Patent ID: 7387769

Claim:
A method for precipitating calcium carbonate from a liquid containing calcium hydroxide and water comprising the steps of: providing a continuous flow of the liquid along a serpentine path sequentially through a plurality of chambers in a vessel having an inlet and an outlet, each of the plurality of chambers having a point of entry and a point of exit positioned diagonally opposing one another defining the serpentine path, and the plurality of chambers being arranged to permit the liquid to flow sequentially from the first of the chambers to the last of the chambers, said arrangement being defined by the point of exit of one chamber being connected to the point of entry of the subsequent chamber, wherein the point of entry of the first chamber is the inlet of the vessel and the point of exit of the last chamber is the outlet of the vessel; and introducing a reactant gas into the liquid in the plurality of chambers, the reactant gas being introduced via a single supply pipe which is manifolded to individual supply pipes that extend into respective ones of the plurality of chambers, the reactant gas being introduced into the liquid in the plurality of chambers via the individual supply pipes extending below the level of the liquid, wherein the liquid and the reactant gas react to form precipitated calcium carbonate without any mechanical agitation.