Pneumatic agitation of high grade masseccuite in a 136 M3 batch pan

Strike pans in Australian raw sugar mills are agitated predominantly by the convection created from steam heated calandrias. Mechanical stirrers are used in some applications but are of high capital cost and subject to uncontrolled air leakage around glands. An improvement to boiling in a batch strike pan at Tully Mill was considered essential to achieve forecast crushing rates, and changes to the process were necessary. A controlled quantity of air was fired into the pan to promote massecuite circulation in the A massecuites using an installation manufactured by airGUT (pronounced "airgoot") in Spain. Pan boiling times were reduced by approximately 11 % when boiling average A massecuite of 87.2 true purity to produce an A molasses true purity of 71.8. The effective pan boiling rate was increased from 80 tlh to 89 tlh of massecuite.