Dryer for drying precipitated calcium carbonate

Abstract

A dryer (1) for drying precipitated calcium carbonate (PCC) includes a drying chamber (2) that delimitates inside a drying space (3) to host the PCC, heating means (4,8) to heat the drying chamber (2), moving means (9,10) to move the drying chamber (2), in order to cause a movement of the PCC in relation with the drying chamber (2) and one or more items (11) that increase the thermal exchange surface with the PCC, where the items (11) are located in the drying space (3) and can move compared to the drying chamber (2), in order to move in relation to the drying chamber (2) during its movement.

Description

technical field [0001] The present invention relates to a dryer for drying precipitated calcium carbonate (PCC). Background technique [0002] The demand for fine powder and ultrafine powder of highly pure calcium carbonate, especially from the chemical, metallurgical, food, and paper industries, is increasing. [0003] The production of bulk calcium carbonate powder is usually achieved through a process with the following three main stages: [0004] - Burning (calcination) of natural limestone CaCO 3 , to utilize CaCO through the calciner 3 + heat -> CaO + CO 2 The reaction to obtain lime CaO; [0005] - lime CaO and carbon dioxide CO in aqueous solution (milk of lime) 2 between carbonation to utilize Ca(OH) through the recombination reactor 2 +CO 2 ->CaCO 3 +H 2 O+ heat reaction to obtain pure precipitated calcium carbonate (PCC); [0006] - Thickening and drying the precipitated calcium carbonate (PCC) until it is suspended in water (PCC slurry) to obtain ...

AI Technical Summary

Problems solved by technology

[0009] Known methods of drying PCC pulp have the disadvantage that the heat exchange between the combustion reaction and the PCC pulp is not efficient enough to provide a large amount of powder in a given time precipitated calcium carbonate, power consumption issues, and the issue of reducing the overall size of the dryer

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