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Carbonation of quicklimes degrades their quality and can occur when process temperatures become sufficiently low. This risk can be heightened in process atmospheres containing high CO2 and steam. To assess this, carbonation experiments involving atmospheres with different CO2 concentrations and steam were performed at 700 °C on 2.5–5 mm quicklime granules derived from sedimentary and metamorphic limestones. The carbonation extents of the quicklimes derived from metamorphic limestones during the fast stage were higher, corresponding with their larger specific surface areas. However, SEM analysis revealed that these quicklimes had fine structures with relatively small pores that likely became blocked during carbonation, causing plateauing of carbonation that appeared to be mainly limited to particle surfaces. The presence of steam caused only mild enhancements in carbonation of these quicklimes. Contrastingly, the quicklimes derived from sedimentary limestones had lower specific surface areas that concurred with their thicker structures and larger pores. The carbonation extent during the initial fast stage was correspondingly lower, but carbonation progressed at a sustained rate thereafter. The resulting high carbonation extents appeared to be facilitated by the larger pore volumes available for carbonate growth, including locations inside particles. The presence of steam greatly enhanced the carbonation of these quicklimes. Overall, every quicklime exhibited high carbonation extents despite being granular-sized. Moreover, their distinctive carbonation behaviors and microstructures could be delineated by their parent limestone type. These findings should be considered when carbonation in high CO2 atmospheres may occur, e.g., during cooling in electrical lime kilns.

The quality of limestone is crucial for limestone suppliers, as is that of quicklime to its producers and their customers. Quality requirements vary depending on the industrial application, and understanding the factors affecting quality is of great importance in industry. Quicklime is produced via the calcination of limestone in high-temperature kilns—a process that emits large quantities of carbon dioxide (CO2). Increased knowledge of the factors influencing quicklime quality would help reduce the associated CO2 emissions, increase material efficiency, and reduce energy consumption, while increased knowledge of the chemical composition of the raw materials would make the mining process more efficient.

A thermal decrepitation study was performed on 80 limestone samples. This involved analyzing the chemical composition, thermal decrepitation, and crack formation. The results of this study showed that thermal decrepitation does not correlate with the chemical composition of limestone. Instead, it was suggested that that thermal decrepitation can be explained by the thermally induced formation of cracks.

Slaking reactivity experiments were performed on quicklimes produced in a CO2 atmosphere at various calcination times and temperatures. The specific surface areas of the quicklime samples were measured and correlated with the calcination times and temperatures. Based on statistical analysis of the experimental data, the highest-reactivity quicklime was obtained at a low calcination temperature and medium-to-long calcination time, while the quicklimes with the highest specific surface areas were obtained at low calcination temperatures and low calcination times.

A carbonation study was carried out to investigate the effect of different atmospheres on the carbonation of quicklimes derived from two types of limestones: sedimentary and metamorphic. Three different carbonation atmospheres were investigated, one represented the flue gas in a conventional fuel-fired kiln and the other two an electrically heated kiln with dry and wet limestone feeds, respectively. It was found that the carbonation of quicklime varies, depending on the gas composition and limestone type.

Trace element analysis was performed on stromatoporoid limestone, crinoid limestone, reef limestone, fragmentary limestone, marl consolidated, marl soft, and clay layer. Zinc (Zn) and lead (Pb) concentrations were determined by means of two different spectroscopy methods, one of which was performed on bulk samples, while the other was performed on phases within the samples. The results showed that the highest Zn and Pb concentrations were found in the silicon (Si)-rich phases of the marl soft and clay layer.

To produce quicklime, high calcium carbonate rocks, including limestone, are burned in industrial kilns at 1100–1450 °C. As a consequence of the high temperatures, the carbonate rock can break and decrepitate into fine material, causing operational problems and material losses. In the present paper, an industrial case study on thermal decrepitation was performed on Boda Limestone from the Jutjärn quarry in Dalarna, Sweden. We analyzed 80 limestone samples for thermal decrepitation; furthermore, the correlation with chemical composition was statistically analyzed. The experiments were complemented by a detailed analysis of thermally-induced cracking at a range of temperatures (ambient, 500 °C, 800 °C, and 1150 °C) for two limestone samples with similar chemical compositions but with very different decrepitation behaviors. Decrepitation was analyzed by an in-house method, the chemical composition by XRF, and the thermally-induced cracking was investigated by SEM and image analysis. No strong correlation was found between thermal decrepitation and the chemical composition of the limestone. For the sample with low thermal decrepitation, a dense narrow network of fractures was found after full calcination; however, this network was not observed in the sample with high thermal decrepitation. A plausible explanation for the different decrepitation behaviors is that this fracture network releases internal stress and stabilizes the calcined rock. The obtained results can help in predicting limestone thermal decrepitation, enabling increased resource efficiency in quicklime production.