Abstract
It is well known that the temperature of slurry ice manufactured with the concentration of salt water in the range of 1.0∼2.0wt% can be accurately maintained in the range from -0.5 to -1.5°C. Now, pioneering work on a slurry ice manufacturing apparatus has already been made practicable by researchers in Canada and Germany. In their approach, ice particles made with the concentration of salt in sea water are blended with a solution consisting of a mixture of sea water and fresh water. However, the apparatus is very large. The authors therefore intend to develop a slurry ice manufacturing apparatus that uses only one unit to produce slurry ice from the solution of salt with a concentration below 1.0wt%. As a result, the authors successfully developed the generator in the apparatus on the basis of the method in which the ice layer produced on the heat transfer surface is swept out using scrapers. In addition, in order to establish the design engineering of this generator, experiment has been carried out to study the amount of ice produced from 1.0∼4.0wt% NaCl solution and measure the concentration of salt. The results indicate the following: (i) The speed at which ice is produced is determined by the initial concentration of the salt solution and remains constant when IPF≤20 IPF : ice packing factor). (ii) The speed of ice production can also be controlled by adjusting the temperature of the refrigerant. (iii) The thermal conductance of the ice layer tends to change with the salt concentration of the solution.
