory from molasses. Cane juice is prepared by crushing / diffusing the raw cane and after extraction, clarifying with milk of lime and sulfuric acid to precipitate the inorganic fraction. The extract may then be evaporated to the desired concentration and used directly in the fermentation. A major disadvantage in the utilization of sugar cane juice is its lack of stability over extended periods of storage. Molasses is the non-crystallizable residue remaining after the sucrose has been crystallized from cane juice. This heavy viscous material is composed of sucrose, glucose, and fructose at a total carbohydrate concentration of 50-60 %. Molasses may be easily stored for long periods of time and diluted to the required concentration prior to use.