Abstract: By supplying a refrigerant utilized for cooling brine at a brine chiller unit (4) to a cooler (21) of a blast chiller (2), the internal space at the blast chiller (2) is cooled. In addition, the brine cooled at the brine chiller unit (4) is supplied to an ice heat storage tank (23) during the night and is supplied to a cold trap (7) during the daytime by switching a three way reversing valve (17). Thus, ice-making and chilled water storage are achieved at the ice heat storage tank (23) during the nighttime so that a tumble chiller (3) performs cooling during the daytime by using the chilled water that has been stored at the ice heat storage tank (23). Consequently, during the daytime, three coolers, i.e., the vacuum cooler (1), the blast chiller (2) and the tumble chiller (3), can be operated with a single brine chiller unit (4).

Abstract: A multiplicity of water passage pipes (4) are received in a horizontal, cylindrical-shaped drum (3), which is provided at an upper portion thereof with a discharge port (3a) and an inflow port (3b) for a refrigerant. Fixed to both ends of the drum (3) are a water introduction cylinder (6) and a discharge cylinder (7), which is bent downward to be substantially L-shaped. A heat exchanger (1) is secured such that en end thereof on a side of the discharge cylinder (7) is disposed above a cold water tank (2). An interior of the cold water tank (2) is divided into a first tank (2a) and a second tank (2b) by a partition (8), over which water can flow. A piping for supplying a cold water to a facility for utilization of the cold water is connected to a bottom or a lower portion of the first tank (2a), on which the cold water from the heat exchanger (1) falls. A path for water recovery from the facility for utilization of the cold water is connected to the second tank (2b) through a return piping (11).