Light-burned quicklime

Thus the properties of quicklime from a given kiln reflect the average properties of individual lumps, each of which has experienced a particular time-temperature history. Fig. 15.8 compares the distribution of particle densities for a light-burned quicklime from an annular shaft kiln, with a mean apparent density of 1.66 g/cm with that of a solid-burned quicklime from a coal-fired traditional shaft kiln with a mean apparent density of 2.15 g/cm. Table 15.4 presents some typical... 

Another aspect of reactivity and mean apparent density is that, as reported in [27.17], at the final temperature in the BOF of 1,600 °C, lightly burned quicklime sinters to medium burned within 5 min. and to hard burned within 10 min. (Table 27.5). 

Light-burned quicklime is quicklime that is lightly sintered and has a high reactivity to water. 

Soft-burned quicklime see light-burned quicklime. 

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 %. 

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. 

---