Light-burned dolomite

Light-burned dolomite (or dolime) is produced in either rotary or shaft kilns. The principles are similar to those of making high calcium quicklime. Heat usages are presumably somewhat lower, owing to the lower heat of calcination of dolomite and its lower dissociation temperature. 

Some very light-burned dolomitic limes are hydrated at atmospheric pressure in a similar way to high-calcium limes. They use maturing bunkers to provide 12 to 24 hours of residence at 80 to 90 °C in the presence of excess water. 

The overall reduction of light burned dolomite and ferrosilicon is given by " ... 

Porosity. Part of the porosity of particles of commercial quicklime arises from the porosity of the limestone, and part from the decomposition process. The porosity of conunercially produced quicklime can be as high as 55% (by volume), when a porous limestone is lightly burned. Exposure to elevated temperatures results in sintering (see sections 15.4 and 15.5), which can reduce the porosity to below 25 %. Dead-burned dolomite has a porosity of about 10 %. 

The lime should be light-burned, particularly in the case of dolomitic lime. It should have a particularly low residual CO2 content, of less than 0.2%, to minimise contamination of the magnesium hydroxide. 

Four qualities of calcined dolomite are produced — half-, light-, hard-, and dead-burned. 

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