Intermediate-temperature and hot lime clarification processes for sugar processing

This technology consists of two improved processes for clarifying sugar cane juice during the produc-tion of raw sugar—an intermediate-temperature lime clarification process and a hot lime clarifica-tion process. Introduced into sugar factories in Louisiana, Texas and Florida, the technology replaces the traditional and inefficient cold lime clarification process cur-rently used to process sugar. In intermediate-temperature lime clarification, mixed juice from sugar cane is heated to an “inter-mediate” temperature of 150°F, then incubated and limed for 12 to 15 minutes. With hot lime clarification, the juice is heated first to 150°F and incubated, and then limed at 215°F for only 30 seconds. Both the intermediate-temperature and hot lime clarification processes perform much bet-ter than cold-temperature lime clarification, re-moving impurities from the juice more effectively, requiring less lime, and making it easier to heat when the water in the juice is later boiled away to make raw sugar. The processes also save money by reducing expensive losses of sucrose, and reducing the amount of bacteria that sometimes grow in the juice and destroy the sugar. The technology, which has been adopted by 100% of the sugar factories in Louisiana and Texas, was transferred by working closely with three sugar fac-tories and demonstrating all the steps in the process and the monetary benefits of shifting to one of the new processes. After these three factories converted and numerous other technology transfer efforts were made, such as presentations at sugar technologists’ meetings and at individual factories, the other factories recognized the benefits and also adopted the new processes. All but two Florida sugar factories have converted to one of the new processes, and international compa-nies are showing interest. It has been conservatively stimated that the new processing methods are sav-ing the U.S. sugar industry in Louisiana, Texas, and Florida over $3,103,000 per year.
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