Novel Ice Maker

Ice makers are ubiquitous in hotels, commercial kitchens and anywhere else that beverages are served. They are also high users of energy and water. Energy is consumed in the freezing process and in the harvest process. Typically, ice is formed on a refrigeration evaporator within the machine. Water flows over the evaporator and drips into a tray beneath the evaporator where it is pumped back to the top and recirculated over the evaporator surface. Eventually, ice builds up to a satisfactory thickness and it is released or harvested from the evaporator.

Harvesting is initiated in all ice makers by reversing the refrigeration system flow and applying heat to the evaporator much like a heat pump works. The evaporator metal must be warmed from well below freezing to a point where a layer of water forms between the evaporator and the ice, so it slips off. Typically about 30% of the energy in an ice maker is used for harvest.

After harvest, the evaporator is cooled to ice-making temperature and the cycle begins again. Ice-making time is lost during the harvest and subsequent cool-down period and this limits ice maker capacity.

Our client had a better idea for releasing the ice from the evaporator where the heating process and subsequent harvest occurred much more rapidly and with far less energy. We were asked to construct a working model of the concept for use in discussions with funding groups.

The prototype was constructed using the theoretical operating principle for the concept, and was capable of producing ice at a scaled rate that demonstrated full-scale capability. Control for the machine was with a LabView interface. The prototype was completed, fine tuned and demonstrated to the client, then delivered to their facility for subsequent review with funding groups.