CRYSTALLIZATION REACTION APPARATUS PROVIDED WITH MEANS FOR MEASURING TURBIDITY AND CRYSTALLIZATION METHOD TO USE THE SAME

PROBLEM TO BE SOLVED: To provide a crystallization reaction apparatus provided with a turbidity measuring means for lessening the white turbidity of the treated water rapidly and a crystallization method to use the crystallization reaction apparatus. SOLUTION: This crystallization reaction apparatus is provided with a crystallization reaction tank 1 in which a seed crystal 2 is packed so that the crystallization reaction is promoted for removing the component to be crystallized from raw water, a raw water supplying means for supplying the raw water to the tank 1, a crystallizing liquid chemical supplying means for supplying a crystallizing liquid chemical to the tank 1 and a treated water circulating means for returning at least a part of the treated water discharged from the tank 1 to the tank 1, a turbidity measuring means 15 for measuring the turbidity of the treated water discharged from the tank 1 and a raw water supply controlling means 12 for controlling the amount of the raw water to be supplied to the tank 1 from the raw water supplying means and/or a crystallizing liquid chemical supply controlling means 14 for controlling the amount of the crystallizing liquid chemical to be supplied to the tank 1 from the crystallizing liquid chemical supplying means according to the turbidity measured by the means 15.