PROBLEM TO BE SOLVED: To secure a cooling part and freezing part of high performance to lower initial cost and running cost in a freeze concentrator or ice maker by positively utilizing cold fresh air that is natural energy to perform cooling and freezing of water to be concentrated or to be made ice. SOLUTION: A cold energy absorbing and accumulating heat exchanger 3 for absorbing and accumulating cold energy of fresh air 1 in a liquid refrigerant and a ice layer forming machine 2 for forming an ice layer or ice from water to be concentrated or water to be make ice are connected by a circulating circuit 4 for the cold energy absorbing and accumulating liquid refrigerant, and in mid-way of it, a pump 5 is arranged. And since the refrigerant is liquid, concerning absorbing accumulation of cold energy to the liquid refrigerant, making the cold energy have high density and a decrease in heat transfer resistance are attained to allow the formed quantity of the ice layer to be increased. And in the heat exchanger 3, the cold fresh air 1 may be either forced air by a fan 6 or the like or natural air. Furthermore, as the ice layer forming machine 2, the falling or drum type one or the like can be used.
展开▼
