Lime systems in sugar mills - opportunities for improvement

A survey of Queensland sugar mills was undertaken in 1997 to determine which issues, with regard to lime usage, needed addressing. The main conclusion was that most Queensland sugar mills have very low levels of control of the slaking and subsequent addition of lime to juice clarification circuits. The properties of quicklime used need to be taken into account to allow the correct product to be specified. These properties are also important in establishing necessary controls to provide slurry with the best properties for the sugar process. The lack of these controls, combined with the properties of quicklime, creates potential problems and opportunities for most mills. This paper presents initial findings of the survey, considers several areas of lime use, and points out some major issues and possible improvements.