Techniques for growing crystalline calcium carbonate solids such that the crystalline calcium carbonate solids include a volume of 0.0005 mm.sup.3 to 5 mm.sup.3, include a slaker to react quicklime (CaO) and a low carbonate content fluid to yield a slurry of primarily slaked lime (Ca(OH).sub.2); a fluidized-bed reactive crystallizer that encloses a solid bed mass and includes an input for a slurry of primarily slaked lime, an input for an alkaline solution and carbonate, and an output for crystalline calcium carbonate solids that include particles and an alkaline carbonate solution; a dewatering apparatus that includes an input coupled to the crystallizer and an output to discharge a plurality of separate streams that each include a portion of the crystalline calcium carbonate solids and alkaline carbonate solution; and a seed transfer apparatus to deliver seed material into the crystallizer to maintain a consistent mass of seed material.

The present invention relates to a system and a method for cleaning and recycling chlorine bypass dust, and to a system and a method for cleaning and recycling chlorine bypass dust in which the chlorine concentration of calcium carbonate is reduced by adding a post-treatment process, in addition to obtaining potassium chloride (KCl) as a raw material of chemical reagents such as pharmaceuticals from chlorine bypass dust and obtaining calcium carbonate as a raw material for building materials such as fillers, scouring agents, adhesives, and cements, by proposing the system for cleaning and recycling chlorine bypass dust.

Methods of making settable compositions that include uncured carbonate aggregates are provided. Aspects of the methods include: preparing a carbonate slurry, subjecting the carbonate slurry to rotational action (optionally with an aggregate substrate), to produce an uncured carbonate aggregate, and then combining the uncured carbonate aggregate with a cement component and a liquid to produce the settable composition. Also provided are settable compositions produced by the methods and uses thereof.