Conductivity and Temperature Recorder

Consideration has been given to the effect of vacuum pan circulation on sugar quality particularly with reference to filterability. It has been suggested1 that the introduction of a mechanical circulator, or stirrer, would enable the process to be carried out within closer temperature limits, so that the occlusion of undesirable substances could be prevented. In considering the possible installation of a circulator, the likelihood of the massecuite short-circuiting into the eye of the impeller presented itself. It was considered that a movable sleeve, located within the downtake and rising as the level of the massecuite in the pan rises, would ensure that the heated massecuite could be constrained to approach the surface more regularly and short-circuiting would thus be avoided. A similar idea was proposed by Waddell.2 Arrangements were therefore made in 1964 to install such a sleeve in an "A"-massecuite pan at Illovo. The experiment however proved inconclusive as the conditions under which sugar was boiled were too erratic, and examination of the data obtained showed that too maay variables existed for a complete analysis of the results. It was consequently agreed upon that before continuing with any further experiments along similar lines, an examination should be carried out into pan boiling as normally practised in Natal to obtain more detailed information concerning techniques, circulation criteria and other phenomena.