Performance Criteria for Hydrated Limes

The finished product has a specific surface area of 35 to 43 m /g. It is reported to have good handling properties, to disperse well, and to be significantly more effective at removing acid gases than normal hydrated limes [20.12]. 

Details of this process are still largely confidential. An early patent [20.14] described the hydration of reactive, fine lime (e.g., less than 6 mm) with water in the presence of an amine/glycol additive. Specified compounds were mono-, di- and tri-ethyleneglycols and mono-, di- and tri-ethanolamines, and mixtures thereof. Hydrates with surface areas of 46m /g were cited. 

It is understood that the process has since been developed and that further patents are pending [20.17]. 

A variety of test methods are available to characterise hydrated lime. As they all measure different parameters, the choice of the most appropriate method(s) depends on the application. 

The chemical activity of hydrated lime can be measured in at least three ways, namely by  

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