PROBLEM TO BE SOLVED: To provide a method for freeze-concentrating a solution that can shorten the operating time of a freeze-concentrator and largely improve efficiency in production, economy, and the like, and is also excellent in environmental protection when the concentrated solution that is a solution is concentrated by freeze-concentration.SOLUTION: When the concentrated solution 3 is converted into a solid-liquid mixture by producing an ice crystal in it by cooling, the concentrated solution is heated by a heating means in accordance with a timing when the ice crystal is produced in the concentrated solution 3, and after the ice crystal of relatively small particle sizes (ice crystal (small) 8a) produced in the concentrated solution 3 is melted by the heating, the ice crystal (ice crystal (large) 8) that remains in the concentrated solution 3 is allowed to grow, thereby converting the concentrated solution 3 into the solid-liquid mixture.COPYRIGHT: (C)2010,JPO&INPIT【目的】凍結濃縮により溶液たる被濃縮溶液を濃縮する際に、凍結濃縮装置の運転時間を短縮できて、生産面や経済面等の効率を大に向上でき、しかも環境保護にも優れる溶液の凍結濃縮方法を提供できるようにした。【解決手段】冷却により、被濃縮溶液3中に氷結晶を生成させて同溶液を固液混合物化する際に、被濃縮溶液3中に氷結晶が発生するタイミングに合わせて同被濃縮溶液を加熱手段によって加熱し、同加熱により、被濃縮溶液3中に生じた比較的小なる粒径の氷結晶(氷結晶(小)8a)を融解させてから同被濃縮溶液3中に残留する氷結晶(氷結晶(大)8)を成長させて被濃縮溶3液を固液混合物化する。【選択図】 図1
