A Programmed Indirect Freezing Process with in-situ Washing and in-situ Melting Operations.

摘要

A programmed indirect freezing process with the following features was studied: It is a cyclic process to be conducted in a unified freezer-melter and each cycle consists of a feeding step, a freezing step,an in-situ washing step and an in-situ melting step. By an appropriate coordination of the design of a unified freezer-melter and the control of the freezing step, a consolidated ice bed of a structure similar to that of a hydraulic ice washing column used in a direct contact freezing process is obtained at the end of each freezing step. Therefore,an efficient washing of ice bed can be accomplished with a small loss of wash water. New ways of accomplishing heat reuse,such as the use of a working medium which undergoes solid to liquid transformations and the method based on low pressure freezing and high pressure melting operations,have been incorporated in the process to significantly reduce the energy requirement. (Author)